Bilateral hippocampal atrophy: consequences to verbal memory following temporal lobectomy.

BACKGROUND: Bilateral hippocampal damage is a risk factor for memory decline after anterior temporal lobectomy (ATL). OBJECTIVE: To investigate verbal memory outcome in patients with temporal lobe epilepsy (TLE) with either unilateral or bilateral hippocampal atrophy as measured by MRI. METHODS: The authors selected 60 patients with TLE who had undergone ATL (left = 31, right = 29). They determined normalized MRI hippocampal volumes by cursor tracing 1.5-mm slices from three-dimensional MRI acquisition. Hippocampal volumes were defined as atrophic if the volumes were below 2 SD for control subjects. Bilateral hippocampal atrophy was present in 10 patients with left TLE and 11 patients with right TLE. The authors assessed acquisition, retrieval, and recognition components of verbal memory both before and after ATL. RESULTS: Groups did not differ across age, education, intelligence, age at seizure onset, or seizure duration. Seizure-free rates after ATL were 70% or higher for all groups. Before surgery, patients with left TLE displayed worse verbal acquisition performance compared with patients with right TLE. Patients with left TLE with bilateral hippocampal volume loss displayed the lowest performance across all three memory components. After surgery, both groups of patients with left TLE exhibited worse verbal memory outcome compared with patients with right TLE. Bilateral hippocampal atrophy did not worsen outcome in the patients with right TLE. A higher proportion of patients with left TLE with bilateral hippocampal atrophy experienced memory decline compared with the other TLE groups. CONCLUSION: Bilateral hippocampal atrophy in the presence of left TLE is associated with worse verbal memory before and after ATL compared with patients with unilateral hippocampal volume loss or right TLE with bilateral hippocampal volume loss.

Wisconsin Card Sorting performance in patients with temporal lobe epilepsy: clinical and neuroanatomical correlates.

PURPOSE: A sizable proportion of patients with temporal lobe epilepsy (TLE) display impairments on tests of executive function. Previous studies have suggested several factors that may explain such performance, including the presence of hippocampal sclerosis, electrophysiological disruption to extratemporal regions, and early age of seizure onset. However, no clear determinants have been found that consistently explain such executive dysfunction. The present study investigated the contribution of several clinical variables and temporal lobe neuroanatomic features to performance on the Wisconsin Card Sorting Test (WCST) in a series of patients with TLE. METHODS: Eighty-nine patients with lateralized TLE (47 left, 42 right) were examined. Seventy-two patients from this series underwent anterior temporal lobectomy (ATL). Regression analysis was used to examine the effects of age, education, age at seizure onset, seizure duration, seizure laterality, history of secondary generalized seizures, and MRI-based volumes of the right and left hippocampi on preoperative WCST performance (number of categories completed, perseverative errors). Further univariate analyses examined whether the presence of bilateral hippocampal sclerosis, mesial temporal lobe abnormalities beyond the hippocampus, or temporal neocortical abnormalities affected preoperative WCST performance. In addition, we examined whether becoming seizure free after ATL affected change in WCST performance. RESULTS: Overall regression analysis was not significant. However, an examination of individual partial correlations revealed that patients with a history of secondary generalized seizures performed more poorly on the preoperative WCST than did patients without such history. In addition, patients who were seizure free after ATL did not exhibit better WCST outcome than patients who did not become seizure free. The presence of bilateral hippocampal sclerosis, extrahippocampal mesial temporal atrophy, or temporal neocortical lesions did not affect WCST performance. CONCLUSIONS: These results indicate that the presence of temporal lobe structural abnormalities do not significantly affect executive function as measured by the WCST. The present study does suggests that the critical determinants of WCST performance in patients with TLE lie outside the temporal lobe and likely relate to metabolic disruption to frontostriatal neural network systems.

Investigation of executive function change following anterior temporal lobectomy: selective normalization of verbal fluency.

The nociferous cortex hypothesis predicts that electrophysiological normalization to distal extratemporal brain regions following anterior temporal lobectomy (ATL) will result in improvements in executive functioning. The present study examined the effects of seizure laterality and seizure control on executive function change. The authors administered the Wisconsin Card Sorting Test (WCST), Trails B, and the Controlled Oral Word Association Test to 174 temporal lobe epilepsy patients who underwent ATL. No significant changes were found on the WCST or Trails B tests, regardless of surgery side or seizure-free status. However, verbal fluency significantly improved in seizure-free patients. Findings were consistent with the nociferous cortex hypothesis suggesting selective executive function improvement following ATL. These findings are discussed in terms of recent research demonstrating extrahippocampal metabolic normalization following surgery.

