RESUMO
PURPOSE: To investigate the feasibility of performing vitrectomies while viewing a three-dimensional image on a large display in a heads-up position. METHODS: Twenty volunteers were compared performing meticulous tasks using the heads-up and the traditional method. Some optical parameters, resolution and depth of field, were measured, and the possibilities of digital image processing were investigated. In addition, routine use of the heads-up method for >400 vitrectomies over 8 months was retrospectively analyzed. RESULTS: Of note, 91.7% of the volunteers preferred the ergonomics of the heads-up technique. The two methods were judged to be similar regarding speed and ease of microscopic manipulations and sharpness of image. Significantly fewer mistakes were made with the heads-up method. The measured resolution of the eyepieces was approximately twice that of the three-dimensional display, whereas depth of the field was about equal. Electronic amplification of the camera's signal resulted in increased image brightness, allowing use of reduced endoillumination levels. In clinical routine, better ergonomics, digital image processing, and use of a large display are found to be major advantages. CONCLUSION: The heads-up method is well suited for vitreoretinal surgery. With further technical improvements, the procedure should soon find widespread use.