Alumina ceramic (Bioceram®) is an excellent material that is stable in and compatible with biological tissues, though harder and more fragile than antogenous bone. Recently, new ceramics have been developed for the purpose of overcoming the disadvantages of alumina ceramics. For example, zirconia ceramics have almost the same flexural strength as iron and hydroxy apatite consists of the same molecular elements as autogenous bone. Tissue compatibilities and radiological properties of three ceramics were investigated. First, tissue culture dishes (30 mm in diameter and 5 mm in depth) were made of the three ceramics and the adherence of cultured tumor cells to these dishes at 37°C for 90 minutes were compared with glass dishes and plastic culture dishes (Nunclon®). There was no difference in adherence between alumina ceramics and zirconia ceramics, both of which are superior to hydroxy apatite. Next, the growth rate for 1 week of cultured tumor cells on the ceramic dishes were examined. There were no differences between the three ceramics with regard to doubling time, while the growth rate on alumina ceramics exceeded that of the other ceramics. Thirdly, ceramic pieces were implanted in the parietal bone of mongrel dogs and histological changes, especially new bone formation, were investigated. Tongue-like exostosis of new bone along the ceramic piece was observed 2 months after implantation of alumina ceramic and 3 months for zirconia ceramic. Tissue reaction was slight. Finally, the artifacts of each ceramic on computerized tomography (CT) scan image were investigated. In the application of ceramics to neurosurgical field, artifacts on CT scan are an obstacle. Alumina ceramic showed minimum artifact on CT scan. Alumina ceramic is considered to be the most suitable material among the three ceramics in the neurosurgical field at present.
Local cortical blood flow (LCBF) was measured during extracranial-intracranial (EC-IC) bypass surgery in 14 hemispheres of 12 patients with moyamoya disease, 8 hemispheres of 8 patients with occlusion or stenosis of the internal carotid or middle cerebral artery, and 2 hemispheres of 2 patients with an unruptured internal carotid aneurysm. Measurement of LCBF was performed with the clearance method of hydrogen gas generated by electrolysis (H2-method) and the heat clearance method (heat-method), using the plate type probe in both methods. LCBF measured by the H2-method was distinctly lower in all the patients with occlusive lesions before the EC-IC bypass, than in one patient without occlusive lesions. LCBF after bypass was increased in the territory of the recipient artery of all the patients with occlusive lesions, including moyamoya disease, except for one patient with stenosis of the middle cerebral artery. LCBF was not always increased after bypass in the area apart from the recipient artery, or the area on the opposite side of the Sylvian fissure of the patients with moyamoya disease. The LCBF measured by the heatmethod was hardly decreased by the clamping of the recipient artery in the part near the recipient artery before the bypass. The LCBF measured by the heat-method was promptly decreased by the clamping of the donor artery and increased by the release of the clamp after bypass. According to this evidence, the patency of the anastomosis and the surface area fed by the donor artery were confirmed after bypass. CO2 reactivity was studied by the heat-method in patients with moyamoya disease. In many of them, LCBF was not increased during hypercapnia but was decreased during hypocapnia. In the patients with unruptured internal carotid aneurysm, the heat-method was useful for determining the influence of clamping of the internal carotid artery on the LCBF before permanent ligation of the internal carotid artery. The H2-method is quantitative but interrupted, whereas the heat-method is continuous qualitative. It is quite possible that simultaneous LCBF measurements by both methods during bypass surgery are useful not only for the study of the cerebral hemodynamics but also for the monitoring system during operation.
Optical densities (OD) were measured in ultraviolet absorption ranging from 210 to 310 nm in cerebrospinal fluid (CSF) samples obtained from 33 cases of adult normal pressure hydrocephalus. CSF samples from 100 patients, who had no neurological disorders served as control. All cases of adult normal pressure hydrocephalus were divided into three groups (excellent, good, non effective) according to the clinical improvement following the ventriculo-peritoneal (V-P) shunt operation. Two absorption peaks were ordinarily found in spectrophotometric analysis in CSF. The first peak at 230 nm was identified as the complex of albumin, γ-globulin and a few peptides through various biochemical analyses. The OD at 230 nm were significantly higher in both the excellent and good groups than in the normal control group (P<0.02, P<0.05) . For 24 hours prior to the shunt operation, continuous CSF drainage was made through lumbar route and the samples taken after 24 hours showed marked increases in the OD at 230 nm in the excellent and the good recovery groups. The second peak at 267 nm known as ascorbic acid absorption, remained significantly lower in all three groups than in the control group (P<0.001). Meglumine iothalamate (MI) was found in CSF as the maximum absorption at 245 nm following intravenous administration. Twenty-two samples taken 24 hours after intravenous administration of 100 ml of MI were studied. The OD at 245 nm were significantly higher in the excellent recovery group than the one in the non effective group (P<0.01). The increases in OD at 230 and 245 nm were thought to be due to the impairment of either the blood-brain or blood-CSF barrier and the development of edema in brain parenchyme. The cases who had high OD at 230 nm responded well to the V-P shunt operation. This was probably due to the removal of edema fluid through the hydrostatic pressure gradient between the brain and the ventricle. These results may be useful in deciding on surgical indication on patients of normal pressure hydrocephalus.
