Multiple aneurysms of the PICA communicating artery: a case report

A case with unusual type of aneurysms in the distal posterior inferior cerebellar artery (PICA) is reported here. Though only two cases with a single aneurysm of the PICA communicating artery have been reported previously, the present case is the first one with multiple aneurysms in the PICA communicating artery. A 61-year-old woman with a sudden onset of severe headache, vomiting and unconsciousness was transferred to our hospital. CT scan revealed a hematoma in the fourth, third, and lateral ventricles, and a mild subarachnoid hemorrhage at the posterior fossa. Cerebral angiogram showed the right PICA supplying the hypoplastic left PICA territory through an anastomotic vessel. Two small aneurysms were seen at the tips of hairpin curves of an anastomotic vessel, "the PICA communicating artery". Suboccipital craniotomy was performed, and the ruptured aneurysm was clipped and the unruptured one was wrapped with cotton-sheet. After the operation, her clinical recovery went well and she was discharged on foot.     

Bilateral mirror posterior inferior cerebellar artery aneurysms: diagnostic caveat on catheter angiography

Only three definitive cases of bilateral mirror proximal posterior inferior cerebellar artery (PICA) aneurysms have ever been reported. A fourth example is presented where each PICA aneurysm remained angiographically occult on contralateral vertebral artery angiography despite retrograde filling of the parent vessel PICA. Implications for clinical practice are discussed.     

Aneurysms of the distal posterior inferior cerebellar artery--analysis of 14 aneurysms in 13 cases

Thirteen cases of distal posterior inferior cerebellar artery (PICA) aneurysms are reported here. All the aneurysms were found after a subarachnoid hemorrhage. Dissecting aneurysm, incidentally found unruptured aneurysms, and aneurysms associated with arteriovenous malformation have been eliminated from this study. Characteristics for this type of lesion are a high rate of recurrent hemorrhage and rapid death due to direct compression of the brain stem, which clearly indicates the necessity of early surgery. Attention should be paid to the fact that angiography cannot always reveal aneurysms, especially when they are located in the peripheral PICA. One should also pay attention to multiple lesions and rapid growing acute subdural hematoma as initial findings for ruptured distal PICA aneurysm. Prognostic factors for these lesions are, vasospasm, especially when the aneurysm is located proximally in the PICA, and direct compression of the brain stem due to intraventricular hemorrhage when the aneurysm is located distally. It has been suggested that the pathogenesis of this lesion could be hemodynamic stress or embryogenesis. The shape and anomalous arterial structures of the 14 aneurysms presented here tend to agree with this suggestion. Our results suggest that the pathogenesis is hemodynamic stress that had developed due to embryological and/or arteriosclerotic factors.     

Distal aneurysm of the posterior inferior cerebellar artery--report of 3 cases

The incidence of posterior fossa aneurysm is reported to be 4-15% of all intracranial aneurysms in large series. Most aneurysms of the posterior inferior cerebellar artery (PICA) arise at the origin of the PICA. However, aneurysms of the distal part of the PICA have only rarely been described. This report presents three cases of distal PICA aneurysm with subarachnoid hemorrhage. Two aneurysms were located in the superior retrotonsillar segment of the PICA in two cases, and another was located in the tonsillohemispheric branch in one case. Obliteration of these aneurysms was comparatively easily done by bilateral suboccipital craniectomy. Computerized tomography (CT) was done in two cases. CT scan of the second case revealed a hematoma in the cerebellar vermis, and that of the third case revealed hemorrhage in the fourth and third ventricles. These findings seem to be common in subarachnoid hemorrhage of this lesion and may suggest the rupture of distal PICA aneurysm.     

