Outcomes of glaucoma reoperations in the Tube Versus Trabeculectomy (TVT) Study

Efficacy and Safety of an Adjustable Glaucoma Drainage Device (eyeWatch System) for Refractory Glaucoma: A 2-Year Prospective Study

PRCIS

In this study, we report a 2-year follow-up after implantation of an adjustable glaucoma drainage device combined with a novel orbital filtering plate. The IOP was efficiently controlled postoperatively with limited complications and an excellent safety profile.

PURPOSE

To report the clinical results at 2 years after implantation of an eyeWatch (eW) system, which comprises an adjustable glaucoma drainage device (eW implant) combined with a novel orbital filtering plate (eyePlate), in refractory glaucoma.

PATIENTS AND METHODS

Monocentric, prospective, noncomparative clinical trial. Patients suffering from refractory glaucoma after several failed surgeries were operated using the eW system. The primary outcome was the success rate, defined as an IOP ≤18 mm Hg and reduction of more than 20% from baseline, IOP ≥6 mm Hg. Secondary outcomes were mean IOP, visual acuity, the number of antiglaucoma medications, and the number and type of complications.

RESULTS

Forty-two eyes from 42 patients were included. The mean follow-up time was 22.0±4.0 months. The mean baseline IOP decreased from 23.2±7.2 mm Hg before surgery to 11.9±4.4 mm Hg at 12 months ( P <0.001) and 11.5±3.0 at 24 months. The mean number of glaucoma medications decreased from 2.9±0.9 before surgery to 0.7±0.9 at 12 months ( P <0.001) and 1.0±0.9 at 24 months. The qualified success rate was 93% at 12 months and 90% at 24 months whereas the complete success rate was 46% and 40% at 12 and 24 months, respectively. Complications occurred in 7 patients.

CONCLUSIONS

Implantation of the eW system effectively lowered IOP and reduced glaucoma medications for a 2-year period in patients who had previously failed glaucoma surgery. Persistent hypotony was not observed and the number of complications was low.

Changes to glaucoma surgery patterns during the coronavirus disease 2019 pandemic: a shift towards less invasive procedures

PURPOSE

The aim of the study was to compare the quantity, type of glaucoma surgeries, and the disease stage before and during the coronavirus disease 2019 (COVID-19) pandemic.

METHODS

This was a retrospective, single-centre consecutive case series that included medical records of patients who underwent glaucoma surgery at the University Hospital in Białystok between 4 September, 2018, and 3 March, 2020 (pre-pandemic group) and compared it with patients treated between 4 March, 2020, and 4 September, 2021 (pandemic group). Adult patients with primary or secondary open-angle or closed-angle glaucoma who underwent surgery were included in this study. Finally, 534 operated eyes (362 and 172 eyes operated on before and during the pandemic, respectively) were examined.

RESULTS

The number of glaucoma surgeries dropped by 50% during the pandemic compared to a similar pre-pandemic period, with a significant difference in the kind of procedure between the two groups (p < 0.001). The most common procedures in the pre-pandemic group were Ex-Press implantation (33.7%) and trabeculectomy (31.5%). Within the pandemic group, half of the eyes underwent trabeculectomy (50.0%), followed by Preserflo microshunt (11.6%), iStent (8.7%), and transscleral cyclophotocoagulation (TSCP) (8.7%). A significant difference in the average intraocular pressure was revealed among patients who qualified for surgery.

CONCLUSION

The COVID-19 pandemic is associated with a decrease in the number of extended antiglaucoma procedures and an increase in the number of short procedures performed, such as TSCP and minimally invasive glaucoma surgery.Key MessagesOur study has shown the negative impact of the COVID-19 pandemic in reducing the number of antiglaucoma procedures.The number of glaucoma surgeries dropped by 50% during the pandemic compared to those in a similar pre-pandemic period, and the type of performed procedures has changed.The COVID-19 pandemic is associated with a decrease in the number of combined antiglaucoma procedures, in opposite: the number of minimally invasive glaucoma surgeries increased due to safety reasons.

Microfluidics in the eye: a review of glaucoma implants from an engineering perspective

Glaucoma is a progressive optic neuropathy in the eye, which is a leading cause of irreversible blindness worldwide and currently affects over 70 million individuals. Clinically, intraocular pressure (IOP) reduction is the only proven treatment to halt the progression of glaucoma. Microfluidic devices such as glaucoma drainage devices (GDDs) and minimally invasive glaucoma surgery (MIGS) devices are routinely used by ophthalmologists to manage elevated IOP, by creating an artificial pathway for the over-accumulated aqueous humor (AH) in a glaucomatous eye, when the natural pathways are severely blocked. Herein, a detailed modelling and analysis of both the natural microfluidic pathways of the AH in the eye and artificial microfluidic pathways formed additionally by the various glaucoma implants are conducted to provide an insight into the causes of the IOP abnormality and the improvement schemes of current implant designs. The mechanisms of representative glaucoma implants have been critically reviewed from the perspective of microfluidics, and we have categorized the current implants into four groups according to the targeted drainage sites of the AH, namely Schlemm's canal, suprachoroidal space, subconjunctival space, and ocular surface. In addition, we propose to divide the development and evolution of glaucoma implant designs into three technological waves, which include microtube (1st), microvalve (2nd) and microsystem (3rd). With the emerging trends of minimal invasiveness and artificial intelligence in the development of medical implants, we envision that a comprehensive glaucoma treatment microsystem is on the horizon, which is featured with active and wireless control of IOP, real-time continuous monitoring of IOP and aqueous rate, etc. The current review could potentially cast light on the unmatched needs, challenges, and future directions of the microfluidic structural and functional designs of glaucoma implants, which would enable an enhanced safety profile, reduced complications, increased efficacy of lowering IOP and reduced IOP fluctuations, closed-loop and on-demand control of IOP, etc.

Eyewatch adjustable drainage device in vitrectomized eyes with refractory glaucoma

BACKGROUND

To describe the efficacy and safety of the adjustable system eyeWatch in vitrectomized glacomatous eyes.

METHODS

Prospective, non-comparative, small case series of 2 patients who underwent glaucoma drainage device implant with the eyeWatch system. Intraocular pressure, number of medications and early and late complications were evaluated.

RESULTS

None of the operated eyes developed early or late complications. After 1 week post operatively, the IOP raised at 28 mmHg in the first eye and 25 mmHg in the second one. The eyeWatch Pen was used to open and set the device into position 3 (that means implant half opened) After waiting for 30 min, IOP was 15 mmHg and 11 mmHg, respectively. Thirty days after surgery we set the EyeWatch into position 0 (that means implant full opened) even though the IOP was under control. A new IOP measurement was done and we registered that IOP was 14 mmHg and 10 mmHg respectively, and it remained stable after six months of follow up.

CONCLUSION

In conclusion, in our case series the use of eyeWatch adjustable system allows a safe and gradual regulation of the flow during post-operative management also in vitrectomized eyes. Considering the percentage of hypotony related complications in vitrectomized eyes this system is an effective and safe technique to handle glaucoma in post vitreoretinal surgery eyes.

Outcomes of Glaucoma Reoperations in the Primary Tube Versus Trabeculectomy Study

PURPOSE

To describe the incidence and outcomes of reoperations for glaucoma in the Primary Tube Versus Trabeculectomy (PTVT) Study.

DESIGN

Cohort study of patients in a multicenter randomized clinical trial.

PARTICIPANTS

The PTVT Study enrolled 242 patients with medically uncontrolled glaucoma and no previous incisional ocular surgery.

METHODS

Randomization assigned 125 patients to placement of a tube shunt (350-mm2 Baerveldt glaucoma implant) and 117 patients to trabeculectomy with mitomycin C (MMC, 0.4 mg/ml for 2 minutes). Data were analyzed from patients who underwent additional glaucoma surgery.

