The complications of trabeculectomy (a 20-year follow-up)

The Finnish current care guideline for open-angle glaucoma

This article is an English translation of the 4th Finnish Current Care Guideline for diagnostics, treatment and follow-up of primary open-angle glaucoma, normal-tension glaucoma and pseudoexfoliative glaucoma. This guideline is based on systematic literature reviews and expert opinions with Finland's geographical and operational healthcare environment in mind.

Hypotony in the early postoperative period after MicroShunt implantation versus trabeculectomy: A registry study

PURPOSE

A comparison of the safety and efficacy of the MicroShunt versus trabeculectomy in the early postoperative period, with a particular focus on hypotony.

METHODS

In this registry study, we evaluated 200 eyes of 200 glaucoma patients who underwent filtration surgery at Oslo University Hospital between 2017 and 2021. Of these patients, 100 had a Preserflo MicroShunt (Santen) implantation and 100 had a trabeculectomy procedure. The patients were examined per standard hospital protocol after filtration surgery. Data were extracted from the 4- and 8-week visits. We defined hypotony as intraocular pressure (IOP) < 6 mmHg.

RESULTS

The mean preoperative IOP was 20.6 ± 7.1 mmHg in the MicroShunt group and 21.6 ± 7.1 mmHg in the trabeculectomy group, and the patients used a mean of 3.0 ± 0.9 and 3.1 ± 0.9 glaucoma medications, respectively. After 8 weeks, IOP was reduced to 10.4 ± 5.4 mmHg and 11.3 ± 4.6 mmHg, respectively (p = 0.23). During the early postoperative period, hypotony was registered in 63% of the MicroShunt patients and in 21% of the patients in the trabeculectomy group (p < 0.001); and 11% and 1%, respectively, of the patients developed choroidal detachments (p < 0.003). One patient in the MicroShunt group required reoperation due to hypotony.

CONCLUSIONS

In this registry study, we found that the Preserflo MicroShunt and trabeculectomy had equally satisfactory IOP-lowering effects during the early postoperative period. In this same period, a high number of patients in the MicroShunt group developed hypotony.

Results of a modified ab-external trabeculectomy surgical technique in patients with open angle glaucoma

OBJECTIVE

Assess the safety and efficacy of a Modified Ab-externo Trabeculectomy surgical technique in controlling intraocular pressure (IOP) in open-angle glaucoma patients.

METHODS AND ANALYSIS

Patients diagnosed with primary or secondary open-angle glaucoma underwent this modified technique as the first filtering surgical treatment were included. The preoperative and final follow-up assessed IOP, hypotensive medications, the need for additional treatments, and early and late complications.

RESULTS

Forty-eight eyes of 38 patients were included. The mean age was 63.1 years (25-85 years), and the mean follow-up time was 35.3 months (range of 1147 months). The mean preoperative IOP was 25.21±3.48mmHg and 15.83±4.4mmHg by the follow-up end. Subsequent laser goniopuncture was performed on 14 eyes (29%) and needling in 4 eyes (8.4%). Complete success was achieved in 18 eyes (37.5%), qualified success in 17 (35.4%), and failed in 13 eyes (27.1%). Kaplan-Meier survival analysis shows a success rate of 81.7% at two years and 54.9% from year 4 to year 12. Multivariate analysis with generalized estimating equations (GEE) shows younger age as the main predictor for failure. Two eyes had choroidal detachment, three eyes progressed to cataracts that needed surgery, and five eyes had early bleb leaks.

CONCLUSIONS

This proposed technique is an effective surgical procedure for treating open-angle glaucoma with effective long-term IOP control and a low incidence of surgical complications and could be used in selected complex cases based on these results.

Changes in intra-ocular pressure, ocular pulse amplitude and choroidal thickness after trabeculectomy

CLINICAL RELEVANCE

Glaucoma is one of the most common causes of blindness. Although high intra-ocular pressure (IOP) is the most important risk factor, ocular blood flow also has an effect on prognosis.

BACKGROUND

The aim of this study was to investigate the IOP, ocular pulse amplitude (OPA) and choroidal thickness (CT) changes after trabeculectomy and to determine whether trabeculectomy has an effect on ocular blood flow.

METHODS

This retrospective, comparative case series was conducted with 33 eyes of 33 patients who underwent trabeculectomy due to uncontrolled glaucoma. The fellow eyes of 20 patients who were followed up with medical therapy were included as a control group. IOP and OPA were evaluated using a dynamic contour tonometer. Subfoveal choroidal thickness (SFCT) was obtained with enhanced depth imaging (EDI) mode of Spectralis-OCT.

RESULTS

The mean IOP was 21.6 ± 6.3 mmHg at baseline and 13.8 ± 0.9 mmHg after trabeculectomy (p ˂ 0.001), and the mean OPA was 4.1 ± 1.5 at baseline and 2.6 ± 1.6 mmHg after trabeculectomy (p ˂ 0.001). The mean SFCT was 292.2 ± 63.2 µm at baseline and 303.8 ± 70.4 µm after trabeculectomy (p = 0.024). The change in OPA was strongly positively correlated with the change in IOP (r = 0.597, p ˂ 0.001) and SFCT change was positively correlated with OPA change (r = 0.34, p = 0.05). There was no difference between the two groups in terms of IOP, OPA and SFCT values measured after trabeculectomy (respectively, p = 0.264, p = 0.627 and p = 0.949).

CONCLUSION

The large IOP decrease following trabeculectomy causes a decrease in OPA and choroidal thickening. On the other hand, trabeculectomy has no effect on OPA change.

The Wholesome Foods Approach to Trabeculectomy Wet Lab Training

Purpose  In an era when trabeculectomy surgeries in the United States are on the decline, ophthalmology residents may have limited opportunities to practice surgical techniques critical to success. However, key steps of trabeculectomy surgery can be introduced in a wet laboratory using a simple surgical model based on food items. Methods  A fresh lime and chicken parts with skin, purchased from a grocery store, were utilized to practice trabeculectomy surgery. The white rind of a lime was used as a surrogate for human sclera and was incised to create a trabeculectomy flap. The flap was then successfully sewn down with 10-0 nylon suture using an operating microscope. The skin of the chicken part was used to re-create a fornix-based and limbus-based conjunctival incision, which was then sutured closed using 6-0 Vicryl suture. A survey of wet laboratory participants was conducted to assess the feasibility and efficacy of this technique. Results  Survey respondents were divided into two groups, those who had performed ≥40 incisional glaucoma surgeries and those who had performed <40. Both groups rated the simulation a 4 (mode) out of 5 in terms of how well it prepared them for glaucoma surgery on a human eye and how well the materials replicated human tissue, with 1 being not at all and 5 being very well. Similarly, both groups rated ease of setup and material acquisition a 1 out of 5, 1 being not difficult at all and 5 being extremely difficult. Also, 93.5% of the survey respondents recommended implementing this training model at other teaching hospitals, and none of the respondents recommended against it. Conclusion  This trabeculectomy teaching model is inexpensive, clean, and safe, and it provides a reasonably realistic substrate for surgical practice. It does not require cadaver or animal eyes, and no fixatives are needed, thus minimizing the risk of contact with biohazardous materials. Wet laboratory materials are easy to obtain, making this a practical model for practicing glaucoma surgery in both westernized and developing countries.

Posture-induced changes in intraocular pressure after ab externo XEN45 gel-stent implantation in patients with primary open-angle glaucoma

BACKGROUND

To investigate posture-induced changes in intraocular pressure (IOP) after ab externo XEN45 Gel-Stent implantation in patients with medically uncontrolled primary open-angle glaucoma (POAG).

METHODS

This prospective study included thirty-two eyes with POAG that underwent XEN45 Gel-Stent implantation as a standalone procedure using an ab externo approach at Chonnam National University Hospital. IOP was measured sequentially in the sitting position, supine position, and lateral decubitus position (LDP) before and at 1, 2, 3, and 6 months after surgery using an iCare IC200 rebound tonometer. In the LDP, the eye with XEN45 Gel-Stent implantation was in the dependent position.

RESULTS

IOP at each position was significantly reduced after XEN45 Gel-Stent implantation. Posture-induced changes in IOP were maintained during the follow-up. The range of postural IOP changes was reduced at 1 month; however, no significant change was observed after that point compared with baseline levels.

CONCLUSIONS

A XEN45 Gel-Stent inserted using the ab externo approach can reduce IOP in various body positions, but seems to have limited effects on posture-induced changes in IOP in patients with POAG.

Postoperative Complications in the Primary Tube Versus Trabeculectomy Study During 5 Years of Follow-up

PURPOSE

To describe postoperative complications encountered in the Primary Tube Versus Trabeculectomy (PTVT) Study during 5 years of follow-up.

