[The St. Gallen digital ophthalmological imaging system].

BACKGROUND: Digital photography has many advantages over the conventional method. At present commercially available digital ophthalmological imaging systems utilise only a fraction of the advantages of this technique and some of them have fundamental conceptional problems.

METHODS: Images of a fundus camera, a slit lamp and a scanning laser ophthalmoscope were digitised using digital and video cameras and/or frame grabber cards. Digital images and movies were recorded via a personal computer. The image recording software was developed using an imaging library and open source software. The recorded images and video sequences were processed with three different commercially available programme packages. The images were archived in a around-the-clock accessible database.

RESULT: Our digital imaging system is capable to record normal and high resolution slit lamp images, colour fundus images in normal resolution, Fluorescein angiography images in normal and high resolution, digital simultaneous ICG and Fluorescein videoangiograms (without compression) and high resolution macro images. Different functions, e.g., contrast enhancement are integrated in the image capture software. Most of the parameters of the image acquisition are individually adaptable. The digital image archive supports multiple image and video formats.

CONCLUSIONS: Using standard software and hardware components an imaging system can be constructed featuring functions usually not available in commercial ones. Since the system is adaptable, recording of images with a wide variety of parameters, e.g., for measurements for scientific experiments, is possible.