Koichi Inokawa

Primary neurilemoma of the thyroid gland: Report of a case

Neurilemoma, like other non-epithelial tumors, seldom occurs in the thyroid gland. A 57-year-old man was first referred to our hospital with an asymptomatic anterior neck tumor. A solid tumor was detected in the right lobe of the thyroid and an enucleation of the thyroid tumor was performed. The tumor was 35×33×33 mm in size, and diagnosed as Antoni A type neurilemoma. We were only able to find seven previously reported detailed cases of primary neurilemoma of the thyroid gland. A review of these cases, however, revealed that neurilemoma tends to develop in the right lobe of the thyroid gland. An operation is thus considered necessary and an enucleation of the tumor is appropriate.

The role of the liver in the changes of acid-base balance and plasma lipids during surface-induced deep hypothermia.

The role of the liver in the changes of acid-base balance and plasma lipids in surface-induced deep hypothermia for open-heart surgery was investigated clinically and experimentally. The metabolic acidosis generally observed in open-heart surgery under surface-induced deep hypothermia is derived from lactacidemia. Although the accelerated anaerobic glycolysis is partly responsible, the depressed acidic metabolite-disposing ability of the liver also plays an important role. The evidence which is presented to show the decrease of plasma lipids other than NEFA under hypothermia is probably due to the hepatic accumulation of lipids and the decreased lipids release from the liver.

Metabolic Changes in Surface-Induced Deep Hypothermia Combined with Cardiopulmonary Bypass for Cardiac Surgery

Surface induced deep hypothermia combined with cardiopulmonary bypass (combined method) is excellent in open heart surgery of infants which combines each advantage of cardiopulmonary bypass and hypothermia. The present study was performed to investigate pathophysiological changes, especially metabolic changes, in combined method induced by two stressors such as cardiopulmonary bypass and hypothermia. In general, metabolic changes during hypothermia are temporarily enhanced immediately after the start of cardiopulmonary bypass. Lactacidemia and metabolic acidosis are rapidly improved after the start of perfusion rewarming, but abnormality of ceruloplasmin and cholesterol metabolism in the liver and hypopotassemia are not rapidly improved. Therefore, the treatment for these metabolic abnormalities seems to be necessary during and after the procedure.

Scintiscanning demonstration of thymoma: Comparative study on scintiscans using201Tl,67Ga and75Se

Thymus scintigraphy was performed using201Tl-chloride,67-Ga-citrate and75Se-selenomethionine on 30 thymoma patients with or without myasthenia gravis. Mass negativity was observed in 6 out of 17 (35.3 per cent) and 3 out of 13 cases (23.1 per cent), respectively. A rate of 70 per cent (21 cases out of 30) of mass positivity was observed by thymus scan using201Tl. With regard to the relation between thymus scan and cell type,201Tl-scan exhibited a high rate of mass positivity, regardless of the cell type while the75Sescan showed a trend toward mass positivity in epithelial cell predominant cases. With201Tl, mass positivity was observed when the CPM/g ratio for tumors and blood exceeded 3.0. This trend can serve as an index for the suitability of supplementary chemo- and radiotherapies, as well as for prognosis in cases of relapse, and in those for whom excision was not complete.

Somatic and Psychomotor Development of Children after Hypothermic Open-Heart Surgery

One hundred and seven patients with ventricular septal defect who survived one and a half to thirteen years after hypothermic open-heart surgery were reviewed with respect to somatic, intellectual, and psychomotor development. There were no negative effects associated with deep hypothermic arrest in any of these areas. Abnormal electroencephalograms were seen in one-half the number of patients examined, but there was no close relation between the circulatory arrest period and electroencephalographic findings. CT scanning of the brain indicated that the abnormality decreased with the lapse of the time after hypothermic open-heart surgery. It would appear that hypothermic open-heart surgery with limited circulatory arrest is a useful method, providing that the circulatory arrest is not allowed to exceed a limited period. However electroencephalographic assessment suggests that postoperative cerebral abnormalities may occur more frequently than previously suspected, despite the lack of preoperative abnormalities on the electroencephalograms.

Inhibitory mechanisms of insulin secretion associated with hyothermic open-heart surgery

In order to clarify the inhibitory mechanism of insulin secretion associated with open-heart surgery, the influence of insulin antagonistic hormones on insulin secretion was studied in 20 patients with congenital heart diseases undergoing open-heart surgery, under simple deep hypothermia. Despite a hyperglycemia, plasma immunoreactive insulin and C-peptide showed no change during the cooling period, while with the exception of plasma human growth hormone, dopamine-β-hydroxylase, immunoreactive glucagon, cortisol and cyclic AMP in plasma, either showed no change, or a decrease during the cooling period. It is assumed that catecholamine, glucocorticoid and glucagon do not play an important role in the inhibitory mechanism of insulin secretion during hypothermic open-heart surgery, and a transient hypofunction of the pancreas as well as the liver and the adrenal gland is probably involved.

Studies of lipid and carbohydrate metabolism during surface-induced deep hypothermia with circulatory arrest for open-heart surgery

Plasma lipids, blood glucose, plasma insulin (IRI) and serum dopamine-β-hydroxylase (DBH) were measured in 30 subjects undergoing surface-induced deep hypothermia with circulatory arrest for open-heart surgery. Non-esterified fatty acid (NEFA) in the plasma rapidly increased at the lowest temperature (23°C) reached and other lipids in the plasma decreased during the cooling period. An increase of NEFA and a decrease of triglyceride have been attributed to the action of lipoprotein lipase activity stimulated by heparin. It is also likely that the decrease of other lipids and β-lipoprotein in the plasma results from the transient hypofunction of the liver due to hypothermia. Blood glucose increased during the cooling period, while plasma insulin showed no significant change. Serum DBH reflecting catecholamine also showed no significant change during the cooling or rewarming periods. Therefore, hyperglycemia in hypothermic open-heart surgery may result from the decrease of peripheral utilization of glucose and from the inhibition of insulin secretion due to the transient pancreatic hypofunction.