Cerebral Embolism of Iodized Oil (Lipiodol) after Transcatheter Arterial Chemoembolization for Hepatocellular Carcinoma

Cerebral lipiodol embolism is a rare complication of transcatheter arterial chemoembolization (TACE). Its pathological mechanism remains ambiguous despite several investigations. In Case 1, a 67-year-old man with hepatocellular carcinoma (HCC) experienced neurological deficits soon after undergoing a fourth session of TACE. Computed tomography (CT) scan showed multiple hyperdense lesions along the gyrus of frontal lobes and in the subcortical white matter. Transcranial Doppler (TCD) and transesophageal echocardiogram performed during the intravenous injection of agitated saline documented the presence of a right-to-left shunt (RLS) by demonstrating microbubbles in the left middle cerebral artery and left atrium. In Case 2, a 63-year-old woman underwent a third TACE due to a large HCC. After the procedure, her mental status deteriorated. Brain CT showed multiple hyperdense lesions on the cerebral and cerebellar cortex. TCD with agitated saline showed multiple microembolic signals shortly after the injection of agitated saline. The risk of cerebral lipiodol embolism may increase with recurrence and progression of HCC in patients who have a pre-existing RLS in the heart or lung. A test for the detection of an RLS may be necessary to identify patients with a heightened risk of cerebral embolism when multiple TACE procedures are required. TACE for HCC can cause pulmonary embolism or infarction. ^1,2 However, cerebral lipiodol embolism is rare after TACE. There have been several reports of cerebral embolism after TACE, but their exact mechanism has not yet been fully elucidated. We report herein 2 patients who developed cerebral lipiodol embolism after undergoing multiple TACE procedures for remnant HCC through a pre-existing RLS.     

Importance of Jugular Valve Incompetence in Contrast Transcranial Doppler Ultrasonography for the Diagnosis of Patent Foramen Ovale

Transcranial Doppler (TCD) ultrasound with the intravenous injection of agitated saline as contrast (cTCD) is an effective method for detecting right-to-left intracardiac and extracardiac shunt (RLS); however, the sensitivity of cTCD in the diagnosis of RLS remains slightly less than that of transesophageal echocardiography, even in patients with adequate transtemporal ultrasonic bone windows. The authors present a case with cTCD underestimating RLS because of jugular valve incompetence in a 42-year-old man presenting with an episode of transient aphasia. Three weeks after transcatheter closure of a patent foramen ovale associated with an atrial septal aneurysm, he experienced 2 episodes of amaurosis fugax. Following a negative 45-minute embolus detection study with power M-mode TCD, the patient underwent a cTCD study with monitoring of the left middle cerebral artery (MCA), the anterior cerebral artery, and the submandibular extracranial internal carotid artery. A single microbubble (MB) was detected in the left MCA in only 1 of 5 studies; the remaining runs all failed to detect an RLS. Significant MB reflux was noted in the left internal jugular vein because of jugular valve incompetence. The authors conclude that incompetence of the jugular vein valve can result in a false negative cTCD study for RLS detection.     

Fatty cerebral embolism after lymphography

A 25 year-old man with Hodgkin's disease, presented a confusional state with choreatic movements, 1 hour after a lymphography. CT showed high density in the heads of both caudate nuclei, and in the cortex. The patient's state improved and he entirely recovered within 2 weeks, while CT returned to normal. No right-to-left shunt was demonstrated. The mechanisms of this infrequent complication of lymphography are discussed: exceeding filtration capacity of lung because of a too rapid administration of contrast or severe lung embolism? intracardiac right-to-left shunts? microscopic arteriovenous shunts in the lung? bad venous cerebral drainage consecutive to a vena cava superior syndrome?     

