P. Hiscott, RM Maggie et al (Dept. of Ophthal, Univ. of Liverpool, UK)
Clinicopathological correlation of epiretinal membranes and posterior lens opacification following perfluorohexyloctane tamponade.
Br.Jr of Opthal, February 2001: 85; 179-183.
This study was undertaken to find histological evidence that perfluorohexyloctane (F6H8) has a role in the formation of epiretinal and retrolental membranes following tamponade retinal procedures for retinal detachment.
Eight epiretinal membranes and 3 opaque posterior lens capsule were excised from patients in whom F6H8 was used. These membranes and capsules were examined using light microscopic methods, including immuno-histochemistry.
The membranes exhibited a dense macrophagic infiltration, some of them contained multinucleated cells. Macrophages containing large intracytoplasmic vacuoles represented upto 30% of the cells. This macrophagic infiltration may be a histological reaction to F6H8.
Further investigations concerning the cellular response to the tamponade agent are warranted.
T.A. Citulla, M H Criswell et al (Dept. of Ophthal. Indiana Univ. School of Medicine, Indianapolis)
Intravitreal Triamcinolone Acetonide Inhibits Choroidal Neovascularization in a Laser-treated Rat model.
Arch.Ophthl, vol.119, March 2001, p.399-404.
Nineteen anaesthesized male rats received a series of 8 krypton red laser lesions per eye, for different durations and different intensities.
One eye received intravitreal triamcinolone acetonide (TAAC) while the other eye received an injection of isotonic sodium chloride solution.
It was found that intravitreal TAAC is a potent inhibitor of fibrovascular proliferation in a rat model of choroidal neovascular membranes induced by laser trauma.
C Haritoglou, O Ehrst, et al (Dept. of Ophth.Ludwig-Maximilians – Univ. Munich, Germany)
Paracentral scotomata: a new finding after vitrectomy for idiopathic macular hole
Br.J Ophthal. Feb.2001, vol.85(2): 231-233
In this study of 15 patients, static microperimetry was performed preoperatively and 6 or 12 weeks postoperatively (after vitrectomy).
Surgery consisted of standard 3 port vitrectomy including removal of epiretinal membranes and the inner limiting membrane.
Postoperative paracentral scotomata were detected in areas, which tested as normal prior to surgery. They were located temporally and/or inferiorly.
The authors claim this study to be the first series of patients in whom small, asymptomatic paracetnral scotomata were detected as a complication following vitrectomy for idiopathic macular hole.
MW Johnson, MR VanNewkirk,KA Meyer (Univ. of Michigan, School of MedicineAnn Arbor and Univ of Melbourne, Australia)
PerifovealVitreous Detachment Is the Primary Pathogenic Event in Idiopathic Macular Hole Formation.
Archives of Ophthalmol. Vol.119, Feb.2001, pp.215-222
The authors studied twenty-six eyes with stage 1 or stage 2 idiopathic macular hole.
Complete examination included contact lens biomicroscopy, b-scan ultrasonography and in some cases vitreo-retinal surgery where the posterior cortical vitreous layer was examined with a silicone tipped cannula.
The authors conclude that localised perifoveal vitreous detachment (an early stage of age-related posterior vitreous detachment) is the primary pathogenic event in idiopathic macular hole formation. Detachment of the posterior hyaloid from the pericentral retina leads to foveal dehiscence by exerting anterior traction on the foveola followed by localizing into the foveola, the dynamic vitreous traction associated with these rotations.
K J Cruickshanks, R Klein, et al (Univ of Wisconsin, Madison)
Sunlight and the 5-Year Incidence of Early Age-Related Maculopathy
Archives of Ophthal, vol.119, Feb.2001, pg.246-250.
This longitudinal, population based study was carried out on participants (aged 43-86 yrs), who were re-examined between 1993 and 1995, five years after base line investigation.
Leisure time spent outdoors while persons were teenagers (13-19 yrs) and in their thirties (30-39 yrs) was significantly associated with the risk of early ARM.
The use of hats and sunglasses had a slight, but insignificant protective effect. People with red or blonde hair were slightly more likely to develop early ARM than people with darker hair.
The authors conclude that exposure to sunlight may be associated with development of early ARM.
R J Casson, F K Fleming et al (Aylesbury, England)
Bilateral Ocular Ischemic Syndrome Secondary to Giant Cell Arteritis.
Archives of Ophthalmol, vol.119, feb.2001, p.306
This is a case report of an 83 yr old woman with bilateral loss of vision, following several weeks of weight loss, headache, scalp tenderness and jaw claudication.
On examination there was no light perception in either eye, both corneae were edematous, and there was marked hypotony.
The clinical findings suggested bilateral ocular ischemic syndrome secondary to giant cell arteritis. Temporal artery biopsy confirmed the diagnosis.
The patient was treated with 200mg of i.v. hydrocortisone phosphate followed by oral prednisolone 80mg/day. Though the corneae cleared and intraocular pressure returned to normal, visual acuity did not recover due to bilateral optic atrophy.
The authors comment that ocular ischaemic syndrome is caused by global vascular insufficiency. There is corneal oedema, anterior uveitis and hypotony. The posterior segment changes include optic disc edema, retinal haemorrhage and cotton wool spots.
Treatment of giant cell arteritis with systemic steroids may improve the perfusion of the anterior segment reducing the chance of developing rubeosis or phthisis.
RSB Newsom, J C McAlister, et al (King’s College Hospital, Denmark Hill, London, UK)
Transpupillary thermotherapy (TTT) for the treatment of choroidal neovascularisation.
Br.J. Ophthalmol, 2001; 85: 173-178
Transpupillary thermotherapy (TTT) is delivered by a diode laser. Its effectiveness for the treatment of classic and occult choroidal neovascularisation (CNV) was tried in 44 eyes of 42 patients with CNV secondary to age related macular degeneration (ARMD).
The authors found that TTT was able to close choroidal neovascularisation, while maintaining visual function. Further trials of TTT are needed to compare this intervention with other treatment modalities.
B A Handwerger, A W Urban, et al (Univ.Ave, Suite, Madison Wis)
Retinopathy as the Initial Presentation of Human Immunodeficiency Virus 2 Infection.
Archives Ophthalmol, Vol.118, Dec. 2000, pg.1695-96.
This is a case report of a 42 yr. African man who had immigrated 8 years earlier to USA and in whom a retinal abnormality was found on routine examination. He had no visual complaints.
Fundus examination showed several cotton wool spots and intraretinal haemorrhage at the posterior pole of the right eye.
Left eye showed a small cotton wool spot at the posterior pole and a blot haemorrhage in the temporal periphery.
A diagnosis of HIV-2 infection was made based on positive specific HIV-2 enzyme immuno assay and Western blot analysis results.
The authors comment that patients with HIV-2 infection appear to have less infectious retinopathy than patients with HIV-1 infection.
Moreover, patients with HIV-2 infection had no evidence of cytomegalovirus retinitis or varicella zoster infection.
In this small study, the predominant ocular feature was non-infectious retinopathy seen in 5 (14%) of 37 patients.
There is evidence that HIV-2 infection may decrease the risk of subsequent HIV-1 infection.
A S Unsold, JF Rizzo, S Lessell (Harward Medical School and the Mass. Eye and Ear Infirmary)
Optic Neuropathy after Burns.
Arch.Ophthalmology, Vol.118, Dec.2000, pg.1696-1698.
The authors examined 2 new cases of post-burn optic neuropathy and identified 10 additional cases in medical literature.
Loss of vision was severe and bilateral, with disc oedema present in most cases. Retinal haemorrhages and oedema were observed in some cases. There was a capacity for spontaneous recovery.
Patients with cutaneous scalds and thermal burns may develop bilateral optic neuropathy. The pathogenesis of this visual loss has yet to be established. Various hypothesis, include demyelination caused by a toxin released from burned skin, hypotension leading to ischaemic neuropathy or a combination of aetiological factors in patients having respiratory infections and metabolic complications and receiving multiple medications.
C.L. Shields, MCM Santos, et al [ Thomas Jefferson Univ, Philadelphia]
Thermotherapy for Retinoblastoma
Arch Ophthalmol 117: 885-893, 1999
Options for treating retinoblastoma are enucleation, external beam radiotherapy, plaque radiotherapy, laser photocoagulation, cryotherapy, chemoreduction and thermotherapy. Conservative focal treatments are preferred so that enucleation or external beam radiotherapy can be avoided.
188 retinoblastomas in 80 eyes [ from 58 patients] were studied in this prospective non-randomized trial.
It was found that thermotherapy provided satisfactory control for selected retinoblastoma. Tumors 3 mm in diameter greater at the time of thermotherapy require more intense treatment than smaller tumors and are at a greater risk for ocular complications. In this series of carefully selected cases, complete tumor control was achieved in 86% of cases.
W M Tang, TM Topping, (Dept. of Ophthal.- Boston Univ.- MA)
Vitreous Surgery for Central Retinal Artery Occlusion
Arch.Ophthalmol, vol.118, Nov.2000; p.1586-1587
This is a case report of a 68-yr old diabetic male who developed central retinal artery occlusion (CRAO) in his left eye.
