Bilateral spontaneous dissection of the posteroinferior cerebellar arteries: case report

Overlapping Pure LIVS Jr. Stents for Isolated Ruptured Dissecting Aneurysm of the Proximal Posterior Inferior Cerebellar Artery

We report our experience in treating a ruptured dissecting posterior inferior cerebellar artery (PICA) aneurysm. To our knowledge, this is the first reported case of overlapping stenting without coils for a ruptured dissecting aneurysm of the proximal PICA. A 66-year-old male patient presented with sudden altered mental state and a subarachnoid hemorrhage (SAH). The cerebral angiography revealed a long segmental dissecting aneurysm on proximal PICA. Overlapping stents were deployed to the dissecting site, and angiogram showed intact distal PICA flow and decreased contrast staining in the dissecting site. Successful flow diversion was achieved with stents. Procedure-associated complications did not occur. The patient’s postoperative course was uneventful. In follow-up cerebral angiography, dissecting aneurysm achieved complete remodeling. The decision that led to the choice of treatment is discussed.

Sequential Bilateral Vertebral Artery Dissections with Prompt Resolution of Initial Insult

Vertebral arterial dissection is a known cause of stroke in young adults. There has been a multitude of cases of bilateral vertebral dissections, including progression from one vertebral artery to another. This case reports the curious sequential nature of the healing of a previously dissected vertebral artery with subsequent dissection of the collateral vertebral artery. Follow-up neuroimaging evaluation performed several months later showed healed bilateral vertebral artery. The potential trigger was neck cracking.

Republished: Delayed subarachnoid hemorrhage 7 years after cerebellar infarction from traumatic vertebral artery dissection

Vertebral artery dissection (VAD) is an important cause of ischemic stroke and subarachnoid hemorrhage (SAH). Dissections presenting with ischemia rarely cause SAH after more than a few hours, especially without radiographic evidence of pseudoaneurysm. We successfully treated a patient for persistent vessel injury presenting with SAH 7 years after presenting with extracranial subocclusive dissection of the right vertebral artery and an associated right posterior inferior cerebellar artery stroke. This is one of only three reported cases of delayed SAH occurring more than 2 weeks after an initial ischemic presentation of a VAD, and the only one without radiographic evidence of pseudoaneurysm at standard follow-up duration.

Delayed subarachnoid hemorrhage 7 years after cerebellar infarction from traumatic vertebral artery dissection

Vertebral artery dissection (VAD) is an important cause of ischemic stroke and subarachnoid hemorrhage (SAH). Dissections presenting with ischemia rarely cause SAH after more than a few hours, especially without radiographic evidence of pseudoaneurysm. We successfully treated a patient for persistent vessel injury presenting with SAH 7 years after presenting with extracranial subocclusive dissection of the right vertebral artery and an associated right posterior inferior cerebellar artery stroke. This is one of only three reported cases of delayed SAH occurring more than 2 weeks after an initial ischemic presentation of a VAD, and the only one without radiographic evidence of pseudoaneurysm at standard follow-up duration.

Remote distal outflow occlusion: a novel treatment option for complex dissecting aneurysms of the posterior inferior cerebellar artery. Report of 3 cases

The authors report a novel management option for patients with complex dissecting aneurysms of the posterior inferior cerebellar artery (PICA). The authors reviewed the medical records and neuroimaging studies of 3 patients who underwent a novel surgical treatment for complicated dissecting PICA aneurysms. The mean follow-up period was 1.1 years, and no patient was lost to follow-up. Two patients were in poor condition following an acute, severe subarachnoid hemorrhage, and 1 presented with headaches and a remote history of bleeding. All patients underwent surgical occlusion of the PICA beyond the tonsillar loop, distal to the aneurysmal segment. Intraoperative and delayed follow-up angiography demonstrated progressive diminution in size of the aneurysmal dilation but persistent filling of the proximal PICA segments supplying the brainstem. Outcome was good in all cases. This novel technique has been used successfully in 3 cases and, to the authors' knowledge, has not been reported previously.

