Sr MD Devous, RA Thisted, GF Morgan, et al (Univ of Texas, Dallas; Univ of Chicago; Guilford Pharmaceuticals, Baltimore, Md; et al)
SPECT Brain Imaging in Epilepsy: A Meta-analysis
J Nucl Med 39: 285-293, 1998.
Patients failing to respond to medical treatment of partial epileptic seizures originating in the temporal lobe are now treated surgically. Prior to surgery, single photon emission CT (SPECT) is used to assess the patient. Published studies report different sensitivities for SPECT in imaging regional cerebral blood flow on ictal, interictal or postictal scans. This meta analysis (of 624 patients) reviews relevant studies to determine SPECT sensitivities during different stages of seizure.
When SPECT is performed to assist surgery planning for refractory epilepsy, it is important that ictal or postictal images are obtained in conjunction with interictal images. These interictal images are important for comparisons in the evaluation of perfusion changes on the ictal or postictal images.
RJ DeLorenzo, EJ Waterhouse, AR Towne, et al (Virginia Commonwealth Univ, Richmond)
Persistent Nonconvulsive Status Epilepticus After the Control of Convulsive Status Epilepticus.
Epilepsia 39: 833-840, 1998.
Continuous EEG monitoring performed on 164 patients for at least 24 hours after clinical control of CSE, showed that 52% had no after status epilepticus ictal changes.
The authors conclude, that after CSE control, EEG monitoring is essential for recognizing persistent electrographic seizures and nonconvulsive status epilepticus unresponsiveness to routine CSE treatment. Such monitoring after CSE control is also useful in guiding treatment and assessing prognosis.
DM Treiman, for the Veterans Affairs Status Epilepticus Cooperative Study Group (Veterans Affairs Med Ctr, West Los Angeles; Veterans Affairs Med Ctr, Bronx, NY; Veterans Affairs Med Ctr, Birmingham, Ala; et al)
A Comparison of Four Treatments for Generalized Convulsive Status Epilepticus.
N Engl J Med 339 : 792-798, 1998.
Three hundred eight-four patients with a verified diagnosis of status epilepticus and 134 patients with subtle generalized convulsive status epilepticus were enrolled in a 5-year randomized, double-blind, multicentre study.
The four intravenous drugs used were (i) diazepam, 0.15mg/kg body weight followed by phenytoin, 18mg/kg (ii) Lorazepam, 0.1mg/kg (iii) Phenobarbital 15mg/kg and (iv) Phenytoin, 18mg/kg.
The author concludes that Lorazepam is more effective than Phenytoin for the initial IV treatment of overt generalized convulsive status epilepticus. Lorazepam is easier to use than the other agents tested.
FE Dreifuss, NP Rosman, JC Cloyd, et al (Univ of Virginia, Chartlottesville; New England Med Ctr, Boston; Univ of Minnesota, Minneapolis, et al)
A Comparison of Rectal Diazepam Gel and Placebo for Acute Repetitive Seizures.
N Engl J Med 338: 1869-1875, 1998.
Epilepsy affects about 2 million people in the United States. When the patient is actively convulsing, oral and sublingual administration is difficult and hazardous. Rectal diazepam is used to treat acute repetitive, prolonged and febrile seizures. It is effective, well tolerated and can be administered at home by trained caregivers.
P Toti, C De Felice, MLD Plameri, et al (Univ of Siena, Italy; Univ of Antwerp, Wilrijk, Belgium)
Inflammatory Pathogenesis of Cortical Polymicrogyria: An Autopsy Study.
Pediatr Res 44: 291-296, 1998.
This is a study of 32 fetuses spontaneously aborted between 15 and 26 weeks’ gestation because of excessive ascending amnionitis.
Abnormalities in cortical morphology of the brain, can be caused by infection in the fetal adnexa (funisitis – polymorphonuclear leukocytes within the wall of umbilical cord vessels), and the subsequent generation of free radicals.
During hypoxia, the brain generates free radicals. This hypoxia along with free radical generation can cause nonspecific indirect cortical injury that could lead to polymicrogyria in fetuses who survive.
SR Wiener-Vacher, K Mazda (Hopital Robert Debre, Paris)
Asymmetric Otolith Vestibulo-ocular Responses in Children with Idiopathic Scoliosis.
