Complications after CyPass® Micro-Stent explantation: a case series.

PURPOSE: To describe the in toto explantation of the CyPass® Micro-Stent and its conceivable complications. METHODS: This is a case series of eighteen eyes from fourteen patients who underwent CyPass® Micro-Stent implantation due to mild to moderate glaucoma and who subsequently suffered from loss of endothelial cell density. Consequently, the CyPass® Micro-Stent was in toto explanted. The surgical procedure and its complications are described and compared with trimming of the CyPass® Micro-Stent. RESULTS: A postoperative hyphema was developed in 8 of the 18 eyes. In four of them the hyphema was self-limiting, while in two patients an anterior chamber irrigation was necessary. One patient suffered from a severe intracameral bleeding and iridodialysis during explantation, so that the base of the iris had to be scleral fixated. The remaining explantations were without complications. CONCLUSION: Dealing with implanted CyPass® Micro-Stents poses a challenge for ophthalmic surgeons. An in toto removal can be traumatic, since the CyPass stent often is fibrotic encapsulated and fused with the surrounding tissue. Alternatively, trimming of the CyPass is also a viable option to avoid further endothelial damage. Reported complications of CyPass trimming are consistent with those that can occur after explantation. Further data on the development of the endothelial cells after trimming or explantation are not yet available. Therefore, it remains open whether trimming of the CyPass, in contrast to complete removal, carries the risk of further endothelial cell loss.

A comparative study of cystoid macula edema following glaucoma drainage device surgery versus trabeculectomy.

PURPOSE: To assess and compare the risk for development of cystoid macula edema (CME) after glaucoma drainage device (GDD) implantation versus conventional trabeculectomy with mitomycin (trab) for glaucoma. METHODS: Retrospective review of consecutive patients receiving trab or GDD implantation between 2016 and 2018. Inclusion criteria were availability of pre- and postoperative spectral domain optical coherence tomography (SD-OCT) of the macula. SD-OCT images were evaluated for presence of CME qualitatively, central subfield thickness (CST) and macular volume (MV). RESULTS: 73 eyes could be included, 42 received trab and 31 GDD surgery. Eyes receiving trab on average had 0.8 ± 0.8 previous intraocular operations, while eyes with GDD implantation had 3.1 ± 1.9 (p < 0.001). Occurrence of postoperative CME was significantly more frequent after GDD implantation (6 out of 31 (19.4%)) than after trab (2 out of 42 eyes = 4.8%), (p = 0.049). Mean preoperative CST as well as MV was comparable in both groups (CST before trab: 282.7 ± 23.0 µm, CST before GDD 284.2 ± 27.3 µm, p = 0.287; MV before trab: 7.8 ± 1.1 mm3, MV before GDD: 8.0 ± 0.8mm3, p = 0.305). Mean postoperative CST and MV were significantly higher after GDD (CST 338.5 ± 129.3 µm, MV 8.8 ± 2.6 mm3) than after trabeculectomy (CST 290.6 ± 60.2 µm, p = 0.038; MV 7.8 ± 1.2mm3, p = 0.039). CONCLUSIONS: In real-life conditions, GDD surgery seems to be associated with a higher risk to develop CME when compared to conventional trabeculectomy. This information may be helpful for glaucoma surgeons to advise the patients on postoperative risks of surgery.

Concurrent ciliary body detachment in patients presenting with serous choroidal detachment following glaucoma surgery.

PURPOSE: To examine the rate of ciliary body detachment in patients with choroidal detachment following glaucoma surgery and its effect on the clinical course, management, and prognosis. METHODS: A prospective observational case-series study. Patients with choroidal detachment following glaucoma surgery in 2018-2019 were included. All underwent complete ophthalmological examination and ultrasound biomicroscopy for evaluation of the presence and extent of ciliary body detachment. Follow-up examinations including ultrasound biomicroscopy scans were performed at 1 week, 1 month, 3 months, and 6 months. RESULTS: Eight patients (8 eyes) were enrolled, 4 male and 4 female, of mean age 72 years (range 60-83). Five patients underwent trabeculectomy with mitomycin C (0.02%), which was combined with phacoemulsification cataract extraction in one; two underwent Ahmed glaucoma valve implantations, and one underwent ab-interno Xen45 gel stent implantation with mitomycin C (0.02%). The mean intraocular pressure was 26.0 ± 7.65 mmHg preoperatively, dropping to 6.9 ± 2.64 mmHg on first postoperative day one. Mean time from surgery to diagnosis of choroidal detachment was 11.6 ± 5.73 days. Ciliary body detachment was identified by ultrasound biomicroscopy in all patients, ranging between one and four quadrants. All patients were treated with topical steroids and cycloplegics; three (37.5%) received oral steroids. No surgical intervention for the choroidal or ciliary body detachments was indicated. CONCLUSIONS: In this real-world prospective study, concurrent ciliary body detachment was identified in all patients who presented with choroidal detachment following glaucoma surgery. This observation may deepen our understanding of the mechanism underlying the hypotony that is often seen after glaucoma surgery.