Dissecting aneurysms of the posterior inferior cerebellar artery: retrospective evaluation of management and extended follow-up review in 6 patients

OBJECT

The authors report the management protocol and successful outcomes in 6 patients with dissecting aneurysms of the posterior inferior cerebellar artery (PICA).

METHODS

Medical records and neuroimaging studies of 6 patients who underwent surgical treatment of dissecting PICA aneurysms were reviewed. The mean follow-up duration was 1.8 years. No patient was lost to follow-up review.

RESULTS

Four patients presented with acute subarachnoid hemorrhage and 2 with PICA ischemia. All patients underwent surgery, which entailed proximal occlusion with distal revascularization in 3 cases and circumferential wrap/clip reconstruction in 3 cases. The revascularization techniques used were occipital artery-PICA bypass and PICA-PICA anastomosis. Delayed follow-up angiography was performed in all cases. In patients treated with proximal occlusion, delayed angiography showed minimal retrograde opacification of the dissected segments. The 3 patients treated with wrap/clip reconstruction showed unexpectedly significant normalization of their lesions on angiographic studies. Outcome was good in all cases.

CONCLUSIONS

Dissecting PICA aneurysms are rare lesions with an apparent propensity for bleeding. Individualized management including distal revascularization with PICA sacrifice or circumferential wrap/clip reconstruction to reinforce the dissected segment produced good outcomes. Patients treated with aneurysm wrapping may show dramatic angiographic improvement of the dissected segment.

Dissection of the superior cerebellar artery: a report of two cases and review of the literature

Arterial dissections frequently involve the main trunk of the posterior circulation and are recognised as an important cause of stroke in young individuals. However, dissection confined to cerebellar arteries is rare. We encountered two patients with superior cerebellar artery (SCA) dissection. A 37-year-old man presented with dysarthria, right limb ataxia, and severe headache. Magnetic resonance imaging revealed cerebellar infarction in the right SCA territory. Angiography demonstrated stenosis and fusiform dilation of the SCA in the anterior pontine segment. Recovery with antiplatelet treatment was nearly complete. A 45-year-old man was admitted with decreased consciousness after sudden onset of headache. Computed tomography demonstrated subarachnoid haemorrhage with hydrocephalus. Angiography revealed fusiform dilation of the left SCA in the anterior pontine segment. After ventricular drainage, endovascular embolisation was performed without ischaemic complications. The patient's condition improved sufficiently to return to daily life. In our search only four reported cases involved the SCA. Clinical manifestation and treatment for patients with cerebellar arterial dissections are discussed.

Spontaneous resolution of isolated dissecting aneurysm on the posterior inferior cerebellar artery

The authors report a rare example of an isolated dissecting posterior inferior cerebellar artery (PICA) aneurysm with spontaneous resolution. A 41 year-old male suffered sudden dizziness, nausea and vomiting. An angiogram and magnetic resonance imaging (MRI) detected an isolated PICA dissection. The patient was treated conservatively and recovered without any apparent neurological deficit. MRI detected the self-resolution of the dissecting aneurysm. Dissecting PICA aneurysms, especially non-haemorrhagic lesions, have the possibility of spontaneous resolution resulting in a favorable outcome. The treatment strategy for this vascular lesion may be decided based upon neuroradiological changes on careful follow-up.

Dissection of the posteroinferior cerebellar artery: clinical characteristics and long-term follow-up in five cases

BACKGROUND AND PURPOSE

Spontaneous isolated posteroinferior cerebellar artery (PICA) dissection is very rare. The aim of the study was to investigate the clinical manifestations, the neuroradiological aspects and the treatment of 5 cases collected in 5 years.

