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* BACKGROUND AND OBJECTIVE: This is a follow-up report on 103 THG:YAG (holmium) sclerostomies ab externo performed on 87 eyes of 81 patients. * PATIENTS AND METHODS: The patients received pulse energies of 0.06 to 0.13 J (mean total energy 4.4 ± 3.3 J, range 0.6 to 17.1 J). * RESULTS: The estimated success rates with or without medication, and allowing a second procedure, were 44% at 2 years and 36% at 4 years. The mean preoperative intraocular pressure (IOP) was 29.7 ± 11.4 mm Hg, and the mean postoperative IOP in the successful patients was 13.6 ± 4.6 mm Hg (P < .01). Hypotony and iris incarceration were the most frequent early complications. * CONCLUSIONS: Although holmium laser sclerostomy is a relatively straightforward procedure and offers some advantages over standard trabeculectomy in select cases, it currently has a number of drawbacks that limit its use. [Ophthalmic Surg Lasers 1996;27:823-831.]

CASE REPORT A 73-year-old Hispanic woman with Type II diabetes mellitus for the past 3 years is referred for management of ocular hypertension. Her family history is unremarkable. Slitlamp biomicroscopy reveals no apparent secondary cause for her elevated intraocular pressure (IOP) and both angles are widely open with mild, uniform, trabecular pigmentation. Cup–disc ratios are 0.6 OU, with pink, healthy neural rims without evidence of thinning, notch, nerve fiber layer defect, or localized pallor. Achromatic automated perimetry is unremarkable, and short-wavelength perimetry is unreliable. IOPs range from 23 to 28 mm Hg. Corneal thicknesses are 558 and 560 μm, in the right and left eyes, respectively. 1. Which patients with ocular hypertension should be treated? 2. Should one correct IOP for corneal thickness and if so, how should this be done? 3. How should IOP be measured in eyes with irregular corneal surfaces or following keratorefractive surgery?

Background: Laser sclerostomy can be performed in a less-invasive manner than standard filtering surgery. Longer wavelengths in the infrared range have water-absorptive characteristics that facilitate perforation of the sclera. The goal was to perform laser sclerostomy ab externo to avoid intraocular instrumentation and minimize conjunctival trauma. Methods: A thulium, holmium, chromium-doped:YAG (THC:YAG) crystal laser was used to create thermal sclerostomies in 49 glaucomatous eyes of 46 patients. The laser is a long-pulsed (300-μsecond), compact, self-contained, solid-state laser operating in the near infrared (2.1 μm). Energy was delivered via a specially designed 22-gauge (712-μm) optic probe that emits energy at a right angle to the long axis of the fiber. Pulse energies of 80 to 120 mJ were used. Total energy levels to produce full-thickness sclerostomies ranged from 1.4 to 7.2 J. Subconjunctival 5-fluorouracil (5-FU) injections were administered in 46 eyes. Success was defined as an intraocular pressure (IOP) of less than or equal to 22 mmHg with or without medications. For eyes in which preoperative IOP was less than or equal to 22 mmHg, success was defined as a decrease in IOP of greater than or equal to 30%. Results: Estimated probability of success allowing for one retreatment was 0.75 at 6 months and 0.68 at 12 months. Mean IOP of successful cases was 13.3 mmHg at both 6 and 12 months. Twelve cases failed within the initial 6 months, and two additional cases failed by 12 months. Conclusion: THC:YAG ("holmium") laser thermal sclerostomy is an alternative to other full-thickness filtration procedures. Further evaluation and understanding will define its ultimate role in glaucoma management.

A THC:YAG laser (thulium, holmium, chromium-doped YAG crystal) was used to create thermal sclerostomies in 21 glaucomatous eyes of 19 patients. The laser is a long-pulsed (300 µsec), compact, self-contained, solid state laser operating in the near infrared (2.1 µ). A 1-mm conjunctiva) stab incision was made 12 mm away from the sclerostomy site to allow entry of a specially designed 22-gauge (712 µ) optic probe that delivers energy at a right angle to the long axis of the fiber. Probe insertion produced minimal disturbance of the conjunctiva. Pulse energies of 80 mJ to 120 mJ were used with a repetition rate of 5 pulses/second. Total energy levels to produce full-thickness sclerostomies ranged from 1.4 to 4.8 J. Subconjunctival 5-fluorouracil injections were administered in 15 eyes. At 3 months the mean intraocular pressure of successful cases (16) was 14 mmHg (range, 9 to 22 mmHg). Of successful cases, the mean intraocular pressure at 6 months was 13 mmHg (range, 2 to 22 mmHg). Five cases failed within the initial 3 months, and 3 additional cases failed by 6 months. The authors conclude that this full-thickness sclerostomy technique may simplify filtering surgery without anterior chamber instrumentation and with minimal conjunctiva) trauma.