Rasmussen's encephalitis with concomitant cortical dysplasia: the role of GluR3.

The role of the glutamate receptor GluR3 in Rasmussen's encephalitis is actively under investigation. Autoimmune processes with this receptor as the target are currently theorized. We provide an additional case of pathologically proved Rasmussen's encephalitis (with concomitant cortical dysplasia) in the presence of antibodies against the GluR3 receptor.

Individual memory change after anterior temporal lobectomy: a base rate analysis using regression-based outcome methodology.

PURPOSE: To characterize patterns of base rate change on measures of verbal and visual memory after anterior temporal lobectomy (ATL) using a newly developed regression-based outcome methodology that accounts for effects of practice and regression towards the mean, and to comment on the predictive utility of baseline memory measures on postoperative memory outcome. METHODS: Memory change was operationalized using regression-based change norms in a group of left (n = 53) and right (n = 48) ATL patients. All patients were administered tests of episodic verbal (prose recall, list learning) and visual (figure reproduction) memory, and semantic memory before and after ATL. RESULTS: ATL patients displayed a wide range of memory outcome across verbal and visual memory domains. Significant performance declines were noted for 25-50% of left ATL patients on verbal semantic and episodic memory tasks, while one-third of right ATL patients displayed significant declines in immediate and delayed episodic prose recall. Significant performance improvement was noted in an additional one-third of right ATL patients on delayed prose recall. Base rate change was similar between the two ATL groups across immediate and delayed visual memory. Approximately one-fourth of all patients displayed clinically meaningful losses on the visual memory task following surgery. Robust relationships between preoperative memory measures and nonstandardized change scores were attenuated or reversed using standardized memory outcome techniques. CONCLUSIONS: Our results demonstrated substantial group variability in memory outcome for ATL patients. These results extend previous research by incorporating known effects of practice and regression to the mean when addressing meaningful neuropsychological change following epilepsy surgery. Our findings also suggest that future neuropsychological outcome studies should take steps towards controlling for regression-to-the-mean before drawing predictive conclusions.

Phase II study of intracarotid or selective intracerebral infusion of cisplatin for treatment of recurrent anaplastic gliomas.

PURPOSE: To assess the response of patients with recurrent malignant gliomas to intra-arterial (IA) cisplatin. METHODS: Eligibility criteria included patients with recurrent supratentorial malignant gliomas and measurable, unilateral contrast-enhancing tumor located within the territory of one or two major cerebral arteries. Patients received 75 mg/m2 IA cisplatin every four weeks. Depending on individual patients' tumor topography, cisplatin was infused either into the cervical internal carotid artery (ICA) (15 patients), or into one or two major cerebral arteries (26 patients), most often the M1 segment of the middle cerebral artery. RESULTS: Of 40 patients evaluable for tumor response, four patients (10%) were responders and nine patients (22%) had disease stabilization. The median time to tumor progression among the 13 patients with tumor response or stable disease was 23.7 weeks. The response rate did not significantly differ between patients receiving ICA versus selective intracerebral infusion, although the latter group contained a higher proportion of glioblastoma. Tumor progression occurred solely as local failure in 33 patients (82%), with all enhancing tumor still located within the vascular territory infused with IA cisplatin. Ipsilateral vision loss occurred in two patients after ICA cisplatin but in none of the selective infusion patients. Seizures and/or transient or permanent neurologic deterioration occurred in four patients (27%) after ICA cisplatin and in 11 patients (44%) after selective intracerebral infusion. CONCLUSIONS: Although this was not a randomized comparison, selective intracerebral artery cisplatin infusion in this group of patients reduced the risk of eye toxicity, but did not produce a better tumor response rate, and carried a higher risk of neurotoxicity relative to ICA infusion.

Normalization of contralateral metabolic function following temporal lobectomy demonstrated by 1H magnetic resonance spectroscopic imaging.

