We investigated mortality patterns of severely retarded children who were cared at their homes in Tokyo ten years after our first report. During the past two and a half years (from April 1999 to September 2001), we identified 41 fatal cases. The annual case fatality rate (the mortality rate among the investigated children) was 8.2 %o in all the school-attending children and was 10.1 % in children with severe motor and intellectual disabilities. The rate was less than half of that in our past report and seemed to be the lowest among those in several studies. Aggravation of basal disorders, severe respiratory infections and/or sepsis, and unexplained sudden death accounted for most of the death. We conclude that advance of medical service and the propagated medical education of teachers working for special schools play an important role to reduce the mortality in severely retarded children.

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Although some recent studies have reported various cognitive impairments and behavioral disorders in children having benign childhood epilepsy with centrotemporal spike (BCECT), it is still commonly believed that BCECT does not cause any definite neuropsychological impairment. In addition, reported impairments range over various cognitive functions, and there is no general agreement on this issue.
We performed detailed neuropsychological tests in 17 children with BCECT and analyzed the profiles of their subtests. Atypical benign partial epilepsy of childhood (ABPE) is a type of BCECT in which patients have minor generalized seizures and their EEGs show continuous spike-waves during sleep. We also performed the same tests in five patients with ABPE, and compared the results in the two groups.
Neuropsychological tests performed are as follows: Kaufman assessment battery for children (K-ABC), Wechsler intelligence scales for children-revised (WISC-R), Illinois test of psycholinguistic abilities (ITPA), Benton visual retention test (BVRT), Token test, calculation, figure copying task, letter copying task, line bisection task, and line cancellation task.
Mental processing composite of the K-ABC and FIQ of the WISC-R were within normal limits in all children with BCECT and ABPE, but were generally lower in ABPE than in BCECT. On the other hand, the profiles of subtests of ITPA in children with BCECT revealed the significant feature of the lower scores on verbal expression (p=0.013) and auditory sequential memory (p= 0.035). Considering the normal scores in the elementary cognitive functions, such as visual and verbal functions and long-term memory, disturbance in the process of executive functions such as flexibility, fluency, and working memory could cause this characteristic profile.
ABPE also showed the similar profile in the subtests of ITPA to that of BCECT. It is likely that both groups of children share the common cognitive dysfunction.

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In order to objectively evaluate visual perception of patients with mental retardation (MR), the P300 eventrelated potentials (ERPs) for visual oddball tasks were recorded in 26 patients and 13 age-matched healthy volunteers. The latency and amplitude of visual P300 in response to the Japanese ideogram stimuli (a pair of familiar Kanji characters or unfamiliar Kanji characters) and a pair of meaningless complicated figures were measured. In almost all MR patients visual P300 was observed, however, the peak latency was significantly prolonged compared to control subjects. There was no significant difference of P300 latency among the three tasks. The distribution pattern of P300 in MR patients was different from that in the controls and the amplitudes in the frontal region was larger in MR patients. The latency decreased with age even in both groups. The developmental change of P300 latency corresponded to developmental age rather than the chronological age. These findingsuggest that MR patients have impairment in processing of visual perception. Assessment of P300 latencies to the visual stimuli may be useful as an objective indicator of mental deficit.

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Paroxysmal kinesigenic choreoathetosis (PKC) is a rare and benign disorder with its onset in childhood. PKCgenerally improves with age, and its pathophysiology has not been revealed.
We recorded both ictal and interictal SPECT in a 14-year-old girl with PKC. Ictal SPECT showed a significantdecrease in blood flow in the caudate nucleus contralateral to the limb showing an involuntary movement.
We also examined paired-pulse stimuli somatosensory evoked potential (SEP) of the same patient. Recoverypattern of P25 and N33 components was normal and comparable to 5 healthy volunteers, suggesting the absence ofcortical hyperexcitability.
These results suggest dysfunction or immaturity of the indirect pathway of basal ganglia in PKC, as well asthehyperexcitability of the descending pathway.

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Development of MRI enabled accurate and rapid diagnosis of head traumas which had been impossible with the conventional CT. The diagnosis of posttraumatic diffuse axonal injury (DAI) is a typical example. Most of the reported cases of DAI in childhood are of relatively older age, and DAI is rare in infancy. We report here a 1-year-9-month-old infant with DAI. After falling from two meters in height, he presented consciousness disturbance and a seizure that necessitated artificial respiration for half a day. He recovered completely without sequelae. Brain CT on arrival to the ER department was unremarkable, but MRI scans shortly thereafter showed typical findings of DAI.
In childhood, DAI rends to be milder than in adult-hood, which may be explained by the age-dependent frequency of traffic accidents, and by anatomical and functional factors of a infant's brain. A large number of infantile cases should be accumulated to draw a more clearcut conclusion.