MAIN OUTCOME MEASURES

Outcome measures included intraocular pressure (IOP), use of glaucoma medications, visual acuity, surgical complications, and failure (IOP > 21 mmHg or reduced by <20%, IOP ≤ 5 mmHg, additional glaucoma surgery, or loss of light perception vision).

RESULTS

Additional glaucoma surgery was performed in 21 patients in the tube group and 12 patients in the trabeculectomy group in the PTVT Study, and the 5-year cumulative reoperation rate for glaucoma was 18.0% in the tube group and 10.4% in the trabeculectomy group (P = 0.15). Follow-up (mean ± standard deviation [SD]) after additional glaucoma surgery was 35.1 ± 17.7 months in the tube group and 30.1 ± 17.6 months in the trabeculectomy group (P = 0.44). At 3 years after glaucoma reoperation, IOP (mean ± SD) was 15.5 ± 4.8 mmHg in the tube group and 16.6 ± 7.3 mmHg in the trabeculectomy group (P = 0.71). The number of glaucoma medications (mean ± SD) after 3 years of follow-up was 2.1 ± 1.7 in the tube group and 1.7 ± 1.0 in the trabeculectomy group (P = 0.58). The cumulative probability of failure at 3 years after a glaucoma reoperation was 37.8% in the tube group and 21.3% in the trabeculectomy group (P = 0.47).

CONCLUSION

No significant difference in the rate of reoperation for glaucoma was observed after tube shunt implantation and trabeculectomy with MMC in the PTVT Study. Similar surgical outcomes were observed after additional glaucoma surgery, irrespective of the initial procedure to which the patient was randomized.

FINANCIAL DISCLOSURE(S)

Proprietary or commercial disclosure may be found after the references.

Comparison of tube shunt implantation and trabeculectomy for glaucoma: a systematic review and meta-analysis

OBJECTIVE

To compare the efficacy and safety of tube shunt implantation with trabeculectomy in the treatment of patients with glaucoma.

METHODS

A systematic literature search was performed for studies comparing tube with trabeculectomy in patients with glaucoma (final search date: 27 February 2022). Comparisons between tube and trabeculectomy were grouped by the type of tube (Ahmed, Baerveldt, Ex-PRESS and XEN). The primary endpoints included intraocular pressure (IOP), IOP reduction (IOPR), IOPR percentage (IOPR%), complete success rate (CSR), qualified success rate (QSR) and adverse events (AEs).

RESULTS

Forty-nine studies were included in this meta-analysis and presented data for 3795 eyes (Ahmed: 670, Baerveldt: 561, Ex-PRESS: 473, XEN: 199, trabeculectomy: 1892). Ahmed and Ex-PRESS were similar to trabeculectomy in terms of IOP outcomes and success rate (Ahmed vs trabeculectomy: IOPR%: mean difference (MD)=1.34 (-5.35, 8.02), p=0.69; Ex-PRESS vs trabeculectomy: IOPR%: MD=0.12 (-3.07, 3.31), p=0.94). The IOP outcomes for Baerveldt were worse than those for trabeculectomy (IOPR%: MD=-7.51 (-10.68, -4.35), p<0.00001), but the QSR was higher. No significant difference was shown for the CSR. XEN was worse than trabeculectomy in terms of IOP outcomes (IOPR%: MD=-7.87 (-13.55, -2.18), p=0.007), while the success rate was similar. Ahmed and Ex-PRESS had a lower incidence of AEs than trabeculectomy. Baerveldt had a lower incidence of bleb leakage/wound leakage, hyphaema and hypotonic maculopathy than trabeculectomy but a higher incidence of concurrent cataracts, diplopia/strabismus and tube erosion. The incidence of AEs was similar for the XEN and trabeculectomy procedures.

CONCLUSION

Compared with trabeculectomy, both Ahmed and Ex-PRESS appear to be associated with similar ocular hypotensive effects and lower incidences of AEs. However, Baerveldt and XEN cannot achieve sufficient reductions in IOP outcomes similar to those of trabeculectomy.

PROSPERO REGISTRATION NUMBER

CRD42021257852.

FP and EP2 prostanoid receptor agonist drugs and aqueous humor outflow devices for treating ocular hypertension and glaucoma

Prostaglandin (PG) receptors represent important druggable targets due to the many diverse actions of PGs in the body. From an ocular perspective, the discovery, development, and health agency approvals of prostaglandin F (FP) receptor agonists (FPAs) have revolutionized the medical treatment of ocular hypertension (OHT) and glaucoma. FPAs, such as latanoprost, travoprost, bimatoprost, and tafluprost, powerfully lower and control intraocular pressure (IOP), and became first-line therapeutics to treat this leading cause of blindness in the late 1990s to early 2000s. More recently, a latanoprost-nitric oxide (NO) donor conjugate, latanoprostene bunod, and a novel FP/EP3 receptor dual agonist, sepetaprost (ONO-9054 or DE-126), have also demonstrated robust IOP-reducing activity. Moreover, a selective non-PG prostanoid EP2 receptor agonist, omidenepag isopropyl (OMDI), was discovered, characterized, and has been approved in the United States, Japan and several other Asian countries for treating OHT/glaucoma. FPAs primarily enhance uveoscleral (UVSC) outflow of aqueous humor (AQH) to reduce IOP, but cause darkening of the iris and periorbital skin, uneven thickening and elongation of eyelashes, and deepening of the upper eyelid sulcus during chronic treatment. In contrast, OMDI lowers and controls IOP by activation of both the UVSC and trabecular meshwork outflow pathways, and it has a lower propensity to induce the aforementioned FPA-induced ocular side effects. Another means to address OHT is to physically promote the drainage of the AQH from the anterior chamber of the eye of patients with OHT/glaucoma. This has successfully been achieved by the recent approval and introduction of miniature devices into the anterior chamber by minimally invasive glaucoma surgeries. This review covers the three major aspects mentioned above to highlight the etiology of OHT/glaucoma, and the pharmacotherapeutics and devices that can be used to combat this blinding ocular disease.

Internal Tube Occlusion with An Easily Removable Non-Absorbable Double Suture: A Novel Surgical Technique Adjunct for Non-Valved Glaucoma Drainage Devices

To describe a surgical variant for non-valved glaucoma drainage device implants using an easily removable non-absorbable double suture into the lumen of the tube. A retrospective, non-comparative case series of 10 patients who underwent a non-valved glaucoma drainage device implant with an endoluminal double-suture for refractory glaucoma. The sutures were easily removed postoperatively without the need for an operating room. Intraocular pressure, number of medications, and early and late complications were evaluated with a follow-up of 12 months. None of the eyes that underwent an operation developed early or late complications. The first endoluminal suture was removed in all eyes with a mean time of removal of 30 ± 7 days. The second suture was removed in all eyes with a mean time of removal of 90 ± 7 days. No complications were noted, either, after or during suture removal. The mean preoperative IOP was 27.3 ± 4.0 and the postoperative IOP, at the end of the follow-up, was 12.7 ± 1.4. At the end of the follow-up, six patients (60%) achieved complete success and four patients (40%) achieved qualified success. In conclusion, in our case series, the surgical variant allowed for a safe and gradual regulation of the flow during postoperative management. Considering the efficacy of non-valved glaucoma drainage devices, an improvement in the safety profile allows surgeons to broaden the surgical indications.

Treatment Outcomes in the Primary Tube Versus Trabeculectomy Study after 5 Years of Follow-up

PURPOSE

To report 5-year treatment outcomes in the Primary Tube Versus Trabeculectomy (PTVT) Study.

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

The primary outcome measure was the rate of surgical failure, defined as intraocular pressure (IOP) > 21 mmHg or reduced < 20% from baseline, IOP ≤ 5 mmHg, reoperation for glaucoma, or loss of light perception. Secondary outcome measures included IOP, glaucoma medical therapy, and visual acuity.

