Kazuo Okanari

Rapid eye movement sleep reveals epileptogenic spikes for resective surgery in children with generalized interictal discharges.

Epilepsy surgery can be successful in children with extensive congenital or early acquired focal or hemispheric brain lesion on magnetic resonance imaging (MRI) despite generalized interictal epileptiform discharges (IEDs). The aim of this study was to assess if rapid eye movement (REM) sleep reduced generalized IEDs and revealed lateralized IEDs to identify the epileptogenic hemisphere in children with generalized IEDs and normal/subtle changes on MRI.

Increased subcortical oligodendroglia-like cells in pharmacoresistant focal epilepsy in children correlate with extensive epileptogenic zones.

Cortical resections in epilepsy surgery tend to involve multiple lobes in children, compared to adults, partly due to underlying pathology. Oligodendroglia‐like cells (OLCs) have been observed in surgical specimens from children with pharmacoresistant epilepsy. We hypothesize that OLCs recruit multiple‐lobe epileptogenic zones in pediatric pharmacoresistant focal epilepsy.

Asymmetrical generalized paroxysmal fast activities in children with intractable localization-related epilepsy

BACKGROUND Generalized paroxysmal fast activity (GPFA) consists of burst of generalized rhythmic discharges; 100-200 μV; 1-9s; 8-26 Hz; with frontal predominance; appearing during NREM sleep. GPFA was originally described as an electrographic feature of Lennox-Gastaut Syndrome (LGS). We analyzed GPFA on scalp video EEG (VEEG) in children to evaluate that GPFA presents in patients with intractable localization-related epilepsy. METHODS We collected cases with GPFA with intractable localization-related epilepsy who underwent scalp VEEG, MRI, and magnetoencephalography (MEG) prior to intracranial video EEG (IVEEG) and surgical resection. We collected 50 epochs of GPFA per patient during the first night during scalp VEEG. We analyzed amplitude, duration and frequency of GPFA over the bilateral frontal region between surgical resection side with grid placement and non-resection side. RESULTS We identified 14 (14%) patients with GPFA on scalp VEEG. The mean amplitude ranged from 145 to 589 μV (mean 293 μV). The mean duration ranged from 1.18 to 2.31s (mean 1.6s). The mean frequencies ranged from 9.3 to 14.7 Hz (mean 11.1 Hz). The amplitude (307 ± 156 μV) and duration (1.62 ± 0.8s) of GPFAs in all the patients over the resection side were significantly higher than those (279 ± 141 μV, 1.58 ± 0.8s) of the non-resection side (p<0.001). All nine patients who showed significant duration differences between two hemispheres (p<0.05) had longer duration of GPFA over the resection side. Eight of 12 patients who showed significant amplitude differences between two hemispheres (p<0.05) had higher amplitude of GPFA over the resection side. Four of six patients who showed significant frequency differences between two hemispheres (p<0.05) had higher frequency of GPFA over the resection side. Nine (64%) patients became seizure free after surgical resection including multilobar resections in eight patients. CONCLUSIONS GPFA can exist in localization-related epilepsy with secondary bilateral synchrony. Although EEG shows GPFA on scalp VEEG, the precise localization of the epileptogenic zone using IVEEG could achieve the successful surgical resection.

Hemimegalencephaly in a Patient With Coexisting Trisomy 21 and Hypomelanosis of Ito

A male infant with trisomy 21 simultaneously showed clinical features of hypomelanosis of Ito and hemimegalencephaly, with related intractable epileptic seizures. The epileptic seizures were refractory to conventional antiepileptic drugs and persisted until the patient underwent functional hemispherotomy. It is well known that patients with hypomelanosis of Ito may also have cortical dysplasia and hemimegalencephaly and that approximately half of these patients have chromosomal abnormalities. However, to our knowledge, there is no previous report of a patient with trisomy 21 associated with hemimegalencephaly. Here, we describe a rare case of coexisting trisomy 21 and hypomelanosis of Ito, associated with hemimegalencephaly.

Reversible cerebral vasoconstriction syndrome manifesting as focal seizures without a thunderclap headache: A pediatric case report

We report a pediatric case of reversible cerebral vasoconstriction syndrome with focal seizures without a thunderclap headache. A 7-year-old girl had a mild acute headache with nausea after swimming. She subsequently developed hemi-convulsions followed by right hemiplegia. Brain magnetic resonance angiography revealed generalized vasoconstriction of the main cerebral peripheral arteries. Her hemiplegia was spontaneously resolved within 6h. Over the next 24h she suffered from recurrent and transient headaches, which recurred on days 3 and 5. Follow-up magnetic resonance angiography on day 3 documented the multifocal narrowing of the main cerebral arteries, which was observed to have diminished at 12weeks after her initial presentation. She did not have any headaches or neurological deficits after day 5. This case indicates that reversible cerebral vasoconstriction syndrome should be considered in children with focal seizures even when they do not present with thunderclap headaches. The timely and appropriate evaluation by magnetic resonance angiography and imaging is essential for diagnosing reversible cerebral vasoconstriction syndrome.