METHODS AND RESULTS

From 1999 to 2003, five patients (40-71 years old) were hospitalized for PICA dissection. Two patients presented symptoms after cervical manipulation. No predisposing factor or traumatic cause was described in the other cases. The diagnosis was carried out by cerebral angiography in all the cases: in 4, angiography showed focal stenosis with saccular or fusiform dilatation of the artery at the site of the dissection; in 1 a double lumen aspect was described. One patient presented ischemic manifestations; he was treated with heparin. The others presented subarachnoid hemorrhage (SAH) and were treated by embolization (endovascular sacrifice of the PICA). No ischemic complication and no rebleeding were observed after sacrifice of the PICA. Three patients presented acute hydrocephalus and were treated with surgical derivation. The angiographic and clinical follow-up lasted more than 3 years. We assessed the long-term results with the Glasgow Outcome Score and the modified Rankin Score. A good recovery was achieved for 4 patients (modified Rankin Score 0); one patient who presented SAH and who was in bad clinical state on admission had a Glasgow Outcome Score of 3 and a modified Rankin Score of 4 three years later.

CONCLUSION

Clinical course and prognosis are variable in PICA dissections. The treatment depends on the existence of a hemorrhagic event. In the group of patients presenting SAH, endovascular treatment was safe and effective. The long-term clinical results depend mainly on the clinical status on admission.

Two cases of dissecting aneurysm of the distal posterior inferior cerebellar artery: possible involvement of segmental mediolytic arteriopathy in the pathogenesis

BACKGROUND

Dissecting aneurysm of the posterior inferior cerebellar artery (PICA) uninvolved with the vertebral artery is rare. The exact pathohistological diagnosis might result in 'unknown' because the underlying pathoanatomical features are, for a variety of reasons, not always identified.

CASE DESCRIPTION

We report herein two cases of dissecting aneurysm harbored in different segments of the distal posterior inferior cerebellar artery. In our cases, after trapping the PICA at both just proximal and distal to the aneurysm, the abnormal portion was successfully resected with/without an end-to-end anastomosis. The first patient made a good recovery, while the other died 2 days after the surgery. Although its pathogenetic etiology was unidentified in the second case, the formation of dissecting aneurysm had resulted from a segmental mediolytic arteriopathy in the first case.

CONCLUSION

This is the first report of a segmental mediolytic arteriopathy possibly being identified as causing an isolated dissecting aneurysm at this site.

Treatment of hemorrhagic intracranial dissections

OBJECTIVE

To analyze the treatment options in hemorrhagic intracranial dissections.

METHODS

This study involved a retrospective review of 27 patients with 29 dissections treated during a 16-year period, mainly by endovascular treatment (EVT).

RESULTS

EVT was performed in the acute stage in 12 of the 29 dissections, and occlusion was performed using coils at the dissection site in six dissections and with proximal balloon occlusion in six dissections. Wrapping was performed in one case. In the remaining 16 dissections, which were not treated, mainly for anatomic reasons, three patients died, one from rebleeding. Angiographic follow-up performed in the 13 surviving patients demonstrated an initially misdiagnosed lesion in one and worsening lesions in five that led to delayed EVT in five and surgical clipping in one. One of these dissections, which was located on a dominant vertebral artery, was treated after subsequent rupture using a stent and coils to preserve the patency of the parent vessel. Four ischemic complications related to EVT resulted in a moderate disability in two patients. No rebleeding occurred after EVT, but one patient died because of a poor initial clinical status; the other patients improved. In the 10 patients treated conservatively, four died, three from a poor initial clinical status and one from rebleeding, and six patients had a good clinical outcome. Of the 27 patients, three had rebleeding and one died as a result of that rebleeding. Seventeen patients (63%) had a good recovery, six (22%) had a moderate disability, and four (15%) died.

CONCLUSION

EVT provides effective protection against rebleeding. When possible, occlusion with coils at the dissection site is the current method of choice. Another option is parent artery occlusion with balloons, and the use of a stent may preserve vessel permeability in specific cases.

