PANRETINAL PHOTOCOAGULATION
Increase PRP Efficiency With Pattern-based Photocoagulation
The new laser will help reduce patient discomfort, reduce the number of sessions and shorten treatment time.

The concept of treating the retina with uniform laser burns to achieve panretinal photocoagulation (PRP) has been around for a long time, but a new technology may have the potential to improve the experience for physicians and patients.

The PASCAL laser (OptiMedica, Santa Clara, Calif.), can perform PRP for the treatment of various retinal diseases, such as proliferative diabetic retinopathy (PDR), as well as grid laser for diabetic macular edema (DME) in unique ways, said Harry W. Flynn, Jr., MD, of Bascom Palmer Eye Institute, at the May 2006 Retinal Physician Symposium.

PASCAL, an acronym for Pattern Scan Laser is a 532-nm laser that has the ability to apply a uniform pattern of laser burns, using either a single spot or a predetermined pattern of up to 25 spots in 0.5 seconds, Dr. Flynn explained. The system allows delivery of a predetermined pattern by scanning the placement of the laser spots and controlling the emission of the laser light.

The development of the PASCAL laser, Dr. Flynn added, resulted from a quarter-century-old concept that it's not how heavily you treat the retina, it's how uniformly you apply the treatment in all areas while avoiding the macula. The goal is to achieve regression of new vessels and reduce rates of vitreous hemorrhage.

Touch-screen technology enables physicians to choose standard single-spot PRP or a grid pattern.

SHORTER SESSIONS, LESS PAIN

Preclinical animal models and pilot studies in humans show the PASCAL laser may reduce the number of PRP sessions and shorten treatment time. Laser treatment with the PASCAL is facilitated with short duration burns and multiple spot placements, so "completing PRP in just one session is feasible," Dr. Flynn said.

What's more, patients may experience less pain following surgery. The laser can deliver precise, uniform burns to the retina, using milliseconds versus longer burns, with perhaps less energy applied to the choroid. "Theoretically, having less uptake of energy by the choroid may make it more comfortable for patients, but pain is subjective and difficult to quantitate," Dr. Flynn said. Another benefit: The PASCAL laser has a predictable burn size that allows ophthalmologists to apply more precise, preselected treatment patterns in patients with diffuse DME.

TWO DISTINCT PATTERNS

Physicians also can choose standard single-spot PRP or a grid pattern, using touch-screen technology. "You just touch your finger to the monitor and select a wedge of treatment. By running your finger across the touch screen array, you can change the pattern to suit the pattern of edema for the patient," Dr. Flynn said.