Speciality
Spotlight

 




 


Ophthalmology


 

 





Neuro-Ophthalmology

     

  • Trobe JP, Sieving PC et al (Univ of Michigan, Ann Arbor)

    The Impact of the Optic Neuritis Treatment Trial on the Practices of Ophthalmologists and Neurologists.

    Ophthalmology 106: 2047-2053, 1999

        

    A large randomized clinical trial – the ONTT (optic neuritis treatment trial) of the effects of prednisone and IV methylprednisolone was carried out in patients with optic neuritis.

       

    This trial has prompted quite a change in the approach to the treatment of optic neuritis. Both ophthalmologists and neurologists have abandoned the use of oral prednisolone ALONE. They prefer an initial treatment with IV methylprednisolone followed later by oral
    prednisolone.

       

  • 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.

        

  • Brady KM, Brar AS, Lee AG, et al (Baylor College of Medicine, Houston; Univ of Texas, Houston)

    Optic Neuritis in Children : Clinical Features and Visual Outcome.

    J AAPOS 3: 98-103, 1999

       

    The authors analyzed the clinical characteristics of paediatric optic neuritis, of 39 affected eyes.

       

    Though there is profound visual loss at the onset of neuritis, most of the eyes had good visual recovery. However, about ¼ patients, did not achieve visual acuity of 20/40 or better. 

       

    Visual recovery was more likely in patients with normal MRI findings, and in those who were less than 6 years old. Two patients, who had contiguous sinusitis, had poor visual recovery.

       

  • Rogers AH, Rogers GL, et al (Boston Univ.; Children’s Hosp., Columbus, Ohio)

    Pseudotumor Cerebri in Children Receiving Recombinant Human Growth Hormone.

    Ophthalmology 106: 1186-1190, 1999

       

    Growth hormone (GH) is used for children with idiopathic GH deficiency, chronic renal insufficiency, Turner’s syndrome and delayed puberty.

       

    This report (of 3 children) links the therapeutic use of recombinant human GH (rhGH) with pseudotumor cerebri. When papilledema was found, the patients underwent lumbar puncture and imaging studies to exclude other causes. Administration of rhGH was discontinued.

       

    The symptoms produced included headache, deterioration of visual acuity and papilloedema.

       

    These patients should have MRI and angiography to exclude any occult CNS mass lesion and sagittal sinus thrombosis. Lumbar puncture also should be done to exclude inflammatory meningitis.

       

  • DC Macaluso WT Shults, FT Fraunfelder [Oregon Health Sciences Univ, Portland]

    Features of Amiodarone-Induced Optic Neuropathy

    Am J Ophthalmol 127: 610-612, 1999

      

    Optic Neuropathy is a side effect of the cardiac anti-arrhythmic drug amiodarone. 

      

    Distinguishing between amiodarone-induced optic neuropathy and optic neuropathy due to nonarteritic anterior ischemia [NAION] can be difficult. 

      

    The authors reviewed 73 patients with amiodarone induced optic neuropathy and compared the clinical features with those of NAION.

      

    Visual loss in amiodarone-induced neuropathy is insidious [months] with slow progress and deficit usually stabilize after the drug’s discontinuation. 

      

    In NAION, the loss is acute [ days to weeks] and is complete at its onset.

        

    Visual loss is bilateral in the former but unilateral in the latter.

        

    Resolution of disc oedema, peripapillary nerve fiber layer hemorrhages takes months following amiodarone, whereas in NAION resolution occurs sooner [within weeks].

      

    Patients should undergo an opthalmologic examination, before starting amiodarone therapy and every six months thereafter. If optic neuropathy develops, and a therapeutic alternative could be used, amiodarone should be withheld.

       

  • RD
    Learish, O Brustle, S-C Zhang, et al [ Univ of Wisconsin, Madison; Univ of Bonn,
    Germany ]

    Intraventricular Transplantation of Oligodendrocyte Progenitors into a Fetal Myelin Mutant Results in Widespread Formation of Myelin

    Ann Neurol 46: 716-722, 1999

       

    The aim of this study is to propose that myelin disorders such as multiple sclerosis may benefit from the technique of transplanting myelin forming cells into the ventricular system.

      

    Glial cell progenitors were transplanted into the cerebral ventricles of embryonic myelin-deficient rats.

      

    Migrated cells were noted both in white and gray matter . Myelin production was stimulated at diverse sites viz corpus callosum, the optic nerve, and the cerebellum.

      

    Differentiation of progenitors into oligodendrocytes allows myelin production. Hence, repair of myelin in disorders like multiple sclerosis may be possible.

         

  • DS
    Mojon, J Mathis, M Zulauf, et al (Univ of Bern, Switzerland; Univ of Basel, Switzerland)

    Optic Neuropathy Associated with Sleep Apnea Syndrome.

    Ophthalmology 105:874-877, 1998.

