Otago glaucoma surgery outcome study: long-term follow-up of cases of primary glaucoma with additional risk factors drained by molteno implants

OBJECTIVE: This study was undertaken to provide data on the long-term results of cases of primary open-angle glaucoma with additional risk factors drained by Molteno implants in the province of Otago, New Zealand. DESIGN: Prospective, noncomparative case series PARTICIPANTS: One hundred thirty eyes of 103 patients drained by Molteno implants as the first surgery between 1984 and 1999. INTERVENTION: Insertion of Molteno implant (Ethicon Inc., Johnson & Johnson, Somerville, NJ) using the Vicryl-tie technique. MAIN OUTCOME MEASURES: Intraocular pressure (IOP), visual acuity, visual field. RESULTS: Insertion of a Molteno implant controlled the IOP at 21 mmHg or less with a probability of 1.0 (95% confidence interval [CI], 0.90, 1.0) at up to 7 or more years after surgery. The mean preoperative visual acuity of 20/160 improved to 20/50 after operation and then declined to 20/55 at 5 years and 20/80 after 10 years. The probability of retaining useful vision (visual acuity, >20/400; visual field, >5 degrees radius) was 0.86 (95% CI, 0.77, 0.94) and 0.78 (95% CI, 0.67, 0.89) at 5 and 7 or more years, respectively, after surgery. CONCLUSIONS: The insertion of Molteno implants using the Vicryl-tie technique in this series of 130 cases of primary open-angle glaucoma with additional risk factors controlled the IOP in all cases.     

Otago glaucoma surgery outcome study : long-term results of uveitis with secondary glaucoma drained by Molteno implants

OBJECTIVE: This study was undertaken in Otago, New Zealand, to provide data on the long-term results of cases of uveitis with secondary glaucoma drained by Molteno implants. DESIGN: A prospective, noncomparative case series of all cases of chronic uveitis with secondary glaucoma drained by Molteno implants from 1978 through 1998. PARTICIPANTS: Forty eyes of 35 patients. INTERVENTION: Insertion of Molteno implant. MAIN OUTCOME MEASURES: Intraocular pressure, visual acuity, and progressive visual field loss. RESULTS: Insertion of a Molteno implant was effective in controlling the intraocular pressure at 21 mmHg or less with a probability of 0.87 (95% confidence interval [CI], 0.76, 0.98) and 0.77 (95% CI, 0.60, 0.93) at 5 and 10 or more years after surgery. The mean visual acuity improved from 20/100 to 20/70 immediately after operation. This value declined to 20/130 at 5 and 10 years after surgery and then improved slightly to 20/120 at 15 years after surgery. In these eyes, the Kaplan-Meier estimated probability of retaining useful vision (visual acuity >20/400; visual field >5 degrees radius) was 0.75 (95% CI, 0.61, 0.89) and 0.71 (95% CI, 0.55, 0.87) at 5 and 7 or more years after surgery. CONCLUSIONS: The insertion of a Molteno implant controlled the intraocular pressure in 76% of cases over the follow-up period. Patients in whom the uveitis was well controlled maintained their visual acuity and visual fields, whereas the proportion of cases requiring steroids and the doses required fell progressively over the period of follow-up. Failures were related to complications of advanced disease, previous intraocular surgery, and failure to control the uveitis. The drainage system provided by the Molteno implant proved robust, continuing to function well despite continuous activity of the uveitis, acute exacerbations of the uveitis, and all subsequent intraocular surgery including cataract extraction, keratoplasty, and vitrectomy.     

Long-term results of Molteno implant insertion in cases of chronic angle closure glaucoma

BACKGROUND: This study was undertaken to provide data on the long-term results of cases of chronic angle closure glaucoma with additional risk factors treated by Molteno implants between 1985 and 2004 at Dunedin Hospital, New Zealand. METHODS: A prospective non-comparative case series followed 21 eyes (17 patients) for a mean of 5.7 years (range 1.3-16.3 years) in terms of intraocular pressure, visual acuity and subsequent procedures. RESULTS: Insertion of a Molteno implant has controlled the intraocular pressure at 21 mmHg or less in 100% of cases at 5 years after surgery, the probability of control being 0.95 (95% CI 0.91-0.99). The mean number of hypotensive medications reduced from 2.04 (SD 0.92) preoperatively to 1.40, 0.64 and 0.66 at 1, 2 and 5 years, respectively. The mean visual acuity improved from 6/18 preoperatively to 6/12 at 1 year and declined to 6/13.5 at 2 and 5 years. CONCLUSION: Insertion of Molteno implants was a safe and effective procedure in the management of complex cases of chronic angle closure glaucoma.     