A child with Diamond-Blackfan anemia, methylenetetrahydrofolate reductase mutation, and perinatal stroke

Diamond-Blackfan anemia is a congenital hypoproliferative anemia known to be associated with diverse physical anomalies affecting the thumb, craniofacial bones, urogenital system, and heart; prematurity; and fetal demise. We report the case of a 16-month-old boy with Diamond-Blackfan anemia noted to have decreased use of his right side since birth. Magnetic resonance imaging demonstrated a large area of encephalomalacia in the left middle cerebral artery territory. Magnetic resonance angiography showed marked attenuation of the left middle cerebral artery, suggesting a remote thromboembolic event. The laboratory results were remarkable for a decreased hemogolobin of 9.5 g/dL and increased platelets of 591,000/microL. He was heterozygous for the methylenetetrahydrofolate reductase gene C677T mutation. An echocardiogram demonstrated a patent foramen ovale versus an atrial septal defect with left to right shunting. Perinatal stroke may be a rare complication of Diamond-Blackfan anemia in the setting of other risk factors.     

Simultaneously Occurring Ischemic Stroke,Leg Artery Occlusion,and Pulmonary Embolism Induced by a Uterine Myoma

ObjectivesParadoxical embolism from venous thrombosis through the patent foramen ovale is a rare but well-known cause of stroke in young adults. Here, we report a case of simultaneous middle cerebral artery infarction, multiple occlusions of the leg arteries, and pulmonary thromboembolism from the venous thrombus, all due to compression of the external iliac vein by a uterine leiomyoma.Materials and Methods (Case presentation)A 44-year-old woman presented with left hemiparesis and central-type left facial palsy. She denied a history of hypertension, diabetes mellitus, previous cerebral infarction, myocardial infarction, smoking, or oral contraceptive use. The patient recovered completely after injection of tissue plasminogen activator. Brain diffusion-weighted imaging showed an acute right middle cerebral artery infarction. Transcranial Doppler with saline agitation test revealed a right-to-left shunt, suggesting a patent foramen ovale. Chest computed tomography revealed multiple pulmonary thromboembolisms. Lower extremity sonography and lower extremity computed tomography revealed a multifocal thrombus in the major veins and arteries of the left leg. Moreover, a large uterine myoma compressing the left external iliac vein was noted on lower extremity computed tomography.ResultsAfter the treatment of pulmonary thromboembolism and venous thrombosis with rivaroxaban, surgical thrombectomy of the left popliteal artery, patent foramen ovale closure, and total hysterectomy were performed. Subsequently, she had no recurrent paradoxical embolism or pulmonary thromboembolism.ConclusionStructural abnormalities in the pelvic cavity are not commonly suspected as stroke etiology. However, examination of the pelvic cavity is advisable in young female stroke patients with pulmonary thromboembolism or other paradoxical embolisms.     

Contrast transcranial Doppler ultrasound in the detection of right-to-left shunts. Reproducibility, comparison of 2 agents, and distribution of microemboli

BACKGROUND AND PURPOSE: Cardiac right-to-left shunts can be identified by transcranial Doppler ultrasound (TCD) with the use of different contrast agents and by transesophageal echocardiography (TEE). Systematic data are available on neither the reproducibility of contrast TCD, the comparison of different contrast agents, nor the comparison of simultaneous bilateral to unilateral recordings. Furthermore, we assessed the side distribution of thus provoked artificial cardiac emboli. METHODS: Fifty-four patients were investigated by TEE and by bilateral TCD of the middle cerebral artery. The following protocol was performed twice: injection of 9 mL of agitated saline without Valsalva maneuver, injection of 9 mL of agitated saline with Valsalva maneuver, injection of 5 mL of a commercial galactose-based contrast agent without Valsalva maneuver, and injection of 5 mL of the galactose-based contrast agent with Valsalva maneuver. RESULTS: In 18 patients, a right-to-left shunt was demonstrated by TEE and contrast TCD (shunt positive). Twenty-nine patients were negative in both investigations, 1 was positive on TEE and negative on TCD, and 6 patients were only positive on TCD. Both bilateral and repeated recordings increased the sensitivity of contrast TCD. There was a symmetrical distribution of microembolic signals in the right and left middle cerebral artery. CONCLUSIONS: TCD performed twice and with the use of saline or a galactose-based contrast agent is a sensitive method in the identification of cardiac right-to-left shunts also identified by TEE. The cardiac microemboli in this study did not show any side preference for one of the middle cerebral arteries.     

