Study of clinical applications and safety for Pascal® laser photocoagulation in retinal vascular disorders

Authors


Paulo E. Stanga
Consultant Ophthalmologist and Vitreoretinal Surgeon
Honorary Reader in Ophthalmology
Manchester Royal Eye Hospital
University of Manchester
Oxford Road
Manchester M139WH
UK
Tel: + 441612761234
Fax: + 441612765555
Email: retinaspecialist@btinternet.com

Abstract.

Purpose:  To establish safe laser parameter standards for 10–30 ms Pascal® laser in clinical practice and to evaluate clinical and visual outcomes using this 532-nm multi-spot photocoagulation system.

Methods:  Retrospective observational case series of 313 patients treated between 2006 and 2008. Evaluation of eight groups: A – panretinal photocoagulation (PRP) for proliferative diabetic retinopathy (PDR); B – focal laser treatment for clinically significant diabetic macular oedema; C – grid laser for diffuse diabetic macular oedema; D – sector PRP for ischaemic branch retinal vein occlusions (I-BRVO); E – full PRP for ischaemic central retinal vein occlusions (I-CRVO); F – macular laser treatment for macular oedema secondary to non-ischaemic BRVO; G – full PRP for rubeosis iridis and/or neovascular glaucoma (NVG) secondary to I-BRVO, I – CRVO or PDR; H – laser retinopexy for retinal breaks/degenerations.

Results:  Mean LogMAR visual acuity for all procedures improved postlaser (p = 0.065), and laser prevented visual loss in 85% eyes. Topical anaesthesia was only required. At mean follow-up of 5 months, 72% procedures had a successful clinical outcome. Significantly higher powers were required for PRP using Pascal® compared to conventional laser (p = 0.001) in PDR, I-BRVO, I-CRVO and NVG. Sixty-seven per cent of patients (15/20) were successfully treated with single-session 20-ms PRP using a mean 1952 burns. There were no laser-associated adverse effects or ocular complications associated with multi-spot PRP or macular Pascal® arrays.

Conclusions:  The clinical efficacy using 10- to 30-ms pulse duration Pascal® laser is comparable to conventional standard protocols used for the treatment of vascular retinal disorders. Higher power, 10- to 30-ms pulse duration laser may be safely and effectively used in clinical practice.

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