       

    Sleep apnea syndrome (SAS) is typified by recurrent complete or partial upper airway obstruction during sleep. Floppy eyelid syndrome and keratoconus may be associated ocular findings.

       

    Patients with SAS had visual field defects consistent with an optic neuropathy. Visual field defects remained stable over 18 months in 2 of 3 patients with severe SAS who were treated with continuous positive airway pressure (CPAP).

       

    Field deterioration may be prevented by CPAP therapy.

       

  • Dm Jacobson (Marshfield Clinic,
    Wis) 

    Pupil Involvement in Patients with Diabetes-associated Oculomotor Nerve Palsy. 

    Arch Ophthalmol 116:723-727, 1998.

         

    The size and reactivity of the pupil is an accurate indication of oculomotor function. The frequency of pupil involvement in patients with diabetes associated third nerve palsy was estimated. Oculomotor nerve palsy occurs more frequently than previously suspected in patients with diabetes.

         

  • CA
    Girkin, JD Perry, NR Miller (Johns Hopkins Hosp, Baltimore, Md) 

    A Relative Afferent Pupillary Defect Without Any Visual Sensory Deficit. 

    Arch Ophthalmol 116:1544-1545, 1998.

       


    This is an interesting case report about an afferent pupillary defect in a
    patient where no afferent visual deficit could be demonstrated.

       

    Before reaching the lateral geniculate body, both afferent axons and visual axons provide information to the pretectal nuclei. The afferent fibers reach the pretectal area via the brachium of the superior colliculus. Unilateral lesions of this brachium can cause a contralateral relative afferent pupillary defect, even though the affected eye has normal visual acuity, color vision and visual fields. 

        

  • H-C
    Koennecke, S Seyfert (Freie Universitat Berlin).

    Mydriatic Pupil as the Presenting Sign of Common Carotid Artery Dissection. 

    Stroke 29:2653-2655, 1998.

        

    Dissection of the internal carotid artery is sometimes associated with ipsilateral oculomotor nerve dysfunction. 

       

    The case report is of a patient in whom pupillary dysfunction from evolving paresis of the third nerve was the FIRST clinical sign of acute dissection of the common carotid artery (CCA) and impending cereberal ischaemia.

        

    In this case the mydriatic pupil was an unusual sign of compromised carotid blood flow (miosis is commoner in carotid dissection).

    Carotid endartectomy successfully reversed the third nerve palsy and cerebral ischemia.

        

  • CF
    Parsa, PE Grant, Jr WP Dillon, et al (Univ of California, San Francisco; Salk Inst, San Francisco). 

    Absence of the Abducens Nerve in Duane Syndrome Verified by Magnetic Resonance Imaging. 

    Am J Ophthalmol 125: 399-401, 1998.

       

    Every autopsy of patients with Duane’s syndrome shows anomalous innervation of the lateral rectus muscle on the affected side by the ipsilateral 3rd nerve and also absence of the 6th nerve.

        

    The authors report the latter finding in vivo. The absence of the abducens nerve on the affected side can be shown by high resolution, 3-dimensional spoiled gradient recalled acquisition magnetic resonance imaging and high matrix thin section volumetric images.

        

  • VA
    Purvin, Aki Kawasaki, et al (Midwest Eye Institute, Indianapolis)

    Papilledema and Obstructive Sleep Apnea Syndrome

    Arch Ophthalmol.Vol.118, Dec.2000, pg.1626-1630.

       

    Four patients with sleep apnea syndrome (SAS) and papilledema (PE) underwent complete neuro-ophthalmologic evaluation and lumbar puncture. In one patient, continuous 24-hour intracranial pressure (ICP) monitoring was also performed.

       

    The authors propose that PE in SAS is due to episodic nocturnal hypoxemia and hypercarbia which result in increased ICP secondary to cerebral vasodilatation. The intermittent ICP elevation is sufficient to cause persistent PE.

        

    The patients may be asymptomatic initially, but may later present with visual loss secondary to PE.

        

  • DM Jacobson (Marshfield Clinic, Wis)

    Symptomatic Compression of the Optic Nerve by the Carotid Artery; Clinical Profile of 18 patients with 24 affects eyes identified by Magnetic Resonance Imaging.

    Ophthalmology 106: 1994-2004, 1999

        

    This is a retrospective, observation case study (of 18 patients) with compression of the intracranial optic nerve by the supraclinoid internal carotid artery. These cases were evaluated between 1988 and 1998 (ten years).

       

    MRI is the diagnostic modality of choice. Intracranial compression of the optic nerve should be considered when a patient has a typical or unexplained progressive visual loss.

        

    Most patients were found to have nerve fiber bundle injury and excavation of the optic disc.

       

  • C F Parsa, CS Hoyt, et al (The Johns Hopkins Hosp, Baltimore)

    Spontaneous Regression of Optic Gliomas

    Arch.Ophthalmol, April 2001; vol.119. p.516-529

      

    This article, documents in detail, 13 patients of optic nerve glioma.