A dissecting aneurysm of the posterior inferior cerebellar artery was reduced spontaneously during conservative therapy: case report

We report here a case of a patient with a dissecting aneurysm of the anterior medullary segment of the posterior inferior cerebellar artery (PICA) which presented with Wallenberg's syndrome. A 32-year-male presented with an unusual case of Wallenberg's syndrome due to a dissecting aneurysm of the PICA manifesting as a sensation of heaviness in the occipital region and vertigo. The occipital symptoms persisted and vertigo and vomiting developed after 6 days. Numbness developed on the left side of the patient's face, and hyperalgesia on the right side of the body. The diagnosis of Wallenberg's syndrome was based on the above findings. MRI revealed infarction of the lateral aspect of the medulla oblongata and MR angiography revealed dilatation in the proximal portion of the left PICA. Digital subtraction angiography revealed that the left vertebral artery was essentially normal, but there was a spindle-shaped dilatation in the proximal portion of the left PICA. We carried out conservative therapy at the patient's request and 3D-CTA revealed that the dissecting aneurysm was markedly reduced in size seven months after the onset. Dissecting aneurysms of the intracranial posterior circulation have been shown to be less uncommon than previously thought. However, those involving the PICA without involvement of the vertebral artery at all are extremely rare. The natural history of the dissecting PICA aneurysm was unknown, and the indication for surgical treatment of such aneurysms remains controversial. Management options are conservative treatment, open surgical treatment including wrapping, trapping, and resection with reconstruction, but almost all of the patients underwent radical treatment to prevent rupture of the aneurysm. However we had no knowledge of the risk of rupture of a PICA dissecting aneurysm presenting with ischemic symptoms. We have reviewed the well-documented 15 cases of dissecting aneurysms of the PICA reported in the literature and we discuss the management of the dissecting PICA aneurysm presenting with ischemic symptoms.     

Growth of multiple peripheral high flow aneurysms of the posterior inferior cerebellar artery associated with a cerebellar arteriovenous malformation

A case of three high flow peripheral aneurysms of the posterior inferior cerebellar artery (PICA) associated with a left cerebellar arteriovenous malformation is presented. This rare association is of further interest because the patient had been diagnosed as harboring an arteriovenous malformation 3 years before her most recent subarachnoid hemorrhage. Repeat angiography revealed enlargement of the malformation with new growth of three peripheral PICA aneurysms at the telovelotonsillar segment. Successful excision of the malformation and obliteration of all three aneurysms were accomplished. The causal mechanism of increased cerebral blood flow in the generation of the peripheral cerebral aneurysms is demonstrated.     

Computed tomographic diagnosis of ruptured giant posterior cerebral artery aneurysms

Ruptured giant posterior cerebral artery (PCA) aneurysms are encountered rarely. Although computed tomographic (CT) scan features of giant intracranial aneurysms have been described. CT scan features of acutely ruptured giant saccular PCA aneurysms have not been reported. A case of an acutely ruptured giant saccular PCA aneurysm with diagnostic CT scan features and autopsy confirmation is presented. Two additional cases of apoplexy with identical clinical courses and CT scan appearances, both attributed to giant saccular PCA aneurysms, are described. Diagnostic CT scan features included evidence of intraparenchymal temporal lobe and intraventricular hemorrhage, the presence of a filling defect in the temporal lobe hematoma that enhanced after intravenous contrast administration, and evidence of proximal PCA entrance into the contrast-enhanced filling defect in the intracerebral hematoma. The incidence of PCA aneurysms and the anatomy of the PCA as it relates to these giant aneurysms, their clinical presentation, and diagnostic features of the CT scan are discussed.     

Multiple aneurysms of the distal posterior inferior cerebellar artery with recurrent hemorrhage undetectable on preoperative neuroradiological findings: case report

We report a rare case of multiple aneurysms of the distal posterior inferior cerebellar artery (PICA) associated with recurrent hemorrhage undetectable on preoperative neuroradiological findings. A 68-year-old woman was admitted to our hospital in April, 2003 because of a sudden onset of headache, back neck pain and nausea. CT scan at the time of admission showed a hematoma in the 4th & 3rd ventricles, and a mild subarachnoid hemorrhage (SAH) in the basal, right ambient & quadrigeminal cisterns. She had had a similar history of previous intraventricular hemorrhage and SAH in October, 2001. Three-dimensional CT angiograms and left vertebral angiograms performed at that time revealed an irregular vascular lesion at the tonsillomedullary segment (TMS) of the left PICA. However, the final diagnosis was unclear. Left vertebral angiograms at the time of the 2003 admission revealed an irregular vascular lesion in the same region more clearly and the size of aneurysmal dilatations had increased considerably. So, preoperative diagnosis of an irregular vascular lesion at the TMS of the left PICA (distal PICA aneurysm was not ruled out) was based on the above neuroradiological findings. The patient was surgically treated through the suboccipital approach. The TMS of the left PICA had made a difficulty loop formation was observed. Five distinct aneurysma were found on the TMS of the left PICA. To prevent bleeding, the ruptured aneurysm & three unruptured aneurysms were clipped and the residual unruptured one was wrapped with Bemsheets. Postoperative left vertebral angiograms demonstrated neither clipped aneurysms nor occlusive findings at the TMS of the PICA. The patency of the PICA was preserved. The postoperative course was uneventful and the patient was discharged without new neurological deficits. There has been no rebleeding during the one year since surgery. The 23 reported cases of multiple aneurysms of the distal PICA including our case were reviewed and their neuroradiological and clinical features are discussed.     

