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R Maeyama

Publications and source records attributed to R Maeyama.

13 recordsLinked to original sources
PubMed1999

Benign mediastinal teratoma complicated by cardiac tamponade: report of a case.

We present herein the case of a 48-year-old woman with a benign mediastinal teratoma that had been followed up for 3 years, who developed acute cardiac tamponade. The patient had initially undergone an exploratory sternotomy, at which time the tumor was histologically diagnosed as a benign mature teratoma that could not be resected due to its severe, wide adhesion to the surrounding organs. However, following the development of cardiac tamponade, both sternotomy and right intercostal thoracotomy were employed, and the tumor could be excised with cardiopulmonary bypass standby. High levels of amylase and carbohydrate antigen 19-9 were revealed in the pericardiac effusion fluid. The mRNA expression of inflammatory cytokines including interleukin-1 (IL-1), IL-6, and IL-8 in the tumor tissue was also demonstrated by a reverse transcriptase-polymerase chain reaction analysis. This case illustrates the ultimate natural course of benign mediastinal teratoma and emphasizes the importance of early surgical excision, even when this tumor is asymptomatic.

Base Sequence↗
PubMed1998

A large inflammatory polyp of the gallbladder masquerading as gallbladder carcinoma.

An inflammatory polyp of the gallbladder is a rare variant of benign gallbladder polyp. Differentiation between an inflammatory polyp and polypoid gallbladder carcinoma is difficult when the polyp is more than 1 cm in diameter. We report a rare case of a large inflammatory polyp of the gallbladder masquerading as gallbladder carcinoma in a 37-year-old Japanese woman who was incidentally diagnosed with a large gallbladder polyp, measuring 1 cm in diameter, by ultrasonography. She was asymptomatic and physical examination was unremarkable. Abdominal ultrasonography and endoscopic ultrasonography revealed three polypoid lesions in the gallbladder. One lesion was an isoechoic polyp, measuring 15 x 8 mm, showing a nodular surface and located in the fundus of the gallbladder. The other two lesions were hyperechoic polyps, measuring 5 x 5 mm, in the body of the gallbladder. Computed tomography and magnetic resonance imaging revealed marked enhancement of the largest polypoid lesion by dynamic study, and no lymph node enlargement was noted. Endoscopic retrograde cholangiography revealed a 12 x 8 mm polyp with an irregular surface in the fundus of the gallbladder. Superselective angiography of the cystic artery revealed neovascularity and a tumor stain in the fundus of the gallbladder. Cholecystectomy with lymph node dissection was performed. Intraoperative frozen section diagnosis of the largest polyp was an inflammatory polyp of the gallbladder. The other two polyps were cholesterol polyps. Inflammatory polyp should be considered as a differential diagnosis of hypervascular gallbladder polyps that measure more than 1 cm in diameter.

Adult↗
PubMed1997

Successful treatment by direct hemoperfusion of coma possibly resulting from mitochondrial dysfunction in acute valproate intoxication.

PURPOSE: We evaluated the efficacy of direct hemoperfusion (DHP) for treatment of acute valproate (VPA) intoxication and speculate on the biochemical perturbations that suggest a mechanism of coma induced by VPA overdose. PATIENT AND METHODS: The comatose patient was hospitalized approximately 6 h after ingesting 18 g VPA. DHP, with 200 g activated charcoal, was performed for 6 h. The plasma concentrations of VPA and Glasgow coma scale scores after admission were estimated. Before and after DHP, urine samples were tested in serial fashion for VPA metabolites, organic acids, and acyl carnitine esters of fatty acids. RESULTS: Plasma VPA was efficiently adsorbed on activated charcoal. The patient's plasma concentration of VPA decreased from 471 microg/ml (2,830 microM) to 45 microg/ml (270 microM), at which point the patient became alert. The half-life (t1/2) of VPA was calculated as 4.4 h before DHP and as 1.8 h during DHP. Before DHP, lactate and VPA-glucuronide markedly increased in urine samples, but beta-keto-VPA, a major mitochondrial metabolite, was not detected. Urinary excretion of carnitine esters of medium chain (C8-C10) dicarboxylic acids was increased. After DHP, lactate and VPA-glucuronide decreased, but a significant amount of beta-keto-VPA was demonstrated. Carnitine esters of medium chain dicarboxylic acids were decreased. CONCLUSIONS: DHP with activated charcoal was effective treatment for the patient with acute VPA intoxication and coma. The onset of coma may have been related to inhibition of beta-oxidation in the mitochondria, which was reversible by elimination of plasma VPA by DHP.

Acute Disease↗
PubMed1995

Hemifacial spasm resulting from cerebellopontine angle lipoma: case report.

A case of hemifacial spasm associated with a cerebellopontine angle lipoma is described. Both the seventh and the eighth cranial nerves were incorporated and distorted within this tumor, which seemed to be the cause of hemifacial spasm and other cranial nerve dysfunctions, but obvious vascular elements were not included. To identify a cerebellopontine angle lesion as a lipoma is very important in surgical management. Magnetic resonance imaging is essential to the differential diagnosis of the cerebellopontine angle lesion.

Aged↗
PubMed1987

[Therapeutic problems in aged patients with intracranial aneurysms].

In a series of 404 patients with intracranial saccular aneurysm, 61 were over 65 years of age. Ten of these aged patients had no surgery. The operative mortality in the aged patients was 11.8%. While the mortality rate in patients below 65 years was 6.1%. The main complication following intracranial surgery for aneurysm consisted of cerebral infarction due to vasospasm, hydrocephalus, intracranial hematoma and general complications. The incidence of angiographical vasospasm was 22.6% in the aged patients and 43.6% in the young patients. There is no significant difference in vasospasm following subarachnoid hemorrhage between the aged and young patients. Cerebral infarction occurred in 27.5% of the aged patients and in 24.6% of the young patients. Severe cerebral infarction was found in 92.9% of the aged patients and in 58% of the young patients. Vasospasm resulted in broad cerebral infarction significantly more frequently in the aged patients, but cerebral infarction proved was non-fatal in the aged patients. Ventricular dilatation detected by CT was found in 33.3% of the aged patients and in 24.2% of the young patients. In patients with ventricular dilatation, 82.4% of the aged patients needed ventriculo-peritoneal shunt (V-P shunt). On the other hand, 39.3% of the young patients had V-P shunt. There was no significant difference for ventricular dilatation detected by CT between the aged and young patients. The aged patients depended on V-P shunt significantly more than did the young patients.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗
PubMed1985

Relationship between the microfilarial migration and the changes of sleep stage with special reference to REM sleep.

Eleven subjects with filariasis were investigated for the relationship between the microfilarial migration and the changes of sleep stage with special reference to REM sleep. Tests on ten patients except one case revealed that the sleep of each case showed a highly consistent pattern from the viewpoint of the first night. Microfilariae were counted every hour and at each REM stage. From these data, the characteristic findings were observed as follows: 1) Microfilarial migration reached the maximum peak around midnight, showing a Poisson type distribution, even though, one case slept only 47 minutes throughout the night, having no REM sleep. 2) Suppression of microfilarial migration during REM sleep was noted in 72%, which was independent of the slow wave sleep. Finally, suppression of microfilarial migration during REM sleep is discussed from the point of view of Hawking's pendulum model and physiological phenomena of REM sleep.

Adolescent↗