Search Results

You are looking at 1 - 7 of 7 items for

  • Author or Editor: Kenichi Nishiyama x
Clear All Modify Search
Restricted access

Kenichi Nishiyama, Hiroshi Mori and Ryuichi Tanaka

Object. The aim of this study was to analyze physiological changes in cerebrospinal fluid (CSF) dynamics following endoscopic third ventriculostomy (ETV) for shunt-dependent noncommunicating hydrocephalus.

Methods. Clinical data obtained in 15 patients treated with ETV for shunt malfunction were analyzed. Magnetic resonance imaging studies demonstrated the obstruction of the ventricular system preoperatively. After ETV, the existing shunt system was removed and a continuous extraventricular drain, set at 30 cm H2O in height, was installed to measure daily amounts of CSF outflow. Cerebrospinal fluid dynamics after ETV were also evaluated using 111In-diethylenetriamine pentaacetic acid radioisotope cisternography in six of 15 patients within 1 month of the procedure. Three patients underwent cisternography at 6 months after ETV. Cisternograms were obtained at 1, 5, 24, and 48 hours after injection of the radioisotope. To study CSF absorptive capacity, ratios of radioisotope counts at 48 and 5 hours after injection were calculated (C48:C5). Seven of 15 patients had daily outflows of CSF of less than 20 ml; this volume decreased quickly within a few days. The other eight patients demonstrated an outflow of more than 150 ml of CSF for several days, three of whom had signs of transiently increased intracranial pressure. Their CSF outflow volume decreased gradually and symptoms improved within 1 week. Ratios of C48:C5 were within normal limits in five of six patients who had undergone cisternography 1 month after ETV. These ratios were decreased in all three patients who had undergone cisternography at 6 months after ETV compared with that measured at 1 month after the procedure.

Conclusions. Our data suggest that CSF dynamics convert from a shunt-dependent state to a shunt-independent state within 1 week following ETV in patients with shunt-dependent noncommunicating hydrocephalus. Nonetheless, intraventricular pressure does not decrease quickly in certain cases. Cerebrospinal fluid absorptive capacity or CSF circulation through the subarachnoid space may show further improvement several months after ETV.

Free access

Atsuko Harada, Kenichi Nishiyama, Junichi Yoshimura, Masakazu Sano and Yukihiko Fujii

Object

Sacrococcygeal dimples in the gluteal fold, also known as coccygeal pits, are observed in 2%–4% of newborns. Sacrococcygeal dimples are not generally considered to be associated with a significant risk of intraspinal anomalies and therefore are not thought to require further radiographic evaluation. Accordingly, the precise incidence and nature of intraspinal lesions that may be associated with sacrococcygeal dimples is unclear. This study was conducted to determine the incidence of intraspinal lesions in patients with intergluteal dimples.

Methods

In this study, the authors used MRI to evaluate 103 children who were seen at the Niigata University Medical and Dental Hospital between 2006 and 2011 because of skin abnormalities in the lumbosacral region. Of these children, 14 were excluded as having a subcutaneous fatty mass, and 5 were excluded because the dimples were above the gluteal fold or did not end at the coccyx. The remaining 84 patients were classified according to whether the bottom of the dimple was visible (shallow) or not (deep). The authors also retrospectively examined other skin abnormalities and coexisting anomalies.

Results

The mean age at the time of MRI evaluation was 11.7 months. Magnetic resonance imaging led to the identification of fibrolipoma of the terminal filum (FTF) in 14 cases (16.7%); 6 of these patients also had a low conus. Classified by depth, there were 58 cases with shallow and 26 with deep dimples. Fibrolipoma of the terminal filum was found in significantly more patients with deep dimples (9 [34.6%]) than in those with shallow dimples (5 [8.6%]). The frequency of other congenital anomalies was significantly higher in patients with FTF-associated dimples (6 [42.9%] of 14) than in those with dimples that were not associated with FTF (9 [12.9%] of 70).

Conclusions

Fibrolipoma of the terminal filum was identified by MRI in 16.7% of patients with sacrococcygeal dimples. The risk of FTF increased when the dimples were deeply excavated or were accompanied by congenital anomalies. Magnetic resonance imaging should be performed to identify intraspinal lesions when there are high risk factors for intraspinal abnormalities, or when an ultrasound screening suggests intraspinal abnormalities.

Restricted access

Hiroshi Mori, Toshiro Koike, Tsuyoshi Fujimoto, Kenichi Nishiyama, Junichi Yoshimura and Ryuichi Tanaka

✓ Nontumoral bilateral occlusion of the Monro foramina is a rare clinical condition. Treatment includes shunt placement, endoscopic procedures, or both. The authors describe the case of a 22-year-old woman who had previously undergone placement of a ventriculoperitoneal shunt via a right frontal approach for management of triventricular dilation due to aqueductal stenosis. Six years postoperatively she presented with right-sided slit-ventricle syndrome and stenosis of the right Monro foramen, which was treated with an endoscopic third ventriculostomy and fenestration of the septum pellucidum. Two years later she presented with bilateral lateral ventricular dilation. Inspection of the right lateral ventricle with a fiberscope revealed occlusion of the septum pellucidum fenestration; on observation, the right Monro foramen was covered by thick, tough granulation tissue and the left was occluded by thin membranous tissue. Repeated fenestration of the septum pellucidum and left Monro foraminoplasty were therefore performed by perforating this thin tissue. A stent was then introduced into the third ventricle via the right lateral ventricle, the fenestration in the septum pellucidum, and the left Monro foramen.

