颅脑外伤的CT诊断改

颅脑外伤的CT诊断,1,一、头皮,（一）解剖层次 颞部 穹窿部 皮肤 皮肤 皮下 皮下 颞浅筋膜 颞深筋膜 颈肌 颅顶肌和帽状腱膜 帽状腱膜下脂肪组织 骨膜 骨膜,2,3,（二）头皮外伤血肿 皮下 头皮血管 帽状腱膜下 由于 硬膜血管 破裂 骨膜下 板障静脉擦伤挫伤裂伤挫裂伤,4,二、颅骨骨折,5,（一）分类发生部位 颅盖 颅底骨折线形态 线样 凹陷样 粉碎性 穿透性与外界关系 闭合性 开放性,6,（二）表现1、颅盖骨折颅缝分离： 2mm；不对称线样： 并血肿凹陷性： 并颅板内陷（儿童：乒乓球）；并血肿粉碎性： 并血肿-大的暴力穿通、开放性（硬膜）、穿孔（一次、二次）： 为锐器伤，并： 头皮破裂、头皮血肿 硬膜外、硬膜下血肿、蛛网膜下腔出血、气颅 脑挫裂伤，脑内血肿 颅内外异物,7,鉴别 板障静脉 不规则 对侧可见 终于静脉湖 血管沟 渐细 硬化边 颅骨内板 骨缝 走行部位固定 两侧对称,8,2、颅底骨折（1）特点常合并颅盖骨折多呈线形常通过薄弱处在前后颅凹，纵行；在中颅凹，横行不常合并颅内血肿,9,（2）征象1）直接：骨折线颅缝分离2）间接：气颅鼻窦可见液气、混浊脑脊液鼻漏（筛骨）,10,11,Skull Fractures,Linear fractures： CT is not good for linear fractures，always need bone window to evaluateDepression fracture. CT is important for the depression of fracture and other associated interacranial lesions.,12,Head injury with fractures，scalp hemorrhage，countre-coup acute subdural hematoma，uncal/tentorial herniation,三、颅内脑外积聚物-血肿、积液、积气,13,包括硬膜外腔 硬膜下腔 蛛网膜下腔 主要相关于硬脑膜软脑膜蛛网膜,14,二、Epidural lesionsEpidural hematomasubdural hematomasubdural effusion,（一）硬膜外血肿,15,1、特点急范围局限脑组织可受压；中线结构移位不明显并发骨折位于脑膜动脉区颞区多见,16,2. CT表现梭形高密度急性：密度均匀； 慢性：密度不均-活动性出血或再出血内缘光滑范围局限，不越颅缝但可越中线或小脑幕占位效应小，中线移位轻并骨折包膜钙化或骨化,17,18,19,Acute Epidural Hematoma,Fusiform shape（纺锤体） of hyperdense lesion. Always causing strong mass effect.,20,Acute Epidural Hematoma,The hematoma still contains uncoagualated blood, or still has active bleeding. Round,stream-like filling defects may be seen in the hematoma.,21,male/16,delayed EDH,and sportaneous resorption,88,3,28 Head injurypatient was irritable,88,4,15 A subacuteepidural hematoma,88,5,18 No surgeryThe EDH is small,1、急性硬膜下血肿,22,（1）分型单纯型-矢状窦旁顶部桥静脉 静脉窦 皮层静脉 动脉复合型-脑挫裂伤引起 皮层静脉或动脉出血破入硬膜下腔 与冲击部位有关,23,（2）典型 CT表现高密度密度均匀范围广颅骨内板下方-新月形或“3”形（侧裂处） 位于大脑镰旁、小脑幕旁-带状范围局限，不越颅缝但可越中线或小脑幕占位效应-同侧侧脑室变窄 中线移位明显复合型-与脑内血肿联接,24,（3）非典型 CT表现 表现 原因密度不均 未凝、血清外溢 脑脊液漏入梭形 活动性出血 没有及时散开同侧侧脑室扩张 室间孔受压受阻,25,Sickle-shape（镰刀型）or new lunar shape（新月形）of hyperdense lesion over large portion hemisphere,Acute Subdural Hematoma,26,Acute Subdural Hematoma with mass effect,A.Acute subdural hematoma with mass effect B.Post-craniotomy,the SDH was removed,the mass effect,27,The hematoma may extending into the subdural space of tentorial region,Acute Subdural Hematoma,28,29,30,31,The hematoma may extending into the interhemispheric fissure orAn acute SDHlocatesin theinterhemisphericfissure,Acute Subdural Hematoma,32,The hematoma may extending into the subdural space of tentorial region,Acute Subdural Hematoma,33,34,The lesion is in the opposite side of impact site. 30 incidence.,Counter-coup Injury,fracture,Scalp,35,Contusion hemorrhage with some SAH,Head injury with delayed SDH,EDH,The same day,12 hours later:acute SDH and EDH,36,A.Brain atrophy with mild hydrocephalusB.VP shunt,acute SDHs,both sidesC. The acute SDH enlarged in right side,VP shunting induces acute subdural hematoma,2、亚急性硬膜下血肿-4天3周,37,（1）早期：高与低密度液面或混杂密度-细胞沉淀 