Cavernous angioma presenting with subarachnoid hemorrhage which was diffusely distributed in the basal cisterns and mimicked intracranial aneurysm rupture

A Systematic Review and Case Illustrations of Misdiagnosing Intracranial Aneurysms

Modern neuroimaging methods do not completely rule out false diagnoses of intracranial aneurysms which can lead to an unwarranted operation associated with risks of complications. However, surgical interventions for falsely diagnosed aneurysms are quite rare. The purpose of this study is to demonstrate two clinical cases of false-positive aneurysms and a systematic review of the literature dedicated to the incidence and etiology of false-positive aneurysms, identifying risk factors associated with false-positive aneurysms. A literature search in two databases (PubMed and Web of Science) using keywords "mimicking an intracranial aneurysm", "presenting as an intracranial aneurysm", "false positive intracranial aneurysms", and "neurosurgery" was conducted. A total of 243 papers were found in the initial search in two databases. Sixteen papers (including 20 patients) were included in the final analysis. There were 10 women and 10 men. The most common location of false-positive aneurysms was the bifurcation of the middle cerebral artery (MCA). In the posterior circulation, false-positive aneurysms were identified either on the basilar artery, or at the vertebro-basilar junction. The main causes of false intracranial aneurysm diagnosis included artery occlusion with vascular stump formation, infundibular widening, fenestration, arterial dissection, contrast extravasation, and venous varix. In conclusion, summarizing the results of our analysis, we can say that surgical interventions for false-positive aneurysms are an underestimated problem in vascular neurosurgery. Despite extremely rare published clinical observations, the actual frequency of erroneous surgical interventions for false-positive aneurysms is unknown.

Subarachnoid Hemorrhage Caused by Supratentorial Cerebral Cavernous Malformation: A Case Report

Cavernous malformations (CMs) are acquired vascular abnormalities of the central nervous system that are typically asymptomatic. Clinically symptomatic lesions may present with seizures, intracerebral hemorrhage, or focal neurological deficits. Very rarely, CMs have been described as the cause of subarachnoid hemorrhage. We report a case of a previously healthy 58-year-old man who presented with acute onset of severe headache associated with vomiting. Head computed tomography (CT) scan showed subarachnoid hemorrhage with intraventricular extension. Subsequent CT angiography (CTA) and digital subtraction angiography (DSA) studies showed no evidence of vascular abnormalities. The patient was initially managed conservatively but later required neurosurgical and radiological interventions due to a complicated hospital course and worsening clinical condition. During surgery, an incidental mass was found in the temporal lobe, and subsequent histopathological examination confirmed the diagnosis of cavernoma, which was likely the underlying cause of the subarachnoid hemorrhage. This report highlights the importance of considering CMs in the differential diagnoses of subarachnoid hemorrhage, especially in the absence of informative results from CTA and DSA studies. Timely detection and management of CMs may positively impact the clinical outcome, leading to reduced morbidity and mortality rates.

Subarachnoid Hemorrhage due to Cerebral Cavernous Malformation in a Young Female

Cerebral cavernous malformations (CCMs) are usually intraparenchymal lesions commonly associated with intraparenchymal hemorrhage. Extra-axial Lesions are uncommon and have rarely been reported as the cause of aneurysmal like subarachnoid hemorrhage (SAH). We present a 33-years-old female with a past medical history significant for hypertension who presented with acute onset head and neck pain after bending over. En route to the hospital, she had abnormal motor movements suggestive of seizures. Computed tomography (CT) of the head was significant for diffuse aneurysmal like SAH. Head CT angiography (CTA) and catheter digital subtraction angiography (DSA) were both negative for aneurysm. Magnetic resonance imaging (MRI) of the brain showed susceptibility artifact in the right parafalcine frontal lobe suspicious for underlying CCM. This lesion was in the area suspected of having an aneurysm on CT head. The patient was diagnosed with SAH secondary to cavernous malformation mimicking aneurysmal etiology. This case is important as it serves as a good reminder to consider cavernous malformations in the differential in patients presenting with angiogram negative SAH. Diagnosis of this entity has treatment implications including discontinuation of calcium channel blockers if initiated, discussion about duration of anti-seizure medication, in addition to consideration for surgical intervention in select populations.

Intracranial varix of the transverse-sigmoid dural arteriovenous fistula mimicking a ruptured middle cerebral artery aneurysm: A case report

Background:

Hemorrhagic stroke is caused by various vascular abnormalities, such as aneurysms, arteriovenous malformations, and dural arteriovenous fistulas (DAVF). Magnetic resonance angiography (MRA) and three-dimensional computed tomography angiography (3DCTA) are used as efficient initial diagnostic modalities in assessing the etiology of hemorrhagic stroke. We describe the unusual case of a false-positive aneurysm on MRA and 3DCTA.

Case Description:

A 65-year-old nonhypertensive woman was brought to our hospital with a sudden onset of headache and left hemiparesis. She also had chemosis in the right eye. CT and magnetic resonance imaging showed an intracerebral hemorrhage in the right temporal lobe. MRA and 3DCTA showed a rounded mass suggestive of an aneurysm arising from the bifurcation of the middle cerebral artery (MCA) and also demonstrated an abnormal tortuous vessel contacting with a rounded mass. Digital subtraction angiography showed a transversesigmoid sinus DAVF with a varix in contact with the MCA bifurcation. Hematoma evacuation and venous drainage disconnection through the right frontotemporal craniotomy were performed.

Conclusion:

This case is very instructive and clinicians should keep in mind that detailed neurological and radiological examinations are essential in obtaining an accurate diagnosis, especially if the bleeding source is similar in shape and location to common lesions (such as a cerebral aneurysm).

Cerebral cavernous malformation in a child leading to a fatal subarachnoid hemorrhage - "silent but sinister:" A case report and literature review

Background:

Cerebral cavernous malformations (CCMs), otherwise known as cavernous hemangiomas/ cavernomas, are a type of vascular malformation. It is the third most common cerebral vascular malformation, histologically characterized by ectatic, fibrous, blood filled “caverns” with thin-walled vasculature without intervening normal brain parenchyma.

Case Description:

Herein, we present a case of an original, spontaneous hemorrhage from a sporadic form of CCM without associated gross developmental venous anomaly in an 11-year-old child, which is an extremely rare occurrence, with the special emphasis on the demographic data of the affected population, risk factors associated with hemorrhage, and correlation of histopathological and radiological findings with an in-depth literature review.

Conclusion:

The significant majority of the CCM are clinically occult. Hence, the development of risk assessment tools and guidelines for timely neurosurgical intervention poses a greater clinical challenge for medical experts rendering the management of the affected individuals with CCM in an anecdotal situation. Presentation of life-threatening rebleeds and neurological deficits in the diagnosed population albeit uncommon is possibly preventable outcomes.

De novo cavernous malformation arising in the wall of vestibular schwannoma following stereotactic radiosurgery: case report and review of the literature

We report a novel case of a radiation-induced cavernous malformation developing in a vestibular schwannoma previously treated with stereotactic radiosurgery. Eleven years after treatment, the patient presented with a large predominantly cystic lesion in the cerebellopontine angle. We performed surgery, and a solid vascular lesion was identified within the schwannoma, which was determined to be a cavernous malformation after histopathological analysis. We review the literature of radiation-induced cavernous lesions, illustrating that while rare, these lesions do pose concern as a long-term complication of brain radiation therapy. We also discuss the possibility that radiation-induced cavernous malformation-like lesions are pathologically distinct from cavernous malformations.