Apraclonidine and argon laser trabeculoplasty.

Sixty patients with medically uncontrolled open-angle glaucoma (intraocular pressure greater than 21 mm Hg) were randomly assigned to one of two treatment regimens with apraclonidine before undergoing 360-degree argon laser trabeculoplasty. One drop of apraclonidine 1% was instilled one hour before and immediately after laser treatment in 30 eyes or apraclonidine was delivered only after trabeculoplasty in 30 eyes. Intraocular pressure before laser treatment, number of antiglaucoma medications, and the laser treatment settings were comparable between the two groups. The mean and percent change in intraocular pressures were similar in both treatment groups one and two hours after trabeculoplasty. One drop of apraclonidine 1% instilled immediately after argon laser trabeculoplasty prevented intraocular pressure increase one hour and two hours postoperatively as effectively as its instillation both one hour before and immediately after laser treatment.     

Laser trabeculoplasty re-treatment

Because of inadequate control of intraocular pressure, 26 eyes of 24 patients with primary and secondary open-angle glaucoma who had previously undergone argon laser trabeculoplasty were re-treated. Re-treatment was successful in ten eyes (38%); their average decrease in intraocular pressure was 10.2 mm Hg. After laser re-treatment, three eyes (12%) had marked increases in intraocular pressure, ranging from 10 to 37 mm Hg above baseline, necessitating urgent surgical intervention.     

Argon laser trabeculoplasty in primary open-angel glaucoma — results in a black Jamaican population

A controlled, randomised, prospective trial of Argon laser trabeculoplasty (ALT) was carried out on 48 eyes of 30 black Jamaican patients with primary open-angle glaucoma. All eyes had uncontrolled intra-ocular pressures (22mm Hg) despite medical therapy.Treatment was successful in controlling intraocular pressure in 68% of eyes after 12 months follow-up (p = 0.004). The average drop in intraocular pressure attributable to ALT was 6.6 mmHg. Argon laser trabeculoplasty is an effective adjunct in managing to control intraocular pressure in black Jamaican glaucoma patients.     

Bilateral argon laser trabeculoplasty in primary open-angle glaucoma

We performed bilateral argon laser trabeculoplasty on 34 patients with medically uncontrolled open-angle glaucoma. Preoperative intraocular pressure was greater than 21 mm Hg, with a less than 3-mm Hg difference between the two eyes. Laser treatment (360 degrees) was performed on both eyes within a three-month interval. Mean (+/- S. D.) baseline intraocular pressure was similar in the first- (26.9 +/- 3.7 mm Hg) and second- (26.5 +/- 3.3 mm Hg) treated eyes. One hour after treatment, four first- and four second-treated eyes had a greater than 30% increase in intraocular pressure. The one-hour change in pressure was highly correlated between the two eyes (r = .794, P less than .0001). Intraocular pressure was reduced (P less than .0001) one, two, and three years after treatment in both the first and second-treated eyes. The percentages of first- and second-treated eyes with a pressure of less than or equal to 21 mm Hg were similar at one, two, and three years. Pressure response between the two eyes was correlated (P less than .0001) at year 1 (r = .815), 2 (r = .757), and 3 (r = .886) after laser therapy.     

Argon Laser Trabeculoplasty in the Presurgical Glaucoma Patient

The trabecular meshwork in 334 eyes of 260 patients with medically uncontrolled primary and secondary open-angle glaucoma was treated with the argon laser. The average intraocular pressure reduction obtained was 7.1 mm Hg. Tonographic data showed significant increase in the facility of outflow. Glaucoma surgical intervention was avoided in 87.5% of phakic eyes and in 62.1% of aphakic eyes. Laser trabeculoplasty was found to be effective in primary open-angle glaucoma, pseudoexfoliation glaucoma, pigmentary glaucoma, angle recession glaucoma, glaucoma secondary to uveitis, and in eyes with failed glaucoma surgical procedures. The length of follow-up in this series ranged from one week to 21 months, with an average of five months. The major complication noted was a rise in intraocular pressure following treatment. In one eye, a small central island of vision was lost due to this intraocular pressure elevation. Treating one-half of the angle in each of two treatment sessions separated by a few weeks reduces the degree of this pressure elevation. The glaucoma status of 3% eyes was made worse after treatment with trabeculoplasty.     

