Sonomi Sato

Perinidal dilated capillary networks in cerebral arteriovenous malformations.

OBJECTIVEThe perinidal vascular structures of cerebral arteriovenous malformations were examined, to clarify their pathomorphological features. METHODSTwenty-two resected specimens of human brain structures adjacent to the nidus were examined. The vessels surrounding the nidus were three-dimensionally reconstructed with a computer graphics system. RESULTSIn all cases, the analysis of serial sections revealed that perinidal dilated capillaries were located in brain tissue 1 to 7 mm from the nidal border. The vessels surrounding the nidus demonstrated markedly dilated capillary networks (perinidal dilated capillary network [PDCN]). The diameters of the vessels forming the PDCN were 10 to 25 times those of normal capillaries. The PDCN connected not only to the nidus, feeding arteries, and draining veins, via arterioles and venules, but also to the normal capillary network, arterioles, and venules. CONCLUSIONWithout exception, each nidus was accompanied by a PDCN, which connected not only to the nidus, feeding arteries, and draining veins, via arterioles and venules, but also to normal capillaries, arterioles, and venules. The PDCN should be considered in studies aimed at gaining an understanding of the mechanisms underlying the intraoperative and postoperative bleeding, growth, and recurrence of surgically treated cerebral arteriovenous malformations.

The surgery of ruptured and unruptured cerebral aneurysms using three-dimensional CT angiography without conventional catheter angiography

Abstract The object of this study is to assess whether aneurysm surgery can be performed in patients with ruptured and unruptured cerebral aneurysms by using three-dimensional computerized tomography angiography (3D-CTA) alone, without conventional catheter angiography (CCA). We have operated on 153 consecutive patients with ruptured aneurysms and 89 patients with unruptured aneurysms based on 3D-CTA findings since December 1996 and February 1997, respectively. In the cases of ruptured aneurysm, 153 ruptured aneurysms including 62 associated unruptured aneurysms were detected by 3D-CTA. CCA was performed in 7 of 153 patients after they underwent 3D-CTA, which included four dissecting vertebral artery (VA) aneurysms, two basilar artery (BA) tip aneurysms, and one BA–superior cerebellar artery (SCA) aneurysm. In 89 patients with unruptured aneurysms, 101 unruptured aneurysms were detected by 3D-CTA. In 5 of 101 unruptured aneurysms, which included giant or large aneurysms and a case of an aneurysm associated with infarction, CCA was needed. All of the ruptured and unruptured aneurysms were confirmed during surgery and treated successfully. The authors stress that 3D-CTA could replace CCA in the diagnosis of saccular aneurysms and that surgery could be performed in almost all ruptured and unruptured aneurysms by using only 3D-CTA without CCA.