PRES+RCVS可逆性脑后部综合征和可逆性脑血管收缩综合征
可逆性脑血管收缩综合征临床表现、影像学特征及鉴别诊断.

可逆性脑血管收缩综合征临床表现、影像学特征及鉴别诊断可逆性脑血管收缩综合征是一类较为罕见的脑血管疾病,其特点是大脑中动脉狭窄和扩张可逆性变化,临床表现为严重的头痛、癫痫发作或局灶性神经功能障碍。
常见临床症状霹雳性头痛。
RCVS的主要临床表现为突发剧烈的霹雳性头痛,通常在数秒内达到高峰,持续数天至数周。
头痛发作呈弥漫性,可能位于枕部或顶部,患者常伴有恶心和对光敏感。
虽然大多数患者在数分钟至数小时内疼痛有中等程度的缓解,但接下来仍可能出现突发的严重头痛发作,持续数日。
诱因。
许多RCVS患者的发病与特定诱因有关,如体力活动、急性应激或情绪化状态、Valsalva动作(如用力、咳嗽和打喷嚏)、沐浴和游泳等。
这些诱因可能加重患者的症状,导致病情恶化。
血压。
患者初始血压可能会升高,这可能是由于剧烈头痛、疾病本身或相关因素引起的,对患者的血压进行监测和控制是治疗过程中的重要环节。
神经系统受累。
尽管头痛仍是许多RCVS唯一症状,部分患者可能因基础缺血性脑卒中、脑内出血或可逆性脑水肿而出现局灶性神经功能障碍。
患者可能表现为偏瘫、震颤、反射亢进、共济失调和失语等症状。
视觉障碍也较常见,包括暗点、视物模糊、偏盲和皮质盲等。
影像学特征初始神经影像学检查:在出现广泛脑血管收缩的RCVS患者中,约30%-70%的初始神经影像学检查可能未见异常。
然而,大约75%的住院患者最终会出现脑实质病变。
最常见的病变包括缺血性脑卒中和皮质表面(凸面)非动脉瘤性蛛网膜下腔出血,其次是可逆性血管源性脑水肿和脑实质出血。
图1. RCVS的各类初始神经影像学特点注:(A) 头颅CT血管造影:显示双侧前脑动脉呈经典“香肠串”形态的矢状最大密度投影图像。
(B) 头颅CT:轴向图像显示右额叶上覆盖的蛛网膜下出血(箭头)。
(C) 脑MRI:同一患者的轴向FLAIR图像显示右额蛛网膜下出血(箭头)以及双半球脑沟内的多个点状高信号(箭头),提示扩张的皮质表面动脉存在。
神经影像:可逆性后部脑病综合征(PRES)

• PRES的病理生理机制主要为急剧升高的血压超过了脑血流自身 调节上限,导致脑高灌注。、
• 动脉血压急剧升高,自身调节反应失效,引起大脑高灌注,血 脑屏障破坏,致血浆和大分子物质溢出到组织间隙。大脑后部 对高灌注尤其敏感,因为后颅窝交感神经较少。在部分易感患 者中,即使血压没有超过典型的自身调节范围,也可以导致内 皮细胞功能受损和血脑屏障破坏。因此,患者的基础血压、血 压升高幅度和升高速度是重要影响因素。
• 除外血压急剧升高,循环细胞因子过载也可能会引起内皮细胞 功能异常。在炎症反应中,淋巴细胞和单核细胞的激活导致细 胞因子释放(如TNFα、IL-1、IFNγ)。这些细胞因子激活内 皮细胞分泌血管活性物质,增加血管通透性,导致大脑间质水 肿。TNFα和IL-1诱导粘附分子的表达(如细胞间粘附分子1 [ICAM-1]、血管细胞黏附蛋白1[VCAM-1]、E选择素等)。 TNFα诱导血管内皮生长因子(VEGF)的表达,后者可以增加 血管通透性。PRES患者免疫系统激活,也会释放细胞因子,上 调VEGF的表达。子痫前期和子痫患者血VEGF-A升高,与PRES显 著相关。
表: PRES常见临床症状
临床症状 脑病 癫痫发作 头痛 视觉障碍 局灶性神经功能缺损 癫痫持续状态
发生率(%) 50-80 60-75 50 33 10-15 5-15
• 颅脑影像学有助于诊断PRES以及鉴别诊断。血管源性水肿可以 通过CT来发现,但颅脑MRI更敏感。由于缺乏诊断金标准,无 法评估MRI的特异性。颅脑MRI典型表现为双侧顶枕叶为主的血 管源性水肿,呈T1低信号,T2/FLAIR高信号,DWI等或低信号 ,ADC高信号。通常累及皮质下白质,较少累及皮来自。水肿几 乎累及双侧,不完全对称。
• 其它常见的症状包括头痛和视觉障碍(视力下降、视野丧失、 皮质盲和幻觉)。头痛常表现为钝痛,呈弥漫性,逐渐起病。 雷击样头痛患者需怀疑脑血管收缩相关疾病,建议行脑血管造 影。局灶性神经功能缺失,如偏瘫或失语,见于5-15%的患者 。脊髓受累引起脊髓症状和体征者极少见,但仍有个案报道。
可逆性后部脑病综合征

Imaging Patterns影像表现
病灶主要出现在双侧顶叶后部及枕叶, 且多为基本对称的病灶,偶尔可出现在 额叶后部、颞叶后部及小脑半球;也可 累及基底节、 脑干。病灶主要累及皮质 脑回或皮质和皮质下白质同时累及。
RPES在MRI上病灶显示更清晰,表现为 T1WI低信号、T2WI高信号,尤其在
FLAIR上显示清楚,表现为高信号, 这些都提示病灶内含水增多。
病灶可以发展。
DWI提示血管源性水肿,水肿最终可 以完全消失。
11%–26%出现细胞毒性水肿,说明有 脑梗死或即将发生脑梗死,提示预后不 佳。
15% 病人出现血肿或蛛网膜下腔出血, 提示预后不佳。
FLAIR
增强扫描
A–E, 双侧额叶、顶叶、枕叶广泛、对称分布的 高信号,以皮层为主,未见明显强化。
高血压脑病
FLAIR
Fig 7. 68岁,女,坏死性胰腺 炎, 胰周脓肿. 脓液培养凝固酶 阴性葡萄球菌、鲍氏不动杆菌 阳性,7天后神经精神症状加 重,发病血压(168/68 mm Hg),基础血压 (141/67 mm Hg)。
A-B, FLAIR 双侧顶叶、枕叶 对称高信号。 C-D, 1 月后,病灶大部分消 失.
FLAIR
A–C, FLAIR 双侧额叶、 顶叶皮层高信号。
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Fig 5. 20岁,女,高危妊娠,发生先兆 子痫,妊娠33 周,出现头痛、视力模糊、 轻微高血压 (156/106 mm Hg) 。
可逆性后部脑病的影像诊断与鉴别诊断

PRES可逆性后部脑病的影像诊断与鉴别诊断概述PRES影像表现鉴别诊断小结概述•PRES:一种可逆性神经系统损伤和特异性影像学表现为主的临床影像学综合症。
