Comparison of Pain Scores Among Patients Undergoing Conventional and Novel Panretinal Photocoagulation for Diabetic Retinopathy: A Systematic Review

Figures & data

Table 1 Characteristics of Included Studies

Study ID	Methods	Participants	Interventions	Outcomes	Notes
Comparison 1: Conventional Multi-spot versus Conventional Single-Spot
Muqit 2010^Citation35	RCT	Setting: Manchester Royal Eye Hospital Participants: 24 patients (40 eyes) Mean age (years): 45.7 ± 9.7 (MSL) 45.8 ± 10.5 (SSL)	MSL: PASCAL® 532 nm SSL: PASCAL® 532 nm Anesthetic: 0.4% oxybuprocaine eye drops Other notes: Independent randomization of right and left eyes for bilateral cases Delay between treatment of one eye and the other	Primary: Pain score (NPS, mean of 3 sessions, 3 measurements per session) Secondary: Duration of pain responses, NHS score at 1 month, affective changes post-treatment, levels of photophobia post-PRP, adverse events	Funding: Optimedica Corporation, Santa Barbara, USA Conflict of Interest: One author is an employee of the Optimedica Corporation, one author received financial support from Optimedica Corporation
Nagpal 2010^Citation7	RCT	Setting: No information Participants: 60 patients (120 eyes) Mean age (years): 52 (45 - 61)	MSL: PASCAL® 532 nm SSL: Solid-state green Laser/ GLX 532 nm Other notes: Each patient experienced both modalities on the same day; time interval in between not specified	Regression of retinopathy, complications of PRP, change in laser spot size, retinal visual field sensitivity, total time required for complete PRP, pain score (VAS)	Funding: No financial disclosures Conflict of Interest: None
Yang 2010^Citation20	RCT	Setting: No information Participants: 80 patients (150 eyes) Mean age (years): 60.03 ± 13.66 (MSL) 58.78 ± 11.30 (SSL)	MSL: PASCAL® 532 nm SSL: PASCAL® 532 nm	Laser parameters, progression of diabetic retinopathy, visual acuity, central macular thickness, pain score (VAS), complications	Funding: No information Conflict of Interest: No information
Muraly 2011^Citation39	RCT	Setting: Aravind Eye Hospital Participants: 50 patients (100 eyes) Mean age (years): 57.44 ± 8.98	MSL: PASCAL® 532 nm SSL: Nd-YAG laser 532 nm	Pain score (graded by physician – mild, moderate, severe), retreatment, regression and persistence of neovascularization, vitreous hemorrhage	Funding: No financial disclosures Conflict of Interest: None
Salman 2011^Citation41	RCT	Setting: No information Participants: 120 patients (120 eyes) (50% of study population excluded from this review) Mean age (years): 48.9 ± 9.3	MSL: PASCAL® 532 nm SSL: Novus Spectra Green-light Diode Pumped Solid State Photocoagulator (Lumenis) 532 nm	Treatment parameters, treatment efficacy, visual acuity, procedure length, pain score (0 to 5), adverse events	Funding: Ophthalmology Department, Ain Shams University Conflict of Interest: None
Chhablani 2015^Citation34	RCT	Setting: L V Prasad Eye Institute, Hyderabad, India and King Khaled Eye Specialist Hospital Riyadh, Saudi Arabia Participants: 47 patients (74 eyes) Mean age (years): 52.8 (42 - 63)	MSL: PASCAL® 532 nm SSL: PASCAL® 532 nm	Laser parameters, visual acuity, regression and/or development of neovascularization, need for additional treatment, pain score (VAS), treatment time	Funding: No funding Conflict of interest: Two authors have disclosed potential conflicts of interest
Zhang 2017^Citation38	RCT	Setting: Affiliated Eye Hospital of Nanjing Medical University Participants: 32 patients (40 eyes) Mean age (years): MSL: 46.5 ± 9.6 SSL: 50.2 ± 11.2	MSL: SupraScan® 577 nm SSL: SupraScan® 577 nm Other notes Standardized instruction in ranking pain scores	Changes on fundus fluorescein angiography, duration of session, pain score (0 to 3)	Funding: No information Conflict of Interest: No information
Inan 2018^Citation11	RCT	Setting: No information. Participants: 28 patients (56 eyes) Mean age (years): 61.36 ± 9.10	MSL: PASCAL® 532 nm SSL: ELLEX 532 nm Other notes: PASCAL on one eye and conventional SSL on the other eye on the same day (random order) Pain scores collected in 1 of 4 sessions wherein both eyes were treated with a 30-minute interval in between; the total duration of treatment was shorter than the others; # of laser shots were less than the usual	Pain score (VAS and Verbal Score) Note: Authors reported that the VAS scale was used, but the figures in the paper showed that they actually used a Numerical Rating Scale and a Faces Pain Scale.	Funding: No financial support Conflict of Interest: None
