OBJECTIVE: The statement that @entity1653 are @entity5 has to be seriously questioned from a surgical standpoint. The purpose of this study was 1) to analyze the operative reports of a personal series of @entity1653 to evaluate the percentages of the @entity5 that could be dissected by passing in the extrapial plane (i.e., "cleavable") and of those in which the dissection had to be subpial (i.e., "noncleavable") and 2) to see whether preoperative angiography could help in predicting cleavability. METHODS: The series includes 150 consecutive @entity1 with @entity1653 diagnosed with computed tomographic scans and explored preoperatively by selective external/internal carotid angiography, operated on using microsurgical techniques, and followed for more than 4 years. RESULTS: Dissection between @entity5 and underlying cortex could be achieved in the extrapial plane predominantly (i.e., on more than two-thirds of the interface) in only 54.6% of @entity1 . On angiography, the pial-cortical arterial supply participated in at least equal part with the meningeal-dural arterial supply in vascularization of the @entity5 in 59.4% of @entity1 . In this group, dissection could pass through the extrapial plane in only 34.8% of @entity1 . Conversely, when meningeal-dural arterial supply was predominant on angiography, which occurred in 40.6% of @entity1 , dissection could be achieved in the extrapial plane in 83.6% of @entity1 . This difference is statistically significant (P < 0.001). CONCLUSION: Participation of pia mater in the vascular supply of @entity1653 , and consequently, difficulty of dissection, can be predicted preoperatively on angiography. Knowledge of the arterial supply of the @entity5 before surgery is an important aid to the surgeon in preparing for and performing the operation.

Most XXXX are not @entity5 : anatomic-surgical evidence and angiographic predictibility.

@entity5 :: ('MESH:D009369', 'Disease') :: ['tumor', 'cleavable tumors', 'tumors'] @entity1 :: ('9606', 'Species') :: ['patients'] @entity1653 :: ('MESH:D008579', 'Disease') :: ['intracranial meningiomas', 'meningiomas']
@entity1653 :: (MESH:D008579,Disease) :: ['intracranial meningiomas']
