Efficacy And Safety Of Thoracoscopic Cryobiopsy In Patients With Undiagnosed Exudative Pleural Effusion

Inclusion Criteria: * patients diagnosed as exudative pleural effusion according to Light criteria .informed written consents were taken from all patients enrolled in the study Exclusion Criteria: * patients who refused participation ,patients unfit for medical thoracoscopy (MT) will be excluded from the study such as:Uncooperative patient ,Severe uncorrected hypoxemia in spite of continuous oxygen administration, because it's necessary to keep oxygen saturation above 90 % during procedure ,patients who could not tolerate the lateral decubitus position for a period long adequate to do the thoracoscopy, unstable cardiovascular or hemodynamic condition, uncorrected Coagulation defects and small pleural space