[The laser correction of recurrent elevated intraocular pressure after a surgical operation to control glaucoma complicated by the blocking of the postoperative fistula by the root of the iris]. / Lazernaia korrektsiia retsidiva povysheniia vnurtriglaznogo davleniia posle antiglaukomatoznoi khirurgicheskoi operatsii, oslozhnennoi blokadoi posleoperatsionnoi fistuly kornem raduzhki.

Laser intervention was carried out in 18 patients (18 eyes) with open-angle glaucoma and decompensated intraocular pressure, that developed in 2 weeks--5 years after primary antiglaucoma surgery. Developed glaucoma stage was diagnosed in 16 eyes, in 2 eyes far-advanced condition was found. Blocking of the fistula by the iridal root was responsible for the inefficacy of fistulizing surgery. Laser trabeculoplasty to compensate for the intraocular pressure was carried out in 18 eyes, in 9 eyes this treatment was combined with gonioplasty. Stable normalization of intraocular pressure was observed in 13 eyes in remote periods after laser coagulation. Analysis of the results has brought the authors to a conclusion that the administered laser trabeculoplasty as an individual treatment modality and in combination with gonioplasty is fairly effective, results in prolonged compensation of the ophthalmic tone, and is altogether less traumatic than repeated surgery.

[Histological characteristics of ocular structures after YAG-laser exposure of various sections of the crystalline lens in experimental studies]. / Gistologicheskaia kharakteristika struktur glaza posle IAG-lazernogo vozdeistviia na razlichnye otdely khrustalika v éksperimente.

This work was aimed at analysis of all the aspects, pathomorphologic included, of short-pulsed YAG laser exposure of the lens. Experiments were carried out with 79 rabbit eyes. After laser exposure the eyes were enucleated in 1-24 h and in 7-10 days. Thirty-one eyes were subjected to YAG laser ++capsule puncture. Fragmentation of intracapsular structures was carried out in 23 eyes. Combined operations were performed on 25 eyes. Every series comprised two groups, differing by the energy of laser exposure: 3-5 mJ. Histologic analysis has lead the authors to the following conclusions. The pattern and severity of pathomorphologic changes were directly related to the energy and time of laser exposure and site of the focal plane of irradiation. The major destructive shifts after YAG laser fragmentation of the cortical layer and capsulotomy are focussed at the site of exposure and involve the adjacent sections of the lens. Laser exposure of 3-5 mJ may be used to open the anterior capsule of the lens and to facilitate the cataract mass discharge in extracapsular cataract extraction. Use of combined method helps enhance induration and fragmentation of the cortical layers of the lens, rules out surgical discission of the anterior capsule of the lens, and facilitates removal of the nucleus and wash out of the lens mass.

[Laser correction of recurrence of increased intraocular pressure after surgical valvular sinuso-trabeculectomy]. / Lazernaia korrektsiia retsidiva povysheniia vnutriglaznogo davleniia posle khirurgicheskoi klapannoi sinusotrabekuléktomii.

Wise's laser trabeculoplasty with a 270 degrees exposure was used in 22 eyes of 22 patients with operated-on decompensated glaucoma. Patients with elevated decompensated intraocular pressure after sinusotrabeculoctomy were included in this group. The postoperative fistula was located in front of the Schlemm's canal in them. A dynamic follow-up has shown a stable normalization of the ophthalmic tone in 62% of cases without maintenance therapy. As a repeated intervention, laser trabeculoplasty is less traumatic, yields a good therapeutic effect, and may be widely used as a method to correct elevated intraocular pressure after earlier sinusotrabeculectomy.

Clinical, structural and molecular phototherapy effects of laser irradiation on the trabecular meshwork of human glaucomatous eyes.

The effects of argon laser trabeculoplasty (LTP) on intraocular pressure (IOP), outflow facility, the morphology of the trabecular meshwork (TM), and the pattern of extracellular glycoprotein fibronectin in trabeculum were studied in 46 eyes of patients with primary open-angle glaucoma (POAG). The LTP was done with informed consent, anticipating that trabeculectomy would be carried out at a scheduled time (2 h to several months following laser therapy). We found that the magnitude of IOP reduction and the improvement in the facility of outflow achieved are directly dependent on the time course after LTP and laser-induced structural changes in trabecular tissue. Light microscopic and immunohistochemical evaluations of the TM specimens at earlier intervals after LTP revealed evidence of heat effects, with disruption and shrinkage of the TM collagenous components and accumulation of fibronectin deposits in the aqueous drainage channels as compared with the TMs of matched patients with POAG who did not receive laser treatment. Within 24 h after LTP, proteins of glaucomatous TMs excised from patients incorporated increased amounts of [3H]-leucine radioactive label; however, the amount of [3H]-leucine-labeled material was significantly depressed in later periods of evaluation. The specimens obtained at longer intervals after LTP showed partial or total occlusion of the intertrabecular spaces by extracellular debris; however, the amount of trabecular fibronectin was not significantly different from that measured 24 h after LTP. At least two potential mechanisms are proposed for the TM tissue response to laser treatment, including heat-induced stretching of the collagen in lamellae and fibronectin-mediated attachment of beams supporting an adhesive tightening of the trabecular components caused by LTP. The changes in laser-induced tissue responses appear to be the result of morphological repair of irradiation-injured trabecular tissue.