Andrew G. Iwach

ANALYSIS OF SURGICAL AND MEDICAL MANAGEMENT OF GLAUCOMA IN STURGE-WEBER SYNDROME

Management of glaucoma associated with Sturge-Weber syndrome (SWS) is difficult. The authors reviewed 36 eyes of 30 SWS patients with either early or late-onset glaucoma with a mean follow-up of 122 months (range, 24-253 months). Intervals between required surgical or medical interventions were analyzed. Intervention was attributed to elevated intraocular pressure (IOP) in 55% of cases and disc change in 45%. Median stable postoperative interval with goniotomy was 12 months; with trabeculotomy, 21 months; with trabeculectomy, 34 months; with argon laser trabeculoplasty, 25 months; and with medications, 57 months. Survival analysis shows statistically significant differences between goniotomy and medications. Intraoperative choroidal expansions developed in 24% of cases receiving a trabeculectomy, and none developed with either goniotomy or trabeculotomy.

Intraocular Pressure Reduction in Normal-tension Glaucoma Patients

BACKGROUND In a collaborative study, patients with untreated normal-tension glaucoma were randomly assigned to a marked intraocular pressure reduction group or to a no therapy group. It was anticipated that medical therapy and laser trabeculoplasty would generally not achieve adequate pressure lowering and that fistulizing surgery would be required. This hypothesis was examined using current observations in the study. METHODS Patients randomized to the therapy group had a pressure reduction of at least 30% from their last prerandomization level. This was achieved within 6 months by means of fistulizing surgery or with pilocarpine and/or laser trabeculoplasty. Beta-blockers and adrenergic agonists were excluded from both eyes. RESULTS Of 30 patients with documented stable 30% pressure reduction, 17 (57%) achieved this with topical medication and/or laser trabeculoplasty: 8 with pilocarpine alone, 2 with laser trabeculoplasty alone, and 7 with laser trabeculoplasty after initial topical medication. The remaining 13 (43%) patients required a single fistulizing procedure. There was no statistically significant difference between the mean follow-up time for the nonfistulized group (533.8 +/- 437.6 days) and for the fistulized group (502.7 +/- 344.7 days). Both treatment groups had similar baseline profiles. CONCLUSION Marked pressure reduction can be achieved and maintained on a long-term basis by means other than fistulizing surgery in a large proportion of patients with untreated normal-tension glaucoma.

Transconjunctival mitomycin-C in needle revisions of failing filtering blebs

PURPOSE To report the efficacy and safety of transconjunctival mitomycin-C as an adjunct to needle revision of failing filtering blebs. DESIGN Retrospective, consecutive, noncomparative interventional case series. PARTICIPANTS Forty-one patients (42 eyes) undergoing bleb revisions by a single surgeon at a single institution from May 1997 to January 2001. METHODS The authors retrospectively reviewed charts of 42 eyes that underwent needle revision of the failing filtering bleb using transconjunctival application of mitomycin-C. Needling of the bleb was performed with a 25-gauge needle. The site of the needle puncture was sutured and followed by application of transconjunctival mitomycin-C (0.5 mg/ml) by means of a sponge left in contact with the conjunctival epithelium for 6 minutes. A group of patients received additional subconjunctival injections of 5-fluorouracil in the postoperative period. Success was defined as a reduction in intraocular pressure of 30% without the use of antiglaucoma medications and no further surgical procedures to control intraocular pressure. MAIN OUTCOME MEASURES Intraocular pressure, visual acuity, complications, number of glaucoma medications used at the final visit. RESULTS Mean preoperative intraocular pressure was 22.1 +/- 8.0 mmHg, which was reduced by 9.6 +/- 7.9 mmHg to a mean postoperative intraocular pressure of 12.5 +/- 6.1 mmHg. Mean follow-up was 17.6 +/- 13.5 months. Kaplan-Meier survival analysis showed a probability of continued success at 12 months of 76.1%, and at 24 months of 71.6%. The most common complication was hyphema in 7.1% of patients. Twenty-six eyes also received postoperative injections of 5-fluorouracil. CONCLUSIONS Transconjunctival mitomycin-C may enhance success of the needling procedure in failing filtering blebs.

