OBJECTIVE: Cerebral aneurysms (CAs) and abdominal aortic aneurysms (AAAs) are degenerative vascular pathologies that manifest as abnormal dilations of the arterial wall. They arise with different morphologies in different types of blood vessels under different hemodynamic conditions. Although treated as different pathologies, we examine common pathways in their hemodynamic pathogenesis in order to elucidate mechanisms of formation. MATERIALS AND METHODS: A systematic review of the literature was performed. Current concepts on pathogenesis and hemodynamics were collected and compared. RESULTS: CAs arise as saccular dilations on the cerebral arteries of the circle of Willis under high blood flow, high wall shear stress (WSS), and high wall shear stress gradient (WSSG) conditions. AAAs arise as fusiform dilations on the infrarenal aorta under low blood flow, low, oscillating WSS, and high WSSG conditions. While at opposite ends of the WSS spectrum, they share high WSSG, a critical factor in arterial remodeling. This alone may not be enough to initiate aneurysm formation, but may ignite a cascade of downstream events that leads to aneurysm development. Despite differences in morphology and the structure, CAs and AAAs share many histopathological and biomechanical characteristics. Endothelial cell damage, loss of elastin, and smooth muscle cell loss are universal findings in CAs and AAAs. Increased matrix metalloproteinases and other proteinases, reactive oxygen species, and inflammation also contribute to the pathogenesis of both aneurysms. CONCLUSION: Our review revealed similar pathways in seemingly different pathologies. We also highlight the need for cross-disciplinary studies to aid in finding similarities between pathologies.
Aneurysm ; Aorta ; Aortic Aneurysm, Abdominal* ; Blood Vessels ; Cerebral Arteries ; Circle of Willis ; Elastin ; Endothelial Cells ; Hemodynamics* ; Inflammation ; Intracranial Aneurysm ; Matrix Metalloproteinases ; Myocytes, Smooth Muscle ; Pathology ; Peptide Hydrolases ; Reactive Oxygen Species

Rupture of isolated posterior spinal artery (PSA) aneurysms is a rare cause of subarachnoid hemorrhage (SAH) that presents unique diagnostic challenges owing to a nuanced clinical presentation. Here, we report on the diagnosis and management of the first known case of an isolated PSA aneurysm in the context of leukocytoclastic vasculitis. A 53-year-old male presented to an outside institution with acute bilateral lower extremity paralysis 9 days after admission for recurrent cellulitis. Early magnetic resonance imaging was read as negative and repeat imaging 15 days after presentation revealed SAH and a compressive spinal subdural hematoma. Angiography identified a PSA aneurysm at T9, as well as other areas suspicious for inflammatory or post-hemorrhagic reactive changes. The patient underwent a multilevel laminectomy for clot evacuation and aneurysm resection to prevent future hemorrhage and to establish a diagnosis. The postoperative course was complicated by medical issues and led to the diagnosis of leukocytoclastic vasculitis that may have predisposed the patient to aneurysm development. Literature review reveals greater mortality for cervical lesions than thoracolumbar lesions and that the presence of meningitic symptoms portents better functional outcome than symptoms of cord compression. The outcome obtained in this case is consistent with outcomes reported in the literature.
Aneurysm* ; Angiography ; Arteries* ; Cellulitis ; Diagnosis ; Hematoma, Subdural, Spinal ; Hemorrhage ; Humans ; Laminectomy ; Lower Extremity ; Magnetic Resonance Imaging ; Male ; Middle Aged ; Mortality ; Paralysis ; Rupture ; Spinal Cord Vascular Diseases ; Subarachnoid Hemorrhage ; Vasculitis* ; Vasculitis, Leukocytoclastic, Cutaneous

Intracranial hypotension (IH) can occur following lumbar drainage for clipping of an intracranial aneurysm. We observed 3 cases of IH, which were all successfully treated by epidural blood patch (EBP). Herein, the authors report our cases.
Blood Patch, Epidural* ; Cerebrospinal Fluid* ; Drainage* ; Intracranial Aneurysm* ; Intracranial Hypotension* ; Retrospective Studies*