Risk factors and management of choroidal effusions.

PURPOSE OF REVIEW: Choroidal effusions are recognized as a common early postoperative complication of glaucoma surgery, and although often benign, they may cause significant ocular morbidity. This article aims to summarize current research on the risk factors and management of choroidal effusions. RECENT FINDINGS: Glaucoma drainage device (GDD) implantation and trabeculectomy are the most commonly performed surgeries for the management of moderate to severe glaucoma. Common postoperative complications of these procedures include hypotony and the development of choroidal effusions. Choroidal effusions have recently been associated with the oral administration of certain drugs, including select monoclonal antibody, antiseizure and bisphosphonate medications. Risk factors for effusion development include specific patient characteristics such as pseudoexfoliative glaucoma, older age and hypertension. Although choroidal effusions typically resolve with medical therapy alone, surgical intervention may be required. Various methods of surgical intervention, such as surgical drainage or GDD tube ligation, can be utilized to treat choroidal effusions when conservative management with medical treatment fails, but themselves carry alternative risks that must be considered. SUMMARY: Minimizing the incidence and duration of hypotony following ophthalmic surgery and careful monitoring of patients starting certain oral medications are important in limiting the occurrence of choroidal effusions. Risk factors for choroidal effusions have been recently identified in the literature. A better understanding of these risk factors, as well as the outcomes of choroidal effusion management, can help to reduce the occurrence of effusions overall and minimize ocular morbidity.

Outcomes of the Aurolab aqueous drainage implant and trabeculectomy with mitomycin C in iridocorneal endothelial syndrome.

PURPOSE: To compare the surgical outcomes of the Aurolab aqueous drainage implant (AADI) and trabeculectomy with mitomycin C (MMC) in patients with glaucoma secondary to iridocorneal endothelial (ICE) syndrome. MATERIALS AND METHODS: This retrospective comparative case series included 41 eyes of 41 patients with ICE syndrome and glaucoma who underwent either a trabeculectomy with MMC (n = 20) or AADI surgery (n = 21) with a minimum of 2 years follow-up. Outcome measures included intraocular pressure (IOP), the use of glaucoma medications, visual acuity, additional surgical interventions, and surgical complications. Surgical failure was defined as IOP > 21 mmHg or reduced < 20% from baseline, IOP ≤ 5 mmHg, reoperation for glaucoma or a complication, or loss of light perception vision. RESULTS: The cumulative probability of failure at 2 years was 50% in the trabeculectomy group (95%CI = 31-83%) and 24% in the AADI group (95%CI = 11-48%) (p = 0.09). The IOP was consistently lower in the AADI group compared with the trabeculectomy group at 6 months and thereafter. Surgical complications occurred in 13 eyes (65%) in the trabeculectomy group and 12 eyes (57%) in the AADI group (p = 0.71). Reoperations for glaucoma or complications were performed in 12 eyes (60%) in the trabeculectomy group and 5 patients (24%) in the tube group (p = 0.06). Cox proportional hazards showed that AADI had a 53% lower risk of failure at 2 years (p = 0.18; HR = 0.47; 95%CI = 0.16-1.40). CONCLUSION: AADI surgery achieved lower mean IOPs than trabeculectomy with MMC in managing glaucoma secondary to ICE syndrome. A trend toward lower rates of surgical failure and reoperations for glaucoma and complications was observed following AADI placement compared with trabeculectomy with MMC in eyes with ICE syndrome.

Risk factors for ocular hypotony after XEN Gel Stent implantation.