       

    Spontaneous tumor shrinkage was noted in 12 patients. Tumor regression was associated with improvement in vision in 10 of 13 patients, stability of function in one, and deterioration in two.

       

    This possibility of spontaneous regression of an optic glioma should be considered in the planning of treatment of patients with these tumors.  

           

  • Jacobs LD, and the CHAMPS Study Group (State Univ. New York, Buffalo; et al)

    Intramuscular Interferon Beta-1a Therapy Initiated During a First Demyelinating Event in Multiple Sclerosis.

    N Engl J Med 343: 898-904, 2000

           

    Interferon-b is used to treat patients with established multiple sclerosis (MS). Whether treatment at the beginning of the course of the disease would benefit patients is not known.

          

    This clinical trial was conducted to determine whether interferon-b treatment of patients with a first demyelinating event and MRI evidence of prior demyelination, reduced the incidence of clinically definite MS.

           

    The results demonstrated that the above treatment did benefit patients with subclinical demyelinating lesions of the brain (as revealed by MRI).

          

    MRI brain scans are justified at the time of a first clinical demyelinating event, in order to search for further evidence of MS. 

          

    Preventing or delaying further demyelination events and reducing disease progression probably will have long-term benefits.

         

  • Kerman
    WN, Viscoli CM, et al (Yale Univ. New Haven, Conn: Univ of Cincinnati, Ohio; Mayo Clinic, Jacksonville, Fla; et al)

    Phenylpropanolamine and the Risk of Hemorrhagic Stroke

    N Engl J Med 343: 1826-1832, 2000.

           

    702 patients, aged 18 to 49 yrs were analysed. Patients had a subarachnoid or intracerebral haemorrhage within 30 days before enrollment and no previous diagnosis of brain lesions.

          

    The authors conclude that phenylpropanolamine, a synthetic sympathomimetic in appetite suppressants and possibly in cough and cold mediations, appears to be an independent risk factor for haemorrhageic stroke in women.

          

    The Food and Drug Administration is considering banning this substance.

           

  • Evangelou N, Esiri MM, Smith S, et al (Univ.of Oxford, England)

    Quantitative Pathological Evidence for Axonal Loss in Normal Appearing White Matter in Multiple Sclerosis.

    Ann Neurol 47: 391-395, 2000

          

    The degree of axonal involvement in normal appearing white matter (NAWM) in patients with multiple sclerosis (MS) should be accurately defined.

          

    Disability is inversely associated with N-acetylaspartate levels in NAWM.

          

    In a study involving pathologic examination of NAWM atrophy and axonal density loss in the corpus callosum of 8 patients with MS, it was found that these patients had a significantly reduced axonal density.

         

    Substantial volumes of axonal loss do occur in MS, possibly due to a secondary attack upon axons by inflammatory mediators, macrophages, polymorphonuclear leukocytes and lymphocytes.

          

    Therefore, primary demyelination should be treated aggressively to limit the degree of white matter inflammation and secondary axonal loss.

         

  • Purvin VA, Kawasaki A, Yee RD (Indiana Univ, Indianapolis)

    Papilledema and Obstructive Sleep Apnea Syndrome

    Arch Ophthalmol 118: 1626-1630, 2000

           

    The authors report a case of Sleep Apnea Syndrome (SAS) in a morbidly obese 20 yr.old man who had marked visual loss in his left eye.

          

    There was a dense central scotoma and generalized depression of the field. Fundi showed bilateral disc oedema and peripapillary hemorrhages.

          

    During sleep there were repeated apneic spells caused by upper airway obstruction. These spells were associated with decreased oxygen saturation and increased intracranial pressure (ICP).

          

    Patient was treated with acetazolamide and tracheostomy was performed. Optic nerve function, vision and disc edema improved within 5 days.

          

    The authors postulate that this diagnosis should be considered in patients who are obese with possible airway obstruction, and have unexplained disc oedema.

          

  • Kotani N, Kushikata T, Hashimoto H, et al (Univ of Hirosaki, Japan)

    Intrathecal Methylprednisolone for Intractable Postherpetic Neuralgia

    N Engl J Med 343: 1514-1519, 2000.

          

    Postherpetic neuralgia is believed to have an inflammatory component.

          

    The authors investigated the efficacy of intrathecally administered methyl prednisolone for reducing pain. Two hundred and seventy patients were analyzed (follow-up 2 yrs). 

         

    They were divided into 3 groups (1) intrathecal methyl prednisolone plus lidocaine (2) lidocaine alone (3) No therapy. Periodic pain assessment and CSF examination before and at the end of treatment for estimation of interleukin –8 (IL-8) were carried out.

         

    The first group had maximum pain relief and IL-8 levels declined by 50%.

          

    Intrathecal methylprednisolone produced no adverse effect.