Background: and Purpose Randomized trials proved the benefits of mechanical thrombectomy (MT) for select patients with large vessel occlusion (LVO) within 24 hours of last-known-well (LKW). Recent data suggest that LVO patients may benefit from MT beyond 24 hours. This study reports the safety and outcomes of MT beyond 24 hours of LKW compared to standard medical therapy (SMT). Methods: This is a retrospective analysis of LVO patients presented to 11 comprehensive stroke centers in the United States beyond 24 hours from LKW between January 2015 and December 2021. We assessed 90-day outcomes using the modified Rankin Scale (mRS). Results: Of 334 patients presented with LVO beyond 24 hours, 64% received MT and 36% received SMT only. Patients who received MT were older (67±15 vs. 64±15 years, P=0.047) and had a higher baseline National Institutes of Health Stroke Scale (NIHSS; 16±7 vs.10±9, P<0.001). Successful recanalization (modified thrombolysis in cerebral infarction score 2b-3) was achieved in 83%, and 5.6% had symptomatic intracranial hemorrhage compared to 2.5% in the SMT group (P=0.19). MT was associated with mRS 0–2 at 90 days (adjusted odds ratio [aOR] 5.73, P=0.026), less mortality (34% vs. 63%, P<0.001), and better discharge NIHSS (P<0.001) compared to SMT in patients with baseline NIHSS ≥6. This treatment benefit remained after matching both groups. Age (aOR 0.94, P<0.001), baseline NIHSS (aOR 0.91, P=0.017), Alberta Stroke Program Early Computed Tomography (ASPECTS) score ≥8 (aOR 3.06, P=0.041), and collaterals scores (aOR 1.41, P=0.027) were associated with 90-day functional independence. Conclusion In patients with salvageable brain tissue, MT for LVO beyond 24 hours appears to improve outcomes compared to SMT, especially in patients with severe strokes. Patients’ age, ASPECTS, collaterals, and baseline NIHSS score should be considered before discounting MT merely based on LKW.

Background: and Purpose Outcomes following mechanical thrombectomy (MT) are strongly correlated with successful recanalization, traditionally defined as modified Thrombolysis in Cerebral Infarction (mTICI) ≥2b. This retrospective cohort study aimed to compare the outcomes of patients with low Alberta Stroke Program Early Computed Tomography Score (ASPECTS; 2–5) who achieved mTICI 2b versus those who achieved mTICI 2c/3 after MT. Methods: This study utilized data from the Stroke Thrombectomy and Aneurysm Registry (STAR), which combined databases from 32 thrombectomy-capable stroke centers between 2013 and 2023. The study included only patients with low ASPECTS who achieved mTICI 2b, 2c, or 3 after MT for internal carotid artery or middle cerebral artery (M1) stroke. Results: Of the 10,229 patients who underwent MT, 234 met the inclusion criteria. Of those, 98 (41.9%) achieved mTICI 2b, and 136 (58.1%) achieved mTICI 2c/3. There were no significant differences in baseline characteristics between the two groups. The 90-day favorable outcome (modified Rankin Scale score: 0–3) was significantly better in the mTICI 2c/3 group than in the mTICI 2b group (adjusted odds ratio 2.35; 95% confidence interval [CI] 1.18–4.81; P=0.02). Binomial logistic regression revealed that achieving mTICI 2c/3 was significantly associated with higher odds of a favorable 90-day outcome (odds ratio 2.14; 95% CI 1.07–4.41; P=0.04). Conclusion In patients with low ASPECTS, achieving an mTICI 2c/3 score after MT is associated with a more favorable 90-day outcome. These findings suggest that mTICI 2c/3 is a better target for MT than mTICI 2b in patients with low ASPECTS.