The authors note that fiberscopes are in general more maneuverable than rigid endoscopes and conclude that they are particularly useful for the treatment of this type of hydrocephalus.

Full access

Satoko Kojima, Junichi Yoshimura, Tetsuro Takao, Tetsuro Tamura, Kenichi Nishiyama, Shigeru Maruyama, Masashi Suda and Yukihiko Fujii

The authors report the case of a mobile spinal enterogenous cyst in a 2-year-old boy, who was admitted to the hospital several times for intermittent paraplegia. Magnetic resonance imaging and CT revealed an isolated cyst in the lumbar spinal canal. The symptoms were caused by transient myelopathy of the conus medullaris and radiculopathy of the cauda equina due to the changing size and location of the cyst. The cyst was surgically extirpated, after which the symptoms resolved. The histopathological diagnosis was enterogenous cyst. The clinical history of intraspinal enterogenous cyst is usually progressive. Mobility and changes in size are rare pathophysiological findings. The authors speculate that the cyst wall did not adhere to the surrounding structures and had ruptured and quickly reformed. Enterogenous cyst should be considered in the differential diagnosis of spinal intradural cysts in children with radiculomyelopathy.

Restricted access

Shinya Jinguji, Junichi Yoshimura, Kenichi Nishiyama, Hiroshi Aoki, Keisuke Nagasaki, Manabu Natsumeda, Yuichiro Yoneoka, Masafumi Fukuda and Yukihiko Fujii

Object

Radiation monotherapy—prophylactic craniospinal or whole-brain irradiation paired with a radiation boost to the primary tumor—is the standard treatment for intracranial germinomas at the authors' institution. The authors assessed long-term outcomes of patients with germinoma who underwent therapy and identified factors affecting them.

Methods

The authors retrospectively analyzed data obtained in 46 patients (35 males and 11 females, age 5–43 years at diagnosis) who had been treated for intracranial germinomas between 1990 and 2009 at the authors' institution. Thirty patients had germinomas in localized regions and 16 in multiple regions. Thirty-eight patients (83%) underwent radiotherapy alone (craniospinal irradiation in 32 and whole-brain irradiation in 6). Seven patients underwent radiochemotherapy and 1 underwent chemotherapy alone. The mean radiation doses for the whole brain, spine, and primary tumor site were 26.9, 26.6, and 49.8 Gy, respectively. The median follow-up period was 125 months.

Results

The 10-year overall and recurrence-free survival rates were 93.3% and 89.3%, respectively. None of the 38 patients who received radiation monotherapy developed a recurrent lesion, whereas 1 of 7 who underwent radiochemotherapy and the 1 patient who underwent chemotherapy had a recurrent lesion. Of the entire population, 26 patients required hormone replacement therapy, 2 had short stature, and 1 developed a radiation-induced meningioma. Seventeen of the 25 childhood- or adolescent-onset patients were 19 years or older at the latest follow-up visit, 15 of whom graduated from senior high school, and only 2 of whom graduated from college. Of 34 patients who were 19 years or older at the latest visit, 4 were students, 18 worked independently, 4 worked in sheltered workplaces, and 8 were unemployed. Of the 34 patients, 4 got married after the initial treatment, 3 of whom had children. There were 8 patients (17%) with low postoperative Karnofsky Performance Scale (KPS) scores that were significantly associated with impaired neurocognitive functions, severe surgical complications, and neurological impairments. In 10 of the 46 patients, KPS scores at the latest visit were lower than their postoperative KPS scores. These decreases in KPS scores were significantly correlated with a delayed decline in neurocognitive functions in childhood-onset patients and a postoperative impairment of neurocognitive functions in patients with adolescent- or adult-onset germinoma.

Conclusions

No tumor recurrence occurred in germinoma patients treated with the authors' radiation monotherapy, which appears to be effective enough to cure the tumor. Brain damage caused by tumors themselves and surgical complications were found to adversely affect functional outcomes in patients regardless of their age. Although radiotherapy rarely caused late adverse effects in patients with adolescent- or adult-onset, in some childhood-onset lesions, the radiation seems to carry the risk of neurocognitive dysfunctions, which are attributable to late adverse effects. Accordingly, treatments for germinoma patients should be selected according to a patient's age and the extent of the tumor and with particular care to avoid surgical complications.

Free access

Hiroshi Kageyama, Masakazu Miyajima, Ikuko Ogino, Madoka Nakajima, Kazuaki Shimoji, Ryoko Fukai, Noriko Miyake, Kenichi Nishiyama, Naomichi Matsumoto and Hajime Arai

OBJECT

The authors’ goal in this paper is to provide the first clinical, radiological, and genetic studies of panventriculomegaly (PaVM) defined by a wide foramen of Magendie and large cisterna magna.