Nemcansky 2019^Citation40	RCT	Setting: Ophthalmology Clinic, Faculty Hospital Ostrava Participants: 30 patients (60 eyes) Mean age (years): No information	MSL: PASCAL® SSL: PASCAL® Other notes: PASCAL first on one eye and conventional SSL on the other eye	Laser parameters, stability of clinical findings, DME progression, pain score (0-8), complications	Funding: No financial support Conflict of Interest: None
Passos 2019^Citation37	RCT	Setting: Single-center Participants: 41 patients (41 eyes) Mean age (years): MSL: 56.2 ± 10.4 SSL: 61.2 ± 7.4	MSL: SupraScan® 577 nm SSL: PASCAL® 532 nm	Primary: BCVA, central retinal thickness, laser parameters, pain score (0 – 10 scale from McGill Pain Questionnaire) Secondary: OCT changes, FA findings	Funding: No financial support Conflict of Interest: Two authors received travel grants from Quantel Medical
Ahmed 2020^Citation18	RCT	Setting: Aswan university hospital (MSL); Aswan eye & laser center (SSL) Participants: 60 patients (80 eyes) Mean age (years): 54.47 ± 8.72	MSL: PASCAL® 532 nm SSL: Green-light Diode Solid State photocoagulator laser 532 nm (ELLEX) Anesthetic: 0.5% proparacaine hydrochloride drops	Primary: Pain score (mean value of numerical rating pain score (0 to 10) and the Wong-Baker Faces Pain Rating Scale), laser parameters Secondary: Complications	Funding: No information Conflict of interest: No information
Seymenoğlu 2013^Citation21	CCT	Setting: Celal Bayar Üniversitesi Participants: 70 patients (70 eyes) Mean age (in years): MSL: 61.9 ± 7.98 SSL: 64.22 ± 5.85	MSL: PASCAL® 532 nm SSL: GYC 1500 532 nm Anesthetic: 0.5% proparacaine hydrochloride drops	Primary: Pain scores (VAS, verbal pain score (0-4)) Secondary: Relationship between pain level and patient characteristics, neovascularization	Funding: No information Conflict of interest: No information
Yilmaz 2016^Citation42	CCT	Setting: Beyoglu Eye Training and Research Hospital, Istanbul, Turkey Participants: 40 patients (40 eyes) Mean age (in years): MSL: 63.7 ± 3.2 SSL: 62.5 ± 3.3	MSL: PASCAL® SSL: VISULAS 532 nm Anesthetic: Unspecified topical anesthesia	Primary: Pupil diameters in scotopic, mesopic, and photopic conditions before and after the PRP Secondary: Pain scores (0 to 10 on a 10 cm scale; equivalent to VAS)	Funding: No information Conflict of interest None
Comparison 2: Novel Navigated Laser versus Conventional Multi-Spot Laser
Chhablani 2015^Citation34	RCT	Setting: L V Prasad Eye Institute, Hyderabad, India and King Khaled Eye Specialist Hospital Riyadh, Saudi Arabia Participants: 47 patients (74 eyes) Mean age (years): 52.8 (42 - 63)	NNL: NAVILAS® 532 nm SSL: PASCAL® 532 nm	Laser parameters, visual acuity, regression and/or development of neovascularization, need for additional treatment, pain score (VAS), treatment time	Funding: No funding Conflict of interest: Two authors have disclosed potential conflicts of interest
Inan 2016^Citation19	RCT	Setting: No information Participants: 60 patients (60 eyes) Mean age (in years): Age 62.22 ± 9.19	NNL: NAVILAS® MSL: PASCAL®	Pain scores (VRS and VAS)	Funding: No funding Conflict of interest: None
Amoroso 2019^Citation8	CCT	Setting: University Eye Clinic of Creteil (France) Participants: 16 patients (32 eyes) Mean age (in years): 57 + 13	NNL: NAVILAS® 577 nm MSL: SupraScan 577 nm Other notes: Session with each laser treatment carried out on the same day, 30 minutes apart	Pain score (VAS), duration of PRP, laser parameters, spot coverage and characteristics	Funding: No funding Conflict of interest: None
Comparison 3: Novel Navigated Laser versus Conventional Single-Spot Laser
Chhablani 2015^Citation34	RCT	Setting: L V Prasad Eye Institute, Hyderabad, India and King Khaled Eye Specialist Hospital Riyadh, Saudi Arabia Participants: 47 patients (74 eyes) Mean age (years): 52.8 (42 - 63)	NNL: NAVILAS® 532 nm SSL: PASCAL® 532 nm	Laser parameters, visual acuity, regression and/or development of neovascularization, need for additional treatment, pain score (VAS), treatment time	Funding: No funding Conflict of interest: Two authors have disclosed potential conflicts of interest
Polat 2019^Citation36	RCT	Setting: No information Participants: 70 patients (140 eyes) Mean age (in years): 63.14 ± 9.23	NNL: NAVILAS® 532 nm SSL: ELLEX 532 nm Other notes: Session with each laser treatment carried out on the same day, 30 minutes apart	Pain scores (VAS, VRS), laser parameters	Funding: No information Conflict of interest: None
Kim 2014^Citation22	CCT	Setting: Sanggye Paik Hospital, Seoul, Korea Participants: 15 patients (15 eyes) Mean age (in years): 58.3 (47 - 76)	MSL: NAVILAS® SSL: OcuLight® 532 nm Anesthetic: 0.5% proparacaine	Pain score (VAS), duration of treatment Note: “VAS” used appears to be “NRS” based on the publication	Funding: No information Conflict of Interest: No information