多层螺旋CT血管成像评价肝移植受者移植前后血管结构

背景：多层螺旋CT具有先进的扫描技术和强大的图像后处理功能,其亚秒级的扫描速度及各向同性的成像功能,在血管成像上有很多优势。 目的：探讨多层螺旋CT血管成像技术对肝移植受者移植前后血管结构评价的应用价值。 设计、时间及地点：回顾性分析,以肝移植受者肝脏血管为观察对象,自身对照观察,于2003-10/2006-12在中山大学附属第五医院放射科完成。 对象：选择拟行原位肝移植患者27例,年龄31~67岁,男17例,女10例。 方法：轴位螺旋扫描范围为膈顶上方2 cm至双肾下极以下。电压120 kV,动脉期准直0.75 mm,平扫、门脉期、肝静脉期准直1.5 cm;使用非离子型对比剂优维显,注射速度为3 mL/s,三期增强扫描延迟时间分别为20~25 s,50~55 s,75~80 s。重建增强的薄层图像序列,动脉期层厚1 mm,间隔0.7 mm;门脉期、肝静脉期层厚2 mm,间隔1 mm。将图像序列传入后处理工作站,以MIP、VR等方式显示腹腔干系、门脉系、肝静脉及下腔静脉血管的三维结构。 主要观察指标：肝移植前后患者血管三维结构。 结果：移植前所有患者腹腔干系均得到良好显示,21例肝动脉走形正常,6例患者肝动脉变异,其中门静脉海绵样变2例,门脉多发血栓1例,因不适宜手术此3例未进行肝移植。24例患者第二肝门及下腔静脉肝内段血管结构显示清楚,肝右静脉单独汇入下腔静脉、肝左静脉和肝中静脉先汇合后再注入下腔静脉18例,肝右静脉、肝中静脉及肝左静脉分别单独汇入下腔静脉6例,下腔静脉肝后段狭窄2例。17例肝移植后CT血管成像发现肝动脉吻合口部狭窄2例,门脉高压侧支迂曲缓解10例,另7例患者因检查费用问题选择B超检查。 结论：多层螺旋CT血管成像能够清晰显示肝移植患者移植前后血管结构,对适宜手术的病例筛选、指导手术方案及移植后血管结构的评价具有重要意义。     

A rare brainstem hemorrhage during transvenous embolization of a cavernous dural arteriovenous fistula

Intravascular treatment of cavernous dural arteriovenous fistula (dAVF) is usually safe and effective. However, we describe a patient with a rare brainstem hemorrhage during transvenous embolization (TVE). A 79-year-old woman suffered from left chemosis and diplopia. Cerebral angiography revealed a left cavernous dAVF with cortical venous drainage. The patient underwent TVE of the cavernous sinus (CS) via the left inferior petrosal sinus. Superior petrosal sinus (SPS) outflow occlusion was performed to avoid venous congestion, followed by superficial middle cerebral vein outflow occlusion, selective shunt occlusion of the middle meningeal artery, and superior orbital vein outflow occlusion. The patient's condition suddenly deteriorated during CS packing. A CT scan revealed a massive brainstem hemorrhage. Cerebral angiography did not show SPS reopening or redistributed drainage to the posterior fossa. Thus, TVE for cavernous dAVF can result in life-threatening vascular complications. Well-planned treatment strategies could avert this rare complication.     