RESULTS

The cumulative probability of failure after 5 years of follow-up was 42% in the tube group and 35% in the trabeculectomy group (P = 0.21; hazard ratio = 1.31; 95% confidence interval = 0.86-2.01). At 5 years, IOP (mean ± standard deviation) was 13.4 ± 3.5 mmHg in the tube group and 13.0 ± 5.2 mmHg in the trabeculectomy group (P = 0.52), and the number of glaucoma medications (mean ± standard deviation) was 2.2 ± 1.3 in the tube group and 1.3 ± 1.4 in the trabeculectomy group (P < 0.001).

CONCLUSIONS

Trabeculectomy with MMC and tube shunt surgery produced similar IOPs after 5 years of follow-up in the PTVT Study, but fewer glaucoma medications were required after trabeculectomy. No significant difference in the rate of surgical failure was observed between the 2 surgical procedures at 5 years.

Efficacy of the PRESERFLO MicroShunt and a Meta-Analysis of the Literature

Background: Recent studies on the PRESERFLO MicroShunt suggest that it may be effective in lowering intraocular pressure (IOP); however, the number of studies on this device remains limited. Therefore, we assessed the efficacy of the PRESERFLO MicroShunt in patients with glaucoma and performed a meta-analysis of published results. Methods: Prospective study including all patients that underwent PRESERFLO MicroShunt surgery from 2018 onwards. Sub-analyses were performed for cataract-combined procedures. To compare our results, we performed a systematic review and meta-analysis. IOP, IOP-lowering medication and surgical complications reported in the retrieved studies were assessed. Results: A total of 72 eyes underwent PRESERFLO-implant surgery (59 as standalone procedure and 13 as cataract-combined procedure). No significant differences were found in IOP and IOP-lowering medication between both groups. The mean ± standard deviation IOP and IOP-lowering medications of both groups taken together declined from 21.72 ± 8.35 to 15.92 ± 8.54 mmHg (p < 0.001, 26.7% reduction) and 3.40 to 0.93 (p < 0.001, 72.6% reduction) at 1 year follow-up, respectively. Secondary surgeries were required in 19.4% of eyes, the majority (71.4%) within 6 months. The meta-analysis including 14 studies (totaling 1213 PRESERFLO MicroShunt surgeries) from the systematic review showed a mean preoperative IOP and IOP-lowering medication of 22.28 ± 5.38 and 2.97 ± 1.07, respectively. The three-years postoperative pooled mean was (weighted mean difference, 95% CI) 11.07 (10.27 [8.23−12.32], p < 0.001) mmHg and 0.91 (1.77 [1.26−2.28], p < 0.001) for IOP and IOP-lowering medication, respectively. The most common reported complication was hypotony (2−39%). Conclusion: The PRESERFLO MicroShunt is effective and safe in lowering IOP and the number of IOP-lowering medications.

Reoperations for complications within 90 days after gel stent implantation or trabeculectomy

Purpose

To describe reoperations in the operating room for complications that occurred within the first 90 days after gel stent implantation or trabeculectomy at a single institution over 5 years.

Methods

In this retrospective chart review, patients who have undergone gel stent implantation with mitomycin C (MMC) or trabeculectomy with MMC were enrolled. Postoperative complications that required reoperations within the first 90 days were evaluated.

Results

A total of 510 surgeries were performed on 392 patients over a 57-month period by 2 glaucoma surgeons. Of these, 284 were gel stent implantation, and 226 were trabeculectomy. Combined phacoemulsification was performed in 52/284 (18.3%) in the gel stent group and in 26/226 (11.5%) of eyes in the trabeculectomy group (p = 0.03). Reoperations took place in 13/510 (2.5%) eyes, including 4/284 (1.4%) in the gel stent group, 9/226 (4.0%) in the trabeculectomy group (p = 0.07). In the gel stent group, indications for reoperation were bleb failure (2), suprachoroidal hemorrhage (1), bullous keratopathy (1). In the trabeculectomy group, indications for reoperation were bleb failure (3), overfiltration (2), persistent wound leak (2), aqueous misdirection (2).

Conclusions

The rates of reoperation for early postoperative complications after gel stent or trabeculectomy was low and comparable with previous studies. A slightly higher number of reoperations within 90 days was observed in the trabeculectomy group than the gel stent group despite the more significant number of combined procedures in the latter group. Bleb failure was the most common indications for reoperation in both groups. Excessive outflow was a cause of reoperation mostly in the trabeculectomy group.

Corneal Endothelial Cell Loss in Patients After Minimally Invasive Glaucoma Surgery: Current Perspectives

Minimally invasive glaucoma surgery (MIGS) is a rapidly expanding category of surgical glaucoma treatment options that offer a superior safety profile compared with traditional approaches for reducing intraocular pressure. However, MIGS may cause corneal endothelial cell loss; therefore, it has been receiving increasing attention. This systematic review aimed to evaluate and compare the rate and degree of corneal endothelial loss after MIGS. First, this paper presents an overview of the theoretical effectiveness of MIGS, the fundamental aspects regarding the roles of endothelial cells, and the effect of cataract surgery on the quality and count of endothelial cells. Further, we detail the various surgical techniques involved in MIGS, the development of these techniques over the time, and clinical aspects to consider with respect to the endothelial cell count. We discuss in detail the COMPASS-XT study, which was based on data collected over 5 years, reported that withdrawal of the CyPass Micro-Stent (Alcon Laboratories) yielded increased corneal endothelial cell loss. Generally, MIGS procedures are considered safe, with the incidence of complications ranging from 1% to 20% depending on the surgery type; however, there is still need for studies with longer follow-up. Thus, an adequate count of endothelial cells in the central cornea portion is recommended as necessary for candidate patients for MIGS.

Modified Trabeculectomy versus Glaucoma Drainage Implant Surgery: A Retrospective Comparative Study for Refractory Glaucoma Treatment

Purpose

To observe and compare the efficacy of modified trabeculectomy (TE), Ahmed drainage valve implantation (AGV), and EX-PRESS glaucoma shunt for refractory glaucoma (RG).

Methods

The study population of this retrospective study comprised 73 patients (76 eyes) who were suffering from RG and treated with modified TE, AGV, and EX-PRESS glaucoma shunt in our hospital from October 2012 to October 2020. The number of cases who underwent modified TE, AVG, and EX-PRESS glaucoma shunt was 36 (38 eyes). 19 (20 eyes), and 18 patients (18 eyes), respectively. The intraocular pressure (IOP), best-corrected visual acuity (BCVA), postoperative antiglaucoma medications, filter bubble morphology, anterior chamber depth (ACD), successful rate, and postoperative complications were recorded and statistically analyzed preoperative and 1 d, 1 w, 1 mon, 3 mon, 6 mon, and the end follow-up after operation.

Results

The BCVA differed insignificantly among the three cohorts before and 6 months after surgery. Compared to preoperative BCVA, the postoperative BCVA of the three groups had no statistical significance. An obvious reduction in IOP was observed in all the three group after operation (P < 0.05). An obvious decrease in antiglaucoma medications was observed after surgery in all the three groups (P < 0.05). The AGV group showed deeper ACD postoperatively, while no marked difference was found in postoperative ACD in the other two groups. The total success rates in modified TE and AGV groups were slightly higher than those in the EX-PRESS group. The three groups differed insignificantly in filter bubble morphology after operation.

Conclusion

Modified TE, AGV, and EX-PRESS glaucoma shunt showed equivalent efficacy for RG, which could validly reduce IOP and postoperative antiglaucoma medications. However, the success rates of modified TE and AGV were slightly higher than those of EX-PRESS glaucoma shunt in the last follow-up, and their complications were slightly less than those of the EX-PRESS glaucoma shunt.

Reintervention rate in glaucoma filtering surgery: A systematic review and meta-analysis

PURPOSE

Reintervention rate is an important factor impacting on patients, surgeons, and society. To date, only a few studies have focused on this topic. For this reason, a systematic review and meta-analysis was undertaken to assess the reintervention rate after glaucoma filtering surgery.

