_BACKGROUND:_Although the main pathological changes have been defined in the pulmonary vascular bed in Chronic Obstructive Pulmonary Disease (COPD), we postulated that the retrobulbar hemodynamics might also be changed in those patients. _AIM OF THE WORK_:_AIM OF THE WORK_: to evaluate the retrobulbar arterial blood flow changes in COPD patients by color Doppler ultrasonography._Methods:_ Fifteen stage I COPD, 16 stage ... Read more