Procedure has ability to lower IOP, preserve vision similar to trabeculectomy and tube shunts
Blebless ab externo glaucoma surgeries, which include canaloplasty and deep sclerectomy, are successful at lowering high IOP while still maintaining a good safety profile. Filtering surgeries, such as trabeculectomy, ExPRESS shunt (Alcon Laboratories, Fort Worth, Texas, USA), and tubes, are the go-to options when a patient requires an IOP lower than 10 to 12 mmHg.
Transscleral cyclophotocoagulation (TSCPC) has typically been reserved for patients with little hope of maintaining their vision. The American Academy of Ophthalmology Ophthalmic Technology Assessment Committee stated, "Cyclophotocoagulation is indicated for patients with refractory glaucoma who have failed trabeculectomy or tube shunt procedures, patients with minimal useful vision and elevated IOP, patients who have no visual potential and need pain relief, and patients with complicated glaucoma and conjunctival scarring from previous surgery."1
New techniques, such as the slow coagulation method by Doug Gaasterland, are making TSCPC safer. This approach uses a lower amount of energy over a longer duration of time, leaving the eyes quieter, and it reduces some of the complications, such as inflammation, uveitis and cystoid macular oedema.
On the cusp of development is a MicroPulse CPC procedure, which is believed will further enhance safety and allow more comfort in using the procedure earlier in the treatment paradigm. In addition, the use of steroids and non-steroidal anti-inflammatory drugs perioperatively has helped mitigate some of the complications.
A glaucoma device (G-Probe, Iridex, Mountain View, California, USA) is designed to direct infrared energy toward the ciliary body and I tend to err on the side of posterior placement as well. In highly myopic eyes, I often use transillumination to identify the exact location of the ciliary body. This technique is effective anytime extra confidence is needed with where to direct the laser and more precise targeting of the ciliary processes can reduce pain and inflammation after the procedure.