Hiroshi Niizuma

Results of stereotactic aspiration in 175 cases of putaminal hemorrhage.

Believing that improved therapeutic results in cases of intracerebral hematoma might be obtained by minimal invasion of the brain, we used computed tomographic-guided stereotactic aspiration in 175 of 241 patients with putaminal hemorrhage. These patients, who were treated 6 or more hours after onset, had hematomas larger than 8 ml and were unable to raise an arm and/or leg on the affected side. Craniotomy was performed in 15 other patients, most of whom were brought to the hospital with large hematomas within 6 hours of onset. The remaining patients either had mild deficits of consciousness (33 patients) or severe deficits and/or were elderly (18 patients) and were treated conservatively. Thirteen patients (7.4%) showed rebleeding after stereotactic aspiration (6 instances of major and 7 instances of minor rebleeding). Craniotomy and removal of the hematoma were required in three of these patients. Aspiration should be avoided in patients who have a tendency for bleeding, even if mild, because rebleeding occurred in 6 of 23 such patients (26%) in these study. The consciousness level improved in 66 patients (38%), was unchanged in 103 patients (59%), and was worse in 6 patients (3%) 1 week postoperatively. Motor function of the arm improved in 55 patients (31%) and was worse in 23 patients (14%). Six months after surgery, the results for the 175 patients who underwent stereotactic aspiration were: 19% excellent, 32% good, 35% fair, 7% poor, 6% dead, and 1% unknown. For the entire series of 241 patients, the results were: 24% excellent, 26% good, 31% fair, 7% poor, 11% dead, and 1% unknown.(ABSTRACT TRUNCATED AT 250 WORDS)

The development and morphogenesis of the human pituitary gland

SummaryIn order to clarify the environmental factors which are involved in the development of the primordium of the pituitary gland such as cell-cell interactions, a three-dimensional reconstruction of this organ and its surrounding tissues was carried out. Pituitary material was obtained from human fetuses mainly during the period of organogenesis. Rathkes diverticulum was found to stretch rostrally from the stomodeal epithelium to the middle of the mesoderm, and already by the 5th week of fetal growth, it was clearly seen to be involved with the diencephalon. The area of contact between Rathkes pouch and the diencephalon gradually moved from the rostral to caudal regions and, after 13 weeks of development, had a position similar to that found in the newborn infant.Among the cells forming Rathkes pouch, it was found that the closer their relationship was to the diencephalon, the greater were their epithelial characteristics. When the relationship of such cells to the diencephalon was weaker, their differentiation to endocrine cells occurred earlier. Immunohistochemically, that portion of the pituitary primordium which has a close relationship with the diencephalon, later to become the pars intermedia, showed an adrenocorticotropic hormone (ACTH) immunoreactivity later than that of the pars anterior. On the other hand, in the 21st fetal week, nearly all of the cells of the pars intermedia were found to be ACTH-positive. This finding is thought to indicate a close connection between the physical contact between the brai (diencephalon) and the pituitary primordium and the development of the pars intermedia; the differentiation of ACTH cells. The surface of the epithelium of Rathkes cavity continues to increase at least until the 21st fetal week, so the growth of the epithelium of Rathkes pouch is thought to be heavily involved in the growth of the primordium of the pituitary gland in the early stages of development.

CT-Guided Stereotactic Aspiration of Intracerebral Hematoma – Result of a Hematoma-Lysis Method Using Urokinase

CT-guided stereotactic aspiration was performed in the CT room on 97 patients with hypertensive intracerebral hematomas, using a standard ventricular cannula. Residual hematomas were liquefied by urokinase and aspirated through the drainage tube. Major and minor rebleeding were seen in 7 cases. Two out of the 4 major rebleeding cases were followed by craniotomy, while the other cases were treated conservatively. More than 80% of the hematomas were aspirated in 68 cases, 50-70% in 19 cases and 30-40% in 6 cases. Operation in the CT room and hematoma lysis with urokinase is very useful for the aspiration of intracerebral hematomas.

Evaluation of the analgesic effects of capsaicin using a new rat model for tonic pain.

An animal model for tonic pain has been produced by means of injecting monosodium urate crystals into a knee joint of rat hind paws in order to evaluate the analgesic effects of various drugs and analgesic methods and to elucidate the physiology of tonic pain. This model allows for stable and long-term behavioural changes due to tonic pain followed by complete recovery without tissue damages. It is advantageous in allowing for objective and quantitative evaluation of the effects of analgesics and should prove useful in research on pain and the development of pain therapy techniques. Using this model, the analgesic effects of capsaicin was evaluated when administered to the neonatal rat or locally to peripheral nerves. In both cases, significant analgesic effects were obtained.

