Ultrasound–Fluoroscopy Versus Ultrasound Guidance for Catheter Drainage of Loculated Pleural Effusions: A Retrospective Study

Background: Loculated pleural effusion—characterized by fibrinous septations that compartmentalize the pleural space and impede drainage—is a technically demanding indication for percutaneous catheter drainage (PCD), in which accurate catheter placement directly determines drainage success. Whether fluoroscopic guidance reduces reintervention compared with ultrasound guidance alone in this population is unknown. Methods: We conducted a retrospective cohort study of 190 PCD procedures for loculated pleural effusion at a single tertiary-care center (Samsung Changwon Hospital, Changwon, South Korea; 118 ultrasound-guided [US alone], median age 71 years; 72 combined ultrasound-and-fluoroscopy-guided [US + Fluoroscopy], median age 75 years). Underlying etiologies included parapneumonic effusion, empyema, malignant effusion, and other causes. The primary outcome was any reintervention. Between-group comparisons used the Mann–Whitney U and Fisher’s exact tests; adjusted analyses included multivariable logistic regression, 1:1 propensity score matching (PSM), and Cox proportional hazards modeling. Results: Reintervention occurred in 35.6% of US alone versus 18.1% of US + Fluoroscopy procedures (relative risk 0.51, 95% CI 0.29–0.88; p = 0.013). After adjustment, US + Fluoroscopy was associated with lower odds of reintervention (adjusted OR 0.42, 95% CI 0.17–0.95; p = 0.043). PSM (60 matched pairs) confirmed this finding (35.0% vs. 16.7%; McNemar’s p = 0.046). The Cox model showed a directionally consistent association (adjusted HR 0.50, 95% CI 0.25–1.02; p = 0.056; log-rank p = 0.012). Conclusions: Combined ultrasound-and-fluoroscopy guidance was associated with a significantly lower reintervention rate than ultrasound guidance alone, with consistent direction of effect across unadjusted and adjusted analyses. These findings support fluoroscopy as an adjunct modality for this technically demanding indication.