Intracranial Aneurysms Mimicking Third Ventricular and adjoining parts Masses Associated with Obstructive Hydrocephalus: Diagnosis and Treatment

Abstract Objective: Intracranial aneurysms presenting as third ventricular and adjoining parts masses are rare, and always associated with obstructive hydrocephalus. It is vital to provide precise diagnostics, and prompt treatment for such patients since endovascular or microsurgical operations remain challenging. This study aimed to discuss differential diagnosis tactic based on collected cases and the current literature on intracranial aneurysms mimicking third ventricular masses, and a treatment regimen based on the available data is proposed.Methods: We collected a case series of intracranial aneurysms presenting as third ventricular masses with hydrocephalus from our hospital database. Literature reports related to aneurysms adjoining the third ventricle since 1979 were also included.Results: Twenty-seven cases of this disease were collected. The average age of the patients was 62 years (range, 14–82 years). The female-to-male ratio of the patients was 14:13. Eight of the 27 patients died during hospitalization. Basilar artery aneurysm was the most common type (21 of 27 cases). One aneurysm from our cases was considered as a craniopharyngioma according to MRI report. There are false negative angiography reports for aneurysms from our cases and literature review. Strategies for the diagnosis and treatment of these aneurysms have changed over time. The uniqueness of our cases sheds light on the use of CT angiography, which has proven to be an appropriate test for diagnosis and reexamination but was not wildly applied in previous reports.Conclusions: Thrombosed aneurysms should be considered a differential diagnosis in patients with third ventricular masses. Application of CTA and VW-MRI can be beneficial. Aneurysm coil occlusion might be a favorable treatment for cases with mass effect. Further studies should be conducted to confirm our observations.