Thirty hours after conventional treatment, there was no visual improvement. The patient agreed to the option of vitrectomy with vessel cannulation and thrombus disruption.
After vitrectomy a microvitreoretinal blade was used to penetrate the arterial wall at the central bifurcation of the retinal artery.
A 50-gauge flexible stylet (made of nickel titanium) was extended from a 19 gauge support shaft and used to cannulate the CRA through the arteriotomy site.
Vision gradually improved and finally the corrected visual acuity was 20/25 four months after CRAO.
Ohji M, Nao-I N, Saito Y, et al (Osaka Univ, Japan; Miyazaki Med College, Japan)
Prevention of Visual Field Defect After Macular Hole Surgery by Passing Air Used for Fluid-Air Exchange Through Water.
Am J Ophthalmol, 127: 62-66, 1999
This study compared preoperative and postoperative visual fields in 39 patients who had macular hole surgery using the standard vitrectomy procedure, with another group of 33 patients who had macular hole surgery with humidified air.
It was found that in the standard vitrectomy group, 23% of patients had peripheral visual field defects. No patients had a visual field defect in the group that received humidified air.
This implies that use of room-air may cause desiccation of the retina during fluid-air exchange. Therefore, humidification of air before use in fluid-air exchange during vitrectomy is strongly recommended in order to prevent field defects.
JA Khawly, RJ Lambert, GJ Jaffe (Duke Univ, Durham, NC; Alcon Labs, Ft Worth, Tex)
Intraocular Lens Changes after Short and Long term Exposure to Intraocular Silicone Oil: An In Vivo Study.
Ophthalmology 105: 1227-1233, 1998.
The effects of short-term exposure to silicone oil on polymethylmethacrylate (PMMA), silicone, and soft acrylic intraocular lenses (IOLs) were studied (in rabbits).
It is extremely difficult, if not impossible to remove the remaining silicone oil from the posterior surface of a silicone IOL – both after short term and long term exposure.
This oil can interfere with the surgeons’ view of the retina and can also reduce the patient’s visual acuity. By contrast, removing oil from the posterior surface of an acrylic IOL is easy. Hence, a soft acrylic or PMMA IOL should be used instead of a silicone IOL, for patients who may need vitreoretinal procedures with silicone oil tamponade.
RE Warwar, JD Bullock, D Ballal (Wright State Univ, Dayton, Ohio)
Cystoid Macular Edema and Anterior Uveitis Associated with Latanoprost Use: Experience and Incidence in a Retrospective Review of 94 patients.
Ophthalmology 105: 263-268, 1998.
Latanoprost, a prostaglandin analogue, is the first of a new class of drugs developed to reduce intraocular pressure.
Out of 94 patients and a total of 163 eyes reviewed anterior uveitis developed in 6.4% of the patients and in 4.9% of all eyes during latanoprost treatment. CME occurred in 2.1% of patients and in 1.2% of all eyes.
Clinicians need to be aware of these possible complications when using latanoprost.
T.Abe, S Hayasaka, Y Nagaki, et al (Toyama Med and Pharmaceutical Univ, Japan)
Pseudophakic Cystoid Macular Edema Treated With High-Dose Intravenous Methylprednisolone.
J Cataract Refract Surg. 25: 1286-1288, 1999
High-dose I.V. methylprednisolone was found to be effective in treating pseudophakic cystoid macular oedema (CME) in a study of 4 patients. Visual acuity improved in 3 of the 4 eyes.
Each of the 4 patients had a ruptured posterior capsule for which anterior vitrectomy was done. The latter may also have played a role in improving visual acuity.
Grover S, Fishman GA,Anderson RJ, et al (Univ of Illinois, Chicago; Univ of Sao Paulo, Brazil; Jules Stein Eye Inst, Los Angeles; et al)
Visual Acuity Impairment in Patients with Retinitis Pigmentosa at Age 45 Years or Older.
Ophthalmology 106: 1780-1785, 1999
This is a study of 999 patients with various genetic subtypes of retinitis pigmentosa (RP) and Usher syndrome (RP with congenital hearing loss) from four US eye centres.
It was found that few patients (not more than 0.5%) with RP or Usher’s syndrome lose all vision in both eyes. One fourth of patients, have visual acuity of 20/200 or worse in both eyes, most have acuity of 20/40 or better in at least one eye.
M Paques, JN Vallee, et al (Dept. of Ophthalmology, Neuroradiology and Anesthesiology, Hopital Lariboisiere, Universite, Paris).
Superselective ophthalmic artery fibrinolytic therapy for the treatment of central retinal vein occlusion.
Br J Ophthalmol 2000; 84:1387-1391
Twenty-six patients were reviewed in a retrospective university based single centre study. Among these 26 patients, there were nine cases of combined artery and vein occlusion, three cases of combined cilioretinal artery and central retinal vein occlusion (CRVO) and 14 cases of classic CRVO. The therapeutic procedure comprised the infusion of urokinase through a micro-catheter into the ostium of the ophthalmic artery, via a femoral artery approach.
Six eyes showed significant improvement in visual accuity immediately after the fibrinolysis procedure. Among them, four had an initial fundoscopic appearance suggestive of combined occlusion of the central retinal artery (CRAO) and vein. Visual benefit was maintained in the long term for these patients.
This treatment did not prevent the occurrence of ischaemia in the failure cases.
The efficacy of the procedure needs to be further evaluated in a controlled study. During catheterization procedure, none of the patients developed neurological symptoms, and no extraocular side effects were noted after fibrinolysis.
Takanobu Tokuyama, Tomohiro Ikeda, et al (Hyogo College of Medicine, Hyogo, Japan)
Effects of haemodialysis on diabetic macular leakage.
Br.J Ophthal 2000; 84:1397-1400
The article describes a prospective study where fluorescein angiography was performed on 40 eyes of 22 non-insulin dependent diabetic patients with endstage renal disease just before and 4 weeks after the commencement of haemodialysis.
The results indicate that haemodialysis does not benefit macular leakage in diabetic patients receiving haemodialysis for endstage renal disease.
Wiedman M, Tabin GC (Harvard Med School, Boston; Univ of Vermont, Burlington)
High-Altitutde Retinopathy and Altitude Illness
Ophthalmology 106: 1924-1927, 1999
Altitude illness consists of acute mountain sickness, high altitude retinopathy (HAR), high altitude cerebral oedema (HACE) and high-altitude pulmonary edema.
The authors assessed 40 climbers in three Himalayan expeditions ascending to altitudes between 16000 and 29028 feet above sea level.
All participants had dilated fundus examination prior to during the climb and 2 days after reaching the highest altitude.
HAR developed in 19 of 21 climbers ascending to more than 25,000 ft. Fourteen of 19 climbers reaching 16,000 to 25,000 ft. had retinopathy. The authors developed a grading system for HAR based on the severity of retinopathy.
HAR was significantly associated with HACE.
Empirical treatment with oxygen, steroids, diuretics and immediate descent may be initiated to prevent HAR progression, or potentially fatal HACE.
Pearson PA, Piracha AR, Sen HA, et al (Univ of Kentucky, Lexington; Duke Univ, Durham, NC)
Atovaquone for the Treatment of Toxoplasma Retinochoroiditis in Immunocompetent Patients.
Ophthalmology 106: 148-153, 1999
The safety of atovaquone, was tested in a phase I trial for the treatment of toxoplasma retinitis in immunocompetent patients in an open-label, nonrandomized, prospective study.
Atovaquone (750mg 4times daily) was administered for 3 months to 17 patients, aged 18 to 75 yrs, with vision threatening ocular toxoplasmosis.
All patients improved within one to 3 weeks. The authors conclude that atovaquone is safe and effective for treatment of toxoplasma retinitis in immunocompetent patients.
Martin DF, Kuppermann BD, Wolitz RA, et al (Emory Univ, Atlant, Ga; Univ of California, Irvine; Kaiser Permanente, San Francisco; et al )
Oral Ganciclovir for Patients with Cytomegalovirus Retinitis Treated with a Ganciclovir Implant.
N Engl J Med 340: 1063-1070, 1999
The leading cause of visual loss in patients with AIDS, is cytomegalovirus (CMV) retinitis. Relapse after a brief control of retinitis (by administration of ganciclovir, cidofovir and foscarnet) occurs quickly.
Though a ganciclovir implant is more useful in controlling CMV retinitis, the risk of systemic manifestation remains.
Hence the authors carried out a study where patients were assigned randomly to one of 3 treatment groups:
(1) Ganciclovir implant and a placebo
(2) Ganciclovir implant and oral ganciclovir therapy
(3) Oral ganciclovir only.
The oral dose of ganciclovir was 4.5g/day. The incidence of Kaposi’s sarcoma was significantly reduced by the use of oral ganciclovir or intravenous ganciclovir as compared with placebo.
The results of the study indicate that the combined use of ganciclovir implant and oral ganciclovir at the higher 4.5gm daily dose delays the progress of existing retinitis and reduces the risk of additional CMV disease.
