Abstract
Purpose: :
To evaluate the analgesic effect of oral potassium diclofenac in patients undergoing panretinal photocoagulation (PRP) for high-risk proliferative diabetic retinopathy (PDR).
Methods: :
Prospective, randomized, double-masked, placebo-controlled clinical trial in which 30 patients with bilateral high-risk PDR scheduled to undergo PRP for the first time were assigned randomly to 1 of 2 treatment protocols: treatment group 1 patients (n=15) received one 50 mg tablet of potassium diclofenac 45 minutes before the first PRP episode [diclofenac treatment episode (DTE)] at baseline to the right eye and, two weeks later, received an identical appearing tablet of saccharine (placebo) 45 minutes before the second PRP episode [placebo treatment episode (PTE)] to the left eye; treatment group 2 patients (n =15) received the same tablets in the opposite order: PTE and, two weeks later, DTE. Pain level was recorded using a Visual Analog Scale (VAS) 15 minutes after each PRP episode.
Results: :
Mean (+ SE) VAS score was significantly lower for the DTE (28 ± 3) compared to the PTE: (55 ± 4) (t-ratio = 9.04; p<0.0001). VAS score ranged from 2 to 68 for the DTE and from 10 to 90 for the PTE. Minor local adverse events related to the treatment procedure, such as mild conjunctival hyperemia and foreign body sensation, were reported in 47% (7/15) of participants after a PTE and 14% (2/15) after a DTE. These events were transient and resolved in all patients by 2-3 days after the procedure. One patient reported mild epigastralgia 24 hours after a DTE.
Conclusions: :
Fifty mg of oral potassium diclofenac was superior to placebo in reducing pain associated with PRP. Larger studies are needed to confirm our preliminary findings.
Clinical Trial: :
www.clinicaltrials.gov NCT01009021
Keywords: diabetic retinopathy • laser • retinal neovascularization