We studied 10 medically intractable temporal lobe epilepsy (TLE) patients prior to surgery using proton magnetic resonance spectroscopic imaging (MRSI) to localize seizure foci. We found significantly elevated creatine/N-acetylaspartate (Cr/NAA) unilaterally in 8 and bilaterally in 2 patients. Five patients have been studied again 1 year after surgery. In the 2 patients with bilateral temporal seizure onsets, MRSI showed normalization of Cr/NAA in the unoperated contralateral tissue following surgical elimination of seizures. This study suggests that metabolic recovery can occur in contralateral temporal areas following surgical treatment of partial epilepsy.

Dialysis-associated spondylarthropathy. Report of 10 cases.

Ten patients undergoing long-term renal dialysis for end-stage renal failure developed a destructive, non-infectious spondylarthropathy. All 10 patients had biopsy-proven dialysis-associated spondylarthropathy and subsequent spinal instability secondary to beta 2-microglobulin deposition in the vertebrae, intervertebral disc spaces, and support structures of the spine. Nine patients had cervical spinal instability and one had thoracolumbar spinal instability, with resultant neural compression. In at least one patient, the spinal instability was rapidly progressive. All had received renal dialysis for 34 months or longer (mean 109 months, range 34 to 154 months). Each patient required spinal stabilization (external in seven patients, internal in three). Nine of the 10 patients underwent neural decompression and spinal stabilization and fusion procedures. One patient's neurological condition was worse following surgery due to a postoperative cervical epidural hematoma; in the other nine patients, the presenting symptoms and signs improved. Three of these chronically ill patients did not survive their hospitalization, for a perioperative mortality rate of 30%. Death was due to cardiopulmonary arrest in two patients on Day 5 and 9 postoperatively and to sepsis in the third on Day 14. Of the seven early survivors, two additional patients died: one on Day 59 due to congestive heart failure and the other on Day 273 due to a cerebrovascular accident. Four of five patients who were followed for 8 months or longer (mean 14 months, range 8 to 20 months) had successful neural decompression and spinal stabilization procedures with evidence of stable bone fusion, indicating that these chronically ill, difficult-to-manage patients can be successfully treated. Clinicians who treat patients with renal disease and neurosurgeons who treat spinal disorders should be aware of dialysis-associated spondylarthropathy as a potential cause of degenerative vertebral column instability.

Preradiation intracarotid cisplatin treatment of newly diagnosed anaplastic gliomas. The CNS Cancer Consortium.

PURPOSE: This phase II study was performed to assess the response of patients with newly diagnosed, untreated malignant gliomas (anaplastic astrocytoma [AA] and glioblastoma multiforme [GBM]) to intracarotid (IC) cisplatin. PATIENTS AND METHODS: Eligibility criteria included surgical intervention limited to biopsy only, measurable contrast-enhancing tumor, and unilateral tumor location within the vascular territory of one internal carotid artery. Patients were scheduled to receive four infusions of IC cisplatin (75 mg/m2 every 4 weeks) before beginning standard radiotherapy. Twenty-six patients were treated, and 22 were assessable for response. RESULTS: Ten patients (45%) showed a greater than 25% decrease in the enhancing tumor area before radiotherapy with stabilization or improvement of neurologic deficits, and three patients (14%) had a greater than 70% decrease in tumor area. The likelihood of response to IC cisplatin was not clearly linked to patient age, tumor histology, or pretreatment tumor size. Myelosuppression, nephrotoxicity, and ototoxicity were mild. Optic neuropathy occurred in one patient, seizures in two, and fatal postinfusion cerebral edema in one. CONCLUSION: This study design, which permits assessment of the drug sensitivity of the untreated glioma, has shown definite antitumor activity of IC cisplatin in newly diagnosed malignant glioma patients.

The importance of cerebral ischemia during carotid endarterectomy.

The importance of cerebral ischemia produced by carotid clamping during carotid endarterectomy remains controversial. In an effort to determine the importance of cerebral ischemia during carotid endarterectomy, 369 patients undergoing 431 consecutive carotid endarterectomies were studied by Xenon-133 (133Xe) clearance and electroencephalogram (EEG) monitoring. None of the patients was shunted during the procedures. The severity of ischemia as indicated by 133Xe clearance from the ipsilateral hemisphere during 20 to 30 minutes of carotid occlusion did not predict the appearance of complications in this group of patients (chi 2 = 1.417; P = 0.841). There was a highly significant relationship between the depth of cerebral ischemia as demonstrated by 133Xe clearance and the appearance of abnormalities on the EEG (chi 2 = 42.043, P less than 0.0001). In the subgroup of patients developing abnormalities as shown by EEG, there was a negative correlation (chi 2 = 17.495; P less than 0.002) between reduction in blood flow and the appearance of complications, in that the higher the blood flow during occlusion the more likely the patient developing EEG changes would develop complications.