Comparative study of argon laser trabeculoplasty in primary open-angle and pseudoexfoliation glaucoma

In 93 phakic eyes--52 eyes with primary open-angle and 41 eyes with exfoliation glaucoma--with increased intraocular pressure, argon laser trabeculoplasty was performed. Fifty to sixty burns were made over 180 degrees of the lower trabecular meshwork. During the follow-up period, visual acuity, intraocular pressure, medication changes and the need for surgery were studied. In 25 eyes a second laser treatment was performed over 180 degrees of the upper trabecular meshwork. Intraocular pressure control was obtained in 81% of the eyes with primary open-angel glaucoma and 71% of the eyes with pseudoexfoliation glaucoma. The average reduction of pressure obtained after laser trabeculoplasty was 9.22 mm Hg for the group of eyes with primary open-angle glaucoma and 13.42 mm Hg for the group of eyes with pseudoexfoliation glaucoma (p less than 0.001). Reduction in medical treatment was obtained in 27 eyes from the 71 eyes with successful reduction of the intraocular pressure. In 6 eyes with successful results after argon laser trabeculoplasty, cataract extraction was performed. The intraocular pressure remained normal in all eyes after the operation.     

Two-stage argon laser trabeculoplasty in open-angle glaucoma

Forty-five adults with primary open-angle glaucoma received argon laser trabeculoplasty in two stages (180 degrees in each session) separated by one month. The indication for argon laser trabeculoplasty in each case was uncontrolled glaucoma consisting of progressive optic disk cupping and visual field loss despite maximally tolerable medication. A P value of .01 by Student's two-tailed paired t-test was used for statistical significance in the analysis of the intraocular pressure data. In most cases, the greatest reduction in intraocular pressure followed stage 1. Some patients received no additional benefit from stage 2; in other cases, the second stage was not only beneficial but provided most of the reduction in pressure. The pretreatment intraocular pressure level influenced the response to laser therapy. Patients with the highest pretreatment intraocular pressures received the most benefit. Both stages were complicated by a transient postoperative increase of 5 mm Hg or more in 12 patients (approximately 19%).     

Comparative krypton and argon laser trabeculoplasty

Laser trabeculoplasty was performed to treat medically uncontrolled open-angle glaucoma (glaucoma chronicum simplex). Twenty-five eyes were treated with a red krypton laser, while in 110 eyes the usual blue-green argon laser was used, and in 14 eyes a pure green argon laser, under the same conditions. After treatment with the krypton laser the average drop in intraocular pressure at 24 hours was 4.8 mm Hg; at 4 weeks it was 2.3 mm Hg, and at 3 months there was no longer any appreciable effect. In the cases treated by argon laser the pressure drop was significantly greater and lasting, averaging 7.8-8.2 mm Hg from 24 hours after the treatment onward for at least 12 months. There was no difference between the blue-green and the green argon laser as regards pressure drop and improvement in outflow facility.     

Selective laser trabeculoplasty as initial and adjunctive treatment for open-angle glaucoma

