Hiroyuki Yoshioka

Recurrence of meningiomas

Macroscopic total resection with removal of involved dura and bone does not always prevent the recurrence of meningioma of histologically benign subtype. Many causative factors have been investigated, although the mechanism of recurrence remains unclear. Vascular endothelial growth factor (VEGF) is a key factor in meningiomas neovascularization, and the authors investigated whether VEGF expression can predict the recurrence of histologically benign meningiomas after macroscopic total resection.

Expression of Survivin in Astrocytic Tumors Correlation with Malignant Grade and Prognosis

Astrocytic tumors are the most common tumors of the central nervous system. The mechanisms of genetic change of astrocytic tumors have not been understood completely. Recently, survivin has been identified as a member of the inhibitor‐of‐apoptosis family. Survivin expression is considered an important prognostic factor of many tumors.

Intracerebral hematoma in patients with ruptured cerebral aneurysms

BACKGROUND Intracerebral hematoma from ruptured aneurysms is one of the unfavorable factors for outcome in patients with subarachnoid hemorrhage. In this study, the clinical characteristics of intracerebral hematoma in patients with ruptured aneurysms were examined. METHODS The subjects were 512 patients who had been admitted by day 3 after aneurysmal rupture without episodes of rebleeding before the initial computed tomography (CT) scan. They were divided into two groups according to the findings of initial CT; groups 1 and 2 comprised patients with and without intracerebral hematoma, respectively. RESULTS Of the 512 patients, intracerebral hematoma was observed in 98 (19%). The incidence of intracerebral hematoma was higher in patients with distal anterior cerebral and middle cerebral artery aneurysms, compared with those at other sites (both, p < 0.01). Interhemispheric, callosal, and temporal lobe/sylvian hematomas were observed more frequently in patients with anterior communicating, distal anterior cerebral, and middle cerebral artery aneurysms, respectively, than in those with aneurysms at other sites. The incidence of rebleeding was 22% in group 1 and 14% in group 2 (p < 0.05). Clinical grades on admission were higher and outcome at 6 months after onset was less favorable in group 1 than in group 2 (both, p < 0.01). The larger the intracerebral hematoma, the higher was the clinical grade and the less favorable the outcome. However, when comparing management and surgical outcome under the same clinical grades, there was no significant difference between the two groups. CONCLUSIONS There was a close correlation between the site of hematoma and that of the ruptured aneurysm. Poor outcome in patients with intracerebral hematoma seems to be related to severity of clinical grade on admission.

Chronic hydrocephalus in elderly patients following subarachnoid hemorrhage

BACKGROUND With the aging of the population, surgery for ruptured intracranial aneurysms is increasing among the elderly. We sought to clarify the characteristics of chronic hydrocephalus following aneurysmal subarachnoid hemorrhage (SAH) in elderly patients. METHODS Of the 576 surgically treated patients, 289 were aged 59 years or younger, 169 were 60 to 69, and 118 were 70 years or older. The relationship between chronic hydrocephalus and the causative factors was analyzed for each age group. RESULTS Of the 576 patients, chronic hydrocephalus was observed in 215 (37%), with the incidence increasing significantly with age (p < 0.001) and being the highest in the oldest age group. In elderly patients, the incidence of chronic hydrocephalus was relatively high, even after mild SAH. The incidence of chronic hydrocephalus was high regardless of age in patients with severe SAH, such as in those with H&H grades III-IV, SAH grades III-IV, acute hydrocephalus, symptomatic vasospasm, and intraventricular hemorrhage, and in those with vertebro-basilar artery aneurysms. CONCLUSION In the elderly, the incidence of chronic hydrocephalus following SAH was significantly higher than in younger patients, even after mild SAH. In elderly patients, careful observation and individualized treatment are necessary even if SAH is mild.

Interhemispheric arachnoid cyst in the elderly: case report and review of the literature

BACKGROUND Preoperative differential diagnosis of interhemispheric cysts is sometimes difficult. CASE DESCRIPTION We recently experienced a case of symptomatic interhemispheric arachnoid cyst in a 62-year-old woman. We reviewed interhemispheric arachnoid cysts in the elderly and the management of symptomatic interhemispheric arachnoid cysts in elderly patients. Symptomatic interhemispheric arachnoid cysts in the elderly are predominantly located on the right side, have a long history of progressive symptomology, occur predominantly in females, and have no communication with the subarachnoid space. Interhemispheric arachnoid cysts are usually not associated with agenesis of the corpus callosum in elderly patients, whereas interhemispheric nonarachnoid cysts are usually associated with agenesis of the corpus callosum, which will be clearly demonstrated on magnetic resonance imaging. CONCLUSIONS It is highly possible that an interhemispheric cyst without agenesis of the corpus callosum in an adult is an arachnoid cyst.