Selective catheterization was carried out in fifteen patients with Cushing's disease and one patient with Cushing's syndrome, and venous samples were obtained for the measurement of adrenocorticotropic hormone (ACTH). Transsphenoidal microsurgery revealed pituitary adenomas in fifteen patients. In nine of the fifteen patients, ACTH levels in the inferior petrosal sinus or jugular vein were unequivocally higher than the simultaneous peripheral value. The ratios were greater than 2.0 with a range of 2.2 to 9.5. The ratios in the superior vena cava and inferior vena cava were smaller than 2.0 except in one case. When the peripheral mean ACTH values were raised, the ratios in the jugular vein tended to be greater. In five patients with pituitary microadenoma bilateral inferior petrosal sinuses or jugular veins were successfully catheterized, and in four of them the results of selective venous sampling were correlated with the laterality of pituitary microadenoma. In one patient without pituitary adenoma, the peripheral mean ACTH value was very high, and the ratios in the inferior petrosal sinus and jugular vein were smaller than 2.0. Selective venous ACTH sampling from the inferior petrosal sinus or jugular vein is a useful aid for the differential diagnosis of Cushing's syndrome, when standard clinical and biochemical studies are inconclusive, and in diagnosing the localization of pituitary adenoma.
A stereotaxic biopsy was carried out in 6 cases of deep-seated brain tumors, utilizing a “BioTac biopsy cannula”(manufactured by the Progress Mankind Technology, Co., U.S.A.). The tumors were located in the basal ganglia (2 cases), lateral ventricle (2 cases), thalamus (1 case) and parietal subcortex (1 case). Sufficient amounts of tumor specimens were obtained in all the cases to establish the histological diagnosis. The histology was germinoma in 2 cases, glioblastoma in 2 cases, astrocytoma (grade 2) in 1 case and metastatic adenocarcinoma in 1 case. Neurological deterioration occurred after biopsy in the case with a metastatic brain tumor in the lateral ventricle that had already shown signs of increased intracranial pressure and disturbance of consciousness. In retrospect, stereotaxic biopsy should not be done in such a case, unless a decompressive procedure is performed at the same time or prior to biopsy. “BioTac biopsy cannula” is essentially a modification of the instruments originally designed by Backlund, or Coe, et al. The cannula is introduced into the target location with the inner stylet. After removal of the inner stylet, the inner spiral tip cannula is slowly turned to the depth of the tissue required for sampling. Then, the outer cannula is advanced to capture the spiral tip containing the tissue specimen and finally the entire cannula assembly is removed to retrieve the tissue sample. The advantage of using this instrument is its ability to obtain tissue specimens even from firm solid tumors without difficulty. It is believed that this cannula should be added to the surgical armamentaria of every modern neurosurgical service.
Types of diffuse brain injury (DBI) were classified based on a study of fifty patients with acute, severe head injuries. This study focused on findings of computed tomography (CT) and outcomes of the patients. The level of consciousness was estimated by the Glasgow Coma Scale; greater than 8 in 28 cases; 8 or less in 22 cases. The overall mortality rate was 28%, however the rate ranged from 8 to 67%, depending on the type of DBI. CT findings of DBI within 24 hours after head injury were classified into 5 types: diffuse cerebral swelling (DC S), isodense hemispheric swelling (IHS), deepseated brain injury (DSI), subarachnoid hemorrhage (SAH) and normal findings. DSI demonstrated the highest mortality rate (67%), and IHS was the second (50%). However, there are many pediatric cases with excellent outcomes. Although both DCS and IHS occurred frequently in children, it was considered that these two conditions should be distinguished, because of the existence of some differences in the clinical course of the two. There were only 7 cases of SAH alone, but SAH was the most frequent associated finding in DBI, existing in 50% of 50 cases. SAH per se could not be regarded as a poor prognostic factor. It is the authors' impression that DBI without coup or contre-coup injuries can be readily diagnosed by CT scan and that DBI is an important clinical factor in the closed head injury cases.
A rare case of cystic craniopharyngioma with spontaneous shrinkage of the cyst is reported. The patient, a 43-year-old male was referred because of visual field defect, transient disturbed consciousness and abnormal computerized tomography (CT) findings. Contrast enhanced CT scans showed a suprasellar cystic lesion with a high density nodule. Repeated CT scans revealed spontaneous shrinkage of the cystic lesion. The decrease in size of the cyst correlated well with the improvement of disturbed consciousness. An operation was performed, and the histopathological diagnosis was craniopharyngioma. It is believed that the shrinkage of the cyst seen in the present case was caused by spontaneous rupture of the cyst wall. Spontaneous rupture of the cyst wall in cases of craniopharyngioma is extremely rare. Only 6 cases have been reported including 2 in which shrinkage of the cystic craniopharyngioma was confirmed.