PURPOSE: To investigate the efficacy and safety of selective laser trabeculoplasty as an initial treatment for newly diagnosed open-angle glaucoma, and its role as adjunctive therapy. PATIENTS AND METHODS: A prospective multicenter nonrandomized clinical trial was performed. Patients with newly diagnosed open-angle glaucoma or ocular hypertension were assigned to the primary (selective laser trabeculoplasty) treatment group or the control (latanoprost) group according to patient choice. Both groups were followed up at 1, 3, 6, and 12 months. A secondary treatment group was also included to study the efficacy of selective laser trabeculoplasty for patients intolerant of medical therapy or in whom such therapy was unsuccessful, with or without a history of previous argon laser trabeculoplasty. RESULTS: One hundred eyes (61 patients) were enrolled, 74 in the primary treatment group and 26 in the control group. The average absolute and percent reductions in intraocular pressure for the primary treatment group were 8.3 mm Hg or 31.0%, compared with 7.7 mm Hg or 30.6% for the control group (P = 0.208 and P = 0.879). The responder rates (20% pressure reduction) were 83% and 84% for the primary and control groups, respectively. There were no differences in intraocular pressure lowering with selective laser trabeculoplasty on the basis of angle pigmentation. A modest contralateral effect was observed in the untreated fellow eyes of patients undergoing selective laser trabeculoplasty. CONCLUSIONS: Selective laser trabeculoplasty was found to be equally efficacious as latanoprost in reducing intraocular pressure in newly diagnosed open-angle glaucoma and ocular hypertension over 12 months, independent of angle pigmentation. Nonsteroidal antiinflammatory therapy had similar efficacy to steroids after laser therapy. These findings support the consideration of selective laser trabeculoplasty as a first-line treatment for newly diagnosed open-angle glaucoma or ocular hypertension.     

Long-term follow-up of argon laser trabeculoplasty in uncontrolled primary open-angle glaucoma. A study with standardized extensive preoperative treatment

The long-term results of 180 degrees argon laser trabeculoplasty (ALT) were studied in 61 eyes of 43 patients with uncontrolled primary open-angle glaucoma [intraocular pressure (IOP) less than 22 mm Hg]. In order to enhance the relevance of this prospective study, only eyes that had not responded to medication despite standardized extensive therapy were followed up over an average period of 4.4 years [52.8 +/- 7.3 (mean +/- SD) months]. The success rate of treatment (decrease in IOP less than 5 mm Hg, IOP below 20 mm Hg, stable visual field, stable optic nerve head and no further laser or surgical intervention) after 4.4 years was 73.7%. The mean decrease in IOP was 8.5 +/- 2.9 mm Hg (mean +/- SD). Eyes receiving ALT before cataract surgery retained control of IOP after surgery. A comparable pressure control was also attained with those eyes that had undergone previous trabeculectomy. Failures (26.3%) all occurred in the 1st year after treatment. The results and conclusions from our study are compared with those reported in the literature. The different theories regarding the mechanisms of action of ALT are discussed.     

Efficacy of argon laser trabeculoplasty in primary open-angle and pseudoexfoliative glaucoma: Long-term follow-up

A retrospective study was performed to evaluate the long-term efficacy of argon laser trabeculoplasty in 131 patients (148 eyes) with primary open-angle or pseudoexfoliative glaucoma. Success was defined as an intraocular pressure of 22 mm Hg or less, no further glaucoma surgery, and use of comparable or lower-dose topical antiglaucoma treatment. Efficacy of laser trabeculoplasty decreased with time (follow-up, 6 to 120 months). Good results persisted for about 2.5 years in 50% of cases.     

Three-year efficacy of argon laser trabeculoplasty

The authors report on the effect of argon laser trabeculoplasty on intraocular pressure (IOP) over a 3-year period with a mean follow-up period of 1.8 years in patients with uncontrolled primary open-angle glaucoma who had not undergone prior surgery. An analysis of the effect of laser trabeculoplasty using the criteria for success of an IOP of 22 mmHg or less with no further laser trabeculoplasty or glaucoma surgery, showed a cumulative success of 79% (112 eyes) at 1 year, 69% (85 eyes) at 2 years, and 59% (58 eyes) at 3 years. Similar results are presented for 22 eyes from patients with pseudoexfoliation glaucoma. The authors conclude that although the initial success rate of laser trabeculoplasty is high, it diminishes progressively over time.     

