Biomedical subjects

Chisako Fukuda

Publications and source records attributed to Chisako Fukuda.

6 recordsLinked to original sources

PubMed2006

Disappearance of frontal N30 component of median nerve stimulated SSEPs in two young children with abnormal striatal lesions.

Median nerve stimulated short-latency somatosensory evoked potentials (MN-SSEPs) were performed in two young children with extrapyramidal symptoms. Brain MRI showed bilaterally symmetric striatal lesions in both cases. The subcortical components (N9, N11, N13, N18, P11, and P13) and the parietal component (N20) were normally detected, whereas the frontal component (N30) was not detected bilaterally in either case. In conclusion, our findings suggest that frontal N30 disappearance could be observed since as early as young childhood and it may pathophysiologically reflect severe dysfunction in the extrapyramidal system.

Brain Injuries↗

PubMed2006

Lower brainstem dysfunction in an infant with persistent primitive trigeminal artery.

A 6-month-old boy with persistent primitive trigeminal artery (PPTA) presented with stridor, dysphagia, delayed motor development and postural neck and shoulder dystonia. Magnetic resonance imaging/angiography and ultrasonography revealed PPTA, with flow from the dilated basilar artery to the right internal carotid artery, lower brainstem compression by the dilated basilar artery, and cerebellar vermis hypoplasia. Evoked potentials showed lower pons and medulla oblongata functional disruption. These lesions may be related to vascular etiology in the lower brainstem or to congenital malformation syndrome involving infratentorial structures. The relationship of this condition to Möbius syndrome is discussed.

Abnormalities, Multiple↗

PubMed2006

Topographic MN-SSEPs (N18, N20 and N30) might characterize underlying CNS involvements in representative types of cerebral palsy.

This study is aimed at constructing the neurophysiological basis for determining the characteristic features of cerebral motor disturbance in representative cerebral palsy (CP) types using topographical S-SEPs technology. Median-nerve stimulated S-SEPs (MN-SSEPs) were examined for 23 patients with four representative types of cerebral palsy: 6 athetotic (including 3 patients due to hypoxic-ischemic encephalopathy (HIE) and 3 to kernicterus), 7 hemiplegic, 5 diplegic and 5 tetraplegic types, and 13 normal controls. In HIE group of athetotic CP, frontal N30 specifically showed severe amplitude reduction or abolishment. In hemiplegic CP, both N20 and N30 on the affected cerebral side tended either to disappear or to be normally evoked at the same time, and their mean amplitudes declined severely. In diplegic CP, the amplitudes of subcortical N18 and parietal N20 were not small but significantly enlarged. N30 amplitude stayed within normal. The reason for this unexpected enlargement of N18 and N20 is unclear, but may be partly due to premature birth which caused abnormally abundant dendritic spine due to absence from perinatal normal spine elimination in the brainstem. In several quadriplegic patients, both N20 and N30 disappeared. The mean amplitude of N30 severely decreased. In conclusion, topographical results of N18, N20 and N30 may basically suggest the underlying involvement of nervous structures in CP according to their representative type.

Adolescent↗

PubMed2003

Re-evaluation of short latency somatosensory evoked potentials (P13, P14 and N18) for brainstem function in children who once suffered from deep coma.

One of the major clinical features of brain death is deep coma. Therefore, we re-evaluated retrospectively electrophysiological examinations of brainstem function in about 31 children who had once suffered from deep coma in order to reveal its pathophysiological characteristics. The patient age at coma ranged from 1 month to 10 years (mean 2 years 1 month). The electrophysiological examinations were performed, including any of short-latency somatosensory evoked potential (SSEP), brainstem auditory evoked potential (BAEP) and blink reflexes. We first compared results between the fair and poor prognostic groups, and then re-evaluated SSEP results on a few severely impaired patients with persistent vegetative state (PVS). Subsequently, SSEP clarified more specific findings for a deep coma condition than BAEP and blink reflex. A lack of P14, N18 and N20, and an amplitude reduction or vagueness of P13 in SSEP in these children strongly suggested high risk in their future neurological prognosis. In conclusion, electrophysiological examinations, especially SSEP (P13, P14 and N18), might be very useful in obtaining a long-term neurological prognosis after deep coma in children.

Blinking↗

PubMed2002

Congenital mirror movement: a study of functional MRI and transcranial magnetic stimulation.

Two male patients (a child and an adult) with congenital mirror movement were studied using functional MRI (fMRI) and transcranial magnetic stimulation (TMS). Bilateral primary sensorimotor cortices were activated during unilateral hand gripping on fMRI when the child patient was 8 years old andthe adult was 37 years old. Bilateral motor evoked potentials were induced from the hand and forearm muscles after TMS of each hemisphere. Bilateral motor responses were also induced from the arm muscles in the adult patient. Bilateral motor responses had short and similar latencies. Contralateral motor responses to TMS were smaller than ipsilateral ones in the hand muscles, while contralateral responses were larger than ipsilateral ones in the arm muscles. Contralateral hand motor responses reduced in amplitude or disappeared with increasing age while in the child patient, mirror movements decreased gradually. Our results suggest that bilateral activation of the primary sensorimotor cortices during intended unilateral hand movement and bilateral motor responses to TMS account, at least in part, for the pathophysiology of congenital mirror movement. Reduction of contralateral hand motor responses may be related to the decrease in mirror movements during development.

Adult↗

PubMed2002

[P22 and N30 of median nerve SSEPs--independence of the frontal waves from parietal waves].

Median nerve short-latency somatosensory evoked potentials (MN-SSEPs) were recorded from the scalp to assess frontal lobe functions in children. Forty-nine patients, aged between three and fifty years old underwent 87 examinations. They were divided into four groups: A (3 to 4 years old); B (5 to 6 years old); C (7 to 15 years old) and D (20 to 50 years old). Stimulus electrodes were placed near the wrist on the median nerve. The study was done mostly in the waking state. To evaluate the independence of the frontal lobe from the parietal lobe we correlated the frontal P22 and parietal N20, and compared the frontal N30 with parietal negative waves. The intervals of the peak latency differed between P22 and N20 by -1.5 to 1.5 msec. Significant differences were noted between groups A and D, and between C and D. N30 and negative parietal waves resembled each other in children 3 to 4 years of age, but became different from 5 years old. They were dissimilar after 6 years old. Therefore, N30 waves were useful for evaluating the frontal elements in children over 5 years of age.

Adolescent↗