Treatment outcomes in the tube versus trabeculectomy study after one year of follow-up

The medical and surgical treatment of glaucoma

BACKGROUND

Ongoing demographic changes in Europe are heightening the importance of adequate treatment for glaucoma, a disorder that is markedly more common in the elderly.

METHOD

A selective search for relevant literature, including Cochrane Reviews and the guidelines of the European Glaucoma Society, regarding the topical and surgical treatment of glaucoma.

RESULTS

It is recommended that the intraocular pressure (IOP) should be lowered by 20% to 50% from its baseline value, depending on the extent of already existing damage, the rate of progression, the baseline IOP, and the age of the patient. Topical monotherapy can lower the IOP by 15% to 30%. The success rate of filtration surgery has risen because of the intraoperative application of topical antimetabolites and currently ranges from 50% to 90%, depending on the study.

CONCLUSIONS

The goal of glaucoma treatment is to protect the patient from blindness and visual impairment while keeping the treatment-related decline in quality of life to a minimum. Any type of glaucoma treatment, be it medical or surgical, must further this aim in consideration of the situation of the individual patient.

Replacement of Ahmed aqueous drainage devices in eyes with device-related complications

PURPOSE

To examine the results of removal and simultaneous replacement of Ahmed aqueous drainage devices (ADDs), which require removal due to complications.

METHODS

Noncomparative retrospective case series of 6 patients.

RESULTS

For the period from January 1999 to December 2007, 325 Ahmed ADD insertions were performed in 272 patients. From this, we identified 6 patients (1.8%) who underwent removal of an ADD for device-associated complications. All had replacement of the Ahmed ADD in a different quadrant at the same surgery. The mean time interval from the original valve insertion was 31.2 months (median, 32.5; range, 3 to 67 mo). The indication for tube removal was chronic uveitis in 3 patients, plate exposure in 2 patients, and tube exposure in 1 patient. We examined the results at 12 months postsimultaneous removal and replacement of the ADD and at final follow-up (median, 25 mo; range, 13 to 52 mo). The preoperative complications resolved in all cases, with the inflammation settling postoperatively in the patients with preoperative uveitis and no patients developing tube or plate exposure at last follow-up. The mean preoperative intraocular pressure (IOP) was 16.0 mm Hg (median, 15.0; range, 9 to 29 mm Hg). At 12 months and final review, the mean IOP was 10.8 mm Hg (median, 10.0; range, 1 to 24 mm Hg) and 11.0 mm Hg (median, 10.0; range, 3 to 24 mm Hg), respectively. The mean number of glaucoma medications preoperatively was 2.8 (median, 3.5; range, 0 to 5). This was reduced to 1.7 (median, 1.5; range, 0 to 4) at 12 months and 2.2 (median, 1.5; range, 0 to 5) at final follow-up. Of the 6 cases in this series, 4 (66.6%) were considered to have adequate IOP control postoperatively. One patient developed postoperative hypotony, with an IOP of 4 mm Hg and reduced vision due to hypotony maculopathy. This patient declined further surgical intervention. One patient had a preoperative IOP of 29 mm Hg on 4 drops and acetazolamide 250 mg b.i.d. At 14 months postsurgery, IOP was 24 mm Hg on 4 drops and the patient underwent insertion of a second ADD. At last follow-up 14 months later, IOP was 10 mm Hg on 4 drops. There were no other significant intraoperative or postoperative complications in this series.

CONCLUSIONS

In patients who require removal of Ahmed ADDs due to complications, removal of the offending ADD and replacement in another quadrant is effective in both resolving the complications and maintaining IOP control.

Second Ahmed valve insertion in the same eye

PURPOSE

To examine the results of same-eye second Ahmed glaucoma drainage device (GDD) insertion in eyes with refractory glaucoma despite previous Ahmed GDD insertion and maximal tolerated medical therapy.

METHODS

Noncomparative retrospective case series.

RESULTS

Twenty-one patients who had undergone 2 GDD surgeries in the same eye were identified. Following chart review, 19 patients had follow-up of at least 1 year and were included in the analysis. All surgeries involved Ahmed valves. The mean drop in intraocular pressure (IOP) at 12 months and at final follow-up was 8 (43%) and 7.9 mm Hg (42%), respectively. The mean number of glaucoma medications used postoperatively (2.4 at 12 mo and 2.6 at final follow-up) was significantly less than preoperatively (4.1). Although the mean visual acuity was poorer postoperatively, this did not reach statistical significance. Sixteen of the 19 patients (84.2%) were defined as complete or partial success, as they achieved IOP of >/=5 and </=21 mm Hg and >/=20% decrease on preoperative IOP with or without glaucoma drops. Three patients were considered complete failures at 12 months and final follow-up. There were no significant intraoperative complications. One patient (5.3%) required anterior chamber reformation on day 1 postoperatively. One patient (5.3%) suffered a decrease in vision from 20/70 preoperatively to counting fingers postoperatively owing to corneal decompensation.

