A growing population of over 10 million people worldwide with vision-threatening complications of diabetes and over 50 million people with ocular hypertension require treatments with retinal laser photocoagulators
. However, approximately 40% of these procedures cannot be completed in one session due to inflammation.
We then identified an equal number of consecutive eyes using the same inclusion criteria, except that PRP was performed using a conventional argon laser with either direct ophthalmoscopy before acquisition of the pattern scan photocoagulator, PASCAL (April 2013 or earlier).
For the conventional argon group (Conv group), a retinal photocoagulator MC-300 (NIDEK, Co.
SPL was used with the PASCAL photocoagulator (Optimedica Corporation, Santa Barbara, CA, USA), which uses a frequency-doubled neodymium-doped yttrium aluminum garnet solid-state laser with a wavelength of 577 nm.
Laser photocoagulation was performed on each group using the PASCAL photocoagulator in yellow wavelength (577 nm) and Super Quad 160 contact lens.
Techniques of treatment have also evolved considerably over time; for example early photocoagulators
produced intense burns with significant damage to the nerve fibre layer, with corresponding visual field defects (Figures 1a and b), but over time gentler laser application, including technologies such as micropulse diode to limit collateral tissue damage, have lessened treatment side effects.