Trabeculectomy with Intraoperative Sponge 5-Fluorouracil

PURPOSE To retrospectively assess the outcome of trabeculectomy surgery performed using intraoperative sponge 5-fluorouracil (5-FU) (50 mg/ml). METHODS Trabeculectomy with intraoperative sponge 5-FU was performed on 140 eyes of 119 patients. The reduction in intraocular pressure (IOP), the number of supplementary postoperative injections, and any treatment complications were noted. RESULTS The mean preoperative IOP was 25.7 +/- 8.6 mmHg. The mean postoperative IOP was 12.5 +/- 5.7 mmHg with a mean IOP reduction of 52 percent (P < 0.0001). One hundred twenty-one (86.4 percent) eyes required no postoperative glaucoma medications, with the mean number of glaucoma medications dropping from 2.5 +/- 1.1 before operation to 0.3 +/- 0.8 after operation (P < 0.001). One hundred five eyes received a mean of 5.3 +/- 2.7 postoperative 5-FU injections. There was no significant difference in final IOP or success rate between low- and high-risk eyes, but high-risk eyes seemed to require supplementary postoperative 5-FU. Corneal epithelial damage arose in 52 (37 percent) eyes and correlated strongly with postoperative 5-FU supplementation. CONCLUSION Intraoperative sponge 5-FU is a reasonably safe and effective adjunct to trabeculectomy surgery.

Subconjunctival THC:YAG Laser Thermal Scierostomy

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 microsec), compact, self-contained, solid state laser operating in the near infrared (2.1 mu). A 1-mm conjunctival stab incision was made 12 mm away from the sclerostomy site to allow entry of a specially designed 22-gauge (712 mu) 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 conjunctival trauma.

Long-term results of noncontact transscleral neodymium:YAG cyclophotocoagulation.

PURPOSE To determine the long-term efficacy of noncontact transscleral neodymium:YAG (Nd: YAG) cyclophotocoagulation. METHODS A retrospective analysis was made of 167 patients (173 eyes) with intractable glaucoma treated with noncontact Nd:YAG cyclophotocoagulation between December 1987 and November 1993, reviewing the treatment parameters, complications, and pre- and posttreatment intraocular pressure (IOP). The IOP was compared using a Students t test, and the results were subjected to a Kaplan-Meier life-table analysis. Success was defined as an IOP of 22 mmHg or lower in the absence of phthisis and without having undergone any additional surgical procedures. RESULTS Mean follow-up was 30.5 +/- 22.8 months. Mean preoperative IOP was 40.0 +/- 12.9 mmHg. Mean postoperative IOP was 19.8 +/- 11.4 mmHg (P < 0.05). The mean number of treatment sessions was 1.8 +/- 1.3 (range, 1-8) with 95 eyes (55%) having only one treatment. Kaplan-Meier survival analysis showed a probability of continued success at 3 years of approximately 73% and at 5 years of 45%. Complications included loss of two or more lines of Snellen visual acuity or one or more categories in the low-vision range (40%), phthisis (6.9%), epithelial defects (1.9%), and hyphema (0.6%). CONCLUSION This study suggests that Nd:YAG transscleral cyclophotocoagulation provides a useful long-term reduction of IOP in eyes with advanced or complicated glaucoma, but there is a significant risk of visual loss associated with the procedure.

Clinical Experience of Trabeculotomy for the Surgical Treatment of Aniridic Glaucoma

OBJECTIVE The purpose of this study is to determine the efficacy of initial trabeculotomy in the patient with aniridic glaucoma. DESIGN Clinical charts were reviewed. PARTICIPANTS Twenty-nine eyes of 16 patients with aniridia were studied. INTERVENTION Glaucoma surgery was performed. As an initial procedure, trabeculotomy was performed in 12 eyes, other surgery was performed in 17 eyes (trabeculectomy, 5; goniotomy, 5; other, 7). MAIN OUTCOME MEASURES Success was defined as an intraocular pressure (IOP) of 21 mmHg or lower, and no further surgery was performed. RESULTS Ten (83%) of 12 eyes obtained IOP control after first (6 eyes) or second (4 eyes) trabeculotomy with a mean follow-up period of 9.5 years. Five eyes maintained visual acuity of 20/40 to 20/200. No serious complications were found after trabeculotomy. Three (18%) of 17 eyes were controlled with the first glaucoma surgery other than trabeculotomy (goniotomy, trabeculectomy, trabeculectomy combined with trabeculotomy, and Molteno implant). Good IOP control was obtained in 8 (47%) of 17 eyes after several surgeries with a mean follow-up period of 10.4 years. Four of 17 eyes became phthisical. CONCLUSION This study suggests that trabeculotomy is the preferred initial operation for uncontrolled glaucoma with aniridia.