J Pediatr 132: 1028-1032, 1998
About 3% children have idiopathic scoliosis (IS). Disequilibrium of the vestibulospinal pathways controlling the neck and trunk may be involved. Past studies tested this hypothesis based only on semicircular canal function.
In this study of 30 patients with IS, evaluation of otolith function was also included. MR images of the brain, brainstem and medulla were normal. Each individual underwent complete vestibular testing and off-vertical axis rotation to assess otolith vestibular function.
Two thirds of the patients with IS had greater asymmetry in otolith responses than controls. The authors conclude that peripheral dysfunction of otolith receptors seems a likely explanation for IS. They postulate that patients with IS have an imbalance of the central otolith system and this imbalance creates asymmetry in the tonic activity of the spinal muscles during rapid growth such as at puberty.
FG Sheikh, K Pahan, M Khan, et al (Med Univ of South Carolina, Charleston)
Abnormality in Catalase Import Into Peroxisomes Leads to Severe Neurological Disorder.
Proc Natl Acad Sci U S A 95:2961-2966, 1998.
Functional abnormality of peroxisomes leads to progressive neurologic disorders.
Human skin fibroblast cell lines from patients with multiple peroxisomal dysfunctions and normal transport and location of PTS1- and 2-containing proteins (PTS= peroxisomal targeting signal sequence 1 & 2) but with abnormal localization of catalase were studied.
There is a PTS-1 and 2-independent pathway in fibroblasts that is used to transport catalase into human peroxisomes. Impairment of this pathway causes catalase to be improperly localized in the cytosol, instead of being localised in peroxisomes. Without catalase, H2O2 accumulates and suppresses the activities of other peroxisomal proteins, which leads to peroxisomal disease with severe neurologic malfunction.
JM Freeman, EPG Vining, DJ Pillas, et al (Johns Hopkins Med Institutions, Baltimore, Md)
The Efficacy of the Ketogenic Diet – 1998: A Prospective Evaluation of Intervention in 150 children.
Pediatrics 102: 1358-1363, 1998.
The Ketogenic diet (high fat low protein, low CHO diet) first used in the 1920s, is designed for use in children, with difficult-to-control seizures.
The current role of this diet for children with refractory seizures (to modern antiepileptic drugs and surgery) was evaluated in a prospective study of 150 children.
The children were followed for at least one year or until they went off the diet.
The authors conclude that the ketogenic diet appears to reduce seizure frequency for children with refractory seizures.
D Blumer, S Wakhlu, K Davies, et al (Univ of Tennessee, Memphis; Univ of Wisconsin, Madison)
Psychiatric Outcome of Temporal Lobectomy for Epilepsy: Incidence and Treatment of Psychiatric Complications.
Epilepsia 39: 478-486, 1998.
The incidence of psychiatric disorders before and after temporal lobectomy for partial epilepsy, was documented in 55 consecutive patients.
Neuropsychiatric assessments were performed before surgery and during a mean of 2 yrs after surgery.
57% of patients with temporal lobe epilepsy had dysphoric disorders preoperatively. Postoperatively, 39% of this group had either denovo psychiatric complications or exacerbation of preoperative dysphoric disorder. Dysphoric disorders developed postoperatively in 42% of previously unaffected patients, in association with seizure recurrence. Complete absence of seizures postoperatively predicted ultimate excellent psychiatric outcomes.
Psychotropic treatment resolved all postoperative psychiatric complications in patients who complied with the therapy.
Psychiatric morbidity is exceptional in the first months after temporal lobectomy.
M Kimura, H Sejima, H Ozasa et al [ Shimane Med Univ Japan]
Technetium – 99m – HMPAO SPECT in Patients with Hemiconvulsions followed by Todds Paralysis
Pediatr Radiol 28; 92-9, 1998
Single Photon Emission CT [SPECT] is commonly used to image the brain, there are no reports of the SPECT appearance of the brain after postictal transient focal neurologic trauma. This article describes the SPECT appearance in two patients who had prolonged hemiconvulsion with subsequent transient hemiparesis [ Todds paralysis].
SPECT imaging showed that hyperperfusion of the cerebral hemisphere remained many hours after the postictal neurologic deficits resolved, suggesting that the increased cerebral blood flow did not directly impact the hemiparesis.
Prolonged cerebral hyperperfusion was present even though the patients seizure was short.
The findings suggest, that in patients with hemiconvulsions and Todds paralysis, the prolonged cerebral hyperfusion may be the result of impaired vascular autoregulation and its effects on cerebral function.