Ruptured aneurysms of the choroidal branches of the posterior inferior cerebellar artery: a review of the literature and a case report

Aneurysms of the choroidal branches of the posterior inferior cerebellar artery (PICA) are quite rare; only seven such cases have been reported thus far. In this study, we present a very rare case of a ruptured aneurysm of a choroidal branch of the PICA; the aneurysm was exposed by splitting the vermis and resected after proximal arterial ligation. We have also undertaken a thorough review of the literature on aneurysms in choroidal branches of the PICA, focusing on the clinical presentation, etiology, radiological findings, and surgical strategies. We found that the aneurysms in our patient and the aneurysms in seven published case reports were small, and frequently associated with vascular anomalies. Intraventricular hemorrhage (IVH) in the fourth ventricle was detected in all eight cases. The outcomes of surgical treatment were generally favorable, notwithstanding the high incidence of rebleeding after rupture of distal PICA aneurysms. The recognition of predominant fourth ventricular hemorrhage should raise the suspicion of the presence of an underlying aneurysm, and digital subtraction angiograms (DSAs) should be immediately obtained in order to detect small aneurysms of the choroidal branches of the PICA.     

Dissecting aneurysms of the vertebral artery: a management strategy

OBJECT: The authors present a retrospective analysis of their experience in the treatment of vertebral artery (VA) dissecting aneurysms and propose a management strategy for such aneurysms, with special emphasis on the most formidable VA dissecting aneurysms, which involve the origin of the posterior inferior cerebellar artery (PICA). METHODS: Since 1998, 18 patients with VA dissecting aneurysms, 11 of whom presented with subarachnoid hemorrhage (SAH), have been treated by endovascular surgery at the authors' institution. Obliteration of the entire segment of the dissected site with coils (internal trapping) was performed for aneurysms without involvement of the origin of the PICA (12 cases; among these the treatment-related morbidity rate was 16.7%). The treatment strategy applied to PICA-involved VA dissecting aneurysms presenting with SAH (three cases) included proximal occlusion of the parent artery followed by internal trapping of the aneurysm (one case), proximal occlusion of the parent artery followed by occipital artery (OA)-PICA bypass (one case), and two-staged internal trapping of the aneurysm involving double PICAs (one case). For PICA-involved VA dissecting aneurysms that were not associated with SAH at presentation (three cases), OA-PICA bypass was performed and followed by internal trapping of the aneurysm (two cases). In the remaining case in which a fetal-type posterior communicating artery was present, internal trapping was performed following successful balloon test occlusion (BTO). Overall, there was no sign of infarction in the PICA territory, despite complete occlusion of aneurysms involving the PICA. There was no recurrent bleeding or ischemic symptoms during the follow-up periods. The overall treatment-related morbidity rate for the VA dissecting aneurysms involving the PICA was 16.7%. CONCLUSIONS: Dissecting VA aneurysms that do not involve the PICA can be safely treated by internal trapping. For those lesions that do involve the PICA, a decision-making algorithm is advocated to maximize the efficacy of the treatment as well as to minimize the risks of treatment-related morbidity based on BTO.     