Spontaneous intracerebral hemorrhage and liver dysfunction.

We evaluated liver function and coagulation parameters in 117 patients with spontaneous intracerebral hemorrhage (68 men and 49 women) admitted to our clinic within 24 hours after onset. Liver dysfunction was more common among men than women due to differences in alcohol consumption. Number of thrombocytes and fibrinogen concentrations were lower, especially among men with elevated concentrations of glutamic oxaloacetic transaminase or glutamic pyruvic transaminase and/or elevated gamma-globulin fraction. Five of the 78 patients undergoing stereotactic hematoma aspiration and one of the 39 treated nonsurgically rebled. All six of the patients who rebled were men, heavy alcohol consumers with liver dysfunction. Fibrinogen concentration was abnormally low in four of the six and at the lower end of the normal range in one. Two showed thrombocytopenia and one case showed prolonged prothrombin time. These facts suggest that liver disorders produce a state in which hemorrhage occurs more readily and that this hemorrhagic tendency may be one of the causal factors of spontaneous intracerebral hemorrhage.

Stereotactic aspiration of putaminal hemorrhage using a double track aspiration technique.

Double track aspiration was used to remove the hematoma between 6 and 24 hours from onset in nine cases of putaminal hemorrhage. This technique was used in cases where an approach along the long axis of the hematoma was not feasible. With this method, aspiration is done at two target points lying anterior and posterior of the somewhat harder central region, at which aspiration is not attempted. This technique allows aspiration of most of the serum components, which are depicted as low density areas in computed tomographic (CT) scans, and some 53 to 85% of the main mass of the hematoma, which is seen on CT as high density areas. There was no rebleeding among these nine patients, and the remaining hematoma in all cases was located between two target points--a fact that is thought to indicate that the central portion of the hematoma is in fact somewhat harder than the peripheral portions. Although the double track aspiration technique has the disadvantage of producing two tracks, it is thought to be an effective method in such cases because it allows safe and thorough hematoma aspiration.

Acoustic neurinoma presenting as subarachnoid hemorrhage

A 49-year-old man who had been suffering from disturbance of hearing for 5 years suddenly developed severe headache, nausea, and vomiting. Computed tomography (CT) scans both with and without contrast medium enhancement, performed on the day of admission, showed a nearly round high-density area in the left cerebellopontine angle. A left transaxillary vertebral angiogram showed no aneurysm or arteriovenous malformation. Hemorrhage from a tumor in the left cerebellopontine angle was suspected. CT scan without contrast medium enhancement, performed on the 17th day after onset, showed only a small, ill-defined high-density area in the cerebellopontine angle. An operation was performed on the 20th day after onset. The tumor was totally extirpated together with a clot. Histologically the tumor was an acoustic neurinoma with hemorrhage and necrosis. The postoperative course was favorable. Massive hemorrhage from primary intracranial tumors, especially acoustic neurinomas, is discussed. Radical operation on the tumor should be performed as soon as possible.

Aneurysms of the azygos anterior cerebral artery

Abstract Two cases of aneurysms of azygos anterior cerebral arteries are reported from among 37 cases of distal anterior cerebral artery aneurysms. The significance of this anomaly in the genesis of anterior cerebral artery aneurysms is discussed.

Influence of liver dysfunction on volume of putaminal hemorrhage.

We studied the relations of age, sex, hypertension, alcohol consumption, liver dysfunction, and thrombocyte count to the volume of the hematoma in 141 patients with spontaneous putaminal hemorrhage. Hematomas were significantly larger in men, regular alcohol consumers, those with liver dysfunction, and those with low platelet counts. Our findings reflect the fact that almost all of the alcohol consumers were men, most of them had liver disorders, and the volume of hematoma in such patients was relatively large.

Computed Tomography-guided Stereotactic Aspiration of Posterior Fossa Hematomas: A Supine Lateral Retromastoid Approach

We report a supine lateral retromastoid approach for computed tomography-guided stereotactic aspiration of hematomas of the posterior fossa. The method involves horizontal insertion of the aspiration needle at the suboccipital region with the patient in a supine position with the head turned 30 to 40 degrees away from the lesion and with slight forward flexion of the neck. Eleven hematomas have been removed through this approach thus far, nine cerebellar and two pontine. With this technique, general anesthesia is not needed and operative invasion is minimal, allowing hematoma aspiration in patients in whom operation would previously not have been indicated. An additional merit is the suitability of this method for elderly patients.