•所有人群都可发病,女性多见,儿童也可发病。
•急性-亚急性,雷击样头痛。
•儿童的临床表现多与成人相仿,影像表现多不典型。
临床特征•癫痫多为首发症状。
•视觉异常:视野受损、模糊、幻觉,皮质盲、矢认症、安东综合征。
•精神异常:躁动、不安、淡漠。
•少见表现:小脑综合征、偏瘫。
•CSF:多为正常,可有蛋白的升高。
•EEG:慢波、癫痫改变。
•LDH:升高,提示有内皮细胞损伤。
•高血压急症。
•子痫及子痫前期。
•严重的肾脏疾病。
•自身免疫性疾病。
•使用免疫抑制药物/细胞毒性药物。
发病机制•血压快速增高及高灌注。
•内皮细胞受损。
•血管痉挛继发缺血。
发病机制治疗•高血压:纠正高血压到可控范围,但是要避免降压过快导致缺血。
•子痫前期:目标是在分娩时的血压管理,硫酸镁防止癫痫发作。
•药物导致:逐渐缩小或完全停药。
•低镁血症可能示PRES的病因,因此推荐补充镁作为辅助治疗。
•可复发:在血压未控制好、或者需要继续用药的病人。
影像特点部位:•典型:顶枕叶。
•不典型:额叶、颞叶、小脑、脑干、基底节、深部白质、胼胝体、脊髓。
分布: •双侧对称。
•白质较灰质明显。
影像表现:•典型:血管源性水肿。
•不典型 :出血(5-30%)、强化、弥散受限(11-26%)。
典型影像表现-CT•平扫:双侧顶枕叶斑片状低密度影。
•血管造影:不规则局部或血管多发狭窄(串珠征)、局部血管扩张,最常见于主干和二级分支。
典型影像表现-CT34岁 女 急性淋巴性白血病化疗 甲氨喋呤鞘内注射 出现右侧偏瘫 收缩压200mmHg 串珠征(箭头)血管局部扩张(箭号)24 男坏死性肺炎典型影像表现-MRI•等-稍长T1、长T2信号。
•FLAIR呈高信号。
•DWI呈等高信号、ADC呈高信号。
•MRS:Cho、Cr升高;NAA、NAA/Cr减低;乳酸增加提示缺血。
可逆性后部白质脑病

血管痉挛、通透性增加,导致影像学上的 病理改变。当血管形态恢复正常后,影像
国际头痛协会提出的RCVS 诊断标准
①急性严重性头痛(多为雷击样头痛)伴或不 伴局灶神经功能缺损或癫痛发作; ②单相病程,1个月后不出现新的症状;
③血管成像(MRA , CTA或DSA)证实存在
可逆性脑血管收缩综合征:
(Reversible cerebral vasoconstriction syndrcme,RCVS) 是一组相对少见的临床一影像综合 征,主要临床特点为突发雷击样头痛, 伴或不伴局灶神经功能缺损及癫痛发作,
鉴别诊断
RCVS 与 PRES 的临床症状与体征、
影像学特征存在相似之处。
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神经影像:可逆性后部脑病综合征(PRES)PPT

常见的体征包括视力障碍、偏瘫、偏 盲等,部分患者可能出现病理征阳性。
02
PRES的神经影像学表现
常规MRI表现
01
02
03
脑水肿
在MRI的T2加权图像上, PRES通常表现为脑后部白 质的高信号,尤其是顶枕 叶和枕叶区域。
血管源性水肿
PRES患者还可能出现脑实 质的血管源性水肿,这通 常在MRI的T2加权图像上 表现为高信号。
在MRS(磁共振波谱)上,PRES患者的NAA水平通常降低,这表明神经元功能受 损。
肌酸(Cr)水平升高
同时,PRES患者的Cr水平通常升高,这可能反映了一种代偿机制或细胞内环境 的紊乱。
03
PRES与其他疾病的鉴别诊断
与急性脑卒中的鉴别诊断
急性脑卒中通常表现为脑部血管阻塞或破裂,导致脑组织缺血或出血。PRES通常表 现为大脑后部白质和灰质区域的对称性水肿。
急性脑卒中通常伴随其他神经系统症状,如偏瘫、失语等,而PRES可能仅表现为头 痛、癫痫发作和视觉障碍。
急性脑卒中的神经影像通常显示脑部血管阻塞或出血的证据,而PRES的神经影像显 示大脑后部水肿。
与脑部肿瘤的鉴别诊断
01
脑部肿瘤通常表现为颅内占位性病变,压迫周围脑组织,导致相应的神经功能 障碍。PRES则表现为大脑后部水肿,无占位性病变。
PRES有所不同。
缺氧性脑病通常表现为大脑 皮质和白质广泛水肿,伴随 意识障碍和神经系统症状。 代谢性脑病则根据具体病因
有不同的表现。
其他可逆性脑病的神经影像 显示相应区域的水肿,需要 结合病史和实验室检查结果 进行鉴别诊断。
04
PRES的治疗和预后
病因治疗
控制高血压
高血压是PRES的主要病因之一,控制血压是预防 PRES复发的关键措施。
可逆性脑血管收缩综合征

可逆性脑血管收缩综合征转载自:神经病学医学网一本神经的神经作者:秦伟教授可逆性脑血管收缩综合征(RCVS)在临床上并不罕见,但存在认识不足。
临床中也遇到了这种病例,从怀疑是这个病到找到诊断证据,颇费了一番周折,又想起之前会诊的1例产后多次剧烈头痛的患者,当时脑CT及MRI都是正常的,查到当时的MRA,确信也是RCVS。
看来这个综合征并不少见,查阅了一些资料,做成幻灯,分享给大家!该课件主要基于相关的英文文献,精力有限,错误难免,内容较为粗糙,也未能解释清楚大家普遍有困惑的地方,见谅!——秦伟以上五个病例均来自文献,这些疾病的共同表现就是可逆的颅内动脉多发节段性狭窄。
由此,引出我们将要谈及的内容,RCVSLancet Neurology 2012年一篇综述的摘要,总结了该综合征的情况RCVS于2007年以后才广泛应用,之前有各种称呼,从表现上,都是RCVS该综合征主要以霹雳头痛起病,多有触发因素,有诱因,多次发作,不同时期有不同的并发症,为动态的病程脑组织影像所见就是PRES该例病例更像PRES而非RCVS,未有血管证实,作者认为还是RCVS高分辨核磁的血管壁成像对该病和PACNS的鉴别有重要作用早期的征象可合并存在其他颅内病变常见的影像技术均能用到,复查很重要可能的发病机制,血脑屏障破坏是近期提出的目前的诊断标准一般参考2007年提出的结合该综合征的临床表现,要鉴别霹雳头痛、SAH等该综合征与颈部动脉夹层和偏头痛关系较为密切血管影像学上主要与PACNA鉴别该综合征与PRES的关系,很密切,但是具体的鉴别点没找到1篇妊娠和产后神经急症的综述对产后RCVS和PRES的不同进行了对比,可以参考治疗包括一般处理、对症、药物治疗等预后较好一篇病例报道总结的诊断流程,可资参考,实际工作中,考虑的要比这复杂其实该综合征也很简单,总结起来,就一张表:临床上一是想不到,二是想到了有时不好证实开头提到的病例都是RCVS。