Acute Ischemic Stroke Involving Both Anterior and Posterior Circulation Treated by Endovascular Revascularization for Acute Basilar Artery Occlusion via Persistent Primitive Trigeminal Artery

We report a case of acute ischemic stroke involving both the anterior and posterior circulation associated with a persistent primitive trigeminal artery (PPTA), treated by endovascular revascularization for acute basilar artery (BA) occlusion via the PPTA. An otherwise healthy 67-year-old man experienced sudden loss of consciousness and quadriplegia. Magnetic resonance imaging showed an extensive acute infarction in the right cerebral hemisphere, and magnetic resonance angiography showed occlusion of the right middle cerebral artery (MCA) and BA. Because the volume of infarction in the territory of the right MCA was extensive, we judged the use of intravenous tissue plasminogen activator to be contraindicated. Cerebral angiography revealed hypoplasia of both vertebral arteries and the presence of a PPTA from the right internal carotid artery. A microcatheter was introduced into the BA via the PPTA and revascularization was successfully performed using a Merci Retriever with adjuvant low-dose intraarterial urokinase. After treatment, his consciousness level and right motor weakness improved. Although persistent carotid-vertebrobasilar anastomoses such as a PPTA are relatively rare vascular anomalies, if the persistent primitive artery is present, it can be an access route for mechanical thrombectomy for acute ischemic stroke.     

Multiple cerebral embolism caused by a patent foramen ovale and a uterine myoma]

Recently, patent foramen ovale(PFO) has been highlighted as an important risk factor of cerebral infarctions in young adults. We report a patient of multiple cerebral embolism associated with PFO and deep venous thrombosis caused by a uterine myoma. A 40-year-old woman suddenly suffered from right hemiparesis with motor aphasia. Brain angiography showed an occlusion of M2 portion of the left middle cerebral artery, but atherosclerotic changes were not seen. She developed left facial paresis 23 days later and admitted to our hospital. Brain MRI revealed multiple cerebral infarcts in the left insular cortex, the deep white matter of the right frontal lobe, and bilateral thalamus. Hypoxia with the perfusion defects of S1 and S2 sections of the right lung demonstrated by scintigraphy suggested pulmonary embolism. Transesophageal echocardiography showed a PFO with spontaneous left-to-right shunt and right-to-left shunt evoked by the Valsalva maneuver. Although venography could not detect thrombi, it revealed severe compression of the right external iliac vein by a uterine myoma. These findings suggested thrombi in the right external iliac vein were the embolic source when combined with elevated coagulation markers. An uterine myoma should be considered as an important risk factor for an embolic source in case of cerebral embolism with PFO.     

经颅多普勒超声在不明原因缺血性脑卒中的应用研究

目的探讨经颅多普勒超声(transcranial Doppler,TCD)技术结合生理盐水发泡试验在不明原因缺血性脑卒中患者卵圆孔未闭(PFO)筛查中的应用价值。方法收集51例55岁以下不明原因缺血性脑卒中患者,行TCD结合生理盐水发泡试验和经胸超声心动图(TTE)检查。结果 51例患者中,23例患者TCD检查栓子信号阳性,其中18例患者TTE检查发现PFO,而在28例TCD检查栓子信号阴性的患者中未发现PFO;TCD检查阳性患者中偏头痛发病率、合并下肢深静脉血栓比例以及房间隔瘤比例较阴性者高(P<0.05)。结论 TCD结合生理盐水发泡试验是筛查PFO的有效手段,可以作为不明原因缺血性脑卒中病因筛查的手段。     

Limb-shaking transient ischemic attacks in an adult PHACE syndrome: a case report and review of the literature

PHACE syndrome is a neuro-cutaneous syndrome characterized by malformations of the Posterior fossa, facial Hemangiomas, Arterial anomalies, Cardiac anomalies, and abnormalities of the Eye. The arterial abnormalities usually involve the cervical and cerebral vasculature and include congenital abnormalities and progressive cerebral vasculopathy. The progressive cerebral vasculopathy leads to increased risk for arterial ischemic stroke (AIS) in patients with PHACE syndrome. Here we described the clinical neurological sequelae, the malformation of brain, the cervical and cerebral vasculopathy in a 23-year-old female of PHACE syndrome. Besides, she presented AIS with limb-shaking transient ischemic attack, a rare clinical presentation of AIS in patients of PHACE syndrome.     

