TITLE:- To Study the effect of Cranioplasty on cerebral blood flow with clinical outcome in a patient who underwent decompressive craniectomy Aims: This study was done to evaluate the effect of cranioplasty on CBF with computed tomography perfusion (CTP). It also aimed to determine the correlation between postcranioplasty CBF and clinical outcome. Settings and Design: Prospective observational study. Subjects and Methods: All patients had CTP done to determine precranioplasty CBF. CTP was repeated at 6 weeks postcranioplasty and clinical assessment at 6 and 24 weeks postcranioplasty. Results: The median value of ipsilateral CBF was 52. 9and 64.10 ml/min/100 g at precranioplasty and postcranioplasty.contralateral CBF also showed improvement from 67.4 to 74. 7 ml/min/100 g at precranioplasty and postcranioplasty.contralateral. Median value for mini mental state examination showed a significant difference with value of 22, 25, and 25.5 at precranioplasty, 6 and 24 weeks postcranioplasty (P = 0.001 and P < 0.001). Median value for frontal assessment battery was 12, 14.5, and 15 (P = 0.002 and P = 0.001). Conclusions: Cranioplasty can improve cortical perfusion for both ipsilateral and contralateral hemisphere. Cranioplasty was observed to have a therapeutic role in terms of clinical outcome improvement.ce