CONCLUSIONS

Second Ahmed GDD surgery seems to be a safe and effective option when IOP remains uncontrolled despite previous GDD implantation.

Tube shunt complications and their prevention

PURPOSE OF REVIEW

Glaucoma drainage devices (GDDs) have been generally accepted as a treatment of refractory glaucoma. GDDs have their own unique set of complications that are important to evaluate to prevent them.

RECENT FINDINGS

Tube shunts are typically used in eyes with refractory glaucoma. There is increased interest in studying the efficacy of GDDs. Most of the attention has been focused on comparing trabeculectomy with the Baerveldt implant (Advanced Medical Optics, Inc., Santa Anna, California, USA). The other leading implant is the Ahmed Glaucoma Valve. There are several retrospective studies comparing these two devices and a prospective study is ongoing. There is great interest in the complication rate of tube shunts and these have been published both retrospectively and prospectively. Complications such as hypotony, diplopia, strabismus, proptosis, tube erosion, failure, corneal decompensation, endophthalmitis, and visual loss are all important and some have recently been reviewed in the literature. Moreover, the use of glaucoma drainage implants in the pediatric population has been evaluated.

SUMMARY

Glaucoma drainage implants have been a powerful tool in our surgical fight to prevent blindness; however, they are not without complications or controversy.

Canal surgery in adult glaucomas

PURPOSE OF REVIEW

Outflow procedures for glaucoma surgery have remained popular in the last decade, including trabeculectomy, glaucoma drainage devices, and deep sclerectomy/viscocanalostomy. In the last few years, the surgical armamentarium for glaucoma has vastly increased. Surgeons are using more procedures aimed at creating bleb-free surgery. Schlemm's canal surgery is experiencing a renaissance. This article concentrates on three of the more commonly performed canal procedures: trabeculotomy ab interno (Trabectome), Canaloplasty, and trabeculotomy ab externo.

RECENT FINDINGS

Trabeculotomy ab interno performed with the Trabectome has been shown to lower intraocular pressure (IOP) almost 40% by 12 months with minimal complications. Trabectome alone, as well as combined with cataract surgery, appears to lower IOP quite well. Canaloplasty has also been shown to lower IOP by 38% and combined with cataract surgery, IOP was lowered 44% at 24 months. Trabeculotomy lowers IOP well, especially in older adults. Phacotrabeculotomy lowers IOP to 21 mmHg or less in 84% of patients with supplemental use of medications, and in 36% of patients without at 3 years.

SUMMARY

Canal surgery has proven to be an alternative to traditional glaucoma surgery, lowering IOP relatively well. Surgeons must be comfortable with the anatomy and proceed with the procedure in eyes that are amenable to various new surgical advances.

Reducing the visual burden of glaucoma in Asia: what we know and what we need to know

Despite great progress in elucidating risk factors and effective treatments for eye disease in the last decades, blindness prevalence in the developing and developed world is either static or rising. A research agenda is needed to develop and test specific strategies to reduce the burden of blindness from glaucoma and other common eye diseases. Current knowledge about open and closed-angle glaucoma is reviewed and a strategy to reduce glaucoma blindness in Asia is suggested. A critical component of this strategy is enhanced training in the detection of narrow angles and optic nerve damage by direct examination. Specific research topics that could inform such a strategy are outlined.

Ex-PRESS mini glaucoma shunt: surgical technique and review of clinical experience

Glaucoma is a leading cause of worldwide blindness. Treatment of this chronic disease, centered on lowering intraocular pressure (IOP), may require surgical intervention when medical and/or laser therapy fail to control IOP. Traditional glaucoma surgery, such as trabeculectomy, has been performed for decades and has a proven track record of success. Unfortunately, many complications such as hypotony and slow visual recovery are known to occur and can lead to significant patient morbidity. New devices are being developed to allow surgeons increased control with more predictable postoperative results. One such device, the Ex-PRESS mini glaucoma shunt, has undergone changes in design and method of insertion making it more appealing for use in patients requiring IOP-lowering surgery. We summarize pertinent literature and expand on the future role of this device in glaucoma surgery.