MATERIALS AND METHODS

Prospective studies reporting the reintervention rate after glaucoma filtering surgery and with at least 12 months of follow-up were systematically searched on PubMed, Medline and Embase databases. The primary outcome was the total reintervention rate following surgery. Secondary outcomes were: the rate of manipulation, in-clinic and in-operating room reintervention; the reintervention rate for intraocular pressure (IOP) control and for complications; demographic, clinical and surgical variables associated with reintervention rate.

RESULTS

Ninety-three studies with a total of 8345 eyes were eligible. The total reintervention rate was 1.84 (95% CI 1.57-2.13), with a lower rate for Baerveldt (0.53, 95% CI 0.29-0.83) and Preserflo (0.60, 95% CI 0.15-1.29), and a higher rate for Xen (4.26, 95% CI 2.59-6.31). The manipulation rate was 0.99 (95% CI 0.77-1.23), the in-clinic reintervention rate was 0.08 (95% CI 0.05-0.12) and the in-operating room reintervention rate was 0.28 (95% CI 0.22-0.35). The reintervention rate for IOP control was 1.26 (95% CI 1.04-1.51) and the reintervention rate for complications was 0.27 (95% CI 0.21-0.35).

CONCLUSIONS

All types of surgery presented a total reintervention rate similar to the overall findings, except studies on Baerveldt and Preserflo Microshunt, with a lower rate, and Xen, with a higher rate. None of the variables evaluated were found to be directly associated with the explored outcomes.

Microinvasive glaucoma surgery: a review and classification of implant-dependent procedures and techniques

The aim of this article is to discuss how physiology and anatomical background affect the effectiveness of implant‐dependent microinvasive glaucoma surgery (MIGS). First, we provide a micro view of aqueous outflow and tissue behaviour. Second, we review studies exploring the mechanisms of the pressure‐lowering effect of MIGS, as well as tissue behaviour during aqueous flow and tissue motion. We also describe and classify microinvasive surgical procedures and the most important types of implants, as well as their mechanisms of action, implantation techniques and efficacy. Further, we summarize the indications and surgical results presented in recent studies, providing an evidence‐based update on novel and emerging MIGS techniques for the treatment of open‐angle glaucoma. These data can help surgeons to personalize the management of glaucoma and to choose the best MIGS option for individual glaucoma patients.

Outcomes of XEN Gel Stent Implantation in the Inferonasal Quadrant after Failed Trabeculectomy

Aim and objective

To evaluate the efficacy and safety of XEN stent implantation in the inferonasal quadrant after prior failed trabeculectomy.

Materials and methods

Fourteen open-angle glaucoma patients with prior failed trabeculectomy were recruited to this retrospective study. Implantation of the stent was performed as a stand-alone procedure. The mean follow-up duration was 14.2 months. Best-corrected visual acuity, intraocular pressure (IOP), number of medications, complications, and the requirement for additional procedures were among the outcome measures recorded.

Results

Mean IOP reduced by 49.3% from 24.14 ± 2.74 mm Hg preoperatively to 12.23 ± 2.89 mm Hg at month 12 (p < 0.001). Medication usage reduced from 3.71 ± 0.47 medications preoperatively to 1.31 ± 1.55 at month 12 (p = 0.003). Adverse events included transient slight intracameral hemorrhage (5 eyes, 35.7%), second trabeculectomy required (2 eyes, 14.3%), and numerical hypotony (IOP <5 mm Hg, in 3 cases, 21.4%), all of which resolved spontaneously. Six eyes (42.8%) required postoperative bleb needling to further reduce IOP. There were no cases of vision loss, stent exposure, hypotony, lower eyelid malposition, bleb dysesthesia, or bleb-related infection.

Conclusion

XEN gel stent implantation in the inferonasal quadrant can be considered a viable surgical option for patients with a history of previously failed trabeculectomy requiring further IOP lowering.

Clinical significance

To the best of our knowledge, this is the first case series describing the outcome of inferonasal implantation of XEN gel stent following failed trabeculectomy.

How to cite this article

Düzgün E, Olgun A, Karapapak M, et al. Outcomes of XEN Gel Stent Implantation in the Inferonasal Quadrant after Failed Trabeculectomy. J Curr Glaucoma Pract 2021;15(2):64–69.

Reoperation Rates and Disease Costs for Primary Open-Angle Glaucoma Patients in the United States Treated with Incisional Glaucoma Surgery

PURPOSE

To evaluate the claims-based 5-year economic and reintervention burden for patients with primary open-angle glaucoma (POAG) after incisional glaucoma surgery in the United States.

DESIGN

Retrospective Medicare claims analysis.

PARTICIPANTS

One thousand nine hundred forty-five Medicare fee-for-service patients with POAG treated with trabeculectomy, tube shunt, or EX-PRESS shunt procedures from 2010 through 2011.

METHODS

Patients with POAG treated with incisional glaucoma surgery (trabeculectomy, tube shunt, or EX-PRESS shunt) from 2010 through 2011 were identified in the Medicare 5% Standard Analytical Files. Ten years of claims data for each patient (2005-2016) were evaluated for prior incisional surgeries and downstream procedures in the treated eye within 5 years of index. Patients' characteristics, downstream procedures, and POAG-related costs were evaluated. Proportions of patients with downstream procedures in the index eye indicating failure of the index surgery, glaucoma reoperations, nonfailure complications, interventions, or cataract surgery were assessed over 5 years of follow-up.

MAIN OUTCOME MEASURES

Cumulative rates of index surgery failure and glaucoma reoperations over 5 years after incisional glaucoma surgery.

RESULTS

Of 1945 patients, 223 underwent EX-PRESS shunt, 551 underwent tube shunt, and 1171 underwent trabeculectomy at index. Rates of failure, glaucoma reoperations, or nonfailure complications rose over 5 years after index for all patient subgroups. At 1 year, 15.1% of EX-PRESS shunt patients, 11.6% of tube shunt patients, and 8.8% of trabeculectomy patients had experienced failure based on postindex procedures. By 5 years follow-up, these rates were 31.5% of EX-PRESS shunt patients, 27.1% of tube shunt patients, and 23.5% of trabeculectomy patients. Five-year rates of glaucoma reoperations were 18.3%, 14.0%, and 15.1%, respectively. Among tube shunt and trabeculectomy patients with prior incisional surgery, the 5-year failure rates were 32.5% and 32.6%, and reoperations rates were 12.0% and 26.1%, respectively.

CONCLUSIONS

More than one-fourth of patients with POAG treated with incisional surgery underwent additional procedures to address index surgery failure within 5 years. Of these, more than half underwent additional incisional glaucoma surgery. These outcomes from clinical practice settings demonstrate that patients with POAG who require incisional surgery continue to need additional safe and effective surgical treatment options to manage their glaucoma.

Long-term prognosis for glaucoma in patients with Posner-Schlossman syndrome

BACKGROUND

The aim of this study is to investigate the long-term prognosis for glaucoma in patients with Posner-Schlossman syndrome (PSS).

METHODS

In this retrospective case series study, a total of 98 patients with PSS from January 2014 to February 2019 were included in this study. Initial presentations and follow-up data were obtained from medical records. Vision-related quality of life (VR-QoL) was assessed using the 25-item National Eye Institute Visual Functioning Questionnaire.

