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Nodular reverse halo sign in active pulmonary tuberculosis: A rare CT feature?
K Martini1, A Loubet2, A Bankier3
1Department of Radiology, Cochin Hospital, 75014 Paris, France; Diagnostic and Interventional Radiology, University Hospital Zurich, 8091 Zürich, Switzerland.
Purpose:
The purpose of this study was to investigate the prevalence of the nodular reverse halo sign (NRHS) in chest computed tomography (CT) in patients with active pulmonary tuberculosis.
Materials And Methods:
From March 2018 to March 2019, 29 consecutive patients with a culture-confirmed active pulmonary tuberculosis and who underwent chest CT examination during hospital-admission were retrospectively included in the study. There were 24 men and 5 women with a mean age of 40.9±16.7 (SD) years (range: 18-80years). Chest CT examinations of included patients were evaluated for the presence of NRHS and other tuberculosis-related CT signs.
Results:
CT revealed the NRHS in 5 patients (5/29; 17%). The other CT signs of tuberculosis included consolidations in 18 patients (18/29; 62%), tree-in-bud pattern in 14 patients (14/29; 48%), cavitation in 12 patients (12/29; 41%), sparse nodules in 10 patients (10/29; 34%), and pleural effusion in 8 patients (8/29; 28%).
Conclusion:
CT shows NRHS in 17% of patients with active pulmonary tuberculosis, indicating that the sign is not as rare as previously thought in patients with this condition.
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