PURPOSE: To investigate the incidence of postoperative hypotony, and risk factors for the development of hypotony in eyes who had undergone XEN Gel Stent implantation. METHODS: In this retrospective, single-centre case series, medical records of 170 consecutive eyes who had undergone XEN Gel Stent implantation with or without simultaneous phacoemulsification for primary or secondary open angle glaucoma were analysed. Primary outcome parameters were the incidence of postoperative hypotony and potential risk factors for its development, and secondary parameters were pre- and postoperative visual acuity, intraocular pressure (IOP), and number of IOP-lowering eye drops. RESULTS: Postoperative hypotony ≤ 6 mmHg occurred in 57% of eyes. Hypotony was without complications in 70.1%, 13.4% had transient complications with spontaneous resolution, and 16.5% had complications requiring treatment. Mean visual acuity logMAR before surgery accounted for 0.47 ± 0.46 in all eyes and 0.47 ± 0.48 at the 4-week visit. There was no significant difference of BCVA in the group of eyes with and without postoperative hypotony before and after surgery. The mean IOP before surgery was 24.6 ± 8.4 mmHg and decreased significantly to 18.4 ± 10.2 after 4 weeks. Eyes with an axial length over 24.3 mm had a threefold increased risk for postoperative hypotony (OR 3.226, 95% confidence interval 1.121-9.279). This risk was decreased in eyes with simultaneous cataract surgery (OR 0.483, 95% confidence interval 0.258-0.903). CONCLUSION: In our sample, postoperative hypotony was a common complication after XEN Gel Stent implantation, but serious, persistent complications were rare. A longer axial length predisposes the eye for the development of hypotony.

XEN® implantation: an effective strategy to stop glaucoma progression despite prior minimally invasive glaucoma surgery.

PURPOSE: The aim of this study was to evaluate whether XEN® implantation is a reasonable and safe method to lower the intraocular pressure (IOP) and amount of medication for adult primary open-angle glaucoma (POAG) over a 3-year period. The influence of the type of anesthesia, previous glaucoma surgery, and postoperative interventions on the outcome were examined. METHODS: In this retrospective study, 96 eyes were included. XEN® implantation was performed as sole procedure under general (n = 86) or local anesthesia (n = 10). IOP and number of glaucoma medication were assessed preoperatively: day 1, week 6, month 3, 6, 12, 24, and 36. Further outcome parameters were Kaplan-Meier success rates, secondary intervention, and complication rates. RESULTS: IOP decreased from 20.7 ± 5.1 to 12.8 ± 2.5 mmHg at the 36-month follow-up (p < 0.001) and glaucoma therapy was reduced from 3.3 ± 0.8 to 1.2 ± 1.6 (36 months, p < 0.001). Transient postoperative hypotony was documented in 26 eyes (27.1%). General anesthesia resulted in a significant improvement of the survival rate compared to local anesthesia (77% vs. 50%, p = 0.044). Prior iStent inject®, Trabectome®, or SLT laser had no significant impact, such as filter bleb revision. The number of postoperative needlings had a significantly negative influence (p = 0.012). CONCLUSION: XEN® implantation effectively and significantly lowers the IOP and number of glaucoma therapy in POAG in the 36-month follow-up with a favorable profile of side effects and few complications. In case of IOP, general anesthesia has a significant positive influence on the survival rate, whereas prior SLT or MIGS does not have significant impact.

Foreign body reaction after CyPass® Micro-Stent implantation: a case series.

PURPOSE: To retrospectively assess the histopathological particularities of explanted CyPass® Micro-Stent of patients with significant loss of endothelial cell density. METHODS: This is a case series of fourteen eyes from eleven patients who underwent CyPass® Micro-Stent implantation due to mild to moderate glaucoma and who subsequently suffered from loss of endothelial cell density. Therefore, the explantation of the device was necessary. In addition to the retrospective evaluation of the intraocular pressure and the endothelial cell density at the time of implantation and explantation, every surgically removed implant was histologically examined and evaluated. RESULTS: Fourteen eyes of eleven patients were in total analysed. The patients-seven males and four females-had a mean age of 62.9 years. The average time between CyPass implantation and explantation was 3.7 years. Eight patients suffered from primary-open-angle glaucoma (POAG), while two patients had a pseudoexfoliation glaucoma (PXG) and one patient had low-pressure glaucoma. Ten of the patients were already pseudophakic before the CyPass implantation and four patients underwent previously glaucoma interventions. There was a significant reduction in the intraocular pressure from 18.57 ± 5.27 mmHg at the time of implantation to 14.78 ± 3.32 mmHg at the time of explantation (p = 0.037). The average endothelial cell density decreased from 1843.67 ± 421.81 to 932.92 ± 412.86/mm2 at the time of explantation (p < 0.01). The histological findings showed a fibrous obliteration of the CyPass accompanied by a chronic granulomatous inflammation with giant cell macrophages. Histologically, these findings were consistent with a foreign body granuloma. CONCLUSIONS: Implants made of polyimides such as the CyPass® Micro-Stent are considered to be biocompatible, but there is no guarantee not to be obliterated or encapsulated. This is the first case series that has detected a foreign body granuloma in multiple eyes after CyPass implantation. However, there is no connection with the type of glaucoma, the extent of previous operations or with the presence of a prolonged postoperative inflammatory reaction.