RESULTS

Of the 98 patients included in the study, 66 (67%) presented with glaucoma, and among them, 21 (32%) required glaucoma surgery. The mean follow-up time was 50.1 months (range 1-263 months). Iris involvement was noted in 46 (46.9%) eyes; 26 (26.5%) had sectoral iris changes and 20 (20.4%) showed diffuse iris changes. Eyes with iris involvement had a significantly higher number of acute attacks of uveitis than those without (p = 0.010). The 5-year glaucoma surgery-free interval was 77.8% according to Kaplan-Meier analysis. Significant predictors of glaucoma surgery included iris involvement (hazard ratio [HR] = 5.215; confidence interval [CI] = 1.387-19.610), highest number of anti-glaucoma agents (HR = 5.069; CI = 1.848-13.905), baseline average retinal nerve fiber layer thickness (RNFLT) thickness (HR = 0.949; CI = 0.917-0.982), and disease duration (HR = 0.977; CI = 0.957-0.996). Overall complete surgical success and qualified success at 2 years was 35.3% and 75.5%, respectively. Patients with iris involvement, glaucoma surgery, and thinner average RNFLT had significantly poorer VR-QoL (all, p < 0.05).

CONCLUSIONS

Patients with PSS and glaucoma required glaucoma surgery in a high rate. Iris involvement increased the probability of surgical treatment and lowered the VR-QoL of PSS patients.

Surgical outcomes after primary Baerveldt glaucoma implant surgery with vitrectomy for neovascular glaucoma

This study aimed to evaluate the 3-year long-term outcomes of primary Baerveldt glaucoma implant (BGI) surgery for neovascular glaucoma (NVG). We retrospectively evaluated 27 consecutive patients with NVG between November 2013 and November 2017. All the patients were treated with panretinal photocoagulation and pars plana vitrectomy before BGI surgery without anti-vascular endothelial growth factor treatment. The surgical success of the BGI was defined as an IOP of <22 mmHg and <5 mmHg with or without antiglaucoma medication. The outcomes were assessed on the basis of intraocular pressure (IOP), visual acuity, postoperative complications, and cumulative success rate. Except for 2 mortality cases, 25 eyes (92.6%) were followed up for 3 years. The mean IOPs (mmHg)/numbers of glaucoma medications ± standard error of the mean before and 12 and 36 months after BGI surgery were 41.6/4.6 ± 1.9/0.2, 14.8/2.2 ± 0.8/0.4 and 16.9/2.6 ± 1.1/0.3, respectively. In all of the follow-up time points, the postoperative mean IOP and number of glaucoma medications were statistically significantly lower than the preoperative values (analysis of variance, P < 0.001). At 3 years after surgery, the rates of visual acuity improvement (logMAR ≤ −0.3), invariance (−0.3 < logMAR < 0.3), and worsening (logMAR ≥ 0.3) were 56.0% (14/25 eyes), 24.0% (6/25 eyes), and 20.0% (5/25 eyes), respectively. The most common postoperative complications were hyphema (4 eyes, 14.8%) and vitreous hemorrhage (5 eyes, 18.5%), and serious complications such as expulsive hemorrhage, endophthalmitis, and tube/plate exposure did not occur. The cumulative probabilities of surgical success after the operation were 100% at 1 year, 85.2% at 2 years, and 77.4% at 3 years. In conclusion, combined non-valved pars plana tube placement in conjunction with vitrectomy was successful at lowering IOP with relatively low complication rates.

Microinvasive Glaucoma Surgery: A Review of Schlemm's Canal-Based Procedures

Microinvasive glaucoma surgery has gained popularity over the past decade. It can be performed using three different mechanisms. In the present review, we focused on Schlemm’s canal (SC)-based surgery, which increases aqueous humor (AH) outflow into the aqueous veins by either removal of the trabecular meshwork (TM) or an increase in the tension in the TM. In primary open-angle glaucoma (POAG), the TM is the most likely region for increased AH outflow resistance. Theoretically, removal of the TM can improve the AH outflow; hence, glaucoma specialists focus on microsurgical dissection of the TM. In this review, we analyzed the available literature to examine SC-related microsurgical modalities based on the histopathological proofs of the localization of resistance of the AH outflow. First, we considered the role, anatomy, and physiology of the TM and SC. We referred to studies that describe the mechanisms and potential pathways, related to increased intraocular pressure in the POAG, that are targeted using the SC-related microsurgical interventions. Next, we took a closer look at the gonioscopic tools necessary for an ab-interno approach and explored incision canal surgery: ab-interno trabeculectomy using different instrumentation (Trabectome^®, Kahook Dual Blade) and variations of the technique. Thereafter, we discussed ab-interno canaloplasty, explaining the technique and reviewing its effectiveness. Finally, we presented the scope for future research in the field. Although the iStent also targets SC by bypassing it, this device has been reviewed extensively elsewhere.

The Relationship of Travel Distance to Postoperative Follow-up Care on Glaucoma Surgery Outcomes

PRéCIS:: This study addresses the paucity of literature examining glaucoma patients' distance from clinic on postoperative follow-up outcomes. Greater distance from clinic was associated with higher likelihood of loss to follow-up and missed appointments.

PURPOSE

To investigate the relationship of patient travel distance and interstate access to glaucoma surgery postoperative follow-up visit attendance.

METHODS AND PARTICIPANTS

Retrospective longitudinal chart review of all noninstitutionalized adult glaucoma patients with initial trabeculectomies or drainage device implantations between April 4, 2014 and December 31, 2018. Patients were stratified into groups on the basis of straight-line distance from residence to University of North Carolina at Chapel Hill's Kittner Eye Center and distance from residence to interstate access. Corrective procedures, visual acuity, appointment cancellations, no-shows, and insurance data were recorded. Means were compared using 2-tailed Student t-test, Pearson χ, analysis of variance, and multivariate logistical regression determined odds ratios for loss to follow-up.

RESULTS

In total, 199 patients met all inclusion criteria. Six-month postoperatively, patients >50 miles from clinic had greater odds of loss to follow-up compared with patients <25 miles (odds ratios, 3.47; 95% confidence interval, 1.24-4.12; P<0.05). Patients >50 miles from clinic had significantly more missed appointments than patients 25 to 50 miles away, and patients <25 miles away (P=0.008). Patients >20 miles from interstate access had greater loss to follow-up than those <10 miles (t(150)=2.05; P<0.05). Mean distance from clinic was 12.59 miles farther for patients lost to follow-up (t(197)=3.29; P<0.01). Patients with Medicaid coverage had more missed appointments than those with Medicare plans (t(144)=-2.193; P<0.05).

CONCLUSIONS

Increased distance from clinic and interstate access are associated with increased missed appointments and loss to follow-up. Glaucoma specialists should consider these factors when choosing surgical interventions requiring frequent postoperative evaluations.

Minimally Invasive Surgery in Mild-to-Moderate Glaucoma Patients in Italy: Is It Time to Change?

Medical therapy is the first treatment choice for most patients with glaucoma; however, in a relevant proportion of patients, intraocular pressure (IOP) reduction is achieved with multi-therapy and/or high therapeutic doses. Conventional surgery is the standard alternative to medical therapy when this is not effective or not tolerated. Recently, selective laser trabeculoplasty (SLT) has been advocated as first-line therapy, and "minimally invasive glaucoma surgery" (MIGS) has been developed as safer and less traumatic surgical intervention for patients with glaucoma. Schlemm's canal surgery has emerged as one of the approaches with the most favorable risk-benefit profile for glaucoma patients in need of cataract surgery. However, despite the promising results, use of MIGS in Italy has been extremely low. We aimed to investigate the reasons of the lower-than-expected use of Schlemm's canal-based MIGS devices in Italy, share our perspective on their potential place in therapy, and give practical suggestions to improve the management of glaucoma patients.

Transscleral versus endoscopic cyclophotocoagulation outcomes for refractory glaucoma

OBJECTIVES

Evaluate the efficacy of transscleral cyclophotocoagulation versus endoscopic cyclophotocoagulation to reduce intraocular pressure.

METHODS

A retrospective, non-randomized cohort study with 1 year of follow-up included 62 eyes of 62 refractory glaucoma patients who underwent transscleral cyclophotocoagulation or endoscopic cyclophotocoagulation.

