Viscocanalostomy Versus Trabeculectomy in Patients with Bilateral High-tension Glaucoma

Prospective Cohort Study on Refractive Changes after Trabeculectomy

We prospectively evaluated refractive changes in the eyes of 97 patients who underwent trabeculectomy at Fukui University Hospital, Fukui, Japan. The primary outcome measure was the refractive change after trabeculectomy. Secondary outcome measures included postoperative complications and prognostic factors for refractive change. We observed a progressive and significant mean refractive myopic shift of −0.80 D at 12 months after surgery. In phakic eyes, the mean myopic refractive shifts progressed significantly by −0.46 D at 3 months after surgery (P=0.003), by −0.52 D at 6 months (P=0.012), and by −1.31 D at 12 months (P < 0.001). In the pseudophakic eyes, we found no significant refraction progression at any of the postsurgery follow-up visits. Our multivariable analyses showed that lens nuclear color grade change was a significant prognostic factor for refractive myopic progression (P < 0.001). Trabeculectomy causes refractive myopic progression in phakic eyes. Nuclear sclerotic cataract progression is associated with refractive myopic shift after trabeculectomy. This trail is registered with UMIN000007813.

Randomised Clinical Trial for Postoperative Complications after Ex-PRESS Implantation versus Trabeculectomy with 2-Year Follow-Up

We compared complications between Ex-PRESS implantation and trabeculectomy for 2 years after surgery. Sixty-four open-angle glaucoma eyes were randomly assigned to treatment with trabeculectomy (n = 32) or Ex-PRESS implantation (n = 32). The primary outcomes were postoperative complications, including reduction of the endothelial cell density (ECD) of the cornea, cataract progression and the frequency of other late postoperative complications. The Ex-PRESS group had significantly greater reduction of postoperative corneal ECD than the trabeculectomy group did at 2 years after surgery (P = 0.026). Among the corneal areas measured using specular microscopy, the superior area, where the Ex-PRESS tube was inserted, had significantly more severe corneal ECD reduction than the inferior area after 2 years (-17.6% in superior area and -11.7% in inferior area, P = 0.04). More cataract progression occurred in the trabeculectomy group than in the Ex-PRESS group (P = 0.04). Twelve eyes (37.5%) in the trabeculectomy group and 4 eyes (12.5%) in the Ex-PRESS group underwent cataract surgery (P = 0.019). The total number of other postoperative complications between 3 months and 2 years was significantly higher in the trabeculectomy group than in the Ex-PRESS group (P = 0.02). Although Ex-PRESS implantation might be associated with an increased rate of corneal endothelial cell loss compared with trabeculectomy, it is beneficial for preventing cataract progression after filtering surgery.

Glaucoma treatment trends: a review

Glaucoma is one of the most common causes of blindness worldwide, and its prevalence is increasing. The aim of the present review is to describe the current medical and surgical treatment trends in the management of open-angle glaucoma. There has been an increase in the availability of glaucoma medications and the use of laser trabeculoplasty over the past decade, with a subsequent decrease in invasive incisional surgery. In addition, a new class of glaucoma procedures, termed microinvasive glaucoma surgery, has emerged, which aims to fill the gap between conservative medical management and more invasive surgery.

A New Ultrasound Biomicroscopic Sign seen after Deep Sclerectomy (Dolphin Head Sign)

PURPOSE

To describe a new ultrasound biomicroscopic (UBM) sign seen in patients who underwent deep sclerectomy (DS) as a surgical procedure for the management of uncontrolled primary open-angle glaucoma (POAG). The presence of this sign in ultrasound biomicroscopy is suggested to be an indicator of successful surgery. We would like to name this sign as the "dolphin head sign."

DESIGN

Prospective interventional study.

MATERIALS AND METHODS

Twenty-eight eyes of 17 patients with POAG underwent DS with intraoperative mitomycin C (MMC) 0.3% applied for 2 minutes under the superficial scleral flap. Patients were followed up for a minimum of 6 months. Ultrasound biomicroscopy was done at the third postoperative month to evaluate the surgical area in both successful and failed cases.

