Biomedical subjects
Publications and source records attributed to J Handa.
Ischemic neuropathy is a previously described but rarely encountered complication of therapeutic embolization. Two cases of peripheral facial nerve palsy following embolization of branches of the external carotid artery are reported, and the possible mechanism is discussed.
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An intracranial dermoid cyst presenting as a radiolucent mass on the plain radiographs of the skull is described.
Early clinical manifestations and radiologic features of tuberous sclerosis were studied in 18 consecutive patients encountered in the past two years, including two patients harboring an associated intraventricular tumor (giant-cell astrocytoma). Depigmented naevi rather than adenoma sebaceum, infantile spasms and intracranial calcifications were the cardinal early features in this present series, and CT scanning proved to be the single most useful diagnostic technique in the early detection of intracranial calcifications and therefore for the early diagnosis of this disorder. CT scanning was also useful in detecting the intraventricular tumors in the early stage before they became clinically manifest.
Cerebrovascular effects of YC-93, a new 1,4-dihydropyridine derivative, was examined in experimental animals and in human patients using a variety of methods. YC-93 in doses ranging from 0.001 to 0.03 mg/kg i.v. increased regional cerebral cortical blood flow and cerebral venous outflow in anesthetized dogs, and internal carotid blood flow in anesthetized monkeys. The increase in cerebral blood flow was accompanied by an increase in oxygen delivery to the brain and an elevation of cerebrospinal fluid pressure. Both intracarotid injection and intraduodenal administration of YC-93 also resulted in cerebral vasodilation in monkeys. In patients with cerebrovascular diseases and other chronic diseases, measurements of cerebral blood flow by 133-xenon clearance method showed that an intracarotid injection of 1 microgram/kg of YC-93 increased cerebral blood flow by 28.8% without changing arterial blood pressure and arterial pCO2, and that an intravenous injection of 0.01 mg/kg of YC-93 increased cerebral blood flow by 17.0% with a minimal decrease in the arterial blood pressure but without changing arterial pCO2. Thus, YC-93 produced a potent cerebral vasodilation not only in experimental animals but also in human patients in the same dose, and seemed to act perhaps directly on the cerebral vascular beds.
Three cases of epidural hematoma with delayed clinical course are presented. In each patient, computed tomography (CT) initially failed to show typical biconvex, high density extra-axial lesion. The correct diagnosis was reached only after injection of contrast medium revealed enhancement of the border of the hematoma. Importance of contrast enhancement in selected patients with head injury is stress, and the mechanism of rim enhancement is discussed.
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Chronic toxicity and its recovery of pepleomycin sulfate was studied in both sexes of beagle dogs. At dose levels of 0.3, 0.15 and 0.075 mg/kg, pepleomycin was administered intramuscularly to dogs for 180 successive days. Two dogs of the 0.15 mg/kg dose group were used for recovery test for 35 days. As general findings, the decrease of food intake, the loss of body weight, ulceration of foot pad, nail root necrosis and onychoptosis, ulcer of tongue and labia, and alopecia, dermatitis and necrosis at friction sites were observed more severely in the 0.3 mg/kg dose group of both sexes, especially in male, than those in bleomycin were. In the dose groups of 0.15 and 0.075 mg/kg, their findings were observed as slightly as those in bleomycin were. The death occurred in the 0.3 mg/kg dose group of both sexes. The lesions of liver and kidney were recognized in the 0.3 mg/kg dose group of both sexes, severely in male, on histopathological findings. Additionally severe fibrosis of lung was observed in one of the 0.3 mg/kg dose group of female. In general chronic toxicity of pepleomycin was revealed more severely in the 0.3 mg/kg dose group than that of bleomycin was, but in the dose groups of 0.15 and 0.075 mg/kg difference between their toxicities was not significant. In addition, chronic toxicity of pepleomycin in dogs showed more severely in male and its recovery was hardly recognized during its period. The maximum safety dose in this studies was estimated to be between 0.075 and 0.15 mg/kg in dogs.
Using specimens obtained at operation, tissue-blood ratios of iodinated contrast material (iodine), and in some cases also those of red blood cell tracer (51Cr), were measured in 23 patients with various kinds of intracranial mass lesions. Results provided confirmatory evidence on the major role played by extravascular iodine in the positive enhancement effect with computed tomography.
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Computed tomography (CT) scans in two young patients with xeroderma pigmentosum with neurologic manifestations (De Sanctis-Cacchione syndrome) showed ventricular dilatation and cerebral cortical atrophy. The brainstem appeared small. In addition, an abnormal thickening of the calvarial bones was noted in both patients. These CT findings of the brain were compared with the neuropathologic features of this syndrome reported in the literature.
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Effects of cholinergic inhibition by atropine on cerebral circulation were studied in 15 baboons anesthetized with sodium pentobarbital. Intravertebral infusion of atropine, 0.1 mg/kg, did not cause any changes in cerebral blood flow (CBF), superior sagittal sinus wedge pressure (SSWP), epidural pressure (EDP), cerebral perfusion pressure, or cerebral vascular resistance under normal conditions. Cerebrovascular responsiveness to carbon dioxide (CO2) inhalation was not influenced by atropine. The presence of cholinergic nerve fibers has been proved in the cerebral blood vessels and the existence of cholinergic mechanism suggested in the brain stem, but it is not likely that the cholinergic nerves have tonic control of cerebral blood vessels in the resting state or affect cerebrovascular responsiveness to CO2. The changes in EDP and those in SSWP showed a very good correlation to each other. There was also a good correlation between the changes in CBF and those in EDP or SSWP.
Five patients with giant intracranial aneurysms were studied by computed tomography. Secondary intracranial changes such as hemorrhage, cerebral infarction and communicating hydrocephalus are easily demonstrated by computed tomography. In addition, computed tomography provides precise information concerning the actual size and location of large but partially thrombosed or calcified aneurysm to better advantage than angiography.
Computed tomographic (CT) findings of low-density lesions of the brain were compared with the pathologic nature of the lesions. Twenty-one lesions having densities uniformly lower than those of the normal brain, most of which showing no significant early enhancement effect, were selected. Such lesions were either cystic non-neoplastic lesions, cystic tumors, solid tumors or solid but non-neoplastic lesions. Although CT proved to be the single, most sensitive diagnostic method detecting such low-density lesions, it was often difficult or even impossible to differentiate cystic from solid, or neoplastic from non-neoplastic lesions based on the CT features alone.
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