The Effectiveness of Selective Laser Trabeculoplasty in Patients with Medically Uncontrolled Open-angle Glaucoma

PURPOSE: To determine the effect of intraocular pressure (IOP) reduction of selective laser trabeculoplasty (SLT) on medically uncontrolled open-angle glaucoma (OAG) and the factors associated with the treatment result. METHODS: Forty-seven eyes of 47 OAG patients were enrolled for 180° SLT or 360° SLT, all under maximal tolerated medical therapy and with IOP above their target pressure. All patients were followed-up for at least 1 year after the procedure. Treatment success was defined as IOP reduction ≥20% from baseline at 12 months after SLT treatment without additional anti-glaucomatous intervention. RESULTS: The treatment success rate was 65.96%. Baseline IOP was 23.84 ± 4.52 mmHg in the success group and 21.44 ± 2.97 mmHg in the failure group (p = 0.035). Significant mean IOP reduction was observed at 6, 9, and 12 month follow-ups (p = 0.001 at 6 months; 0.041 at 9 months, and <0.001 at 12 months). The success rate did not vary significantly by sex (p = 0.362), age (p = 0.081), history of cataract surgery (p = 0.470), number of medications (p = 0.857), duration of medication (p = 0.613), or angular degree of SLT treatment (180° vs. 360°) (p = 0.137). There was a positive correlation between mean baseline IOP and mean reduction of IOP from baseline in the success group (p < 0.001, r = 0.861), while there was no such correlation in the failure group (p = 0.272, r = −2.921). CONCLUSIONS: SLT was an effective treatment for IOP reduction until 12 months in medically uncontrolled OAG patients. A greater amount of IOP reduction is expected in patients with higher baseline IOP in the success group.

An Experimental Study of Noncontact Transscleral Diode Laser Cyclophotocoagulation in Rabbits

Acute and long-term effects of the noncontact transscleral diode laser cyclophotocoagulation were studied in 6 pigmented rabbits used laser power level was 0.15J, 0.25J, 0.5J and 0.75J. Each eyeballs was enuleated 1.7 and 21 days after cyclophotocoagulation for histopathologic examination. The findings with diode laser were coagulation necrosis of pigmented epitihelium, nonpigmented epitihelium and stroma, congestion of vessel, pigment dispersion and detachment of pigment epithelium. Twenty one days after laser treatment, the light microscopic examination revealed atrophy of nonpigmented epithelium and pigmented epithelium, fibrosls, pigment laden macrophages. These changes were obvious in rabbits treated with a power more than 0.5J. It is suggested that noncontact trasnscleral cyclophotocoagulation with diode laser is useful in lowering intraocular pressure.