Relevance of residual histologic and electrocorticographic abnormalities for surgical outcome in frontal lobe epilepsy.

Purpose: To estimate the significance of residual electrocorticographic and neuropathologic abnormalities on seizure control after surgery for frontal lobe epilepsy with the purpose of determining their relevance in deciding the extent of the surgical procedure.

Methods: The presence of epileptiform discharges in intraoperative electrocorticograms (ECoGs) and the nature and extent of neuropathologic abnormalities were reviewed for 35 patients who underwent frontal lobe resections for the treatment of epilepsy at our institution. The relations between surgical outcome and presence of the following features were studied: (a) presence of abnormal tissue at the limits of the resection; (b) presence of sporadic spikes and seizure patterns in the preresection ECoG; (c) their abolition in the postresection ECoG; and (d) the topography of residual discharges with respect to the margins of the resection.

Histological heterogeneity of dysembryoplastic neuroepithelial tumour: identification and differential diagnosis in a series of 74 cases.

Aims: In a retrospective study of resected specimens from 416 patients being treated for long-standing epilepsy, 74 cases of dysembryoplastic neuroepithelial tumour (DNT) were encountered that were all characteristically composed of small round oligodendroglia-like cells (OLC), astrocytes and mature neurones in varying proportions. The architectural patterns, histological, immunohistochemical and ultrastructural features and results of cell proliferation studies and postoperative follow-up are described to facilitate the identification of DNT and to differentiate it from other intrinsic neoplasms that commonly present with seizures.

Methods And Results: The tumours presented with early onset of seizures, at a median age of 7 years, without the signs of raised intracranial pressure.

A clinicopathological study of autism.

A neuropathological study of autism was established and brain tissue examined from six mentally handicapped subjects with autism. Clinical and educational records were obtained and standardized diagnostic interviews conducted with the parents of cases not seen before death. Four of the six brains were megalencephalic, and areas of cortical abnormality were identified in four cases.

Autosomal-dominant dentatorubropallidoluysian atrophy in the United Kingdom.

Dentatorubropallidoluysian atrophy (DRPLA) has been described chiefly in Japan and appears to be rare in Europe. It is of autosomal dominant inheritance. We report the first British family with DRPLA, which contains four affected individuals in two generations.

Electrocorticography and stimulation.

Although acute electrocorticography (ECoG) is routinely used during epilepsy surgery there is little agreement as to its value nor criteria for its interpretation. Specific issues are reviewed on the basis of the literature and personal studies: does failure to resect the entire irritative zone prejudice seizure control, and are residual discharges predictive of failure; does activation of the ECoG by intravenous barbiturates provide information of clinical value; does intraoperative electrical stimulation help to improve localisation or avoid postoperative deficits; is the ECoG of value for monitoring functional procedures; can the value of ECoG be increased by new interpretive approaches? It is suggested that resection of the entire area of interictal discharge is not essential for satisfactory surgical outcome, but a distinction may need to be made between those discharging regions that function as pacemakers and those in which ECoG spikes appear secondarily. There is also evidence that, apart from any consideration of determining the area resected, the topography of epileptiform discharge may be predictive of pathology and surgical outcome.

Surgical treatment of epilepsy due to cortical dysplasia: clinical and EEG findings.

Seventeen patients with cortical dysplasia who had surgical resection for medically intractable partial epilepsy were studied. Compared with two groups of surgically treated patients with intractable epilepsy due to tumour (n = 20) and mesial temporal sclerosis (n = 40), patients with cortical dysplasia showed significantly more frequent extratemporal lesions, more frequent non-epileptiform EEG abnormalities and less favourable surgical outcome for seizure control. Patients with cortical dysplasia were younger at onset of seizures and had a lower detection rate of CT abnormalities compared with the tumour group, and lower IQ compared with the mesial temporal sclerosis group.

Late fetal pontine destruction.

A child with an absent pons is described who died 8 weeks after birth. At postmortem examination, the defect was consistent with a vascular event in the last trimester.

Cerebral aspergilloma in a child with autosomal recessive chronic granulomatous disease.

A 2 year old girl presented with epilepsy 16 months after being diagnosed as having autosomal recessive chronic granulomatous disease. Computed tomography showed a cerebral mass which was surgically removed and proved histologically to be an aspergilloma. This case illustrates the application of molecular diagnostic techniques to the diagnosis of chronic granulomatous disease.

Control of temporal lobe epilepsy following en bloc resection of low-grade tumors.

Thirty-one patients with a mean age of 18.9 years (range 3 to 53 years) who underwent temporal lobe surgery for tumor-related epilepsy over a 14-year period are presented. All had suffered chronic drug-resistant temporal lobe seizures (mean age at onset 6.

Prion protein immunocytochemistry helps to establish the true incidence of prion diseases.

Creutzfeldt-Jakob disease (CJD) and Gerstmann-Strüssler-Scheinker disease (GSSD) are transmissible spongiform encephalopathies or prion diseases affecting man. It has been reported that prion diseases may occur without the histological hallmarks of spongiform encephalopathies: vacuolation of the cerebral grey matter, neuronal loss and astrocytosis. These cases without characteristic neuropathology may go undiagnosed and consequently the true incidence of transmissible dementias is likely to have been under-estimated.

Beta A4 deposition in the temporal cortex of adults with Down's syndrome.