Correlation between intraocular pressure control and progressive glaucomatous damage in primary open-angle glaucoma

Fifty-five patients with primary open-angle glaucoma and early glaucomatous damage who had medical therapy and laser trabeculoplasty were followed up for four to 11 years or until progressive glaucomatous damage was documented. Factors associated with the stability or progression of glaucoma were evaluated. Eyes with mean intraocular pressure higher than 21 mm Hg during the follow-up period uniformly had progressive glaucomatous changes. Conversely, eyes with mean intraocular pressure less than 17 mm Hg remained stable, and approximately half of the eyes with mean intraocular pressure between 17 and 21 mm Hg had progressive glaucomatous changes. Patients who remained stable were slightly younger than those with progressive glaucomatous changes (P less than .05), but initial optic nerve head appearance, initial visual field findings, number of medicines used, medical history, and patient gender or race were not statistically associated with stability or progression of the glaucoma. These findings reinforce the importance of intraocular pressure control in primary open-angle glaucoma and the need to identify other markers that help determine the proper level of intraocular pressure for individual patients.     

Long-term reduction of intraocular pressure after repeat argon laser trabeculoplasty

Thirty-eight eyes (in 31 patients with glaucoma) that had shown a favorable response to an initial argon laser trabeculoplasty had a repeat laser trabeculoplasty four to 81 months (mean +/- S.E.M., 23 +/- 3 months) later because of inadequately controlled intraocular pressures. A mean (+/- S.E.M.) of 65 +/- 3 burns (range, 50 to 115) were given during the initial laser trabeculoplasty, and 58 +/- 2 burns (range, 36 to 100) were given during the first repeat treatment. Three months after the first repeat laser trabeculoplasty, one eye (3%) had undergone filtering surgery and 30 eyes (78%) were considered successes. Of the 30 eyes that were followed up for 12 months after the first repeat laser trabeculoplasty, two (7%) had undergone filtering surgery, three (10%) had received a second repeat laser trabeculoplasty, and 22 (73%) were successes. Fifteen eyes underwent a second repeat laser trabeculoplasty at six to 47 months (mean +/- S.E.M., 21 +/- 3 months) after the first repeat laser trabeculoplasty. Seven (47%) of these eyes required filtering surgery within three to 12 months after the second repeat laser trabeculoplasty. Four of 38 (11%) of the initial, two of 38 (5%) of the first repeat, and zero of 15 of the second repeat laser trabeculoplasty treatments resulted in a one- to two-hour rise in intraocular pressure of at least 10 mm Hg.     

Effects of laser trabeculoplasty on the human aqueous humor dynamics: a fluorophotometric study

Thirteen eyes, seven with primary open-angle glaucoma and six with capsular glaucoma, were treated with laser trabeculoplasty (a fluorophotometric examination was performed about one week prior to it). The intraocular pressure was reduced below 20 mm Hg in eight eyes, and the second fluorophotometric examination could be carried out in six successfully treated eyes about three months later. In the six successfully treated eyes, the pre-laser trabeculoplasty examination showed the following results: IOP: 22 +/- 2 mm Hg; the cornea-aqueous transfer coefficient for fluorescein: 0.32 +/- 0.10 hour-1; and the aqueous flow rate: 1.31 +/- 0.53 microliter min-1. The post-laser trabeculoplasty examination gave the following results: IOP: 15 +/- 2 mm Hg; the cornea-aqueous transfer coefficient: 0.29 +/- 0.08 hour-1; and the aqueous flow rate: 1.23 +/- 0.41 microliter min-1. No significant difference was found in the aqueous flow rate or the cornea-aqueous transfer coefficient before and after.     

Diode laser compared with argon laser for trabeculoplasty

A randomized prospective study on two groups of ten patients compared the efficacy of diode laser and argon laser trabeculoplasty. In the diode laser group the intraocular pressure was 23.0 +/- 3.97 mm Hg before the treatment, 20.2 +/- 4.49 mm Hg at two hours, 16.3 +/- 3.13 at six months, and 16.9 +/- 2.80 mm Hg at one year. The differences from baseline were statistically significant at six months (P = .0001) and at one year (P = .0001) but not at two hours. In the argon laser group the intraocular pressure was 23.4 +/- 3.6 mm Hg before the treatment, 22.7 +/- 4.35 mm Hg at two hours, and 17.6 +/- 4.53 mm Hg at six months. One patient had uncontrolled mean high intraocular pressure and underwent surgery. In the nine patients who completed the study the intraocular pressure at one year was 16.7 +/- 3.00 mm Hg. The differences from baseline were significant at six months (N = 10; P = .0001) and 12 months (N = 9; P = .0001) but not at two hours. Differences between the two groups were not significant at two hours, six months, and one year. Laser trabeculoplasty may be effectively with a diode laser.     

