In pulmonary embolism, findings in perfusion scan isa) Perfusion segmental defectb) Perfusion defect with normal lung scan & radiographyc) Tenting of diaphragmd) Normal chest scan: (A) abd, (B) bcd, (C) abc, (D) ab
Answer is A. At least 2% of patients with PE have normal V/Q scan and 4% of patients with normal V/Q scan have pulmonary embolism.
41% of patients with PE have high probability scan which includes 2 or more segmental perfusion defects with normal chest radiograph and normal lung ventilation scan.