Medical Thoracoscopy in Pleural Effusion Versus Dry Space: A Narrative Review on Diagnostic Yield and Complication Rates

Background: Medical thoracoscopy (MT) represents the gold standard for undiagnosed pleural effusions, traditionally performed in the presence of pleural fluid. Recent technical advances have enabled MT in “dry space” conditions (minimal or absent pleural effusion), raising questions about comparative diagnostic efficacy and safety profiles. Objective: This literature review aims to evaluate diagnostic yield and complication rates between traditional MT performed in patients with current pleural effusion and dry medical thoracoscopy (DMT). Results: MT demonstrates diagnostic sensitivity ranging from 80% to 96.3% and specificity close to 100% for malignant pleural disease, and the diagnostic accuracy is 99.1% for tuberculous pleuritis. DMT’s recent studies report optimal success rates in pleural access and tissue sampling, and diagnostic sensitivity for malignancy up to 100%, although a confirmation with larger cohorts for technique comparison is needed. Major complication rates are comparable between MT and DMT, with no significant differences in overall adverse events. Mortality rates remain exceptionally low (≤0.1%) for both approaches. Conclusions: MT remains a highly effective diagnostic tool for pleural diseases. DMT represents a valid and safe alternative in patients without significant pleural effusion, although technically more demanding, and further studies are required to validate the technique.