中腦周圍非動(dòng)脈瘤性蛛網(wǎng)膜下腔出血（Perimesencephalic

Nonaneurysmal

Subarachnoid

Hemorrhage）浙醫(yī)二院神經(jīng)內(nèi)科樓敏Concept定義:A.出血的中心位于腦干前緣（主要在腳間池），伴或不伴擴(kuò)展。B.動(dòng)脈造影未見動(dòng)脈瘤或其他動(dòng)脈異常vanGijn,etal.,In1985首先提出

Incidence動(dòng)脈造影陰性的SAH中，21-68%診斷為PNSH在非動(dòng)脈瘤和動(dòng)靜脈畸形的自發(fā)性SAH中，占8-11%動(dòng)脈造影陰性的SAH（15-20%）：未被發(fā)現(xiàn)的腦動(dòng)脈瘤非腦動(dòng)脈瘤性，如：靜脈血栓形成、血液病、感染、腫瘤EtiologyThecausehasnotbeenestablished.靜脈出血：發(fā)現(xiàn)了更多的靜脈結(jié)構(gòu)的異常假設(shè)2.腦干的小穿通動(dòng)脈閉塞后的繼發(fā)滲血肯定的是：高血壓、吸煙是其可控制的危險(xiǎn)因素ClinicalcourseSymptom:1.頭痛進(jìn)展較慢2.極少伴意識障礙3.臨床癥狀較輕（Hunt–Hess分級?~Ⅱ）Complication:1.幾乎不會再次出血2.較少血管痙攣（1-5%）3.腦積水發(fā)生率約20%，但很少需做分流

CTscanningThecriteria（within3daysoftheonset）:centerofbleedinglocatedimmediatelyanteriortothemidbrain;(2)possibleextensionofbloodtotheposteriorpartoftheanteriorinterhemisphericfissure,butnotcompletefillingoftheanteriorinterhemisphericfissure;(3)extensionofbloodtothebasalpartofthesylvianfissureispermitted,butnotextensiontothelateralsylvianfissure;(4)sedimentationofsmallamountsofintraventricularbloodisallowed,butnotfrankintraventricularhemorrhage;(5)absenceofintracerebralhematomaDiagnosisClinicalcourseofSAH（出血時(shí)無昏迷，Hunt–Hess分級?~Ⅱ）CTscanning:perimesencephalicpatternofhemorrhagewithin3daysoftheonsetoftheSAHAngiography:normalDifferentiatediagnosisImportanceofdifferentiation

Prognosis:thefinaloutcomewastypicallyexc