Dear Editor,

We congratulate the authors Ghazi-Nouri et al. to their recently published study “Visual function and quality of life following vitrectomy and epiretinal peel surgery”. It mainly confirms our results on a very similar consecutive cohort of 20 patients followed for three months which was published August 2005 in the Medline indexed German “Ophthalmologe” [1] and therefore represents the first paper on this subject. The first oral presentation was at the 2004 annual meeting of the German Ophthalmological Society (DOG).

For assessing the benefit in visual quality of life after vitreoretinal surgery for epiretinal membranes, we used the commonly accepted Visual Function 14 (VF-14) test. A larger patient series using the NEI-VFQ 25 is ongoing. Similarly as in the recent study of Ghazi-Nouri et al., a significant increase in visual quality of life 3 months after surgery was observed. The VF-14 values increased significantly from 72.8 preoperatively to 83.3 postoperatively (p<0.05) - although the fellow eye had good visual acuity (visual acuity of –logMAR 0.2 or better was an inclusion criteria), so that every patient underwent surgery on the worse seeing eye. In contrast to Ghazi-Nouri et al., visual acuity increased significantly from –logMAR 0.55 to 0.4 (p=0.018), which is approximately 1.5 Snellen lines and consistent with most previously reported results in the literature (2, 3). However, all surgery had been performed by only one experienced surgeon.

We performed statistic analyses on the data in order to isolate predictive factors for surgery. When splitting our 20 patients in the two halves with lowest and highest preoperative VF-14 values, it could be shown that patients with preoperatively low VF-14 values benefited from surgery in visual quality of life, while those with preoperatively high VF -14 values did not. In an analysis of variance model it could be further shown, that the increase in visual quality of life could better be estimated than the increase of visual acuity. If in such modelling only the preoperative VF-14 values and preoperative visual acuity were used to assess the increase in visual quality of life, those two parameters had a surprisingly high predictive value (R2=0.80). Cataract surgery did not influence results significantly. Thus in addition to the later published results of Ghazi-Nouri et al., we can give practical recommendations for patient selection: a patient with preoperatively low VF-14 values (i.e. the patient is highly bothered by the visual performance) and a preoperatively low visual acuity is very likely to benefit from surgery. Together with the information that the increase in visual acuity will probably be not very high, this allows for best consulting and patient selection for epiretinal membrane surgery.

C. Hirneiss, MD
A.S. Neubauer, MD
A. Kampik, MD

Dept. of Ophthalmology
Ludwig-Maximilians University
Mathildenstr. 8
80336 Muenchen
Germany

References

1. Hirneiss C, Rombold F, Kampik A, Neubauer AS. Visual quality of life after vitreoretinal surgery for epiretinal membranes. Ophthalmologe 2005 Aug 3 [Epub ahead of print]

2. Michels RG. Vitrektomy for macular pucker. Ophthalmology 1984;91:1384-1388

3. Haritoglou C, Eibl K, Schaumberger M et al. Functional outcome after trypan blue-assisted vitrectomy for macular pucker: a prospective, randomized, comparative trial. Am J Ophthalmol 2004;138:1-5