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Azusa Shimizu, Yuzo Komuro, Masakazu Miyajima and Hajime Arai

An otherwise healthy, developmentally normal 3-week-old male infant presented with complex multisuture craniosynostosis involving the metopic suture and bilateral coronal sutures with frontal prominence and hypotelorism. Frontal craniectomy and bilateral frontoorbital advancement remodeling were performed at the age of 5 months. The postoperative course was uneventful. The child's development was normal up to 8 months after the operation. His father and grandfather had similar specific deformities of the cranium, but no anomaly of the extremities was found, and conversation suggested that their intelligence was normal, excluding the possibility of syndromic craniosynostosis. A DNA analysis revealed large-scale copy number polymorphism of chromosome 4 in the patient and his family, which may include the phenotype of the cranium. Neither FGFR mutation nor absence of a TWIST1 mutation in the sequence from 291 to 1087, which includes DNA binding, Helix1, Loop, and Helix2, was identified. The patient apparently had a rare case of familial nonsyndromic craniosynostosis. The authors plan further genomic analysis of this family and long-term observation of the craniofacial deformity of this patient.

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Hajime Arai, Kiyoshi Sato and Akira Yanai

✓ Eight patients underwent hemihypoglossal—facial nerve anastomosis (anastomosis of a split hypoglossal nerve to the facial nerve) for treatment of unilateral facial palsy. All patients previously had undergone resection of a large acoustic neurinoma and the facial nerve had been resected at that time. The interval between tumor resection and hemihypoglossal—facial nerve anastomosis ranged from 1 to 6 months, with an average of 2.1 months. Postoperative recovery of facial movement was good in all cases during an average follow-up period of 4.2 years. In all eight patients, the degree of hypoglossal nerve atrophy on the operated side was graded mild or moderate, but not severe. It was concluded that hemihypoglossal—facial nerve anastomosis results in good facial reanimation as long as the procedure is performed early after the onset of facial palsy and that this procedure may reduce the degree of hemiglossal atrophy in comparison with classic hypoglossal—facial nerve anastomosis.

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Masakazu Miyajima, Hajime Arai, Osamu Okuda, Makoto Hishii, Hajime Nakanishi and Kiyoshi Sato

Object. In this study the authors identify and investigate two new classifications of suprasellar arachnoid cysts.

Methods. The authors used computerized tomography cisternography, magnetic resonance (MR) imaging, and neuroendoscopy to investigate nine cases of suprasellar arachnoid cysts. A communicating cyst with early filling and early clearance of a radioopaque tracer was found in seven of nine cases; a communicating cyst with delayed filling and delayed clearance of the tracer was observed in one case; and a noncommunicating cyst was observed in the other. The MR findings indicated a variation in the position of the basilar artery (BA) bifurcation in relation to the ventral surface of the midbrain. A distance existed between the BA bifurcation and the ventral surface of the midbrain in a communicating cyst with early filling, whereas the BA bifurcation was posteriorly displaced in a communicating cyst with delayed filling and also in a noncommunicating cyst, leaving little space between the bifurcation and the ventral surface of the midbrain. Endoscopic observation revealed, in the case of communicating cysts with early filling and early clearance of tracer, that the BA bifurcation is located inside the cyst with no overlying membrane, whereas in a noncommunicating cyst, the BA and its branches can be observed through the transparent membrane of the lesion.

Conclusions. The authors postulate two different types of suprasellar arachnoid cysts: a noncommunicating intraarachnoid cyst of the diencephalic membrane of Liliequist and a communicating cyst that is a cystic dilation of the interpeduncular cistern.

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Xi Qing Shen, Masakazu Miyajima, Ikuko Ogino and Hajime Arai

Object

Aquaporin (AQP) water channels play an important role in water movement in the central nervous system. The authors used an animal model to examine the relationship between AQP4 expression and spontaneously arrested hydrocephalus.

Methods

Congenitally hydrocephalic H-Tx (hH-Tx) rats and nonhydrocephalic H-Tx (nH-Tx) rats were used in the study. Brain tissue sections were obtained from animals in both groups at 1 day, 1 week, 4 weeks, and 8 weeks of age. Sections were immunostained using AQP4 antibodies, and AQP4 expression was assessed.