A case of mitomycin C toxicity after XEN gel stent implantation with the XEN air technique in a glaucoma patient.

BACKGROUND: To discuss the first case of mitomycin C (MMC) toxicity after XEN® gel stent implantation in a glaucoma patient, conducted using the XEN "air" technique with an ophthalmic viscosurgical device (OVD). CASE PRESENTATION: A 44-year-old Asian male presented with increased intraocular pressure (IOP; 52 mmHg) accompanied by keratic precipitates and an edematous cornea. He was diagnosed with uveitic glaucoma in the left eye, and the IOP was controlled with a topical anti-glaucoma agent. However, glaucoma progression was revealed by Humphrey visual field (HVF) and optical coherence tomography (OCT) examinations. The patient underwent uneventful XEN gel stent implantation using the XEN air technique and an MMC (0.02%, 0.1 mL) injection, with subconjunctival air and OVD injection provided prior to XEN implantation in the left eye. The patient exhibited a decreased IOP (11 mmHg), elevated bleb, and extensive subconjunctival hemorrhage on postoperative day 1. On postoperative day 18, diffuse conjunctival injection and a large avascular bleb was noticed around the XEN gel stent. The patient complained of severe eye pain and discomfort, suggestive of MMC toxicity, and the IOP was 12 mmHg. The patient was treated with a topical steroid and antibiotics tapered over a 6-month period. Finally, the toxicity was successfully controlled, with the IOP stabilizing at around 15 mmHg. CONCLUSIONS: Although significantly greater lowering of the IOP can be expected with the use of subconjunctival OVD injection and MMC during XEN gel stent implantation, a cautious approach and a longer monitoring period are required.

Spontaneous resolution of long-standing choroidal effusion after glaucoma drainage implant surgery without significant visual deterioration : a case report.

BACKGROUND: Choroidal effusion is a common complication of glaucoma surgery. Although most cases of choroidal effusions resolve spontaneously with observation or medical management alone as intraocular pressure normalizes, surgical drainage might be needed in severe or persistent cases. Herein, we report a case of spontaneous resolution of long-standing severe choroidal effusion after Ahmed glaucoma valve implantation. CASE PRESENTATION: An 85-year-old man with uncontrolled primary open-angle glaucoma and medical history of chronic kidney disease underwent uneventful Ahmed glaucoma valve implantation. On postoperative day 8, transient hypotony occurred, and large 360° peripheral choroidal detachments developed. Although the intraocular pressure increased to normal levels on postoperative day 15, choroidal effusion did not resolve. Fundus examination over 8 months showed that the large choroidal effusion persisted despite a well-controlled intraocular pressure. Laboratory test performed at preoperatively and follow-up period revealed persistently elevated potassium and creatinine levels. On postoperative 9 months, the lesion resolved spontaneously without any surgical intervention. We found that the patient's creatinine level was normalized, pre-existing hyperkalemia was corrected, and accordingly his general condition was improved. CONCLUSIONS: Considering the underlying medical condition may be helpful in patients with persistent choroidal effusion of an unclear etiology following glaucoma filtering surgery.

The effects of the first versus second glaucoma drainage implant surgery in patients with primary open-angle glaucoma.