可逆性后部脑病综合征(PRES)的影像学表现

可逆性后部脑病综合征(PRES)的影像学表现病史患者女,19岁,患者于昨日出现头晕伴头痛、鼻塞、流涕、咳嗽,无发热,无胸痛,故来我院就诊。
体格检查:神清,咽后壁充血明显,两肺呼吸音粗,未闻及啰音,心律齐,腹平软,无压痛及反跳痛,双下肢不肿。
辅助检查两侧枕叶、额顶叶及右侧基底节区见多发斑片状、结节状异常信号T1WI上呈等、稍低信号,T2WI及T2 FLAIR上呈高信号,DWI上为等、稍高信号,以大脑皮层累及为主。
脑室、脑池系统形态、大小及位置未见异常改变。
脑沟未见明显增宽。
中线结构居中。
▶诊断思路:可逆性后部脑病综合征(PRES)是一种以抽搐、头痛、意识障碍和视物模糊为常见临床症状,以双侧人脑半球后部白质区异常信号为影像学主要表现的综合征。
早期诊断和及时治疗是可逆性恢复的关键。
对于PRES的病因,多数学者认为与多种l临床疾病有关“。
,主要包括高血压病、妊娠子痫、慢性肾功能不全、恶性肿瘤化疗、接受免疫抑制和细胞毒性药物治疗等。
发病机制:目前多数学者认为PRES主要病理改变为血管源性脑水肿.已提出高血流灌注学说、交感神经缺乏学说和血管内皮细胞损伤学说。
高血流灌注学说认为当血压骤升时,大脑处于高血流灌注状态。
超过大脑血管自身调节能力的极限,导致血管扩张、血脑屏障破坏,易出现血管源性脑水肿。
严重时前循环系统的微血管也会出现类似的改变。
累及脑深部核团、额叶、小脑甚至脑干。
交感神经缺乏学说认为脑后部白质最易受累是由于该部位由椎基底动脉系统的后循环系统供血,相对前循环颈内动脉系统缺少丰富的交感神经支配。
导致血压突然升高时后部脑血管对维持和调节血管张力失常,更易渗透性增加和血管源性水肿。
血管内皮细胞损伤学说认为结缔组织病变等产牛的循环系统内细胞毒素及抗血管内皮细胞抗体引起血管内皮细胞破坏,导致血管源性水肿。
免疫抑制和细胞毒性药物引起PRES的机制可能与药物的直接毒性作用有关。
影像学表现:PRES最突出的影像学表现为双侧大脑半球后部广泛性白质异常。
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Clinical Reasoning:A 33-year-old woman with severe postpartum occipital headachesNancy Maalouf,MD Sami I.Harik,MDSECTION 1A 33-year-old woman with history of occasional “migraines”complained of severe occipital head-ache,following an uncomplicated full-term vagi-nal delivery under epidural anesthesia.This headache was qualitatively and quantitatively dif-ferent from her usual headaches.The diagnosis of low intracranial pressure headache related to inad-vertent dural puncture was considered and 2epi-dural autologous blood patches were performed with no relief.One week postpartum she pre-sented to an outside hospital with complaints of poor concentration,difficulty in finding words,getting dressed,and feeding herself,and left arm numbness.Examination showed a blood pressure of 179/119mm Hg,poor attention span,apraxia,and decreased sensation in the left hand.General physical examination was unrevealing.Head MRI (day 0)showed fluid-attenuated in-version recovery (FLAIR)hyperintensities (figure 1,A and B)and diffusion restriction with positive apparent diffusion coefficient (ADC)map (figure 1,C and D)in the right parietal lobe and in the splenium of the corpus callosum.The diagnosis of posterior reversible encephalopathy syndromeUpper panel MRI,performed on admission,showed FLAIR hyperintensities and diffusion restriction in the right parietal lobe and in the splenium of the corpus callosum (arrows).Lower panel,done on