Abstract
Methods: :
Prospective, randomised clinical trial. PDR was treated with 1,500 burns between two groups (SS-PRP Pascal 20 ms, single session; MS-PRP single-spot 100 ms, twice-weekly over 3 sessions). ETDRS visual acuity (VA), central retinal thickness (CRT, Topcon, 3D OCT-1000), and 24-2 SITA-Std Humphrey/Estermann VFs were recorded at baseline, 1 and 3 months post-laser. Laser powers and treatment times were recorded. Paired t-test analysis was performed.
Results: :
Results reported for 24 eyes (12-SS, 12-MS). Average power used for Pascal SS-PRP was significantly higher than conventional MS-PRP (277mW-SS; 140mW-MS; p<0.0001). However, at one month, mean CRT increased significantly following MS-PRP, in comparison to SS-PRP (254.4-MS; 225.7-SS, p=0.02). In the SS-PRP group alone, CRT measured at baseline (232.6 µm) did not alter significantly after 1 month (233.6 µm, p=0.78) and 3 months (239.3 µm, p=0.95). Mean threshold VF values did not change significantly at 1 month (SS, -0.727dB, SD 2.493, n=520; MS, -0.428dB SD 4.333, n=416), or 3 months (SS, -1.381dB, SD 4.801, n=312; MS, -0.585dB, SD 2.548, n=260). No eyes were below DVLA UK driving VF standards after PRP. Mean total duration of Pascal SS-PRP was <10% of conventional single-spot MS-PRP (p<0.0001).
Conclusions: :
We report a favourable safety profile for Pascal SS-PRP compared to conventional MS-PRP. A significant increase in CRT after single-spot MS-PRP was observed at one month compared to Pascal SS-PRP, suggesting that multiple treatments may induce a prolonged inflammatory response as there may be insufficient time for the tissue to recover between each session. There were no significant changes in VF following PRP at all time points. Pascal PRP may be safely and rapidly performed with 1,500 burns in a SS.
Clinical Trial: :
www.cmmc.nhs.uk; PIN: R00037
Keywords: diabetic retinopathy • laser • imaging methods (CT, FA, ICG, MRI, OCT, RTA, SLO, ultrasound)