RESULTS

The study included 28 eyes of 17 patients. The mean age of the study group was 42.90 ± 14.37 years (20-64 years). The study included 10 females and 7 males. The mean preoperative intraocular pressure (IOP) was 24.57 ± 6.37 mm Hg (20-38 mm Hg). The mean best corrected visual acuity (BCVA) was 0.57 ± 0.3 (0.05-1.00). Complete success has been achieved in 21 eyes (75%) during the follow-up period, with a mean IOP of 12.00 ± 3.86 mm Hg (6-20 mm Hg). The dolphin head sign was demonstrated only in successful cases, whereas the unsuccessful cases failed to show the typical sign.

CONCLUSION

The presence of a "dolphin head" configuration in UBM images could be taken as an indicator of successful DS. How to cite this article: Abdelrahman AM, El Cheweikh HM, El-Fayoumi DMS, Allam RSHM. A New Ultrasound Biomicroscopic Sign seen after Deep Sclerectomy (Dolphin Head Sign). J Curr Glaucoma Pract 2016;10(2):56-59.

[Non-penetrating glaucoma surgery]

Patients at high risk of developing complications (e.g. high myopia, aphakia, advanced visual field defects) benefit from non-penetrating glaucoma surgery (NPGS). Neovascular glaucoma, traumatic glaucoma or patients with a narrow angle (a scleral spur must at least be visible) are not suitable for NPGS. The aim of deep sclerectomy (DS) is mainly external subconjunctival drainage. Modified with mitomycin C and intrascleral implants, intraocular pressure (IOP) and success of DS are comparable to trabeculectomy. Viscocanalostomy and the further development to canaloplasty aim for blebless IOP control. Viscocanalostomy has an extremely low complication profile but only a slight reduction in IOP. Canaloplasty creates much more favourable results. Combined with phacoemulsification canaloplasty appears to lower IOP comparable to phacotrabeculectomy and demonstrates a more sustainable success compared to canaloplasty alone.

Deep sclerectomy with mitomycin C in eyes with failed glaucoma surgery and pseudophakia

PURPOSE

To report outcomes of deep sclerectomy (DS) with intraoperative mitomycin C (MMC) application in eyes with previous failed glaucoma surgery (GS) and/or cataract extraction (CE).

PATIENTS AND METHODS

Single-surgeon case series of 82 eyes of 82 patients undergoing DS with MMC. The patients had previous CE with IOL and/or conjunctival GS and treated intraocular pressure (IOP) >18 mm Hg. MMC (0.2 mg/ml) was applied for 2-3 min before scleral flap dissection. Complete success was defined as IOP between 6 and 21 mm Hg or a reduction of 20% from baseline without medications. Reoperation for glaucoma or related complications, or loss of light perception vision was considered as failure.

RESULTS

Mean follow-up was 57.7 ± 22.4 months with 78% of patients completing the 3-year follow-up. Mean IOP decreased from 24.0 mm Hg (22.3-25.6, 95% confidence intervals) to 13.4 mm Hg (12.0-14.2) at 3 years after surgery (P<0.001). There was a significant decrease in the number of glaucoma medications from 2.0 ± 1 preoperatively, to 0.3 ± 0.7, 3 years after surgery. Kaplan-Meier cumulative success rates were 85.6% at 1 year, 80.0% at 2 years, and 76% at 3 years. At 3 years, IOP was maintained <19 and 15 mm Hg in 83 and 70% of eyes, respectively. Fourteen eyes (17.1%) had complications. Delayed hypotony (IOP <6 mm Hg) was the commonest complication in five eyes (6.1%).

CONCLUSION

DS with MMC appears to be a safe and effective surgical procedure for eyes with previous intraocular surgery.