Surgical management of ruptured and unruptured symptomatic posterior inferior cerebellar artery aneurysms

This retrospective study analyses the outcome of posterior inferior cerebellar artery aneurysms treated surgically. Thirteen consecutive ruptured and unruptured PICA aneurysm patients from January 1998 to January 2004 were reviewed retrospectively. The mean age was 49.1 +/- 7.4 years. Three were unruptured aneurysms and ten presented with acute subarachnoid haemorrahge. Surgery was performed immediately after completed 4 vessel angiograms using the far lateral approach. Eight were fusiform while five were saccular aneurysms. The saccular aneurysms were clipped. Treatment of the fusiform aneurysms included 3 trappings and three proximal clippings. One patient refused surgery and had endovascular occlusion of a giant PICA aneurysm. Eight out of ten (80%) operated patients needed CSF shunting for hydrocephalus. All check angiograms during follow up demonstrated adequate exclusion of the aneurysms from the circulation. None developed the PICA syndrome clinically or showed infarction on brain scans. All good grade patients recovered without neurological deficits. Our experience showed that early surgery for ruptured PICA aneurysm carries a good prognosis with low morbidity. In aneurysms that cannot be clipped, sacrifice of the PICA without revascularisation procedures in proximally located PICA aneurysms may still be feasible if the occlusion is done distal to the perforators.     

A "PICA communicating artery" aneurysm: case report.

We present an unusual case of an aneurysm of the distal posterior inferior cerebellar artery (PICA). The aneurysm was associated with a unilateral PICA that supplied both cerebellar hemispheres and arose from an anastomotic vessel to the contralateral circulation, a branch of the contralateral PICA. Such an aneurysm has not been reported previously. The associated of vascular anomalies with aneurysms of the PICA is discussed.     

Giant basilar artery aneurysm presenting as a third ventricular tumor

Giant aneurysm of the basilar artery presenting as a 3rd ventricular tumor is an unusual phenomenon. We are reporting a case in which a patient with a giant aneurysm of the basilar artery presented with symptoms of headaches and gait disturbance secondary to obstructive hydrocephalus. Although giant aneurysms presenting as mass lesions have been reported, the computed axial tomographic findings in our case were unique. Giant aneurysms of the basilar artery may be considered in the differential diagnosis of 3rd ventricular tumors.     

Fenestration of the posteroinferior cerebellar artery: case report

OBJECTIVE AND IMPORTANCE: Fenestrations of cerebral arteries are rare, but very important to diagnose given their high association with saccular aneurysms. We present the first reported case of a fenestration of the posteroinferior cerebellar artery (PICA). CLINICAL PRESENTATION: A 62-year-old man who presented with a subarachnoid hemorrhage underwent repeated four-vessel cerebral angiography. An isolated right PICA abnormality consistent with a dissection or fenestration was revealed. INTERVENTION: The patient underwent surgical exploration of his PICA, which confirmed a PICA fenestration without an associated saccular aneurysm. The fenestration was wrapped with cotton. CONCLUSION: Our case report illustrates the novel anatomic finding of a fenestration of the PICA. Knowledge of this entity would be helpful in the differential diagnosis of a posterior fossa subarachnoid hemorrhage.     

Giant serpentine aneurysm in a long-term hemodialysis patient

A long-term hemodialysis patient with a giant intracranial vascular channel, which has been called a giant serpentine aneurysm, is presented. A 50-year-old man with an eight-year history of hemodialysis treatment was admitted because of headache, nausea and double vision. Computed tomographic scans and nuclear magnetic resonance revealed intracranial abnormal shadow. The left vertebral arteriography showed that the distal portion of the left vertebral artery was dilated to 17 mm in diameter. The basilar artery showed a large tortuous vascular channel and globular aneurysms over 25 mm in diameter. This giant serpentine aneurysm is a rather rare disease. To our knowledge, it has not been reported as a complication in a hemodialysis patient, although fourteen cases have been reported in the literature. In our case, several conditions such as long-term hypertension, hyperlipidemia, hypercalcemia, atherosclerosis and abnormal blood flow due to arteriovenous fistula for hemodialysis treatment might be considered to play a role in the formation of the giant serpentine aneurysms.     

Multiple giant fusiform aneurysms with hydrocephalus

Multiple giant fusiform aneurysms are uncommon. We report such a case of multiple giant fusiform aneurysms involving both internal carotid arteries and the basilar artery associated with hydrocephalus. The neurological deficits presented in this case were due to pontine infarction, which was suspected to be produced by thrombosis from the aneurysm, and a hydrocephalus might have been caused by a "water-hammering" effect of the elongated basilar artery.     