Otago Glaucoma Surgery Outcome Study: long term results of cataract extraction combined with Molteno implant insertion or trabeculectomy in primary glaucoma

BACKGROUND/AIMS: To describe the long term results of cases of cataract extraction combined with either Molteno implant insertion or trabeculectomy for primary open angle glaucoma. METHODS: This prospective case series followed cases which had cataract extraction and Molteno implant insertion (45 eyes) or trabeculectomy (94 eyes) followed up for a mean of 5.3 years and 3.9 years respectively. RESULTS: Cataract extraction and Molteno implant insertion or trabeculectomy controlled the intraocular pressure at 21 mmHg or less with a probability of 1.00 (95% CI 0.93 to 1.00) at 10 years or more after operation and 0.94 (95% CI 0.89 to 0.99) and 0.73 (95% CI 0.46 to 0.99) at five and 10 years after operation respectively. CONCLUSIONS: Cataract extraction combined with insertion of Molteno implants or trabeculectomy controlled the intraocular pressure in 100% (45/45) and 94% (88/94) of cases respectively.     

Otago Glaucoma Surgery Outcome Study: factors controlling capsule fibrosis around Molteno implants with histopathological correlation

OBJECTIVE: To describe the histopathology of Molteno implant capsules in cases of primary and secondary glaucoma and to correlate them with surgical technique and clinical outcomes in quiet eyes. DESIGN: Human tissue study with clinicopathological correlation. MATERIALS: Seventy-five autopsy eyes or surgical pathology specimens obtained between 4 days and 23 years after insertion of Molteno implants were studied. Basic histologic features common to all bleb capsules were described, and the thickness was measured in 28 specimens from quiet eyes. MAIN OUTCOME MEASURES: Histologic features of capsules, including wall thickness, distribution of inflammatory cells, and presence or absence of fibrodegeneration, were assessed by light microscopy. RESULTS: Without aqueous flow (first stage of 2-stage insertion), the episcleral plates of Molteno implants were encapsulated by a very thin (20-60 micro m) avascular collagenous layer. The second stage of 2-stage insertion, with delayed drainage of aqueous and early temporary postoperative intraocular pressure (IOP) increase to 25 to 35 mmHg, produced thin (190-250 micro m) permeable capsules with fewer fibrovascular than fibrodegenerative components. Insertion of nonligatured implants with immediate aqueous flow produced thicker capsules (300-600 micro m) composed of an outer fibrovascular layer and an inner fibrodegenerative layer of approximately equal thickness. Three-stage insertion of modified Molteno implants with temporary externalization of aqueous flow onto the conjunctival surface and postoperative IOP not exceeding 12 mmHg produced the thickest (375-700 micro m) heavily fibrosed and impermeable capsules composed entirely of dense fibrovascular tissue without a fibrodegenerative layer. CONCLUSIONS: Capsules around functioning Molteno implants evolved through a series of histologic stages. Without aqueous flow, the episcleral plate of the implant stimulated encapsulation by a thin avascular collagenous layer. With aqueous flow, an immediate inflammatory reaction developed in the episcleral connective tissues that included collagenous and vascular components. After a variable delay, a fibrodegenerative process developed in the deeper layers of the capsule. The fibrodegenerative process may depend on sufficient increases of IOP for aqueous to displace interstitial tissue fluid from the deeper layers of the capsule. The final thickness and permeability of the capsule probably depend on the relative intensity and timing of these opposing processes, which were influenced by surgical technique and postoperative management.     

