Toshiki Endo, Yasuko Yoshida, Reizo Shirane and Takashi Yoshimoto
Reizo Shirane, Takeo Kondo, Yasuko K. Yoshida, Susumu Furuta and Takashi Yoshimoto
✓ A rare case of cerebral pseudoaneurysm located at the internal carotid artery (ICA) was caused by the removal of a ventricular catheter in an infant. This 4-month-old girl underwent ventriculoperitoneal shunt revision, during which the old ventricular catheter was removed from the posterior horn of the left lateral ventricle, but the choroid plexus was pulled out by the tip of the catheter. Intraventricular hemorrhage (IVH) and subarachnoid hemorrhage were observed postoperatively. Magnetic resonance (MR) angiography performed on the 12th postoperative day revealed ICA stenosis and aneurysm formation at the C1 portion of the left ICA. Contrast-enhanced computerized tomography (CT) scans obtained on the 21st postoperative day revealed recurrent IVH and enlargement of the lesion. The patient underwent surgery for treatment of the aneurysm. Operative findings revealed a pseudoaneurysm arising from the left ICA at the proximal end of the anterior choroidal artery (AChA). The aneurysm was removed and the wall of the ICA was reconstructed. Postoperative three-dimensional CT scanning and MR angiography demonstrated disappearance of the aneurysm and preservation of the ICA. The patient was discharged without additional neurological deficits.
Many complications, including IVH, are associated with removal of a ventricular catheter. This case shows that pseudoaneurysm formation can occur in a remote region due to avulsion of the AChA from the ICA. In most circumstances a ventricular catheter can be removed without difficulty. However, precision and caution should be exercised when removing a ventricular catheter.
Yasuhiro Suzuki, Yasuko K. Yoshida, Reizo Shirane, Takashi Yoshimoto, Mika Watanabe and Takuya Moriya
✓ Reports of angiosarcoma arising in the central nervous system are rare. The authors present the case of a 30-day-old infant with clinical manifestations of projectile vomiting and tense anterior fontanelle resulting from a left frontotemporal tumor. Total excision of this highly vascular, well-circumscribed tumor was performed without incident, and histopathological examination revealed a malignant angiosarcoma. Immunohistochemical reaction of the neoplastic cells was diffusely positive for endothelium-specific antigens including factor VIII-related antigen, CD31, and CD34. The final diagnosis of congenital primary cerebral angiosarcoma was thus confirmed. The patient's postoperative course was uneventful, and he was discharged 2 weeks after the operation. He was in good condition with no sign of recurrence after 11 months; follow-up computerized tomography, magnetic resonance (MR) imaging, and abdominal ultrasonography studies demonstrated no tumor regrowth. The characteristic findings for this tumor on MR imaging, the immunohistochemical findings, and surgical outcome are discussed.
Reizo Shirane, Toshihiro Kumabe, Yasuko Yoshida, Ching-chan Su, Hidefumi Jokura, Kunihiko Umezawa and Takashi Yoshimoto
Object. To determine the safety and usefulness of performing surgery via the occipital transtentorial approach to treat anterosuperior cerebellar tumors, evaluation of 14 patients was performed over a 5-year period.
Methods. The study was performed in 14 patients, aged 6 months to 71 years, who harbored anterosuperior cerebellar tumors of the posterior fossa including four hemangioblastomas, three cerebellar astrocytomas, three medulloblastomas, two metastatic tumors, one recurrent astrocytoma, and one rhabdoid cell tumor. All patients underwent surgical treatment by the same surgical team and via the same surgical approach. Endoscopy combined with neuronavigation was used for large, deep-seated tumors extending to the fourth ventricle. Of the 14 patients, total or gross-total removal was achieved in 12 patients and subtotal removal in two patients. There was no incidence of mortality or morbidity in the 14 patients, and all functional outcomes were good to excellent postoperatively. Postoperative magnetic resonance imaging revealed that none of the patients had suffered brain damage or infarction around the cerebellum, brainstem, or occipital lobe.
Conclusions. Although this study was the first in which a specific examination of the efficacy of the occipital transtentorial approach in patients with anterosuperior cerebellar tumors was undertaken, our findings suggest that this surgical approach is very useful, safe, and accurate for removing the primary tumor and evaluating the surrounding anatomy, as well as for determining operative strategy.