Isolated dissections and dissecting aneurysms of the posterior inferior cerebellar artery: topic and literature review

Isolated dissections of the posterior inferior cerebellar artery (PICA) are rare. Thus, no large series of cases have been reported in the literature. Due to limited knowledge regarding the natural history of these lesions and the lack of high-quality evidence supporting various treatment options, management is controversial and practice parameters are ill defined. In order to offer a comprehensive reference for the diagnosis and management of isolated PICA dissections, the authors reviewed the National Library of Medicine from 1966 to October 2001. Twenty-seven patients averaging 43.6 years of age and including 14 males and 13 females were reported. Subarachnoid hemorrhage occurred in 20 patients, and two died. Dissections were located in the proximal PICA in 22 patients and were three times more common on the left side (left:right=3:1). Six patients were managed conservatively, and four with endovascular techniques. Seventeen had open surgery: five underwent resection, two went through trapping, and two had proximal clipping. Wrapping with muscle was performed in two patients, encasement with Sundt clips in two, and four had occipital artery (OA)-PICA bypass surgery. A meticulous analysis of reported cases with regard to clinical and pathological features, management strategies, and outcomes is presented.

Distal posterior inferior cerebellar artery aneurysms: clinical features and management

OBJECT

Aneurysms located on the distal portion of the posterior inferior cerebellar artery (PICA) are uncommon, and their underlying pathology, natural history, and clinical management are poorly understood. To clarify these lesions more fully, the authors undertook a retrospective analysis of the clinical features and management results of 22 distal PICA aneurysms in 20 consecutive patients treated at one institution by the same surgeon during the past decade.

METHODS

The series included 10 men and 10 women (mean age at presentation 51 years). Nine patients presented with only subarachnoid and/or intraventricular hemorrhage (median Hunt and Hess Grade II). In seven patients intracerebellar hemorrhage was also found; two patients presented with pressure effects and two hemorrhages were incidentally discovered. Prominent comorbidities included cigarette smoking (50%) and hypertension (50%). The 13 saccular and nine fusiform distal PICA aneurysms were distributed on the following segments of the PICA: lateral medullary (seven lesions), tonsillomedullary (five lesions), telovelotonsillar (five lesions), and cortical (five lesions). Six oases were associated with cerebellar arteriovenous malformations. Skull-base and far-lateral transcondylar surgical approaches were used to secure the aneurysms in 86% of cases, either by direct clipping (13 lesions), vessel sacrifice (four lesions), or vessel sacrifice plus bypass (two lesions). Two aneurysms were treated using endovascular PICA ablation. Overall outcome at hospital discharge was excellent or good in 70% of cases. At long-term follow up (100% of patients, mean 123 days), an excellent or good outcome had been achieved in 85% of cases.

CONCLUSIONS

Depending on the PICA segment that was affected, variations in clipping strategies and surgical exposures aimed at the PICA branch and main trunk preservation were major contributors to good long-term results.

Trapping and revascularization for a dissecting aneurysm of the proximal posteroinferior cerebellar artery: technical case report and review of the literature

OBJECTIVE AND IMPORTANCE

Subarachnoid hemorrhage caused by an isolated dissection of the proximal portion of the posteroinferior cerebellar artery (PICA) is a rare problem. The optimal treatment to use for patients presenting with this clinical scenario varies and therefore is controversial in the literature. We report a patient in whom this problem was treated effectively with trapping of the diseased segment and revascularization of the PICA. We report this case to review this rare topic and to present our perspective on the indications for and the effectiveness of trapping and revascularization for proximal PICA dissections that cause hemorrhage.

CLINICAL PRESENTATION

A 55-year-old man was transferred to our institution and admitted for Hunt and Hess Grade IV subarachnoid hemorrhage, which improved to Hunt and Hess Grade III after ventricular drainage. Imaging revealed the source of the hemorrhage to be a pseudoaneurysm related to the dissection of the proximal portion of the PICA.