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A boy aged 4 years and 2 months died of an unknown neurological disease, which had insidiously occurred around the age of one year. The case slowly developed sleeping tendency, spastic tetraplegia, optic nerve atrophy and flexion contracture but no epileptic seizures. There was neither consanguinity nor familial history of neurological disorders. The proband had intrauterine exposure to X-ray at the seventh fetal month. Laboratory examinations including antiviral antibodies and lysosomal enzymes provided no evidence for known brain disorders.
Neuropathological examination revealed widespread multicystic destruction predominantly in the centrum semiovale. The subcortical arcuate fibers were spared. The commissural fibers as well as long tract fibers were also symmetrically affected. There was neither inflammatory reaction, calcification, Rosenthal fibers nor globoid cells. Axons were comparatively preserved. Tissue debris was not metachromatic in acid cresyl violet stain. Chemical analysis demonstrated no changes in fatty acid profiles.
These clinicopathological features partly mimic leukoencephalopathy with vanishing white matter (van der Knaap), except for the lack of familial history and cerebellar signs, and the more extensive neuropathological lesions. Although the influence of intrauterine X-ray irradiation could not be neglected completely, reports of several similar cases in the literature suggests that this case had a new variant of child-onset multicystic leukoencephalopathy or leukodystrophy.

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We report a case of severe rhabdomyolysis associated with Salmonella encephalopathy. A 3-year-old girl was admitted to our hospital because of status convulsives and unconsciousness. She was diagnosed as having Salmonella encephalopathy with rhabdmyolysis, and was treated by mild hypothermia and mechanical ventilation. Five days later she developed anuria with increased serum levels of myoglobin, CK and creatinine. And the diagnosis of acute renal failure was made. Peritoneal dialysis was begun from 6 days after admission. Hyperinfusion, the usual therapy of rhabdomyolysis, was not performed. She survived showing gradual improvement of renal function and consciousness. In a case of rhabdomyolysis complicating a neurologic disorder, a well-known poor prognostic factor, priority should be given to brain protection rather than to symptomatic treatment of rhabdomyolysis.

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We report a 9-year-old boy with occipital lobe epilepsy who showed a prolonged QTc on the ictal electrocardiogram (ECG). He complained of sudden onset of blindness accompanied with vomiting and headache. Since ECG revealed a prolonged QTc, he was transferred to our pediatric emergency center. Occipital spike and slow wave complexes on the electroencephalogram (EEG) suggested the diagnosis of occipital lobe epilepsy. Administration of carbamazepine (190 mg) resulted in the disappearance of the blindness and abnormal waves on EEG. This is the first report to describe the occurrence of prolonged QTc during seizures of occipital lobe epilepsy. Because of the high risk of life-threatening ventricular arrhythmia induced by prolongation of QTc such as torsades de pointes, attention should be paid to the ECG findings in patients with occipital lobe epilepsy.

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A 14-year-old boy born at 39 gestational weeks with the birth weight of 3, 250 g, had severe mental retardation and spastic quadriplegia of unknown etiology from early childhood. At 7 years of age, disturbance of night sleep appeared with several awakenings. Combined treatment with melatonin (MLT; 0.04 mg/kg) and flunitrazepam (FNZ; 0.025 mg/kg) was more effective than monotherapy with FNZ for the sleep disturbance.
Difference of the effects of the combined therapy and the monotherapy for the sleep disturbance were assessed by polysomnographies (PSGs), consisted of EEG (C3, C4), bipolar EOG and surface EMG on the mentalis muscle.
The PSGs were performed twice at 13 years 6 months old, and at 14 years 1 month old. In both trials, the number of awakening was fewer, total sleep time was longer, percent (%) stage I and II were lower and %REM sleep was larger in combined MLT and FNZ therapy than in FNZ monotherapy.
The present study suggests that the combined MLT and FNZ therapy not only reduces awakening during sleep but also normalizes sleep architecture. This therapy is valuable because normalization of sleep is important for the developing brain as it reflects the normal functioning of the aminergic neurons of the midbrain and the brainstem which have important roles for morphological and functional development of the brain in immature brain.

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We reported the MRI findings and clinical course of two patients with ophthalmoplegic migraine. Both patients presented with unilateral oculomotor nerve palsy. Contrast enhanced MR imaging revealed unilateral enhancement and thickening of the oculomotor nerve in one patient.
Prednisolone was effective in both patients, but only could transiently. On the other hand, cyproheptadine hydrochloride could completely prevent recurrent attacks of ophthalmoplegic migraine. Thus, MR imaging with of contrast enhancement is useful in the diagnosis of ophthalmoplegic migraine. Cyproheptadine hydrochloride is better than prednisolone to prevention recurrent attacks and to avoid adverse effects.

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A silicone stent (Dumon stent) was used in a severe motor and intellectual disability with severe tracheal stenosis due to granulation caused by an implanted the expanded metal stent (Ultraflex Nitinol Stent). To treat tracheobronchial malacia, diagnosed in infancy, expanded metalic stent was implanted at the ages of 30 and 32 years. However, a few months after the second implantation, progressive dyspnea apperared, and he had to use a respirator under intravenous anesthesia. Bronchoscopy showed re-stenosis of the trachea due to a granulation tissue within the stent. A Dumon stent was applied to control the re-stenosis. He was successfully weaned from a respirator. Since granulation tissue had recurred at the end of the Dumon stent after 3 months, a long term care of the airway and regular observation is necessary after implantation of stents.

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[in Japanese]

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