          

  • Morales J, Brown SM, Abdul-Rahim AS, et al (Texas Tech Univ, Lubbock)

    Ocular Effects of Apraclonidine in Horner Syndrome

    Arch Ophthalmol 118: 951-954, 2000.

          

    Apraclonidine, an alpha-adrenergic receptor agonist, decreases aqueous production and intraocular pressure (IOP). The location of action of apraclonidine for reducing aqueous production was found to be postjunctional a2 receptors in the ciliary body. 

          

    Eyes with Horners syndrome, in which 1% apraclonidine was instilled, demonstrated papillary dilatation compared with normal eyes.

         

    The upregulation of a-receptors that occurs with Horner’s syndrome, unmasks apraclonidine’s a-1 effect which causes papillary dilatation.

         

  • Movaghar M, Slavin ML (Albert Einstein College of Medicine, Great Neck, NY)

    Effect of Local Heat Versus Ice on Blepharoptosis Resulting From Ocular Myasthenia.

    Ophthalmology 107: 2209-2214, 2000

         

    The effect of local heat versus cold on ptosis was investigated in 4 patients with myasthenia.

         

    Four patients with unilateral ptosis were given heat test, ice test, modified sleep test or a combination of these tests.

          

    The authors found that ptosis improved dramatically in all patients who rested their eyes, regardless of heat or cold treatment.

           

  • Dickersin K, for the Ischemic Optic Neuropathy Decompression Trial Research Group (Allegheny Gen Hosp, Pittsburgh, Pa; et al )

    Ischemic Optic Neuropathy Decompression Trial : Twenty-Four-Month Update.

    Arch Ophthalmol 118: 793-798, 2000

      

    Nonarteritic anterior ischemic optic neuropathy (NAION) is the commonest cause of acute optic neuropathy.

     

    258 patients, 50 yrs and above, with NAION and visual acuity of 20/64 or worse but better than no light perception, were randomly assigned to optic nerve decompression surgery (ONDS) or careful follow-up.

     

    Patients were examined at 3, 6, 12, 18 and 24 months. The authors conclude that ONDS appears to have NO benefit over careful follow up in patients with
    NAION.

        

  • Unsold AS, Rizzo JF III, Lessell S (Harvard Med School, Boston;Massachusetts Eye and Ear Infirmary, Boston).

    Optic Neuropathy After Burns

    Arch Ophthalmol 118: 1696-1698, 2000

      

    This is a case report describing a patient with postburn optic neuropathy, who did not fully recover vision. 10 additional cases were identified in literature.

     

    Patients with severe burns of the skin may develop bilateral optic neuropathy. Some may recover spontaneously. Retinal hemorrhage and edema are common.

     

    Visual loss immediate or later may not be accompanied by neurologic signs. Pathogenesis of postburn optic neuropathy has not been established.

       

  • P.
    Cackett, C. R. Weir, et al (Gartnavel Gen Hosp, Glasgow, UK)

    Interesting Case Report- Asymptomatic Oculopalatal Myoclonus: An Unusual Case

    BJO, Jan.2002, 86(1): 116

      

    This unusual case was a 61 year old man – admitted to the neurosurgery department following head trauma. CT scan showed subarachnoid bleeding. An MRI showed left frontal and posterior parietal contusions and a small brain stem
    haemorrhage.

      

    Following head injury he complained of diplopia on downgaze. Examination revealed bilateral 4th nerve palsy which resolved spontaneously. Nine months later the patient developed acute glaucoma in the right eye for, which he underwent
    trabeculectomy.

      

    While attending 8 years after head injury, an audible click was heard emanating from the patient. Examination of the soft palate showed rhythmic contractions, synchronized with the auditory clicking. There was a right unilateral vertical pendular nystagmus (no nystagmus left eye).

      

    A diagnosis of oculopalatal myoclonus was made (secondary to brain stem haemorrhage). However the patient was
    asymptomatic.

        

  • Banta JT, Farris BK (Oklahoma Univ, Oklahoma City)

    Pseudotumor Cerebri and Optic Nerve Sheath Decompression

    Ophthalmology 107: 1907-1912, 2000

      

    Pseudotumor cerebri (PTC) can lead to mild to severe vision loss as a consequence of raised intracranial pressure. Optic nerve sheath decompression (ONSD) has been reported to be a safe and effective method of halting progressive vision loss. PTC is 5 times commoner in women. Between 1988 and 1998, 158 eyes in patients with PTC underwent ONSD. All patients had papilledema. Visual acuity was stable or improved in 94% eyes and worsened in 6% eyes.

      

    Visual fields were stable or improved in 88% and worsened in 12%. Complications included diplopia (30 patients), dellen (6 patients), anisocoria (6 patients), orbital apex syndrome (one patient) and traumatic optic neuropathy (one patient).

      

    One patient had a poor vision resulting from pressured traumatic optic neuropathy. New vision loss occurred upto 5 years after
    ONSD.

      

    The authors conclude that ONSD is safe and effective for patients with PTC and improved visual acuity and visual fields in most patients.

