Modified thoracoscopic pleural cryo-biopsy in diagnosis of exudative pleural effusion of undetermined etiology

Background Rigid thoracoscopy is the gold standard tool for diagnosing exudative pleural effusion, but sometimes it is difficult to obtain sufficient biopsies using the conventional forceps. This study evaluated the efficacy, safety, and diagnostic value of a modified technique using cryoprobe to obtain pleural biopsies during thoracoscopy. Results This is a single-center prospective study in patients that underwent rigid thoracoscopy using conventional rigid forceps followed by a cryoprobe at the same setting after injection of subpleural mixture of adrenaline and xylocaine. Biopsies were reviewed by an independent pathologist; any complications were recorded, and all patients were followed-up post-procedure. Twenty-four patients (12 males; mean age was 56 +/- 15.1years) were included. The diagnostic yield of both rigid forceps biopsy (RFB) and cryoprobe biopsy (CPB) was 100%. CPB had more surface area than RFB with no difference regarding largest diameter (p = 0.064). RFB and CPB had similar results regarding presence of fat cells. CPB had much less crushed cells than RFB with better tissue preservation (p = 0.004). No significant complications were reported. Conclusions The modified cryoprobe biopsy is a highly effective and safe way for obtaining pleural biopsy besides affording good quality and size of the biopsy especially in thick firmly adherent pleura.