ABSTRACT
BACKGROUND: Collateral circulation is an important determinant of outcome in people with acute ischemic stroke due to large vessel occlusion (LVO). OBJECTIVE: To explore the impact of the circle of Willis (CW) anatomical characteristics ipsilateral to the occlusion site, particularly the posterior communicating artery (PComA) and the A1-portion of the anterior cerebral artery (A1-ACA), on stroke outcomes in a cohort of patients with LVO and middle cerebral artery (MCA) occlusion, undergoing endovascular thrombectomy (EVT). METHODS: This is a retrospective cohort study performed in a comprehensive tertiary stroke center. The study population consisted of consecutive patients with LVO with proximal MCA occlusion (M1) between June 2016 and April 2021, undergoing EVT. Demographic, clinical, and imaging information was extracted from patient files. Patency and diameters of ipsilateral A1-ACA and PComA were manually measured on admission CT angiography images in the core laboratory. RESULTS: One hundred and five patients with LVO comprised the study cohort, mean age 72.3 years, 43.8% were male, mean National Institutes of Health Stroke Scale score at admission 15.2. The cohort was grouped according to CW vessel characteristics. On univariate analysis, a well-developed PComA was associated with lower rates of hemorrhagic transformation (1.8% vs 14.3%, P=0.01) and a trend towards lower mortality rates (8.9% vs 20.4%, P=0.08).On multivariable regression analysis a well-developed PComA emerged as an independent predictor for survival (aOR=0.09, 95% CI 0.01 to 0.4 for survival at discharge, P=0.009, aOR=0.22, 95% CI 0.05 to 0.8 for survival at 90 days, P=0.02). CONCLUSIONS: In a cohort of patients with LVO due to M1 occlusion undergoing EVT, a well-developed PComA was associated with significantly lower hemorrhagic transformation rates, a trend towards better functional outcomes, and independently predicted survival. Larger studies are needed to understand the differential effect of CW collateral conduits on stroke outcome and evaluate the practicality of incorporating such factors in the clinical decision-making process prior to EVT.
ABSTRACT
Inflammatory Myofibroblastic Tumors (IMTs) are rare fibroblastic/myofibroblastic neoplasms that affect predominately pediatric patients and young adults. Almost half of the patients with IMTs have a chromosomal abnormality in the Anaplastic Lymphoma Kinase 1 gene on chromosome 2p23. Although these tumors occur primarily in the lung, lesions have been reported in a variety of intra-abdominal organs like the liver, spleen, and mesentery. Small bowel IMTs are particularly rare. IMTs generally pursue a benign clinical course, however intra-abdominal and retroperitoneal tumors have typically shown higher local recurrence and even distant metastases. The most common presenting symptoms of an intra-abdominal IMT are abdominal pain and change in bowel habits. Laboratory results are nonspecific and can include anemia and minor elevation of inflammatory markers like C-reactive protein. We report an unusual case of IMT in the small bowel causing the obstruction.
