Diagnostic Efficacy of Ventilation-Perfusion Single Photo Emission Computed Tomography/Computed Tomography for Pulmonary Hypertension due to Fibrinous Mediastinitis

Acad Radiol. 2024 Dec 18:S1076-6332(24)00872-9. doi: 10.1016/j.acra.2024.11.026. Online ahead of print.

Abstract

Rationale and objectives: Comprehensive data on the use of ventilation-perfusion single-photo emission computed tomography/computed tomography (V/Q SPECT/CT), an established diagnostic tool for chronic thromboembolic pulmonary hypertension, in identifying pulmonary hypertension secondary to fibrinous mediastinitis (PH-FM) is scarce. This study aimed to assess its diagnostic efficacy for PH-FM.

Materials and methods: Patients with PH due to pulmonary artery stenosis were assessed using V/Q SPECT/CT, computed tomography pulmonary angiography (CTPA), and digital subtraction pulmonary angiography (PAG). Abnormal mediastinal or hilar features identified by V/Q SPECT/CT, correlating with perfusion defects, were used to diagnose PH-FM. Final clinical diagnosis is recognized as the gold standard for this study. Diagnostic accuracy was compared using receiver operating characteristic (ROC) analysis and Cohen's kappa coefficient to evaluate agreement among the imaging methods.

Results: Among the patients included, 21 had PH-FM, and 76 had PH associated with non-FM. V/Q SPECT/CT showed higher sensitivity (90%), specificity (95%), and accuracy (94%) for detecting PH-FM compared to CTPA (sensitivity 86%, specificity 92%, accuracy 91%) and PAG (sensitivity 62%, specificity 87%, accuracy 81%). The areas under the ROC curve for V/Q SPECT/CT, CTPA, and PAG were 0.93, 0.89, and 0.74, respectively. V/Q SPECT/CT achieved better agreement with the gold standard than CTPA or PAG (κ=0.82, κ=0.69 and κ=0.49, respectively).

Conclusion: V/Q SPECT/CT demonstrates superior diagnostic efficacy and accuracy compared to CTPA and PAG in diagnosing PH-FM.

Clinical relevance statement: Compared to computed tomography pulmonary angiography and digital subtraction pulmonary angiography, ventilation-perfusion single-photo emission computed tomography/computed tomography demonstrates superior diagnostic efficiency for pulmonary hypertension secondary to fibrinous mediastinitis, leading to improved early detection and accuracy, thus optimizing diagnostic pathways.

Keywords: Diagnostic accuracy; Fibrosing mediastinitis; Pulmonary hypertension; Ventilation-perfusion single-photo emission computed tomography/computed tomography.