Tetsuo Wakao

Spontaneous resolution of chronic subdural hematomas.

Four patients with chronic subdural hematomas, all of which resolved spontaneously, were followed from the time of injury to resolution of the chronic subdural hematoma. Periodic computed tomographic (CT) scans showed spontaneous resolution 78, 174, 231, and 326 days after the development of the chronic subdural hematoma, respectively. Features of the CT scans and a possible mechanism of spontaneous resolution are discussed.

Giant Serpentine Aneurysm of the Posterior Cerebral Artery

We are reporting an unusual case of a giant serpentine aneurysm of the posterior cerebral artery (PCA). We were unable to find a report in the literature of a similar aneurysm. The microsurgical pterional approach was used for temporary clipping of the P-2 segment of the PCA, and the aneurysm was trapped successfully and excised. The discussion includes the operative approach to the giant serpentine aneurysm.

Intracranial granuloma caused by Aspergillus fumigatus.

A case is reported of intracranial granuloma caused by Aspergillus fumigatus involving the anterior cranial fossa and the frontal lobe. In this case, clinical symptoms developed about 5 years before the diagnosis was made. The final diagnosis was made by a craniotomy. The patient was treated with an extensive excision and chemotherapy, but finally he failed to respond to these treatments. We compile a summary of reported cases with a tabulation of pertinent information and discuss the pathogenesis, prognosis, and difficulty in treating this infection.

Brain stem necrosis after irradiation of pituitary adenoma

Abstract A case of late delayed necrosis in the left temporal lobe, midbrain, and pons following irradiation of a pituitary adenoma is reported. In this patient, disturbance of consciousness appeared just after removal of the necrosis of the temporal lobe which had been considered preoperatively to be a temporal lobe tumor; autopsy also revealed radiation necrosis in the midbrain and pons. Radiation necrosis, especially of the brain stem, after pituitary irradiation is reviewed, and the mechanism of development of disturbance of consciousness after removal of the necrosis of the temporal lobe in this case is discussed.

Epidermoid tumors of Meckel's cave: case report and review of the literature.

Lesions of Meckels cave are extremely uncommon and difficult to diagnose. The symptoms and signs are variable, and the lesions may not appear on routine roentgenographic or computed tomographic examination. A patient with a small epidermoid tumor of Meckels cave that was diagnosed by magnetic resonance imaging is herein reported. The epidermoid appeared as a low-intensity mass on the T1-weighted image and as a high-intensity mass on the T2-weighted image. Coronal sections defined the anatomic relationship to the trigeminal nerve. Preoperative recordings of the trigeminal sensory evoked response may be predictive of postoperative recovery of neurological deficits. Furthermore, intraoperative recording was extremely useful in avoiding inadvertent neurological injury. Review of the literature confirms the rarity of this lesion and the usefulness of magnetic resonance imaging in diagnosing it, although based on a limited number of cases.

The Incidence of Delayed Traumatic Intracerebral Hematoma with Extradural Hemorrhages

After introduction of computerized tomography (CT), we experienced 22 patients with traumatic extradural and intracerebral combined hematomas, of whom 15 underwent sequential CT scans. In 14 of the 22 patients or 13 of the 15 patients whose initial CT scans were performed early, within 6 hours after injury, intracerebral hematomas developed more slowly than extradural hematomas. In ten of the 13 patients, development of intracerebral hematomas was demonstrated only after removal of extradural hematomas, and in four patients acute brain swelling was observed during surgery. Therefore it is emphasized that the incidence of post-surgical intracerebral hematoma with extradural hemorrhages is high and that acute brain swelling during surgery for extradural hematomas is largely caused by the delayed intracerebral hematomas.

Epidermoid Tumors of Meckelʼs Cave: Case Report and Review of the Literature

: Lesions of Meckels cave are extremely uncommon and difficult to diagnose. The symptoms and signs are variable, and the lesions may not appear on routine roentgenographic or computed tomographic examination. A patient with a small epidermoid tumor of Meckels cave that was diagnosed by magnetic resonance imaging is herein reported. The epidermoid appeared as a low-intensity mass on the T1-weighted image and as a high-intensity mass on the T2-weighted image. Coronal sections defined the anatomic relationship to the trigeminal nerve. Preoperative recordings of the trigeminal sensory evoked response may be predictive of postoperative recovery of neurological deficits. Furthermore, intraoperative recording was extremely useful in avoiding inadvertent neurological injury. Review of the literature confirms the rarity of this lesion and the usefulness of magnetic resonance imaging in diagnosing it, although based on a limited number of cases.

Traumatic extradural hematomas with delayed development.

After introduction of computerized tomography (CT), we experienced 74 patients with 78 traumatic extradural hematomas. Among these, 16 hematomas were subjected to sequential CT examinations in the early stage after injury. Four hematomas of four patients became enlarged, and another five hematomas of four patients were delayed. Accordingly the delayed extradural hematomas are thought to be less uncommon than previously believed. Three patients with four delayed extradural hematomas of surgical significance are reported, and pathogenesis of the delayed extradural hematoma is discussed.

Malignant melanoma of the spinal epidural space metastasized from the enucleated left eye after nine years without symptoms: report of a case.

A case of flaccid paraplegia due to a metastatic spinal epidural melanoma is reported. Symptoms occurred approximately 9 years after the enucleation of the left eye. A solid melanotic mass was removed almost totally. Three years after the operation, the patient had not regained the motility of the lower limbs. The need for long term follow-up and management of patients with such problems is discussed, and the pertinent literature is reviewed.

Successful treatment of a basilar aneurysm presenting as a brainstem hemorrhage

A case of large brainstem hemorrhage resulting from a basilar artery aneurysm is reported. This extremely rare disorder is fatal in a large majority of cases, and has usually been reported after autopsy. This case presents a successful recovery after clipping the aneurysm.