Husain D, Kramer M, Kenny AG, et al (Harvard Med School, Boston)
Effects of Photodynamic Therapy Using Verteporfin on Experimental Choroidal Neovascularization and Normal Retina and Choroid Upto 7 Weeks After Treatment.
Invest Ophthalmol Vis Sci 40: 2322-2331, 1999
Photodynamic therapy (PDT) is an emerging treatment method used for treatment of choroidal neovascularization (CNV); it is preferred to conventional laser photocoagulation where there is a significant risk of recurrence of CNV, as well as of sudden reduction of vision.
In PDT, a photosensitizing agent, verteporfin, is injected and accumulates in the neovascular and tumor tissue. The tissue, now photosynthesized is irradiated by light to the point of cytotoxicity. This method of treatment, allows selective closure of CNV while minimising damage to the overlying retina.
This study of PDT was carried out in monkey models. It was shown that PDT can demonstrate an absence of angiographic leakage for at least four weeks and recovery of the choriocapillaris and retinal pigment epithelium and preservation of the neurosensory retina at 7 weeks in the normal monkey eye models.
Smith W, Mitchell P, Webb K, et al (Australian Natl Univ, Canberra; Univ of Sydney, Australia)
Dietary Antioxidants and Age-Related Maculopathy: The Blue Mountains Eye Study.
Ophthalmology 106: 761-767, 1999
The Blue Mountain Eye Study assessed associations between the dietary intake of antioxidants and Age-related macular degeneration (AMD).
This study included a total population of 3654 patients, aged 49 yrs and older. The participants were assessed for the presence of AMD by masked grading of stereoscopic macular photographs.
This study found no statistically significant connection between the dietary intake of antioxidants – specifically carotene, zinc, vitamin C, retinol and AMD.
To date, no CONCLUSIVE evidence is available to support the benefit of supplements such as vitamins and antioxidants.
E Reichel, Berrocal AM, Ip M et al (Tufts Univ, Boston)
Transpupillary Thermotherapy of Occult Subfoveal Choroidal Neovascularization in Patients with Age-Related Macular Degeneration.
Ophthalmology 106: 1908-1914, 1999.
Transpupillary thermotherapy (TTT) involves heat delivery to the choroid and retinal pigment epithelium through the pupil with a modified diode laser. This article is a report of a pilot study in a small group of patients with AMD and occult subfoveal CNV. No side effects of TTT were found and the majority of patients had stabilizaiton or improvement of vision after TTT.
Holz FG, and the Radiation Therapy for Age-Related Macular Degeneration (RAD) Study Group (Univ of Heidelberg, Germany; et al)
A Prospective, Randomized, Double-Masked Trial on Radiation Therapy for Neovascular Age-Related Macular Degeneration (RAD Study)
Ophthalmology 106: 2239-2247, 1999.
The leading cause of legal blindness in Western countries, among persons over 50 years is age-related macular degeneration (AMD). Laser treatment is beneficial, but recurrence rate of AMD is about 50%. Laser photocoagulation is found to cause destruction of neurosensory retina, irreversibly.
Moreover, angiographic study cannot clearly distinguish neovascular membranes in most patients with AMD, and results of treatment of occult choroidal neovascularization (CNVs) are disappointing.
This article reports on the effectiveness of external beam radiation therapy for patients who have CNVs along with AMD.
The authors postulate that prospective, randomised trials are needed to achieve reliable results.
Klein R, for the Atherosclerosis Risk in Communities Study Investigators (Univ of Wisconsin, Madison; et al)
Prevalence of Age-Related Maculopathy in the Atherosclerosis Risk in Communities Study.
Arch Ophthalmol 117: 1203-1210, 1999.
Some evidence indicates that age-related macular degeneration (AMD) may be less common in blacks than in whites. A protective effect of melanin has been suggested. The authors analysed 11532 black or white adults, aged 48 to 72 yrs, between 1993 and 1995.
The findings confirm a lower prevalence of AMD among blacks versus whites. No factors were identified that could account for the racial difference in AMD risk.
Dowler JGF, Sehmi KS, Hykin PG,et al (Moorfields Eye Hosp, London)
The Natural History of Macular Edema After Cataract Surgery in Diabetes.
Ophthalmology 106: 663-668, 1999
The natural history of macular edema after cataract surgery was demonstrated in 32 patients who underwent phacoemulsification (cataract) surgey with INTRAOPERATIVE fluorescein angiography. One year follow-up included clinical and angiographic assessment without macular laser treatment.
Clinically significant macular edema occurred in the first year after surgery in 56% of patients. Spontaneous resolution within one year, occurred in 69% of eyes in which it rose during the first 6 months, but in none of the eyes which were affected at the time of surgery. In multivariate analysis, poorer 1-year visual acuity was found in patients with clinically significant macular edema which was present at the time of surgery.
Visual recovery is more likely in patients with mild retinopathy.
Though routine cataract surgery increases the risk of diabetic retinopathy progression, there is likelihood that postoperative cystoid macular oedema (CME) in diabetic eyes will resolve spontaneously over a period of time, if preoperative retinopathy is mild.
Sharma S, Walker R, Brown GC, et al (Queen’s Univ, Kingston, Ont; Wills Eye Hosp, Philadelphia)
The Importance of Qualitative Vitreous Examination in Patients with Acute Posterior Vitreous Detachment.
Arch Ophthalmol 117: 343-346, 1999
Acute posterior vitreous detachment (PVD) which is seen in nearly two-thirds of patients over the age of 69 years, is also a risk factor for retinal tear. Patients with PVD who have abnormal vitreous (viz. Vitreous pigment granules or haemorrhage) have a higher risk of retinal tear.
This article is an analysis of 59 patients with acute PVD, subjected to a multicentric, cross-sectional study in 3 different ophthalmic clinics.
John PM Wood, Dphil; Neville N Osborne, (Nuffield Laboratory of Ophthal, Univ of Oxford, England)
The influence of Zinc on Caspase-3 and DNA Breakdown in Cultured Human Retinal Pigment Epithelial Cells.
Arch Ophthalmol, Jan.2001; 119: 81-88
The authors investigated the role of extracellular zinc on the death process of CULTURED human retinal pigment epithelial (RPE) cells.
It was found that zinc salts protect RPE cells from experimental ischaemia-induced death at low concentrations. However at higher concentrations, zinc causes cell death and alters the cellular level of caspase-3 (a protease enzyme)
The clinical significance is that high concentrations of zinc can damage retinal pigment epithelial cells and hence it is crucial to limit the dose to optimum levels.
P.R. Van Den Biesen, T Berenschot, RM Verdaasdonk et al [ FC Donders Institute of Ophthalmology, Department of Biomedical Engineering, and Institute of Dermatology, University Hospital Utrecht, Utrecht, Netherlands ]
Endoillumination during Vitrectomy and Phototoxicity Thresholds
BJO 2000; 84: 1372-1375
The absolute power and spectral distribution from various light sources and filter combination which are available for vitreous surgery were measured.
The maximal exposure times [based on safety guidelines] for photochemical and thermal injury of the aphakic eye were calculated. The effect of various measures that reduce the risk of photoxicity was evaluated.
Commercially available light sources for endoillumination during vitrectomy are not safe with respect to photochemical retinal damage.
Inspite of maximal precautions macular phototoxic damage remains a factual danger during vitrectomy.
Richard G, Lerche R-C, et al (Univ Hosp Hamburg, Germany)
Treatment of Retinal Arterial Occlusion with Local Fibrinolysis Using Recombinant Tissue Plasminogen Activator
Ophthalmology 106: 768-773, 1999
Forty-six patients with central retinal artery occlusion (CRAO) and seven with branch retinal arterial occlusion were treated for upto 3 hours with 10 to 20mg. recombinant tissue plasminogen activator every hour in 50ml of sodium chloride. The ophthalmic artery was catheterized and the solution was infused transfemorally.
Visual outcome and occlusion time showed no statistically significant correlation, with those who had been treated a few hours after occlusion and those treated more than 20 hours later, having both favourable and unfavourable outcome.
Treatment of retinal ischaemia due to CRAO has been successful only when cell death was prevented and structure maintained by residual perfusion. Videoangiography demonstrated the presence of residual perfusion in Retinal artery occlusion, even when there was clinically apparent retinal oedema, due to rapid formation of collaterals.
Tin K J Chan, Arthur L Rosenbaum, Rajesh Rao, et al (Univ of California, Los Angeles, CA, USA)
Indocyanine green angiography of the anterior segment in patients undergoing strabismus surgery.
Br.J. Ophthalmol. Feb.2001; 85: 214-218.
Imaging of the anterior segment using conventional fluorescein angiography is suitable only in lightly pigmented irides as the brown pigmentation of the iris masks fluorescein transmission.
Indocyanine green (ICG) angiography has excellent penetration of pigment epithelium and hence has potential application in detecting perfusion changes of dark irides after strabismus surgery.
With the advent of digitalized imaging, ICG angiography is useful for studying the choroidal vasculature.
A Sciscio, Anthony G Casswell, (Sussex Eye Hospital, Brighton, UK)
Effectiveness of apraclonidine 1% in preventing intraocular pressure rise following macular hole surgery.
