Surgical cystotomy for refractory diabetic cystoid macular edema

Dear editor

I read with interest the article on cystotomy for refractory diabetic cystoid macular edema (CME) by Asahina et al.¹ Intraoperative optical coherence tomography (OCT) (RESCAN 700; Carl Zeiss Meditec AG, Jena, Germany) is a new interesting addition to ophthalmic surgeons’ armamentarium.² Few aspects regarding the manuscript¹ need further discussion. 1) The exact definition of “refractory CME” needs elaboration. 2) The positive effect on visual recovery after surgery may also have been influenced by the simultaneous cataract surgery in some cases. It would be interesting to compare the visual gain of patients with cystotomy only versus cystotomy with cataract surgery. 3) A 41-gauge subretinal injection needle (DORC International, Zuidland, the Netherlands)³ may also be used for cystotomy. It has the theoretical potential of reduced surgical trauma compared to a 27-gauge needle, and may also be used to flush the intraretinal fluid in such cases. 4) The exact role of intraoperative OCT will be more substantiated if the authors could provide a surgical video or figures showing the use of intraoperative OCT. 5) Puncture of the cystoid spaces at the macula is an innovative surgical technique.^1,4 However, in the 1999 paper by Tachi et al,⁴ the visual acuity remained same or worsened after surgery in 17 of 22 eyes. CME puncture for long-standing refractory CME resulted in resolution of CME without a significant improvement in visual acuity in the study by Singh et al.⁵ In the study by Asahina et al,¹ 18 of 20 eyes had maintained or improved visual acuity after surgery. Thus, cystotomy adds to the limited treatment options for resistant diabetic CME.

Disclosure

The author reports no conflicts of interest in this communication.