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Biomedical subjects

K Obara

Publications and source records attributed to K Obara.

261 records · Page 15Linked to original sources

Gallbladder perforation: color Doppler findings.

Gallbladder (GB) perforation is a life-threatening complication of acute cholecystitis, and early diagnosis prevents delay in patient management. We present two cases of GB perforation diagnosed by color Doppler ultrasonography. Each clearly showed a flow signal passing through the perforated site, leading to prompt and successful surgical treatment. This interesting observation suggests that color Doppler ultrasonography is useful in the diagnosis of GB perforation.

Acute Disease↗

Leuko-araiosis and cerebral perfusion in normal aging.

To clarify the incidence, age relationships and pathogenesis of white matter lesions of unknown origin (leuko-araiosis) detected by neuroimaging among normal elderly volunteers, we measured the severity of leuko-araiosis using computerized tomographic (CT) densitometry among 42 healthy self-supporting men and women of different ages, all with normal neurological and cognitive test performance. Results were correlated with local cerebral perfusion using xenon-contrasted CT. The 42 volunteers, who are followed in this laboratory for studies of normal aging, were divided into two groups in order to determine aging effects by an extremes design. One group consisted of 19 adults below age 60 (M = 53.3, SD = 6.0). The index group comprised 23 individuals all over the age of 60 (M = 71.6, SD = 8.7). Leuko-araiosis around the anterior horns of the lateral ventricles (frontal leuko-araiosis) was more severe (p < .01) among the older group, however, occipital leuko-araiosis did not significantly differ between older and younger groups. Cerebral perfusion in frontal, temporal, and parietal cortex was decreased among older compared with younger volunteers (ps < .001, .01, and .05, respectively). Multiple regression analyses disclosed significant and direct relationships between severity of frontal leuko-araiosis and (a) frontal cortical atrophy and (b) reductions of cerebral perfusion within frontal white matter and caudate nucleus. We conclude that cortical atrophy with hypoperfusion and ischemia of frontal white matter play a part in the pathogenesis of frontal leuko-araiosis associated with normal aging and this may be a predictor for later cognitive declines.

Adult↗

Cognitive performance after small strokes correlates with ischemia, not atrophy of the brain.

Computerized tomographic measures of recurrent cerebral infarctions, atrophy and local perfusion were all prospectively correlated with cognitive testing during treatment of risk factors plus antiplatelet therapy among vascular dementia patients. Neurological and cognitive status were quantified among 22 demented patients with small strokes and compared with 22 age-matched normal volunteers. In vascular dementia, risk factor control plus antiplatelet therapy reduced cerebral infarctions, increased perfusion, and stabilized or improved cognitive test performance, despite age-related, progressive cerebral atrophy.

Aged↗

Cerebral circulatory changes during migraine headache with aura.

Many authors report alterations of cephalic (both intracranial and extracranial) blood flow and vascular responsiveness in patients with migraine. In the majority of reports, rCBF has been decreased during the prodromal phase and increased during and immediately after the headache phase of migraine attacks. Abnormal vascular responsiveness has been demonstrated, not only during each attack, but also between attacks. Pharmacological and therapeutic evidence that many vasoactive agents induce, prevent or abolish attacks of migraine headache are consonant with the close relationships that exist between vascular abnormalities and the pathogenesis of migraine with aura. This is particularly true of the marked therapeutic effectiveness of calcium entry blockers, which are effective in the prophylaxis of migraine, and sumatriptan, which has direct vasoconstrictive effects, with relief of the headache, which lends strong support to a vascular hypothesis.

Brain↗

Germanium poisoning: clinical symptoms and renal damage caused by long-term intake of germanium.

We report five patients who have taken inorganic germanium preparations over a prolonged period. In all cases, the renal function deteriorated with no proteinuria or hematuria. Histological examination of the kidneys showed widespread tubular degeneration and interstitial fibrosis with minor glomerular abnormalities. Most patients had gastrointestinal symptoms such as vomiting, anorexia and weight loss; one patient had peripheral neuropathy and myopathy. A considerable amount of germanium was detected in the hair or nails of these patients. These cases clearly show that abuse of inorganic germanium compounds can induce renal damage with various extrarenal manifestations.

Aged↗

Comparative study of cytology and punch biopsy in cervical intraepithelial neoplasia during pregnancy. A preliminary report.

To elucidate the accuracy of cytology in diagnosing cervical intraepithelial neoplasia (CIN) during pregnancy, cytologic screenings for uterine cervical cancer in pregnant women were reviewed for a five-year period. Of the 967 pregnant women screened, abnormal cytologic findings were recorded for 15 (1.6%). Only nine of these were subsequently examined by colposcopy and punch biopsy, which demonstrated CIN in all cases, for an incidence of documented CIN during pregnancy of 0.93%. Including two referral cases also examined by colposcopy and biopsy, cytology and histology agreed on the degree of CIN in four cases and disagreed by one degree in four cases, by two degrees in two cases and by three degrees (mild dysplasia versus carcinoma in situ) in one case. Review of the specimens from these cases did not readily explain the poor concordance between cytology and punch biopsy; some findings suggest that overestimation of the punch biopsy sample may be the explanation.

Adult↗