DESIGN

Multicenter randomized clinical trial.

PARTICIPANTS

A total of 242 eyes of 242 patients with medically uncontrolled glaucoma and no previous incisional ocular surgery, including 125 patients in the tube group and 117 patients in the trabeculectomy group.

METHODS

Patients were enrolled at 16 clinical centers and randomly assigned to treatment with a tube shunt (350-mm2 Baerveldt glaucoma implant) or trabeculectomy with mitomycin C (MMC, 0.4 mg/ml for 2 minutes).

MAIN OUTCOME MEASURES

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

RESULTS

Early postoperative complications occurred in 24 patients (19%) in the tube group and 40 patients (34%) in the trabeculectomy group (P = 0.013). Late postoperative complications developed in 27 patients (22%) in the tube group and 32 patients (27%) in the trabeculectomy group (P = 0.37). Serious complications producing vision loss and/or requiring a reoperation were observed in 3 patients (2%) in the tube group and 9 patients (8%) in the trabeculectomy group (P = 0.11). Cataract progression was seen in 65 patients (52%) in the tube group and 52 patients (44%) in the trabeculectomy group (P = 0.30). Surgical complications were not associated with a higher rate of treatment failure (P = 0.61), vision loss (P = 1.00), or cataract progression (P = 0.77) CONCLUSIONS: A large number of surgical complications were observed in the PTVT Study, but most were transient and self-limited. The incidence of early postoperative complications was higher following trabeculectomy with MMC than with tube shunt surgery. The rates of late postoperative complications, serious complications, and cataract progression were similar with both surgical procedures after 5 years of follow-up. Surgical complications did not increase the risk of treatment failure, vision loss, or cataract progression.

The surgical management of glaucoma: A review

After a long period of little change, glaucoma surgery has experienced a dramatic rise in the number of possible procedures in the last two decades. Glaucoma filtering surgeries with mitomycin C and glaucoma drainage devices remain the standard of surgical care. Other newer surgeries, some of which are minimally or microinvasive glaucoma surgeries, target existing trabecular outflow, enhance suprachoroidal outflow, create subconjunctival blebs, or reduce aqueous production. Some require the implantation of a device such as the iStent, Hydrus, Ex-PRESS, XEN and PRESERFLO, whilst others do not-Trabectome, Kahook dual blade, Ab interno canaloplasty, gonioscopy-assisted transluminal trabeculotomy, OMNI and excimer laser trabeculotomy. Others are a less destructive variation of an established procedure, such as micropulse transscleral cyclophotocoagulation, endoscopic cyclophotocoagulation and ultrasound cycloplasty. Cataract surgery alone can be a significant glaucoma operation. These older and newer glaucoma surgeries, their mechanism of action, efficacy and complications are the subject of this review.

Trabeculectomy versus Xen gel implant for the treatment of open-angle glaucoma: a 3-year retrospective analysis

Objective

To compare the two surgical techniques in terms of efficacy, safety, and postoperative management over 36 months of follow-up.

Methods

This retrospective clinical cohort study compared the outcome of trabeculectomy surgery and Xen gel implant in patients having uncontrolled glaucoma. Patients were recruited using the following inclusion criteria: uncontrolled intraocular pressure (IOP) on maximally tolerated medical therapy, healthy conjunctiva freely mobile in the superior sector, open-angle, glaucomatous visual field damage, full follow upfollow-up of at least 36 months. Thirty-four patients were submitted to trabeculectomy and 34 to Xen gel implant. We set the lower limit at 6mmHg mm Hg and the upper limit ≤12 mm Hg for criteria A, upper limit to ≤15 mm Hg for criteria B and upper limit ≤18 mm Hg for criteria C. Criteria for success have been characterizedcharacterised according to whether or not this has been achieved without (complete success) or with IOP -lowering medications (qualified success).

Results

For all survival curves, trabeculectomy was superior to Xen gel implant. When considering complete success, the log-rank test for criteria A was statistically significant (pp=0.006), marginally significant for criteria B (pp=0.065) and not significant for criteria C (pp=0.23). When qualified success was considered, trabeculectomy was superior to Xen gel for criteria A, B, and C (pp=0.012, pp=0.033 and pp=0.025, respectively). Higher number of post-operative flat chamber and bleb leakage was observed in the trabeculectomy group.

Conclusion

Xen gel implant techniques offer a better safety profile but a lower IOP reduction compared to compared with the gold -standard technique.

Pressure restoration and visual recovery time in hypotony after trabeculectomy

OBJECTIVES

To asses the course of intraocular pressure (IOP) restoration and visual acuity (VA) recovery in eyes with hypotony after trabeculectomy.

METHODS

Medical charts of patients undergoing trabeculectomy between January 2017 and June 2019 were reviewed. Cases with hypotony (IOP < 5 mmHg) due to over-filtration in the early postoperative period were assessed retrospectively. Primary outcome measures included change in IOP and VA in the postoperative period and percentage of eyes with hypotony on each follow-up.

RESULTS

Thirty-five eyes of 31 patients (23 male, 8 female) were included. The mean follow-up was 18.3 ± 6.9 months. The mean IOP was 3.0 ± 3.2, 9.2 ± 6.2, 9.4 ± 5.6, 9.4 ± 4.0, 10.9 ± 3.6 and 10.2 ± 3.3 mmHg at week 1, months 1, 3, 6, 12 and last follow-up, respectively. Out of 35 hypotonic eyes, 8 (22.8%) had prolonged hypotony at month 1, 4 (11.4%) at month 3, 1 (2.9%) at month 6. The decrease in VA continued to be significant at months 1 and 3 (p = 0.015, p = 0.036, respectively) and returned to baseline after the sixth month (p > 0.524).

CONCLUSIONS

In eyes with early hypotony after trabeculectomy while low IOP recovers at first month, it takes longer for the visual restoration. The postoperative month 1 appears to be decisive for recovery of hypotony.

Atypical associations of viral anterior uveitis with glaucoma-a series of challenging scenarios with review of literature

PURPOSE

To report unusual associations, atypical clinical presentations, and outcomes of tailored treatment of viral uveitis and glaucoma.

METHODS

Patients diagnosed with viral uveitis with associated glaucoma, seen at a tertiary eye care center between 2013 and 2020, were screened. Twenty-four patients with unclassified or atypical clinical presentations of viral uveitis, atypical clinical course, or with diagnostic challenges and associated glaucoma, were included. Patients with classical features of viral anterior or posterior uveitis, other forms of autoimmune/infectious/traumatic uveitis, were excluded.

RESULTS

Viral re-activation causing recurrent choroidals after glaucoma filtering surgery responsive to systemic antiviral therapy, massive pigment dusting/plume as a presenting feature, multiple progressive focal anterior synechiae similar to iridocorneoendothelial (ICE) syndrome, were seen in this cohort of unusual viral uveitis in glaucoma. A high index of suspicion helped diagnose a viral etiology in cases with high intraocular pressure (IOP) after uneventful Ahmed glaucoma valve surgery (AGV) or post-YAG capsulotomy laser, presumed Posner-Schlossman syndrome with multiple recurrences or presumed steroid glaucoma. All patients responded well with anti-viral and tailored concomitant steroids, anti-glaucoma therapy with loss of visual acuity seen in one eye developing optic atrophy.

CONCLUSIONS

Uncommon clinical presentations or associations of viral uveitis in glaucoma should be kept in mind. A high index of suspicion and tailored prompt treatment may ensure good outcomes preventing further visual morbidity in glaucoma.

Factors Associated With Unqualified Success After Trabecular Bypass Surgery: A Case-control Study

PRECIS

An older age, a low number of baseline glaucoma medications, an early glaucoma stage, lower intraocular pressure (IOP) values during the first postoperative month, and combined surgery are possible predictors of unqualified success after a trabecular by-pass microinvasive glaucoma surgery (MIGS) procedure.

PURPOSE

The purpose of this study was to identify the potential predictors of unqualified success (IOP<18 mm Hg with no glaucoma medication) after trabecular by-pass MIGS.

MATERIALS AND METHODS

We designed a case-control study using logistic regression modeling that included all trabecular by-pass surgeries with at least 3 months of follow-up, performed at a single center from June 2017 to December 2019. Eyes that achieved an endpoint of unqualified success (dependent variable) were considered cases. All other eyes were used as the controls. Cases and controls were paired by sex and postoperative time. We tested the following independent variables: age, race, laterality (right eye or left eye), glaucoma stage, type of surgery (combined or stand-alone), type of trabecular bypass, intraoperative complications, baseline number of medications, baseline IOP, and postoperative IOP on days 1, 15, and 30. Additional analysis using IOP <15 mm Hg as a threshold and including eyes with at least 12 months of follow-up were performed.

