Endoscopic Vitrectomy: A new Surgery Technique

H.L.J. Knorr, A. Jünemann

Abstract

Backround: Opacity of optical media as well as inkomplete imaging of the region from the pupillary rim to the ora serrata, restrict the conventional pars plana vitrectomy. Aim of this presentation is the introduction of a new endoscopic vitrectomy method.

Material and Methods: The endoscope ( VITROPTIC ) is a fiberoptical instrument with 6000 pixel and integrated lighting that guarantees illumination to a depth to 15mm, which is built into a canula with an outside diameter of 0.9mm. Within this canula is an additional irrigation channel for continuing irrigation or infusion . The endoscope is supplied with a Fix-Focus eyepiece in a standard eyepiece-funnel (diameter 32mm) attached to a TV-Adapter, having a focal distance of 35mm. The TV-adapter is connected to the miniature camera head of a special camera ( ENDOGNOST ) by a C-mount and is held by a 3-joint-arm. The horizontal resolution of the camera is 460 lines (PAL). A CCD-sensor, consisting of 440.000 pictures elements with a complementary. produces, after white balance has been adjusted automatically, an endoscopic picture with excellent colour reproduction. If light intensity is to high (total reflection), the electronic shutter can increase shutter speed up to 1/2.000.000 sec. Using a light cable, a 1.000 XENON light source (100W, colour temperature 5.800° Kelvin, with integrated UV/IR-Filter) is connected to the endoscope. Endoscope pictures can be produced on all commercial monitors and video-systems. The endoscope can bee completely immersed in standard desinfactant solutions and also be gas- and plasmasterilized.

Results: Whereas previously partially visible regions, such as iris posterior surface, iris root, ciliary body and vitreous base could be only observed by mechanical indenting of the bulbus, the new instrument enables complete observation during removal of vitreous base, membrane peeling of anterior-loop-traction-situations, pseudophacic retinal detachements and indirect cilary body surgery (i.e. tumors, epithelial invasion). This new intrument allows high magnification of minimal changes in the macular area. Alterating between transpupillar and endoscopic sight facilities orientation on a three dimensional basis.

Conclusion: The described endoscopic vitrectomy enlargens the range of possibilites of conventional pp-vitrectomy, especially by revealing "dead angles" of the eye or opacities of optical media.

Dr. Knorr and Dr. Jünemann have no direct financial interest in the products mentioned in this abstract or they are no paid consultant for any companies mentioned.

VITROPTIC is an registrated trademark of POLYDIAGNOST GmbH, D-85293 Reichertshausen, Germany.