The development and management of neovascular glaucoma

Patients with neovascular glaucoma (NVG) often present with neovascularisation of the iris (NVI) already established and prompt energetic treatment of these patients is needed to reverse or stabilise the condition with possible retention of some visual function. In this series if the ocular media were still clear panretinal photocoagulation (PRP) caused regression of NVI in about 60% of cases and if a persistent rise in intraocular pressure (IOP) were still present this could be dealt with by drainage operation, Molteno implant or cyclophotocoagulation. If the media were already opaque or NVI did not regress then a Molteno implant or cyclophotocoagulation was used to reduce the IOP, preserving corneal endothelial function so that a comfortable eye could be obtained. Some regression of the NVI process was likely with time if the IOP were controlled by surgical treatment. Of 32 patients reviewed here, 20 patients developed NVG following a central retinal vein occlusion; in six patients NVG followed diabetic proliferative retinopathy, in five it followed arterial occlusion, and in one it followed an old traumatic retinal detachment. In those patients where NVG followed venous or arterial occlusion the common risk factors were always present. Patients were usually under treatment for their systemic condition but this treatment should be reviewed.     

Molteno implant and refractory glaucoma. Evaluation of postoperative IOP control and complications with a modified surgical procedure

BACKGROUND: Management of refractory glaucoma is difficult because classic medical and surgical treatments are ineffective in controlling highly elevated intraocular pressure (IOP). Drainage implants are an alternative to cyclodestructive procedures in refractory glaucoma. The double-plate Molteno implant, a tube linked to two polypropylene plates, allows aqueous humor drainage from the anterior chamber towards the posterior subconjunctival spaces. The main postoperative complication is severe hypotony, potentially responsible for a decrease in visual acuity in cases of advanced glaucoma. Surgical modifications such as external tube occlusion can reduce postoperative hypotony. However, tube occlusion may lead to transient postoperative hypertony. Our retrospective study reports on double-plate Molteno implantation with intraoperative external tube occlusion associated with trabeculectomy in some cases. MATERIAL AND METHODS: Thirteen eyes of 13 patients with refractory glaucoma were included in the study (5 cases of open angle glaucoma, 7 cases of secondary glaucoma, one case of primary congenital glaucoma). All had ocular hypertony despite maximal tolerable medical treatment; 84.5% had previously undergone trabeculectomy with mitomycin (1-5 procedures) and 61% had undergone cyclophotocoagulation (1-4 sessions). All underwent double-plate Molteno implantation with external tube occlusion between 1993 and 2001. In three cases, intraoperative trabeculectomy was also performed. Visual acuity, IOP, relevant medical treatment and potential complications were reported at each follow-up visit. Complete success was defined as IOP less than 21 mmHg without treatment, while IOP control with medical treatment was considered as relative success. RESULTS: Mean (+/-SD) follow-up was 2.9+/-2.1 years (range, 9 months to 8 years). Mean (+/-SD) initial and final IOPs were 35.2+/-7 mmHg and 17.1+/-5 mmHg, respectively, i.e., a 50% IOP decrease. Mean (+/-SD) initial and final medical treatments were, respectively, 4.3+/-1.5 (61% with systemic acetazolamide) and 1.3+/-1.4 (without acetazolamide). The complete success rate was 38.5% and relative success 92.3%. Immediate postoperative hypertony occurred in 60% of the cases with external tube occlusion alone (10 cases). This hypertony was controlled with medical treatment in 2/3 of the cases but required surgical reintervention in 1/3 of the cases. For patients with intraoperative trabeculectomy (3 cases), postoperative immediate IOP without medical treatment was 2, 5 and 8 mmHg respectively. Complications reported were flat anterior chamber (1 case), visual acuity decrease (4 cases), lens opacification (1 case), macular edema (1 case), corneal edema (2 cases: 1 transient, 1 corneal decompensation) and long-term refractory hypertony (1 case). CONCLUSION: The double-plate Molteno implant is effective in controlling IOP in refractory glaucoma. External tube occlusion prevents complications related to excessive filtration; however, it may lead to transient postoperative hypertony. This hypertony can be avoided when simultaneous trabeculectomy is performed. Corneal decompensation remains the major complication of this surgical procedure.     

