The Pascal method of photocoagulation allows the delivery of a predetermined pattern by scanning the placement of the laser spots and controlling the emission of the laser light to high degrees of accuracy and precision. This laser system (PASCAL; OptiMedica Inc.) provides 532-nm light through a multimode step index optical fiber to an integrated galvanometer-based optical scanner housed within a slit lamp biomicroscope. The exit surface of the fiber is telecentrically imaged through the scanning system onto the retina, providing a variety of spot sizes with nominally top-hat intensity profiles. At the aerial image plane of the slit lamp microscope, the laser spots measure 60, 100, 200, and 500 μm in diameter, all at the same numerical aperture. Different core diameter fibers are used to produce the different spots. Pulse durations from 10 to −1,000 ms are available. These optical pulses have 10 μs rise and fall times and a temporal power stability of greater than 90%. A touch-screen graphic user interface is used to control treatment parameters, including the spot size, laser power, pulse duration, and pattern geometry. Once the treatment parameters are appropriately selected, a foot pedal is used to activate the laser. The Pascal Photocoagulator enables the physician to deliver multiple laser lesions with a single footswitch depression by automating the emission of laser light with as much as 56 pulses within half a second.

The PASCAL laser utilizes short-duration pulses (20-30 ms) to limit thermal diffusion (1). Anterior thermal diffusion can create damage to the nerve fiber layer. Posterior thermal diffusion heats the choroid, causing pain and even choroidal edema (effusion). Lateral thermal diffusion is the most observable and clinically significant issue because it results in “RPE creep,” enlargement of lesions over time causing loss of central visual function. The PASCAL laser utilizes a three-galvanometer system to rapidly produce a precise pattern with programmable interlesion spacing. Lighter intensity, smaller, more numerous spots with precise spacing produce the best outcomes and can be produced in a shorter time because of the scanning system.

Though roughly 70% of the population develops a posterior vitreous detachment (2), only about 4% of the population has retinal breaks (3). Of these patients, only about 6 in 10,000 develop retinal detachments. Patients go on to develop retinal detachment after retinopexy in about 2% of cases, with the complication rate of retinopexy remaining exceedingly low and difficult to measure (4). Determining the need for treatment is multifactorial and complex at best.

The most conservative position is that only symptomatic flap tears should be treated (5). However, many large horseshoe tears, which all surgeons would agree need treatment, are asymptomatic as many surgeons have discovered in examinations carried out before laser-assisted in situ keratomileusis (LASIK) and even routine examinations (6).

Clinical characteristics in favor of treatment include larger breaks, flap tears instead of round holes, breaks outside lattice, superior location, and evidence of vitreous traction (7

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