Traumatic cerebral aneurysm formation following ventriculoperitoneal shunt insertion

Introduction Iatrogenic intracranial aneurysms are rare in children.Case report A 15-year-old girl presented in coma with a fixed dilated left pupil six weeks following removal of a long-standing left-sided ventriculoperitoneal shunt. Computed tomography (CT) and cerebral angiography revealed a left temporoparietal intracerebral haemorrhage with a fusiform distal middle cerebral artery aneurysm. The patient underwent image-guided localisation of the aneurysm to enable evacuation of the haemorrhage and resection of the fusiform aneurysm.Conclusion A high index of suspicion is required for diagnosis and early treatment to prevent unnecessary morbidity and mortality.     

Validation of hyperintense middle cerebral artery sign in acute ischemic stroke Comparison between magnetic resonance imaging and angiography

We performed a retrospective analysis of non-contrast computed tomography (CT) scans, immediately subsequent magnetic resonance imaging (MRI), and cerebral angiography data from 30 consecutive patients with acute ischemic stroke within 6 hours after symptom onset. Results showed that eleven patients developed subsequent hemorrhagic transformation at follow-up. A hyperintense middle cerebral artery sign on MRI was found in six hemorrhagic patients, all of who had acute thrombosis formation on magnetic resonance angiography and digital subtraction angiography. No patients in the non-hemorrhagic group had hyperintense middle cerebral artery sign on MRI. The sensitivity, specificity, and positive predictive values of the hyperintense middle cerebral artery sign on MRI T1-weighted image for subsequent hemorrhagic transformation were 54.5%, 100%, and 100% respectively. Hyperdense middle cerebral artery sign on non-contrast CT was observed in nine patients, five of who developed hemorrhagic transformation. These data suggest that hyperintense middle cerebral artery sign on MRI T1-weighted image is a highly specific and moderately sensitive indicator of subsequent hemorrhagic transformation in patients after acute ischemic stroke, and its specificity is superior to CT.     

Middle cerebral artery dolichoectasia in a young woman with a previous stroke

We observed a 32-year-old female who had suffered from a left hemisphere ischemic stroke with right hemiparesis at the age of seven. At that time, a CT scan demonstrated a left ischemic lesion in nucleo-capsular region and a cerebral angiogram documented a complete occlusion of the supraclinoid segment of the internal carotid artery. When we observed the patient neurological examination demonstrated a moderate right brachio-crural hemiparesis. A brain MRI showed an old ischemic lesion involving the left nucleo-capsular and 'flow voids' suggestive for a vascular malformation in the left sylvian region. A cerebral rotational angiogram with 3-D reconstructions demonstrated a dolichoectatic left middle cerebral artery with an unusual 'corkscrew' aspect. Middle cerebral artery dolichoectasia is a rare pathological condition that may manifest with a stroke. The patients with intracranial arterial dolichoectasia (IADE) are most often hypertensive elderly men, and, to the best of our knowledge, an ischemic stroke associated with IADE has never been reported in children.     

Prominent persisting Eustachian valve initiates spontaneous right-to-left shunt and paradoxical embolism in a patient with patent foramen ovale

The Eustachian valve (EV) is an embryological remnant of the inferior vena cava valve that prenatally directs the oxygenated blood from inferior vena cava across the patent foramen ovale (PFO) into systemic circulation. We present a 30-year-old man with PFO whose prominent EV initiated spontaneous right-to-left shunt without Valsalva maneuver and promoted paradoxical embolism. Even when the persistence of EV is prominent in adult, it has been considered to be benign finding in the absence of the associated cardiac anomalies. EV should be considered as an adjunctive risk factor for paradoxical embolism in patients with PFO.     