A case of multiple cerebral tuberculomas associated with tuberculous brain abscess is presented. The characteristics of computed tomography (CT) appearance, diagnosis, pathology and treatment of cerebral tuberculoma are discussed. The patient, a 67-year-old female, was initially admitted to a sanatorium for the treatment of lung tuberculosis. She developed headache and nausea with mental confusion. She was then transferred in November 1982. A neurological examination showed that she was in a confused state, and that she had dysarthria, papilledema, neck stiffness and left hemiparesis. Enhanced CT scans showed multiple lesions, some of which were homogeneously enhanced and others were ring-like enhanced. A right occipital craniotomy was performed and a mass was excised en bloc. The mass contained purulent material. Acid-fast bacillus stain of the pus was positive and histological examination of the capsule wall demonstrated tuberculoma. Three weeks later, a right temporal craniotomy was performed, because the right temporal lesion grew rapidly. The same histological findings were obtained. Antituberculous chemotherapy was continued. One month later, the homogeneously enhanced lesions almost disappeared. However, the ring-like enhanced lesions kept growing to become multiple large masses. In January 1984, the patient remained stuporous.
A 14-year-old boy who had had a ventriculo-peritoneal shunt procedure for the post-meningitic hydrocephalus at the age of 12 was admitted with a left ophthalmoplegia in 1980. On admission, he had a low grade fever and leucocytosis but the causative agent was not identified by cerebrospinal fluid culture. Computerized tomography (CT) revealed presence of a slight high-density area in the suprasellar region with diffuse enhancement which led to diagnosis of suprasellar germinoma. Irradiation of 2, 000 rads, however, did not produce any marked changes in CT. Because of severe liver dysfunction, a direct operation was postponed. About 30 months later, he was re-admitted in a drowsy state due to shunt dysfunction. CT disclosed that the left foramen of Monro was obstructed by a suprasellar tumor. Intracapsular removal of the tumor through a left frontal craniotomy was performed. Pathological diagnosis was granuloma and numerous fungus hyphae were found in the central part of the necrotic tissue. Periodic acid-Schiff staining showed non-septate fungi which were interpreted as mucormycetes. Postoperative examination of the other organs including the paranasal cavity did not show any abnormality. Following the administration of amphotericin B and 5fluorocytosine, the patient recovered and was discharged. Cerebral mucormycosis often causes occlusion of large cerebral vessels by hyphae formation and also causes massive cerebral hemorrhages. Cerebral mucormycosis is one of the most fulminant types of fungal infections and the chronic type with granulation observed in this case is a very rare phenomenon. The authors discuss the significance of the serial CT findings and the importance of anti-fungal drug administration.
A case of brain metastasis of liver cancer is reported. A 47-year-old male was admitted with the episode of sudden onset left hemiparesis and conjugate deviation toward the right. Computerized tomography at admission showed three high density areas with perifocal edema, in the right temporal, parietal and posterior lobes. The right carotid angiogram showed abnormal feeding vessels from the middle cerebral artery and tumor stain in the right temporal lobe. His conscious level deteriorated quickly, therefore a large right craniotomy and evacuation of the hematomas were performed. However, he did not recover and died 4 days later. Post-mortem examination revealed a primary liver cancer (hepatocellular carcinoma) and metastatic foci in the brain, dura mater, skull, adrenal glands and lungs. The tumor cells were found in the clot which had been evacuated at the operation and in the parenchyma around the hematoma cavities at the post-mortem examination. Therefore, it was concluded that two large hematomas in the parietal and occipital lobes were caused by the metastatic nodules and the temporal lesion was the tumor itself.
The mechanism of the production of the intracerebral hematoma in cerebrovascular moyamoya disease is still being debated. The authors experienced a case, whose intracerebral hematoma was evacuated 18 hours after the ictus. During the operation, a hematoma ball near the bleeding point in the hematoma cavity was extirpated and used for preparing pathologic specimens. Four hundred serial specimens, 4 μm in thickness, showed abnormal perforating arteries, the diameter of which was around 300 μm. The wall of these vessels presented variable intimal elastofibrosis and tortuosity of internal elastic laminae, resulting in irregular narrowing or dilatation of vessels. In addition, many disrupted arterioles, the size of which ranged from 50 to 150μm in diameter, were found. The walls of these smaller vessels were not accompanied by the fibrinoid necrosis change and presented almost the same changes as were seen in the larger ones, but to a smaller extent. These arteriolar changes were considered to evolve during the formation of the hematoma. So long as there is production of intracerebral hematoma, these findings indicate that the pathologic mechanisms in moyamoya disease are similar to those in hypertensives, especially in the massive type.