Mitomycin C eliminates the short-term intraocular pressure rise found following Molteno tube implantation

Purpose: Molteno implants remain popular for treating recalcitrant glaucomas. This study aimed to assess the effect of mitomycin C (MMC) use with Molteno tube implantation upon intraocular pressure (IOP) control and complication rates. In particular, the study aimed to assess any change that MMC might have upon the postoperative hypertensive phase. Methods: A retrospective case record study was conducted of all patients undergoing double plate Molteno implant surgery by one surgeon over 5 years. Eyes with recalcitrant glaucoma unresponsive to previous surgery, or deemed unlikely to succeed with trabeculectomy, underwent double plate Molteno tube implantation. Eyes that had MMC (0.3 mg/mL, 3 min) applied to Tenon's capsule over the secondary plate were compared with eyes that underwent surgery without adjunctive MMC application. Results: Twenty‐seven eyes received MMC and were similar to 26 eyes not receiving MMC in terms of glaucoma subtype, age, sex, previous surgery, preoperative IOP and postoperative IOP lowering agents. Those not receiving MMC had raised IOP 31?90 days post implantation compared with MMC treated eyes (P < 0.01) and more often received oral antifibrosis medication (P < 0.05). Complications were no more common with MMC except for initial overdrainage. Significant systemic complications from the use of oral antifibrosis medication were common. Conclusions: The findings suggest a useful role for MMC. Caution is advised in case selection for MMC use. Mitomycin C treatment over the secondary plate alone permits removal of this plate if MMC‐related complications occur without requiring removal of the whole implant.     

Molteno aqueous shunt as a primary surgical intervention for uveitic glaucoma: long‐term results

Purpose: To evaluate the efficacy of Molteno aqueous shunt as a primary surgical treatment in uveitic glaucoma. Methods: Nonrandomized, interventional, retrospective clinical study. The intraocular pressure (IOP), survival rate and complications were analyzed in 30 patients with uveitic glaucoma treated with Molteno implant. Results: The mean follow‐up time was 59.3 ± 18.4 months. Preoperatively, the mean ± SD IOP was 32.8 ± 7.5 mmHg (range 20–48), and the mean number of medications was 3.1 ± 0.6. The mean IOP decreased significantly (p < 0.001) to 17.7 and 15 mmHg at 3 and 6 months postoperatively. The mean number of medications decreased statistically significantly (p < 0.001) from the preoperative number 3.1 to 1.9 three months postoperatively. The number of medications continued to decrease significantly up to 3 years postoperatively. The qualified success rate (Kaplan–Meier estimate) was 97%, 93%, 90% and 85% at 1, 2, 3 and 4 years, respectively. Two patients failed because of hypotony, two patients developed conjunctival erosion and one patient had corneal decompensation. Conclusions: Molteno aqueous shunt as the first glaucoma procedure decreased IOP effectively in uveitic glaucoma. Even after 4 years, the survival estimate was quite high. The IOP decreased continuously during the first year after the surgery, and the medication was slowly tapered even up to 3 years postoperatively. It is suggested that it may be possible to postpone further surgical intervention during the first postoperative year after Molteno implantation even if the IOP is not quite optimal.     

Molteno/von Denffer drainage implants in therapy-refractory glaucomas

BACKGROUND: In glaucoma eyes in which the pressure regulation was not possible with drugs and surgery or which were blind already, we treated the patients with a Molteno implant by von Denffer. MATERIALS AND METHODS: In 10 years (1995 to 2004) we treated 19 eyes with a glaucoma drainage device -- the Molteno implant developed by von Denffer. The average age of the patients was 64 (range: 15 to 77) years. On average 3,1 operations were realised before the implant. The average eye pressure was 44 mm Hg preoperatively. Our patients suffered from different glaucomatous diseases: 7 primary glaucomas (congenital, open and narrow angle glaucoma) and secondary: neovascular glaucoma (4), PEX glaucoma (2), traumatic glaucoma (3) and postoperative glaucoma (3). RESULTS: The intraocular pressure had a successful outcome of under 20 mm Hg in 13 eyes, 5 patients out of these were treated with 1 to 3 drugs. Early complications (flat anterior chamber, hyphaema, hypotonia) were reversible. Late complications were phthisis bulbi (3), explantation of the implant (2) and one evisceration bulbi. We found an improvement of the visual acuity in 4 cases in traumatic and postoperative glaucoma. The stabilisation of visual acuity was possible in primary glaucoma. CONCLUSIONS: The implantation of the Molteno implant by von Denffer is an ultimate ratio in eyes with persistent high intraocular pressure. A durable reduction of the pressure is possible in two-thirds and the conservation of the bulbus was achieved in three-fourths of the patients.     