Note: Bold: Pain outcome.

Abbreviations: RCT, randomized controlled trial; MSL, multi-spot laser; SSL, single spot laser; nm, nanometers; NPS, numerical pain score; NHS, numerical headache scores; PRP, panretinal photocoagulation; PASCAL, Pattern Scanning Laser; VAS, visual analog scale; Nd:YAG, Neodymium-doped:Yttrium Aluminum Garnet; BCVA, best-corrected visual acuity; VRS, verbal rating score; CCT, controlled clinical trial.

Table 2 Inclusion and Exclusion Criteria of Included Studies

Study ID	Inclusion Criteria	Exclusion Criteria
Comparison 1: Conventional Multi-Spot Laser versus Conventional Single-Spot Laser
Muqit 2010^Citation35	Newly diagnosed PDR, Type 1 or 2 DM, > 18 years old, VA 6/60 or better, mean CRT < 300 μm by OCT with no intraretinal or subretinal fluid, adequate pupil dilation, clear media, ability to perform Humphrey visual field test	Poor glycemic control (HbA1c > 10 mg/dL), uncontrolled hypertension (BP ≥ 180/110), history of chronic renal failure or renal transplant for diabetic nephropathy, lens opacity or cataract that could influence vision or results, any previous surgical or laser treatment to study or fellow eye, history of DME in study or fellow eye, previous ocular condition that may be associated with risk of macular edema, active lid or adnexal infection, previous retinal treatment (laser, drug or surgery), planned intra-ocular surgery within 1 year
Nagpal 2010^Citation7	Bilaterally symmetrical PDR or NPDR severe	History of previous laser treatments and/or intravitreal injections in either eye, pre-treatment BCVA of <6/24, media opacities obscuring the fundus in either eye, diabetic maculopathy, glaucoma, uveitis, retinitis pigmentosa, myopia greater than −6 diopters, retinal degenerations and dystrophies, optic disc pathologies
Yang 2010^Citation20	NPDR severe	Previous PRP, media opacity (cataract, vitreous bleeding), age-related macular degeneration, epiretinal membrane, macular diseases, glaucoma, retinal vessel obstruction, ophthalmic surgery within the last 6 months, intravitreal anti-VEGF injection, severe macular edema, macular traction
Muraly 2011^Citation39	Early and high-risk PDR of both eyes, PDR with 2–4 high risk characteristics, age ≥ 18 years old, BCVA 6/60 or better	Vitreous hemorrhage obscuring view, vision in only one eye or those in whom only one eye had PDR/PDR HR, maculopathy, tractional retinal detachment, media clarity inadequate, previous laser, poor follow-up, uncontrolled systemic parameters (high blood pressure, blood sugar, nephropathy)
Salman 2011^Citation41	PDR, NPDR with need for laser, Type 2 DM with need for laser, able to sign consent	Ischemic maculopathy, previous laser or intravitreal injection, vitrectomy or associated retinal diseases such as retinal vein occlusion
Chhablani 2015^Citation34	PDR HR, Type 1 or 2 DM, ≥ 18 years old	Low-risk PDR, monocular status, poor compliance, pregnant, history of prior PRP or vitrectomy, history of anti-angiogenic injections within the previous 2 months, evidence of center-involved DME, intravitreal dexamethasone implant, media opacities obscuring fundus details, coagulation abnormalities, use of anticoagulants other than aspirin
Zhang 2017^Citation38	Newly diagnosed PDR HR	No information