Five-year results of the first 159 consecutive phakic chronic open-angle glaucomas treated by argon laser trabeculoplasty

159 phakic eyes with chronic open-angle glaucoma were treated by argon laser trabeculoplasty and followed for 5 years. According to our criteria of failure, 31 eyes were failures at 1 year (19%), 47 eyes at 2 years (30%), 66 eyes at 3 years (41%), 77 eyes at 4 years (48%) and 82 eyes at 5 years (52%). In the 77 eyes still controlled at 5 years, the intraocular pressure drop was 6.57 mm Hg and the initial medical treatment could be tapered or stopped in only 33 of the cases (43%). In the 82 failures, there was a greater percentage requiring surgery for pressure control during the first year after laser treatment: 16 trabeculectomies in 31 failures (52%). The initial mean intraocular pressures of 7 failures needing surgery during the first 2 months (27.22 mm Hg) and of the 27 failures needing surgery during the 5 year follow-up (24.41 mm Hg) were higher than the initial mean intraocular pressure of the 77 successful cases (22.67 mm Hg). In the 159 eyes followed for 5 years, 19% (31 eyes) to 6% (5 eyes) new failure cases per year were encountered and the initial good results obtained by argon laser trabeculoplasty persisted for about 5 years in half of the cases.     

Variation of techniques on the results of argon laser trabeculoplasty

Patients with uncontrolled open-angle glaucoma were treated with argon laser to the trabecular meshwork. These patients were divided into six groups. Each group of eyes had a slightly different technique of argon laser therapy. Except for one group, there was an adequate pressure lowering effect at the longest follow-up (-18 to -28%). Since the worst complication of argon laser trabeculoplasty is the immediate elevation in intraocular pressure with subsequent worsening of the field and/or disc, the immediate rise in intraocular pressure was measured and compared for each of the various techniques. In addition comparison was made when treating 180 degrees in one eye and 360 degrees in the other eye of 30 individuals having similar glaucomatous disease bilaterally. Little difference was noted between the two eyes.     

Argon laser trabeculoplasty as a means of decreasing intraocular pressure from "normal" levels in glaucomatous eyes

We conducted a retrospective study of 67 patients (85 eyes) with severe glaucoma to determine whether argon laser trabeculoplasty could reduce intraocular pressures below the "normal" range. All patients had initial intraocular pressures of less than or equal to 19 mm Hg. Success was defined as a decrease in intraocular pressure of at least 20%, no increase in medications, stable visual field, and no subsequent glaucoma surgery. After an average follow-up period of 30 months, treatment was successful in 31 cases. One half of the failures occurred by six months and 11 failures (30%) occurred after 12 months. Sixteen patients were able to decrease their medications. Two patients achieved intraocular pressures between 6 and 9 mm Hg and 20 between 10 and 12 mm Hg.     

Results of laser trabeculoplasty performed by residents

Although there have been numerous reports on the results of argon laser trabeculoplasty (ALT) since 1979, few have reported the results of this mode of therapy in an ophthalmology resident clinic population. We retrospectively studied 32 eyes of 25 people with phakic open-angle glaucoma who had received ALT performed by ophthalmology residents at University Hospitals of Cleveland under the supervision of a staff physician. Subgroups based on race, initial (pretreatment) intraocular pressure, and follow-up interval were analyzed. There was a significant difference in mean intraocular pressure from pretreatment to posttreatment for all subgroups, except when the initial intraocular pressure was 36 mm Hg or greater. Argon laser trabeculoplasty performed by residents in a university training program can obtain comparable results with those reported from major glaucoma referral practices.