INTERVENTION

Three days after the initial bleeding episode, we operated on the patient. After the occipital artery was prepared for bypass, the diseased segment was trapped. The occipital artery-to-PICA anastomosis was then immediately performed distal to the trapped segment.

CONCLUSION

On the basis of our experience, the literature regarding this topic, and the anatomy of the perforators of the PICA, we think that the best treatment for a pseudoaneurysm located within the first three segments of the PICA is trapping of the diseased segment followed by revascularization distal to the trapped segment. This approach should prevent rehemorrhage and should avoid iatrogenic ischemic complications of the brainstem.

A dissecting aneurysm of the posterior inferior cerebellar artery. A case report

SUMMARY

Dissecting aneurysms occur when blood extrudes into the wall of a vessel. Posterior circulation dissections are recognised as an important cause of cerbral infarction and subarachnoid haemorrhage(SAH), however posterior inferior cerebellar artery (PICA) aneurysmal dissections are rare. A 49-year-old man who presented with SAH was found to have a left PICA dissection on cerebral angiography. The lesion was treated with surgical clipping proximal to the dissection and a distal PICA to PICA anastomosis. The pathology, diagnosis, presentation and treatment of these difficult lesions is discussed.

Dissecting aneurysms of the posterior inferior cerebellar artery: report of four cases and review of the literature

Dissecting aneurysms frequently involve the vertebral arteries and their branches, but those exclusively on the posterior inferior cerebellar artery (PICA) represent only 24 cases in the literature, including the four cases discussed in this article. The clinical diagnosis lacks pathognomonic signs or symptoms, with presentations such as subarachnoid haemorrhage or ischaemia of the brain stem or the cerebellum, and the management is controversial. Wrapping, clipping and embolisation of the aneurysms were tried in this series with different outcomes. Exclusion of the pathological segment should be performed, as shown by rebleeding from our case which was wrapped or by progression of the vascular disease in cases where treatment was delayed. Surgical or endovascular occlusion are well tolerated in our cases and in those reported from the literature, which implies the absence of normal perforating branches to the brain stem arising from the proximal dissected segment of the PICA and a good collateral circulation. A revascularisation procedure using the occipital artery can be performed in order to prevent infarction if an endovascular test occlusion is not tolerated.

Acute traumatic posteroinferior cerebellar artery aneurysms: report of three cases

OBJECTIVE AND IMPORTANCE

Posterior fossa subarachnoid hemorrhage secondary to blunt head trauma is rarely associated with traumatic aneurysms of the posterior circulation.

CLINICAL PRESENTATION

We present three cases of posterior fossa subarachnoid hemorrhage from ruptured posteroinferior cerebellar artery (PICA) aneurysms after blunt head trauma. In each case, there was no associated penetrating injury or cranial fracture. All three patients presented with acute hydrocephalus requiring ventriculostomy. Two of the three patients had a proximal PICA aneurysm visible on emergent angiography. The remaining patient's aneurysm, although not visible on his initial angiogram, was detected on a subsequent angiogram 72 hours later.

INTERVENTION

All patients underwent successful surgical clipping of their aneurysms. Two cases required sacrificing of the parent vessels because of the friable nature of the false aneurysms. In each case, severe symptomatic vasospasm occurred, requiring angioplasty. All three patients also required a ventriculoperitoneal shunt for persistent hydrocephalus.

CONCLUSION

Features of these three cases and similar cases reported in the literature support the theory that vascular ruptures and traumatic aneurysms of the proximal PICA may be related to anatomic variability of the PICA as it transverses the brainstem. This variability predisposes individuals to vascular lesions, which occur in a continuum based on the severity of the injury. Posterior fossa subarachnoid hemorrhage after head injury requires a high index of suspicion and warrants aggressive diagnostic and therapeutic interventions.