RESULTS

One hundred ninety-four eyes were included in the analysis. We observed complete success in 56.7% of eyes. The mean follow-up time for the entire population was 12.3±6.8 months. All variables were considered in the first step of the modeling process; however, only age, day-15 IOP, day-30 IOP, baseline number of medications, glaucoma stage, and type of surgery remained until the completion of our model, with adequate significance (P<0.05). The additional analysis confirmed our results.

CONCLUSION

We identified that an older age, a low number of baseline glaucoma medications, an early glaucoma stage, lower IOP values during the first postoperative month, and combined surgery were associated with a higher chance of unqualified success at 12 months after a trabecular by-pass MIGS procedure.

CO2 Laser-Assisted Deep Sclerectomy Surgery Compared with Trabeculectomy in Primary Open-Angle Glaucoma: Two-Year Results

Purpose

To compare the effectiveness and safety of carbon dioxide (CO₂) laser-assisted deep sclerectomy surgery (CLASS) and trabeculectomy (Trab) for treatment of primary open-angle glaucoma (POAG).

Methods

In this retrospective and comparative study, 77 eyes of 62 patients with POAG were studied and divided into the CLASS and Trab groups. The best-corrected visual acuity (BCVA), intraocular pressure (IOP), number of medications, surgical success rate, and complications were analyzed.

Results

The mean follow-up periods were 27.89 ± 2.94 months and 26.11 ± 2.06 months in the CLASS and Trab groups, respectively. 30 eyes (24 patients) underwent CLASS and 47 eyes (38 patients) underwent Trab. The BCVA in the CLASS and Trab groups was recovered to baseline at postoperative 1 week and 1 month, respectively. At last follow-up visits, a remarkable reduction in the IOP and number of medications was observed in both groups, and no significant difference was found in those between the two groups. The complete success rates were 51.7% and 47.7% in postoperative 24 months in the CLASS and Trab groups, respectively (P > 0.05). There were higher rates of delayed anterior chamber formation (21.3%) and thin-wall filtrating blebs (10.6%) in the Trab group. Meanwhile, the peripheral anterior synechiae were only observed in the CLASS group, and the ratio was 30%.

Conclusions

CLASS is an effective and safe treatment modality for POAG, with fewer filtering bleb-related complications and quicker visual recovery in the early postoperative stage than trabeculectomy. The efficacy of lowering intraocular pressure was similar for both procedures.

Impact of early and delayed Nd:YAG laser goniopuncture on results of deep sclerectomy (5-years follow up period)

Purpose:

To report on impact of Nd:YAG laser goniopuncture (LGP) timing on hypotensive efficacy of deep sclerectomy (DS) for open-angle glaucoma (OAG) patients.

Methods:

228 patients who underwent DS followed by Nd:YAG LGP between January 2010 and December 2013, (follow up – 5 years) were enrolled into a single-center, retrospective, non-randomized, consecutive study. Subjects were divided into two groups (1 – delayed LGP, n = 116; 2 – early LGP, n = 112). Demographic variables, preoperative glaucoma medications, preceding surgeries and glaucoma severity were analyzed. Intraoperative and postoperative complications, intraocular pressure (IOP), ultrasound biomicroscopy (UBM) values were recorded. Success rate was analyzed using Kaplan-Meier curve. UBM data were the criteria for early or delayed LGP.

Results:

LGP was performed 3.46 ± 1.9 (1.5–6.7) months after DS in group 1, 1.12 ± 0.08 (0.9–1.5) months in group 2 ( p = 0.0001). Mean IOP before LGP in group 1 was 18.5 ± 4.7 (11.2–22.9) mm Hg; 15.7 ± 4.1 (9.1–18.5) mm Hg in group 2 ( p = 0.001). Choroidal effusion occurred in 8.6% of group 1 and 3.5% of group 2 ( p = 0.0001). Postoperative IOP: 15.6 ± 4.6 (group 1) and 15.7 ± 4.3 mm Hg (group 2) at 12 months ( p = 0.98), 16.7 ± 4.3 and 14.9 ± 1.6 mm Hg at 24 months ( p = 0.004), 16.8 ± 3.9 and 14.5 ± 3.2 mm Hg at 60 months, respectively ( p = 0.0001). Complete success rates: 68.07% and 92.59% at 12 months, 40.7% and 75.8% at 24 months, 15.2% and 48.93% at 36, 48, 60 months in groups respectively ( p = 0.0001).

Conclusion:

Early LGP after DS excludes TDM influence on further formation of intrascleral canal cavity and outflow pathways demonstrating pronounced hypotensive success in a long-term follow-up.

Suppression of the TGF-β pathway by a macrolide antibiotic decreases fibrotic responses by ocular fibroblasts in vitro

To elucidate and to inhibit post-surgical fibrotic processes after trabeculectomy in glaucoma therapy, we measured gene expression in a fibrotic cell culture model, based on transforming growth factor TGF-β induction in primary human tenon fibroblasts (hTFs), and used Connectivity Map (CMap) data for drug repositioning. We found that specific molecular mechanisms behind fibrosis are the upregulation of actins, the downregulation of CD34, and the upregulation of inflammatory cytokines such as IL6, IL11 and BMP6. The macrolide antibiotic Josamycin (JM) reverses these molecular mechanisms according to data from the CMap, and we thus tested JM as an inhibitor of fibrosis. JM was first tested for its toxic effects on hTFs, where it showed no influence on cell viability, but inhibited hTF proliferation in a concentration-dependent manner. We then demonstrated that JM suppresses the synthesis of extracellular matrix (ECM) components. In hTFs stimulated with TGF-β1, JM specifically inhibited α-smooth muslce actin expression, suggesting that it inhibits the transformation of fibroblasts into fibrotic myofibroblasts. In addition, a decrease of components of the ECM such as fibronectin, which is involved in in vivo scarring, was observed. We conclude that JM may be a promising candidate for the treatment of fibrosis after glaucoma filtration surgery or drainage device implantation in vivo.

Nonpenetrating Deep Sclerectomy for Progressive Glaucoma: Long-term (5-year) Follow-up of Intraocular Pressure Control and Visual Field Survival

Purpose

To monitor 5-year outcomes of nonpenetrating deep sclerectomy (NPDS) with mitomycin C (MMC) in a new consecutive patient cohort.

Materials and methods

All eyes undergoing NPDS surgery between 1/08 and 6/12 were monitored for intraocular pressure (IOP), number of antiglaucoma medications (meds), and visual field indices [mean deviation (MD) and corrected pattern standard deviation (CPSD)], relative to the preoperative baseline using the two-tailed paired Student's t test.

Results

Of 106 eyes undergoing NPDS with MMC, mean IOP was 19.7 ± 0.5 [sem] mm Hg preoperatively, 11.9 ± 0.5 at 3 months, 12.5 ± 0.6 at 6 months, 12.4 ± 0.5 at 12 months, 12.6 ± 0.6 at 18 months, 11.1 ± 0.6 at 2 years, 11.8 ± 0.5 at 2.5 years, 11.0 ± 0.5 at 3 years, 11.7 ± 0.5 at 3.5 years, 10.7 ± 0.7 at 4 years, 11.6 ± 0.5 at 4.5 years, and 12.4 ± 0.7 at 5 years (average IOP reduction of 7.8 mm Hg or 37%; p < 10⁻⁶) at 5 years. About 92% of eyes had stable IOP ≥5 and ≤21 mm Hg at 5 years. Mean preoperative meds 2.7 ± 0.1 was reduced to 0.40 ±0.09 at 3 months, 0.51 ± 0.1 at 6 months, 0.38 ± 0.08 at 12 months, 0.49 ± 0.09 at 18 months, 0.41 ± 0.09 at 2 years, 0.39 ± 0.09 at 2.5 years, 0.49 ± 0.1 at 3 years, 0.58 ± 0.1 at 3.5 years, 0.49 ± 0.1 at 4 years, 0.64 ± 0.1 at 4.5 years, and 0.52 ± 0.1 at 5 years, corresponding to mean reduction of 2.2 meds (81%; p < 10⁻²²) at 5 years. Mean deviation and CPSD were stable relative to baseline at all time intervals (R = 0.83–0.94; p < 0.0001).

Conclusion

With appropriate postoperative management, eyes undergoing NPDS can maintain excellent IOP control with minimal medication use and maintain very stable visual fields over an extended time frame.

