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Summary: Purpose:We investigated the association of severity of hypometabolism detected by positron emission tomography (PET) with [18 F]fluorodeoxyglucose (FDG) and persistence of interictal EEG focal slowing in patients with refractory temporal lobe epilepsy.Methods: Eighty temporal lobes of 40 consecutive patients with intractable temporal lobe epilepsy (mean age, 43.5 years) were studied. All patients underwent video-EEG monitoring, magnetic resonance imaging (MRI), and FDG-PET. Patients with either normal MRI or with unilateral mesial temporal sclerosis, but no other structural abnormality, were included. Interictal EEG delta slowing was graded as none, infrequent (one episode or less/hour), intermediate (more than one episode/hour), or continuous. PET hypometabolism was graded as none, mild, moderate, or severe.Results: The severity of temporal lobe hypometabolism with PET was significantly correlated with the amount of delta activity in the interictal EEG, independent of MRI findings (Spearman r = 0.46; p < 0.0005).Conclusions: This observation suggests related underlying pathophysiologic mechanisms for metabolic and electrical dysfunction in temporal lobe epilepsy. Key Words: PET hypometabolism-EEG delta slowing-Temporal lobe epilepsy.Interictal positron emission tomography (PET) with [ 18 F]fluorodeoxyglucose (FDG) lateralizes the primary epileptogenic temporal lobe in 60 to 90% of patients with intractable temporal lobe epilepsy (1). Prior studies indicated that qualitatively measured interictal hypometabolism is a reliable prognostic factor for seizure outcome after temporal lobectomy (2), although quantitative measurements of hypometabolic areas in the temporal lobe(s) offer more precise results for metabolic abnormality (3). The underlying pathophysiologic mechanisms of the presence and extent of hypometabolism in temporal lobe epilepsy are not fully understood. Interictal focal delta slowing also is described as a reliable lateralizing finding in nonlesional refractory temporal lobe epilepsy and provides additional evidence of an underlying epileptogenic zone (4). However, regional delta activity has been associated with structural abnormalities in subcortical white matter (5). The pathophysiologic mechanism No consistent correlation has been demonstrated between the severity of hippocampal sclerosis and interictal PET hypometabolism (6,7). Likewise, no relation has been found between interictal PET hypometabolism and focal delta slowing in patients with refractory epilepsy and hemispheric tumors (8). More fully to understand the relation between electrophysiologic and metabolic disturbances in temporal lobe epilepsy, we analyzed the correlation of the degree of interictal EEG slowing with the severity of hypometabolism seen on FDG-PET in patients with temporal lobe epilepsy without a space-occupying lesion. METHODSWe retrospectively evaluated clinical, neuroimaging, and video-EEG monitoring findings of both temporal lobes of 40 consecutive patients (age 20 to 67 years; mean age, 43.5 years; 22 wom...

Transient signs and symptoms of CNS involvement have been reported in Charcot-Marie-Tooth disease type 1X (CMT1X). 1,2 We describe a patient with CMT1X and chronic progressive-relapsing inflammatory demyelinating CNS disease.Case report. A 44-year-old man was admitted because of subacute onset of gait ataxia, dysphagia, and dysarthria. He had experienced worsening stepping gait for the previous decade, and an EMG examination a year and a half before presentation had shown a demyelinating sensorimotor neuropathy. Otherwise, his medical history was unremarkable. Neurologic examination showed a wide based gait with ataxia worsening after eye closure, upper limb incoordination, and gaze-evoked nystagmus. There was weakness of foot dorsiflexion and toe extension. Tendon reflexes were absent. The patient was dysarthric and had dysphagia for liquids. EMG showed a mixed axonal-demyelinating polyneuropathy (table E-1 on the Neurology Web site at www.neurology. org). Visual evoked potentials (VEPs) were normal, whereas brainstem auditory potentials (BAEPs) showed alterations bilaterally (table E-1). Brain MRI showed multiple T2-hyperintense lesions in the pons, paraventricular region, and corpus callosum (see figure, A through C), without gadolinium (Gd) enhancement. Analysis of CSF showed increased protein content (82 mg/dL) with normal cell count. Oligoclonal IgG bands restricted to CSF were also detected. Sural nerve biopsy showed onion bulbs and loss of myelinated fibers, without inflammatory infiltrates. The patient was treated with IV methylprednisolone 1 g/day for 5 days, without appreciable benefit. One month later, during rehabilitation, he suddenly developed bilateral loss of visual acuity. VEPs showed marked prolongation of P100 wave latency (table E-1). He was treated again with IV methylprednisolone 1 g/day for 5 days, without benefit. Three years later, he was again admitted to our hospital. The neurologic examination showed severe gait ataxia which confined the patient to a wheelchair, and severe incoordination of upper limbs with marked action tremor. Dysarthria and dysphagia were moderate. Muscle strength was normal except for moderate weakness of tibialis anterior, extensor hallucis, and dorsal interossei. Urinary retention was also present. Brain MRI scans demonstrated increased T2-lesion load and one Gdenhancing lesion in the pons (figure, D). BAEPs and VEPs were unchanged. Treatment with IV immunoglobulins (0.4 g/kg/day) was withdrawn after 2 days because of hematuria. DNA analysis showed the mutation c490 CϾT, R164W in the GJB1 gene. The family history was reassessed. A brother showed stepping gait with bilateral severe deficit of ankle dorsiflexion and, to a lesser degree, plantar flexion. EMG showed a mixed sensorimotor polyneuropathy with conduction velocities in the same range of the index case. BAEP and VEP were unremarkable. Brain MRI was normal. Genetic analysis showed the same mutation of GJB1 gene identified in the index case.Discussion. Our index patient showed a CNS demyelinating disease th...

Refractory status epilepticus is a devastating persistent seizure state with a poor prognosis that requires emergency medical management. Recent studies have reported de novo, idiopathic refractory status epilepticus of unclear etiology in healthy young patients followed by severe neurologic sequelae. We present a series of 7 cases of de novo sustained refractory status epilepticus. We found that all patients were young and previously healthy and that, prior to the onset of refractory status epilepticus, all had prodromal viral-like symptoms. The onset of refractory status epilepticus was explosive and intractable, resulting in prolonged hospital stay and dependence on multiple antiepileptic medications. Clinical outcome was poor in all 7 patients. The laboratory findings suggest a possible immune activation that can have persisted in the nervous system after a nonspecific infection. We report on these patients so as to raise awareness of this unique entity to facilitate early diagnosis and treatment.

Background: Central pontine myelinolysis (CPM) is a demyelinating disorder most frequently described in alcoholism and malnourishment after rapid correction of hyponatremia affecting the pontine base. We present a case of reversible CPM as demonstrated on neuroimaging and at autopsy in a patient with recent upper respiratory infection and vitamin B12 deficiency. Case persentation: Patient presented with lower extremity weakness after upper respiratory infection. She had a normal sodium level, but found to have low vitamin B12 level. MRI of the brain showed restricted diffusion in the pontine basis. She was given empiric prednisone for myopathic symptoms and vitamin B12 supplementation for her low level. She made full clinical recovery by 5 months. She developed pneumonia 6 months after initial presentation. Repeat MRI showed resolution of the hyperintensity in the pontine basis. Her respiratory status worsened, and she died. At autopsy, there was no evidence of demyelination in the pontine basis. Conclusion:The importance of this case is that in CPM not associated with hyponatremia the radiologicalpathological correlation of osmotic demyelination can be completely reversible.