METHODS

Clinical and brain imaging data from 28 PaVM patients (including 10 patients from 5 families) were retrospectively studied. Five children were included. In adult patients, the age at onset was 56.0 ± 16.7 years. Tetraventricular dilation, aqueductal opening with flow void on T2-weighted images, and a wide foramen of Magendie and large cisterna magna (wide cerebrospinal fluid space at the fourth ventricle outlet) were essential MRI findings for PaVM diagnosis. 3D fast asymmetrical spin echo sequences were used for visualization of cistern membranes. Time-spatial labeling inversion pulse examination was performed to analyze cerebrospinal fluid movement. Copy number variations were determined using high-resolution microarray and were validated by quantitative polymerase chain reaction with breakpoint sequencing.

RESULTS

Adult patients showed gait disturbance, urinary dysfunction, and cognitive dysfunction. Five infant patients exhibited macrocranium. Patients were divided into 2 subcategories, those with or without downward bulging third ventricular floors and membranous structures in the prepontine cistern. Patients with bulging floors were successfully treated with endoscopic third ventriculostomy. Genetic analysis revealed a deletion in DNAH14 that encodes a dynein heavy chain protein associated with motile cilia function, and which co-segregated with patients in a family without a downward bulging third ventricular floor.

CONCLUSIONS

Panventriculomegaly with a wide foramen of Magendie and a large cisterna magna may belong to a subtype of congenital hydrocephalus with familial accumulation, younger age at onset, and symptoms of normal pressure hydrocephalus. In addition, a family with PaVM has a gene mutation associated with dysfunction of motile cilia.

Restricted access

Nakamasa Hayashi, Hisayuki Murai, Shoichiro Ishihara, Takayuki Kitamura, Tamotsu Miki, Tomoru Miwa, Masakazu Miyajima, Kenichi Nishiyama, Takayuki Ohira, Shigeki Ono, Tomonari Suzuki, Shingo Takano, Isao Date, Naokatsu Saeki and Shunro Endo

Object

The authors report their investigation on the current status of neuroendoscopic biopsy for ventricular and paraventricular tumors as well as treatment for associated hydrocephalus in Japan.

Methods

Patients who had undergone therapeutic neuroendoscopy between 2005 and 2009 were included in this study. The main items examined were age; sex; localization of tumor; pathological diagnosis using biopsy; the presence, treatment, and efficacy of treatment of associated hydrocephalus; perioperative complications; activities of daily living (ADL) before and after therapeutic neuroendoscopy; and the presence of dissemination during the postoperative course.

Results

Seven hundred fourteen patients from 123 sites (462 male and 252 female patients, mean age 33.3 years) were enrolled. Localization of the tumor was mainly classified into the lateral ventricle in 91 patients, the third ventricle in 339, the fourth ventricle in 18, the suprasellar region in 75, and other paraventricular areas in 191 patients. The most commonly observed tumors were germ cell tumors in the third ventricle (177 cases [39%]), cystic lesions in the suprasellar region (56 cases [75%]), and astrocytic tumors in the thalamus-basal ganglia (71 cases [38%]). Although 641 (92.8%) of 691 patients could receive neuroendoscopic diagnosis using biopsy, the diagnosis obtained with endoscopic biopsy differed from the final diagnosis based on subsequent craniotomy in 18 patients and clinical course in 3 patients. Of these 21 patients, 7 had astrocytic tumors, 4 had pineal tumors, 6 had germ cell tumors, and 4 had other tumors. The final diagnostic accuracy rate was 89.7%. Associated hydrocephalus was observed in 517 patients (72.4%), of whom 316 and 39 underwent third ventriculostomy and fenestration of the septum, respectively. The response rates were 96.2% and 89.7%, respectively. Third ventriculostomy was required for recurrence of hydrocephalus in 41 patients (13.0%), and the long-term response rate was therefore 83.2% (263 of 316 patients). Perioperative complications other than fever, such as new onset of or progressive hydrocephalus, infection due to CSF leakage, and bleeding in the ventricle or tumor, were found in 81 patients (11.3%). The median Karnofsky Performance Scale score before endoscopic surgery was 80, but it increased to 90 after surgery. The score was thus significantly increased after surgery (p < 0.0001, Mann-Whitney U-test). Activities of daily living after surgery decreased due to perioperative complications in 15 patients (2.1%). The incidence of new dissemination after endoscopic biopsy was 6.8% and not high compared with routine surgical treatment.

Conclusions

The authors concluded that neuroendoscopic diagnosis using biopsy for ventricular and paraventricular tumors is adequately accurate and safe. It was demonstrated that endoscopic procedures play important roles not only in the treatment of hydrocephalus associated with intra- and paraventricular tumors but also in significantly improving ADL. Furthermore, the long-term outcome of endoscopic third ventriculostomy was clearly favorable.