Inan 2018^Citation11	Bilateral PDR HR, Type 1 or 2 DM	Previous focal/grid photocoagulation, history of orbital trauma, orbital infection or surgery, corneal or lens opacities, vitreous hemorrhage, non-compliance
Nemcansky 2019^Citation40	NPDR severe, PDR	Previous retinal laser photocoagulation, vitrectomy, associated vascular retinal diseases
Passos 2019^Citation37	Treatment-naïve severe NPDR or PDR, Type 1 or 2 DM, ≥ 18 years old, ability to understand and sign a written consent form	History of intravitreal injections during the previous 6 months, vitrectomy, or any ocular comorbidity
Ahmed 2020^Citation18	Newly diagnosed PDR, Type 1 or Type 2 DM, >18 years old, Snellen BCVA of 6/60 or better, adequate pupil dilation, clear media	Previous laser photocoagulation or macular laser treatment on the study eye, recent intraocular surgery (within 3 months), media opacities that interfere with evaluation of the posterior segment, mean central macular thickness > 300 microns by OCT, contraindication to fluorescein angiography, poor glycemic control (HbA1c > 10 mg/dL), uncontrolled hypertension, BP ≥ 180/110 mm/Hg, vitreoretinal traction, indication/plan for intraocular surgery within 6 months
Seymenoğlu 2013^Citation21	PRP-naïve PDR, > 18 years	No information
Yilmaz 2016^Citation43	PDR	Ocular disease other than diabetic retinopathy, systemic disorders other than diabetes, diabetic macular edema, advance proliferative diabetic retinopathy (NVI, NVG, RD), history of intraocular surgery, active lid or adnexal infection, history of previous retinal laser therapy or intravitreal injection, history of systemic medications in the last 3 months, history of ocular medications during the last year, history of ocular or head trauma, smokers and heavy alcoholic drinkers
Comparison 2: Novel Navigated Laser versus Conventional Multi-Spot Laser
Chhablani 2015^Citation34	See above.	See above.
Inan 2016^Citation19	PDR HR, Type 1 or 2 DM, > 18 years	PDR low risk, poor compliance, pregnant, history of focal/grid photocoagulation or PRP, orbital trauma or surgery, inflammatory signs, significantly increased corneal or lens thickness, vitreous hemorrhage
Amoroso 2019^Citation8	Bilateral pre-PDR or PDR eligible for PRP, treatment-naïve, ≥ 18 years old	Intravitreal hemorrhage, media opacities inhibiting laser treatment
Comparison 3: Novel Navigated Laser versus Conventional Single-Spot Laser
Chhablani 2015^Citation34	See above.	See above.
Polat 2019^Citation36	PDR, Type 1 or 2 DM, > 18 years old	History of vitrectomy or ocular trauma, active or history of intraocular inflammation, media opacities obscuring fundus details or affecting power parameters, mental or visual deficiency and inability to express pain on pain scales
Kim 2014^Citation22	PDR	Previous retinal photocoagulation, corneal opacity, cataract, vitreous hemorrhage, media opacity

Abbreviations: PDR, proliferative diabetic retinopathy; DM, diabetes mellitus; VA, visual acuity; CRT, central retinal thickness; μm, micrometers; OCT, optical coherence tomography; BP, blood pressure; DME, diabetic macular edema; NPDR, non-proliferative diabetic retinopathy; BCVA, best-corrected visual acuity; PRP, panretinal photocoagulation; VEGF, vascular endothelial growth factor; HR, high risk; NVI, neovascularization of the iris; NVG, neovascular glaucoma; RD, retinal detachment.

Figure 1 Search yield.