        

 



 

 

Speciality Spotlight

 

 

Neuro-Ophthalmology
     

  • Trobe JP, Sieving PC et al (Univ of Michigan, Ann Arbor)
    The Impact of the Optic Neuritis Treatment Trial on the Practices of Ophthalmologists and Neurologists.
    Ophthalmology 106: 2047-2053, 1999
        
    A large randomized clinical trial – the ONTT (optic neuritis treatment trial) of the effects of prednisone and IV methylprednisolone was carried out in patients with optic neuritis.
       
    This trial has prompted quite a change in the approach to the treatment of optic neuritis. Both ophthalmologists and neurologists have abandoned the use of oral prednisolone ALONE. They prefer an initial treatment with IV methylprednisolone followed later by oral prednisolone.
       

  • 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.
        

  • Brady KM, Brar AS, Lee AG, et al (Baylor College of Medicine, Houston; Univ of Texas, Houston)
    Optic Neuritis in Children : Clinical Features and Visual Outcome.
    J AAPOS 3: 98-103, 1999
       
    The authors analyzed the clinical characteristics of paediatric optic neuritis, of 39 affected eyes.
       
    Though there is profound visual loss at the onset of neuritis, most of the eyes had good visual recovery. However, about ¼ patients, did not achieve visual acuity of 20/40 or better. 
       
    Visual recovery was more likely in patients with normal MRI findings, and in those who were less than 6 years old. Two patients, who had contiguous sinusitis, had poor visual recovery.
       

  • Rogers AH, Rogers GL, et al (Boston Univ.; Children’s Hosp., Columbus, Ohio)
    Pseudotumor Cerebri in Children Receiving Recombinant Human Growth Hormone.
    Ophthalmology 106: 1186-1190, 1999
       
    Growth hormone (GH) is used for children with idiopathic GH deficiency, chronic renal insufficiency, Turner’s syndrome and delayed puberty.
       
    This report (of 3 children) links the therapeutic use of recombinant human GH (rhGH) with pseudotumor cerebri. When papilledema was found, the patients underwent lumbar puncture and imaging studies to exclude other causes. Administration of rhGH was discontinued.
       
    The symptoms produced included headache, deterioration of visual acuity and papilloedema.
       
    These patients should have MRI and angiography to exclude any occult CNS mass lesion and sagittal sinus thrombosis. Lumbar puncture also should be done to exclude inflammatory meningitis.
       

  • DC Macaluso WT Shults, FT Fraunfelder [Oregon Health Sciences Univ, Portland]
    Features of Amiodarone-Induced Optic Neuropathy
    Am J Ophthalmol 127: 610-612, 1999
      
    Optic Neuropathy is a side effect of the cardiac anti-arrhythmic drug amiodarone. 
      
    Distinguishing between amiodarone-induced optic neuropathy and optic neuropathy due to nonarteritic anterior ischemia [NAION] can be difficult. 
      
    The authors reviewed 73 patients with amiodarone induced optic neuropathy and compared the clinical features with those of NAION.
      
    Visual loss in amiodarone-induced neuropathy is insidious [months] with slow progress and deficit usually stabilize after the drug’s discontinuation. 
      
    In NAION, the loss is acute [ days to weeks] and is complete at its onset.
        
    Visual loss is bilateral in the former but unilateral in the latter.
        
    Resolution of disc oedema, peripapillary nerve fiber layer hemorrhages takes months following amiodarone, whereas in NAION resolution occurs sooner [within weeks].
      
    Patients should undergo an opthalmologic examination, before starting amiodarone therapy and every six months thereafter. If optic neuropathy develops, and a therapeutic alternative could be used, amiodarone should be withheld.
       

  • RD Learish, O Brustle, S-C Zhang, et al [ Univ of Wisconsin, Madison; Univ of Bonn, Germany ]
    Intraventricular Transplantation of Oligodendrocyte Progenitors into a Fetal Myelin Mutant Results in Widespread Formation of Myelin
    Ann Neurol 46: 716-722, 1999
       
    The aim of this study is to propose that myelin disorders such as multiple sclerosis may benefit from the technique of transplanting myelin forming cells into the ventricular system.
      
    Glial cell progenitors were transplanted into the cerebral ventricles of embryonic myelin-deficient rats.
      
    Migrated cells were noted both in white and gray matter . Myelin production was stimulated at diverse sites viz corpus callosum, the optic nerve, and the cerebellum.
      
    Differentiation of progenitors into oligodendrocytes allows myelin production. Hence, repair of myelin in disorders like multiple sclerosis may be possible.
         

  • DS Mojon, J Mathis, M Zulauf, et al (Univ of Bern, Switzerland; Univ of Basel, Switzerland)
    Optic Neuropathy Associated with Sleep Apnea Syndrome.
    Ophthalmology 105:874-877, 1998.
       