How to cite this article

Slagle G, Groth SL, Montelongo M, et al. Nonpenetrating Deep Sclerectomy for Progressive Glaucoma: Long-term (5-year) Follow-up of Intraocular Pressure Control and Visual Field Survival. J Curr Glaucoma Pract 2020;14(1):3–9.

[Results of surgical treatment of glaucoma using sinustrabeculectomy modified for drainage of anterior chamber and suprachoroidal space by autosclera]

In order to achieve a persistent hypotensive effect in primary open-angle glaucoma, a modification of the sinustrabeculectomy operation - modified sinustrabeculectomy with basal iridectomy combined with deep sclerectomy involving drainage of the anterior chamber and suprachoroidal space have been developed at the Department of Eye Diseases of the People's Friendship University of Russia.

PURPOSE

Development of a new method of surgical treatment of primary open-angle glaucoma based on sinustrabeculectomy with basal iridectomy in combination with deep sclerectomy involving drainage of the anterior chamber and suprachoroidal space by autosclera, and evaluation of the surgical outcomes.

MATERIAL AND METHODS

The study analyses the results of surgical treatment of 19 patients (19 eyes) with glaucoma, who underwent sinustrabeculectomy with basal iridectomy in combination with deep sclerectomy and drainage of the anterior chamber and suprachoroidal space.

RESULTS

The level of intraocular pressure (IOP) on the first day after surgery decreased from 14 mm Hg to 17.5 mm Hg in the late postoperative period (after 12 months), IOP of 18 patients had normalized and stabilized (IOP averaged 17.0±1.8 mm Hg); in 1 case there was an increase in IOP level, for which hypotensive therapy was prescribed (β-blockers).

CONCLUSION

Modified sinustrabeculectomy with basal iridectomy in combination with deep sclerectomy and drainage of the anterior chamber and suprachoroidal space by autosclera helps achieve a persistent hypotensive effect and does not require the use of donor material.

Combined iStent® Inject Trabecular Micro-Bypass and Phacoemulsification in Australian Patients with Open-Angle Glaucoma

Purpose

This retrospective audit aimed to evaluate the impact of combined iStent^®Inject (iSI) and phacoemulsification on medication number in Australians with open-angle glaucoma. Secondary outcomes included intraocular pressure (IOP), best-corrected visual acuity, refraction and visual fields.

Patients and Methods

Patients with glaucoma that received combined iSI and phacoemulsification by the same surgeon between 1 February 2016 and 1 February 2018 were audited for postoperative medication number, pressures after 1 day, 1 week, 4 weeks and 6, 12, 18 and 24 months, visual acuity, refraction and visual fields. These parameters were compared to baseline levels and with those from a separate cohort of patients without glaucoma that received standalone phacoemulsification.

Results

Forty-one patients (63 eyes) received the combined procedure. Thirty-four patients (59 eyes) received standalone phacoemulsification. Four weeks after receiving combined iSI and phacoemulsification the mean medication number was significantly reduced by 1.3 (p < 0.001) for those on medication at baseline and by 0.5 (p = 0.002) overall. Mean IOP was significantly reduced from baseline after 6 months (–16%; p = 0.012; n = 35) and 12 months (–29%; p = 0.004; n = 16). Patients receiving standalone phacoemulsification had short-term reductions in IOP at 4 weeks (–8%; p < 0.001; n = 57) and 6 months (–16%; p < 0.001; n = 32). These patients without glaucoma had lower pressures overall compared to those with glaucoma that received the combined procedure (p = 0.019). There were no differences in final visual acuity or refractive outcomes between groups.

Conclusion

This audit suggests that iSI and phacoemulsification are at least as effective in controlling IOP as medical therapy. It may have an important role in reducing the medication burden in Australians with cataract and glaucoma. This study is one of the first to confirm refractive stability in concomitant iSI and phacoemulsification.

SUBCONJUNCTIVAL FRAGMENTATION OF A PREVIOUSLY EFFICIENT XEN GEL STENT IMPLANTATION AND SUCCESSFUL BLEB FORMATION: A CASE REPORT

The XEN gel stent is one of the available minimally invasive glaucoma surgery devices, a new generation implant, which is designed to reduce intraocular pressure in patients with primary open angle glaucoma if past medical treatments have failed. This report presents a case of subconjunctival fragmentation of the XEN gel stent after a three-month follow-up of successful XEN gel implantation. A 70-year-old male patient was treated for primary open angle glaucoma. He underwent successful phacoemulsification and intraocular lens implantation two years before. Due to medical therapy failure in controlling glaucoma, XEN gel stent implantation was suggested to the patient. The implant was successfully placed in both eyes, and extended bleb and drainage aqueous humor from the anterior chamber to the subconjunctival space was obtained. Three months after the surgery, at a regular follow-up visit, three fragments of the subconjunctival part of the XEN gel implant were found in his left eye. Neither serious complications nor intraocular pressure increase were detected. A new potential complication of the XEN gel implant is described.

[Trabeculectomy with Ologen® implant and bevacizumab]

BACKGROUND

Trabeculectomy is the most frequent form of glaucoma surgery. Despite the intraoperative use of antimetabolites, such as mitomycin C (MMC) postoperative scarring reactions can cause surgical failure. The subconjunctival placement of an Ologen® implant can avoid wound scarring. The additional application of bevacizumab should reduce angiogenesis and thereby scarring reactions and improve the surgical success rate.

METHODS

This was a retrospective single center study of patients with glaucoma after trabeculectomy with MMC. The operation was carried out either without an Ologen® implant (group 1), or with an Ologen® implant as an bevacizumab depot (group 2) or with an Ologen® implant and intrachamber injection of bevacizumab (group 3). The follow-up postoperative observation of intraocular pressure (IOP), complications, subsequent interventions and antiglaucoma treatment was performed for 12 months.

RESULTS

There were no significant differences between the groups with respect to IOP, complications, subsequent interventions and postoperative antiglaucoma treatment. The highest success rate (IOP after 12 months ≤15 mm Hg without treatment) was in group 1 (77.5%), followed by group 2 with 63.6% and group 3 with 57.1% (p = 0.34, χ²-test).

CONCLUSION

The highest success rate was achieved in group 1 with MMC but without an Ologen® implant or bevacizumab. In this study the additional use of Ologen® implants and bevacizumab in trabeculectomy was found to be a safe operation method but did not provide any additional benefits.

Midterm outcome of mitomycin C augmented trabeculectomy in open angle glaucoma versus angle closure glaucoma

Purpose

The purpose of this study is to evaluate the efficacy and safety of Trabeculectomy with Mitomycin C in Open angle glaucoma versus Angle closure glaucoma.

Methods

The medical records of patients who underwent Trabeculectomy with Mitomycin C were reviewed and followed for three years, divided into two groups: group 1: Open Angle Glaucoma (n = 41) and group 2: Angle Closure Glaucoma (n = 67). Success criterion was measured as Intraocular Pressure ≤21 mmHg with (qualified) or without (complete) use of Antiglaucoma medications.

Results

A total number of 108 eyes of 137 patients were undertaken. Mean preoperative Intraocular pressure in group 1 was 31.4 ± 10.5 mmHg and in group 2 was 33.1 ± 9.4, which reduced to 10.5 ± 3.4, 10.5 ± 2.6, 11.6 ± 3.6, 11.0 ± 2.7, 11.0 ± 2.7 in group 1 and 10.9 ± 2.8, 12.0 ± 3.8, 12.8 ± 4.9, 12.4 ± 3.9, 12.4 ± 3.7 in group 2 with P value = 0.566, 0.032, 0.168, 0.049, 0.049 at three, six months, one, two, three years, respectively, with P < 0.001 at each visit. The number of Antiglaucoma medications was reduced from 0.75 ± 0.89 to 0.43 ± 0.55 at 3 yrs (P = 0.002). At 36 months follow-up, overall, 50.0% and 48.2% of eyes achieved complete and qualified success, respectively. Sub-group analysis showed that the success rate was higher in group 1 (68.3%) compared to group 2 (55.2%). Overall, complications such as hypotony (1.8%), choroidal detachment (2.8%), encapsulated bleb (2.8%), and bleb leakage (1.8%) were encountered.

Conclusion

Primary Trabeculectomy with Mitomycin C is a safe and effective means of controlling Intraocular Pressure in both groups with good success and low rates of sight-threatening complications.

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.

One-Year Results of Stab Incision Glaucoma Surgery and Radiofrequency-Assisted Stab Incision in Management of Open-Angle Glaucoma

PURPOSE

The aim of the study is to evaluate the surgical outcome of stab incision glaucoma surgery (SIGS) and compare it with radiofrequency-assisted stab incision in the treatment of uncontrolled open-angle glaucoma.