BACKGROUND: To investigate the outcome of non-valved glaucoma drainage implant surgery (GDIS) in primary open-angle glaucoma (POAG) patients divided in the first GDI group (patients who underwent the first GDIS) and the second GDI group (patients who underwent the second GDIS because of the failed first GDIS). METHODS: Intraocular pressure (IOP), visual acuity (VA), visual field defect (VFD), medication score (MS), survival rate of GDIS, complications, and patient background was retrospectively analyzed. Two success criteria were set: Criteria (1) IOP reduction ≥ 20% and 5 < IOP ≤ 21, Criteria (2) IOP reduction ≥ 20% and 5 < IOP ≤ 14. RESULTS: There were 136 eyes of 109 patients in the first GDI group and 32 eyes of 27 patients in the second GDI group. In the first GDI group and II, mean preoperative IOP was 26.7 ± 6.7 mmHg and 23.7 ± 3.5 mmHg, respectively (P = 0.09). No statistically significant difference in postoperative IOP reduction was found between the two groups (P = 0.39). At 5-years postoperative, the Criteria 1 (Criteria 2) survival rate in the first GDI group and the second GDI group was 60.4% (31.7%) and 61.2% (25.6%), respectively (Criteria 1: hazard ratio [HR]: 0.64, 95% confidence interval [CI]: 0.30-1.35 [P = 0.24]; Criteria 2: HR: 0.81, 95% CI: 0.46-1.44, P = 0.48). No significant difference in VA, VFD change, MS, or complications was observed. Young patient age was the only significant factor for failure in the first GDI group (odds ratio: 0.95, 95% confidence interval: 0.91-1.00, P = 0.03). CONCLUSION: The second GDIS may be as effective as the first GDIS for IOP reduction in POAG patients, however, there is a high risk of failure in young-age patients and the surgery may be ineffective in eyes requiring Criteria 2.

Comparison of Aurolab Aqueous Drainage Implant with Ahmed Glaucoma Valve for Refractory Glaucoma: A Meta-Analysis.

BACKGROUND: Ahmed glaucoma valve (AGV) is a common surgical method for the treatment of refractory glaucoma.Aurolab aqueous drainage implant (AADI) is a novel surgical method which has been applied in clinical practice in recent years. OBJECTIVE: The purpose of this study was to compare the efficacy and safety of the AADI and the AGV for the treatment of refractory glaucoma. METHODS: We comprehensively searched four databases, including PubMed, Embase, Web of Science, and the Cochrane Library databases, selecting the relevant studies. The continuous variables, namely, intraocular pressure reduction (IOPR) and a reduction in antiglaucoma medication (AGMR), were pooled by the weighted mean differences (WMDs), and the dichotomous outcomes, including success rates and complications, were pooled by the odds ratio (OR). RESULTS: A total of 825 eyes from 820 patients from six studies were included. The WMDs of the IOPR between the AADI and the AGV implant were 0.58 (95% CI: 0.07-1.09) at 3 months, 0.44 (95% CI: 0.11-0.77) at 6 months, 2.20 (95% CI: 0.63-3.77) at 12 months, and 3.24 (95% CI: 1.73-4.75) at follow-up endpoint. Significant difference was detected between the two groups at any point in time. The WMDs of the AGMR between the AADI and the AGV implant were 0.87 (95% CI: 0.61-1.13) at 6 months, 1.04 (95% CI: 0.66-1.42) at 12 months, and 0.93 (95% CI: 0.52-1.34) at the follow-up endpoint; the differences reached statistical significance at any point in time. The pooled ORs comparing the AADI with the AGV were 3.64 (95% CI: 2.44-5.45) for the complete success rate and 1.72 (95% CI: 1.24-2.39) for qualified success rate; significant difference was detected between the two groups. There were no significant differences between the AADI and the AGV implant on the rates of adverse events. CONCLUSIONS: The AADI is more effective in both its surgical success rate and reducing IOP and AGM. And the two implants may have comparable incidences of adverse events.

Clinical outcomes of the PAUL® glaucoma implant: One-year results.

