Biomedical subjects

E L So

Publications and source records attributed to E L So.

64 records · Page 4Linked to original sources

PubMed1993

Alfentanil-induced epileptiform activity in patients with partial epilepsy.

We performed a retrospective study investigating the effect of alfentanil hydrochloride on electrocorticography (ECoG) in 23 patients with intractable nonlesional partial epilepsy undergoing anterior temporal lobectomies at this institution. Alfentanil is a short-acting, parenteral, opioid analgesic with a rapid onset of action. Opioid drugs have the potential to induce hippocampal electrographic seizures. Pre-excision ECoG was obtained before and after the administration of 50 micrograms/kg of alfentanil. ECoG was performed using subdural strips placed on the lateral temporal surface and in the suprasylvian region and monopolar depth electrodes implanted into the amygdala and hippocampus. The surgically excised temporal lobes revealed cortical gliosis and varying degrees of hippocampal neuronal loss in all patients. A quantitative assessment of the effect of alfentanil on the ECoG was performed by measuring the frequency of interictal spikes. There was a significant increase in the mesial temporal lobe mean spike frequency after the administration of alfentanil (p < 0.001). One patient had an alfentanil-induced mesial temporal lobe electrographic seizure. Alfentanil did not have a significant effect on spike activity in the suprasylvian region (p = 0.500). Further studies will be necessary to determine the specificity of alfentanil activation in patients with partial seizures of temporal lobe origin.

Adolescent↗

PubMed1993

Prognosis of photoparoxysmal response in nonepileptic patients.

Photoparoxysmal response (PPR) is sometimes incidentally encountered in EEGs performed for evaluation of nonepileptic symptoms. We conducted the first long-term study of a cohort of nonepileptic patients to determine their risk of having seizures subsequent to incidental recording of PPR. After 6 to 12 years (mean, 9 years), none of the 33 patients had had epileptic seizures. To identify prognostic factors associated with PPR, we performed a case-control study comparing the cohort with 33 age-matched patients who had had epileptic seizures prior to PPR recording. There was no statistically significant difference between the two groups with respect to the clinical or EEG data. Morphology of the PPR discharge was not different between the two groups. Contrary to what is widely believed, persistence of PPR discharges beyond stimulation was not associated with a high risk of developing seizures. Prognosis of PPR is age-dependent and seems favorable in adults without previous epileptic seizures.

Adolescent↗

PubMed1986

Techniques and applications of sphenoidal recording.

Sphenoidal electrodes were introduced in the late 1940s and early 1950s to record EEG activity from the inferior mesial temporal region. They are inserted percutaneously beneath the zygomatic arch to rest in the vicinity of the foramen ovale. They are safe, easy to insert, and well tolerated for up to 3 weeks. Artifacts are less prominent than with other types of basal electrodes. Complications are rare. Sphenoidal electrodes are superior to scalp electrodes in detecting interictal epileptiform discharges and ictal EEG patterns from the inferior mesial temporal lobe. Clinical indications include: documentation of epileptiform activity in patients with partial complex seizures in whom scalp recording has been inconclusive; diagnosis of episodes of uncertain mechanism; and localization of an epileptogenic focus in patients being evaluated for temporal lobectomy.

Barbiturates↗

PubMed1986

Temporal lobectomy for partial complex seizures: evaluation, results, and 1-year follow-up.

Twenty-six patients were evaluated for temporal lobectomy. Fourteen underwent initial monitoring with electrodes in the amygdala and hippocampus bilaterally. Twelve had initial monitoring with scalp and sphenoidal electrodes. Four had conclusive localization without depth electrodes. Twenty-three patients underwent lobectomy. At 1-year minimum follow-up, 15 were seizure free. Five had greater than 90% reduction in seizure frequency. Complications of depth electrodes were one hemorrhage and one abscess. One patient developed impaired memory following surgery. Temporal lobectomy is effective in well-selected patients. Depth electrodes localize seizure onset from mesial temporal structures. Scalp and sphenoidal recording may be sufficient in some cases.

Adolescent↗

PubMed1984

Misdiagnosis of complex absence seizures.

Video-EEG monitoring disclosed absence seizures in five patients who were treated for partial seizures. Analysis of the historical and video data showed the presence of several potentially misleading ictal manifestations as follows: unidirectional head and/or eye turning, symmetric clonic activity, urinary incontinence, loss of balance causing injuries, focal clonic activity, and de novo automatisms. Without EEG correlation, complex absence seizures may be difficult to differentiate from other types of seizures. When correctly diagnosed, appropriate therapy may improve seizure control.

Adolescent↗

PubMed1981

Cephalic fibromuscular dysplasia in 32 patients: clinical findings and radiologic features.