To evaluate whether baseline visual field data and asymmetries between eyes predict the onset of primary open-angle glaucoma (POAG) in Ocular Hypertension Treatment Study (OHTS) participants.A new index, mean prognosis (MP), was designed for optimal combination of visual field thresholds, to discriminate between eyes that developed POAG from eyes that did not. Baseline intraocular pressure (IOP) in fellow eyes was used to construct measures of IOP asymmetry. Age-adjusted baseline thresholds were used to develop indicators of visual field asymmetry and summary measures of visual field defects. Marginal multivariate failure time models were constructed that relate the new index MP, IOP asymmetry, and visual field asymmetry to POAG onset for OHTS participants.The marginal multivariate failure time analysis showed that the MP index is significantly related to POAG onset (P0.0001) and appears to be a more highly significant predictor of POAG onset than either mean deviation (MD; P = 0.17) or pattern standard deviation (PSD; P = 0.046). A 1-mm Hg increase in IOP asymmetry between fellow eyes is associated with a 17% increase in risk for development of POAG. When threshold asymmetry between eyes existed, the eye with lower thresholds was at a 37% greater risk of development of POAG, and this feature was more predictive of POAG onset than the visual field index MD, though not as strong a predictor as PSD.The MP index, IOP asymmetry, and binocular test point asymmetry can assist in clinical evaluation of eyes at risk of development of POAG.

Background The prevalence of glaucoma is higher in African American individualsthan in white individuals. Objective To report the safety and efficacy of topical ocular hypotensive medicationin delaying or preventing the onset of primary open-angle glaucoma (POAG)among African American participants in the Ocular Hypertension Treatment Study. Methods Eligibility criteria included age between 40 and 80 years, intraocularpressure between 24 and 32 mm Hg in one eye and between 21 and 32 mm Hg inthe other eye, and no evidence of glaucomatous structural or functional damageby standard clinical measures. Participants were randomized to either theobservation group or medication group. Of the 1636 participants randomized,408 were self-identified as African American. Main Outcome Measure The primary outcome was the development of reproducible visual fieldabnormality and/or reproducible optic disc deterioration attributed to POAG. Results Among African American participants, 17 (8.4%) of 203 in the medicationgroup developed POAG during the study (median follow-up, 78 months) comparedwith 33 (16.1%) of 205 participants in the observation group (hazard ratio,0.50; 95% confidence interval, 0.28-0.90; P = .02). Conclusion Topical ocular hypotensive therapy is effective in delaying or preventingthe onset of POAG in African American individuals who have ocular hypertension.

• We examined the influence of topically administered flurbiprofen sodium 0.03%, a potent prostaglandin inhibitor, on the inflammatory response and intraocular pressure following argon laser trabeculoplasty. Our investigation included one eye of each of 118 patients with primary open-angle glaucoma in whom laser trabeculoplasty was indicated. Sixty-three patients received flurbiprofen and 55 received a vehicle during the two-hour period immediately preceding laser therapy and for one week postoperatively. No significant differences in postoperative IOPs were noted between groups. However, when we considered conjunctival erythema at 24 hours or control of inflammation at the termination of the investigation, the eyes receiving flurbiprofen had less inflammation than did the vehicle-treated eyes.

During the past several years the Neodymium:YAG laser has become increasingly popular for performing peripheral iridotomy. Using energy levels of 2-8 millijoules per shot and 1-3 shots per treatment, most irides can be penetrated in one sitting. Nd:YAG laser iridotomies show very little tendency to close, except in patients with active intraocular inflammation. A small amount of hemorrhage is common following YAG laser iridotomy, but clinically significant hyphema is rare. Significant lenticular or corneal damage is extremely rare. Although longterm follow-up of large numbers of patients is lacking, Nd:YAG laser iridotomy appears to be a safe and effective alternative to Argon laser iridotomy in selected patients.