BACKGROUND: To report one-year outcomes from a single-centre cohort undergoing PAUL® Glaucoma Implant (PGI) surgery. METHODS: Retrospective review of patients undergoing PGI surgery at the University Eye Hospital Bonn, Germany, from April 2021 to September 2021. RESULTS: Forty-five eyes of 41 patients were included. Qualified and complete success rates (95% CI) were 95.6% (88.9%-100%) and 73.3% (60%-86.7%) for Criterion A (IOP ≤ 21 mmHg), 84.4% (73.3%-93.3%) and 74.4% (51.1%-80.0%) for Criterion B (IOP ≤ 18 mmHg), 62.2% (48.9%-75.6%) and 46.7% (31.2%-62.2%) for Criterion C (IOP ≤ 15 mmHg) and 26.7% (13.3%-40.0%) and 22.2% (11.1%-33.3%) for Criterion D (IOP ≤ 12 mmHg), respectively. Mean IOP decreased from 26.1 mmHg (7-48 mmHg) to 12.0 mmHg (3-24 mmHg) (reduction of 48.83%) after 12 months with a reduction of IOP-lowering agents from 0.5 (0-3). One eye (2.2%) needed an injection of viscoelastic due to significant hypotony with AC shallowing, and four eyes (8.9%) developed choroidal detachments due to hypotony which resolved without further interventions after 6 weeks. Three patients (6.7%) developed tube exposure which required conjunctival revision with an additional pericardial patch graft. An intraluminal prolene stent was removed in 19 eyes (42.2%) after a mean time period of 8.4 months (2-12 m). Mean IOP before the removal was 21.9 mmHg (12-38 mmHg) and decreased to 11.3 mmHg (6-16 mmHg). CONCLUSIONS: PGI surgery is an effective procedure for reducing IOP and pressure-lowering therapy. An intraluminal prolene stent impedes hypotony in the early postoperative phase and enables further IOP lowering without additional interventions during the postoperative course.

Incidence of Blepharoptosis After Pars Plana Baerveldt 350 Glaucoma Implant Surgery by a Single Surgeon.

PURPOSE: To investigate the incidence of postoperative blepharoptosis and clinical risk factors for blepharoptosis after pars plana Baerveldt 350 glaucoma implantation (BGI) by a single surgeon for refractory glaucoma. METHODS: Twenty-four patients (30 eyes) who underwent pars plana BGI for refractory glaucoma at Toyama University Hospital between November 2019 and February 2021 were included. Patients with a preoperative margin reflex distance-1 (MRD-1) of ≥2 mm were included in the study, and a decrease in MRD-1 of ≥2 mm at 6 months postoperatively was defined as blepharoptosis. RESULTS: The mean MRD-1 decreased significantly from 3.2 ± 0.6 mm preoperatively to 2.4 ± 1.1 postoperatively ( p < 0.01). Postoperative ptosis developed in 8 eyes (26.7%). A comparison of the ptosis (n = 8) and nonptosis (n = 22) groups showed a significant difference in the history and number of previous filtration surgeries ( p = 0.02 and p = 0.03, respectively). Those with previous filtration surgery had a higher risk of blepharoptosis after pars plana BGI compared with those without previous filtration surgery (OR: 6.43; 95% confidence interval: 1.03-40.26; p = 0.04). CONCLUSION: Pars plana BGI is a risk factor for postoperative blepharoptosis. Particular attention should be paid to eyes that have undergone previous filtration surgery.

Intraoperative primary partial occlusion of the PreserFlo MicroShunt to prevent initial postoperative hypotony.

PURPOSE: The aim of the underlying study was to present a new surgical method in PreserFlo MicroShunt surgery for glaucoma. A removable polyamide suture was placed into the lumen of the MicroShunt during implantation to prevent early postoperative hypotony. METHODS: Thirty-one patients undergoing stand-alone glaucoma surgery with implantation of a PreserFlo MicroShunt and an intraluminal occlusion were retrospectively reviewed and compared to a control group without occlusion. Inclusion criteria were diagnosis of primary open-angle glaucoma or secondary open-angle glaucoma due to pseudoexfoliation or pigment dispersion. Patients with a history of filtrating glaucoma surgery were excluded. RESULTS: IOP decreased from 26.9 ± 6.6 to 18.0 ± 9.5 mmHg at the first postoperative day after PreserFlo MicroShunt implantation. Postoperative removal of the occluding suture resulted in a mean IOP reduction in 11.1 ± 7.6 mmHg. Mean visual acuity was 0.43 ± 0.24 logMAR during the first postoperative examination. The interval with the occluding intraluminal suture in place varied from days to 2-3 weeks. Patients were followed up to 1 year. CONCLUSION: Implantation of a PreserFlo MicroShunt combined with an intraluminal suture prevented postoperative hypotony in all patients. Mean postoperative pressure was reduced despite the occluding suture in place.

Corneal endothelial cell loss after EX-PRESS surgery depends on site of insertion, cornea or trabecular meshwork.