RESULTS

Thirty-two patients were enrolled in transscleral cyclophotocoagulation group and 30 patients in endoscopic cyclophotocoagulation group, and the follow-up period was 1 year. The mean preoperative intraocular pressure was 35.6 ± 12.9 mm Hg in the transscleral cyclophotocoagulation group and 31.8 ± 8.8 mm Hg in the endoscopic cyclophotocoagulation group without significant difference (p = 0.18). When we compare both groups, there was no difference at 1 month (p = 0.46) and 3 months (p = 0.21) after surgery. However, there was a statistically significant difference at month 6 (p = 0.0055) and 1 year (p = 0.0019), finding lower intraocular pressure in the transscleral cyclophotocoagulation group. Cumulative success for intraocular pressure <21 mm Hg was 93.8% in transscleral cyclophotocoagulation group and 83.3% in endoscopic cyclophotocoagulation group after 1 year (p = 0.2). For intraocular pressure <18 mm Hg, the success rate was 78.1% in transscleral cyclophotocoagulation group and 63.3% in endoscopic cyclophotocoagulation group (p = 0.06), and for intraocular pressure <16 mm Hg, the success rate was 62.5% in transscleral cyclophotocoagulation group and 43.3% in endoscopic cyclophotocoagulation group (p = 0.02). Hypotony (p = 0.01) and vision loss of two lines (p = 0.01) were statistically significant lower in endoscopic cyclophotocoagulation group.

CONCLUSION

This study demonstrates that both transscleral cyclophotocoagulation and endoscopic cyclophotocoagulation are effective at decreasing intraocular pressure. However, transscleral cyclophotocoagulation is related to more complications than endoscopic cyclophotocoagulation, whereas endoscopic cyclophotocoagulation shows lower intraocular pressure decrease than transscleral cyclophotocoagulation.

Comparison of ExPress Implantation and Partial Deep Sclerectomy Combined with ExPress Implantation and Simultaneous Phacoemulsification

Background

To compare the effectiveness and safety profile of ExPress implantation versus partial deep sclerectomy combined with ExPress implantation and simultaneous phacoemulsification.

Patients and Methods

A prospective, randomized control study with 24-month follow-up was performed. 114 eyes were included, of which 42 eyes underwent phacoemulsification with simultaneous implantation of the Ex-Press device (ExPress), and deep sclerectomy with phacoemulsification and simultaneous implantation of the Ex-Press device (DS-ExPress) was performed in 72 eyes. The main outcome measures were intraocular pressure (IOP), corrected distance visual acuity (CDVA), the number of antiglaucoma medications, and the rate of complications. Surgical success was defined as complete (without antiglaucoma medications) with IOP ≤18 mmHg in criterion A, IOP ≤16 mmHg in criterion B, and IOP ≤12 mmHg in criterion C. Satisfactory success was defined as the same IOP levels for individual criteria with a maximum of 2 antiglaucoma medications.

Results

Before the procedure, mean IOP in the ExPress group was 17.5 ± 4.7 mmHg; after 24 months, it decreased by 13% to 16.0 ± 3.0 mmHg (P < 0.05). In the DS-ExPress group, mean IOP reduced from 16.3 ± 4.4 mmHg to 14.3 ± 3.3 mmHg (P < 0.05), which was a 9% reduction compared to the initial value. In the DS-ExPress group, 65.9% of the patients did not use topical pharmacotherapy, and the same is true for 29.2% of the ExPress group (P=0.004).

Conclusions

This modification is efficient in surgical treatment of glaucoma, especially when very low postoperative IOP is needed. A less amount of antiglaucoma medicines are needed.

Reoperation rates after Ex-PRESS versus trabeculectomy for primary open-angle or normal-tension glaucoma: a national database study in Japan

OBJECTIVE

To compare reoperation rates between Ex-PRESS implantation and trabeculectomy.

METHODS

We performed a retrospective cohort study using a national inpatient database in Japan. Patients aged 18-85 years with primary open-angle glaucoma or normal-tension glaucoma who underwent Ex-PRESS or trabeculectomy from 2010 to 2017 were included. We compared the reoperation rates between Ex-PRESS and trabeculectomy using mixed effects cox regression models. Covariates were sex, age, diabetes mellitus, simultaneous cataract surgery, ocular surgical history, and annual hospital volume for glaucoma surgery. Furthermore, we conducted propensity score (PS) matching and instrumental variable (IV) analyses to confirm the results of the conventional cox regression. We also compared total hospitalisation costs between the two treatments in the PS-matched groups.

RESULTS

In total, 1027 eyes underwent Ex-PRESS and 6910 eyes underwent trabeculectomy. The reoperation rates were 7.6% and 5.8% in the Ex-PRESS and trabeculectomy groups, respectively. The most frequently performed type of reoperation was trabeculectomy in both groups. The mixed effects cox regression showed that Ex-PRESS had significantly higher reoperation rates than trabeculectomy [adjusted hazard ratio (aHR), 1.72; 95% confidence interval (CI), 1.31-2.25; p < 0.001]. The PS and IV analyses also showed similar results (for PS analysis: aHR, 2.13; 95% CI, 1.45-3.13; p < 0.001; for IV analysis: aHR, 2.26; 95% CI, 1.05-4.85; p = 0.037). The total hospitalisation cost of Ex-PRESS (US$7076) was significantly greater than that of trabeculectomy (US$6223) (p < 0.001).

CONCLUSION

Ex-PRESS implantation had significantly higher reoperation rates and greater cost than trabeculectomy.

Treatment Outcomes in the Primary Tube Versus Trabeculectomy Study after 3 Years of Follow-up

PURPOSE

To report 3-year results of the Primary Tube Versus Trabeculectomy (PTVT) Study.

DESIGN

Unmasked multicenter randomized clinical trial.

PARTICIPANTS

Two hundred forty-two eyes of 242 patients with medically uncontrolled glaucoma and no previous incisional ocular surgery, including 125 in the tube group and 117 in the trabeculectomy group.

METHODS

Patients were enrolled at 16 clinical centers and were assigned randomly 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

The primary outcome measure was the rate of surgical failure, defined as intraocular pressure (IOP) of more than 21 mmHg or reduced less than 20% from baseline, IOP of 5 mmHg or less, reoperation for glaucoma, or loss of light perception vision. Secondary outcome measures included IOP, glaucoma medical therapy, visual acuity, and surgical complications.

RESULTS

The cumulative probability of failure after 3 years of follow-up was 33% in the tube group and 28% in the trabeculectomy group (P = 0.17; hazard ratio, 1.39; 95% confidence interval, 0.9-2.2). Mean ± standard deviation IOP was 14.0±4.2 mmHg in the tube group and 12.1±4.8 mmHg in the trabeculectomy group at 3 years (P = 0.008), and the number of glaucoma medications was 2.1±1.4 in the tube group and 1.2±1.5 in the trabeculectomy group (P < 0.001). Serious complications requiring reoperation or producing loss of 2 or more Snellen lines developed in 3 patients (2%) in the tube group and 9 patients (8%) in the trabeculectomy group (P = 0.11).

CONCLUSIONS

There was no significant difference in the rate of surgical failure between the 2 surgical procedures at 3 years. Trabeculectomy with MMC achieved lower IOP with use of fewer glaucoma medications compared with tube shunt surgery after 3 years of follow-up in the PTVT Study. Serious complications producing vision loss or requiring reoperation occurred with similar frequency after both surgical procedures.

Ex-PRESS implantation for different types of glaucoma

AIM

To evaluate the clinical results, efficacy and safety of Ex-PRESS P200 glaucoma shunt implant in different types of medically uncontrolled glaucoma.

METHODS

The study included 31 eyes of 31 patients that were unresponsive to medical antiglaucomatous therapy in whom Ex-PRESS P200 glaucoma shunt implantation was performed. The demographic characteristics of the patients, type of glaucoma, complete ocular examination results, number of antiglaucomatous drugs before and after surgery, early and late complications of surgery, additional surgical and nonsurgical medical interventions, and success rates were investigated from the patients' files, retrospectively.

