A ruptured aneurysm arising at the leptomeningeal collateral circulation from the extracranial vertebral artery to the posterior inferior cerebellar artery associated with bilateral vertebral artery occlusion

Surgical Treatment of Ruptured Aneurysms of Lateral Spinal Artery Presenting as Intracranial Subarachnoid Hemorrhage : Case Series and Literature Review

Lateral spinal artery (LSA) aneurysms are extremely rare lesions that can rupture and cause subarachnoid hemorrhage (SAH) even though the spinal arteries communicate directly with the subarachnoid space. To date, six cases of LSA aneurysms have been reported in the literature. Herein, three such cases are reported. All patients presented to the emergency department with headaches. The patients in the first two cases were confirmed to have SAH and LSA aneurysms on a brain computed tomography (CT) angiography performed at the hospital. Two patients had prior instances of cerebral infarction and coronary disease, respectively, and were undergoing antiplatelet therapy. The antiplatelet medication was stopped for 2 weeks and 1 week, respectively, while conservative care was provided. Subsequently, a suboccipital craniectomy was performed, followed by aneurysm clipping. Following the surgery, both patients were discharged without any significant neurological deficits. Regarding the third patient, no aneurysm was found on brain CT angiography, and cerebral angiography was performed during the patient's hospital stay. She was hospitalized, where she received medication and conservative care, and was discharged with an improvement in bleeding without neurological symptoms. Subsequently, a LSA aneurysm was identified on a brain CT angiography performed at an outpatient clinic; however, the patient was transferred because she wanted to be treated at another hospital. LSA aneurysms are difficult to visualize using CT angiography; therefore, careful angiographic studies are required. Surgical clipping is the treatment of choice if the aneurysm is inaccessible by the endovascular treatment.

Lateral Spinal Artery Aneurysm Causing Subarachnoid Hemorrhage: Literature Review and Case Report

Ruptured aneurysms of the lateral spinal artery (LSA) causing subarachnoid hemorrhage (SAH) are exceptionally rare. Unlike common aneurysms in the circle of Willis, LSA aneurysms present unique diagnostic and therapeutic challenges due to their complex anatomy. We reviewed the literature, examining case reports detailing LSA aneurysm occurrences, diagnoses, treatments, and complications, and our subsequent analysis highlights the clinical presentations, imaging findings, treatment methods, and anatomical features of the LSA. We identified 10 patients from 7 case reports of LSA aneurysm presenting with SAH, and combined with the present case, this comprised a total of 11 patients. An initial CT angiography identified LSA aneurysm in only 2 of 11 patients, while 5 cases were detected in transfemoral cerebral angiography. Seven patients had stenosis or occlusion of nearby arteries. Among the 10 patients treated, 7 underwent microsurgical clipping, and 3 had endovascular treatment; complications included PICA infarction and subdural hematoma. LSA aneurysms, though rare, should be considered in differential diagnoses of posterior fossa SAH. An accurate diagnosis often requires repeated imaging. It is proposed to individualize treatment strategies based on the unique anatomical structure and hemodynamic conditions of each patient, utilizing both endovascular and surgical approaches. Understanding the vascular anatomy and collateral pathways of the LSA is crucial for improving diagnostic accuracy and treatment outcomes.

Isolated Cervical Ruptured Radiculomedullary Artery Aneurysm Predominantly Presenting as Supratentorial Subarachnoid Hemorrhage: Case Report and Review of the Literature

A spinal artery aneurysm originating from the branch of the extracranial vertebral artery is uncommon. Most of them were finally diagnosed due to the evidence of infratentorial or spinal subarachnoid hemorrhage (SAH). Herein, we report an extremely rare case of a ruptured spinal artery aneurysm which predominantly presented with supratentorial SAH. A 68-year-old woman was initially revealed cranial computed tomographic angiographically negative SAH with a Hunt-Hess grade of 3, while the digital subtraction angiography confirmed an isolated radiculomedullary aneurysm arising from the medial ascending branch of V2 segment at C2 level. The patient underwent surgery in a hybrid operating room. She was originally attempted with coil embolization, but successful clipping of the aneurysm was achieved through unilateral laminectomy at last. Regrettably, the current case suffered a poor clinical outcome due to the complications caused by progressive cerebral vasospasm. In summary, angiogram is of great value for this rare kind of aneurysmal definitive diagnosis. A hybrid operating room may be a feasible choice for the ruptured spinal artery aneurysm.

Ruptured aneurysm arising at anterior spinal artery as the collateral circulation with bulbar artery supply to posterior inferior cerebellar artery treated by proximal occlusion and occipital artery-posterior inferior cerebellar artery bypass: a case report and literature review

The cases of aneurysms arising from collateral vessels that supply the posterior inferior cerebellar artery (PICA) are so exceptionally rare that there is no consensus on the optimal treatment. In this report, a patient was presented with subarachnoid hemorrhage caused by a fusiform aneurysm on the right anterior spinal artery, which formed an anastomosis network with bulbar artery and the vessels supplying to the right PICA. We chose to perform proximal occlusion on the anterior spinal and bulbar arteries, using occipital artery-PICA bypass. Our case was the first where proximal occlusion was used concurrently with vascular reconstruction to treat a ruptured aneurysm of collateral vessels supplying to PICA.

Clipping of Ruptured Aneurysm of Lateral Spinal Artery Associated with Anastomosis to Distal Posterior Inferior Cerebellar Artery: A Case Report

BACKGROUND

Arteries that anastomose with the posterior inferior cerebellar artery (PICA) can harbor aneurysms.

CASE DESCRIPTION

We present a case of a patient who suffered a subarachnoid hemorrhage as a result from an aneurysm on the left lateral spinal artery (LSA) that anastomosed to the PICA. The aneurysm was treated surgically, and the flow between the LSA and PICA was disrupted. The activated anastomotic network created a new anastomosis between the LSA and PICA, which was seen at 6 months' follow-up.

CONCLUSIONS

Careful follow-up is warranted in patients who have an activated anastomotic network because they can potentially develop aneurysms on newly created anastomoses.