The clinical and angiographic features of 32 patients with cephalic fibromuscular dysplasia (FMD) are reported. All of our patients were women, 78% of whom were between 41 and 70 years of age. At examination, 18 (56%) patients had the sudden onset of focal ischemic neurologic deficits. Seven (22%) patients had intracranial berry aneurysms, which ruptured in five patients but were asymptomatic in two. The most common angiographic pattern was the "string of beads" deformity, which involved both extracranial internal carotid arteries at or distal to the third cervical vertebral level. The vertebral artery was affected in six cases, while three cases had intracranial involvement. Less common angiographic findings in this series consisted of segmental fusiform dilation of the artery, and lesions in the form of a septum that extended across the lumen. Twelve patients were followed up for an average of four years. Progression of FMD lesions was shown in two of the six patients who had repeated angiograms. The literature contains reports of only nine cases of cephalic FMD with repeated angiograms, three of which demonstrated progression. Our experience suggests a beneficial role for surgery in patients with specific symptoms in the distribution of the affected vessel, when coexistent disease is negligible or absent.

Adult↗

PubMed1981

Epilepsy in adults.

The past decade has seen advances in the management of patients with epilepsy. The development of practical long-term electroencephalographic techniques, with or without simultaneous video recording, has increased the accuracy of diagnosis of seizure types. The technique also provides clinicians and investigators with a method for establishing the clinical efficacy of antiepileptic drugs and determining their therapeutic serum concentrations. Computerized tomography has enhanced the identification of structural brain lesions. Most of the reported CT abnormalities consist of diffuse and focal atrophies, mild ventricular dilatations, and porencephalies. CT has detected tumors in 8 to 10% of the patients regardless of age or type of seizure involved. New concepts of antiepileptic drug therapy have developed from the recognition of pharmacological properties peculiar to each agent. Determination of serum antiepileptic drug levels has to be utilized to reduce the problem of pharmacokinetic variability from one patient to another and in the same patient at different times, so that dosage can be individualized to achieve maximum therapeutic effects with least toxicity. Review of the literature on pregnancy in epileptic women shows that a third to half experienced more seizures during gestation. Reduced serum levels of most antiepileptic drugs have recently been observed during gestation. Infants of epileptic women taking antiepileptic drugs have a two to three times greater risk for congenital anomalies than infants of nonepileptic women. However, with the exception of oxazolidinediones, evidence to date has not proved the teratogenicity of antiepileptic drugs. The role of genetic factors and the effect of seizures during pregnancy have not been determined. Modest progress has been made in epilepsy rehabilitation, but serious problems still remain. The unemployment rate of persons with epilepsy is twice the national average. Half of those who are successfully employed did not disclose their disorder at the time of employment. Several prognostic indicators have been reported, but the validity of many of these indicators is questionable. For example, does shorter life expectancy apply to all subgroups, or does it vary according to seizure type and cause? The life expectancy, treatment response, and probability of remission in epileptic persons must be reevaluated after consistent applications of current methods of epilepsy management.

Abnormalities, Drug-Induced↗

PubMed1981

Adverse effects of phenytoin on peripheral nerves and neuromuscular junction: a review.

Review of the literature shows that long-term phenytoin therapy is associated with peripheral neuropathy and neuromuscular disorder that rarely can be symptomatic. The usual manifestations of the peripheral neuropathy are lower extremity areflexia, sensory deficits, and reduced conduction velocities. The risk for these peripheral nerve abnormalities is greater with increased serum levels or long duration of therapy (usually more than 5 years). The relative risks according to age groups or number and kinds of antiepileptic drugs used are undetermined. It is not known if detected abnormalities are static or slowly progressive. Isolated case reports have claimed the resolution of signs and symptoms after discontinuance of therapy or correction of a state of intoxication. Appropriate measures to prevent the appearance or progression of the complications are discussed in light of the available evidence.

Action Potentials↗

PubMed1979

Cerebral embolism from septal fibromuscular dysplasia of the common carotid artery.

A rare type of fibromuscular dysplasia of the common carotid artery, in the form of a septum, was observed in a patient suffering from recurrent cerebral infarctions. Angiography demonstrated growth of the lesion and documented the presence of an intraluminal thrombus attached to it. Comparison with reported cases of the more common "string of beads" lesion of fibromuscular dysplasia suggests that the risk for development of ischemic neurological problems is higher for this type of fibromuscular lesion. Surgical correction is recommended, especially for symptomatic patients.

Arterial Occlusive Diseases↗

PubMedDate not supplied

Modified CT techniques in the evaluation of temporal lobe epilepsy prior to lobectomy.

The outcome of temporal lobectomy performed for seizure control is improved by preoperative identification of structural lesions. We used cranial CT, modified to improve visualization of mesial temporal structures, as a means of preoperative evaluation in 48 patients with partial complex seizures. The axial views, parallel to the temporal fossa, improved visualization of five lesions, including two that were not diagnosed by routine cranial CT. In 12 patients, intrathecal metrizamide was used; the rest received intravenous contrast. These modified techniques could not reliably predict mesial temporal herniation; however, modified axial CT with intravenous contrast is recommended for evaluation of suspected temporal lobe pathology.

Brain Neoplasms↗