Br. J Ophthalmol. Feb.2001, 85 : 164-168.
Twenty-six eyes (of 25 patients) were studied in a prospective, double masked, randomised study, to compare apraclonidine hydrochloride 1%, an A2 agonist (12 eyes) with a placebo (14 eyes) in the prevention of intraocular pressure (IOP) spikes following macular hole surgery.
Macular hole repair surgery was performed with a vitrectomy, platelet adjunct, and complete fill of the vitreous cavity with perfluoropropane gas (C3F8) at a concentration of 16%.
It was found that apraclonidine hydrochloride 1% was efficacious and safe in the prophylaxis of early IOP spikes in patients undergoing macular hole surgery.
Howard Desatnik, Amir Alhalel, et al ( The Goldschleger Eye Institute, Tel Aviv Univ. Israel )
Management of persistent loculated subretinal fluid after pneumatic retinopexy.
Br J Pphthalmol. Feb.2001, 85: 189-192
Localised, delayed subretinal fluid absorption (DSRFA) is a troublesome complication of pneumatic retinopexy.
This study was a review of patients who underwent pneumatic retinopexy over a 5-year period. Seven phakic patients were indentified having DSRFA. In four patients the subretinal fluid (SRF) involved the macula.
The authors found that DSRFA may persist upto two years. Additional surgical procedures or laser photocoagulation do not affect the rate of SRF absorption.
However, conservative management is indicated as spontaneous reattachment eventually occurs in most eyes.
WW, Dawson, B L Jordan, et al (Univ. of Florida, Gainesville, USA).
Distant cancer effects on standardised testing of peripheral vision
Br.J Ophthalmol, March 2001, 85: 291-296
Standardised tests of peripheral retinal function are often the most sensitive detectors of early eye disease.
Cancer associated retinal deficits (CARD) are common in the retinal periphery of many cancer patients, and are distinct from rare cancer and melanoma associated retinopathies.
There is no identifiable interaction between chemotherapy mode and CARD.
Kerkhoff FT, Rothova A, (Univ Hospital, Utrecht, Netherlands)
Bartonella henselae associated uveitis and HLA-B27
Br.J Opthalmol 2000;84(10):1125-1129.
Bartonella henselae, a Gram negative rod, was identified as the organism causing cat scratch disease (CSD). Ocular involvement in B.henselae infection has been reported to be the cause of Parinaud’s oculo-glandular syndrome, uveitis and neuroretinitis.
The authors have investigated the frequency of HLA-B27 in presumed ocular bartonellosis and have reported the clinical features and laboratory data of these patients.
Miyake K, Ota I, Maekubo, et al (Miyake Eye Hosp, Nagoya, Japan)
Latanoprost Accelerates Disruption of the Blood-Aqueous Barrier and the Incidence of Angiographic Cystoid Macular Edema in Early Postoperative Pseudophakias.
Arch Ophthalmol 117: 34-40, 1999
Latanoprost (prostaglandin F2) lowers intraocular pressure (IOP) by increasing uveoscleral outflow. In human models, latanoprost did not disrupt the blood-aqueous barrier and did not affect cystoid macular oedema (CME) formation in eyes with longstanding pseudophakias.
However, endogenous prostaglandins synthesized in the anterior uvea DO have a role in disrupting the blood-aqueous barrier and in inducing CME after cataract extraction.
In a randomized, double-blind trial for latanoprost, as well as an open-label controlled trial for studying the effects of NSA drops on latanoprost and its place, the authors found that latanoprost disrupts the blood aqueous barrier and increases the incidence of angiographic CME in early postoperative pseduophakia.
Concurrent instillation of NSA drops (e.g. diclofenac) can prevent the adverse effects of latanoprost and thus maintain the decrease in IOP.
AAQ Araujo, AP Wells, AD Dick, JV Forrester (Dept. of Ophthalmology, Aberdeen Royal Infirmary, Aberdeen)
Early treatment with cyclosporin in serpiginous choroidopathy maintains remission and good visual outcome
Br J Ophthalmol 2000; 84: 979-982.
Serpiginous choroidopathy is characterised by geographic areas of choroidal atrophy (in both eyes), which occur around the optic disc and spread in a helicoid pattern along the major vascular arcades towards the macula. Recurrences are common.
Visual disability may result from retinal lesions affecting the central macula, or from secondary choroidal neovascularization due to disruption of the Bruch’s membrane-retinal pigment epithelium.
The authors present a case series of 14 eyes of seven patients with serpiginous choroidopathy with follow up ranging from 1.3 to 13 years.
No patients suffered significant loss of acuity after starting systemic immunosuppression with cyclosporin as the primary agent. There were no serious complications from immunosuppression.
Adequate immunosuppression can result in clinical remission and cessation of therapy in some patients.
M. Uyama, K Takahashi, N Ida, et al ( Department of Ophthalmology, Kansai Medical University, Moriguchi, Osaka, Japan )
The second eye of Japanese patients with unilateral exudative age related macular degeneration.
Br. J. Ophthalmol Sept.2000; 84: 1018-1023
The second eye of unilaterally affected patients with exudative (neovascular) age related macular degeneration (AMD) treated during a 10 year period (1988-1997) were followed up for more than a year.
Evidence of choroidal neovascularization (CNV) was confirmed by fluorescein and indocyanine green angiography.
Macular lesions in patients in whom CNV developed in the second eye, were retrospectively evaluated from patient records.
All 170 patients were Japanese. CNV developed in the second eye in 12 (7%) of these patients, 30.3 months on average after the first examination.
CNV in the second eye was found to be relatively low compared with that in white patients. CNV usually developed from serous pigment epithelial detachment (PED) in the macula (58%). Soft drusen were not prevalent and the risk of developing CNV was not very high (18%).
CF Parsa, JR EW Cheeseman, IH Maumenee (Johns Hopkins Hosp, Baltimore, Md)
Demonstration of Exclusive Cilioretinal Vascular System Supplying the Retina in Man: Vacant Discs.
Trans Am Ophthalmol soc 96: 95-109, 1998.
Eyes with a combined cilio-retinal arterial and venous supply have NO vessels in the central part of the retina; all vessels enter and leave the disc peripherally. An exclusive ciliary vascular supply of the retina is rare. These authors reported the first case of exclusive cilioretinal vessels confirmed by fluorescein angiography and Doppler US.
The central retinal vessels were completely absent in both eyes; the retina was supplied exclusively by ciliary blood flow. Past authors have labeled these discs as atypcial colobomas – but in colobomatous anomalies, the central vessels are displaced superiorly whereas in the present case the central vessels were dysplastic i.e. completely absent.
ML Klein, DW Schultz, A Edward, et al (Oregon Health Sciences Univ, Portland; The Rockefeller Univ, New York)
Age Related Macular Degeneration: Clinical features in a Large Family and Linkage to Chromosome 1q.
Arch Ophthalmol 116: 1082-1088,1 998.
Evidence suggests genetic influences in the pathogenesis of age-related macular degeneration (AMD). In a large family of 21 members, ten were found to be affected by AMD which was characterized by large soft, confluent drusen and varying degrees of retinal pigment epithelial degeneration and/or atrophy. The disease segregated as an autosomal dominant trait.
In this family the lesion was localised to chromosome 1q25-q31. Identifying AMD genes can facilitate early diagnosis and improve the understanding of the molecular pathophysiology of AMD.
RF Spaide, DR Guyer, B McCormick, et al (Manhattan Eye, Ear , and Throat Hosp, NY; Mem Sloan Kettering Cancer Ctr, New York)
External Beam Radiation therapy for Choroidal Neovascularization.
Ophthalmology 105: 24-30, 1998
The effect of external beam radiation treatment on Choroidal Neovascularisation (CNV) caused by AMD was studied.
It was found that external beam radiation of 1000 cGyin 5 fractions is NOT effective in patients with CNV caused by AMD. This dose which was used in previous studies, should NOT be given in trying to treat such patients.
B Lindblom, T Anderson (Goteborg, Sweden):
The Prognosis of Idiopathic Choroidal Neovascularization in Persons Younger Than 50 Years of Age.
Ophthalmology 105: 1816-1820, 1998.
For eyes with choroidal membranes associated with AMD, the prognosis of idiopathic CNV was much better than previously reported. Conservative regime of treatment is preferred to argon laser photocoagulation.
NJ Christmas, WE Smiddy, Jr HWFlynn, (Univ of Miami, Fla)
Reopening of Macular Holes After Initially Successful Repair.
Ophthalmology 105: 1835-1838, 1998.
The anatomical success rate of vitreous surgery for a macular hole is more than 90%. Half the patients recover at least 20/40 (6/12) visual acuity. Reopening of the hole has been reported in about 5% of patients, though visual acuity usually continues to improve after successful macular hole surgery. It is rare to see reopening of a macular hole associated with cataract surgery. The exact mechanism of reopening of the hole is not known, but may relate to mechanical or inflammatory factors.
NE Byer (Univ of California, Los Angeles)
What Happens to Untreated Asymptomatic Retinal Breaks, and Are They Affected by Posterior Vitreous Detachment?