A severe pulmonary complication in a patient with COL4A1-related disorder: A case report

Patients with COL4A1 mutation-related disorders demonstrate a variety of disease phenotypes, which caused by small-vessel dysfunction in the brain, eyes, kidney, muscle, or heart. The involvement of organs mainly depends on the expression of the COL4A1 gene. Complication or dysfunction of the alveolar tissue has not been reported in the literature on COL4A1 mutation-related disorders. We herein report the case of a boy with schizencephaly, renovascular hypertension, and retinal arteriosclerosis of unknown origin, who suffered from severe and repetitive alveolar hemorrhage at 9 years of age. A novel COL4A1 mutation was finally identified as the genetic cause. The pulmonary complication in the present case represents an important pathophysiological mechanism COL4A1 mutation-related disorders; lung tissue with COL4A1 gene mutations may be vulnerable and environmental substances and microorganisms in the air could accumulate to cause chronic damage in the alveolar tissues, especially in patients with tracheostoma and renovascular hypertension.

Progressive Dysautonomia in Two Patients With Xeroderma Pigmentosum Group A

BACKGROUND Xeroderma pigmentosum group A (XPA) is a rare autosomal-recessive disorder caused by a defect in nucleotide excision repair. Progressive dysautonomia in patients with XPA is rarely described. PATIENTS Two juvenile male patients with XPA suffered from dysphagia, sleep interruption, and dysuria from the age of 10 to 19 years, successively. These autonomic symptoms might have been caused by progressive descending degeneration of cranial nerves IX and X and the sacral parasympathetic nerve, including Onufs nucleus. One patient died from sudden cardiopulmonary arrest during postural change and tracheal suction. RESULTS Heart rate variability analyses of these patients revealed parasympathetic dysautonomia, based on decreased high-frequency values. CONCLUSIONS The insidiously progressive dysautonomia in these two patients with XPA suggested progressive descending degeneration extending from the medulla oblongata to the sacral spinal cord, which is an ominous sign of end-stage disease and a risk factor of sudden death attributable to XPA.

Pediatric nondura-based clear cell meningioma of the cauda equina: case report and review of literature

Abstract Although spinal meningiomas are uncommon in children, clear cell meningioma has been described as the most common variant of spinal meningiomas in the pediatric age group. 24 cases of pediatric spinal clear call meningioma have been reported in the literature. We report one case and review the literature regarding pediatric spinal clear cell meningioma.

Intraoperative Neurophysiologic Monitoring for Prediction of Postoperative Neurological Improvement in a Child With Chiari Type I Malformation

Introduction: Although many surgical treatment strategies for Chiari malformation type I (CM-I) have been reported, the most appropriate surgical technique remains controversial. It is wholly ascribable to the complicacy of pathological condition in CM-I. Recently, intraoperative neurophysiologic monitoring (INM) is becoming prevalent in spinal surgery. Indeed, motor-evoked potentials (MEPs) monitoring and somatosensory-evoked potentials (SSEPs) monitoring are standard tools to minimize the risk of neurologic injury and postoperative deficits. The most recent study suggested that multimodality INM can be beneficial in foramen magnum decompression surgery for CM-I patients for surgical positioning and planning. Various authors have investigated the consistency of intraoperative evoked potential changes that might aid the surgeon to determine the appropriate extent of decompression required for an individual patient. Patient Description: The authors report the case of a 7-year-old boy who had the signs of medullary and cerebellar dysfunction, clumsy hands, and ataxic gait. He underwent a surgery of foramen magnum decompression with tonsillectomy and duraplasty for CM-I with cervicomedullary compression. His intraoperative MEPs improved (indicated increased-amplitude and shortened-latency) both after craniotomy and durotomy, whereas SSEPs improved only after durotomy. Those results were correlated well with a functional improvement that was apparent in the immediate postoperative hospitalization. Conclusions: The authors’ data provides 1 possible interpretation of INM for safety aspect, but also which degree of decompression in each patient will require. The improvement in MEPs and SSEPs observed during decompression procedure may be a good indicator for the prediction of the clinical improvement seen postoperatively.

Steal phenomenon in Sturge-Weber syndrome imitating an ictal electroencephalography change in the contralateral hemisphere: report of 2 cases

Infants with Sturge-Weber syndrome (SWS) are considered for surgery if they develop seizures and the seizures prove medically refractory. The authors report on 2 infants (15 and 19 months old) with SWS who underwent scalp video electroencephalography (EEG) and subsequent functional hemispherotomy for intractable partial motor seizures due to extensive left hemispheric angiomatosis. They presented with similar interictal and ictal EEG findings. Ictal EEG showed abrupt high-amplitude delta slow waves, without evolution on the contralateral hemisphere before the build-up of ictal EEG changes on the lesional hemisphere. The patients became seizure free after hemispherotomy. The ictal contralateral slow waves were not a sign of an ictal hemisphere and may indicate prominent ischemic changes resulting from a steal phenomenon of hemispheric angiomatosis during seizure.