In the nH-Tx group, no AQP4 expression was seen in 1-day-old rats, and AQP4 expression was found in astrocytes around capillaries of the cerebral cortex and in ependymal cells lining the ventricles in 1-week-old rats. In the 4- and 8-week-old nH-Tx animals, AQP4 expression was seen in subpial zones of the cortex, on foot processes of pericapillary astrocytes, and in periventricular regions. A marked increase in cerebral cortical expression of AQP4 was observed at 8 weeks in the hH-Tx rats but not in the nH-Tx rats.

Conclusions

The authors hypothesize that the differences in cerebral AQP4 expression in the 1-day-old and 1-week-old nH-Tx rats compared with the 4- and 8-week-old nH-Tx rats may be related to the fact that the cerebrospinal fluid (CSF) circulation of newborns and infants differs from that of adults. It is also possible that the increased expression of AQP4 seen in the 8-week-old hH-Tx animals was related to the development of alternative pathways of CSF circulation, which also may occur in instances of spontaneously arrested hydrocephalus.

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Yasuomi Nonaka, Masakazu Miyajima, Ikuko Ogino, Madoka Nakajima and Hajime Arai

Object

Some cases of compensatory hydrocephalus have been reported in which cognitive deficiency progresses despite the absence of progressive ventricular dilation. In this study, the differentially expressed genes in compensated hydrocephalic H-Tx rat cortices were determined. A molecular mechanism that induces neuronal death in the cerebral cortex of compensated hydrocephalus is proposed.

Methods

The cerebral cortices of 8-week-old H-Tx rats with spontaneously arrested hydrocephalus (hH-Tx) and nonhydrocephalic H-Tx (nH-Tx) control rats were subjected to cDNA microarray analysis followed by canonical pathway analysis.

Results

In the hH-Tx rats, many genes in the amyloidal processing pathway showed altered expression, including Akt3 and p38 MAPK. These latter genes are involved in tau protein phosphorylation, and their increased expression in hydrocephalus was confirmed by real-time polymerase chain reaction analysis. Immunohistological and immunoblot analysis revealed elevated phosphorylated tau expression in the cerebral cortex neurons of the hH-Tx rats.

Conclusions

The accumulation of phosphorylated tau protein in the cerebral cortex may be one of the mechanisms by which later cognitive dysfunction develops in patients with compensated hydrocephalus. More work needs to be done to determine if the accumulation of phosphorylated tau in the cortex can help predict which patients may decompensate thus requiring more aggressive treatment for compensated hydrocephalus.

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Madoka Nakajima, Kuniaki Bando, Masakazu Miyajima and Hajime Arai

The authors have developed a minimally invasive lumboperitoneal shunt placement procedure conducted after administration of a local anesthetic. The procedure involves placing a guide wire and a peel-away sheath under fluoroscopic and CT guidance. Between June 2004 and August 2006, 40 patients (21 men and 19 women; mean age 72.5 years [range 33–86 years]) underwent surgery. A Codman Hakim programmable valve system (82–3844, Codman & Shurtleff, Inc.) was used for the procedure. The mean operating time was 53 minutes, and 7 patients (17.5%) developed shunt dysfunction complications. These complications comprised an infected shunt valve in 2 patients, postoperative lower-limb pain in 1 patient, and shunt obstruction (caused by debris and hemorrhage) at the ventral and lumbar ends in 2 patients each. This procedure is less invasive than conventional lumboperitoneal shunt insertion and could be performed as an outpatient surgery for treatment of idiopathic normal-pressure hydrocephalus.

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Ayato Hayashi, Masanobu Nishida, Hisakazu Seno, Masahiro Inoue, Hiroshi Iwata, Tomohiro Shirasawa, Hajime Arai, Ryoji Kayamori, Yuzo Komuro and Akira Yanai

Object

The authors have developed a technique for the treatment of facial paralysis that utilizes anastomosis of the split hypoglossal and facial nerve. Here, they document improvements in the procedure and experimental evidence supporting the approach.

Methods

They analyzed outcomes in 36 patients who underwent the procedure, all of whom had suffered from facial paralysis following the removal of large vestibular schwannomas. The average period of paralysis was 6.2 months. The authors used 5 different variations of a procedure for selecting the split nerve, including evaluation of the split nerve using recordings of evoked potentials in the tongue.

