Analyse der primären Pars-plana Vitrektomie ohne eindellende Chirurgie in der Behandlung von rhegmatogenen Netzhautablösungen

There are two existing treating methods for rhegmatogenous retinal detachment, scleral buckling surgery and primary pars plana vitrectomy. Over the past years vitrectomy gained an expanding role as the procedure of choice in treating rhegmatogenous retinal detachment. To define the optimal method for treating retinal detachment, it is important to discuss advantages, complications and limitations of each technique. Our purpose was to examine primary pars plana vitrectomy treatment without additional scleral buckling for rhegmatogenous retinal detachment. Main outcome measures were anatomic success rates, visual acuity and complications. Optical coherence tomography was used to investigate ultrastructual changes after vitreoretinal surgery of the macula. The medical records of 626 consecutive patients with rhegmatogenous retinal detachment were reviewed. 229 eyes were treated by primary pars plana vitrectomy and 117 eyes were treated without additional scleral buckling. Most of these 117 eyes had complicated retinal detachment including giant retinal tears, dense vitreous opacities, retinal detachment with multiple breaks and proliferative vitreoretinopathy. The study group consisted of 89 eyes, which had a minimal follow-up of 6 months regarding the defined endpoints. Optical coherence tomography could be performed in 42 eyes. Primary pars plana vitrectomy yielded a reattachment rate of 86.5%. Redetachment occurred from 2 weeks to 4 months postoperatively and two of three redetachments were associated with new reatinal breaks. Proliferative vitreoretinopathy was another reason for redetachment. The second-procedure success rate was 98.8%. Only one eye with long existing proliferative vitreoretinopathy stadium c and beginning phtisis bulbi ended in phtisis. Functional outcome is most important for the patient. In the end (of follow-up) all patients with macula-off detachment had improved their visual acuity. 7.3% with macula-on detachment suffered a deterioration of visual acuity in the end. In all these cases redetachment was the cause of loss of visual acuity. This underlines the importance of primary anatomic success. Postoperative visual recovery reached nearly the maximal endpoint after 3 months, although visual acuity continued to improve slightly up to 24 months postoperatively. After previous retinal detachment repair by primary pars plana vitrectomy 90% of preoperatively phakic eyes developed secondary cataract. At the time of primary pas plana vitrectomy all patients with postoperative cataract formation were older than 50 years. Combined pars plana vitrectomy, phacoemulsification and intraocular lens implantation could successfully restore vision in these patients. Epiretinal membranes were another frequent complication after primary pars plana vitrectomy (9%). Other complications included secondary glaucoma (4.5%), macula hole (1.1%), macula oedema (1,1%), perfluorocarbon retention (2.2%), posterior synechiae (2.2%) and diplopia (1.1%). In all patients periphery vitrectomy including extended vitreous base cleaning with scleral indentation and examination was performed. The single-procedure success rate for the treatment of complicated retinal detachment in this case series was very high. Postoperative proliferative vitreoretinopahty also occurred rarely. So there is good reason to doubt, that additional cerclage would yield higher single-procedure success rate. Additional cerclage may be indicated in cases of additional pathology at vitreous base. Postoperativ assessed optical coherence tomography showed normal microanatomy with presence of foveal depression and absence of cystoid macula edema in 64%. Absence of morphological changes of the macula after retinal detachment can not predict normal visual acuitiy. Most frequent structural change was an epiretinal membrane (19%). Almost every epiretinal membrane was found in eyes with macula-off detachment. The trigger for the formation of epiretinal mambranes in eyes with macula-off detachment remains unclear. Retinal thickness analysis of the morphological intact eyes yielded a higher maculavolume compared to the healthy partnereye independent from preoperative macula-status. This trend was very clear, but could not reach statistic signifance due to a small collective. Although these results indicate that there is cellular remodelling after retinal detachment independent of macula-status, this type of study can make no statement to the pathophysiological mechanisms.