Efficacy of Trabeculectomy Combined With Limited Deep Sclerectomy Versus Trabeculectomy Alone: A Randomized-controlled Trial

PRCIS

The addition of limited deep sclerectomy (LDS) to conventional trabeculectomy increases the success rate, especially in pseudophakic eyes.

PURPOSE

This study aimed to evaluate the efficacy of LDS in enhancing the intraocular pressure (IOP)-lowering outcomes of trabeculectomy.

DESIGN

This was a parallel-arm, single-masked, randomized-controlled trial.

METHODS

A total of 68 patients (68 eyes) with moderate to advanced primary open-angle glaucoma or primary angle-closure glaucoma with pseudophakia were recruited at a tertiary eye care center in Northern India and randomized into 2 groups. Thirty-five eyes in group 1 were subjected to trabeculectomy alone and 33 eyes in group 2 were subjected to trabeculectomy with LDS. All cases were supplemented with low-dose subconjunctival mitomycin-C (0.1 mg/mL for 1 min) in both groups. The primary outcome measure was IOP, and success rates were calculated for IOP ≤18/15/12 and ≥5 mm Hg. The secondary outcome measures included evaluation of bleb morphology, presence of an intrascleral aqueous lake, and supraciliary flow on ultrasound biomicroscopy.

RESULTS

The mean postoperative IOP at 12 months was 13.4±1.83 mm Hg in group 1 and 12.5±1.67 mm Hg in group 2 (P=0.04). For IOP cutoff ≤15 mm Hg, absolute success was noted in 11 (31.4%) and 22 eyes (66.6%) in groups 1 and 2, respectively (P=0.004). At 12 months, the intrascleral lake was detected in 2 (6%) eyes in group 1 and in 9 (29%) eyes in group 2 (P=0.02). Supraciliary flow was detected in 2 eyes (6.2%) in group 2 and none in group 1 at 12 months (P=0.02). In the Cox proportional hazard model, trabeculectomy with LDS was associated with a lower rate of failure (hazard ratio: 0.32, 95% confidence interval: 0.13-0.75, P=0.009).

CONCLUSION

The addition of LDS to trabeculectomy led to lower mean IOP and higher success rates at 12 months, compared with trabeculectomy alone.

Kynurenic Acid Accelerates Healing of Corneal Epithelium In Vitro and In Vivo

Kynurenic acid (KYNA) is an endogenous compound with a multidirectional effect. It possesses antiapoptotic, anti-inflammatory, and antioxidative properties that may be beneficial in the treatment of corneal injuries. Moreover, KYNA has been used successfully to improve the healing outcome of skin wounds. The aim of the present study is to evaluate the effects of KYNA on corneal and conjunctival cells in vitro and the re-epithelization of corneal erosion in rabbits in vivo. Normal human corneal epithelial cell (10.014 pRSV-T) and conjunctival epithelial cell (HC0597) lines were used. Cellular metabolism, cell viability, transwell migration, and the secretion of IL-1β, IL-6, and IL-10 were determined. In rabbits, after corneal de-epithelization, eye drops containing 0.002% and 1% KYNA were applied five times a day until full recovery. KYNA decreased metabolism but did not affect the proliferation of the corneal epithelium. It decreased both the metabolism and proliferation of conjunctival epithelium. KYNA enhanced the migration of corneal but not conjunctival epithelial cells. KYNA reduced the secretion of IL-1β and IL-6 from the corneal epithelium, leaving IL-10 secretion unaffected. The release of all studied cytokines from the conjunctival epithelium exposed to KYNA was unchanged. KYNA at higher concentration accelerated the healing of the corneal epithelium. These favorable properties of KYNA suggest that KYNA containing topical pharmaceutical products can be used in the treatment of ocular surface diseases.

Novel Drug Delivery Systems Fighting Glaucoma: Formulation Obstacles and Solutions

Glaucoma is considered to be one of the biggest health problems in the world. It is the main cause of preventable blindness due to its asymptomatic nature in the early stages on the one hand and patients' non-adherence on the other. There are several approaches in glaucoma treatment, whereby this has to be individually designed for each patient. The first-line treatment is medication therapy. However, taking into account numerous disadvantages of conventional ophthalmic dosage forms, intensive work has been carried out on the development of novel drug delivery systems for glaucoma. This review aims to provide an overview of formulation solutions and strategies in the development of in situ gel systems, nanosystems, ocular inserts, contact lenses, collagen corneal shields, ocular implants, microneedles, and iontophoretic devices. The results of studies confirming the effectiveness of the aforementioned drug delivery systems were also briefly presented.

Effective treatment of a normal-tension glaucoma patient with bilateral ab externo XEN Gel Stent implantation

Purpose

To provide the first report of effective use of bilateral XEN Gel Stent implantation using an ab externo open-conjunctival approach designed to improve bleb function and meet the uniquely low intraocular pressure requirements of a Japanese patient with normal-tension glaucoma refractory to topical medical therapy.

Observations

A 54-year-old phakic Japanese woman with severe normal-tension glaucoma on maximally tolerated medical therapy of four topical agents presented with above-goal intraocular pressures and new medication intolerances. She underwent bilateral ab externo open-conjunctival XEN Gel Stent implantation with tenectomy and sub-Tenon's injection of 40μg of mitomycin-C, which resulted in reduction of intraocular pressures by 41.2 and 28.6% to 10 and 10 mmHg in the right and left eyes, respectively at the most recent visit. Postoperatively, a diffuse filtering bleb with good morphology developed in both eyes. The procedure has so far allowed for complete cessation of all four topical medications for up to eight months following surgery without any serious complications.

Conclusions

This case illustrates the potential of Xen Gel Stent implantation through an ab externo, open-conjunctival approach to be an effective, simple alternative to trabeculectomy to meet the unique low-pressure requirements of normal-tension glaucoma patients with practical and safety benefits of a micro-invasive approach.