Session Title: Vitreoretinal Surgery III
Session Date/Time: Friday 27/09/2013 | 11:00-12:30
Paper Time: 11:16
Venue: Hall 3 (Level 0)
First Author: E.Papavasileiou UK
Co Author(s): V. Zygoura H. Laviers H. Zambarakji
Morphological assessment of the vitreomacular interface and intraretinal architecture using SD-OCT before and after surgical delamination of epiretinal membranes in patients with advanced PDR
Whipps Cross University Hospital, London
18 eyes of 17 consecutive patients were operated by a single surgeon over one year period and had vitrectomy and membrane delamination for TRD secondary to PDR. Retinal architecture was assessed using OCT imaging. Standardized follow-up examinations were performed prospectively at 1 week, 1 month, 3 months and at last clinic visit after surgery. Macular function was tested by assessing logMAR distance visual acuity (VA) using the logMAR Thompson vision chart. Main outcome measures included VA and OCT findings. OCT assessment included automated central 1-mm subfield retinal thickness (CFT), integrity of photoreceptor inner and outer segments (IS/OS), presence of epiretinal membrane, subretinal fluid (SRF) and cystoid macular oedema (CMO). Two OCT-trained masked observers independently graded the OCT findings.
Mean age of patients was 49 years (range: 34-70 years). Mean follow up was 6.1 months.The agreement between the two readers was 95.3%. Mean pre-operative VA was 1.0 (range: 2.1 - 0.18) and mean postoperative VA improved to 0.78 (range: 2.1 to 0.0; P<0.0001). Mean post-op IS/OS integrity was present in 59%. Post-operative VA correlated poorly with CFT (r=0.5; p=0.17), ERM ( p=0.35), SRF (p=0.15) and CMO (p=0/07). The only SD-OCT variable that correlated with VA was IS/OS integrity (p=0.002).
Limitations of the study are the small numbers, the absence of controls and the limited availability of preoperative OCT scans. In conclusion the integrity of the outer retinal microstructure appears to be an important biomarker of visual performance following PPV and membrane delamination for PDR.