Abstract
Purpose:
To compare the effects of ETDRS standard panretinal photocoagulation (Single Spot; SS-PRP group) plus intravitreal injection of 0.5 mg of ranibizumab (IVR) with PASCAL PRP (Multiple Spots; MS-PRP group) plus IVR with only IVR (IVR group) in patients with proliferative diabetic retinopathy (PDR).
Methods:
Prospective study included patients with PDR and no prior laser treatment randomly assigned to receive ETDRS PRP plus IVR (SS-PRP group) or PASCAL PRP plus IVR (MS-PRP group) or only IVR (IVR group). ETDRS-PRP was administered in two sessions (weeks 0 and 1) and PASCAL-PRP one session (week 0). IVR was administered at the end of the first laser session in all laser groups and at week 0 in IVR group. Standardized ophthalmic evaluations including ETDRS best-corrected visual acuity (BCVA), fluorescein angiography to measure area of fluorescein leakage from active new vessels (FLA) and optical coherence tomography (OCT) for the assessment of central subfield macular thickness (CSFT), were performed at baseline and at weeks 4, 8, 12, 16, 20, 24, 28, 32, 36, 40, 44 and 48.
Results:
Thirty-one of forty five patients (n = 40 eyes) completed the 48-week study follow-up period. At baseline, mean ± SE FLA (mm2) was 21,0 ± 5,6; 17,1 ± 5,5 and 15,5 ± 5,9 (p ≥0,05); BCVA (logMAR) was 0,5 ± 0,086, 0,464 ± 0,086 and 0,492 ± 0,093 (p ≥0,05); and CSFT (µm) was 283,4 ± 24,1; 369 ± 24,1 and 318,0 ± 26 (p ≥0,05), in the SS-PRP, MS-PRP and IVR groups, respectively. There was a significant (p < 0.05) FLA reduction at all study visits in all groups. BCVA significantly improved at all visits in IVR group; at weeks 8, 12, 16, 20, 24, 28, 32, 36, 40, 44 and 48 in SS-PRP and at weeks 16, 20, 24, 28, 32, 40, 44 and 48 in MS-PRP group. A significant CSFT decrease was observed in the MS-PRP group at weeks 4, 8 and 48; only at week 48 in the IVR group and none in the SS-PRP group. There wasn`t significant difference among these groups regarding FLA reduction, CSFT reduction and BCVA change (p<0.05). The mean number of intravitreal injections of Ranibizumabe was 9,5 ± 1,13; 13,4 ± 1,13 and 10,3 ± 1,22 in the SS-PRP, MS-PRP and IVR groups, respectively.
Conclusions:
In this 48-week study, IVR alone or combined with single or multiple spot PRP had similar results regarding FLA, BCVA improvement and CSFT reduction.