Incidental aneurysm of the superior cerebellar and non-visualized posterior inferior cerebellar artery: a diagnostic trap

Summary The authors report a case of two aneurysms in the posterior fossa, one of which was first visualized on follow-up arteriography. The mechanism of non-vasualization and re-appearance of the aneurysm is discussed.     

Spontaneous dissection of the anterior inferior cerebellar artery

A patient presented with the clinical features of a brain stem infarct. MRI confirmed changes of infarction but also revealed an unusual lesion in the left cerebellopontine angle cistern. The evolution of this lesion on MRI, together with angiographic changes, indicated a dissecting aneurysm of the left anterior inferior cerebellar artery, a previously unreported phenomenon. The presentation, causes and diagnosis of intracranial dissection are discussed. Received: 2 September 1999 Accepted: 16 September 1999     

Coil embolisation for ruptured vertebral artery dissection distal to the origin of the posterior inferior cerebellar artery

Although many surgical or endovascular treatments for ruptured vertebral artery dissection have been reported, the best treatment is controversial. We treated five cases of ruptured vertebral artery dissection distal to the origin of the posterior inferior cerebellar artery (PICA), using retrievable platinum coils packed in the dissection site and the immediately proximal vertebral artery. All patients had a contralateral vertebral artery of the same calibre or larger. All dissections were occluded completely, together with the portion of the vertebral artery distal to the PICA origin. No complications related to the procedure were seen. The purpose of the treatment is to isolate the dissection from the cerebral circulation. Occlusion of the rupture site, preserving perforating arteries arising from the vertebral artery, would be ideal. Short-segment occlusion by retrievable platinum coils is close to the ideal. Received: 21 December 1998/Accepted: 21 July 1999     

Double origin of the posterior inferior cerebellar artery

Double origin of the posterior inferior cerebellar artery (PICA) has rarely been demonstrated by angiography in the peer-reviewed literature. Of the three previous reports, this PICA variant arose from the left vertebral artery. We report a right-sided, double-origin PICA.     

Ruptured, dissecting posterior inferior cerebellar artery aneurysms: endovascular treatment without parent vessel occlusion

Introduction Treatment of a dissecting aneurysm of the medullary segments of the posterior inferior cerebellar artery (PICA) usually entails trapping of the diseased arterial segment with possible sacrifice of brainstem perforators. The goal of the work was to review our experience with selective coiling of ruptured, dissecting aneurysms of the anterolateral segments of the PICA without parent vessel occlusion. Methods Eleven consecutive patients (9 women, 2 men, mean age 47.2 years) were retrospectively reviewed from a prospectively acquired neuroradiological database. On admission three patients had Hunt and Hess (HH) grade I, three HH grade II, two HH grade III, and one HH grade IV. Outcome was evaluated according to the modified Rankin scale (mRS) score. Follow-up (mean:19.4 months) consisted of magnetic resonance angiography and/or digital subtraction angiography in ten patients. Results Ten patients had mRS score 0 and one mRS score 2. No treatment failure occurred. The aneurysm was completely occluded in seven patients, a neck residue was present in two, and a loose coil mesh was present in two. Recurrence occurred in three patients, and all were successfully retreated for a total of 13 procedures. Procedure-related complications were all without clinical consequences and included a coil perforation in one procedure and stagnant filling of the parent vessel in six procedures. PICA occlusion did not occur in any patient. Conclusion Coiling of ruptured, isolated dissecting aneurysms of the PICA without parent vessel occlusion is feasible, relatively safe and effective in preventing early/medium-term rebleeding. A strict angiographic follow-up program is, however, necessary to detect recurrence.     

Intracranial vessel wall MR imaging of an intradural vertebral artery dissection

Diagnosis of intracranial arterial dissections can be challenging due to the wide spectrum of imaging presentations. High-resolution vessel wall MR imaging can be a useful adjunct to conventional lumen-based imaging techniques for diagnosing arterial dissections. We present a case of a 37-year-old male with a history of a Wolff-Parkinson-White syndrome presenting with acute onset of nausea, vertigo, and left body hemisensory loss of pain and temperature. A conventional brain MRI identified an acute infarct in the right lateral medulla, concordant with clinical symptoms of Wallenberg syndrome. CT angiogram of the head and neck showed lack of opacification of the right intradural vertebral artery. Intracranial vessel wall MR imaging showed findings suggestive of an intimal dissection flap with both intramural and intraluminal thrombus. Intracranial vessel wall MR imaging can provide complementary information to conventional lumen-based imaging to diagnose a vertebral dissection.     