Ophthalmology 105:1045-1050, 1998.
Asymptomatic, unsuspected retinal breaks are common. In this large study of 235 eyes, patients were studied without treatment, for an average of 11 years. All patients had clinical follow up, including binocular indirect ophthalmoscopy with scleral indentation.
The combined risk of retinal detachment requiring treatment was only 1% to 2%. Posterior vitreous detachment has NO adverse effect on the outcomes of pre-existing retinal breaks.
Therefore, prophylactic treatment of retinal breaks is NOT required before or after the development of posterior vitreous detachment.
BP Connolly, JA McNamara, S Sharma, et al (Jefferson Med College, Philadelphia).
A Comparison of Laser Photocoagulation with Trans-scleral Cryotherapy in the Treatment of Threshold Retinopathy of Prematurity.
Ophthalmology 105: 1628-1631, 1998.
Laser photocoagulation (LPC) appears to be superior to transcleral cryotherapy for the treatment of threshold retinopathy of prematurity (ROP). In this series, visual acuity was better and myopia was less after LPC than after cryotherapy.
AK Tyagi, S Scotcher, N Kozeis, et al (Birmingham and Midland Eye Centre, England; Birmingham Children’s Hosp., England) Can Convulsions Alone Cause Retinal Haemorrhages in Infants?
Br J Ophthalmology 82:659-660, 1998
Convulsions alone are unlikely to cause retinal haemorrhages in children younger than two years. When retinal haemorrhages are seen in very young children admitted after convulsions, it is important to search for other causes for the haemorrhages, especially nonaccidental injury.
PL Fritsche, E.Flipsen, et al (Univ. Hospital Vrije Unviersiteit, Dept. of Ophthalmology, De Boelelaan, Netherlands)
Subretinal Hemorrhage From Retinal Arterial Macroaneurysm Simulating Malignancy.
Arch Ophthal, Vol.118, Dec.2000, pp.1704.
This is an interesting case report with photographs of a large macroaneurysm seen in the right superotemporal region in relation to the optic disc, which could be mistaken for a melanoma.
The authors describe a female preponderance and an association of this condition with systemic hypertension, diabetes mellitus and cardiovascular disease.
They recommend meticulous fundoscopy, fluorescein angiography, ultrasonography and prolonged observation to avoid mistaken diagnosis.
H.V. Danesh-Meyer, P J Savino et al (Wills Eye Hospital, Philadelphia)
Ocular and cerebral ischemia following facial injection of autologous fat
Arch.Ophthalmol, vol.119, May 2001, p.777-778
Multiple anastomoses between the vascular supply of the face and orbit exist. With increasing frequency of periocular and paranasal injections of various substances the potential for retrograde embolization exists.
The authors report a case of paranasal autologous fat injection resulting in middle cerebral, ophthalmic artery and central retinal artery occlusion. A 43-year male received an injection of autologous fat in the tissue on the left side of the bridge of his nose to repair a soft tissue defect, a result of a previous accident.
Within 10 minutes post injection, he complained of eye and head pain, became disoriented and lost vision of the left eye. He also developed aphasia with right- sided hemiparesis. The left fundus showed a clinical picture of central retinal artery occulsion.
T Murata, Y Hata, et al (Keck School of Medicine of Univ. of Southern California)
Response of Experimental Retinal Neo-Vascularization to Thiazolidinediones
Arch Ophthal, vol.119, May 2001, p.709- 717.
The ability of the thiazolidinediones (TZDs) troglitazone and rosiglitazone maleate to inhibit retinal endothelial cell proliferation, migration, tube formation and signaling was determined in response to vascular endothelial growth factor (VEGF).
It was found that TZDs inhibit experimental retinal neovascularization.
TZDs which are widely prescribed should be evaluated for their potential to inhibit the progression of diabetic retinopathy.
Thomas A Ciulla (Indiana Univ.School of Med, Indianapolis)
Evolving patho-physiological paradigms for age related macular degeneration
Br J Ophthal. Vol.85, May 2001, p.510-512
Several theories regarding the pathogenesis of ARMD (age related macular degeneration) have been discussed.
Primary retinal pigment epithelium (RPE) and Bruch’s membrane senescence, oxidative injury, primary genetic defects and primary ocular perfusion abnormalities have all (singly or together) been mentioned as factors contributing to the pathogenesis of ARMD.
M R Beintema, J A Oosterhuis, et al (Univ. Eye Dept. Maashicht, Netherlands)
Yellow dye laser thermotherapy of choroidal neovascularisation in age related macular degeneration.
Br J Ophthal, June 2001; 85: 708-713.
This is a pilot study of the feasibility of using dye laser thermotherapy (LTT) at a subcoagulation temperature to occlude newly found vessels in patients with age related macular degeneration (AMD).
24 eyes with exudative AMD were treated with a continuous wave yellow laser. The effect of thermotherapy was documented by ophthalmoscopic and fluorescein angiographic examintion. Mean follow up was 5 months.
Total occlusion of newly formed vessels was achieved in 15 eyes (62.5%). Recurrences 2-4 months after LTT were seen in three eyes.
The authors conclude that CNV in AMD can effectively be treated by yellow dye laser thermotherapy with preservation of choroidal perfusion.
KG Schmidt, LE Pillunat et al (Nuffield Lab. of Ophthal, Walton Street, Oxford, UK)
Ocular pulse amplitude is reduced in patients with retinitis pigemntosa.
Br. J. Ophthal, June 2001; 85: 678-682.
The aim of this study was to determine whether there is reduction of choroidal perfusion in retinitis pigmentosa (RP) and whether there is any correlation with the stage of disease.
Ocular pulse amplitude (OPA) evaluated with the ocular blood flow (OBF) system, applanation tonometry, visual fields, blood pressure and heart rate were measured in 75 RP patients and compared with matched healthy controls.
It was found that neither intraocular pressure nor systemic perfusion parameters were significantly altered, but OPA in RP patients was significantly reduced when compared with matched subgroups from a pool of healthy controls.
The authors conclude that in advanced stages of RP not only the retina but also the choroidal circulation is affected.
E McLoone, G Mahon, et al (Queen’s Univ. of Belfast, U.K.)
Silicone oil-intraocular lens interaction: which lens to use ?
Br J Ophthal, May 2001: 85: 543-545
PMMA, AcrySof, AR40, AQUA-Sense and Raysoft lenses were examined. Each lens was immersed for 5 minutes intervals in balanced salt solution (BSS) in stained silicone oil, and again in BSS before being photographed in air and in BSS. Percentage of silicone oil coverage of the lens optic was compared.
The authors found that a Raysoft lens was a suitable lens in patients who are at risk of vitreo-retinal disease.
M Minihan, V Tanner, T H Williamston (St. Thomas’s Hospital, London, UK)
Primary rhegmatogenous retinal detachment: 20 years of change.
Br. J Ophthal, May 2001; 85: 546-548.
Though surgical management of primary rhegmatogenous retinal detachment has changed greatly in 20 years, the authors found little change in success rates despite the availability of different surgical procedures.
This was a comparative study between 124 patients operated in 1979-80, and 126 cases operated in 1999.
S C Lee, E T Lee et al (Univ. of Oklahoma)
Comparison of Diagnosis of Early Retinal Lesions of Diabetic Retinopathy Between a Computer System and Human Experts.
Arch.Ophthalmol, April.2001. vol.119, p.509-515
Color fundus photographs were used to investigate whether a computer vision system is comparable with humans in detecting early retinal lesions of diabetic retinopathy. It was found that the performance of the computer vision system was comparable with human experts.
The authors conclude that the mobile, electronically easily accessible and non-invasive computer system, could become a mass screening tool and a clinical aid in diagnosing early lesions of diabetic retinopathy.
MF Marmor (Stanford Univ.School of Medicine, Standford, Calif.)
Double Fault !
Ocular Hazards of a Tennis Sunglass.
Archives of Ophthalmology, vol.119, July 2001: 1064-65
Though blue-tinted lenses are used by tennis players with expectations of better performance, and safety in sunlight, the author argues that BLUE lenses are not only ineffective with respect to visual performance on most tennis courts (except red or amber coloured), but also pose a potential hazard to the eyes. This hazard is because of the fact that both near -UV and visible blue light may contribute to macular aging and degeneration.
Blue light in general is less effective physiologically with respect to functions such as acuity, contrast detection and motion perception.
For tennis players, wearing a cap with a visor will reduce glare and make the court appear relatively brighter.
R Tokai, T. Ikeda, et al (Hyogo College of Medicine Hyogo, Japan)
Interferon-Associated Retinopathy and Cystoid Macular Oedema.
Arch.Ophthal, vol.119, July 2001, pp.1077-79
The authors describe the first patient with interferon-associated retinopathy (usual findings – retinal haemorrhages and cotton-wool spots) who developed decreased visual acuity due to bilateral cystoid macular oedema (CME).
In this case, bilateral retinopathy worsened 11 days after cessation of interferon treatment and vision dropped to 20/40.
Thirty-three days after termination of interferon therapy, the CME disappeared and vision recovered to 20/20.