Moving the goal posts definitions of success after glaucoma surgery and their effect on reported outcome

PURPOSE

To determine (1) the extent to which the definition of success of glaucoma surgery varies in the literature and (2) the degree to which the reported outcome after trabeculectomy is affected by the criteria used to define success.

DESIGN

A systematic review of the literature and application of definitions to a retrospective cohort.

PARTICIPANTS

A cohort of 100 patients who previously underwent trabeculectomy.

METHODS

A literature search was performed of PubMed using the search term trabeculectomy for a 5-year period. Studies presenting original data relating to longitudinal intraocular pressure (IOP) control after glaucoma surgery were included. The definitions of success and failure used were documented for each publication. Each IOP-related definition of success was applied to a cohort of patients who previously underwent trabeculectomy. Success rates were derived for each published definition up to 36 months after surgery.

MAIN OUTCOME MEASURES

Intraocular pressure measured by Goldmann applanation tonometry.

RESULTS

From 100 publications meeting the inclusion criteria, 92 distinct IOP-related definitions of success were identified. Using these definitions, success rates for this series of 100 trabeculectomies varied between 36.0% and 98.0% after 3 years of follow-up.

CONCLUSIONS

Over a recent 5-year period, there were nearly as many different definitions of success after glaucoma surgery as publications on the subject. The definition used markedly affects the quoted success rate after trabeculectomy, making interpretation of and comparison between published results extremely difficult. Standardization of published outcome parameters after glaucoma surgery is essential to allow meaningful comparisons between different study reports.

FINANCIAL DISCLOSURE(S)

The author(s) have no proprietary or commercial interest in any materials discussed in this article.

Nonpenetrating glaucoma surgery

Nonpenetrating glaucoma surgeries have been developed in recent years in order to improve the safety of conventional filtering procedures. The goal of nonpenetrating filtering procedures is to reduce intraocular pressure by enhancing the natural aqueous outflow channels, while reducing outflow resistance located in the inner wall of the Schlemm's canal and the juxtacanalicular trabecular meshwork. In the last few years viscocanalostomy and deep sclerectomy with external trabeculectomy have become the most popular nonpenetrating filtering procedures. Both involve removal of a deep scleral flap, the external wall of Schlemm's canal and corneal stroma behind the anterior trabeculum and Descemet's membrane, thus creating an intrascleral space. The aqueous humour leaves the anterior chamber through the intact trabeculo-Descemet's membrane into the scleral space, from where it will egress into different pathways. The technique is associated with a long learning curve. Published clinical trials comparing nonpenetrating glaucoma surgery to full-thickness trabeculectomy have a consensus on the superior safety profile of nonpenetrating glaucoma surgery but are not in agreement when it comes to efficacy, where conflicting results have been found. This article reviews the nonpenetrating surgical techniques, mechanisms of action, indications, contraindications, complications, and results.

Nonpenetrating glaucoma surgery: a critical evaluation

PURPOSE OF REVIEW

Nonpenetrating glaucoma surgery is popular in a number of countries because of its perceived superior safety profile to mitomycin-C trabeculectomy. This article critically evaluates recently published literature relating to nonpenetrating glaucoma surgery.

RECENT FINDINGS

Recent modifications in nonpenetrating glaucoma surgery, including the use of implants, augmentation with antiproliferatives, and use of laser goniopuncture, appear to result in improved intraocular pressure control. Comparative studies suggest a better safety profile with nonpenetrating glaucoma surgery but higher long-term intraocular pressure than after trabeculectomy. Despite this perception, a difference in intraocular pressure control between mitomycin-C trabeculectomy and nonpenetrating glaucoma surgery, when the most recent modification has been incorporated, has not been demonstrated conclusively in randomized trials conducted over sufficiently long periods to be clinically important.

SUMMARY

Nonpenetrating glaucoma surgery continues to evolve. Intraocular pressure-lowering efficacy seems to have improved with recent modifications in technique but the degree and longevity of intraocular pressure-lowering in comparison with trabeculectomy are still uncertain.