Comparison of various laser trabeculoplasties
| SLT | MLT | TSLT | PLT | |
|---|---|---|---|---|
| Wavelength | 532 nm | 532, 577 or 810 nm | 790 nm | 532 or 577 nm |
| Spot size | 400 µm | 200–300 µm | 200 µm | 100 µm |
| Pulse duration | 3×10−9 s | 200–300×10−3 s 15% duty cycle | 5–10×10−3 s | 5–10×10−3 s |
| Energy or power per pulse | 0.6–1.2 mJ | 1000–2000 mW | 30–50 mJ | 500–1000 mW |
| Mechanism | Selective destruction of pigmented trabecular meshwork cells without thermal or collateral damage | Thermal effects without trabecular meshwork damage in repetitive microsecond pulses followed by intermittent rest period | Near-infrared energy with deeper penetration into the juxtacanalicular meshwork and the inner wall of Schlemm's canal | Sequence of pattern laser spots on the trabecular meshwork without overlapping, much shorter pulse durations with more spots for the same area to reduce thermal injury diffusion distance |
| Recommended number of applications | 50 or 100 confluent spots | 60–100 spots or confluent spots | 50 adjacent, non-overlapping laser spots | 8 or 16 segments |
| Recommended extent of trabecular meshwork treatment | 180° or 360° of trabecular meshwork | 180° or 360° of trabecular meshwork | 180° of trabecular meshwork | 180° or 360° of trabecular meshwork |
| Expected endpoint | Small bubbles | No visible tissue reaction | Mini-bubble or burst of pigments | No visible tissue reaction after energy titration |
| Repeatable | Yes | Yes | Yes (theoretically) | Unknown |
| Common complications | IOP spikes and anterior uveitis | Burning or heat sensation. IOP spikes and anterior uveitis are uncommon | IOP spikes are possible | Transient IOP spikes are possible |
IOP, intraocular pressure; MLT, micropulse laser trabeculoplasty; PLT, pattern scanning trabeculoplasty; SLT, selective laser trabeculoplasty; TSLT, titanium-sapphire laser trabeculoplasty.