Molteno implants in children

We report our experience with Molteno implants in 27 eyes of 20 children with glaucoma. Associated ocular findings included Sturge Weber syndrome (one patient), aniridia and retinoschisis (one patient), aphakia (seven patients, eight eyes), rubella syndrome (two patients), Peters anomaly (one patient), and Treacher Collins syndrome (one patient). Fifteen eyes received a single-plate implant, and 12 eyes received a double-plate implant in two stages. The patients' ages ranged from 2 months to 13 years (mean 47 +/- 55 months). The average number of previous glaucoma procedures was four per eye (range two to 10). The follow-up period ranged from 6 to 36 months (mean 20 +/- 9 months). The mean intraocular pressure before surgery was 34 +/- 4 mm Hg. The mean postoperative intraocular pressure was 19 +/- 11 mm Hg at 1 month and 19 +/- 6 mm Hg at 1 year (p < 0.001 at both times). After surgery nine eyes (33.3%) required no medication for control of intraocular pressure. Additional surgery was required in 12 eyes (44.4%). We believe the Molteno implant is a useful approach for children with glaucoma who fail to respond to standard medical and surgical treatments.     

Surgical outcomes of combined phacoemulsification and glaucoma drainage implant surgery for Asian patients with refractory glaucoma with cataract

PURPOSE: To examine the safety and efficacy of combined phacoemulsification and glaucoma drainage implant surgery in providing reduction of intraocular pressure (IOP) and visual rehabilitation in eyes with refractory glaucoma and cataract. DESIGN: Interventional case series. METHODS: A retrospective chart review was performed on all subjects who underwent combined phacoemulsification with intraocular lens implantation and glaucoma drainage implant surgery by a single surgeon at the National University Hospital, Singapore. The implants used were the 185 mm2 Ahmed glaucoma valve and the 350 mm2 Baerveldt glaucoma implant. In terms of IOP, a complete success was defined as IOP of between 6 to 21 mm Hg without medication, qualified success as IOP between 6 to 21 mm Hg with one or more medication, and failure as a sustained IOP of >21 mm Hg or <6 mm Hg with or without one or more medication on two or more visits. RESULTS: A total of 32 combined phacoemulsification and glaucoma implant surgeries in 32 patients was performed. All patients were of Asian origin, and the mean age was 58 +/- 16 years (range, 20-78 years). The Baerveldt glaucoma implant and Ahmed glaucoma valve implant were inserted in 16 eyes each. With a mean follow-up of 13 +/- 5 months (range 6 to 22 months), IOP was reduced from a mean of 28.0 +/- 11.5 mm Hg to 15.2 +/- 6.0 mm Hg postoperatively (P <.0001), whereas the number of antiglaucoma medications decreased from a mean of 2.4 +/- 1.4 to.3 +/-.7 (P <.0001) at last follow-up. Overall, there were 24 eyes (75%) that were classified as complete successes, 4 eyes (12.5%) that were qualified successes, and 4 eyes that failed (12.5%). Twenty-three eyes (72%) had improvement of visual acuity, while only one eye had a loss of more than 1 line of Snellen acuity. There was no case that encountered an intraoperative complication, and postoperative complications occurred in 12 eyes (38%), the most common of which was hypotony (in six eyes, 19%). CONCLUSION: For subjects with refractory glaucoma and cataract, combined phacoemulsification and glaucoma drainage implant surgery provide good visual rehabilitation and control of IOP, with low incidence of complications.     

Molteno implant for control of glaucoma in eyes after penetrating keratoplasty

Seventeen patients (17 eyes) underwent implantation of a single plate Molteno implant for medically uncontrollable intraocular pressures after penetrating keratoplasty. Most of the eyes had extensive peripheral anterior synechiae, and 16 of 17 (94%) were pseudophakic or aphakic following keratoplasty. Other glaucoma procedures had been performed previously on 13 eyes: argon laser trabeculoplasty (one eye), trabeculectomy (seven eyes), transpupillary argon laser cyclophotocoagulation (three eyes), and cyclocryotherapy (three eyes). Follow-up ranged from 5 to 28 months (mean, 13 months). Three eyes underwent repeat Molteno implantation when intraocular pressure (IOP) was not satisfactorily reduced after the first procedure. Considering one eye with chronic hypotony as a failure, 12 of 17 eyes (71%) had IOPs of less than 21 mmHg at the time of the three most recent postoperative examinations after a single Molteno implant. Repeat implants in three eyes increased the number of eyes with IOPs of less than 21 mmHg to 14 (82%). Corneal allograft rejection after Molteno implantation occurred in seven eyes; two of these were successfully reversed with corticosteroid therapy. Three of the five eyes with irreversible graft rejection were regrafted, and two of these grafts have remained clear. Including the regrafted eyes, 13 eyes had clear grafts and controlled IOPs at the most recent postoperative examination. The Molteno implant may prove useful in the management of medically uncontrollable glaucoma following penetrating keratoplasty; however, there appears to be a substantial risk of postoperative graft rejection.     

