Postoperative complications of subconjunctival THC-YAG (Holmium) laser sclerostomy

The THC-YAG (Holmium) laser is currently being used to create thermal sclerostomies, an alternate method of intraocular pressure control with poorly regulated glaucoma. A significant advantage of this procedure is the ab externo approach, which utilizes a small fiberoptic laser probe that is advanced subconjunctivally to the limbus. Surgical intraocular trauma is minimized, decreasing the amount of scarring and ultimate bleb failure. Complications may be seen with the THC-YAG sclerostomy and include: conjunctival burn, filtration bleb leak, posterior corneal striae, peaked pupil, iris incarceration, infection, hyphema, cataracts and ocular hypotony.

This paper presents four glaucoma patients, co-managed at the Illinois Eye Institute, who developed complications following THC-YAG laser sclerostomy. A discussion of other possible postoperative complications and their management is included.

While the holmium laser has shown positive results in lowering intraocular pressure in patients with uncontrolled refractory glaucoma, complications are inherent in this procedure. The most common are posterior corneal striae, iris incarceration with secondary peaked pupil, and ocular hypotony. Conjunctival burn with secondary filtration bleb leak, limbal pigment deposition and hyphema may also be seen.

Early diagnosis and treatment of postoperative complications may help in maintaining the long term filtration ability of the sclerostomy.