Extended targeted retinal photocoagulation versus conventional pan-retinal photocoagulation for proliferative diabetic retinopathy in a randomized clinical trial.
OBJECTIVE
To determine the clinical efficacy of extended targeted retinal photocoagulation (ETRP) compared to conventional panretinal photocoagulation (CPRP) in proliferative diabetic retinopathy (PDR).


METHODS
In a single-masked randomized clinical trial, 270 eyes of 234 patients with naïve early or high-risk PDR were randomly assigned to receive either CPRP or ETRP (135 eyes, each treatment arm). Best-corrected visual acuity (BCVA) measurement, fundus examination, wide-field fluorescein angiography (WFFA) and optical coherence tomography were carried out before and 3 months after retinal photocoagulation. Primary outcome was early PDR regression, specified as reduction in retinal neovascularization based on WFFA at 3 months. Secondary outcomes were BCVA and central macular thickness (CMT) changes.


RESULTS
There were significantly more high-risk PDR eyes in ETRP group compared to CPRP (109 and 94 eyes, respectively, P = 0.04). Early PDR regression occurred in 71.9 and 64.4% of eyes in the ETRP and CPRP groups, respectively (P = 0.19). The mean number of applied laser spots in the ETRP was significantly fewer than CPRP (1202 vs. 1360, respectively, P < 0.001). Mean BCVA at baseline and 3 months post-laser were 0.37 ± 0.26 and 0.47 ± 0.19 logMAR in the ETRP arm, respectively. In the CPRP arm these values were 0.40 ± 0.27 and 0.47 ± 0.24 logMAR, respectively. Although mean BCVA decreased significantly in both treatment arms (ETRP P < 0.001, CPRP P = 0.009), the difference was not significant between arms (P = 0.68). CMT increased significantly in both groups (ETRP 41.08 μm, P < 0.001, CPRP 33.31 μm, P < 0.001). Nevertheless, the difference between the groups was not significant (P = 0.26).


CONCLUSIONS
ETRP with fewer number of laser spots may be an appropriate alternative to CPRP in PDR regression at least through 3 months.


BACKGROUND

NCT01232179.
Torfe and Imam Hossein medical centers, Shahid Beheshti University of Medical Sciences, Tehran, Iran.
Homayoun
H
Nikkhah
Ophthalmology Department and Ophthalmic Research Center, Shahid Beheshti University of Medical Sciences, Tehran, Iran.
Hossein
H
Ghazi
Ophthalmology Department and Ophthalmic Research Center, Shahid Beheshti University of Medical Sciences, Tehran, Iran.
Mohammad Reza
MR
Razzaghi
Ophthalmology Department and Ophthalmic Research Center, Shahid Beheshti University of Medical Sciences, Tehran, Iran.
Saeed
S
Karimi
Torfe and Imam Hossein medical centers, Shahid Beheshti University of Medical Sciences, Tehran, Iran.
Alireza
A
Ramezani
Ophthalmology Department and Ophthalmic Research Center, Shahid Beheshti University of Medical Sciences, Tehran, Iran. masoud_soheilian@yahoo.com.
Masoud
M
Soheilian
D000328:Adult; D000368:Aged; D003930:Diabetic Retinopathy / Q000175:diagnosis / Q000503:physiopathology / Q000601:surgery*; D004867:Equipment Design; D005260:Female; D005451:Fluorescein Angiography / Q000295:instrumentation*; D005500:Follow-Up Studies; D005654:Fundus Oculi; D006801:Humans; D021621:Imaging, Three-Dimensional; D017075:Laser Coagulation / Q000379:methods; D008028:Light Coagulation / Q000379:methods; D008297:Male; D008875:Middle Aged; D012160:Retina / Q000000981:diagnostic imaging / Q000601:surgery*; D016037:Single-Blind Method; D013997:Time Factors; D041623:Tomography, Optical Coherence / Q000295:instrumentation*; D016896:Treatment Outcome; D014792:Visual Acuity; D055815:Young Adult
Extended targeted retinal photocoagulation; Panretinal photocoagulation; Proliferative diabetic retinopathy