Isolated dissecting aneurysm of the left posterior inferior cerebellar artery: endovascular treatment with a Guglielmi detachable coil.

An isolated progressive dissecting aneurysm of the left posterior inferior cerebellar artery (PICA) associated with a persistent trigeminal artery was successfully treated by endovascular occlusion of the proximal PICA with a Guglielmi detachable coil.     

Endovascular treatment of the posterior inferior cerebellar artery aneurysms

Aneurysms may arise at various locations along the course of the posterior inferior cerebellar artery. Brainstem and cranial nerves manipulation make the surgical approach to proximal aneurysms difficult, while the occlusion of the parent vessel is sometimes unavoidable in peripheral aneurysms. Endovascular treatment can be a good alternative, but also with this approach the location of the aneurysm is critical. If occlusion of the parent vessel is planned, anatomical variations and vascular territories of the brainstem should be considered. We report our experience with 18 consecutive aneurysms (12 proximal, 6 peripheral) treated by coils. Complete occlusion was achieved in 14 patients and subtotal in 4. In three patients the parent vessel had to be sacrificed. During treatment two perforations occurred; aneurysms were completely occluded without clinical consequences. Two small asymptomatic cerebellar infarctions were seen on postoperative computed tomography. Clinical outcome was good in 16 patients     

Isolated posterior cerebral artery dissection: report of three cases

Isolated dissection of the posterior cerebral artery (PCA) is a rare but important cause of stroke in younger patients, particularly women. We present 3 cases of dissection of the P2 segment of the PCA. In 2 patients, an association with minor axial head trauma was documented, suggesting shearing injury of the PCA as it crosses over the free edge of the tentorium. The clinical and imaging findings are discussed, and the therapeutic management is reviewed.     

Endovascular treatment of peripheral aneurysms of the posterior inferior cerebellar artery

BACKGROUND AND PURPOSE: Peripheral aneurysms of the posterior inferior cerebellar artery (PICA) are rare, and pre-existing literature concerning their endovascular treatment is limited. The purpose of this study was to assess the etiology and clinical characteristics of peripheral PICA aneurysms and to evaluate the angiographic and clinical results of the patients who underwent endovascular treatment for a peripheral PICA aneurysm in a single center.MATERIALS AND METHODS: Twelve consecutive patients with 12 peripheral PICA aneurysms (10 ruptured) included in an internal data base were retrospectively reviewed. Posttreatment and follow-up angiograms were analyzed, and the clinical outcome was recorded.RESULTS: The etiology was dissection in 7 (58%) and unknown in 5 cases (42%). Three dissecting aneurysms reruptured before endovascular treatment, and another 3 demonstrated angiographic progress. Four aneurysms were treated by endosaccular coiling, 6 (all dissecting) by parent artery occlusion, and in 2 cases endovascular treatment failed. Angiographic outcome was complete aneurysm and/or parent artery occlusion in 9 cases and neck remnant in 1 case. One aneurysm needed retreatment at follow-up. One lethal procedural complication occurred, and transient ischemic symptoms appeared in 2 patients. The clinical outcome was good in 7 patients, whereas 3 patients, all poor clinical grade, died (1 for unrelated reasons). No rebleedings have occurred during the follow-up.CONCLUSION: In this series, most peripheral PICA aneurysms were secondary to arterial dissection. They were unstable with a high risk of rebleeding and a high mortality if not treated without delay. Endovascular treatment was effective in preventing rehemorrhage.

Posterior inferior cerebellar artery (PICA) aneurysms account for approximately 0.5% to 3.0% of all intracranial aneurysms,^1,2 and most are located right at the origin or in the first anteromedullary segment of the vessel.^2-4 Roughly, only a fifth of the PICA aneurysms are thought to arise from more distal segments of the PICA.^2-4 Approximately 28% of all aneurysms located in the vertebrobasilar arteries, including PICA, have been estimated to be of dissecting origin.⁵ Among peripheral PICA aneurysms, dissecting etiology has been found in 0%-80% of the cases.^6-9Due to anatomic location of the PICAs (proximity to brain stem and lower cranial nerves), their surgical treatment is associated with significant risk of neurologic complications.¹⁰ Endovascular technique enables treating these lesions without craniotomy and the risks related to surgical manipulation. Despite the recently increased number of publications, the pre-existing literature concerning endovascular treatment of peripheral PICA aneurysms is limited and controversial.^6-9,11-21 In the present study, a consecutive series of 12 patients harboring a peripheral PICA aneurysm allocated for endovascular treatment in a single center was retrospectively analyzed.     