Glaucoma drainage devices: a review of the past, present, and future

Glaucoma drainage devices are more frequently being used for glaucoma filtering surgeries, even those at low risk for failure with trabeculectomy. There are 4 major devices available: the Molteno, Baerveldt, Krupin, and Ahmed. The Molteno and Baerveldt are non-valved implants, while the Krupin and Ahmed are valved. The success rates of the different valves are about equal at approximately 70% with a mean intraocular pressure (IOP) lowering of at least 50% from the pre-operative IOP. Unfortunately, the failure rate is about 10% per year, leading to only 50% functional drainage devices at 5 years. Therefore, research on the biomaterials, shape, and technique of drainage implant surgery is being done in hopes of increasing long term success rates.     

Glaucoma Drainage Devices: A Review of the Past,Present, and Future

Glaucoma drainage devices are more frequently being used for glaucoma filtering surgeries, even those at low risk for failure with trabeculectomy. There are 4 major devices available: the Molteno, Baerveldt, Krupin, and Ahmed. The Molteno and Baerveldt are non-valved implants, while the Krupin and Ahmed are valved. The success rates of the different valves are about equal at approximately 70% with a mean intraocular pressure (IOP) lowering of at least 50% from the pre-operative IOP. Unfortunately, the failure rate is about 10% per year, leading to only 50% functional drainage devices at 5 years. Therefore, research on the biomaterials, shape, and technique of drainage implant surgery is being done in hopes of increasing long term success rates.     

Outcome of graft free Molteno tube insertion

AIMS: To determine the long term outcome of Molteno implants inserted using a modified surgical technique that eliminates the need for a donor scleral graft. METHODS: Retrospective case series involving a medical record analysis of 35 consecutive patients undergoing first Molteno implant surgery for refractory glaucoma. The main outcomes included life table analysis of intraocular pressure control following surgery and frequency of intraoperative and postoperative complications. RESULTS: There were no complications related specifically to the modified method of tube placement. Medium term intraocular pressure control was similar to other series. CONCLUSIONS: This simplified method for the insertion of Molteno implants eliminates the need for a donor scleral graft while maintaining the implant's ability to control intraocular pressure.     

The development and management of neovascular glaucoma.

Patients with neovascular glaucoma (NVG) often present with neovascularisation of the iris (NVI) already established and prompt energetic treatment of these patients is needed to reverse or stabilise the condition with possible retention of some visual function. In this series if the ocular media were still clear panretinal photocoagulation (PRP) caused regression of NVI in about 60% of cases and if a persistent rise in intraocular pressure (IOP) were still present this could be dealt with by drainage operation, Molteno implant or cyclophotocoagulation. If the media were already opaque or NVI did not regress then a Molteno implant or cyclophotocoagulation was used to reduce the IOP, preserving corneal endothelial function so that a comfortable eye could be obtained. Some regression of the NVI process was likely with time if the IOP were controlled by surgical treatment. Of 32 patients reviewed here, 20 patients developed NVG following a central retinal vein occlusion; in six patients NVG followed diabetic proliferative retinopathy, in five it followed arterial occlusion, and in one it followed an old traumatic retinal detachment. In those patients where NVG followed venous or arterial occlusion the common risk factors were always present. Patients were usually under treatment for their systemic condition but this treatment should be reviewed.     