Table 3 Laser Parameters in Included Studies

Study ID	Machine	Spot Size	Duration	Power (mW)	# of Burns	# of Sessions
Comparison 1: Conventional Multi-Spot versus Conventional Single-Spot Laser
Muqit 2010^Citation34	MSL: PASCAL^® 532 nm	MSL: 400 μm	MSL: 20 ms	MSL: 287 ± 71	MSL: 1500	MSL: 1
	SSL: PASCAL^® 532 nm	SSL: 400 μm	SSL: 100 ms	SSL: 142 ± 22	SSL: 1500	SSL: 3
				Fluence (J/cm^2):
				MSL: 4.8
				SSL: 11.8
Nagpal 2010^Citation7	MSL: PASCAL^® 532 nm	MSL: 200 μm	MSL: 20 ms	MSL: 630 (40–1000)	MSL: 1093 (950–1100)	MSL: 2
	SSL: Solid state green laser (GLX) 532 nm	SSL: 200 μm	SSL: 200 ms	SSL: 288 (200–400)	SSL: 575 (500–700)	SSL: 2
				Fluence (J/cm^2):
				MSL: 40.33
				SSL: 191
Yang 2010^Citation20	MSL: PASCAL^® 532 nm	MSL: 200 μm	MSL: 20 ms	MSL: 468.83 ± 106.08	MSL: 1728.90 ± 324.39	MSL: 1
	SSL: PASCAL^® 532 nm	SSL: 200 μm	SSL: 200 ms	SSL: 307.10 ± 12.18	SSL: 1624.92 ± 511.92	SSL: 3
				p = 0.01
				Fluence (J/cm^2):
				MS: 26.21 ± 7.29
				SS: 189.4 ± 45.33
Muraly 2011^Citation39	MSL: PASCAL^®	MSL: 400 μm	MSL: 20–30 ms	MSL: 439 (275–950)	MSL: 2795 (2100–3892)	MSL: 1
	SSL: Nd:YAG laser 532 nm	SSL: 400 µm	SSL: 200 ms	SSL: 192.8 (125-300)	SSL: 1414 (1200-1672)	SSL: 2–3
Salman 2011^Citation41	MSL: PASCAL^® 532 nm	MSL: 400 μm	MSL: 20 ms	MSL: 410 ± 115.2	MSL: 1090 ± 410.4	MSL: 1–2
	SSL: Novus Spectra Green-light Diode Pumped Solid State Photocoagulator (Lumenis) 532 nm	SSL: Not stated	SSL: 100 ms	SSL: 215 ± 51.3	SSL: 700 ± 201.1	SSL: 1–3
Chhablani 2015^Citation34	MSL: PASCAL^® 532 nm	MSL: 200 μm	MSL: 20–30 ms	MSL and SSL:	MSL: 2334 ± 656	More than one (35–47% of all groups needed retreatment)
	SSL: PASCAL^® 532 nm	SSL: 200 μm	SSL: 100–200 ms	200–400 mW	SSL: 1433 ± 513
				(No significant difference)
Zhang 2017^Citation38	MSL: SupraScan^® 577 nm	MSL: 200–300 μm	MSL: 35–50 ms	MSL: 450–800 mW	No information	MSL: 3
	SSL: SupraScan^® 577 nm	SSL: 200–300 μm	SSL: 250–300 ms	SSL: 250–450 mW		SSL: 4
Inan 2018^Citation11	MSL: PASCAL 532 nm	MSL: 200–400 μm	MSL: 30 ms	Not reported	MS: 435.36 ± 77.46	MSL: 4
	SSL: ELLEX 532 nm	SSL: 200–400 μm	SSL: 100 ms		SS: 436.18 ± 74. 63	SSL: 4
					(per session)
Nemcansky 2019^Citation40	MSL: PASCAL^®	MSL: 400 μm	MSL: 20 ms	MSL: 473 ± 128	MSL: 2113 ± 328	MSL: 1–2
	SSL: PASCAL^®	SSL: 400 μm	SSL: 200 ms	SSL: 295 ± 96	SSL: 1685 ± 179	SSL: >1–3
Passos 2019^Citation37	MSL: SupraScan^® 577 nm	MSL: 400 μm	MSL: 20 ms	MSL: 451.4 ± 138.0	MSL: 2504 ± 377.3	MSL: 2.7 ± 0.6
	SSL: PASCAL^® 532 nm	SSL: 400 μm	SSL: 100 ms	SSL: 356 ± 136.5	SSL: 1287.6 ± 187.6	SSL: 3.9 ± 0.7
Ahmed 2020^Citation18	MSL: PASCAL^® 532 nm	MSL: 200 μm	MSL: 20 ms	MSL: 525 ± 125.4	MS: 2820.63 + 394.18	MS: 2.0 ± 0
