Офтальмохирургия (Dec 2015)
OPTIMIZATION OF CONTACT TRANSSCLERAL DIODE LASER CYCLOPHOTOCOAGULATION TECHNIQUE IN PATIENTS WITH TERMINAL GLAUCOMA ON THE BASIS OF ULTRASOUND BIOMYCROSCOPY
Abstract
Purpose. Rationales for parameters of laser irradiation in contact transscleral diode laser cyclophotocoagulation (Diode CYC) taking into account ciliary body changes determined by means of ultrasound biomycroscopy (UBM) in patients with terminal glaucoma.Material and methods. There were examined 32 patients aged 58-87 years with terminal glaucoma with pain syndrome. The contact diode CYC with different laser energy has been performed. The group 1 (14 eyes) with a «maximum energy dose» included 16 applications of laser energy in 4 segments of a 270° circumference, at a 1.2-1.5mm distance from the limbus, a 1800 mW of power, a 3-second exposition and a 5.4 J pulse (86.4 J of total energy). The group 2 (18 eyes) with a «medium energy dose»: 6 applications of laser energy in 2 segments of 180° circumference, a 1200 mW of power, a 3-second exposition and a 3.6 J pulse (43.2 J of total energy). Usual clinical methods: tonometry, ultrasonic B-scanning, biomicroscopy, ophtalmoscopy, gonioscopy were added with the UBM, that was perfomed before the operation and in postoperative follow up: 3, 14, 28 days, 3 and 6 months.Results. Obtained data was in the basis of differential choice of contact Diode CYC parameters. In case of pronounced ciliary body atrophy which thickness was less than the averaged calculated (less 0.54mm), a more delicate parameters of summary laser energy (group 2) was used. The reduction of ciliary body thickness 6 months later averaged 0.15mm (0.09-0.25mm) (Table 2) and in no cases reached a critical level (0.3mm). In cases of relative maintenance of ciliary body (more than 0.54 mm) the parameters of laser energy were more intensive (the first group). The contact Diode CYC was stopped decreased the intraocular pressure (IOP) by the average of 9.78±4.3mmHg 6 months later. The pain syndrome was stopped. However, even in absence of its complete normalization IOP. Complications took place in 5 cases only of maximum parameters of laser energy: hyphaema (2 cases), uveitis (3 cases) and 1 case of cyliochoroidal detachment.Conclusion. A differential approach in choice of laser parameters for a contact Diode CYC taking into account the presence and degree of the ciliary body atrophy allowed to minimize complications, to remove the pain syndrome and to decrease opthalmotonus.