Anomalous origin of the posterior meningeal artery from the lateral medullary segment of the posterior inferior cerebellar artery

Summary The authors present two cases of angiographically-confirmed anomalous origin of the posterior meningeal artery (PMA) from the lateral segment of the posterior inferior cerebellar artery (PICA) and describe briefly the probable embryogenesis of this anomaly.     

Anomalous origin of the posterior inferior cerebellar artery from the internal carotid artery.

A rare anomalous origin of the posterior inferior cerebellar artery arising from the internal carotid artery is described. The embryologic explanation postulated is the persistence of a primitive communicating vessel (presegmental artery) between the anterior and posterior circulation.     

The posterior inferior cerebellar artery originating from the internal carotid artery,associated with multiple aneurysms

Summary We report the rare case of ipsilateral posterior inferior cerebellar artery originating from the carotid artery, and associated with multiple concurrent aneurysms. This is the 23rd reported case of carotid-cerebellar anastomosis and the first case with three concurrent aneurysms reported in the literature. Of the 23 cases, 6 had single aneurysms, 2 had double aneurysms and the present case had triple aneurysms.     

Endovascular treatment of isolated dissecting aneurysm of the posterior inferior cerebellar artery

BACKGROUND AND PURPOSE: Isolated dissecting aneurysms of the posterior inferior cerebellar artery (PICA) carry a high risk of rebleeding with an associated increased mortality rate. Although rare, they present a therapeutic challenge. Surgical treatment carries a significant risk of neurologic complications, predominantly lower cranial nerve deficits because of the close relationship of the aneurysm with the brain stem and cranial nerves. The purpose of this article is to show that endovascular treatment of dissecting aneurysms of the PICA can be effective and can allow the patient to avoid the complications associated with surgery. METHODS: Six patients (age range, 28-70 years) with dissecting aneurysms of the PICA were treated at our center by endovascular occlusion with Guglielmi detachable coils or glue and followed for up to 30 months. Inclusion of patients in the study was based on careful angiographic assessment of the vascular anatomy and collateral supply of the posterior fossa. When on the basis of the anatomy, potential lack of sufficient collaterals was suggested, a test occlusion was performed to determine the feasibility of an endovascular approach. Four additional cases, which have been described in the literature, were included in the analysis of results. RESULTS: In all patients, the aneurysm was successfully occluded with no apparent procedure-related complications. Follow-up studies showed stable and complete occlusion of the aneurysm in all patients with no long-term neurologic deficits. CONCLUSIONS: Endovascular treatment by aneurysm and parent artery occlusion is a relatively safe and reliable alternative to surgery for isolated dissecting aneurysms of the PICA.     

高分辨力MR血管壁成像在急性缺血性脑卒中临床决策中的应用进展

高分辨力MR血管壁成像（HR-VWI）是目前评价颅内血管管壁的无创影像学检查方法,能够准确识别管腔及管壁特征,具有较高的可重复性。其在急性缺血性脑卒中（AIS）病因分型、症状性颅内动脉责任斑块评估、预测卒中复发、评估药物及血管内治疗效果等方面发挥着作用,有利于AIS临床决策的制定。就HR-VWI在AIS临床决策中的应用进展进行综述。     

高分辨力MR血管壁成像技术在头颈动脉夹层诊断中的应用价值

目的探讨高分辨力MRI(HRMRI)在头颈动脉夹层诊断中的价值。方法前瞻性连续纳入2015年2月—2017年6月于宣武医院就诊的头颈动脉夹层病人30例,采用32通道头颈联合专用线圈行头颈一体化HRMRI成像。由2名神经内科医生根据纳入病人的临床病史、实验室检查、常规影像检查对夹层做出诊断并作为参考标准。由2名放射科医生对CTA和HRMRI影像进行双盲分析,评价内容包括内膜片、壁内血肿及双腔征等。计算CTA和HRMRI在血管节段水平诊断夹层的准确性。结果 (1)2名神经内科医生在30例病人中共诊断41个血管节段存在夹层,其中累及颈内动脉18个节段、椎动脉18个节段、基底动脉5个节段。(2)CTA正确诊断21个血管节段存在夹层(21/41,敏感度51.2%),其中6个血管节段见双腔征。(3)HRMRI正确诊断39个血管节段存在夹层(39/41,敏感度95.1%),其中36个血管节段见壁内血肿,30个血管节段见双腔征。结论头颈联合HRMRI可全景显示夹层动脉管壁特征,可作为动脉夹层诊断和随访的一线检查技术。