RESULTS

The mean postoperative follow-up time was 16.4±7.5mo. The preoperative mean corrected intraocular pressure (IOP) was 28.7±10.3 mm Hg and postoperative mean corrected IOP was 15.3±5.2 mm Hg (P<0.05) at the last visit. The mean IOP reduction was 39.9% when the preoperative and postoperative values of the last visits were compared. The average number of antiglaucomatous drug use decreased from 3.9±0.3 to 1.7±1.7 postoperatively (P<0.05). The use of antiglaucomatous medications at the last visit was more than in other studies in the literature. The most common complication was conjunctival leakage, which was seen in 7 patients. Other early complications were iris touch, intravitreal hemorrhage, hyphema, choroidal effusion, early transient hypotonia and corneal edema. One of the late complications was endophthalmitis which was seen in one case 6mo after the operation, and the other late complication was opacification of the cornea in one patient. Twelve additional surgical operations associated to Ex-PRESS surgery and 3 bleb needling have done. At the last visit, the complete success rate was 32.3% and the qualified success rate was 77.5% in all patients.

CONCLUSION

Ex-PRESS P200 glaucoma shunt implantation may be an effective procedure for medically uncontrolled glaucoma with significantly lower use of antiglaucomatous medications.

Efficacy of Ologen matrix implant in Ahmed Glaucoma Valve Implantation

To determine the efficacy and safety of the Ologen collagen matrix adjunctive to Ahmed valve surgery. A randomized prospective multicentre clinical trial involving 58 patients that were followed for one year. Conventional surgery with Ahmed valve was performed in 31 eyes (Control group/CG) and in 27 Ologen (Ologen group/OG) was placed over the valve's plate. Baseline data: age, corneal thickness, intraocular pressure(IOP) and antiglaucoma medications.Postoperative data (days 1, 7 and months 1, 3, 6 and 12): IOP, antiglaucoma medications, visual acuity and complications were recorded. Frequency of hypertensive phase, complete and qualified success and survival rate were studied. No differences were found between CG and OG in the baseline data. The only difference between groups was a significantly lower IOP at day 1. No other differences were found in the follow-up between groups. Hypertensive phase (56%CG and 55%OG, p = 0,947), complete success 28,6%CG and 30,4%OG (p = 0,88) and qualified success 96,4% and 95,9%(p = 0,794). Survival rates at 1 year were 76,7%(CG) and 69,2%(OG)(p = 0,531). 38,7% of patients in the CG suffered some complication during follow-up and 61,5% in OG(p = 0,086). Ologen does not increase safety or efficacy in Ahmed valve surgery at one-year follow-up. This is the first study that shows no benefit of Ologen adjunctive to this surgery.

Long-Term Functional Outcomes of Glaucoma Tube Shunt Revision Surgery

PURPOSE

To characterize long-term outcomes of tube shunt revision surgeries and identify factors associated with their failure.

DESIGN

Retrospective chart review.

PARTICIPANTS

One eye from each of 179 patients who underwent tube shunt revision surgery at the Wilmer Eye Institute between 2004 and 2015 with a minimum follow-up of 6 weeks.

METHODS

Eligible eyes were identified from billing records and data related to their care were extracted from electronic medical records. Eyes were analyzed in aggregate and by indication for revision, including hypotony, high intraocular pressure (IOP), tube reposition, and tube exposure.

MAIN OUTCOME MEASURES

Surgical failure, defined as a need for further tube shunt revision or other glaucoma surgery, unsatisfactory IOP at last follow-up, or both. Secondary outcomes included postoperative infection and functional visual impairment.

RESULTS

With a median follow-up of 4.2 years, 126 failures occurred among 179 eyes. By Kaplan-Meier analysis, the cumulative rates of surgical failure at 1, 2, and 5 years after revision were 49%, 59%, and 74%, respectively. Most revision failures (105/126) were the result of the need for additional surgery, whereas 11 eyes showed IOP above target levels and 10 eyes showed dysfunctionally low IOP at the last follow-up. Factors associated with failure in a stepwise regression model were revision for hypotony (hazard ratio [HR], 6.79; P = 0.002), different surgeons performing the original and revision surgeries (HR, 2.80; P = 0.002), longer duration of symptoms before revision (P = 0.01), revision of a right eye (HR, 1.92; P = 0.03), and presumed preoperative infection (HR, 2.47; P = 0.04). In univariate analysis, success varied significantly by prior surgeon (P = 0.01), but not by revision surgeon. There was a 16% cumulative incidence of postoperative infection, with the highest risk in those with presumed preoperative infections (P = 0.01) and in persons of non-African, non-European derivation (P = 0.03).

CONCLUSIONS

The estimated rate of failure of tube shunt revision is 75% by 5 years, most often because of a need for further surgery. The major potentially modifiable feature associated with success is tube shunt revision being performed by the original surgeon.

XEN Gel Implant: a new surgical approach in glaucoma

INTRODUCTION

Glaucoma is a leading cause of blindness worldwide. Intraocular pressure (IOP) lowering is the only effective treatment strategy. Traditional glaucoma surgeries are generally considered to be unpredictable and associated with a high rate of complications. This has led to the development of a novel XEN Gel Implant, a type of minimally invasive glaucoma surgery (MIGS), lowering the IOP without extensive surgical dissection.

AREAS COVERED

A literature search was undertaken on PubMed using the terms XEN glaucoma, gelatin microstent, and MIGS. All the articles and case reports on XEN Gel Implant and selected articles on MIGS were studied and reviewed. We have discussed the results of most studies on XEN Gel Implant related to its efficacy, safety and success.

EXPERT COMMENTARY

The XEN Gel Implant effectively lowers IOP and medication use, with a favorable safety profile. Long-term data on its success and cost-effectiveness are lacking. The studies have shown it to be without any serious adverse events and to have good safety profile encouraging future research on this novel implant. There is a need to correctly identify selection criteria for patients, who would benefit the most from the XEN Gel Implant.

Postoperative Endophthalmitis: A Review of Risk Factors, Prophylaxis, Incidence, Microbiology, Treatment, and Outcomes

Postoperative endophthalmitis is one of the most feared complications of intraocular surgery. The most common types of intraocular surgeries performed worldwide are cataract extraction, glaucoma drainage implants/trabeculectomy, and pars plana vitrectomy. This review will focus on the clinical features, risk factors, prophylaxis, and treatment of endophthalmitis in these three main intraocular surgeries.

Long-term efficacy and safety of ExPress implantation for treatment of open angle glaucoma

AIM

To compare the long-term efficacy and safety of ExPress implantation and standard trabeculectomy in patients with primary open angle glaucoma (POAG).

METHODS

In this retrospective study, we compared 17 eyes treated by ExPress implantation with 23 eyes treated by trabeculectomy. Efficacy was assessed according to the relevant intraocular pressure (IOP) values and success rates during the first year of follow-up. Postoperative corneal endothelial cell loss was also compared.

RESULTS

The number of antiglaucoma medications and the IOP reduction were similar between the 2 groups during the follow-up period. Although the mean IOP was similar, the IOP-fluctuation rate during the early postoperative period was significantly lower in the ExPress group than in the trabeculectomy group (P=0.038). A Kaplan-Meier survival curve analysis showed no significant success-rate difference between the groups (P=0.810). The corneal endothelial cell loss rate, moreover, was significantly lower in the ExPress group (P=0.05).

CONCLUSION

ExPress implantation compared with trabeculectomy showed similar IOP-reduction and success rates along with lower IOP fluctuation and endothelial cell loss rates. For this reason, it can be considered to be the treatment of choice for patients with advanced glaucoma or low corneal endothelial cell density.