    Sleep apnea syndrome (SAS) is typified by recurrent complete or partial upper airway obstruction during sleep. Floppy eyelid syndrome and keratoconus may be associated ocular findings.
       
    Patients with SAS had visual field defects consistent with an optic neuropathy. Visual field defects remained stable over 18 months in 2 of 3 patients with severe SAS who were treated with continuous positive airway pressure (CPAP).
       
    Field deterioration may be prevented by CPAP therapy.
       

  • Dm Jacobson (Marshfield Clinic, Wis) 
    Pupil Involvement in Patients with Diabetes-associated Oculomotor Nerve Palsy. 
    Arch Ophthalmol 116:723-727, 1998.
         
    The size and reactivity of the pupil is an accurate indication of oculomotor function. The frequency of pupil involvement in patients with diabetes associated third nerve palsy was estimated. Oculomotor nerve palsy occurs more frequently than previously suspected in patients with diabetes.
         

  • CA Girkin, JD Perry, NR Miller (Johns Hopkins Hosp, Baltimore, Md) 
    A Relative Afferent Pupillary Defect Without Any Visual Sensory Deficit. 
    Arch Ophthalmol 116:1544-1545, 1998.
       

    This is an interesting case report about an afferent pupillary defect in a patient where no afferent visual deficit could be demonstrated.
       
    Before reaching the lateral geniculate body, both afferent axons and visual axons provide information to the pretectal nuclei. The afferent fibers reach the pretectal area via the brachium of the superior colliculus. Unilateral lesions of this brachium can cause a contralateral relative afferent pupillary defect, even though the affected eye has normal visual acuity, color vision and visual fields. 
        

  • H-C Koennecke, S Seyfert (Freie Universitat Berlin).
    Mydriatic Pupil as the Presenting Sign of Common Carotid Artery Dissection. 
    Stroke 29:2653-2655, 1998.
        
    Dissection of the internal carotid artery is sometimes associated with ipsilateral oculomotor nerve dysfunction. 
       
    The case report is of a patient in whom pupillary dysfunction from evolving paresis of the third nerve was the FIRST clinical sign of acute dissection of the common carotid artery (CCA) and impending cereberal ischaemia.
        
    In this case the mydriatic pupil was an unusual sign of compromised carotid blood flow (miosis is commoner in carotid dissection).
    Carotid endartectomy successfully reversed the third nerve palsy and cerebral ischemia.
        

  • CF Parsa, PE Grant, Jr WP Dillon, et al (Univ of California, San Francisco; Salk Inst, San Francisco). 
    Absence of the Abducens Nerve in Duane Syndrome Verified by Magnetic Resonance Imaging. 
    Am J Ophthalmol 125: 399-401, 1998.
       
    Every autopsy of patients with Duane’s syndrome shows anomalous innervation of the lateral rectus muscle on the affected side by the ipsilateral 3rd nerve and also absence of the 6th nerve.
        
    The authors report the latter finding in vivo. The absence of the abducens nerve on the affected side can be shown by high resolution, 3-dimensional spoiled gradient recalled acquisition magnetic resonance imaging and high matrix thin section volumetric images.
        

  • VA Purvin, Aki Kawasaki, et al (Midwest Eye Institute, Indianapolis)
    Papilledema and Obstructive Sleep Apnea Syndrome
    Arch Ophthalmol.Vol.118, Dec.2000, pg.1626-1630.
       
    Four patients with sleep apnea syndrome (SAS) and papilledema (PE) underwent complete neuro-ophthalmologic evaluation and lumbar puncture. In one patient, continuous 24-hour intracranial pressure (ICP) monitoring was also performed.
       
    The authors propose that PE in SAS is due to episodic nocturnal hypoxemia and hypercarbia which result in increased ICP secondary to cerebral vasodilatation. The intermittent ICP elevation is sufficient to cause persistent PE.
        
    The patients may be asymptomatic initially, but may later present with visual loss secondary to PE.
        

  • DM Jacobson (Marshfield Clinic, Wis)
    Symptomatic Compression of the Optic Nerve by the Carotid Artery; Clinical Profile of 18 patients with 24 affects eyes identified by Magnetic Resonance Imaging.
    Ophthalmology 106: 1994-2004, 1999
        
    This is a retrospective, observation case study (of 18 patients) with compression of the intracranial optic nerve by the supraclinoid internal carotid artery. These cases were evaluated between 1988 and 1998 (ten years).
       
    MRI is the diagnostic modality of choice. Intracranial compression of the optic nerve should be considered when a patient has a typical or unexplained progressive visual loss.
        
    Most patients were found to have nerve fiber bundle injury and excavation of the optic disc.
       

  • C F Parsa, CS Hoyt, et al (The Johns Hopkins Hosp, Baltimore)
    Spontaneous Regression of Optic Gliomas
    Arch.Ophthalmol, April 2001; vol.119. p.516-529
      
    This article, documents in detail, 13 patients of optic nerve glioma.
       