The authors mention atypical interferon-associated ocular complications viz. oculomotor nerve paralysis, optic disc oedema, subconjunctival, preretinal, and vitreous haemorrhage; and retinal vein occlusion.
H Jackson, D Garway-Health et al (Institute of Ophthalmology, Cayton street, London)
Outcome of cataract surgery in patients with retinitis pigmentosa.
B.J.O. Aug.2001; 85: 936-938
This retrospective analysis was undertaken of a continuous series of 142 eyes of 89 patients with retinitis pigmentosa undergoing cataract surgery.
The authors conclude that cataract surgery for relatively minor lens opacities is beneficial in patients with retinitis pigmentosa. Majority of patients report subjective improvement of visual symptoms. The incidence of capsular opacification is high. The incidence of postoperative macular oedema was unexpectedly low.
C Luke, S Aisenbrey, M Luke, et al (Zentrum fur Augenheilkunde, Universitat Koln, Germany)
Electrophysiological changes after 360° retinotomy and macular translocation, for subfoveal choroidal neovasuclarisation in age related macular degeneration
B.J.O. Aug.2001; 85: 928-932
Macular translocation may provide the potential of preserving and restoring vision in patients with subfoveal choroidal membranes secondary to age related macular degeneration (AMD).
However the above study indicates that a significant electrophysiological decrease is caused by the surgical procedures associated with this technique.
Further research is required to clarify if modifications of the surgical procedure are able to reduce the neuroretinal trauma.
A. Assi, S Woodruff, et al (Moorfields Eye Hosp., London)
Combined phacoemulsification and transpupillary drainage of silicone oil: results and complications.
B.J.O. Aug.2001; 85: 942-945
The authors have analyzed 74 consecutive cases of combined phacoemulsification and transpupillary drainage of silicone oil. They conclude that combined phacoemulsification and transpupillary drainage of silicone oil is a safe and reliable technique offering the advantage of diminished surgical trauma.
A.D.Dick, V.Sharma et al (Univ. of Aberdeen, U.K)
Single dose intranasal administration of retinal autoantigen generates a rapid accumulation and cell activation in draining lymph node and spleen: implications for tolerance therapy.
B.J.O. Aug.2001; 85: 1001-1006
A single intranasal delivery of retinal autoantigen suppresses experimental autoimmune uveoretinitis (EAU).
Flow cytometry, cell proliferation assays and microscopy were used to track antigen following a single, intranasal dose of Alexa-488 labelled retinal antigen.
After 30 minutes, a rapid accumulation of antigen was found within both superficial cervical lymph nodes (SCLN) and spleen.
The authors conclude that following a single intranasal application, rapid transfer of antigen occurs. T cell proliferation develops consequent to differential cell signalling in SCLN and spleen.
These observations may assist in strategies to clinically apply mucosal tolerance therapy successfully.
G Mannino, R Malagola, et al (Univ. of Rome, “La Sapienza”, Rome, Italy)
Ultrasound biomicroscopy of the peripheral retina and the ciliary body in degenerative retinoschisis associated with pars plana cysts.
Br.J.Ophthal, August 2001; 85: 976-982
18 eyes of 12 patients with degenerative retinoschisis, and pars plana cysts were selected for study through binocular indirect ophthalmoscopy, and Goldmann three mirror lens examination. All patients were studied in detail with the ultrasound biomicroscope (UBM).
A close relation of the cysts with the region of the ora serrata and peripheral retina was observed, along with areas of cystoid degeneration and retinoschisis.
UBM allowed differentiation between retinoschisis and associated retinal detachment in six eyes.
J M Seddon, B Rosner et al (Massachusetts Eye and Ear Infirmary, Boston MA)
Dietary Fat and Risk for Advanced Age-Related Macular Degeneration
Arch Ophthalmol Vol. 119, August 2001 Pg. 1191-1199
This is a multicenter case control study at 545 clinical Ophthalmology centers.
Case subjects were 349 patients (age 55-80 years) with advanced neovascular stage of age-related macular degeneration (AMD) diagnosed within one year of their enrollment into the study.
It was found that higher intake of specific types of fat – including vegetable, monounsaturated and polyunsaturated fats and linoleic acid – rather than total fat intake may be associated with a greater risk for advanced AMD.
Diets rich in w-3 fatty acids and fish were inversely related to the risk for AMD when intake of linoleic acid was low.
Cryotherapy for Retinopathy of Prematurity Cooperative Group
Mutlicenter Trial of Cryotherapy for Retinopathy of Prematurity
Arch Ophthal, vol.119, August 2001; p.1110-1118
This was a randomized cohort study of 291 preterm children with birth weight less than 25gms, who developed a defined threshold of Retinopathy of prematurity (ROP) severity in one or both eyes.
Patients were randomly assigned to receive cryotherapy to one eye and no cryotherapy to the other.
At 10 years of age, eyes that had received cyrotherapy were much less likely than control eyes to be blind.
A previous view about a higher proportion of sighted control eyes than sighted treated eyes to show better acuity was not confined.
The results confirm the long-term value from cyrotherapy in preserving visual acuity in eyes with threshold ROP.
Yasuko Noda, Mitsuru Nakazawa, Daisuke Takahashi, Tomoko Tsuruya, Makoto Saito (Department of Ophthalmology, Hirosaki University School of Medicine, Hirosaki)
Retinal Periphlebitis as Zoster Sine Herpete
Arch Ophthalmol. Vol. 119(10), October 2001; Pg. 1550-1552
Infection with varicella-zoster (VZV) has been known to cause occlusive retinal arteritis leading to acute retinal necrosis. However, retinal periphlebitis is a rare manifestation of varicella-zoster ophthalmicus.
Two cases of retinal periphlebitis have been described, without preceding symptoms or herpes cutaneous eruptions.
The ophthalmic manifestations included: unilateral raised intraocular pressure; iridocyclitis; retinal periphlebitis without retinal exudates, hemorrhages, or periarteritis; diffuse vitreous opacity; positive VZV genome in the aqueous humor; and iris atrophy.
Age-Related Eye Disease Study Research Group
AREDS Report No. 8
A Randomized, Placebo-Controlled, Clinical Trial of High-Dose Supplementation With Vitamins C and E, Beta Carotene, and Zinc for Age-Related Macular Degeneration and Vision Loss
Arch Ophthalmol. Vol. 119(10), October 2001; Pg. 1417-1436
Anti-oxidant and/or zinc supplements may delay progression of age-related macular degeneration (AMD) and visual loss.
An 11-center double-masked clinical trial, enrolled participants in an AMD trial if they had extensive small drusen, intermediate drusen, large drusen, noncentral geographic atrophy, or pigment abnormalities in 1 or both eyes, or advanced AMD or visual loss due to AMD in 1 eye.
3640 enrolled participants, aged 55-80 years were randomly assigned to receive daily oral tablets containing (1) antioxidants (vitamin C, 500 mg; vitamin E, 400 IU; and beta carotene, 15 mg); (2) zinc, 80 mg, as zinc oxide and copper, 2 mg, as cupric oxide; (3) antioxidants plus zinc; or (4) placebo. Average follow-up was 6.3 years.
Comparison with placebo demonstrated a statistically significant odds reduction for the development of advanced AMD with antioxidants plus zinc.
The only statistically significant reduction in rates of at least moderate visual acuity loss occurred in persons assigned to receive antioxidants plus zinc.
F. Segev, A. Segev, et al (Department of Ophthalmology, Meir Hospital, Israel)
Bilateral Central Retinal Vein Occlusion in a Patient With Occult Colon Cancer
Arch Ophthalmol., October 2001, Vol. 119(10) Pg. 1552-1553
This is a case report of a 78-year old male patient who developed simultaneous bilateral central retinal vein occlusion.
The patient complained of acute bilateral visual loss lasting for several days.
Apart from a high E.S.R. and elevated carcino embryonic antigen, laboratory investigations were normal.
Colonoscopy revealed a nearly obstructive tumor mass in the sigmoid colon.
The authors state that this is the first case report of simultaneous bilateral central retinal vein occlusion, associated with carcinoma.
K. A. V. O.verdam, J. C. V. Meurs, et al (Rotterdam Eye Hospital, Schiedamse Vest 180, Rotterdam, the Netherlands)
Symptoms Predictive for the Later Development of Retinal Breaks
Arch Ophthalmol., October 2001, Vol. 119(10) Pg. 1483-1486
280 consecutive patients who had symptoms of posterior vitreous detachment were prospectively asked to complete a questionnaire detailing their symptoms. They were reexamined 6 weeks following onset of symptoms. However, if small retinal or vitreous hemorrhages were detected patients were reexamined after 2 weeks.
A retinal break was detected at reexamination in 13 patients (5.2%). Symptoms of flashes of light in combinations with clouds or multiple small dots at the time of the INITIAL examination, or an increase of floaters after the initial examination were statistically significantly related to the development of new retinal breaks.
These symptoms had a predictive value for the presence or absence of a new retinal break of 75% and 99.6% respectively.