The deposition of beta A4 has been quantified in the temporal cortex of 9 adults (4 male, 5 female) with Down's syndrome (DS), mean age (+/- SD) 54.7 +/- 8.8 years (range 41-67 years) at the time of death.

Rasmussen's encephalitis in surgery for epilepsy.

Nineteen patients with Rasmussen's encephalitis were studied, using light-microscopy, immunohistochemistry and in some cases electron-microscopy. Although there was inflammation, no causative agent was identified. 10 patients underwent hemispherectomy and with one exception did well, while local resection for seven produced little or no improvement.

Neuropathology of biotinidase deficiency.

A patient with biotinidase deficiency and a progressive neurological disorder died just before the biochemical diagnosis was established. Post-mortem examination of the brain and spinal cord revealed necrotising lesions similar to those in Leigh's disease and Wernicke's encephalopathy. Unlike these two conditions, the regions affected included the hippocampus and parahippocampal cortex.

Predictive value of intraoperative electrocorticograms in resective epilepsy surgery.

The preresection and postresection intraoperative electrocorticograms of 76 consecutive patients undergoing resective surgery for intractable epilepsy were analyzed to see if location, configuration, and discharge rate of epileptiform activity correlated with type and location of pathology of the resected specimens and outcome in regard to seizure control. The location of the predominant spike focus did not correlate with either type of location of pathology or with seizure outcome from temporal lobe surgery (n = 58). The presence of spontaneous or activated spikes outside the resected area did not correlate with outcome from any surgery type.

Prion dementia without characteristic pathology.

Gerstmann-Sträussler syndrome (GSS) was diagnosed in a family with presenile dementia by prion protein gene analysis. Extensive histological examination of the brain of an affected individual from this family showed no characteristic features of GSS or Creutzfeldt-Jakob disease (CJD). Thus "spongiform encephalopathy" (GSS or CJD) cannot always be excluded on neuropathological grounds in an individual dying of a dementing condition, and the true prevalence of these diseases is likely to be underestimated.

Neuropathologic correlates of leuko-araiosis.

We describe the pathologic findings in 17 persons with dementia, 12 of whom exhibited leuko-araiosis on computed tomographic scan. The presence of white matter pallor was confirmed on autopsy in 11 of these 12 cases, 9 with Alzheimer's disease and 2 with multi-infarct dementia. Two further patients, 1 with Alzheimer's disease and 1 with multi-infarct dementia, proved to have white matter changes on pathologic examination.

Acute hippocampal recording and pathology at temporal lobe resection and amygdalo-hippocampectomy for epilepsy.

An electrocorticographic (ECoG) study is reported of patients undergoing surgery for epilepsy of temporal lobe origin. During 22 en bloc resections and six out of a total of 18 amygdalo-hippocampectomies, the activity of the hippocampus was also recorded by a multipolar strip electrode placed along its axis on the ventricular surface. Patients with mesial temporal pathology, chiefly mesial temporal sclerosis, made up the majority of those selected for amygdalo-hippocampectomy.

Cortical Lewy body dementia: clinical features and classification.

Seven patients, aged 65-72 years, are described with dementia and cortical Lewy bodies. In one patient a Parkinsonian syndrome was followed by dementia and motor neuron disease. In the remaining six patients dementia was accompanied by dysphasia, dyspraxia and agnosia.

Persistent mercury in nerve cells 16 years after metallic mercury poisoning.

A male subject, after exposure to mercury metal at work in 1968, developed classical signs of mercurialism from which he made a slow clinical recovery. He subsequently developed psychoneurotic symptoms and became an alcoholic; he never returned to work and died in 1984. No histological changes relevant to mercury intoxication were found in the brain, but staining by Danscher & Schroeder's method for mercury showed many positively staining lysosomal dense bodies in a large proportion of nerve cells, and the presence of mercury was confirmed by elemental X-ray analysis.

Adult polyglucosan body disease (APBD).

Three patients aged 63, 63 and 74 years had various combinations of progressive lower and upper motor neuron dysfunction, sensory loss, urinary incontinence and dementia. Postmortem examinations in two cases showed moderate cerebral and spinal atrophy, ill-defined areas of incomplete myelin loss in white matter and small necrotic foci in the white matter of gyri, around the basal ganglia and near the dentate nuclei. The main microscopic abnormality was a massive accumulation of PAS-positive polyglucosan bodies (PB) of various sizes and shapes in the cerebral hemispheres, brainstem, cerebellum, spinal cord, nerve roots and nerves.

Early-onset Huntington's chorea. Diagnostic clues.

A patient with early-onset Huntington's chorea is described. The diagnosis had been overlooked during previous contacts with psychiatric services because there was no family history, and features typical of the adult disease were absent. Distinctive findings on CT scan and electroencephalography were observed.

Relationships between neuropathology and cognitive functioning in temporal lobectomy patients.

Cognitive functions were examined before operation and 4 weeks after operation with respect to pathology in 40 patients who underwent temporal lobectomy for epilepsy. Hippocampal sclerosis was associated with febrile convulsions, an earlier onset of regular seizures, poorer preoperative intelligence and with a tendency towards greater cognitive improvement across the operation than found in patients with tumour-like malformations or non-specific pathology. Damage to the amygdala was associated with a poorer outcome for the retention in memory of verbal and non-verbal material.