Cortical dysplasia in temporal lobe epilepsy: magnetic resonance imaging correlations.

Cortical dysplasia has been documented in histological specimens surgically removed for treatment of refractory temporal lobe epilepsy. We studied 10 patients with cortical dysplasia and complex partial seizures who underwent temporal lobectomy. Magnetic resonance imaging revealed abnormalities in 5 of the patients who had microscopically detectable major abnormalities. Magnetic resonance imaging revealed an abnormal cortical-white matter architectonic pattern in 2 patients with moderate cortical dysplasia. In the remaining 3 patients, magnetic resonance imaging findings were unremarkable. These observations suggest that magnetic resonance imaging is sensitive in the detection of certain dysplastic lesions in temporal lobe epilepsy. Preoperative identification of these abnormalities by magnetic resonance imaging may permit early and optimal surgical treatment in patients with refractory epilepsy.

Reconstruction of cranial defects with porous hydroxylapatite blocks.

Repair of cranial defects for brain protection and aesthetics is currently a surgical problem for which there is no completely satisfactory solution. Material used for repair of cranial defects should ideally be incorporated by the body and provided a blood supply. No substance to date, including autologous bone, consistently achieves this. Hydroxylapatite is a polycrystalline, nonresorptive, biocompatible ceramic that allows osseous tissue ingrowth and ultimate transformation into vascularized bone. The authors have used granular hydroxylapatite successfully for reconstructing calvarial defects, but have experienced problems with migration of granules, prolonged mobility, and, in one patient, resorption of an underlying supporting bone graft. The use of hydroxylapatite in block form precludes most of these problems. Porous block or strips are easily contoured and can be fixed at the margin of the calvarial defect, providing immediate stability. Ingrowth of osteoblastic and fibrous tissue provides added strength and stability. This paper describes our experience with porous hydroxylapatite blocks for reconstructive cranioplasty.

Multiple complications from an intracranial epidermoid cyst: case report and literature review.

Intracranial epidermoid and dermoid tumors are unusual benign lesions that are potentially curable. Subtotal removal carries a high incidence of recurrence, plus the rare possibility of carcinomatous degeneration of the remnants. Aseptic meningitis from spillage of cyst contents into the subarachnoid space is frequent after operation and has been reported to occur spontaneously. A case of a patient with a posterior fossa epidermoid cyst presenting with multiple bouts of aseptic meningitis in which squamous cell carcinoma arose in recurrent tumor 5 years after subtotal removal of the benign lesion is described.

Blood velocity in the middle cerebral artery and regional cerebral blood flow during carotid endarterectomy.

Blood flow velocity in the middle cerebral artery, determined by transcranial Doppler ultrasonography, was monitored during 31 carotid endarterectomies. Electroencephalogram (EEG) was also monitored, and regional cerebral blood flow (rCBF) was measured. The relation between rCBF and mean velocity was dependent on the rCBF level; the correlation was strong if rCBF was less than 20 ml/100 g/min but weak if rCBF was greater than that level. Ipsilateral EEG suppression was related to a rCBF threshold of 9 ml/100 g/min and to a mean velocity threshold of 15 cm/sec; the rCBF threshold was more specific for EEG change. Postischemic hyperemia was evident in measurements of mean velocity but not of rCBF. These disparities between mean velocity and rCBF seemed to be due to three factors: 1) disproportionately high mean velocity in patients with stenosis of the middle cerebral artery, 2) a nonlinear relation between mean velocity and rCBF, and 3) the anatomically different regions of the brain in which mean velocity and rCBF are measured. The velocity measurement appeared to be relatively more sensitive than rCBF to hemodynamic events in the corpus striatum and internal capsule.

Symptomatic spinal epidural lipomatosis as a complication of steroid immunosuppression in cardiac transplant patients. Report of two cases.