PATIENTS AND METHODS

A prospective, interventional study included 50 eyes who were assigned into two equal groups: Group A underwent stab incision procedure with preoperative subconjunctival (SC) mitomycin-C (MMC) and Group B underwent radiofrequency-assisted technique without MMC. Intraoperative and postoperative complications, visual acuity, intraocular pressure (IOP), and bleb status were evaluated up to 12 months.

RESULTS

Mean preoperative IOP in Group A was 26.96 ± 2.42 reduced to 13.43 ± 2.31 while in Group B was 27.20 ± 3.57 reduced to 15.48 ± 3.68 mmHg (P < 0.001) with a mean reduction of 50.61% ± 8.42% and 43.56% ± 12.83%, 12 months postoperatively in Groups A and B, respectively. Non-basal peripheral iridectomy was the most encountered intraoperative complication in 8 eyes (32%) and 9 eyes (36%) and hypotony was the most reported postoperative complication in 5 eyes (20%) and 9 eyes (36%) in Groups A and B, respectively. Flat bleb area had been reported at the end of follow-up time in 3 eyes (13%) and 7 eyes (30%) in Groups A and B, respectively. Complete success rate was 52.2% and 28.6% while qualified success rate was 28.8% and 42.9% in Groups A and B, respectively.

CONCLUSION

SIGS with SC MMC is an effective and safe procedure in IOP lowering, while radiofrequency-assisted stab incision had high incidence of subconjunctival scarring and ostium closure.

XEN® Gel Stent in Medically Refractory Open-Angle Glaucoma: Results and Observations After One Year of Use in the United States

Introduction

The purpose of this study was to evaluate intraocular pressure (IOP) lowering and safety of XEN^® stent in medically refractory, progressive, open-angle glaucoma (OAG).

Methods

Forty-seven eyes of 42 patients were treated with XEN^® stent alone or combined with phacoemulsification.

Results

Mean IOP decreased from 22.34 ± 7.34 mmHg to 12.91 ± 4.21, 12.95 ± 4.36, 13.49 ± 3.91, and 13.36 ± 3.63 mmHg at 1, 3, 6, and 12 months (95% confidence interval [CI] [20.24, 24.44], [11.71, 14.12], [11.63, 14.27], [12.36, 14.62], and [12.10, 14.62]), respectively. Mean number of medications decreased from 2.96 ± 1.20 (95% CI [2.62, 3.30]) at baseline to 0.75 ± 1.27 (95% CI [0.31, 1.19]) at 1 year. At 1 year (n = 32), complete success was achieved in 68.8% (n = 22/32) (i.e., IOP reduction ≥ 20% and IOP < 18 mmHg without medication or any secondary glaucoma intervention). Qualified success was achieved in 90.6% (n = 29/32) (i.e., IOP reduction of ≥ 20% and IOP < 18 mmHg with and without medication or any secondary glaucoma intervention). Eleven eyes had not yet reached 12 months. Two patients (three eyes) died before 1 year; one patient (one eye) was lost to follow up. Adverse events: localized choroidal hemorrhage in one eye; hypotony (IOP < 6 mmHg) at day 1 in 10 eyes, with full resolution by 2 weeks. No persistent hypotony or maculopathy occurred. Stent erosion with removal occurred in two eyes. Fourteen eyes (29.8%) underwent needling. One patient required trabeculectomy.

Conclusions

XEN^® stent is effective and relatively safe surgery for medically refractory, progressive, OAG out to 1 year. Intraocular pressure and medications were significantly reduced.

Ologen implant versus mitomycin-C for trabeculectomy: A meta-analysis

AIM

To evaluate the efficacy and safety of trabeculectomy (Trab) with mitomycin-C (MMC) versus Trab with implant.

METHODS

Studies published in different languages were retrieved by systematically searching Embase, PubMed, Cochrane library, China Biology Medicine disc, and Google Scholar from 1966 to April 2018, as well as manually examining the references of the original articles. The outcome measures of efficacy covered intraocular pressure, glaucoma medications reductions, and success rate. Safety evaluation was measured by relative ratio of complications.

RESULTS

A total of 11 studies involving 443 participants were covered in this meta-analysis. The weighted mean difference (WMD) in the percentage of intraocular pressure (IOP) reduction (IOPR%) comparing Ologen group with MMC group was -3.69 (95% CI: -6.70 to -0.68) at 1 month, -2.69 (-5.17 to -0.21) at 3 months, -3.67 (-6.09 to -1.25)at 6 months, -3.24 (-6.08 to -0.41) at 12 months, 1.24 (-9.43 to 11.90) at 24 months, and 1.10 (-10.11 to 12.31) at 60 months, which showed that there was statistically significant difference at 1,3, 6, and12 months after the surgery. A significantly higher incidence of postsurgery hypotony (0.64 (95% Cl: 0.42 to 0.98)) and suture lysis (0.30 (95% CI: 0.10-0.93)) was observed in MMC group. However, there was no significant difference in the reduction in glaucoma medications, success rate, and incidence of other complications.Trab with 0.2 mg/mL MMC presented higher rates of complete success compared with Trab with 0.4 mg/mL MMC (P = .01).

CONCLUSION

Trab with MMC was associated with a higher IOP-lowering efficacy and a higher incidence of postsurgery hypotony and suture lysis in contrast to that of Trab with Ologen.

Optimum time for angle visualization during ab interno glaucoma surgery: Before or after phacoemulsification

PURPOSE

To determine whether it is more advantageous to perform ab interno glaucoma surgeries involving the angle before or after phacoemulsification.

SETTING

University of Colorado Health Eye Center, Aurora, USA.

DESIGN

Retrospective case series.

METHODS

Video recordings were taken of eyes having phacoemulsification with or without angle surgery. From the videos, still images of the angle before and after cataract surgery were obtained. Four glaucoma physicians independently reviewed the images and were masked to whether the images presented side-by-side were captured before or after cataract surgery. The reviewers used a 5-point rating scale to assess which of the 2 presented images showed the best visualization of the angle. Patient and ocular characteristics were analyzed to determine predictive factors for better view before or after phacoemulsification.

RESULTS

Twenty side-by-side comparisons (20 eyes of 20 patients) were reviewed and rated. The mean rating of all surgeons was 2.93, nearing the "3-no difference" response. The most common response was "3-no difference" between each photograph (32.5%), followed by "4-post phacoemulsification image somewhat better" (30%), and "2-pre-phacoemulsification image somewhat better" (27.5%). No ocular characteristic, including anterior chamber depth, angle pigmentation, or cumulative dissipation energy, was found to be predictive of surgeon preference.

CONCLUSION

In combination phacoemulsification and angle-based glaucoma procedures, there appears to be no significant angle visualization difference whether the surgeon chooses to complete angle surgery before or after phacoemulsification; therefore, the decision of surgical order should rely on surgeon preference.

Comparison of the effect of mitomycin C and bevacizumab-methylcellulose mixture on combined phacoemulsification and non-penetrating deep sclerectomy surgery on the intraocular pressure (a clinical trial study)

PURPOSE

Comparison of the effect of mitomycin C (MMC) versus bevacizumab-methylcellulose mixture (BMM) on combined phacoemulsification and non-penetrating deep sclerectomy surgery on the intraocular pressure in patients with open-angle glaucoma was made.

METHODS

The current study is a controlled, randomized, double-blind clinical trial. Thirty-eight patients were enrolled, with a total of 40 eyes, and underwent a combined phacoemulsification and non-penetrating deep sclerectomy surgery from 2016 to 2017. MMC with concentration of 0.2 mg/mL for 2 min was used for 20 eyes before separating the scleral flap, and 0.3 mL of BMM (bevacizumab 1.25 mg incorporated into 2% methylcellulose) was injected subconjunctivally following surgery. The success rate of surgery was categorized as complete, relative and failure. Fisher's exact, Mann-Whitney U and Chi-square tests were employed to data analysis. A p value < 0.05 was supposed significant.

RESULTS

Patients had the same distribution in terms of age, sex, type of glaucoma and type of cataract. Patients were followed up for a mean of 6 months. The mean intraocular pressure before surgery in the MMC group was 24.85 ± 2.83 mmHg with 3.2 ± 0.523 anti-glaucoma drugs, which reached 13.75 ± 3.552 mmHg with 0.15 ± 0.489 anti-glaucoma drugs at the latest visit. The average intraocular pressure before surgery in the BMM group was 24.45 ± 2.48 mmHg with 2.9 ± 0.641 anti-glaucoma drugs, which reached 15.40 ± 3.267 mmHg with 0.25 ± 0.55 anti-glaucoma drug at the last follow-up. The intraocular pressure was notably lower in the MMC group than BMM group 6 months after surgery. There was not a significant difference from the aspect of success rate and failure rate among the two groups at the 6-month follow-up (p = 0.135).