	SSL: ELLEX 532 nm	SSL: 200 μm	SSL: 100 ms	SSL: 260 ± 130.7	SS: 2611.42 + 285.61	SS: 2.1 ± 0.3
Seymenoğlu 2013^Citation21	MSL: PASCAL^® 532 nm	MSL: 200 μm	MSL: 20–30 ms	MSL: 650 (250–1500)	MS: 2885 (2100–3951)	MSL: 1
	SSL: GYC 1500 532 nm	SSL: 200 μm	SSL: 200 ms	SSL: 330 (200–600)	SS: 1642 (1364–1948)	SSL: 2
Yilmaz 2016^Citation42	MS: PASCAL	MSL: 400 μm	MSL: 20–30 ms	MSL: 528 ± 68	MSL: 2018 ± 132	MSL: 1
	SSL: VISULAS 532 nm	SSL: 400 μm	SSL: 200–400 ms	SSL: 242 ± 42	SSL: 1812 ± 142	SSL: 3–4
Comparison 2: Novel Navigated Laser versus Conventional Multi-Spot Laser
Chhablani 2015^Citation34	NNL: NAVILAS^® 532 nm	NNL: 300 μm	NNLS: 20–30 ms	NNL and MSL:	NNLS: 1810 ± 369	More than one (35–47% of all groups needed retreatment)
	MSL: PASCAL^® 532 nm	MSL: 200 μm	NNLL: 100–200 ms	200–400 mW	NNLL: 1120 ± 446
			MSL: 20–30 ms		MSL: 2334 ± 656
Inan 2016^Citation19	NNL: NAVILAS^®	NNL: 200–400 μm	NNL: 30 ms	No information.	NNL: 389.47 ± 71.52	NNL: 1
	MSL: PASCAL^®	MSL: 200–400 μm	MSL: 30 ms		MSL: 392.7 ± 54.33	MSL: 1
Amoroso 2019^Citation8	NNL: NAVILAS^® 577 nm	NNL: 390 μm	NNL: 20 ms	NNL: 304.6 (300–350)	NNL: 1774 (964–2504)	NNL: 1
	MSL: SupraScan 577 nm	MSL: 390 μm	MSL: 20 ms	MSL: 306.8 (300–350)	MSL: 1778 (1049–2549)	MSL: 1
Comparison 3: Novel Navigated Laser versus Conventional Single-Spot Laser
Chhablani 2015^Citation34	NNL: NAVILAS® 532 nm	NNL: 300 μm	NNLS: 20–30 ms	NNL and MSL:	NNLS: 1810 ± 369	More than one (35–47% of all groups needed retreatment)
	MSL: PASCAL^® 532 nm	SSL: 200 μm	NNLL: 100–200 ms	200–400 mW	NNLL: 1120 ± 446
			SSL: 100–200 ms		SSL: 1433 ± 513
Polat 2019^Citation36	NNL: NAVILAS^® 532 nm	NNL: 200–400 μm	NNLS: 30 ms	NNL: 291.9 + 85.3	NNL: 375.4 ± 108.4	NNL: 4
	SSL: ELLEX 532 nm	SSL: 200–400 μm	NNLL: 100 ms	SSL: 368.4 ± 72.0	MSL: 374.2 ± 105	MSL: 4
			SSL: 100 ms
Kim 2014^Citation22	MSL: NAVILAS^®	No information	NNL: 30 ms	NNL: 373.3 ± 38.1	NNL: 2055.2 ± 288.7	NNL: 1
	SSL: OcuLight^® GL		SSL: 100 ms	SSL: 209.3 ± 20.5	SSL: 658.8 ± 65.3	SSL: No information

Abbreviations: mW, milliwatts; MSL, multi-spot; SSL, single-spot; nm, nanometers; μm, micrometer; ms, millisecond; J, joules; cm², square centimeters; NNL_S, short-pulse novel navigated laser; NNL_L, long-pulse novel navigated laser.

Figure 2 Risk of bias assessment of included RCTs.

Figure 3 Risk of bias assessment of included CCTs.

Figure 4 Forest plot comparing conventional MSL and conventional SSL.

Figure 5 Forest plot comparing NNL and conventional MSL (Pulse duration: 30-ms).

Figure 6 Forest plot comparing long-pulse NNL and conventional SSL (pulse duration: 100-ms).

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