    Spontaneous tumor shrinkage was noted in 12 patients. Tumor regression was associated with improvement in vision in 10 of 13 patients, stability of function in one, and deterioration in two.
       
    This possibility of spontaneous regression of an optic glioma should be considered in the planning of treatment of patients with these tumors.  
           

  • Jacobs LD, and the CHAMPS Study Group (State Univ. New York, Buffalo; et al)
    Intramuscular Interferon Beta-1a Therapy Initiated During a First Demyelinating Event in Multiple Sclerosis.
    N Engl J Med 343: 898-904, 2000
           
    Interferon-b is used to treat patients with established multiple sclerosis (MS). Whether treatment at the beginning of the course of the disease would benefit patients is not known.
          
    This clinical trial was conducted to determine whether interferon-b treatment of patients with a first demyelinating event and MRI evidence of prior demyelination, reduced the incidence of clinically definite MS.
           
    The results demonstrated that the above treatment did benefit patients with subclinical demyelinating lesions of the brain (as revealed by MRI).
          
    MRI brain scans are justified at the time of a first clinical demyelinating event, in order to search for further evidence of MS. 
          
    Preventing or delaying further demyelination events and reducing disease progression probably will have long-term benefits.
         

  • Kerman WN, Viscoli CM, et al (Yale Univ. New Haven, Conn: Univ of Cincinnati, Ohio; Mayo Clinic, Jacksonville, Fla; et al)
    Phenylpropanolamine and the Risk of Hemorrhagic Stroke
    N Engl J Med 343: 1826-1832, 2000.
           
    702 patients, aged 18 to 49 yrs were analysed. Patients had a subarachnoid or intracerebral haemorrhage within 30 days before enrollment and no previous diagnosis of brain lesions.
          
    The authors conclude that phenylpropanolamine, a synthetic sympathomimetic in appetite suppressants and possibly in cough and cold mediations, appears to be an independent risk factor for haemorrhageic stroke in women.
          
    The Food and Drug Administration is considering banning this substance.
           

  • Evangelou N, Esiri MM, Smith S, et al (Univ.of Oxford, England)
    Quantitative Pathological Evidence for Axonal Loss in Normal Appearing White Matter in Multiple Sclerosis.
    Ann Neurol 47: 391-395, 2000
          
    The degree of axonal involvement in normal appearing white matter (NAWM) in patients with multiple sclerosis (MS) should be accurately defined.
          
    Disability is inversely associated with N-acetylaspartate levels in NAWM.
          
    In a study involving pathologic examination of NAWM atrophy and axonal density loss in the corpus callosum of 8 patients with MS, it was found that these patients had a significantly reduced axonal density.
         
    Substantial volumes of axonal loss do occur in MS, possibly due to a secondary attack upon axons by inflammatory mediators, macrophages, polymorphonuclear leukocytes and lymphocytes.
          
    Therefore, primary demyelination should be treated aggressively to limit the degree of white matter inflammation and secondary axonal loss.
         

  • Purvin VA, Kawasaki A, Yee RD (Indiana Univ, Indianapolis)
    Papilledema and Obstructive Sleep Apnea Syndrome
    Arch Ophthalmol 118: 1626-1630, 2000
           
    The authors report a case of Sleep Apnea Syndrome (SAS) in a morbidly obese 20 yr.old man who had marked visual loss in his left eye.
          
    There was a dense central scotoma and generalized depression of the field. Fundi showed bilateral disc oedema and peripapillary hemorrhages.
          
    During sleep there were repeated apneic spells caused by upper airway obstruction. These spells were associated with decreased oxygen saturation and increased intracranial pressure (ICP).
          
    Patient was treated with acetazolamide and tracheostomy was performed. Optic nerve function, vision and disc edema improved within 5 days.
          
    The authors postulate that this diagnosis should be considered in patients who are obese with possible airway obstruction, and have unexplained disc oedema.
          

  • Kotani N, Kushikata T, Hashimoto H, et al (Univ of Hirosaki, Japan)
    Intrathecal Methylprednisolone for Intractable Postherpetic Neuralgia
    N Engl J Med 343: 1514-1519, 2000.
          
    Postherpetic neuralgia is believed to have an inflammatory component.
          
    The authors investigated the efficacy of intrathecally administered methyl prednisolone for reducing pain. Two hundred and seventy patients were analyzed (follow-up 2 yrs). 
         
    They were divided into 3 groups (1) intrathecal methyl prednisolone plus lidocaine (2) lidocaine alone (3) No therapy. Periodic pain assessment and CSF examination before and at the end of treatment for estimation of interleukin –8 (IL-8) were carried out.
         
    The first group had maximum pain relief and IL-8 levels declined by 50%.
          
    Intrathecal methylprednisolone produced no adverse effect.
          