Internal glaucoma drainage device tube fenestration for uncontrolled postoperative intraocular pressure

PURPOSE

To describe a novel approach to early postoperative intraocular pressure (IOP) control after glaucoma drainage device (GDD) implantation.

METHODS

Two patients with elevated IOP after GDD implantation underwent internal GDD tube fenestration using a 30-gauge needle to perforate the GDD tube.

RESULTS

IOP was lowered in each case by over 50% without complication.

CONCLUSIONS

Transanterior chamber internal GDD tube fenestration is a novel, straightforward approach to early IOP control after GDD implantation. This procedure adds to our armamentarium of methods for controlling IOP during the early postoperative period.

Modern concepts in antiglaucomatous implant surgery

BACKGROUND

Antiglaucomatous implant surgery is a continously evolving field in glaucoma treatment.

METHODS

A literature search with the terms "glaucoma implant surgery", "aqueous shunts" and "glaucoma drainage devices" was carried out, especially giving prominence to innovative surgical developments in glaucoma implant surgery and to recently established clinical evidence on traditional shunt surgery.

RESULTS

Episcleral glaucoma drainage devices have recently proven their efficacy in large studies. Longterm data about their clinical efficacy and their risk/safety profile are sufficiently available. New antiglaucomatous devices try to target alternative drainage routes, for example trabecular or uveoscleral outflow. Valid longterm data from prospective randomized clinical trials are not available for these devices as yet.

CONCLUSIONS

Although valid data on clinical application of the new glaucoma implants are not available as yet, profound knowledge about their theoretical concept and their practical management is obligatory for all glaucoma clinicians.

Ahmed valve implantation with adjunctive mitomycin C and 5-fluorouracil: long-term outcomes

PURPOSE

To evaluate long-term outcomes after Ahmed valve implantation in patients with glaucoma when using adjunctive intraoperative mitomycin C (MMC) and postoperative 5-fluorouracil (5-FU).

DESIGN

Retrospective, interventional, consecutive case series.

METHODS

A consecutive series of eyes undergoing Ahmed valve implantation, either alone (AHMED eyes) or in combination with cataract surgery (AHMED+PHACO), using both intraoperative MMC and postoperative 5-FU were evaluated. Failure was defined as the first occurrence of any of the following: 1) the first of three consecutive visits where intraocular pressure (IOP) was >18 mm Hg or <20% IOP reduction from baseline and the final number of topical medications was not reduced by at least two from baseline, 2) the need for additional surgery, or 3) the development of serious complications.

RESULTS

A total of 130 eyes underwent Ahmed valve implantation with intraoperative exposure to 0.5 mg/ml MMC (median time: eight minutes; range, four to 10) and postoperative subconjunctival injections of 5 mg of 5-FU (median: five injections; range, zero to nine). Kaplan-Meier estimates of the cumulative probability of valve success and confidence interval (CI) at the sixth follow-up year were 0.72 (95% CI, 0.59 to 0.82) for AHMED eyes (n = 88), 0.84 (95% CI, 0.65 to 0.93) for AHMED+PHACO eyes (n = 42). A median of two fewer medications were required relative to baseline for both AHMED and AHMED+PHACO eyes.

CONCLUSIONS

The adjunctive use of both intraoperative MMC and postoperative 5-FU with Ahmed valve implantation results in high success rates. IOP was well controlled in the majority of patients within the six-year postoperative period.

Longitudinal rates of postoperative adverse outcomes after glaucoma surgery among medicare beneficiaries 1994 to 2005

PURPOSE

To determine longitudinal rates of postoperative adverse outcomes after incisional glaucoma surgery in a nationally representative longitudinal sample.

DESIGN

Retrospective, longitudinal cohort analysis.

PARTICIPANTS

Medicare beneficiaries >or=68 years who underwent a primary trabeculectomy (PT), trabeculectomy with scarring (TS), or glaucoma drainage device (GDD) implantation from 1994 to 2003 with follow-up through 2005.

INTERVENTION

Primary trabeculectomy, TS, and GDD were identified from International Classification of Diseases (ICD-9-CM) and Current Procedural Terminology (CPT) procedure codes. Change in rates of postoperative adverse outcomes associated with these 3 surgical interventions was analyzed by cumulative incidence rates and Cox proportional hazards model regression; regression analysis controlled for prior adverse outcome measures (3-year run-up) and demographic variables.

