Makoto Negoro

Primary Choroid Plexus Papilloma Located in the Suprasellar Region: Case Report

A 34-year-old woman with primary choroid plexus papilloma occurring in the suprasellar region is reported. No connection with the ventricular system was found during intraoperative observations. The findings of pathological examinations such as hematoxylin and eosin staining, transthyretin (prealbumin) immunoreactivity, and electron microscopy were consistent with choroid plexus papilloma. Radiologically, it was extremely difficult to differentiate from tuberculum sellae meningioma. To our knowledge, this is the first case of primary choroid plexus papilloma in this location reported in the literature.

Pineal Tumors: clinical diagnosis, with special emphasis on the significance of pineal calcification.

The clinical presentations, findings of neuroradiological examinations, laboratory findings, pathological diagnoses, methods of treatment, and results of follow-up of 43 cases of pineal tumor collected at the Nagoya University Hospital from 1958 to 1979 are reviewed. The definitions of calcification of the pineal body and of pineal tumor are given. There is a significant difference in the incidence of calcification of the pineal body between pineal teratomas and pineal germinomas. Although there is a 100% rate of calcification of the pineal body in cases of pineal germinoma, the rate is very low in cases of pineal teratoma; calcification appears in only a small percentage of the cases of teratoma mixed with germinoma or embryonal carcinoma, or both. In male patients with suprasellar germinoma, there is a high frequency of an associated pineal calcification. No pineal calcification is seen in cases of basal ganglia germinoma. The computed tomographic (CT) findings of pineal teratoma and germinoma are characteristic. CT scanning is superior for early diagnosis of suprasellar and basal ganglia germinomas.

Micro force sensor for intravascular neurosurgery and in vivo experiment

Catheter is one of the medical tools for endovascular surgeries, and it is frequently used for neurosurgical operations. There is, however, a problem that doctors operate a catheter without any force information during their operation, and this problem causes fatigue of doctors. To solve this problem, we propose a micro force sensor for intravascular neurosurgery. This micro force sensor can be installed on the tip of the catheter. The diameter of this sensor is 1.5 mm and length is 12 mm. Using this micro force sensor, we can measure the contact force between the catheter and blood vessels. To express the contact force between catheter and blood vessels is very effective for safe operation. In this paper, we show the structure of the micro force sensor and its characteristics, and also we present the result of an in vivo experiment.

Telesurgery System for Intravascular Neurosurgery

The intravascular neurosurgery is one of the most successful minimally invasive surgery. However, the difficulty to operate a catheter inside the cranial blood vessels because of the complexity and narrowness of blood vessels checks increasing the number of well-skilled doctors. Moreover the X-ray camera, which is used during an operation, causes the X-ray exposure to a doctor. One of the solution to these problems is telesurgery system.

Dural carotid cavernous sinus fistula presenting as isolated oculomotor nerve palsy

We report five patients with dural carotid cavernous sinus fistula presenting with isolated oculomotor nerve palsy. All patients were older women with a fistula derived from the internal carotid artery, who had early filling of the supero-posterior cavernous sinus, followed by drainage posteriorly into the inferior petrosal sinus, with low shunt flow. The hypothesized pathogenesis was nerve compression by an expanding sinus, or ischemic neuropathy secondary to venous congestion or arterial steal. Dural carotid cavernous sinus fistula must be considered in patients presenting with isolated oculomotor nerve palsy.

Embolisation of cerebral arteriovenous malformations to assure successful subsequent radiosurgery

This study investigated the angiographic changes in embolised arteriovenous malformations (AVMs) pre- and post-embolisation and preradiosurgery to clarify the usefulness of embolisation as a pretreatment for radiosurgery and the strategy of embolisation for the radiosurgical success. A total of 37 patients with cerebral AVMs treated over a period of 4 years was investigated. All the AVMs were embolised with N-butyl cyanoacrylate and 2 months later they were treated by radiosurgery. The size of AVM nidus reduced just following the embolisation (mean 21.9 ml to 3.9 ml). The angiogram taken in preparation for radiosurgery showed a further size reduction in the nidus of 16 AVMs, no change in 10 and regrowth in 11. In all the cases where size was reduced, the nidus was densely packed, while all the regrown AVMs were of the diffuse type. Five AVMs disappeared following radiosurgery, all of which were size-reduction or no-change cases. In conclusion, to achieve success in subsequent radiosurgery, nidus embolisation and the occlusion of fistulous and meningeal feeders are mandatory. Imprudent proximal feeder occlusion and the use of embolic materials with a risk of recanalisation should be avoided to prevent regrowth of the nidus, which may lead to errors in planning the radiosurgery to follow.

Contribution of meningeal arteries to cerebral arteriovenous malformations.

SummaryWe studied 52 patients with cerebral arteriovenous malformations (AVMs) by selective angiography and found that half received supply from meningeal branches of the external carotid artery. The frequency of meningeal arteral contribution was significantly higher in superficial AVMs, especially in the temporal, parietal and occipital regions. Larger lesions and higher shunt with steal phenomena on angiography were other factors favouring a meningeal arterial contribution. Diffuse AVMs with pial arterial networks around the nidus commonly received meningeal blood supply. In the past, meningeal feeders have been though to be congenital, but this study suggests that they may develop during growth of the AVM.

Extracranial vertebral artery aneurysm with neurofibromatosis

SummaryAn extracranial vertebral artery aneurysm in a patient with neurofibromatosis is described. The aneurysm was treated by endovascular balloon occlusion of the proximal vetebral artery. The details of the therapeutic management are discussed, and the vascular manifestations of neurofibromatosis are reviewed.

Cerebral oxygenation state in childhood moyamoya disease: a near-infrared spectroscopy study

Near-infrared spectroscopy was used to measure the relative concentration changes of oxygenated hemoglobin (HbO(2)), deoxygenated hemoglobin (HbR), and total hemoglobin (t-Hb) before, during, and after hyperventilation in eight patients with childhood moyamoya disease who underwent surgery. The patients were divided into the following two groups: those with and those without re-build-up phenomenon on electroencephalography. All patients except one exhibited decreased concentrations of HbO(2) and t-Hb during hyperventilation and decreased concentrations of HbO(2) and increased concentrations of HbR after hyperventilation. The difference between the hemoglobin concentration during and after hyperventilation was significantly greater in the group with the re-build-up phenomenon than the group without it (P <0.03, Mann-Whitney U test). The patients with the re-build-up phenomenon had lower HbO(2) and higher HbR concentrations after hyperventilation. The concentrations of HbO(2) and HbR reflect an alteration in the oxygenated blood supply and/or oxygen use. Thus, it is strongly suggested that regional cerebral hypoxia and metabolic oxygen disturbances play an important role in the occurrence of the re-build-up phenomenon. Near-infrared spectroscopy is a useful noninvasive method to evaluate the efficacy of surgical treatment in childhood moyamoya disease.

The occipital-vertebral anastomosis as a collateral pathway: hemodynamic patterns--case report.

The authors describe the case of a 67-year-old man with acquired obstruction of the common carotid artery and a large, direct occipital-vertebral artery anastomosis bridging the vertebral and carotid artery systems. They discuss the hemodynamics within this type of anastomosis in the context of cerebrovascular occlusive disease and outline their classification of the hemodynamic patterns that have been observed. Surgical procedures for occlusive disease in the presence of such anastomoses are also addressed.