Argon laser trabeculoplasty and reduction of ocular hypotensive medication used by glaucoma patients

BACKGROUND: We studied the effect of argon laser trabeculoplasty (ALT) on medically controlled, pressure-stable glaucoma patients to verify whether it is possible to reduce ocular hypotensive medication after ALT while keeping intraocular pressure levels similar to those observed before the procedure. METHODS: Seventy-one consecutive chronic glaucoma patients, all of whom were taking ocular hypotensive medication and had intraocular pressure at adequate levels, underwent ALT. After the laser procedure, each patient discontinued one hypotensive drug. Mean follow-up was 16.39 +/- 5.39 months. We performed diurnal pressure curves on each patient before and after trabeculoplasty to determine the effect on intraocular pressure. RESULTS: In 39 (54.9%) patients, it was possible to reduce ocular hypotensive medication and still maintain intraocular pressure levels similar to those achieved before ALT. INTERPRETATION: For some medically controlled, chronic glaucoma patients, ALT can reduce the amount of ocular hypotensive medication without significantly altering intraocular pressure.     

Comparison of the Ahmed Glaucoma Valve,the Krupin Eye Valve with Disk,and the double-plate Molteno implant

OBJECTIVE: To compare the efficacy of the nonvalved double-plate Molteno implant with two valved implants, the Krupin Eye Valve with Disc and the Ahmed Glaucoma Valve, in the treatment of recalcitrant glaucoma. PATIENTS AND METHODS: The authors performed a nonrandomized retrospective review of patients who received the Molteno implant (n = 27), Krupin Eye Valve with Disc (n = 13), or Ahmed Glaucoma Valve (n = 13), with adjunctive mitomycin C. RESULTS: Kaplan-Meier life-table analysis showed that the Molteno implant patients were more likely to maintain an intraocular pressure between 5 and 15 mm Hg than Ahmed Glaucoma Valve patients (P = 0.03). Success rates at 1 year were 80% (95% CI, 66-97%) for the Molteno implant, 39% (19-77%) for the Krupin Eye Valve with Disc, and 35% (15-82%) for the Ahmed Glaucoma Valve. However, Ahmed Glaucoma Valve patients were less likely to experience complications requiring reoperation or loss of two or more lines of visual acuity (P < 0.01) than Molteno implant or Krupin Eye Valve with Disc patients. CONCLUSIONS: This nonrandomized study suggests that the Molteno implant with mitomycin C is more likely to result in intraocular pressures in the lower teens than the Ahmed Glaucoma Valve with mitomycin C. The findings suggest that the Ahmed implant is less likely to create problems leading to reoperations or visual acuity loss than the Molteno or Krupin implants.     

MANAGEMENT OF UNCONTROLLED GLAUCOMA WITH THE MOLTENO SYSTEM

In glaucomatous eyes refractory to medication, laser techniques and conventional drainage surgery, intraocular pressure is often high, and visual loss rapid. In this situation a reliable, robust artificial outflow system is required. Molteno has evolved a plastic tube and plate device combined with a fibrosis suppression medication regimen. Thirty-eight eyes of 32 patients with uncontrolled glaucoma were treated with the Molteno system. Six months after operation mean intraocular pressure had been reduced from 41.0 ± 13.6 to 16.2 ± 5.6 mmHg. Eighteen eyes had pressures of 20 mmHg or less on no hypotensive therapy, 17 on reduced treatment. Three eyes had a pressure of 21 to 35 mmHg on treatment at six months. The 13 aphakic eyes responded as well as 25 phakic eyes. Five eyes with rubeotic glaucoma demonstrated pressures of less than 20 mmHg without therapy, four eyes with traumatic glaucoma required continuing medication with three having pressures below 22 mmHg. Of the seven eyes with uveitic glaucoma, one was lost, two required maintenance therapy; five of six surviving eyes had pressures below 20 mmHg. Fifteen eyes with congenital or juvenile glaucoma achieved pressures below 20 mmHg, three of these with timolol drops, three with timolol and acetazolamide, and nine with no treatment. While seven of seven eyes with refractory primary open-angle glaucoma attained pressures below 20 mmHg. all seven needed continuing mild hypotensive therapy. Eleven eyes underwent a one-stage procedure, while 27 eyes required a two-stage operation. Twenty-eight eyes received fibrosis suppression medication after the second stage, and 24 maintained or improved their preoperative visual acuity. Results have been encouraging: in general the Molteno system is recommended as the second drainage operation in all glaucomatous eyes in which conventional therapy has failed, and as the primary surgical procedure (after laser techniques) in eyes with rubeotic and uveitic glaucoma. Ciliary body destructive procedures should be restricted to control of symptoms in blind eyes.