25 Gauge Diabetic Vitrectomy Outcomes with and Without 29 Gauge Twin Light Chandelier Endoillumination


ABSTRACT

Purpose:

To compare anatomical and visual outcomes of 25G vitreo-retinal surgery for diabetic tractional retinal detachments with and without 29G twin light chandelier endoillumination.

Setting / Venue:

Dr. Rajendra Prasad Centre for Ophthalmic Sciences, All India Institute of Medical Sciences, New Delhi

Methods:

It was a prospective, comparative, randomized, interventional clinical study comprising of 46 eyes with diabetic tractional retinal detachment undergoing standard 3 port 25G pars plana vitrectomy using the CONSTELLATION® Vision System (Alcon, Fort Worth, TX, USA). Using a computer generated randomization table, they were divided into two groups (n=23), Group 1: with chandelier and Group 2: without chandelier. The endoillumination used in Group 1 was SynergeticsTM 29G twin light chandelier. Patients with severe media opacity or previous history of vitrectomy were excluded from the study. All eyes received anti-VEGF (Vascular Endothelial Growth Factor) 24 hours before the surgery. Both the groups were comparable in mean age, gender, duration of Diabetes Mellitus (DM), type of DM, mean best corrected visual acuity, mean intraocular pressure & prior PRP (Pan Retinal Photocoagulation) status. Tractional Retinal Detachment (TRD) was divided into TRD involving macula and TRD threatening ma cula as defined by Diabetic Retinopathy Vitrectomy study. The intraoperative parameters noted were a) Duration of surgery (minutes) between the insertion of first port and removal of last port b) Intraoperative complications-significant hemorrhage and/or retinal breaks. The patients were followed up on postoperative day 1, 7, 30, 3 months and 6 months. Appropriate statistical tests were applied and results were considered statistically significant when ‘p’ value was <0.05.

Results:

The mean duration of surgery in group1: 59.61+11.01 minutes and in group2: 70+13.23 minutes, p value=0.006. The intra operative complications were found to be comparable between the two groups, p value=0.765. Silicone oil was injected in 31[Group 1-19(82.61%) and Group 2- 12(52.17%)]; C3F8 in 3[Group 1-none and Group 2-3(13.04%)]; air was injected in 12[Group 1-4(17.39%) and Group 2-8 (34.78%)], p value=0.052. The BCVA improved from mean LogMAR of 1.88±0.12 (Snellen’s equivalent- finger counting at half meter) to a mean LogMAR of 1.44±0.53 (Snellen’s equivalent-2/60), p=<0.0001. Group 1-1.9±0.13 to 1.43+0.45 {p value=0.0001} and Group2: 1.86±0.11 to 1.45±0.61 {p value=0.0056}. There was no difference between the two groups. On comparing the mean gain in BCVA in cases of TRD involving macula- Group1: 0.54+0.4 and Group2: 0.26+0.56; p value=0.0503. In patients with TRD threatening macula- Group1-0.19+0.58 and Group2-0.6+0.71; p value=0.18). There was no statistically significant difference in rates of rebleed (early vitreous hemorrhage: p value=1; delayed vitreous hemorrhage: p val ue=0.636), persisting macular traction/ residual tractional retinal detachment (p value=0.55), post vitrectomy rhegmatogenous retinal detachment (p value=0.636), repeat vitreoretinal surgery (p value=0.636), macular ischemia (p value= 0.381), diabetic macular edema (p value=0.546), epiretinal membrane (p value=0.636).

Conclusions:

Bimanual vitrectomy with chandelier endoillumination is not essential in all cases but in cases of complex diabetic tractional retinal detachment cases – it is a safe and useful alternative modality of treatment as it reduces the membrane removal time and hence, the whole surgical time. It provides good anatomical and functional results with no additional intraoperative complications.

Limitations:

Another study with larger sample size, pre operative classification system for ascertaining the complexity of TRD and longer follow up is required to document the further advantages of chandelier endoillumination.


CONTACT DETAILS

Itika Garg
New Delhi, India
Email : itikagarg@gmail.com
Cell Phone: +919560004430
Work Phone: +919560004430