Sparing of the hippocampus indicates better collateral blood flow in XXXX .

@entity1 @entity4798 @entity2806 @entity1188 @entity432
BACKGROUND: In acute posterior cerebral artery, occlusion involvement of the hippocampus is a common finding. Nevertheless, until today, @entity1188 and @entity2806 evolution in the hippocampus has not been studied systematically. AIM: Evaluation of @entity4798 patterns in @entity432 in the very early phase ( <=six-hours) and @entity2806 evolution on follow-up magnetic resonance imaging in relation to collateral blood flow assessed by a magnetic resonance imaging-based approach was conducted. METHODS: In 28 @entity1 [mean age 69  4        13  8 years, 19 (67  9%) males, 10 (32  1%) females] with proximal @entity432 , magnetic resonance imaging findings were analyzed, with emphasis on @entity4798 patterns on diffusion-weighted images and collateralization on dynamic 4D angiograms derived from perfusion-weighted raw images. RESULTS: On initial diffusion-weighted images, we identified all known @entity4798 patterns: type 1 (complete) in 6/18 (33  3%) @entity1 , type 2 (lateral) in 10/18 (55  6%) @entity1 , and type 3 (dorsal) and type 4 (circumscribed) in 1/18 (5  6%) @entity1 respectively. On dynamic 4D angiograms, the grade of collateralization was classified as 1 in 9 (32  1%), 2 in 1 (3  6%), 3 in 10 (35  7%), and 4 in 8 (28  6%) @entity1 . On follow-up diffusion-weighted images, we found new @entity2806 in three and @entity1188 growth in the hippocampus in five @entity1 . @entity1 with better collateralization (grades 3 and 4) less often had hippocampal @entity1188 on initial (P   =   0  003)/follow-up diffusion-weighted images (P   =   0  046) as well as type 1 on initial (P   =   0  007)/follow-up diffusion-weighted images (P   =   0  005). CONCLUSIONS: Involvement of the hippocampus in proximal @entity432 is frequently but not obligatorily observed and highly dependent on the extent of collateralization. The same holds true for @entity4798 patterns.