上浮血清-蛋白 沉淀细胞-继续出血、再出血、凝血异常（2）晚期：等或低密度等密度硬膜下血肿：白质受压内移，灰白质结合部远离颅骨内板皮层静脉移位中线移位脑室变形增强扫描：皮层染色内移,38,3、慢性硬膜下血肿-3周以上,39,（1）病理：包膜形成包膜血管血浆渗入 高渗蛛网膜下腔血肿增大梭形血肿液化蛋白分解 脑脊液渗入血肿壁玻璃样变性、钙化血肿包裹粘连机化多腔（2）CT表现梭形、新月形、“3”字形低密度或混杂密度-有否再次出血，血肿大小、溶解吸收 程度 脑脊液、血浆渗入多少,40,Shape: Semilunar, Fusiform Over shapeDensity: Hyperdense Isodense Hypodense Mixed density,Chronic Subdural Hematoma,41,Chronic subdural hematoma with mixed densities (isodense and hyperdense),Chronic Subdural Hematoma,Chronic subdural hematoma withfluid-blood level(rebleeding),42,Chronic Subdural Hematoma,43,44,45,（三）蛛网膜下腔出血,46,（1）病理多为对冲伤皮层静脉破裂血进入脑沟、脑池内 脑室内出血蛛网膜下腔 合并脑内血肿 软脑膜破裂 合并硬膜下血肿蛛网膜破裂（2）表现CT高密度，与出血量有关多见于脚间池、外侧裂池常在一周内消失,47,（四）脑室内出血,48,1、病理多数 脑内出血破入 脑室穿通伤 四脑室逆行的蛛网膜下腔出血 少数 室管膜下静脉破裂-单纯脑室出血凝结成块，侵入脑室后部、溶解2、表现CT1-2周呈高密度并发其它脑外伤改变继发脑积水,49,Often associated with other intracerebral or extracerebral lesions CT：Blood in the ventricles May cause acute obstructive or chronic communicating hydroceohalus,Traumatic IVH(Intraventricular Hemorrhage),（五）颅内积气,50,气颅-颅内外交通硬膜外腔 气体 硬膜下腔 蛛网膜下腔 密度 脑室内 脑内 影像,51,CT： Multiple air bubbles in the subarachnoid spaces Sources of air: 1.Open fracture of the cranium 2.Skull base fracture,air from the paranasal sinuses or mastoid,Traumatic Pneumoencephalus,四、原发脑损伤,52,脑挫伤/脑裂伤/脑挫裂伤/脑内血肿 穿通伤脑白质剪切伤脑干损伤脑肿胀、脑水肿,（一）脑挫伤/脑裂伤/脑挫裂伤/脑内血肿,53,1、脑挫伤/脑裂伤/脑挫裂伤（1）病理脑挫伤 脑内散在出血灶 静脉淤血 脑水肿和脑肿胀 脑裂伤 上述改变伴脑膜、脑或血管断裂两者常合并存在，同称,54,（2）CT表现脑水肿-低密度，可局限性或广泛性脑出血-高密度，可散在点状分布或广泛性可合并蛛网膜下腔出血或硬膜下血肿,55,2、脑内血肿（1）病理多发于额颞叶位于受力点或对冲部位脑表面演变：急性期吸收期囊变期（2）CT表现密度： 高低囊水肿： 轻重无皮层下区占位效应： 正负,56,（二）穿通伤异物出血肿胀（三）脑白质剪切伤灰白质受剪切力作用轴突损伤 伴行血管破裂出血中央、周边灰白交界、胼胝体、大脑脚 多发少量出血,57,（四）脑干损伤剪切伤脑肿胀/脑水肿（五）脑白质剪切伤脑室小 脑沟脑池消失 灰白质界限消失中线移位脑组织密度减低脑疝,58,1.Circumscribed area of brain edema2.Brain edema mixed with multiple small hemorrhages3.A solitary hematoma4.Diffuse brain edema5.Diffuse axonal injury (shearing injury),Brain Contusion,59,Delayed hemorrhage,several hours or days afterhead injury,Delayed Hemorrhage,soon after head injury,8 hours later,60,Head injury with EDH and delayed contusion hemorrhages,june 22,june 20,61,62,63,64,65,同侧撞击同侧出血,66,When clinical symptom is grave,but the CTfinds no serious injury,DAI shuold be considered CT findings:(positive under 20) Punctate hemorrhages or edema in the carpus callosum,centrum semiovale,basal ganglion brainstem,Diffuse Axonal Injury(DAI)(Shearing Injury),67,Coma after head injury4 months later,semi-vegetate stage,4 months later-brain atrophy,5th dayMultiple punctate hemorrhages,Diffuse Axonal Injury(DAI),1st day,68,Punctate hemorrhages and edemas in the subcortical white matter of left frontal lobe(A) and carpus callosum (B,C),Head injury,GCS:3Diffuse Axonal Injury(DAI),五、脑血管损伤,69,脑梗塞 压迫 痉挛 脂肪栓塞 血管壁剥离 低氧血症假性动脉瘤动静脉瘘静脉栓塞,五、脑血管损伤,70,（一）正常颅腔颅骨 多个腔 承托 脑组织 硬膜 压力平衡 固定、保护 （二）占位病变 一腔脑组织 压力失衡某一孔道 脑疝 另一腔中,71,（三）表现脑池被脑组织填充正常结构移位