DISCUSSION

Based on the results of this study, MMC and bevacizumab-methylcellulose both seem to be effective in the success of combined phacoemulsification and non-penetrating deep sclerectomy surgery, but MMC decreases intraocular pressure in patients at 6 months post-surgery.

[XEN-45 Gel Stent implant in glaucoma treatment]

The XEN-45 drainage implant is a hypotensive device made of hydrophilic gelatin and stabilized by glutaraldehyde. The implant is designed for modern Microinvasive Glaucoma Surgery (MIGS). Being installed ab interno, the stent drains aqueous fluid from the anterior chamber into the subconjunctival space. According to indications, XEN-45 can be used in treatment of primary open angle glaucoma, pseudoexfoliation or pigment glaucoma with uncompensated intraocular pressure amid maximum tolerated hypotensive therapy, and refractory glaucoma including cases with history of unsuccessful surgery. The implant can also be effectively used in combination with phacoemulsification. The article describes the structure and implantation process of the XEN drainage and reviews existing clinical trials on its effectiveness. The article also presents results on hypotensive efficacy of the implant, as well as characteristics and complications of postoperative management.

Low-Dosage Mitomycin C as an Adjunct to Trabeculectomy. A Prospective Controlled Study

PURPOSE

To assess the advantages and adverse effects of intraoperative low-dose Mitomycin C in filtering glaucoma surgery.

METHODS

Sixty eyes of 48 patients undergoing surgery for uncontrolled glaucoma were randomized to two groups: one underwent standard trabeculectomy, the other had trabeculectomy with intraoperative application of 0.1 mg/ml mitomycin C. Follow-up was at least one year.

RESULTS

The success rate (IOP < 18 mmHg) was 96.6% in the mitomycin C group and 73.3% in the control group. Mean IOP at one year of successful cases was 11.1 +/- 3.1 mmHg in the mitomycin C group and 16.4 +/- 6.1 mmHg in controls (p < 0.0001). Two patients in the mitomycin C group (6.6%) and six (20%) in the control group needed antiglaucomatous drugs to keep IOP below 18 mmHg.

CONCLUSIONS

Mitomycin C is a useful adjunct to glaucoma surgery. Adverse effects at the dosage used are mainly due to hypotony and are preventable with two-layer suture. Low-dose mitomycin C may be useful in standard primary trabeculectomy.

Prospective randomized controlled trial of phaco-trabectome versus phaco-trabeculectomy in patients with open angle glaucoma

OBJECTIVE

To compare the efficacy and safety of ab interno trabeculectomy with the Trabectome combined with cataract surgery (phaco-AIT) versus Trabeculectomy with mitomycin C combined with cataract surgery (phaco-Trab) in open-angle glaucoma.

METHODS

A prospective randomized controlled trial with a single surgeon and surgical center was undertaken. Patients were recruited from July 2009 to October 2014. Primary outcomes were mean intraocular pressure (IOP) at 6 months and surgical complications. Secondary outcomes were mean IOP at 12 months, achievement of target IOP, number of glaucoma medications, and rate of secondary surgery.

RESULTS

The trial was ended early before achieving our intended sample size due to difficulties in recruitment and lack of clinical equipoise over time. Nineteen patients were enrolled, 10 phaco-AIT and 9 phaco-Trab. Baseline IOP was 20.0 ± 5.3 in phaco-AIT and 23.1 ± 6.4 mm Hg in phaco-Trab (p = 0.22). IOP decreased to 17.5 ± 3.8 and 16.0 ± 6.0 mm Hg at 6 months (p = 0.54), and 16.8 ± 2.7 and 17.1 ± 5.0 mm Hg at 1 year (p = 0.57), respectively. Mean number of glaucoma medications at baseline was 1.8 ± 1.3 in phaco-AIT and 1.4 ± 1.1 in phaco-Trab (p = 0.59). Mean number of glaucoma medications decreased to 0.78 ± 1.39 and 0.38 ± 0.74 at 6 months (p = 0.68), and 0.44 ± 0.88 and 0.75 ± 0.89 at 1 year (p = 0.41), respectively. Mild and moderate complications were seen in both treatment groups, but severe complications were seen only in phaco-Trab. One secondary glaucoma procedure was required in the phaco-AIT group.

CONCLUSIONS

Phaco-AIT achieved similar IOP lowering at 6 and 12 months compared with phaco-Trab with a similar number of glaucoma medications required at 1 year, and no serious complications were identified in the Phaco-AIT group.

Comparison of 1-year outcomes after Ahmed glaucoma valve implantation with and without Ologen adjuvant

Background

Many studies have investigated the clinical benefits of Ologen for trabeculectomy. However, its benefits for Ahmed glaucoma valve (AGV) implantation have not been investigated as extensively. The aim of this study was to compare the 1-year outcomes of AGV implantation with and without Ologen adjuvant for the treatment of refractory glaucoma.

Methods

This retrospective study included a total of 20 eyes of 20 glaucoma patients, who were followed for at least 1-year after undergoing AGV implantation. In 12 eyes of 12 patients, conventional AGV (CAGV) surgery was performed, while in 8 eyes of 8 patients, Ologen-augmented AGV (OAGV) implantation was performed. The outcomes were evaluated according to intraocular pressure (IOP) and the number of IOP-lowering medications. Complete success was defined as IOP ≤ 21 mmHg without medications throughout the 1-year follow-up period, and qualified success was defined as IOP ≤ 21 mmHg with or without medications throughout the 1-year follow-up period.

Results

The rate of complete success was significantly higher in the OAGV group (50.0%) than in the CAGV group (8.3%) (p = 0.035). There were no significant differences between the two groups in terms of qualified success or incidence of the early hypertensive phase. The IOP changes were similar between the groups within 1-year postoperatively, though the number of IOP-lowering medications was significantly lower in the OAGV group during the early hypertensive phase (p = 0.031, 0.031, and 0.025 at postoperative months 1, 2, and 3, respectively). When subjects were divided into groups according to the occurrence of the early hypertensive phase, the group with early hypertensive phase was more likely to use IOP-lowering medications at postoperative 6 months and 1 year (p = 0.002 and 0.005, respectively).

Conclusions

OAGV surgery shows encouraging results for patients with refractory glaucoma, specifically with respect to the achievement of complete success and the reduction of the number of IOP-lowering medications during the early hypertensive phase. Furthermore, our results suggest that occurrence of the early hypertensive phase is predictive of which patients will require IOP-lowering medications at postoperative 6 months and 1 year.

Nonpenetrating Deep Sclerectomy: A 6-Year Retrospective Study

Purpose

Nonpenetrating trabeculectomy, also called nonpenetrating deep sclerectomy (NPDS), is a filtering surgery where the internal wall of Schlemm's canal is excised, allowing sub-conjunctival filtration without actually entering the anterior chamber. This technique was developed to minimize the complications of trabeculectomy. The authors investigated its safety and efficacy in a retrospective noncomparative study.

METHODS

A total of 258 eyes (179 patients, mean age 61.4±11.56 years) with uncontrolled open angle glaucoma with prior medical therapy were treated. NPDS with a biocompatible collagen device (157 eyes) sutured to deep scleral bed or with the use of a 5-fluorouracil sponge (90 eyes) were analyzed. The main outcome measure was postoperative intraocular pressure (IOP) with an average follow-up of 54.4±17.07 months (range 1–85). Efficacy was determined 1 month, 3 months, and every 6 months after the procedure for 6 years.

