Default mode network deactivation in pediatric temporal lobe epilepsy: Relationship to a working memory task and executive function tests.

OBJECTIVES: Children with temporal lobe epilepsy (TLE) exhibit executive dysfunction on traditional neuropsychological tests. There is limited evidence of different functional network alterations associated with this clinical executive dysfunction. This study investigates working memory deficits in children with TLE by assessing deactivation of the default mode network (DMN) on functional Magnetic Resonance Imaging (fMRI) and the relationship of DMN deactivation with fMRI behavioral findings and neuropsychological test performance. EXPERIMENTAL DESIGN: fMRI was conducted on 15 children with TLE and 15 healthy controls (age: 8-16 years) while performing the N-back task in order to assess deactivation of the DMN. N-back accuracy, N-back reaction time, and neuropsychological tests of executive function (Delis-Kaplan Executive Function System [D-KEFS] Color-Word Interference and Card Sort tests) were also assessed. PRINCIPAL OBSERVATIONS: During the N-back task, children with TLE exhibited significantly less deactivation of the DMN, primarily in the precuneus/posterior cingulate cortex compared with controls. These alterations significantly correlated with N-back behavioral findings and D-KEFS results. CONCLUSIONS: Children with TLE exhibit executive dysfunction which correlates with DMN alterations. These findings suggest that the level of deactivation of specific functional networks may contribute to cognitive impairment in children with TLE. The findings also indicate that children with TLE have network alterations in extratemporal lobe brain regions.

Periodic Lateralized Epileptiform Discharges (PLEDs) in Patients With Neurosyphilis and HIV Infection.

Periodic lateralized epileptiform discharges (PLEDs) are an electroencephalographic pattern recorded in the setting of a variety of brain abnormalities. It is best recognized for its association with acute viral encephalitis, stroke, tumor, or latestatus epilepticus. However, there are other conditions that have been recognized as the underlying pathology for PLEDs such as alcohol withdrawal, Creutzfeldt-Jacob disease, anoxic brain injury, and hemiplegic migraine. However, there are only rare case reports of PLEDs in patients with neurosyphilis. Here, we report 2 patients presenting with encephalopathy and seizures with PLEDs, ipsilateral or contralateral to their main brain magnetic resonance imaging abnormalities. Further workup revealed neurosyphilis in both patients, one in association with human immunodeficiency virus (HIV) infection. Given the increasing incidence of neurosyphilis with or without HIV infection, these cases suggest neurosyphilis as a consideration in the differential for patients presenting with PLEDs.

Successful ECT treatment for medically refractory nonconvulsive status epilepticus in pediatric patient.

Status epilepticus is a life threatening condition with a high mortality rate in spite of aggressive treatment. There is little consensus on third and fourth line approaches in refractory cases. While electroconvulsive therapy (ECT) has been employed successfully as a treatment for refractory epilepsy and status epilepticus (SE) after exhausting conventional therapy, its use for pediatric patients is limited. We describe a 7-year-old pediatric case in which ECT was used successfully to treat medically refractory nonconvulsive status epilepticus (NCSE) without complete withdrawal of antiepileptic drugs (AED).

Somatosensory evoked potential monitoring of the brachial plexus during a Woodward procedure for correction of Sprengel's deformity.

Sprengel's deformity is the most common congenital deformity of the shoulder. A known complication of correcting this deformity is brachial plexus palsy. In this study we used somatosensory evoked potential (SSEP) monitoring during correction of a Sprengel's deformity and identified an early iatrogenic brachial plexus injury. The operation was modified, and permanent nerve injury was avoided. We recommend that SSEP monitoring be considered in procedures to correct Sprengel's deformity.

Zonisamide concentrations during pregnancy.