PURPOSE: Previously, we reported that the Ex-press® shunt (EXP) was associated with more rapid reduction in corneal endothelial cells when inserted into the cornea rather than the trabecular meshwork (TM). We compared the reduction rate of corneal endothelial cells between the corneal insertion group and TM insertion group. METHODS: This was a retrospective study. We included patients who had undergone EXP surgery and were followed for > 5 years. We analyzed the corneal endothelial cell density (ECD) before and after EXP implantation. RESULTS: We included 25 patients in the corneal insertion group and 53 patients in the TM insertion group. One patient in the corneal insertion group developed bullous keratopathy. The ECD decreased significantly more rapidly in the corneal insertion group (p < 0.0001), in whom the mean ECD decreased from 2227 ± 443 to 1415 ± 573 cells/mm2 at 5 years with a mean 5-year survival rate of 64.9 ± 21.9%. By contrast, in the TM insertion group, the mean ECD decreased from 2356 ± 364 to 2124 ± 579 cells/mm2 at 5 years, and the mean 5-year survival rate was 89.3 ± 18.0%. The decrease rate of ECD was calculated as 8.3%/year in the corneal insertion group and 2.2%/year in the TM insertion group. CONCLUSIONS: Insertion into cornea is a risk factor for rapid ECD loss. The EXP should be inserted into the TM to preserve the corneal endothelial cells.

[Micro-invasive glaucoma surgery]. / Mikroinvazivnaya khirurgiya glaukomy.

Glaucoma is a severe, rapidly progressing disease that in the absence of proper treatment leads to blindness in 20% of patients. According to the World Glaucoma Association, this disease is the most socially significant in modern ophthalmology and requires searching for new and effective methods of treatment. This article presents the results of research and reviews on this issue, considers both conservative therapy and surgical methods of treatment, analyzes in detail modern methods of micro-invasive eye surgery actively used in clinical practice. The article also describes indications for a various types of interventions, as well as the effect achieved by them and the possible complications, and presents the conclusions about the possibility of using these procedures in wide clinical practice.

Corneal Endothelial Cell Density Loss after Glaucoma Surgery Alone or in Combination with Cataract Surgery: A Systematic Review and Meta-analysis.

TOPIC: Corneal endothelial cell density (ECD) loss after glaucoma surgery with or without cataract surgery. CLINICAL RELEVANCE: Corneal ECD loss may occur as the result of intraoperative surgical trauma in glaucoma surgery or postoperatively with chronic endothelial cell trauma or irritation. METHODS: Glaucoma filtration surgery or microinvasive glaucoma surgery (MIGS) in participants with ocular hypertension, primary and secondary open-angle glaucoma, normal-tension glaucoma, and angle-closure glaucoma were included. Electronic databases searched in December 2021 included MEDLINE, Embase, Cochrane Central Register of Controlled Trials, ClinicalTrials.gov, the International Prospective Register of Systematic Reviews, Food and Drug Administration (FDA) Premarket Approval, and FDA 510(k). RESULTS: A total of 39 studies were included in quantitative synthesis. Twelve months after suprachoroidal MIGS, mean ECD loss was 282 cells/mm2 (95% confidence interval [CI], 220-345; P < 0.00001; chi-square = 0.06; I2 = 0%; 2 studies; very low certainty). Mean ECD loss after Schlemm's canal implantable devices was 338 cells/mm2 (95% CI, 185-491; P < 0.0001; chi-square = 0.08; I2 = 0%; 2 studies; low certainty) at 12 months. Mean ECD loss was 64 cells/mm2 (95% CI, 21-107; P = 0.004; chi-square = 4.55; I2 = 0%; 6 studies; low certainty) after Schlemm's canal procedures (without implantable devices) at 12 months. At 12 months, the mean ECD loss after trabeculectomy was 33 cells/mm2 (95% CI, -38 to 105, P = 0.36, chi-square = 1.17; I2 = 0%; moderate certainty). At 12 months, mean ECD loss was 121 cells/mm2 (95% CI, 53-189; P = 0.0005; chi-square = 3.00; I2 = 0%; 5 studies; low certainty) after Express (Alcon) implantation. When compared with the control fellow eye, aqueous shunt surgery reduced ECD by 5.75% (95% CI, -0.93 to 12.43; P = 0.09, chi-square = 1.32; I2 = 0%; low certainty) and 8.11% ECD loss (95% CI, 0.06-16.16 P = 0.05; chi-square = 1.93; I2 = 48%) at 12 and 24 months, respectively. CONCLUSIONS: Overall, there is low certainty evidence to suggest that glaucoma surgery involving long-term implants has a greater extent of ECD loss than glaucoma filtration surgeries without the use of implants. The results of this review support follow-up beyond 36 months to assess ECD loss and corneal decompensation after implantation of glaucoma drainage implants.