hospital day 3when the patient deteriorated,showed worsening lesions involving the cortex and subcortical white matter of the parietal,posterior frontal,and occipital lobes,bilaterally (arrows).From theUniversity of Arkansas for Medical Sciences,Little Rock,AR.Disclosure:The authors report no disclosures.Correspondence &reprint requests to Dr.Maalouf:maaloufnancy@RESIDENT &FELLOW SECTIONSection EditorMitchell S.V.Elkind,MD,MS(PRES)was entertained and the patient was treated for that condition with the antihyperten-sive agents nifedipine and lisinopril.The patient’s condition deteriorated.On the third hospital day,she became cortically blind and mute,and had motor perseverations and left-sided weakness. Repeat head MRI showed marked worsening with lesions involving the cortex and subcortical white matter of the parietal,posterior frontal,and occipital lobes,bilaterally(figure1,bottom panel).Question for consideration:1.What is the differential diagnosis?SECTION2The differential diagnosis of multifocal infarcts in the distribution of many vascular territories is wide.It in-cludes emboli from heart and aorta,disseminated intra-vascular coagulopathy,thrombotic thrombocytopenic purpura,moyamoya disease,vasculitis secondary to connective tissue and autoimmune systemic diseases,or viral/bacterial/fungal infections.Another possible rare entity is primary CNS angiitis.The presentation of this patient with postpartum headache,elevated blood pres-sure,and focal neurologic deficits suggested the diagno-sis of PRES to the treating neurologist.The sudden occurrence of severe headache in a young woman postpartum should also raise concern for sentinel headaches and subarachnoid hemorrhage because of their considerable morbidity and mortal-ity and because they are eminently treatable if diag-nosed early.These headaches are usually explosive, reach maximum intensity within minutes,and can last for hours to days.Subarachnoid hemorrhage is usually associated with symptoms and signs of men-ingeal irritation,altered consciousness,and focal neurologic signs.The presence of these signs in a peripartum woman should also raise the possibility of cerebral venous sinus thrombosis.Although these headaches commonly have a subacute onset,they might have a more acute presentation during puerpe-rium.Pituitary apoplexy occurs as well in association with late pregnancy,presenting with acute headache, nausea,decreased visual acuity,ophthalmoplegia, and visual field defects.Question for consideration:1.What studies/tests should be performed?SECTION3In