Idiopathic lenticulostriate artery pseudoaneurysm protruding into the lateral ventricle: a case report

Aneurysm of Distal Medial Lenticulostriate Artery: Report of 2 Cases

BACKGROUND

Aneurysms originating from the distal portion of the lenticulostriate artery (LSA) are uncommon. Distal medial LSA (MLSA) aneurysms are particularly uncommon when compared with distal lateral LSA aneurysms, and their clinical features are unclear. Here, we present 2 patients with aneurysms of the distal MLSA who exhibited hemorrhages of the caudate nucleus and intraventricular region (intraventricular hemorrhage [IVH]).

CASE DESCRIPTION

Patient 1 is a 50-year-old woman who was admitted to our hospital because of a hemorrhage in the left caudate nucleus and ventricles. She underwent external ventricular drainage (EVD). Cerebral angiography (CAG) performed on hospital day 24 showed an aneurysm located in the distal portion of the MLSA; however, CAG performed on admission revealed no abnormal vessels. We excised the aneurysm using a transcallosal-transventricular approach. Patient 2 is an 88-year-old woman who was admitted to our hospital with a right caudate nucleus hematoma and a dense IVH. She underwent emergent EVD. CAG demonstrated a 2.5-mm aneurysm in the distal MLSA, and a 6-mm aneurysm which originated from the right horizontal portion of the anterior cerebral artery (A1)-MLSA bifurcation aneurysm. We performed direct clipping of the A1-MLSA bifurcation aneurysm with proximal ligation of the distal MLSA aneurysm.

CONCLUSIONS

We should consider the possibility of a ruptured distal MLSA aneurysm when diagnosing a patient with IVH-with or without a caudate nucleus hematoma. Repeated imaging evaluations may be necessary to find the lesion.

A Patient with a Distal Medial Lenticulostriate Artery Aneurysm and Intraventricular Hemorrhage Treated by Endovascular Treatment

Objective

A patient with a ruptured distal medial lenticulostriate artery (mLSA) aneurysm presenting with intraventricular hemorrhage was successfully treated using endovascular treatment.

Case Presentation

A 60-year-old woman presented with impaired consciousness. Radiological examination revealed intraventricular hemorrhage caused by a rupture of a distal mLSA aneurysm. Using endovascular technique, approaching contralaterally through the anterior communicating artery (AComA), complete occlusion of the aneurysm was achieved by N-butyl-2-cyanoacrylate (NBCA) injection. The postoperative course was uneventful.

Conclusion

Intraventricular aneurysms at a distal site of the perforating arteries are rare. Although there have been reports on patients with distal mLSA aneurysms treated by open surgery or conservative therapy, endovascular therapy should also be considered as a treatment option.

Massive intracranial bleeding due to the rupture of a rare spontaneous pseudoaneurysm of the middle cerebral artery in a pediatric patient: case report with clinical, radiological, and pathologic findings

Intracranial pseudoaneurysm (IPA) is a rare but likely underdiagnosed cause of intracranial hemorrhage, which accounts for just 1-6% of all intracranial aneurysms. Spontaneous IPAs are exceptionally rare, and their etiology and features are not well defined. Herein, we report a case of a pediatric patient who died from massive intracranial bleeding due to the rupture of a spontaneous IPA after undergoing multiple radiological studies and neurosurgical operations. At the postmortem examination of the brain, a giant size pseudoaneurysm of the right middle cerebral artery was observed. Microscopic examination demonstrated variable wall thickness and dense fibrosis focally in the vessel wall with disruption of the media structure together with a loss and fragmentation of the elastic laminae, loss of organization of smooth muscle cells in the media, and multifocal areas of hemorrhage throughout the vessel wall, as well as direct evidence of wall dissection. Since IPAs without any traumatic or infective history are extremely uncommon, further pathologic studies should be performed to clarify spontaneous pseudoaneurysm etiology.

Aneurysm of lenticulostriate artery in a patient presenting with hemorrhage in the caudate nucleus and lateral ventricle-delayed appearance and spontaneous resolution

Background:

An aneurysm of distal lenticulostriate artery is very rare. The natural course and management of this rare aneurysm are not clear.

Case Description:

An 81-year-old woman developed consciousness disturbance. Computed tomography revealed hemorrhage in the right caudate nucleus and lateral ventricles. Three-dimensional computed tomographic angiography demonstrated only an aneurysm at the basilar artery. On angiography, on the sixth day, an aneurysm at the right lenticulostriate artery was demonstrated. Then, the aneurysm disappeared on three-dimensional computed tomographic angiography on the 15^th day. Subsequent radiological examinations revealed no vascular anomaly in the right lenticulostriate artery.

Conclusion:

An aneurysm at this location can show dynamic changes based on radiological findings. Close radiological observation is necessary.

Successful Resection of a Growing Distal Medial Lenticulostriate Artery Pseudoaneurysm Presenting with Isolated Intraventricular Hemorrhage

INTRODUCTION

Distal medial lenticulostriate artery (LSA) aneurysms associated with isolated intraventricular hemorrhage (IVH) are extremely rare. We report a very rare case of the isolated IVH due to the rupture of the distal medial LSA pseudoaneurysm that was not visible at the initial angiography but later emerged and grew.

CASE REPORT

A 61-year-old woman with a history of hypertension had sudden onset of severe headache and mild consciousness disturbance. The computed tomography scan revealed the IVH, but the initial angiographies showed no evidence of aneurysm. The follow-up magnetic resonance imaging revealed that an intraventricular mass, arising from the right distal medial LSA, emerged and grew into the right anterior horn. Considering the risk of rebleeding, we resected the mass lesion via the transsulcal transventricular approach. The postoperative imaging showed complete obliteration of the mass lesion. Histopathological analysis indicated the pseudoaneurysm. The patient was discharged without any neurological deficit.

CONCLUSIONS

The careful and repetitive follow-up imaging should be done in the cases with isolated IVH even if the initial image evaluations are unrevealing. The transsulcal transventricular approach can be the most minimally invasive surgical option for intraventricular lesion.

Nontraumatic, posterior circulation pseudoaneurysm of the basilar artery summit with complete spontaneous resolution: Case report and literature review

Background:

Intracranial pseudoaneurysms are rare vascular defects of arterial walls that are classically the result of traumatic injury, iatrogenic causes, or infection. Idiopathic pseudoaneurysms are seen even less frequently and are often related to atherosclerosis. Pseudoaneurysms are most commonly found along the distal wall of the internal carotid artery, however, can occur at any location in the cerebrovascular circulation. Treatment of these arterial defects is often challenging due to their frail nature.

Case Description:

A 61-year-old male with a history of hypertension presented with a severe, atypical headache without history of trauma. Computed tomography (CT) and computed tomography angiography (CTA) demonstrated diffuse subarachnoid hemorrhage. Imaging demonstrated a 3.5 mm pseudoaneurysm projecting distally from the basilar artery at the apex. Repeated imaging (CTA, digital subtraction angiography) demonstrated decreased size and flow associated within the aneurysm over the following 2 weeks; as such, the patient was managed conservatively. The patient was discharged in neurologically intact condition when imaging at 14 days confirmed complete and spontaneous resolution of the pseudoaneurysm.

Conclusion:

Idiopathic pseudoaneurysms that are commonly associated with atherosclerosis are most commonly managed surgically or endovascularly. Conservative approach may be considered in a select group of patients that exhibit decreased size and/or flow within the aneurysm in repeated imaging; spontaneous resolution was seen in the present case.