Toshikazu Takeshima

Importance of prevention of intravenous thrombosis and preservation of the venous collateral flow in bridging vein injury during surgery: An experimental study ☆

BACKGROUND Venous infarction (cerebral edema and/or hemorrhage) may occur several hours after sacrifice of the bridging vein during surgery. However, in our experience, severe venous infarction is often produced by prolonged brain retraction in addition to sacrifice of the vein. METHODS The experiment was carried out using 20 adult cats. In five cats, all bridging veins were coagulated near the superior sagittal sinus and 12 hours later the surgical wound was closed (group A). In five other cats, a round plate weighing 45 g was placed on the center of the Sylvian fissure for 12 hours and then the wound was closed (group B). In the remaining 10 cats, both of these interventions were performed (group C). All 20 animals were sacrificed 12 hours after the wound closure. RESULTS The degree of Evans-blue dye leakage and brain edema was much more marked in the group C than in groups A and B. The endothelial intactness of the bridging veins studied by staining with a factor VIII-related antigen was much more disturbed in group C than in the other groups. CONCLUSIONS The endothelium of the cortical veins is damaged much more by the combination of sacrifice of the vein and brain retraction, and this endothelial damage of the cortical vein leads to extensive venous infarction.

Secretory meningioma with elevated serum carcinoembryonic antigen level

We recently encountered a 68-year-old woman with right sphenoid wing meningioma of the secretory type accompanied by an elevated serum carcinoembryonic antigen level. This case was neuroradiologically characterized by marked brain edema. Histologically, the lesion was rated as having meningothelial components and was rich in blood vessels and pseudopsammoma bodies. Carcinoembryonic antigen, epithelial membrane antigen, keratin, and cytokeratin were immunohistochemically detected in the pseudopsammoma bodies and the cells producing these bodies.

Quantitative Topography of the Hemodynamic-Oxidative Metabolic Interrelation by Multispot Measurement Approach in Rat Ischemia Models

We applied the multispot measurement approach for both laser Doppler (LD) and a microspectrophotometric method to measure local cerebral blood flow (1CBF) and local tissue hemoglobin oxygenation (IHbO2). We demonstrated that the current technology permits in vivo observation, allowing us to establish a close topographical relation between CBF and HbO2. We measured 1CBF by LD flowmetry and tissue HbO2 by a microspectrophotometric method at multiple corresponding locations using a “scanning” technique that employs a computer-controlled micromanipulator. CBF and HbO2 data from predefined locations were correlated to the topographical situation and then arranged in a three-dimensional (3D) image using xyz triplet columns for a mesh and scatter plot. The quantitative topography of the hemodynamic-metabolic interrelation was studied using two experimental models: ischemia/reperfusion (experiment 1), and sinus-vein thrombosis (experiment 2) in rat brain. Using the scanning technique we determined misery and luxury flow (postischemic hyperperfusion) compared with oxygen metabolism in experiment 1 and drainage of desaturated blood via collateral pathways, although detected as flow, in experiment 2. The technique, including the scanning procedure, is useful for showing sequential changes of the hemodynamic-metabolic interrelations of the brain cortex. The technique could reveal phenomena previously undetected by traditional techniques.

Direct Surgery for Cerebral Arteriovenous Malformation After Superselective Intravascular Embolization

Embolization is used as a radical therapy, as well as an adjunctive therapy with surgery for cerebral arteriovenous malformations (AVM). Eight patients underwent endovascular embolization and then surgical resection for cerebral AVM. In two cases, although AVM was embolized completely on the digital subtraction angiographical (DSA) evaluation, slight arterial blood filling into the nidus of AVM was observed on the surgical exploration. Postoperative computerized tomography (CT) demonstrated extent infarction area which was seemed secondary to occlusion of feeding arterial trunk due to retrograde thrombosis from nidus, although new neurological deficits were not recognized because of infarction in the non-dominant temporal lobe. In three cases, embolization of AVM was partial, because catheterization into the all feeding arteries was difficult. But, in two cases who had AVM in the right temporal and in the left occipital lobe respectively, surgical removal of AVM was performed completely without excessive hemorrhage. In another case who had AVM in the corpus callosum, although AVM was smoothly removed, the patient died of postoperative pulmonary embolism. In three cases, AVM could not be embolized at all because of impossible catheterization into feeding arteries. Histological findings of removed AVM which was completely embolized angiographically demonstrated that embolus mainly existed in the nidus and draining veins, and existence of blood around the embolus in these vessels. These histological findings and the our intraoperative obseravation of slight arterial blood inflow into the nidus in the angiographically complete embolized AVMs imply that AVM should be removed surgically, even if it is embolized sufficiently. We must not forget that angiographical complete embolization of AVMs may provoke infarction of the normal brain around them, although they can be removed surgically without difficulty by the embolization.