the outside hospital,head magnetic resonance (MR)venography was unrevealing.EEG showed mild diffuse slowing.Lumbar puncture yielded clear CSF that was acellular with normal glucose and pro-tein content.Bacterial and fungal cultures,crypto-coccal antigen,herpes simplex virus PCR,VDRL, and cytology were all negative.Because of clinical deterioration,the patient was transferred to our university hospital where a head CT angiography(CTA)revealed segmental narrowing of many intracranial vessels but primarily involving the vertebral,basilar,posterior,and middle cerebral arteries (figure2,A and B).Transcranial sonography measured increased flow velocities in right middle(170cm/s), right posterior(230cm/s),left middle(130cm/s),and left posterior(140cm/s)cerebral arteries.Vasculitis workup including erythrocyte sedimentation rate,C-reactive protein,rheumatoid factor,antinuclear antibody,anti-neutrophil cytoplasmic antibody,double-stranded DNA,anti-SSA/Ro,anti-SSB/La antibodies,cryoglob-ulin,and angiotensin-converting enzyme was negative.Based on the above,reversible cerebral vasocon-striction syndrome(RCVS)was suspected.The pa-tient was treated with oral nimodipine,60mg every 4hours;aspirin,81mg daily;and methylpred-nisolone,125mg IV every6hours for6days before the results of the vasculitis workup became available. The patient gradually improved:she became more alert but remained apathetic with partial expressive aphasia,apraxia,and perseveration.She perceived light and shades but her visual acuity remained below 20/200.She also had residual mild left hemiparesis with diffuse hyperreflexia and bilateral ankle clonus. Nimodipine was gradually tapered after10days and she was transferred to a rehabilitation facility.Follow-up at2months after discharge showed her to be alert,with near-normal visual acuity(20/25) and intact color vision.She had residual right inferior quadrantanopia,apraxia,mild left hand weakness, and diffuse hyperreflexia.Head MRI showed evi-dence of encephalomalacia in the frontoparietal lobes,left occipital lobe,and splenium of the corpus callosum.Head MR angiography revealed completeresolution of the previously noted vasoconstriction (figure 2,C and D).DISCUSSIONThe most important information re-garding the diagnosis and treatment of this patient was obtained before transfer to our hospital.The findings of positive diffusion-weighted imaging and ADC map in the right parietal lobe and splenium of the corpus callosum was indicative of ischemic stroke which is rarely seen in PRES.1The clinical and MRI