Ultrastructural analysis of explanted CyPass microstents and correlation with clinical findings.

PURPOSE: The purpose of this study was to obtain insight into cellular processes after CyPass microstent implantation into the supraciliary space. With this knowledge, we expected to find some reason for surgical failure. METHODS: Nine CyPass microstents of 8 patients with primary open-angle glaucoma (n = 1), pseudoexfoliation glaucoma (n = 5), uveitic glaucoma (n = 1), and posttraumatic open-angle glaucoma (n = 1) were explanted due to recurrence of IOP elevation, corneal decompensation, or persistent hypotony. The explants were processed for light and transmission electron microscopy. RESULTS: Fibrotic material, consisting of collagen fibrils, microfibrils, pseudoexfoliation fibrils produced by activated fibroblasts, was detected in the stent lumen of 4/5 pseudoexfoliation glaucoma patients and also in posttraumatic open-angle glaucoma. Fibrotic material was also present on the outer surface and within fenestrations of the majority of stents. Complete absence of fibrotic reaction was noticed in 3 of 9 microstents. CONCLUSION: Although MIGS is known to be less invasive than conventional surgery, implants placed in the suprachoroidal space may be adversely affected by a fibrotic tissue reaction resulting in implant failure. Understanding mechanisms and risk factors leading to fibrotic scarring following antiglaucomatous surgery may help to develop novel strategies that improve surgical outcome.

The efficacy of XEN gel stent implantation in glaucoma: a systematic review and meta-analysis.

BACKGROUND: Xen is a device for minimally invasive glaucoma surgery, and is used to treat POAG, pseudoexfoliative or pigmentary glaucoma, as well as refractory glaucoma. The efficacy of XEN in treating glaucoma remains to be confirmed and clarified. Hence, we conducted a systematic review and meta-analysis to examine the efficacy and associated complication of XEN implantations. METHODS: We conducted a literature search in PubMed, EMBASE, the Cochrane Library of Systematic Reviews, Web of Science, China National Knowledge Infrastructure, WanFang and SinoMed databases to identify studies, published before May 15, 2021, which evaluated XEN in glaucoma, and parameters for measurements included intra-ocular pressure (IOP), number of anti-glaucoma medications (NOAM), and bleb needling rate. We compared the measurements of XEN-only procedure between phaco-XEN and trabeculectomy, and we also did sub-analysis based on time points, glaucoma types, ethnics, etc. Sensitivity analyses and publication bias were conducted for evaluating bias.This study followed the Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA 2020) reporting guideline. RESULTS: We identified 78 eligible studies, analysis revealed obvious IOP reduction after XEN stent implantation (SMD: 1.69, 95% CI 1.52 to 1.86, p value < 0.001) and NOAM reduction (SMD: 2.11, 95% CI 1.84 to 2.38, p value < 0.001). Sub-analysis showed no significant difference with respect to time points, ethnicities, and economic status. No significant difference was found between XEN treatment effect on POAG and PEXG eyes and between pseudo-phakic and phakic eyes. Also no significant difference was found between XEN and phaco-XEN surgery in terms of IOP after surgery (SMD: -0.01, 95% CI -0.09 to 0.08, p value 0.894). However, NOAM (after publication bias correction) and bleb needling rate (RR: 1.45, 95% CI 1.06to 1.99, p value 0.019) were lower in phaco-XEN group compared to XEN only group. Compared to trabeculectomy, XEN implantation had similar after-surgery IOP, however bleb needling rate (RR: 2.42, 95% CI 1.33 to 4.43, p value 0.004) was higher. CONCLUSION: Our results confirmed that XEN is effective in lowering both IOP and NOAM till 48 months after surgery. It is noteworthy that XEN implantation leads to higher needling rate, compared to phaco-XEN or trabeculectomy. Further research, studying complications of XEN on non-European ethnicities, especially on Asian, are in urgent need before XEN is widely applied.