The Diagnostic Dilemma of Pulmonary Embolism: Is It a Clinico-Investigatory Portrayal or Only an Investigatory Portrayal? A Clinically Based Study

Abstract

Objectives: A balanced comparison between single photon emission computed tomographic (SPECT) lung scintigraphy with the planar imaging and multislice (MS) spiral computed tomography (CT) and correlating the outcomes with the clinical probabilities. Background: Pulmonary embolism (PE) is a potentially lethal serious problem with a confusing clinical database to diagnose. In the majority of the studies, the clinical probabilities were always in the scope of the secondary consideration, although they are the gates, patients step through to the investigatory zone. Methods: 68 patients suspected for PE (66% females and 34% males, mean age 43.5±15.3) were evaluated for pretest clinical probability score (PCPS) and investigated with ventilation/perfusion lung scintigraphy (planner & SPECT) and MS spiral CT. Results: 63% and 45.5% were positive for dyspnoea and deep venous thrombosis, respectively. They have low, intermediate and high PCPS of 47.1, 17.6 and 35.3%, respectively. Planner and SPECT studies were positive in 28/68 and 33/68 cases, respectively. SPECT showed 25 % more positives in the high clinical probability group (p-value 0.02). MS spiral CT was positive in 9/25 and negative in 16/25, with 2/25 false positive with SPECT and 4/25 disagreement with planner scans. Sensitivity, specificity, positive and negative predictive values were (100%, 87.5%, 81.8% and 100%) and (77.8%, 87.5%, 77.8% and 87.5%) for planner and SPECT, respectively. Conclusion: SPECT scintigraphy potentiates the diagnostic power of the clinical probability of the suspected cases with PE. It detects more positives and changes the planner based PIOPED categories, so we advise its routine use.