Underlying Venous Pathology Causing Perimesencephalic Subarachnoid Hemorrhage

Abstract

638Perimesencephalic subarachnoid hemorrhage (PSH) has become well recognized as a distinct type of subarachnoid hemorrhage (SAH). This clinical entity of unknown etiology is defined as blood in the cisterns around the midbrain. Perimesencephalic subarachnoid hemorrhage constitutes approximately 10% of all patients with SAH and two thirds of those with a normal angiogram 1-3 . Patients with PSH have an excellent outcome without increased morbidity or mortality from recurrent bleeding and ischemia [3][4][5] . Both venous and arterial sources of bleeding have been suggested 3,5,6 to explain this distinct subset of SAH. Definitive evidence supporting either of these speculations, however, still remains elusive. We report here three cases of PSH that most likely have arisen from an underlying abnormality in the venous system. The presence of underlying venous pathology predisposed the draining venules to rupture, ultimately leading to PSH. The authors speculate that the underlying venous pathology in our cases could provide theoretical clues to the anatomic origin of PSH in general.ABSTRACT: Background: Perimesencephalic subarachnoid hemorrhage (PSH) is a relatively benign clinical entity with a low risk of recurrent bleeding. The precise etiology of PSH has not yet been determined. We report here three cases of PSH with clinical and radiological features that support a venous system as a cause. Case Presentation: The first patient, a 72-year-old woman, had PSH and venous hemorrhagic infarct in the left thalamus on non-contrast CT. Subsequent cerebral angiography revealed widespread thrombosis in the cerebral venous system, a potential cause for reflux overflow hemorrhage. The second patient, a 55-year-old man with an established diagnosis of neuro-Behçet's disease, a well-known cause for cerebral venulitis, presented with PSH one year later. The third patient, a 39-year-old female, with incomplete Behçet's disease was admitted with PSH. Discussion: Current concepts on the anatomic origin and the possible pathophysiologic mechanism leading to PSH are discussed. The underlying pathological conditions in the venous system in our cases provide theoretical clues to the anatomic origin of PSH in general.RÉSUMÉ: Pathologie veineuse sous-jacente causant une hémorragie sous-arachnoïdienne périmésencéphalique. Contexte : L'hémorragie sousarachnoïdienne périmésencéphalique (HSP) est une entité clinique relativement bénigne comportant un risque faible de saignement récurrent. L'étiologie précise de l'HSP n'a pas encore été déterminée. Nous rapportons trois observations d'HSP ainsi que les manifestations cliniques et radiologiques qui sont en faveur d'un lien de causalité avec le système veineux. Observations : La première patiente, une femme âgée de 72 ans qui a subi une HSP, présentait un infarctus hémorragique veineux dans le thalamus gauche à la tomodensitométrie sans substance de contraste. Des angiographies subséquentes ont montré une thrombose étendue du système veineux cérébral, une cause potentielle de l'hémorragie par...

Perimesencephalic nonaneurysmal subarachnoid hemorrhage caused by transverse sinus thrombosis

“…[ 27 ] Intracranial venous hypertension has been considered as the pivotal factor in the pathogenesis of PNSAH. [ 8 , 11 , 13 , 14 , 17 ] Elevated intracranial venous pressure can lead to vessel engorgement and venous rupture. This hypothesis is supported by reports on PNSAH induced by straining, physical exertion, [ 11 ] performing Valsalva maneuvers, and hypoxic training during swimming.…”

“…[ 7 , 12 – 14 ] The presence of underlying anomaly in cerebral venous circulation, such as stenosis of straight sinus, [ 9 ] jugular vein, [ 8 ] and vein of Galen, [ 12 , 15 , 16 ] has been implicated in several case reports as an important predisposing factor in the pathogenesis of PNSAH. [ 9 , 15 – 17 ]…”

Subarachnoid Hemorrhage, Intraparenchymal Hemorrhage and Cerebral Infarction Have Seen a Case of Had Neurobehçet's Disease

“…Behçet hastalığında intraparankimal ve subaraknoid hemoraji nadir de olsa görülebilir. [6][7][8][9][10][11][12][13] Behçet hastalığında santral sinir sistemi tutulumunun mekanizması hâlâ tam olarak bilinmemektedir. Olası model endotel işlev bozukluğu ve trombofili yönündedir.…”

“…16 Bizim yaptığımız araştırmada, literatürde Behçet hastalığı ile beraber perimezansefalik SAK'ın görüldüğü üç olgu mevcuttur. 6 Behçet hastalığında birincil subaraknoid hemorajinin kaynağı tartışmalıdır. Arteriyel veya venöz yırtığa bağlı olabileceği tahmin edilmektedir.…”

“…6,[17][18][19] Perimezansefalik kanamanın kaynağını gelişen venöz sinüs trombozu sonrası perimezensefalik bölge venlerinin geriye doğru hidrostatik basınç artışına bağlamışlardır. 6,16 Bizim olgumuzda herhangi bir sinüs trombozu tespit edemedik. Subaraknoid hemorajinin nedeni Behçet hastalığının vasküler yapılarda geliştirdiği inflamasyona bağlı olabilir.…”