C. A. McCarty, B. N. Mukesh et al (Centre for Eye Research Australia, University of Melbourne, East Melbourne and Save Sight Institute, University of Sydney)
Risk Factors for Age-Related Maculopathy
The Visual Impairment Project
Arch Ophthalmol., October 2001, Vol. 119(10) Pg. 1455-1462
Residents were recruited from 9 randomly selected urban clusters and 4 randomly selected rural clusters (from Victoria, Australia).
The following information was collected: Visual acuity, medical and health history lifetime sunlight exposure, dietary intake and fundus photographs.
The authors conclude that smoking is the only modifiable risk factor for ARM (age-related maculopathy) and AMD (age-related macular degeneration), among the various environmental and system factors, which were assessed.
Eller AW, Friberg TR, Mah F (Univ.of Pittsburgh, Pa)
Migration of Silicone Oil Into the Brain: A complication of Intraocular Silicone Oil for Retinal Temponade
Am J Opthalmol 129: 685-688, 2000
The authors report, migration of silicone oil into the brain, in a man aged 42 yrs suffering from progression of AIDS and cytomegalovirus retinitis.
The retinitis became resistant to gancyclovir. Later foscarnet injections were used and after 2 months he developed a total retinal detachment which was operated upon.
Pars plana vitrectomy, pars plana lensectomy, gas-fluid exchange, endolaser photocoagulator and placement of silicone oil were performed.
Postoperatively (after 2 months) there was no light perception, in the operated eye and IOP was 44mm Hg.
Symptoms of peripheral neuropathy, including paresthesia of distal extremities developed.
MRI and CT showed focal globular abnormalities, intracranially, whose MRI appearance resembled that of silicone oil in his left eyeball. The material shifted on repetition of the MRI with the patient prone.
The authors postulate that in the presence of high IOP, silicone oil used intraocularly may be able to migrate along the tract of the optic nerve into the lateral ventricles of the brain.
Maintenance of control of IOP may prevent this complication.
Marsh S, Miller BP, Nakhoul FM, et al (Rambam Med Ctr, Haifa, Israel; Technion-Israel Inst of Technology, Haifa)
Hypoxic Induction of Vascular Endothelial Growth Factor is Markedly Decreased in Diabetic Individuals Who Do Not Develop Retinopathy.
Diabetes Care 23: 1375-1380, 2000
Prevalence and severity of non-proliferative and proliferative diabetic retinopathy (DR) are related to age of onset, type and duration of diabetes and level of glycemic control.
Vascular endothelial growth factor (VEGF) has been shown to play a major role in the development of DR as a result of retinal ischemia and hypoxia.
The relationship of VEGF response to hypoxia in monocytes harvested from diabetes patients and of presence or absence of DR was analysed.
The authors conclude that diabetic patients who were low inducers of VEGF with hypoxia were significantly less likely to show evidence of DR, even after 2 decades. Why individuals differ in their hypoxic induction of VEGF is yet undetermined.
Ozaki H, Seo M-S, et al (Johns Hopkins Univ, Baltimore, Md; Novartis Ltd Pharmaceuticals Inc, Basel, Switzerland)
Blockade of Vascular Endothelial CE Growth Factor Receptor Signaling Is Sufficient to Completely Prevent Retinal Neovascularization
Am J Pathol 156:697-707, 2000
Vascular endothelial cell growth factor (VEGF) plays an important role in the pathogenesis of retinal vasculogenesis and the development of retinal neovascularization (NV) in ischemic retinopathies.
Insulin-like growth factor I, and other growth factors may also play a role in the development of retinal NV.
The authors investigated the signaling pathways involved in retinal NV.
PTK 787 (a kinase inhibitor) blocks phosphorylation by VEGF and platelet derived growth factor (PDGF) receptors and was found to completely inhibit retinal NV in MURINE retinal vascularization during development.
Murata T, Cui J, et al (Univ. of Southern California, Los Angeles; Kyushu Univ, Fukuoka, Japan)
The Possibility of Gene Therapy for the Treatment of Choroidal Neovascularization.
Ophthalmology 107: 1364-1373, 2000
The potential of ex vivo and in situ gene therapy for choroidal neovascularization (CNV) was investigated.
In the first experiment, transduced human retinal pigment epithelium (RPE) cells with a retroviral vector coding for b-galactosidase, were grown on type II collagen sheets and then transplanted under the retina of rabbits, where they were left for 3 to 56 days before histological examination and X-gel staining.
In the second experiment, bovine choroidal endothelial cells were transduced with retroviral vectors coding for tissue inhibitor of metalloproteinase-2 (TIMP-2).
In both experiments, after technical success of transplantation, (rate was 50% in first experiment), the response was assessed after 12 weeks with fluorescein angiography.
The results demonstrated survival of transduced RPE cells in the subretinal space, with continued expression of the coded gene product for at least 2 weeks. Choroidal endothelial cells can be transduced to produce TIMP-2, with a reduced angiogenic response.
Robertson DM, Lim TH, et al (Mayo Clinic, Rochester, Minn)
Laser Pointers and the Human eye: A Clinicopathologic Study
Arch Ophthalmol 118; 1686-1691, 2000
A laser beam from a class 3A red diode laser pointer was directed through a 5mm hole in the center of a black Amsler grid, through the pupil onto the retina of 3 patients all of who had uveal melanomas and were scheduled for enucleation. The fovea was exposed continuously for 1 minute.
The retina was exposed at 5 degrees below fixation for 5 minutes and at 5 degrees above fixation for 15 minutes. Two patients reported pink vision for 2 to 3 minutes after laser light exposure. However, no functional visual or histologic damage was found in any of the eyes.
Flaxel CJ, Mulholland B, et al (Moorfields Eye Hosp, London; Inst of Cancer Research, Sutton, Surrey, England)
Intraocular Penetration of Tamoxifen
Ophthalmology 107: 2006-2009, 2000
In 1978, tamoxifen keratopathy and retinopathy were reported in women receiving very high doses.
Recent studies have found tamoxifen induced optic neuritis. The authors compared the levels of the drug in aqueous, vitreous and serum after ocular penetration by oral tamoxifen was documented.
Tamoxifen levels were estimated in serum of all patients before surgery, in aqueous humor of patients posted for cataract surgery and in the vitreous humor of patients having pars/plava vitrectomy.
The authors postulate that tamoxifen may exert its toxicity on the retinal pigment epithelium (RPE). The toxicity seems to be dose related rather than due to idiosyncracy.
Retinopathy or keratopathy or both developing in patients receiving low doses of tamoxifen, may be because of more susceptible RPE and lysosomes, due to which tamoxifen is deposited in the nerve fiber layer more rapidly.
Madhavan H, Therese KL, et al (Vision Research Found, Sankara Nethralaya, Chennai, India)
Polymerase Chain Reaction for Detection of Mycobacterium tuberculosis in Epiretinal Membrane in Eales’ Disease
Invest Opthalmol Vis Sci 41: 822-825, 2000
A nested polymerase chain reaction (nPCR), which detects the MPB64 gene of mycobacterium tuberculosis, was applied to archival specimens of epi-retinal membrane (ERM) of patients with well documented cases of Eales and non-Eales’ disease.
The nPCR technique was standardized and applied to tissue sections obtained from formalin fixed and paraffin embedded ERM material from 23 patients with Eales disease and 27 with non-Eales.
This technique was specific for Mycobacterium tuberculosis. Positive results for Mycobacterium tuberculosis genome were found in 41.8% of the group with Eales, while they were found in 11.1% of the control group. The authors believe this difference to be significant.
Gross RL, Hensley SH, Gao F, et al (Baylor College of Medicine, Houston)
Effects of Betaxolol on Light Responses and Membrane Conductance in Retinal Ganglion Cells.
Invest Ophthalmol Vis Sci 41: 722-728, 2000
The physiologic effects of betaxolol on retinal ganglion cells were investigated, and its potential to elicit neuroprotective response against retinal cell degeneration was determined, in an experiment where living retinal slice preparations of the larval tiger salamander were studied.
The authors postulate that betaxolol prevents retinal ganglion cell death induced by increased extracellular glutamate or by increased spontaneous spike rates under pathologic conditions.
Physiologic actions of betaxolol result in a decrease in neurotoxic effects in ganglion cells, which are most susceptible to glutamate-induced damage under ischemic and glaucomatous conditions.
C I Falkner, S Binder, A Kruger (Rudolf Foundation Clinic, Vienna, Austria)
Outcome after silicone oil removal
BJO, 2001: 85: 1324-1327
Silicone oil injection combined with vitreoretinal surgery, has become a standard technique and improves the prognosis of complex retinal detachment.
115 consecutive cases of silicone oil removal all operated by one surgeon, were analysed. Of these 103 eyes had retinal detachment (RD) with proliferative vitreoretinopathy, 6 had RD with proliferative diabetic retinopathy and 6 had RD associated with ocular trauma.
The mean duration of silicone oil (SO) tamponade was 13.3 months. Mean post-operative follow up was 1.8 years.
Anatomic success after S.O. Removal was achieved in 82.6% eyes. Redetachment occurred in 17.4%, mostly within 6 months of S.O. Removal.
