Kenzo Matsuoka

Intracellular calcium levels in canine basilar artery smooth muscle following experimental subarachnoid hemorrhage : an electron microscopic cytochemical study

SummaryChanges in intracellular calcium levels in canine basilar arterial smooth muscle were semiquantitatively measured by an electron microscopic cytochemical technique using a combined oxalate-pyroantimonate method. Measurements made after subarachnoid hemorrhage were compared with those made after contraction induced by prostaglandin F2α. Fifteen minutes after topical application of the drug, when the basilar artery was constricted by 20%, 15% of smooth muscle cells contained a large amount of intracellular calcium. One hour later, the diameter of the basilar artery and intracellular calcium precipitation returned almost to control levels. Fifteen minutes after the first intracisternal injection of autologous blood, when acute vasospasm was angiographically evident, 13% of smooth muscle cells contained a large amount of calcium. After 1 h, when acute vasospasm had already abated, the number of smooth muscle cells containing a large amount of calcium markedly increased to 37% and some smooth muscle cells showed early degenerative findings such as intracytoplasmic vacuoles including calcium accumulation. After 48 h, when delayed vasospasm had already started, the calcium deposits and early degenerative changes had decreased significantly. After 49 h and 4 days (1 h and 48 h after the second injection of blood), the change in the amount of calcium was the same as at 1 h and 48 h after the first injection, respectively, but degeneration of smooth muscle cells increased. Therefore, acute vasospasm after subarachnoid hemorrhage may be caused by an initial elevation of intracellular calcium levels, as is the case with drug-induced contraction. Delayed vasospasm may be initiated by an excessive influx of calcium accompanied by early degeneration of cells within a few hours after subarachnoid hemorrhage. This may be followed by persistent contraction of smooth muscle cells in a low concentration of intraccllular calcium and by progressive structural derangement.

Successful treatment of adult arnold-chiari malformation associated with basilar impression and syringomyelia by the transoral anterior approach

A case of adult type I Arnold-Chiari malformation associated with basilar impression, syringomyelia, atlantoaxial dislocation, and occipitalization of the atlas is reported. Preoperative magnetic resonance imaging clearly revealed evidence of severe anterior compression of the cervicomedullary junction due to basilar impression and a sharp clivoaxial angle. Therefore, transoral anterior decompression and fusion were performed, resulting in an improvement of the patients neurologic signs and symptoms. Postoperative magnetic resonance imaging showed an obvious reduction of the tonsillar herniation and syringomyelia, as well as an improvement of the cervicomedullary compression.

A cerebral neuroblastoma with extracranial metastases

A rare case of cerebral neuroblastoma with extracranial metastases is reported. This patient was followed for over ten years. The biopsy specimen of the brain tumor taken at the first operation revealed the architecture of a poorly differentiated ependymoma having perivascular rosettes. The histological pattern of the second biopsy taken eight years after the first operation was highly cellular and vascular with abundant mitoses, showing Homer-Wright rosettes. The histological diagnosis of this second specimen was a cerebral neuroblastoma. The problem of the multipotentiality of the brain tumor is discussed.

Aneurysm of the anterior inferior cerebellar artery at the internal auditory meatus.

An aneurysm of the anterior inferior cerebellar artery extending into the internal auditory meatus is reported. The patient developed headache and vomiting caused by a subarachnoid hemorrhage, and rapidly showed signs and symptoms of a lesion in the cerebellopontine angle soon after the onset. At operation, a clip was successfully applied to the neck of the aneurysm. The characteristic clinical findings are briefly reviewed.

Single photon emission computed tomography (SPELT) using N-isopropyl-p-(123I)iodoamphetamine (IMP) in the evaluation of patients with epileptic seizures

To evaluate the clinical usefulness of IMP SPECT in the diagnosis of epilepsy, 6 normals and 52 patients in the interictal phase were studied. Thirty min after an intravenous injection of 111 MBq IMP, SPECT was performed using a rotating gamma camera. Of 21 patients with simple partial seizures, a localized decrease of uptake was shown in 16, and an increase in 3. Topologically, these findings corresponded well to the ictal symptoms. Nine of 13 patients with localized epileptic EEG had a good correspondence between the findings on EEG and IMP SPELT. In 20 of 23 with complex partial seizures, the coronal images showed laterality of uptake in the temporal lobes, whereas the CT was normal in 14. However, these findings on IMP SPECT agreed with the EEG in the temporal leads in only 5 cases. Of 8 patients with primary generalized seizures, a diffuse cerebral decrease was shown in 3 of 4 patients with convulsive seizures (grand mal), and a normal uptake in 3 of 4 patients with non-convulsive seizures (petit mal). However, 2 patients showed a localized decrease, therefore, we determined that they suffered from partial seizures evolving to secondarily generalization. From these data, we concluded that IMP SPELT could be a useful method in the diagnosis of epilepsy.

Brain abscess secondary to intracranial extradural epidermoid cyst

A case of brain abscess in the right temporal lobe secondary to an intracranial extradural epidermoid cyst in the right parasellar region is reported. The etiology of the brain abscess in this particular case was deduced using the findings of computed tomography, carried out several times over a 3-year period, after an initial operation to remove the epidermoid cyst. One of the scans showed a very-low-density spot in the right parasellar region compatible with air, suggesting a communication between the intracranial space and the paranasal sinuses.