NEGATIVE EFFECTS OF VITAL DYES AFTER UNEVENTFUL VITREOMACULAR SURGERYRöhrig, Stephan MD*; Farecki, Marie-Louise MD†; Boden, Karl T. MD*; Haus, Arno MD*; Gutfleisch, Matthias MD†; Jung, Sascha PhD; Lommatzsch, Albrecht MD†; Szurman, Peter MD*; Januschowski, Kai MD*RETINA: September 2019 - Volume 39 - Issue 9 - p 1772–1778 doi: 10.1097/IAE.0000000000002231 Original Study Buy Abstract In Brief Author InformationAuthors Article MetricsMetrics Purpose: Vital dyes have become a clinical standard during chromovitrectomy but toxicity remains an issue. We compared the clinical outcome of one supposedly toxic vital dye (AV 17 with 5% mannitol) with a standard vital dye (MBB Dual) and performed a power analysis for future comparative studies. Methods: Retrospective analysis of 270 eyes after chromovitrectomy with internal limiting membrane peeling because of macular holes. Primary endpoint was loss in BCVA >2 lines and photoreceptor atrophy as seen on optical coherence tomography examination. Results: In 173 eyes, staining of the epiretinal membrane and extracellular matrix was performed using MBB (Group A), and in 97 using AV 17-M (Group B). The mean BCVA was not significantly different after more than 3 months and also not in the early postoperative period after surgery between Group A and Group B. The number of patients suffering from a decline in BCVA of two lines and more was not significantly higher in patients of Group B. There was not a significantly higher percentage of patients with an inner segment/outer segment defect. Conclusion: Our rather homogeneous study showed no significant difference between both dyes. Thousand five hundred patients would need to be examined to find a significant difference in future studies. The aim of this retrospective study was to investigate negative effects of two vital dyes (AV 17 with 5% mannitol and MBB Dual) after surgery. Because of the results, it is advisable to perform postmarketing analysis to increase patient safety. *Eye Hospital Sulzbach, Sulzbach/Saar, Germany; and †St Franziskus Eye Hospital Münster, Münster, Germany. Reprint requests: Stephan Röhrig, MD, Eye Clinic Sulzbach/Saar, An der Klinik 10, Sulzbach 66111, Saar, Germany; e-mail: email@example.com None of the authors has any financial/conflicting interests to disclose. © 2019 by Ophthalmic Communications Society, Inc.