Patients with Cushing's syndrome may develop spinal epidural lipomatosis, an abnormal accumulation of fat in the spinal epidural space. This accumulation of fat may cause compression of the spinal cord or cauda equina with resulting neurological deficit. Two cases of symptomatic spinal lipomatosis are reported in cardiac transplant patients receiving chronic corticosteroid treatment. The literature is reviewed, and diagnostic and therapeutic considerations are discussed.

A prospective analysis of 142 carotid endarterectomies for occlusive vascular disease, 1979-1985.

Carotid endarterectomy may carry a substantial risk of morbidity and mortality from major stroke, thus offsetting any statistical benefit in reduction of future stroke. Because of the disturbing ranges in the incidence of stroke morbidity and mortality reported from the several institutional series studying carotid endarterectomy, the authors undertook a prospective review of 142 consecutive carotid endarterectomies performed for symptomatic atherosclerotic occlusive vascular disease on the neurosurgical service. The University of Alabama Hospital. Preoperative risk assessment was performed in each case according to the Mayo Clinic classification system. The overall mortality rate was 1.4% and the major stroke morbidity rate was 0.7%, for a combined major morbidity and mortality rate of 2.1%. The incidence of minor neurological morbidity was 1.4%. There was no morbidity or mortality in the Grade I and II (low-risk) patient groups. This low combined major morbidity and mortality rate of 2.1% for carotid endarterectomy causes the surgical stroke-free survival curve to intersect the medical stroke-free survival curve at an earlier point in time, and thus demonstrates the greater reduction in risk of stroke which accrues over time for the surgically treated patient.

Focal glial differentiation and oncocytic transformation in choroid plexus papilloma.

The histiopathological features of a choroid plexus papilloma in a 27-year-old male are described. The tumor displayed marked oncocytic transformation and glial differentiation of the epithelium in areas in which there was also marked sclerosis of the fibrovascular cores. Non-membrane-bound bodies of intermediate filaments characterized ultrastructurally the cells with glial differentiation.

Neurosarcoidosis causing ventricular loculation, hydrocephalus, and death.

Ten years after a diagnosis of sarcoidosis, a 33-year-old woman presented with a severe headache of 5 days' duration. Neuroradiologic evaluation revealed a large cystic lesion of the left temporal lobe, causing a mass effect. An exploratory operation proved the lesion to be a loculated portion of the temporal horn of the lateral ventricle. Drainage of the loculated ventricle relieved the patient's cephalgia. Within 2 months, however, pain in the head recurred and an unsteady, broad-based gait appeared. Reevaluation disclosed hydrocephalus for which a ventriculoperitoneal shunt was inserted. After this procedure, the patient did well neurologically for 1 year, after which seizures, personality changes, incontinence, and disturbance of gait developed. Death occurred after revision of the shunt, and widespread granulomatous disease was found at autopsy. Neurosarcoidosis, with emphasis on intracranial mass lesions in sarcoidosis, is discussed; the role of surgical treatment in some of these lesions, and in hydrocephalus, is stressed.

Progressive multifocal leukoencephalopathy: three patients diagnosed by brain biopsy, with prolonged survival in two.

Since 1980, three immunocompromised patients have been proved to have progressive multifocal leukoencephalopathy (PML) by brain biopsy at the University of Alabama at Birmingham. Two patients presented with focal neurological findings, and the third presented with dementia. Computed tomography (CT) revealed white matter low density lesions in areas appropriate to the neurological abnormalities. Brain biopsy of areas that were abnormal on CT produced diagnostic tissue in all three patients. No patient suffered ill effects from the biopsy. Neuropathological findings on light microscopy were compatible with PML in each case, although there was diversity within the group. Involvement of gray and white matter was present in all biopsy specimens; oligodendrocytes, astrocytes, and neurons were affected. Electron microscopic demonstration of particles compatible with polyoma virus confirmed the diagnosis in each case. Immunosuppressive medication was discontinued in two of the patients; these two have survived more than 2 years after diagnosis. One of these two has gradually improved and is independent in simple activities of daily life. Brain stem and cerebellar involvement and seizure disorders have been present in all reported cases. PML can be accurately and rapidly diagnosed by brain biopsy, enabling therapeutic manipulations that may prolong survival.