worsening after antihypertensive treatment makes the diagnosis of ischemic strokes more convincing.What is the cause of cerebral ischemia?She had no clinical evidence of heart disease.CTA ruled out moyamoya and premature atherosclerosis,and clearly revealed segmental narrowing of large and medium-sized arteries at the base of the brain,highly suggestive of RCVS.RCVS refers to a group of disorders sharing an-giographic and clinical features including reversible segmental and multifocal vasoconstriction of cerebral arteries,and sudden severe headaches with or with-out focal neurologic deficits or seizures.These disor-ders were previously reported as Call-Fleming syndrome,benign angiopathy of the nervous system,and postpartum angiopathy.2The pathophysiology of RCVS remains unknown,though transient distur-bance in the control of cerebral vascular tone was hypothesized.3There is gender preponderance of RCVS in women.Half of the patients give history of mi-graine.2The condition is idiopathic or related to a number of factors,including late pregnancy/post-partum and use of vasoactive substances such as triptans,selective serotonin reuptake inhibitors,pseudoephedrine,cannabinoids,cocaine,amphet-amines,methylenedioxymethamphetamine (ecstasy),bromocriptine,and nasal decongestants.4Postpar-tum angiopathy is an extremely rare complication that usually occurs in a normal pregnancy,as was the case in our patient.Two-thirds of those patients pres-ent in the first postpartum week.5In 50%–70%of cases,it is associated with the use of vasoconstrictors,mostly ergots,to treat postpartum hemorrhage or to inhibit lactation.Intracranial hypotension,whether spontaneous 6or secondary to dural puncture,7was also reported as a possible etiology of RCVS.The diagnosis of RCVS is usually made on ce-rebral arterial imaging which shows diffuse and multifocal segmental narrowing of large and medium-sized arteries.The anterior and posterior brain circulations are involved.Occasional dilated segments,like strings and beads or sausage strings,were described.The diagnosis is confirmed only by documenting reversal of the vasoconstriction within few months.2Vasoactive medications should be stopped.Clini-cal and angiographic resolution occurs spontane-ously;however,calcium channel blockers like nimodipine are used with variable success.Long-term measures include secondary stroke prevention and treatment of complications.6–8A short course of steroids may be justified to cover for cerebral vasculi-tis while awaiting results of workup,although a re-cent