  • Morales J, Brown SM, Abdul-Rahim AS, et al (Texas Tech Univ, Lubbock)
    Ocular Effects of Apraclonidine in Horner Syndrome
    Arch Ophthalmol 118: 951-954, 2000.
          
    Apraclonidine, an alpha-adrenergic receptor agonist, decreases aqueous production and intraocular pressure (IOP). The location of action of apraclonidine for reducing aqueous production was found to be postjunctional a2 receptors in the ciliary body. 
          
    Eyes with Horners syndrome, in which 1% apraclonidine was instilled, demonstrated papillary dilatation compared with normal eyes.
         
    The upregulation of a-receptors that occurs with Horner’s syndrome, unmasks apraclonidine’s a-1 effect which causes papillary dilatation.
         

  • Movaghar M, Slavin ML (Albert Einstein College of Medicine, Great Neck, NY)
    Effect of Local Heat Versus Ice on Blepharoptosis Resulting From Ocular Myasthenia.
    Ophthalmology 107: 2209-2214, 2000
         
    The effect of local heat versus cold on ptosis was investigated in 4 patients with myasthenia.
         
    Four patients with unilateral ptosis were given heat test, ice test, modified sleep test or a combination of these tests.
          
    The authors found that ptosis improved dramatically in all patients who rested their eyes, regardless of heat or cold treatment.
           

  • Dickersin K, for the Ischemic Optic Neuropathy Decompression Trial Research Group (Allegheny Gen Hosp, Pittsburgh, Pa; et al )
    Ischemic Optic Neuropathy Decompression Trial : Twenty-Four-Month Update.
    Arch Ophthalmol 118: 793-798, 2000
      
    Nonarteritic anterior ischemic optic neuropathy (NAION) is the commonest cause of acute optic neuropathy.
     
    258 patients, 50 yrs and above, with NAION and visual acuity of 20/64 or worse but better than no light perception, were randomly assigned to optic nerve decompression surgery (ONDS) or careful follow-up.
     
    Patients were examined at 3, 6, 12, 18 and 24 months. The authors conclude that ONDS appears to have NO benefit over careful follow up in patients with NAION.
        

  • Unsold AS, Rizzo JF III, Lessell S (Harvard Med School, Boston;Massachusetts Eye and Ear Infirmary, Boston).
    Optic Neuropathy After Burns
    Arch Ophthalmol 118: 1696-1698, 2000
      
    This is a case report describing a patient with postburn optic neuropathy, who did not fully recover vision. 10 additional cases were identified in literature.
     
    Patients with severe burns of the skin may develop bilateral optic neuropathy. Some may recover spontaneously. Retinal hemorrhage and edema are common.
     
    Visual loss immediate or later may not be accompanied by neurologic signs. Pathogenesis of postburn optic neuropathy has not been established.
       

  • P. Cackett, C. R. Weir, et al (Gartnavel Gen Hosp, Glasgow, UK)
    Interesting Case Report- Asymptomatic Oculopalatal Myoclonus: An Unusual Case
    BJO, Jan.2002, 86(1): 116
      
    This unusual case was a 61 year old man – admitted to the neurosurgery department following head trauma. CT scan showed subarachnoid bleeding. An MRI showed left frontal and posterior parietal contusions and a small brain stem haemorrhage.
      
    Following head injury he complained of diplopia on downgaze. Examination revealed bilateral 4th nerve palsy which resolved spontaneously. Nine months later the patient developed acute glaucoma in the right eye for, which he underwent trabeculectomy.
      
    While attending 8 years after head injury, an audible click was heard emanating from the patient. Examination of the soft palate showed rhythmic contractions, synchronized with the auditory clicking. There was a right unilateral vertical pendular nystagmus (no nystagmus left eye).
      
    A diagnosis of oculopalatal myoclonus was made (secondary to brain stem haemorrhage). However the patient was asymptomatic.
        

  • Banta JT, Farris BK (Oklahoma Univ, Oklahoma City)
    Pseudotumor Cerebri and Optic Nerve Sheath Decompression
    Ophthalmology 107: 1907-1912, 2000
      
    Pseudotumor cerebri (PTC) can lead to mild to severe vision loss as a consequence of raised intracranial pressure. Optic nerve sheath decompression (ONSD) has been reported to be a safe and effective method of halting progressive vision loss. PTC is 5 times commoner in women. Between 1988 and 1998, 158 eyes in patients with PTC underwent ONSD. All patients had papilledema. Visual acuity was stable or improved in 94% eyes and worsened in 6% eyes.
      
    Visual fields were stable or improved in 88% and worsened in 12%. Complications included diplopia (30 patients), dellen (6 patients), anisocoria (6 patients), orbital apex syndrome (one patient) and traumatic optic neuropathy (one patient).
      
    One patient had a poor vision resulting from pressured traumatic optic neuropathy. New vision loss occurred upto 5 years after ONSD.
      
    The authors conclude that ONSD is safe and effective for patients with PTC and improved visual acuity and visual fields in most patients.
        

 

 

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