Results

Mean preoperative IOP was 24.47±5.92 mmHg. Mean postoperative IOP was 14.44±5.31 mmHg (average lowering of the IOP was 38.94±23.81%) at 1 month, 15.16±4.57 mmHg (35.73±21.35%) at 3 months, 15.87±4.24 mmHg (32.45 ±20.52%) at 6 months, 16.32±4.53 mmHg (29.96±23.69%) at 12 months, 17.12±4.45 mmHg (26.51±23.93%) at 18 months, 16.77±4.44 mmHg (28.18±21.73%) at 24 months, 16.43±4.15 mmHg (28.89±23.69%) at 30 months, 16.34±4.12 mmHg (30.05±21.61%) at 36 months, 16.16±4.01 mmHg (30.06±22.55%) at 42 months, 15.71±3.74 mmHg (32.49±19.08%) at 48 months, 15.61±3.48 mmHg (31.26±21.01%) after 5 years, and 15.81 ±3.79 mmHg (33.73±20.9%) after 6 years. YAG goniopuncture was performed in 47.3% of cases with a mean follow-up of 12±13 months. These goniopunctures were effective in lowering IOP after a long-term follow-up (24 months). Additional 5-fluorouracil injections were used in 7% of cases. Visual field (Octopus or Humphrey mean defect and corrected loss variance or loss variance) was not modified (p<0.01). Number of preoperative glaucoma medications was 2.01±0.58 and number of postoperative glaucoma medications was 0.85±0.92. Complications were peroperative microperforations in 27 eyes (10.5%), shallow anterior chamber in 2 eyes, hyphema in 2 eyes (0.8%), cataract in 5 eyes (2%), and dellen in 1 eye (0.4%). No cases of endophthalmitis or choroidal detachment were found. After surgery, 23 eyes (8.9%) required a new filtering surgical procedure, and diode laser cyclophotocoagulation was necessary in 2 eyes (0.8%). The probability success rate, defined as an IOP lower than 21 mmHg, was 66.46% (Kaplan Meier) at 60 months off all glaucoma medications and 80.32% with medical or new surgical treatment.

CONCLUSIONS

NPDS appears to be an effective and safe filtering procedure for lowering IOP and could be an alternative to trabeculectomy in open angle glaucoma with the advantage of having fewer complications.

Prospective evaluation of CO2 laser-assisted sclerectomy surgery (CLASS) with Mitomycin C

PURPOSE

Our purpose was to evaluate the clinical safety and efficacy of CO₂ laser-assisted sclerectomy surgery (CLASS) with Mitomycin C (MMC) in open angle glaucoma (OAG).

METHODS

This was a prospective, uncontrolled, interventional case series. All subjects underwent CLASS procedure by a single surgeon. After the dissection of a partial thickness scleral flap, topical MMC 0.2 mg/ml was applied to the sclera and the conjunctiva for 3 min. The CO₂ laser with a beam-manipulating system was used to ablate the scleral tissue and expose the Schlemm's canal area. Primary outcomes: intraocular pressure (IOP) change, number of IOP-lowering medicaments change. Adverse events were evaluated as secondary outcomes.

RESULTS

Twenty-one eyes of 21 patients underwent the CLASS procedure. Thirteen were primary OAG (62%), two normal pressure glaucoma (10%), three exfoliative glaucoma (14%) and three others secondary OAG. With a mean (SD) follow-up of 15.3 (5.9) months, the IOP changed from 25.4 (6.7) mmHg at baseline to 10.9 (3.4) mmHg al the last visit. Mean reduction of IOP was -14.5 mmHg (95% CI, -17.7 to -11.2, P < 0.001). The median (IQR) number of IOP-lowering medication decreased from 3 (3-3) at baseline to 1 (0-1) at the last visit (P < 0.001). Visual acuity did not change significantly. Adverse events: five eyes (24%) developed iris adhesion to the filtration area that was successfully managed with office-based procedures. In one case (5%), CLASS was converted to trabeculectomy due to intraoperative perforation of the ablated area. There was one case of hypotony maculopathy successfully treated with placement of additional transconjunctival scleral flap sutures.

CONCLUSIONS

The CLASS procedure with MMC is clinically safe and effective maintaining a large reduction in IOP and in the number of IOP-lowering medications with a mean follow-up of 15 months. Iris adhesion at the filtrating area warrants further evaluation and possibly reflects the surgeon's learning curve.

Minimally invasive combined glaucoma and cataract surgery: clinical results of the smallest ab interno gel stent

PURPOSE

To verify the efficacy in intraocular pressure (IOP) reduction and safety of the smallest gel stent (XEN 45 Gel Stent) microincisional glaucoma surgery combined with microincisional cataract surgery (MICS).

METHODS

Nonrandomized prospective clinical study. Forty-one eyes of 33 patients with open-angle glaucoma underwent a XEN 45 Gel Stent implantation combined with MICS. Treatment outcomes analyzed included: IOP, medication use, intra- and postoperative complications. At the end of the follow-up, we evaluated the complete success, defined as a postoperative IOP ≥ 6 and ≤17 mmHg without glaucoma medications and the qualified success defined as a postoperative IOP ≥ 6 and ≤17 mmHg, with glaucoma medications.

RESULTS

The mean preoperative IOP was 22.5 ± 3.7 mmHg on 2.5 ± 0.9 medication classes. After 12 months, the mean postoperative IOP was 13.1 ± 2.4 mmHg (mean IOP reduction of 41.82%) with a mean of 0.4 ± 0.8 medication classes (P < 0.05 for IOP and medications). The complete success rate was achieved in 80.4% and a qualified success in 97.5%. There were no major intra- and postoperative complications during the first year of follow-up.

CONCLUSIONS

This study demonstrated that the smaller diameter XEN 45 gel implant is statistically effective in reducing IOP and medications in glaucoma patients with a low rate of complications.

Aqueous outflow - A continuum from trabecular meshwork to episcleral veins

In glaucoma, lowered intraocular pressure (IOP) confers neuroprotection. Elevated IOP characterizes glaucoma and arises from impaired aqueous humor (AH) outflow. Increased resistance in the trabecular meshwork (TM), a filter-like structure essential to regulate AH outflow, may result in the impaired outflow. Flow through the 360° circumference of TM structures may be non-uniform, divided into high and low flow regions, termed as segmental. After flowing through the TM, AH enters Schlemm's canal (SC), which expresses both blood and lymphatic markers; AH then passes into collector channel entrances (CCE) along the SC external well. From the CCE, AH enters a deep scleral plexus (DSP) of vessels that typically run parallel to SC. From the DSP, intrascleral collector vessels run radially to the scleral surface to connect with AH containing vessels called aqueous veins to discharge AH to blood-containing episcleral veins. However, the molecular mechanisms that maintain homeostatic properties of endothelial cells along the pathways are not well understood. How these molecular events change during aging and in glaucoma pathology remain unresolved. In this review, we propose mechanistic possibilities to explain the continuum of AH outflow control, which originates at the TM and extends through collector channels to the episcleral veins.

Innovations and adaptations in trabeculectomy

PURPOSE OF REVIEW

This article examines the current literature reporting updates on trabeculectomy techniques, complications, and cost-effectiveness.

RECENT FINDINGS

Trabeculectomy continues to be the standard for glaucoma surgery when a low intraocular pressure is required. Recent publications describe technique modifications that successfully increase efficacy and lower complications. There is also an ongoing effort to define the role of trabeculectomy in the management of glaucoma from a cost and public health standpoint.

SUMMARY

The current literature continues to support the use of trabeculectomy as a method of lowering intraocular pressure in glaucoma management. Efficacy has been improved by ongoing surgical innovation, and reported complication rates are lower than those previously noted. Trabeculectomy has a favorable cost-benefit profile when compared with medical therapy or other surgical techniques. In spite of these ongoing changes, trabeculectomy appears to be decreasing in frequency in favor of newer surgeries and medications.

The Future of Glaucoma Surgery

Glaucoma surgery is ripe for innovation. In the last few years, there has been a substantial increase in the number of devices approaching commercialization. While not all that is new is necessarily good, the role of these devices in changing glaucoma surgery is equally important in terms of both success and failure. Trabeculectomy, the most commonly performed incisional filtration surgery for glaucoma, is subjective by nature and certainly has risks. As devices aim to standardize glaucoma surgery, specifically subconjunctival filtration surgery, predictability and in turn safety should theoretically improve. This may allow the glaucoma surgeon to intervene earlier in the disease process, prevent more advanced vision loss and potentially decrease the burden of medications.

Prospective Randomized Study Comparing Combined Phaco-ExPress and Phacotrabeculectomy in Open Angle Glaucoma Treatment: 12-Month Follow-Up

Purpose of the Study. To compare the efficacy and safety of phacotrabeculectomy (P-Trab) and phacoemulsification with the ExPress (P-ExPress) mini glaucoma shunt implantation. Study Plan. Prospective randomized study. Material and Methods. 85 eyes with cataract and unregulated open angle glaucoma. There were 46 eyes in the P-ExPress and 39 the P-Trab group. Intraocular pressure (IOP), the number of antiglaucoma medications, qualified and complete surgical success (defined as IOP ≤ 18.0 mmHg), visual acuity (CDVA), the number of endothelial cells, and postoperative complications and additional procedures were assessed. Results. After 12 months of observation, the average IOP in the P-Express group went from 26.4 ± 9.3 down to 17.1 ± 5 mmHg (P < 0.05) and from 27.9 ± 12.9 down to 15.9 ± 2.7 mmHg in the P-Trab group (P < 0.05). No significant differences in the amount of medications used after surgery and CDVA were discovered between the groups. In the P-ExPress group, greater loss of endothelial cells was noted (CD_loss%), compared to the P-Trab group. Conclusions. Both P-ExPress and P-Trab have comparable efficacy and similar early postoperative complication profile. The presence of additional implant (as is the case of the ExPress mini glaucoma shunt implantation) may cause progressive loss of endothelial cells.