Spontaneous disappearance of a middle cranial fossa arachnoid cyst after suppurative meningitis

BACKGROUND Spontaneous disappearance of an arachnoid cyst is very rare, particularly after suppurative meningitis. CASE REPORT A 2-month-old boy with a high fever was diagnosed with suppurative meningitis by cerebrospinal fluid examination. Computed tomography disclosed a large arachnoid cyst in the left middle cranial fossa. Two months later, the meningitis was cured. The arachnoid cyst disappeared with long-term antibiotic therapy alone. CONCLUSION Although an infected arachnoid cyst may disappear with antibiotic treatment alone, careful observation and individualized patient management are essential.

Transsphenoidal “Cross Court” Approach Using a Slightly Modified Speculum to Reach Pituitary Adenomas with Lateral Growth

Summary¶ Background. The purpose of this study was to evaluate the usefulness of an oblique “cross court” transsphenoidal approach using a speculum with slightly modified projections for pituitary adenomas showing lateral extension. Method. The projection of the speculum on the side of the cavernous lesion was shortened by 5 mm. The tip of the longer projection was placed in the sphenoid sinus, while the end of the shorter projection was placed on the concha sphenoidalis. An oblique transsphenoidal view was then easily obtained by opening the speculum. The contralateral nasal incisura had to be widened in some cases to achieve a more oblique view. Findings. Twenty-eight patients diagnosed with pituitary adenoma showing lateral growth underwent adenomectomy under direct observation of the medial portion of the cavernous sinus using this approach. Postoperative normalization of hyperendocrinopathy or gross total removal of the tumour was achieved in the majority of patients. Interpretation. An oblique transsphenoidal approach using this speculum and contralateral minor maxillary osteotomy afforded a direct view of the medial cavernous sinus, sufficient for the removal of adenomas showing minor to moderate lateral growth.

p16 gene transfer increases cell killing with abnormal nucleation after ionising radiation in glioma cells

It is well established that cells synchronised at the G1–S phase are highly radiosensitive. In this study, p16-null human glioma cell lines were induced into G1 cell cycle arrest by adenovirus-mediated p16 gene transfer, and examined for radiation-induced cell killing. Clonogenic analysis and trypan blue extraction test showed that the p16 gene transfer enhanced radiation-induced cell killing in p16-null glioma cell lines. TUNEL assays and pulse-field gel electrophoresis confirmed that the radiation-induced cell killing of p16-transfected cells could be caused by a nonapoptotic mechanism. Gimsa staining demonstrated that irradiation alone or Ax-mock infection plus irradiation results in a slight increase in the frequency of cells with abnormal nucleus, compared to unirradiated uninfected or Ax-mock infected cells. However, Ax-hp16 or Ax-hp21 infection alone modestly increased the frequency of cells with abnormal nucleus (especially bi- and multinucleation), and 4-Gy irradiation of Ax-hp16 or Ax-hp21 infected cells substantially enhanced this frequency. These results suggest that there exists some unknown interaction between radiation and p16 in cytoplasm/membranes, which decreases cytokinesis and promotes abnormal nucleation. Thus, p16 expression prevented radiation-induced apoptosis by promoting abnormal nucleation, thereby leading to another mode of cell death.

De novo distal posterior cerebral artery aneurysm.

BACKGROUND De novo aneurysms in the posterior circulation are very rare. The authors describe a first case of ruptured de novo posterior cerebral artery (PCA) aneurysm in the P3 portion. CASE DESCRIPTION A 52-year-old woman with ruptured de novo P3 aneurysm was treated by early endovascular obliteration using Guglielmi Detachable Coils (GDC). To prevent vasospasm, she received postoperative treatment with a hypertensive hypervolemia dilution and a calcium antagonist. She was discharged without neurologic deficits. CONCLUSIONS Aneuryms arising from peripheral segment of PCA are rare, and delayed surgical clipping has been recommended for these lesions. This is the first report of a de novo P3 ruptured aneurysm treated by endovascular embolization using GDC in the acute stage of subarachnoid hemorrhage. The characteristics of de novo posterior circulation aneurysms and the strategy for the distal PCA aneurysms are discussed.

Usefulness of color Doppler sonography in a growing skull fracture: case report.

A case of an 11-month-old infant with a growing skull fracture is described. The patient was admitted with disturbance of consciousness and left hemiparesis after a severe head injury. A pulsating protrusion appeared over the fracture line 1 month later. Color Doppler sonography revealed cerebral herniation and cystic lesion via the bony defect, together with an intracranial arterial flow pattern detected in the extracranial space. Color Doppler sonography was very useful in the diagnosis of growing skull fracture and in the evaluation of the intracranial state, including hemodynamics in this case. Successful surgical treatment was performed on the basis of sonographic data and the patient was discharged 3 months later without motor deficits.