Vitrectomy
The vitrectomy ( Latin vitreus "glass", Greek ek "out" and tomein "cut") is the partial step of an eye operation in which specific parts of the vitreous are surgically removed. If the operation only aims at the vitrectomy, the whole operation is usually named that way.
Indications
Vitrectomy is often required as part of advanced proliferative diabetic retinopathy , with retinal detachment or significant vitreous hemorrhage. It can also be performed as a diagnostic vitrectomy for vitreous opacities of unknown origin. The vitreous body samples are then examined bacteriologically , virologically and cytologically . Retinal detachments with retinal holes are increasingly being treated as part of a vitrectomy and are the most common indication for vitrectomy. Vitrectomy must also be performed to remove epiretinal glioses . In addition, vitrectomy has greatly improved the prognosis of eye injuries with perforation of the dermis , as this procedure also removes foreign bodies that have entered the eye and antibiotics can be applied.
Pars plana vitrectomy
The pars plana vitrectomy (PpV or PPV) is a vitrectomy in a closed system . The vitreous body is accessed through the wall of the eyeball at the level of the pars plana region , a section that lies between the outer edge of the retina and the ciliary body and contains neither large vessels nor functionally irreplaceable tissue.
During the operation, the following tools are introduced through three cuts a few millimeters wide:
- an infusion including suction,
- a light source,
- a surgical tool (vitrectome, special scissors, grippers, hooks).
This allows the vitreous and other tissues involved in the disease to be removed. The infusion maintains the pressure in the eye . In order to cover a detached retina, the vitreous space can be filled with gas , silicone oil or perfluorocarbons . A retina that has been brought into contact again can then be connected to the choroid by means of laser coagulation and / or cold coagulation (freezing). As a result of the sterile inflammatory stimulus of the laser heat or the cold, stabilizing scars are formed, which counteract a renewed detachment of the retina .
Results and Complications
The operation can achieve very good results, but operative and post-operative problems are not uncommon that are now considered manageable. So it is almost always within one to two years after a vitrectomy for forming a cataract (cataract). Other possible complications include a. Retinal detachments, which is why a vitrectomy is only used in exceptional cases for more harmless complaints such as floaters . In the case of diabetic retinopathy and other diseases of the retina, the damage caused by the disease can in part be irreparable, so that, despite a successful vitrectomy, complete restoration of vision is uncertain.
History of the surgical technique
Surgical interventions on the vitreous were avoided until the 1960s because the various complications of vitreous replacement were not yet well mastered. At the time, the common technique was a swab vitrectomy , in which the herniated vitreous tissue is sucked in with a swab, pulled out of the eyeball, and cut off with scissors. The development of special vitrectomes (suction and cutting devices) later made the exertion of tension on the vitreous body unnecessary; this reduced the complication rate considerably.
With the development of vitrectomy in a closed system ( pars plana vitrectomy , PPV), through which a pressure drop in the eyeball can largely be avoided during the operation, the transition from defensive reactions to situations that make an intervention on the vitreous body inevitable to planned use of vitrectomy for a growing number of indications.
The German-born American Robert Machemer (1933–2009) is considered a pioneer in the development of vitrectomy .