Endoscopic diode laser cyclophotocoagulation with a limbal approach

BACKGROUND AND OBJECTIVE Endoscopic diode laser cyclophotocoagulation with a limbal approach was reviewed retrospectively. The delivery system and procedure used as well as the role of this procedure in the management of glaucoma are discussed. PATIENTS AND METHODS An 810-nm pulsed continuous-wave diode laser capable of 1.2-W output was used. The maximum treatment area is 7 to 8 clock hours with a single limbal incision. Generally, 800 mW were used for less than 1 second, for a total of 0.8 J per treatment. RESULTS Eight eyes of 6 patients were treated. The mean follow-up time for each procedure was 3.2 months (range 1 to 8 months) and for each eye was 5.1 months (range 2 to 8 months). Pre- and postoperative intraocular pressures were determined. Postoperative inflammation was the most common complication. CONCLUSION One reason for the failure of transscleral cyclophotocoagulation, particularly in congenital glaucoma, may be displacement of the ciliary processes. This displacement does not permit the indirect treatment to reach the appropriate area. Because endoscopic laser cyclophotocoagulation allows direct visualization, treatment can be accurately applied to individual ciliary processes.

Subconjunctival THC: YAG Laser Limbal Sclerostomy Ab Externo in the Rabbit

A chromium-sensitized, and thulium and holmium-doped YAG laser (THC:YAG laser) was used to create bilateral limbal sclerostomies in six Dutch pigmented rabbits. The laser is a long-pulsed (300 microseconds) [corrected], compact, self-contained, solid-state laser operating in the near infrared (2.1 microns). A 1-mm conjunctival stab incision was made 12 mm away from the sclerostomy site to allow entry of a specially designed 26-gauge (480 microns) optic probe that delivers energy at right angles to the long axis of the fiber. Probe insertion minimally disturbed the conjunctiva. Pulse energies of 60 to 150 mJ were used with a repetition rate of 5 pulses/s. Energy levels ranging from 1.35 to 6.6 J produced full-thickness sclerostomies. Histopathology showed a sharply defined perforating limbal wound at all energy levels. The overlying conjunctiva was intact, with swelling of the adjacent cornea. A peripheral iridectomy was intentionally created with the laser through the peripheral limbus, resulting in a sharply defined perforating tract through the iris/ciliary body. This technique may simplify filtering sclerostomy surgery, without anterior chamber instrumentation and with minimal conjunctival trauma.

Long-term results of noncontact neodymium:yttrium–aluminum–garnet cyclophotocoagulation in neovascular glaucoma

PURPOSE To determine the long-term efficacy and safety of noncontact transscleral neodymium:yttrium-aluminum-garnet (Nd:YAG) cyclophotocoagulation (CP) for the treatment of neovascular glaucoma (NVG). DESIGN Retrospective, noncomparative, interventional case series. PARTICIPANTS One hundred fifteen eyes of 111 subjects treated from December 1987 to January 2001. METHODS Eyes with uncontrolled NVG underwent noncontact Nd:YAG CP. Treatment parameters and pretreatment and posttreatment intraocular pressures (IOP) were reviewed. Preoperative and postoperative IOP were compared using a paired Students t test. Success was defined as an IOP </=22 mmHg, with or without medications, in the absence of phthisis bulbi, and without having undergone further surgical procedures. Results were subjected to a Kaplan-Meier life-table analysis. RESULTS Mean follow-up was 27.0 +/- 34.3 months (range, 1-148 months). Mean preoperative IOP was 47.4 +/- 11.1 mmHg (range, 26-70 mmHg). Mean postoperative IOP was 18.3 +/- 12.2 mmHg (range, 0-44 mmHg). The mean number of treatment sessions was 1.4 +/- 0.7 (range, 1-6), with 82 eyes (71.3%) having only one treatment. Kaplan-Meier survival analysis showed a probability of continued success at 1 year of 65.0%, at 3 years of 49.8%, and at 6 years of 34.8%. Phthisis developed in 8.6% of the eyes. CONCLUSIONS Noncontact Nd:YAG CP provides long-term IOP reduction in eyes with medically uncontrolled NVG. This can be associated with complications that include inflammation, visual loss, and hypotony. Repeat treatment may be necessary.