[Can Postoperative Accelerated Lens Opacification be Limited by Lying in "Face-Down Position" after Vitrectomy with Gas as Tamponade?].

Background: Developing a post-operative cataract after pars-plana vitrectomy (ppV) or core pars-plana vitrectomy (cppV) with gas as tamponade within 6 to 12 months is a common complication and is mostly accepted as unavoidable. Often a combined cataract-ppV surgery in the first place is recommended. The main goal of this study was to analyse the effects of a "face-down positioning" ("fdp") on the lens transparency and the phaco rate. By using the positive experience of an ergonomic body positioning it should be possible to improve the compliance during the period of "fdp" after surgery.

Methods: During the study period of up to 24 months, we observed in a prospective, controlled, clinical and randomised pilot study 30 patients who all had undergone a ppV/cppV with sulfur hexafluoride gas tamponade (SF6 25 %). All patients of the supported group (SG) and the control group (CG) were requested to keep their face consequently downwards until the gas bubble was resorbed completely in order to avoid a direct contact with the lens. The real time in "fdp" in hours per day (24 hours) and the grade of lens opacification was documented pre- and postoperatively using a Pentacam HR (Oculus, Wetzlar).

Results: The compliance of patients tested measuring the real time of "fdp" in hours per day varied largely (SG: 19.5/24; CG: 5.5/24; p < 0,0001). Cataract development was found to be directly related to the real time of "fdp". A cataract surgery was necessary mainly in the non-supported group (SG: 4/15; CG:12/15; p = 0.012). There was no lens opacification in the supported group after performing the "fdp" for at least 20 hours daily until the resorption of the gas bubble was completed. This result did not correlate with the age of the patient.

Conclusion: With the help of sufficient support at the disposal of the patients, it is possible to significantly improve the compliance during the period of "fdp" after surgery. In order to get a safe and painless "fdp" in bed, an ergonomic body positioning is necessary (Schaefer 2012). By practicing the "fdp" until the gas bubble is completely resorbed, the risk of developing a postoperative cataract can be reduced significantly. Provided there is a good compliance to "fdp", the gas bubble can cause the desired tamponade effect even when using shorter acting gases. By performing a consistent "fdp" it is possible to accelerate the healing process and avoid reoperations. Hereby it should even be possible to use an SF6-air mix or optionally simply air as tamponade.