Junichiro Choki

Effect of carotid artery ligation on regional cerebral blood flow in normotensive and spontaneously hypertensive rats.

Regional cerebral blood flow (rCBF) was measured in normotensive rats (NTR) and spontaneously hypertensive rats (SHR), in a lightly anesthetized state and with control of Pacos by artificial ventilation. Without carotid artery ligation, NTR and SHR showed almost identical rCBF values and distribution, despite s gnificantly elevated levels of blood pressure in SHR. Bilateral carotid artery ligation, however, caused much more pronounced decreases of rCBF (ischemia) in SHR than NTR, in regions supplied by the carotid artery. The reduction of rCBF in SHR was rather homogenous and symmetrical. Mechanisms causing the differences between NTR and SHR are discussed.

Cerebrospinal Fluid and Arterial Lactate, Pyruvate and Acid-Base Balance in Patients With Intracranial Hemorrhages

Lactate and pyruvate concentrations and acid-base balance in cerebrospinal fluid (CSF) and arterial blood were determined in patients with intracranial hemorrhages (28 subarachnoid hemorrhages and 15 intracerebral hemorrhages). A greater increase in CSF lactate and lactate-pyruvate ratio (L/P ratio) was observed in patients with impairment of consciousness, focal neurological deficits, poor prognosis, or CSF pressures higher than 300 mm H2O. A combination of CSF lactate greater than 2.5 mM per liter, L/P ratio above 20, bicarbonate less than 20.4 mEq per liter, pH below 7.276, or arterial PCO2 below 31.5 mm Hg seems to indicate a poor prognosis from intracranial hemorrhage. The mechanism of hyperventilation in acute cerebrovascular diseases and of CSF pH regulation in acid-base disturbances was also discussed.

Bordering Zone Hyperemia and Glucose Metabolism in Experimental Cerebral Ischemia

Areas of increased blood flow (hyperemia) at the periphery of ischemic foci have been noted in experimental animals [1]. Experiments using 14C-2-deoxyglucose (2-D G) for the measurement of local cerebral glucose utilization (LCGU) have also demonstrated increased uptake of 2-DG in the bordering zone of focal ischemia [2]. The present study was designed to elucidate the relationship between hyperemia and increased 2-DG uptake in gerbils with unilateral common carotid artery (CCA) occlusion.

Comparative analysis of regional cerebral blood flow measured by 133Xe inhalation technique between embolic and thrombotic cerebral artery occlusion

一定の臨床的診断基準により診断された脳塞栓 (塞栓群) 43例および血栓性脳動脈閉塞症 (血栓群) 43例を対象として, 発症より1ヵ月以上経過した時点での133Xe吸入法による局所脳血流量測定を行った.今回対象となった2群の歩行能力から見た重症度はほぼ一致していた.CT上の梗塞巣の広がりは塞栓群の方が有意に大であったが, 病巣側, 非病巣側それぞれの半球平均脳血流量 (mCBF) は2群間で差がなかった.両群とも病巣側mCBFは非病巣側mCBFに比べ有意に低値であった.転帰を歩行可能と不能とに分けた場合, 歩行可能例のmCBFは不能例のそれに比べ高値であり, 転帰が同じ場合には塞栓群, 血栓群といった病型によるmCBFの差はなかった.両群とも年齢とmCBFとの間に有意の負の相関があり, 塞栓群においてCT上の梗塞巣の広がりとmCBFとの間に強い負の相関が見られた.この2群における慢性期の局所脳血流量の臨床的意義とその差異について考察した.

Embolic intracranial arterial occlusion visualized by non-enhanced computed tomography

心房細動を伴う心臓弁膜症と右大脳半球の陳旧性梗塞を有し, 今回左内頚動脈の塞栓性閉塞をきたした77歳女性例を呈示した.本例の急性期における頭部単純CTにおいて, 左中大脳動脈主幹部と走行が一致し, 正常な脳実質に比べ高いCT値を示す索状構造物が検出された.慢性期のCTでは, この異常な索状構造物の所見は得られなかった.本例の急性期に観察された索状構造物は, 脳主幹動脈を閉塞した栓子ないし閉塞部位より末梢の凝血塊であると推定された.本所見の診断学上の意義について, 若干の文献的考察を交えて論じた.