MAIN OUTCOME MEASURES

First-, second-, and sixth-year cumulative rates and probability of experiencing serious adverse outcomes (retinal detachment, endophthalmitis, suprachoroidal hemorrhage), less serious adverse outcomes (choroidal detachment, corneal edema, hypotony), and receipt of additional glaucoma surgery were identified through Medicare claims for each treatment group.

RESULTS

At the 1-year follow-up, rates of severe adverse outcomes were higher among beneficiaries in the GDD group (2.0%) relative to the PT (0.6%) and TS groups (1.3%). Controlling for prior adverse outcomes to the surgery and demographic factors in Cox proportional analysis, differences were often reduced, but generally remained statistically and clinically significant. Rates of severe outcomes, less severe outcomes, corneal edema, and low vision/blindness were higher for persons undergoing GDD than PT or TS. However, rates of reoperation were higher for TS than GDD.

CONCLUSIONS

The risk for adverse outcomes was higher in GDD than in PT surgery or TS, controlling for a number of important case mix and demographic factors.

A panel assessment of glaucoma management: modification of existing RAND-like methodology for consensus in ophthalmology. Part II: Results and interpretation

PURPOSE

To present the results of a panel consensus assessment of evaluation and therapy relating to primary open-angle glaucoma based on available evidence and expert opinion.

DESIGN

A panel consensus assessment of glaucoma diagnosis and therapy using a modified RAND-like appropriateness methodology.

METHODS

One hundred and forty-eight questions, most of which related to glaucoma therapy, were created by a core nonvoting executive committee based on common clinical questions. An evidence-based review of the literature pertaining to these questions was provided to 10 voting panelists. These panelists, who did not participate in either the creation of the questions or the conduct of the literature review, then were polled using a modified technique derived from existing methodology.

RESULTS

Consensus agreement or disagreement was reached for 55.4% and 74.3% of the polling statements before and after the panel meeting, respectively. This represents a consensus agreement or disagreement on a majority of polling statements both before and after a meeting of all panelists and the two co-chairs of the program. There was an increase in the proportion of statements where consensus agreement was reached after the panel meeting.

CONCLUSIONS

Given the paucity of high-quality evidence relating to many of the issues addressed in this assessment and the variability of practice patterns among ophthalmologists, consensus agreement or disagreement was reached for a high proportion of polling statements.

Modern aqueous shunt implantation: future challenges

The aqueous shunts that are currently available are based on the principles of the Molteno implant, i.e., a permanent sclerostomy, routing of aqueous to the equatorial subconjunctival space, and an end plate to prevent obstruction, and also to determine the surface area for absorption. While the Ahmed Glaucoma Valve appears to have improved the predictability of early intraocular pressure (IOP) control, the Baerveldt Glaucoma Implant has a tendency towards a lower rate of long-term excessive encapsulation. As a result of improvements in predictability, shunts are used more widely. Because of these positive factors, and ongoing concerns regarding the bleb-related problems associated with mitomycin C trabeculectomy, there is an increasing interest in the use of shunts as primary surgical management for primary glaucoma. At present, the main barrier to wider use of shunts in less-complicated glaucomas will probably be the unknown long-term effect on corneal endothelium, an issue that has not yet been properly addressed.

Utilization of Various Glaucoma Surgeries and Procedures in Medicare Beneficiaries from 1995 to 2004

OBJECTIVE

To observe how the treatment of glaucoma has changed over the last decade.

DESIGN

Retrospective, observational, population-based analysis.

PARTICIPANTS

Medicare beneficiaries between 1995 and 2004.

METHODS

Medicare fee-for-service data claims between 1995 and 2004 were analyzed to determine the number of penetrating surgeries and laser procedures performed for glaucoma in the decade spanning 1995 and 2004.

MAIN OUTCOME MEASURE

Number of Medicare beneficiaries receiving glaucoma-related laser procedures or surgery.

RESULTS

Trabeculectomies in eyes without previous surgery or trauma decreased 53% over the study period, from 51,690 in 1995 to 24,178 in 2004, although trabeculectomy in eyes with scarring increased 9%. The number of aqueous shunting devices placed rose 184%, from 2728 in 1995 to 7744 in 2004. Cyclophotocoagulation procedures rose 248% over the study period, from 3264 procedures in 1995 to 11,356 procedures in 2004. Between 1995 and 2001, the number of laser trabeculoplasties decreased 57%, from a high of 151,244 in 1995 to a low of 75,647 in 2001. From 2001 to 2004, the number of trabeculoplasties more than doubled, with 157,490 performed in 2004. The number of laser iridotomies showed little fluctuation, increasing 18% over the study period and ranging from 63,773 to 85,286 every year. Over the study period, surgical iridectomies, including peripheral and sector iridectomies, decreased 66%, from a total of 4842 in 1995 to 1654 in 2004. Fistulization procedures other than trabeculectomy (including the Scheie and Holt procedures and iridencleisis) dropped 83% over the study period, decreasing from 2833 in 1995 to 478 in 2004.