OBJECTIVE: To describe a series of serum concentrations of zonisamide in a pregnant woman. CASE SUMMARY: A 30-year-old woman with primary generalized tonic-clonic seizures and myoclonic jerks was taking zonisamide 200 mg daily as her sole antiepileptic agent when she conceived. She continued on zonisamide throughout her pregnancy. The zonisamide concentrations ranged between 7.5 microg/mL and 17 microg/mL during pregnancy, with the exception of a 4.4-microg/mL concentration at 27 weeks postconception. Following this lower concentration, the zonisamide dose was increased to 300 mg/day at week 29. She had an uneventful pregnancy, with only occasional myoclonic jerks, and delivered at 41 weeks. At 42 weeks, while taking zonisamide 300 mg/day, her concentration was 20.8 microg/mL. DISCUSSION: A single report from Japan reviewed 26 cases of prenatal exposure to zonisamide. Twenty-two offspring were exposed to zonisamide monotherapy; 4 were exposed to polytherapy. During the first trimester, 2 pregnant women on zonisamide and at least one other antiepileptic medication had serum concentrations of 6.1 microg/mL and 6.2 microg/mL; 2 of the infants had teratogenic effects. Teratogenicity has also been reported in animals. There are no other published data regarding zonisamide concentrations during pregnancy. CONCLUSIONS: The change in zonisamide serum concentrations in a pregnant woman suggests an increase in clearance at the end of the second trimester.

Gabapentin-induced myoclonus in end-stage renal disease.

PURPOSE: We analyzed the occurrence and clinical features of myoclonus in patients with end-stage renal disease (ESRD) who were treated with gabapentin (GBP). METHODS: We reviewed the medical records of patients with ESRD who were treated with GBP and hospitalized during an 18-month period and analyzed clinical details such as type of myoclonus, doses of GBP, electroencephalographic (EEG) findings, and relation of symptoms to GBP exposure and dosage. RESULTS: Three of 71 patients had myoclonus with GBP doses ranging from 9 mg/kg to 20 mg/kg and within 4 months of treatment onset. Myoclonus was characterized as multifocal, involving all extremities in the three patients. EEG did not show epileptiform discharges with the myoclonus. Myoclonus resolved in the three individuals within 4-15 days after GBP was discontinued. CONCLUSIONS: GBP increases the risk of myoclonus in ESRD. Myoclonus in these individuals was more disabling than that in patients with normal renal function, and discontinuation of GBP is required to restore normal function.

Dysphonia associated with carotidynia and migraine responding to dihydroergotamine.

Carotidynia is characterized by throbbing pain over the carotid artery and may be caused by migraine. We report a case of a 54-year-old woman with recurrent dysphonia associated with carotidynia and other features of atypical migraine that resolved after treatment with dihydroergotamine. To our knowledge, this is the first report of dysphonia associated with migraine.

Assessment and cost comparison of sleep-deprived EEG, MRI and PET in the prediction of surgical treatment for epilepsy.

Our aim was to determine if less expensive interictal indices can predict which epilepsy patients may benefit from the more expensive comprehensive pre-surgical evaluation. Surgical treatment was determined based on the results of a comprehensive inpatient continuous video-EEG monitoring. This evaluation included three interictal tests, which were reviewed retrospectively-2 hour-sleep-deprived electroencephalogram (SDEEG), magnetic resonance imaging (MRI), and positron emission tomography (PET). Sixty-nine patients were evaluated with 35 patients having focal resection (33 temporal, two frontal). When two or more interictal tests were positive, 77% (27 /35) went to surgery, but when one test was positive 23% (8 /34) had surgery. When all tests were negative, only a single patient (1 /13 or 7.7%) had surgery, a frontal resection. The positive predictive value for any single interictal test was 68%, while it was higher for any combination of two positive tests (77-83%). PET was the most sensitive (0.86) single interictal test, compared to SDEEG (0.66) and MRI (0.66). The odds ratio for predicting surgical treatment for a positive PET, SDEEG, or MRI was 8.57, 4.01, and 4.01, respectively. MRI was three and PET was six times the cost of a SDEEG. The combination of SDEEG and MRI had the best cost/PPV ratio. Seventy-nine percent (11 /14) of the patients with three positive tests were seizure free following focal resection compared to 43% (9 /21) when less than three tests were positive ( P