Microinvasive Glaucoma Surgery: An Evidence-Based Assessment

Introduction

The advent of Microinvasive Glaucoma Surgery (MIGS) offers a novel approach in the treatment of glaucoma with the number of procedures developing at an exciting pace.

Areas Covered

MIGS procedures aim to lower intraocular pressure (IOP) via four mechanisms: (1) increasing trabecular outflow, (2) increasing outflow via suprachoroidal shunts, (3) reducing aqueous production, and (4) subconjunctival filtration. A comprehensive search for published studies for each Microinvasive Glaucoma Surgery (MIGS) device or procedure was undertaken using the electronic database PubMed. Search terms included 'minimally invasive glaucoma surgery', 'microincisional glaucoma surgery', and 'microinvasive glaucoma surgery'. A manual search for each device or procedure was also performed. After review, randomized control trials and prospective studies were preferentially included.

Expert Opinion

These procedures offer several benefits: an improved safety profile allowing for intervention in earlier stages of glaucoma, combination with cataract surgery, and decreased dependence on patient compliance with topical agents. Established MIGS procedures have proven efficacy and more recent devices and procedures show promising results. Despite this, further study is needed to assess the long term IOP-lowering effectiveness of these procedures. Particularly, rigorous study with more randomized control trials and head-to-head comparisons would allow for better informed clinical and surgical decision-making. MIGS offers new solutions for glaucoma treatment.

Same-site Trabeculectomy Revision for Failed Trabeculectomy: Outcomes and Risk Factors for Failure

PURPOSE

To evaluate long-term tonometric outcomes of same-site trabeculectomy revision with mitomycin C (MMC) after failure of an initial trabeculectomy, and to identify risk factors for failure in patients with open-angle glaucoma.

DESIGN

Retrospective cohort study.

METHODS

One-hundred and seventeen patients (130 eyes) with primary open-angle, pseudoexfoliation, or pigmentary glaucoma, who failed a first trabeculectomy and who were ≥40 years of age at the time of same-site trabeculectomy revision, were included. Three levels of success criteria were defined: (A) intraocular pressure (IOP) ≤18 mm Hg and IOP reduction of 20%; (B) IOP ≤15 mm Hg and IOP reduction of 25%; and (C) IOP ≤12 mm Hg and IOP reduction of 30%. The primary outcome was the qualified Kaplan-Meier success rate (with or without medications) for each criterion. Cox multivariate regression analysis was used to identify risk factors for failure.

RESULTS

The success rates (± standard error) at the first, third, and fifth years of follow-up for criterion A were 69.7% (± 4.1%), 58.2% (± 4.6%), and 51.1% (± 5.0%); for criterion B these were 60.9% (± 4.4%), 47.8% (± 4.7%), and 44.0 (± 4.8%); and for criterion C, 44.6% (± 4.5%), 29.7% (± 4.4%), and 25.8% (± 4.3%). Mean follow-up was 5.2 (± 3.6) years. A time interval between the first and the same-site trabeculectomy revision of <3 years, worse baseline visual acuity, and dyslipidemia were significant risk factors for failure.

CONCLUSIONS

Given the long-term tonometric success rates along with significant medication reduction, same-site trabeculectomy revision with MMC should be considered as a viable option to achieve reasonable IOP targets after a first failed trabeculectomy in open-angle glaucoma patients.

Primary open-angle glaucoma

Glaucoma is an optic neuropathy that is characterized by the progressive degeneration of the optic nerve, leading to visual impairment. Glaucoma is the main cause of irreversible blindness worldwide, but typically remains asymptomatic until very severe. Open-angle glaucoma comprises the majority of cases in the United States and western Europe, of which, primary open-angle glaucoma (POAG) is the most common type. By contrast, in China and other Asian countries, angle-closure glaucoma is highly prevalent. These two types of glaucoma are characterized based on the anatomic configuration of the aqueous humour outflow pathway. The pathophysiology of POAG is not well understood, but it is an optic neuropathy that is thought to be associated with intraocular pressure (IOP)-related damage to the optic nerve head and resultant loss of retinal ganglion cells (RGCs). POAG is generally diagnosed during routine eye examination, which includes fundoscopic evaluation and visual field assessment (using perimetry). An increase in IOP, measured by tonometry, is not essential for diagnosis. Management of POAG includes topical drug therapies and surgery to reduce IOP, although new therapies targeting neuroprotection of RGCs and axonal regeneration are under development.

[Revision surgery in episcleral glaucoma drainage devices]

Episcleral glaucoma drainage devices (e.g., Ahmed or Baerveldt drainage device) are often used at a late stage in the care of glaucoma patients. At this stage other surgical techniques, such as trabeculectomy or viscocanaloplasty, have failed. However, the trend towards earlier implant surgery is supported by large randomized trials. Physicians should be aware of typical complications and, if possible, these should already be avoided by careful surgical technique. In this review article, we focus on postoperative hypotension, postoperative pressure increases, implant exposure, and possible corneal decompensation.

Managing Drawbacks in Unconventional Successful Glaucoma Surgery: A Case Report of Stent Exposure

Traditional options in managing failed trabeculectomy (bleb needling, revision, additional incisional surgery and tube surgery) have a relatively high failure and complication rate. The use of microinvasive glaucoma surgery (MIGS) has generally been reserved to mild to moderate glaucoma cases, proving good safety profiles but significant limitations in terms of efficacy. We describe a patient who underwent MIGS (XEN Aquesys subconjunctival shunt implantation) after a prior failed trabeculectomy. After the surgery, the IOP was well controlled but as the stent was close to an area of scarred conjunctiva of the previous trabeculectomy, it became partially exposed. As a complete success was achieved, we decided to remove the conjunctiva over the exposed area and replace it by an amniotic membrane transplantation and a conjunctiva autograft. Six months after surgery, the unmedicated IOP is still well controlled with complete visual acuity recovery.

One Year of Glaucoma Research in Review-2013 to 2014

PURPOSE

The purpose of this study was to provide the practicing clinical ophthalmologist with an update on relevant glaucoma literature published from 2013 to 2014.

DESIGN

This study is a literature review.

METHODS

The authors conducted a 1-year (October 1, 2013, to September 30, 2014) English-language glaucoma literature search on PubMed of articles containing "glaucoma" or "glaucomatous" with title/abstract as a filter. Medical subject headings filtered searching was not performed because of the newness of the reviewed material.

RESULTS

Literature search yielded 2314 articles, after which we excluded reviews and letters to the editor. We highlighted articles featuring new or updated approaches to the pathophysiology, diagnosis, or treatment of glaucoma and gave preference to human research.

CONCLUSIONS

This review features literature that is of interest to ophthalmologists in practice and also highlights studies that may provide insight on future developments applicable to clinical ophthalmology.

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.

Is There a Need for New Surgical Procedures for Glaucoma? Yes!

The only method to slow or stop progressive damage caused by glaucoma, the leading cause of irreversible blindness, definitively shown to be effective, is lowering intraocular pressure, though there is also evidence that stabilizing the pressure may be beneficial. Performing surgery on the eye has proven effective in some cases, using various techniques, though with variable frequencies of success (stabilization of the disease) and various frequencies and severities of complications. Surgery offers the great advantage of longer duration of action than medicinal treatments presently available, and, also, of lessening the need of the patient to be faithful using suggested medications. There is a need to develop surgical procedures which will be effective in 1) lowering or stabilizing intraocular pressure in a way most likely to prevent glaucomatous deterioration, 2) causing the fewest and least severe problems, and 3) being the most economical. Recent efforts in this regard are promising, but not yet proven superior to well-performed trabeculectomy, itself an evolving procedure.

[Canaloplasty after trabeculectomy]

BACKGROUND

Canaloplasty after failed trabeculectomy is an operation with differing individual surgical situations, which depend on the extent of scarring in the preexisting bleb area and on the site of the fistula in the chamber angle itself.

OBJECTIVE

The results of 18 cases and the surgical technique are presented.