Peripheral PICA aneurysm. Case report

One case of aneurysm of the right distal posterior inferior cerebellar artery (PICA), arising from the telo-velo tonsillary segment, is reported; the patient, a 73 years-old woman, was successfully treated by clipping procedure. Few similar cases are reported in literature. Among all intracranial aneurysms, PICA aneurysms account for 0.5-0.7%; most of them arise from vertebro-basilar junction, while only 72 distal PICA aneurysms are reported in literature, till now, with complete anatomo-radiological study. We recommend four vessel angiography because these aneurysms are likely to be missed. When determining the surgical approach it is important to know from which segment the aneurysm arises.     

Dissecting Aneurysm of the Peripheral Posterior Inferior Cerebellar Artery

Dissecting aneurysms of intracranial posterior circulation have recently been shown to be less uncommon than previously thought. However, those involving the posterior inferior cerebellar artery (PICA) and not vertebral artery at all are extremely rare. We report here a case of a patient with a dissecting aneurysm of the lateral medullary segment of PICA which presented as subarachnoid haemorrhage. The aneurysm was treated by trapping surgery and the distant PICA was anastomosed to the occipital artery. The patient showed a slight ataxia immediately after surgery but recovered fully. Recovery from immediately postoperative cerebellar symptoms due to intra-operative ischemia seemed to be due largely to recovery of flow in the region of cortical branches of PICA.     

Pituitary tumors and aneurysms: case report and review of the literature.

A case of acromegaly from a growth hormone-secreting pituitary adenoma associated with dilatation of all major intracranial arteries and bilateral giant, cavernous aneurysms is presented. Although saccular aneurysms are randomly associated with all types of pituitary tumors, the frequency of this happening with growth hormone-secreting or "chromophobe adenomas" is greater than would be expected by chance alone. Intrasellar saccular aneurysms contiguous with tumors have been reported. Bilateral cavernous carotid aneurysms have also occurred in association with pituitary tumors. Both infectious (bacterial and fungal) and traumatic aneurysms can develop as complications of pituitary surgery. A single case of aneurysms due perhaps to actual tumor infiltration of the arterial wall has been reported. Radiation therapy has rarely been associated with aneurysmal dilatation for nonpituitary tumors and has been reported only once after treatment of a pituitary tumor. Aneurysms may mimic pituitary tumors by producing endocrine disturbances, such as hypopituitarism, hyperprolactinemia, and diabetes insipidus, and by compressing adjacent cranial nerves. Anomalous large arteries, such as the trigeminal or transsellar-carotid variants, may run through the sella, and there is a case reported in which the former was associated with a pituitary tumor. A knowledge of these aneurysmal types and vascular anomalies is essential for the pituitary surgeon. Magnetic resonance imaging is now the radiological procedure of choice in the preoperative assessment of patients suspected of having pituitary tumors or recurrences, because, in addition to depicting the tumor, it defines the arterial anatomy and excludes all but very small coexistent aneurysms.     

A growing aneurysm of the posterior inferior cerebellar artery complicated with cerebellar infarction: A case report

Introduction and importanceHereby we describe an instructive patient with cerebellar infarction and a growing aneurysm at the posterior inferior cerebellar artery (PICA), which was not a true cause of infarction.Case presentationA 50-year-old female presented with dizziness and posterior neck pain at our hospital (Mitaka city, Tokyo, Japan). Diffusion weighted magnetic resonance (MR) images showed cerebellar infarction in the left PICA territory and MR angiography study showed an aneurysm at the origin of the left PICA, which grew in 2 weeks. Since we considered cerebellar infarction was caused by thrombosis from the aneurysm, trapping of the PICA and occipital artery-PICA bypass was performed to prevent recurrent cerebellar infarction and rupture of the aneurysm by neurosurgeons. During the operation, dissection was observed at the distal PICA, which was diagnosed to be the true cause of cerebellar infarction. By the follow-up for 12 months at an outpatient, there was no recurrence of cerebral infarction.Clinical discussionA specimen of the artery showing the findings of dissection was not obtained, and the pathological diagnosis could not be made. It would be controversial whether a surgical procedure presented here was the most optimal.ConclusionThis is a first reported case of growing aneurysms and cerebral infarction due to arterial dissection. Even if cerebral infarction is accompanied by growing aneurysms, arterial dissection should be included in the differential diagnoses of a cause of infarction. Posterior cervical pain can be a clue for early appropriate diagnosis in such a case.