CONCLUSIONS

Medicare recipients with glaucoma are more likely to be treated with aqueous shunting procedures or cyclophotocoagulation and less likely to be treated with trabeculectomy, compared with past years. After a decline in use between 1995 and 2001, laser trabeculoplasty increased substantially from 2001 to 2004. Fistulization procedures other than trabeculectomy and surgical iridectomy have become very uncommon.

Long-term outcomes of Ahmed glaucoma valve implantation in refractory glaucomas

PURPOSE

To evaluate the long-term efficacy of intraocular pressure (IOP) reduction and complications of Ahmed glaucoma valve (AGV) implantation (New World Medical, Inc, Rancho Cucamonga, California, USA) in refractory glaucoma.

DESIGN

Retrospective cohort study.

METHODS

Retrospective medical records from 64 patients (78 eyes) with refractory glaucoma who underwent AGV implantation with a minimum of three years of follow-up were reviewed. Data regarding age, gender, race, eye laterality, specific glaucoma diagnosis, best-corrected visual acuity (BCVA), number of medications, IOP, visual fields, surgical complications, and follow-up interval were collected from all visits and were analyzed. The primary outcome measure was cumulative probability of success defined as IOP of less than 21 mm Hg and of 5 mm Hg or more with a minimum of 15% reduction from baseline IOP, without additional glaucoma surgery or loss of light perception. Secondary outcomes included IOP and number of medications at three, six, 12, 24, 36, 48, and 60 months after surgery, surgical complications, and final BCVA.

RESULTS

The cumulative probability of success was 80% and 49% at one and five years, respectively. IOP was reduced from a mean of 30.4 +/- 10.7 mm Hg to 17.0 +/- 5.0 mm Hg at 12 months and 15.9 +/- 3.0 mm Hg at 60 months (P < .001). The number of medications decreased from 3.2 +/- 1.0 medications at baseline to 1.6 +/- 0.4 at 12 months and 2.1 +/- 0.2 at 60 months (P < .001). Prior glaucoma surgery and the silicone type of AGV were statistically significant risk factors for failure (P < .001).

CONCLUSIONS

Approximately 50% of single-plate AGV implantations in refractory glaucoma were considered successful after five years of follow-up. Prior glaucoma surgery was a statistically significant risk factor for failure.

Surgical complications in the Tube Versus Trabeculectomy Study during the first year of follow-up

PURPOSE

To describe the intraoperative and postoperative complications encountered during the first year of follow-up in the Tube Versus Trabeculectomy (TVT) Study.

DESIGN

Multicenter randomized clinical trial.

METHODS

SETTING

Seventeen clinical centers.

STUDY POPULATION

Two hundred twelve patients aged 18 to 85 years who had undergone previous trabeculectomy and/or cataract extraction with intraocular lens implantation and uncontrolled glaucoma with intraocular pressure > or =18 mm Hg and < or =40 mm Hg on maximum tolerated medical therapy.

INTERVENTIONS

A 350-mm(2) Baerveldt glaucoma implant or trabeculectomy with mitomycin C (MMC).

MAIN OUTCOME MEASURES

Surgical complications, reoperation for complications, visual acuity, and cataract progression.

RESULTS

Intraoperative complications occurred in seven patients (7%) in the tube group and 10 patients (10%) in the trabeculectomy group (P = .59). Postoperative complications developed in 36 patients (34%) in the tube group and 60 patients (57%) in the trabeculectomy group during the first year of follow-up (P = .001). Surgical complications were associated with reoperation and/or loss of > or =2 lines of Snellen visual acuity in 18 patients (17%) in the tube group and 28 patients (27%) in the trabeculectomy group (P = .12).

CONCLUSIONS

There were a large number of surgical complications during the first year of follow-up in the study, but most were self-limited. The incidence of postoperative complications was higher after trabeculectomy with MMC than nonvalved tube shunt surgery. Serious complications resulting in reoperation and/or vision loss occurred with similar frequency with both surgical procedures.