Retina research update

December 3, 2021 Dr Francesc March de Ribot

Characteristics of patients with complete VA recovery after vitrectomy for macula-off retinal detachment
Konstantinidis L et al
Eye (Lond). 2021 Oct;35(10):2834-2839

 

Review: The aim of this retrospective study was to investigate potential factors predicting complete recovery of visual acuity (VA) following surgery for macula-off retinal detachment (RD). Seventy-four patients with complete VA recovery were compared to 83 patients with comparable baseline characteristics but partial VA recovery after vitrectomy for macula-off RD. Of these, 58% of eyes had preoperative VA equivalent of counting fingers or less.

 

The majority of the patients with complete VA recovery (91%) had up to three-day macular detachment (MD) before surgery. In comparison, only 18% of the group of patients with partial VA recovery after vitrectomy for macula-off RD had been operated on within three days of MD. In 63% of the patients with complete VA recovery, OCT images showed a retained foveal depression of the detached retina, whereas only 35% of eyes with partial VA recovery showed a retained foveal depression.

 

The authors concluded that patients had significantly better chances of complete VA recovery when operated on within three days of MD, in comparison to more delayed surgery. Additionally, preservation of the foveal depression of the detached retina appeared to be a common characteristic among patients demonstrating complete visual recovery.

 

Comments: Visual recovery after macula-off RD surgery has been related to preoperative vision and time of evolution. This study indicates that a short duration of RD may play a significant role in determining visual prognosis. Therefore, a timeframe for surgery of macula-off RDs in the first week has been considered good, but earlier intervention is probably still the treatment of choice.

 

 

VA, vitreous haemorrhage and other ocular outcomes after vitrectomy vs aflibercept for vitreous haemorrhage due to DR
Glassman AR et al
JAMA Ophthalmol. 2021 Jul 1;139(7):725-733

 

Review: The aim of this study was to investigate outcomes between vitrectomy with pan-retinal photocoagulation (PRP) vs aflibercept in eyes with vitreous haemorrhage due to proliferative diabetic retinopathy (PDR). Clinical trial randomly assigned patients to four monthly injections of aflibercept vs vitrectomy with PRP, evaluating VA and clearance of vitreous haemorrhage. It included 205 eyes and the median time to clearance of the initial vitreous haemorrhage was 36 weeks in the aflibercept group vs four weeks in the vitrectomy group.

 

The authors concluded that initial aflibercept and vitrectomy with PRP are viable treatment approaches for PDR-related vitreous haemorrhage with the same VA at 24 weeks. However, eyes receiving initial vitrectomy with PRP had faster vision recovery over 24 weeks (when baseline VA was worse than 20/800) and faster vitreous haemorrhage clearance. 

 

Comments: The process of choosing a treatment approach is complex and must be individualised. However, the effect on VA, in the short and long term, is a critical concern. Although VA was not significantly different between groups by 12 weeks and over two years, there was a difference in VA at four weeks, favouring initial vitrectomy with PRP. Therefore, patients who want to hasten their visual recovery may choose vitrectomy, which also minimises clinic visits and injections. One-third of eyes in each group received the alternative treatment per protocol during two years of follow-up. Adherence with long-term follow-up should be stressed because eyes with vitreous haemorrhage from PDR may need supplemental treatment after initial aflibercept or vitrectomy with PRP. These factors may influence treatment decisions for patients initiating therapy for PDR-related vitreous haemorrhage.

 

 

Microcystic macular oedema and cystoid macular oedema before and after epiretinal membrane surgery
Lee DH et al

Retina. 2021 Aug 1;41(8):1652-1659

 

Review: The aim of this retrospective study was to investigate the types of intraretinal cysts (IRCs) associated with epiretinal membranes (ERM) and to evaluate the effects of each type of intraretinal cyst on postoperative outcomes. The study included 100 patients before surgery. Intraretinal cysts were subdivided into cystoid macular oedema with angiographic leakage and microcystic macular oedema (MMO) without angiographic leakage. Intraretinal cysts were present in 54% eyes before surgery, of which 27% eyes had MMO, 18.0% showed cystoid macular oedema and 9% showed cystoid macular oedema and MMO. After surgery, the number of eyes with cystoid macular oedema decreased significantly, whereas the number of eyes with MMO did not. The absence of preoperative MMO, poorer initial visual acuity, increased central foveal thickness (CFT) and intact ellipsoidal zone were associated with favourable visual recovery.

 

The authors concluded that MMO associated with epiretinal membranes was a poor prognostic factor for epiretinal membrane surgery. The persistence of MMO after surgery affirms related chronic structural changes. Further studies should investigate whether earlier surgical intervention could benefit visual outcomes before the development of MMO.

 

Comments: Vitrectomy for treatment of ERM results in significant improvement in vision, CFT and IRCs. The relationship between ERMs and macular oedema has long been established; the incidence rate of CME after cataract surgery, in another study, was 8.6% in patients with ERMs, whereas the rate was 1.38% for patients without ERMs. Macular oedema and IRCs are frequently associated with ERMs and they may disappear, persist or develop after ERM surgery. Chronic structural changes associated with ERMs may affect retinal function, which can hinder the recovery of the retina after surgical removal of ERM. The presence of MMO is associated with poor visual outcomes after surgery, suggesting that ERM surgery should be performed before significant structural damage occurs. 

 

 

Dr Francesc March de Ribot is a consultant ophthalmologist specialising in retinal diseases and vitreoretinal surgery, with a particular interest in clinical research. He’s based at Dunedin Hospital SDHB and is collaborating with ADHB in Auckland.