Including the successfully reoperated eyes, the authors present a final anatomic success of 93.9%. Visual acuity improved or remained unchanged in 80.9% eyes.The duration of S.O. Tamponade had no significant effect on reattachment rate.
The authors feel that criteria for the timing of S.O. Removal should be decided per individual patient.
N Karia, A Laidlaw et al (Moorfield’s Eye Hosp, London)
Macular hole surgery using silicone oil tamponade.
BJO, Nov.2001, 85(11): 1320-23
A series of patients who underwent macular hole surgery using silicone oil without any postoperative posturing, were reviewed.
Ten eyes of 10 patients underwent surgery,where duration of oil tamponade ranged 3-9 months.
The macular hole was found closed in 8 eyes (80%), following oil removal. Out of these, only 3 showed improvement in visual acuity even after cataract extraction (38%).
All eyes developed cataract to varying degrees. One eye developed raised IOP which settled after oil removal. Endophthalmitis occurred in one eye following removal of sutures after cataract extraction.
Though anatomical results (80%) are in keeping with those reported in other studies using gas tamponade, visual results are disappointing and less rewarding than those obtained after successful surgery using gas tamponade.
Peter R Simcock, Sergio Scalia (Royal Devon and Exeter Hospital, UK)
Phacovitrectomy without prone posture for full thickness macular holes.
BJO, Nov.2001, 85(11); 1316-19
The authors discuss the role of phaceovitrectomy surgery without prone posture for stage 2 and 3 macular holes.
A pilot study was performed on 20 patients (20-eyes) having phacoemulsification lens removal and vitrectomy with 20% C2F6 tamponade.
Anatomical closure of the macular hole was seen in 18 of 20 eyes.
Vitrectomy with internal tamponade of the hole is considered essential for successful hole closure.
However, there is debate, about the type of tamponading agent and the need for and duration of prone posturing.
There is no consensus on the need for internal limiting membrane peeling.
Combining the surgery (cataract extraction, vitrectomy and tamponade) has many advantages both for the surgeon and the patient.
Aphakia combined with a wide angle viewing system enables excellent visibility during posterior vitreous peeling and peripheral gel removal. Peripheral retinal tears (during vitrectomy) can be easily recognised. Good visibility (due to aphakia) facilitates a more complete vitrectomy.
Macular holes close without posture when oil is used as a tamponading agent. A gas fill however creates a greater tamponade on the macula compared with an equivalent oil fill because of its greater buoyancy.
Internal limiting membrane (ILM) peeling has been advocated to improve hole closure.
Nils-Claudius Gellrich, Ronald Schimming, Martin Zerfowski et al (Univ of Freiburg, Germany)
Quantification of histological changes after calibrated crush of the intraorbital optic nerve in rats.
Br.J.Ophth. February, 86: 233-237
Traumatic optic nerve lesions (TONL) are a probable and unpredictable result of severe midface or skull base trauma.
The authors developed a rat model to simulate optic nerve crush during trauma to the optic canal.
To achieve this aim, a microinjuring device was designed to assess the correlation between a defined trauma and the neuronal degeneration in the rat retinal ganglion cell (RGC) layer.
The authors feel that this model provides a reliable method for studying quantitatively the anatomical effects of TONL on the RGC layer and the optic nerve.
Mona Pache, Peter Meyer, Christian Prünte, et al (Univ. Eye Clinic, Basel, Switzerland)
Sildenafil induces retinal vasodilatation in healthy subjects.
BJO, February 2002, vol.86: 156-158
The authors evaluated the effect of a single dose administration of Sildenafil on the retinal vessel diameters of healthy subjects. 50mg Sildenafil was administered to 10 healthy subjects. Diameters of retinal arteries and veins were measured by a retinal vessel analyzer, immediately before and at 30, 60,90 and 120 minutes after sildenafil uptake.
Blood pressure, heart rate and IOP were monitored.
30 minutes after Sildenafil uptake, a significant increase of 5.8% in both retinal arterial and venous diameter, was observed.
Diameters returned to baseline after 120 minutes. Changes in heart rate and IOP were not seen.
H Funatsu, H Yamashita, Y Nakanishi, S Hori (Dept. of Ophth, Diabetes center)
Angiotensin II and vascular endothelial growth factor in the vitreous fluid of patients with proliferative diabetic retinopathy.
BJO, March 2002, 86(3), pg.311-315
During vitreoretinal surgery, vitreous fluid samples were taken from 51 eyes of diabetic patients with proliferative diabetic retinopathy (PDR), 6 eyes of diabetic patients without retinopathy and 16 eyes of non-diabetic with ocular disease (controls).
The vascular endothelial growth factor (VEGF) levels in vitreous fluid and plasma were determined by enzyme linked immunosorbent assay. Angiotensin II levels were measured by radio-immunoassay.
It was found that both angiotensin II and VEGF levels were significantly higher in the vitreous fluid of patients with PDR, than in non-diabetic patients or diabetic patients without retinopathy.
The above findings suggest that angiotensin II contributes to the development and progression of PDR (in combination with VEGF).
S Boyd, D Owens, et al (Moorfields Eye Hosp, London, UK)
Plasma Homocysteine Methylene Tetrahydrofolate Reductase C677T and Factor II G20210A Polymorphisms, Factor VIII, and VWF in Central Retinal Vein Occlusion
BJO. Nov.2001, 85(11): 1313-1315
63 consecutive patients with central retinal vein occlusion and 63 age matched controls were compared to determine whether plasma homocysteine, methylene tetrahydrofolate reductase (MTHFR) C677T and factor II G20210A polymorphisms factor VIII and VWF are risk factors for central retinal vein occlusion (CRVO).
Plasma levels were not statistically higher in patients than in controls.
Hence, this study has not identified new risk factors for CRVO.
J Lee, Sanjay Logani, et al (N. W. Univ Med School, Chicago)
Preretinal Neovascularisation Associated with Choroidal Melanoma
BJO, Nov.2001, 85(11): 1309-1312
The authors report 3 cases of choroidal melanoma with the very rare finding of overlying pre-retinal neovascularisation (NVE).
All 3 patients had choroidal melanomas, localized serous retinal detachment and NVE.
Two cases showed definite retinal capillary non-perfusion. One of these two patients showed retinal telangiectasis.
One patient’s melanoma responded quickly to iodine-125 plaque radiotherapy but retinal neovascularization persisted and caused vitreous hemorrhage.
Scatter photocoagulation was successful in causing the complete regression of neovascularization.
The other 2 patients had their eyes enucleated, and in one of the cases preretinal vessels were seen in histological sections.
Possible aetiologies of pre-retinal neovascularization include (i) release of tumor angiogenic factors (ii) inflammation (iii) chronic retinal detachment with secondary retinal ischemia (iv) retinal vascular occlusion secondary to retinal vessel invasion by the tumor or (v) following radiation therapy.
J.M. Ruiz-Moreno, C. de la Vega (Dept. of Ophth. Univ.School of Medicine, Alicante, Spain)
Surgical removal of subfoveal choroidal neovascularisation in highly myopic patients.
BJO, 2001; 85:1041-1043.
Twenty-two eyes of patients with high myopia (>-6 Dioptres) with subfoveal choroidal neo-vascularisation (CNV) treated by vitrectomy and surgical extraction of the CNV were analysed retrospectively. The patient’s mean age was 60.27 years.
The authors found NO significant improvement of best corrected visual acuity after this procedure.
UEK Schnurrbusch, K Welt et al (Leipzig, Germany)
Histological findings of surgically excised choroidal neovascular membranes after photodynamic therapy.
BJO, 2001: 85: 1086-91
Two patients with recurrences after photodynamic therapy (PDT) with verteporfin underwent surgical removal of the choroidal neo-vascular membrane (CNVM).
After surgery, the subfoveal CNVMs were divided for processing by (a) light microscope (b) electron microscope.
Microscopic findings suggested that evidence of fluorescein leakage from the CNVM and enlargement of the neovascular complex following PDT could be related to new vessel growth and recanalisation of occluded vessels.
Retinal pigment epithelium disturbances were also observed.
This finding may be related to the original pathology or may indicate that PDT treatment may result in RPE atrophy.
CCK Chan, M Paine, J O’Day (Dept. of Neuro-Ophthalmology, Royal Victorian Eye and Ear Hospital, Melbourne, Australia)
Steroid Management in giant cell arteritis
BJO 2001; 85: 1061-1064
In this retrospective study, the records of 100 consecutive patients with biopsy proved giant cell arteritis (GCA) were reviewed.
Ocular involvement in GCA, is an ophthalmic emergency. If untreated, can progress to permanent loss of vision. Effects of intravenous and oral steroids in GCA were reviewed in 73 patients with visual loss (who were treated).
The management of the patients was studied in the first week after presentation, analyzing (i) types of treatment (ii) dose (iii) effect on visual acuity and (iv) compliations.
All patients (except one) had loss of vision due to anterior ischaemic optic neuropathy (AION).
23% patients had bilateral eye involvement. Vision improved in 29% by a mean of two Snellen chart times after starting steroids.
Improvement of vision was more (40%) in the group who received IV steroids, compared with those who received oral steroids (13%).