retrospective case-series study found worse outcome in patients who received steroids.However,this matter is confounded by the possibility that ste-roids were administered to sicker patients.9The clinical outcome is usually good,with most patients recovering completely within days to weeks.The major complications of RCVS are localized cor-tical subarachnoid hemorrhages (20%–25%of cases)and ischemic strokes (5%–10%).5Hemorrhagic complications and seizures occur earlier (within the first 10days)compared to ischemic events (around 12days from headache onset).2Association with PRES 7and recurrence 10were reported.Patients with severe new-onset headache and focal neurologic deficits must be assessed urgently and sev-eral diagnoses must be considered.Initial diagnosticHead CTA at day 6reveals segmental narrowing of the left middle cerebral artery and the A1segment of the right anterior cerebral artery (A,arrows);segmental narrowing of the posterior cerebral and left distal vertebral arteries with broad narrowing of the basilar ar-tery (B,arrows).Head MRA 2months after discharge shows complete reversal of arterial pathology (C and D).The magnification is similar in all parts of the figure;the white vertical band denotes 5cm.studies should include an unenhanced head CT and lumbar puncture.If both studies are normal,head MRI,MR angiography of the head and neck,and MR venography are necessary.When this workup reveals segmental vasoconstriction,normal or near normal CSF studies,and a lack of any other underly-ing pathology,RCVS should be considered.In the case we presented,PRES was initially suspected,so blood pressure was aggressively controlled,which worsened brain ischemia.Thus,antihypertensive agents should be used with caution in RCVS,just like any other condition causing ischemic strokes.AUTHOR CONTRIBUTIONSDr.Maalouf:drafting/revising the manuscript,study concept or design, analysis or interpretation of data.Dr.Harik:drafting/revising the manu-script,study concept or design,analysis or interpretation of data.REFERENCES1.Finocchi V,Bozzao A,Bonamini M,et al.Magnetic reso-nance imaging in Posterior Reversible Encephalopathy Syndrome:report of three cases and review of literature.Arch Gynecol Obstet2005;271:79–85.2.Ducros A,Boukobza M,Porcher R,Sarov M,Valade D,Bousser MG.The clinical and radiological spectrum ofreversible cerebral vasoconstriction syndrome:a prospec-tive series of67patients.Brain2007;130:3091–3101. 3.Schwedt TJ,Matharu MS,Dodick DW.Thunderclapncet 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