Fusiform aneurysm of a persistent trigeminal artery.

OBJECTIVE: Fusiform aneurysms of the persistent trigeminal artery are rare and endovascular treatment of these aneurysms has not been attempted previously. We describe a case of persistent trigeminal artery with a fusiform aneurysm in its middle third, managed using Guglielmi detachable coils (GDC). CLINICAL PRESENTATION: A 50-year-old, diabetic and hypertensive patient presented with sudden onset headache and neck stiffness. On examination, she was conscious but disoriented, without cranial nerve or sensorimotor deficits. Four-vessel cerebral digital subtraction angiography revealed a fusiform aneurysm of the middle third of a persistent trigeminal artery on the left side with adult type posterior cerebral arteries. INTERVENTION: Guglielmi detachable coils were used for occlusion of the persistent trigeminal artery. RESULTS: The procedure was well tolerated but delayed ischemic neurological deficits developed due to vasospasm. CONCLUSIONS: (1) In spite of angiographically documented independence of the anterior and posterior cerebral circulation, occlusion of a persistent trigeminal artery using endovascular techniques may result in posterior circulation stroke due to a number of factors, including occlusion of brainstem perforators taking origin from the persistent trigeminal artery or vasospasm. (2) The timing for endovascular intervention following aneurysmal rupture remains poorly defined.     

Brain abscess following intra-arterial thrombolytic treatment for acute brain ischemia

Brain abscess formation is a rare complication of intracranial endovascular treatment. To our knowledge, all previous reports of brain abscess formation have been associated with treatments involving the introduction of foreign materials. A 75-year-old man was admitted to hospital for acute stroke. Cerebral angiography revealed occlusion of the left middle cerebral artery (MCA) at the origin of the M2 segment. Intra-arterial thrombolytic therapy was administered but a hemorrhagic event occurred during this process. A brain CT scan revealed a hematoma extending from the left basal ganglia to the left frontal lobe and expansion of the infarct in the left MCA territory. A brain abscess at the hemorrhagic site developed 3 months after symptom onset. This is the first report of a patient with brain abscess formation following intra-arterial thrombolytic treatment. It is important to ensure aseptic technique during endovascular procedures irrespective of the involvement of foreign materials.     

Ischemic Stroke with Protein S Deficiency Treated by Apixaban

A 57-year-old man with atherosclerosis obliterans was admitted with sudden-onset sensory aphasia and right hemiparesis. Brain MRI revealed acute cerebral infarctions in the left temporal lobe and magnetic resonance angiography showed occlusion of the posterior branch of the left middle cerebral artery. Transesophageal echocardiography and ultrasonography respectively confirmed a patent foramen ovale and deep vein thrombosis in the bilateral femoral veins. Blood findings showed low protein S antigen, low protein S activity, and a missense mutation of the PROS 1 gene. The administration of apixaban 10 mg BID prevented ischemic stroke recurrence and decreased the deep vein thrombosis. These outcomes indicated that apixaban may be alternative to warfarin for the secondary prevention of ischemic stroke in a patient with a protein S deficiency.     

Basilar artery thrombosis during sexual intercourse

An ischemic stroke during sexual intercourse is very rare. A basilar artery thrombosis during sexual intercourse has not been described previously. We report a young woman with a life-threatening basilar artery thrombosis during sexual intercourse, with a resulting locked-in syndrome. The positive high intensity transient signals (HITS) diagnosis showed a right-to-left shunt and is in line with paradoxic embolism. The molecular genetics revealed a homozygosity 4G/4G in the region PAI1, -675 (promoter polymorphism) as a risk factor for ischemic stroke. Sexual intercourse is a possible, albeit unusual stroke cause, especially in young people.