Results

Successful facial reanimation was achieved in 16 of 17 patients using the cephalad side of the split hypoglossal nerve and in 15 of 15 patients using the caudal side. The single unsuccessful case using the cephalad side of the split nerve resulted from severe infection of the cheek. Procedures using the ansa cervicalis branch yielded poor success rates (2 of 4 cases).

Some tongue atrophy was observed in all variants of the procedure, with 17 cases of minimal atrophy and 14 cases of moderate atrophy. No procedure led to severe atrophy causing functional deficits of the tongue.

Conclusions

The split hypoglossal-facial nerve anastomosis procedure consistently leads to good facial reanimation, and the use of either half of the split hypoglossal nerve results in facial reanimation and moderate tongue atrophy.

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Shizuo Oi, Sadahiro Nomura, Masato Nagasaka, Hajime Arai, Reizo Shirane, Yasuo Yamanouchi, Hiroshi Nishimoto and Hiroaki Date

Object

The natural history of asymptomatic spinal lipoma in infancy remains unclear, and the indication for the prophylactic untethering operation is still debatable. To address this question, a multicenter cooperative study for the treatment of spinal lipoma was performed by the 7 most active institutions in neurosurgical care for spina bifida in Japan between 2001 and 2005.

Methods

Patients were classified using the embryopathogenetic surgicoanatomical classification. Their neurosurgical postoperative course was analyzed using the Spina Bifida Neurological Scale. Among 261 patients, 159 were asymptomatic and 102 were symptomatic.

Results

Of the 136 patients for whom prophylactic surgeries were performed, 135 remained asymptomatic and only 1 (0.4%) of the 261 patients presented with mild sensory disturbance. Mild foot deformity was identified in 1 (4.3%) of 23 conservatively observed patients. Of 100 symptomatic patients, deterioration after surgery was seen in 6%, and improvement in 44%. Complete resolution of symptoms was seen in only 14.2%. Filar types for patients > 3 years old improved in Spina Bifida Neurological Scale scores from 12.3 to 14.0. The mean age of symptomatic patients with lipomyelomeningocele was the youngest of all (1.3 years), which indicates lipomyelomeningocele may deteriorate in early infancy. Improvements from surgery were seen for all types of lipoma except the caudal type, presenting at an older mean age (15 years).

Conclusions

A low rate of postsurgical worsening indicates that surgeries for asymptomatic and symptomatic lipomas are safe. Surgeries done after the onset of symptoms seldom cure the patients. These two results support early untethering for any kind of lipoma; however, further study of the natural history is required.

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Madoka Nakajima, Hidenori Sugano, Yasushi Iimura, Takuma Higo, Hajime Nakanishi, Kazuaki Shimoji, Kostadin Karagiozov, Masakazu Miyajima and Hajime Arai

A girl aged 2 years 10 months suddenly went into a deep coma and demonstrated left hemiplegia. At birth, she had exhibited a left-sided facial port-wine stain typical of Sturge-Weber syndrome (SWS) and involving the V1 and V2 distributions of the trigeminal nerve. Computed tomography showed a right thalamic hemorrhage with acute hydrocephalus. Magnetic resonance imaging with Gd enhancement 8 months before the hemorrhage had shown a patent superior sagittal sinus (SSS) and deep venous system. Magnetic resonance imaging and MR angiography studies 2 months before the hemorrhage had revealed obstruction of the SSS and right internal cerebral vein (ICV). Given that a digital subtraction angiography study obtained after the hemorrhage did not show the SSS or right ICV, the authors assumed that impaired drainage was present in the deep venous system at that stage. The authors speculated that the patient's venous drainage pattern underwent compensatory changes because of the occluded SSS and deep venous collectors, shifting outflow through other cortical venous channels to nonoccluded dural sinuses. Sudden congestion (nearly total to total obstruction) of the ICV may have caused the thalamic hemorrhage in this case, which is the first reported instance of pediatric SWS with intracerebral hemorrhage and no other vascular lesion. Findings suggested that the appearance of major venous sinus occlusion in a child with SWS could be a warning sign of hemorrhage.