Time Heals All Wounds: Obstacles in Glaucoma Surgery from an Asian Perspective

Glaucoma is the leading cause of irreversible blindness worldwide and is a particular burden on the Asian population. Glaucoma surgeries such as trabeculectomy and glaucoma drainage implants are routinely performed to lower intraocular pressure (IOP) to prevent disease progression. However, scarring of the filtering bleb limits their long-term success and Asian eyes are more at risk. Although this is so, many existing studies have been done on Caucasian patients, but few have focused solely on Asian patients. Intraoperative anti-metabolites such as Mitomycin-C (MMC) and 5-Fluorouracil (5-FU) are the current mainstay of adjunctive treatments to reduce scarring, and in this review, we evaluate the evolution, benefits and side effects of these agents. Recently, newer methods of wound modulation including anti-vascular endothelial growth factor (VEGF) agents and collagen implants are also being investigated as part of a multi-pronged approach to tackle this problem. Some opportunities exist to limit scarring post-operatively, but it is an ongoing battle.

Use of a 24 gauge intravenous cannula for minimally invasive trabeculectomy

We describe an innovative technique for performing standardized low cost glaucoma filtration surgery using a polytetrafluoroethylene (PTFE) intravenous cannula. The trocar of a 24 gauge (24G) PTFE intravenous cannula was used to create a trabeculectomy ostium and its tube was inserted under a partial thickness scleral flap in 2 patients with advanced glaucomatous optic neuropathy, in whom intraocular pressure (IOP) was not controlled on maximal tolerable hypotensive therapy. Postoperatively, IOP of the operated eyes at 3, 6 and 9 months’ follow-up ranged from 12 to 15 mmHg with a well formed anterior chamber and a diffuse bleb.

Incidence, efficacy and safety of YAG laser goniopuncture following nonpenetrating deep sclerectomy at a university hospital in Riyadh, Saudi Arabia

Purpose

Assessing the frequency and evaluating the efficacy and safety of Neodymium:Yttrium Aluminum Garnet (Nd:YAG) Laser goniopuncture (LGP) following nonpenetrating deep sclerectomy (NPDS).

Design

Retrospective cohort study.

Patients and methods

We retrospectively reviewed the outcome of 197 eyes of 153 patients with open angle glaucoma who underwent either NPDS or NPDS combined with cataract extraction between January 2005 and September 2010 at King Abdulaziz University Hospital (KAUH). Both demographic and clinical data were retrieved and analysed.

Results

Goniopuncture (GP) was needed in 48 (24.4%) of the eyes which had NPDS or NPDS with cataract extraction after a mean post operative interval of 9.78 (±11.16) months. The mean IOP had significantly decreased from 23.3 (±5.9) mmHg prior to Nd:YAG LGP procedure to 14.6 (±4.4) mmHg at the last post-procedure assessment. At the last follow-up; Nd:YAG LGP was successful in controlling IOP in 27 eyes (56.3%). Mean Nd:YAG LGP failure time was 6.04 (±5.80) months. Young age (<50 years) (p = 0.001); type of glaucoma (secondary versus primary open angle, p = 0.0258) and the use of drainage implant (p = 0.038) were the identified predicting factors for the need of Nd:YAG LGP. Complications following Nd:YAG LGP occurred in 5 eyes (iris touch to TDM (4.2%), Hyphema (2.1%), hypotony maculopathy (2.1%) and choroidal detachment (2.1%).

Conclusions

LGP is an efficient IOP lowering procedure after NPDS, when it is indicated. It is a simple and noninvasive procedure. However, certain precautions should be taken to avoid complications.

Comparison of outcomes of trabeculectomy with mitomycin C vs. ologen implant in primary glaucoma

Purpose:

To compare the safety and efficacy of trabeculectomy with Ologen implant vs. trabeculectomy with Mitomycin C (MMC).

Materials and Methods:

In a prospective, randomized, pilot study, 39 eyes of 33 subjects with medically uncontrolled primary glaucoma, aged 18 years or above underwent trabeculectomy either with MMC (20 eyes) or with Ologen implant (19 eyes). The primary outcome measure was cumulative success probability, defined as complete if the intraocular pressure (IOP) was > 5 and ≤ 21 mm Hg without anti-glaucoma medications or additional surgery and qualified if an IOP was > 5 and ≤ 21 mm Hg with or without anti-glaucoma medications.

Results:

Mean (± standard deviation) follow-up in Ologen group was 19.1 ± 8.1 months, and in MMC group was 18.0 ± 8.4 months. Mean IOP reduction at 6 months was significantly lower (P = 0.01) in the MMC group (11.9 ± 2.9 mm Hg) as compared to Ologen group (14.6 ± 2.7 mm Hg). However, at 12 months (P = 0.81) and 24 months (P = 0.32), the mean IOP was similar between the 2 groups. Complete success probability at the end of 6 months in Ologen group was 100% (95% confidence interval: 59.1 - 99.0) was similar (P = 0.53) to that in MMC group (93.8%, 95% CI: 63.2 - 99.1). The incidences of early post-operative complications were similar in the 2 groups, except hyphema, which was significantly more in Ologen group (P = 0.02).

Conclusion:

In this pilot study, the success of trabeculectomy and complications were similar in both Ologen and MMC groups at the end of 6 months.

The efficacy of viscocanalostomy for uncontrollable primary open-angle glaucoma in a developing country

PURPOSE

To evaluate the safety and efficacy of viscocanalostomy in the management of medically uncontrollable primary open-angle glaucoma (POAG) in a developing country.

MATERIALS AND METHODS

This is a prospective, non-randomized case series of 14 consecutive eyes with medically uncontrollable POAG, all subjected to viscocanalostomy. The main outcome measure was success rate based on the intraocular pressure (IOP) level achieved post-operatively. The procedure was considered a complete success if IOP was less than 21 mmHg without any anti-glaucoma medication. Qualified success was defined as IOP of less than 21 mmHg with anti-glaucoma medication. All patients had a regular follow-up of at least 12 months.

RESULTS

IOP was reduced from a mean baseline value of 27.9 ± 7.3 mmHg (range: 21-40 mmHg) to a mean final value of 16.0 ± 2.7 mmHg (range: 13-22 mmHg), which was statistically highly significant (P < 0.005). The mean number of pre-operative anti-glaucoma medications was 3.0 ± 0.4 (range: 2-4), which was reduced significantly (P < 0.0001) to 0.3 ± 0.6 (range: 0-2) at the last follow-up visit. One year post-operatively, complete success was achieved in 71% and qualified success was observed in 21.4% of patients, summing up to an overall success rate of 92.4%. There were no major complications in any of the patients.

CONCLUSION

Viscocanalostomy could be performed effectively and safely for control of POAG in developing countries.

Development of a micro-mechanical valve in a novel glaucoma implant

This paper describes methods for design, manufacturing and characterization of a micro-mechanical valve for a novel glaucoma implant. The implant is designed to drain aqueous humour from the anterior chamber of the eye into the suprachoroidal space in case of an elevated intraocular pressure (IOP). In contrast to any existing glaucoma drainage device (GDD), the valve mechanism is located in the anterior chamber and there, surrounded by aqueous humour, immune to fibrosis induced failure. For the prevention of hypotony the micro-mechanical valve is designed to open if the physiological pressure difference between the anterior chamber and the suprachoroidal space in the range of 0.8 mmHg to 3.7 mmHg is exceeded. In particular the work includes: (i) manufacturing and morphological characterization of polymer tubing, (ii) mechanical material testing as basis for (iii) the design of micro-mechanical valves using finite element analysis (FEA), (iv) manufacturing of microstent prototypes including micro-mechanical valves by femtosecond laser micromachining and (v) the experimental fluid-mechanical characterization of the manufactured microstent prototypes with regard to valve opening pressure. The considered materials polyurethane (PUR) and silicone (SIL) exhibit low elastic modulus and high extensibility. The unique valve design enables a low opening pressure of micro-mechanical valves. An ideal valve design for PUR and SIL with an experimentally determined opening pressure of 2 mmHg and 3.7 mmHg is identified. The presented valve approach is suitable for the inhibition of hypotony as a major limitation of today's GDD and will potentially improve the minimally invasive treatment of glaucoma.