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

Microenvironment-regulated dual-hydrophilic coatings for glaucoma valve surface engineering

Glaucoma valves (GVs) play an essential role in treating glaucoma. However, fibrosis after implantation has limited their long-term success in clinical applications. In this study, we aimed to develop a comprehensive surface-engineering strategy to improve the biocompatibility of GVs by constructing a microenvironment-regulated and dual-hydrophilic antifouling coating on a GV material (silicone rubber, SR). The coating was based on a superhydrophilic polydopamine (SPD) coating with good short-range superhydrophilicity and antifouling abilities. In addition, SPD coatings contain many phenolic hydroxyl groups that can effectively resist oxidative stress and the inflammatory microenvironment. Furthermore, based on its in situ photocatalytic free-radical polymerization properties, the SPD coating polymerized poly 2-methylacryloxyethylphosphocholine, providing an additional long-range hydrophilic and antifouling effect. The in vitro test results showed that the microenvironment-regulated and dual-hydrophilic coatings had anti-protein contamination, anti-oxidation, anti-inflammation, and anti-fiber proliferation capabilities. The in vivo test results indicated that this coating substantially reduced the fiber encapsulation formation of the SR material by inhibiting inflammation and fibrosis. This design strategy for dual hydrophilic coatings with microenvironmental regulation can provide a valuable reference for the surface engineering design of novel medical implantable devices. STATEMENT OF SIGNIFICANCE: Superhydrophilic polydopamine (SPD) coatings were prepared on silicone rubber (SR) by a two-electron oxidation method. Introduction of pMPC to SPD surface using photocatalytic radical polymerization to obtain a dual-hydrophilic coating. The dual-hydrophilic coating effectively modulates the oxidative and inflammatory microenvironment. This coating significantly reduced protein contamination and adhesion of inflammatory cells and fibroblasts in vitro. The coating-modified SR inhibits inflammatory and fibrosis responses in vivo, promising to serve the glaucoma valves.

A Retrospective Comparison of Ahmed Glaucoma Valve Implants with or without Ologen Collagen Matrix

Purpose

To study the effects of Ologen collagen matrix on the outcomes of the Ahmed glaucoma valve implant.

Study Design

Retrospective case-control multicenter study, conducted at four centers, comparing the 6-month outcomes of Ahmed valve implants with or without Ologen.

Participants

The study included 125 eyes in a 4:1 pairing (25 patients with Ologen matched to 100 patients without Ologen).

Intervention

Ologen was placed over the Ahmed plate in the study group. Success was defined as an intraocular pressure (IOP) ≤ 21 mmHg either with no medication (complete success) or regardless of medications (qualified success). Other outcomes included IOP variation, eye drop use, and surgical complications.

Results

Overall, the IOP decreased from 30.72 ± 9.08 to 16.14 ± 4.79 mmHg (p=0.0001). Of the 125 eyes, 26 achieved complete success and 94 achieved qualified success. There was no difference in complete success between the groups (p=0.12); however, there was a difference in qualified success (p=0.01), with better results in the no-Ologen group (80% vs 56%). There were no differences in the decrease in medications (p=0.06), as well as the incidence of complications (p=0.69). Although the need for postoperative surgical reintervention was higher in the no-Ologen group (13% vs 4%), the difference was not significant (p=0.2).

Conclusion

The reductions in IOP and number of medications were similar in both groups after 6 months, with similar complication rates. The qualified success rate was lower in the Ologen group, but further studies are needed to clarify the role of Ologen in Ahmed valve implants.

Comparison of surgical outcomes with and without Ologen collagen matrix augmentation during XEN gel stent implantation

Background

To compare the surgical outcomes and postoperative complications with and without Ologen collagen matrix augmentation during XEN gel stent implantation.

Methods

We retrospectively analyzed patients who underwent XEN gel stent implantation with an ab externo technique. The amount of intraocular pressure (IOP) reduction, percentage of postoperative complications and additional management, and surgical success defined as IOP reduction greater than 20% compared with the preoperative IOP measurement were compared between Ologen-augmented and non-augmented groups. Groups of patients who underwent XEN gel stent implantation alone and combined with phacoemulsification were analyzed separately.

Results

A total 103 eyes of 103 participants were included. Of those, 72 eyes underwent standalone XEN gel stent implantation: 42 eyes with Ologen augmentation (Oloxen group) and 30 eyes without Ologen augmentation (Xen group). Thirty-one eyes underwent XEN gel stent implantation with phacoemulsification: 19 eyes with Ologen augmentation (Phaco-Oloxen group) and 12 eyes without Ologen augmentation (PhacoXen group). The surgical success rate at six months postoperatively was not different between the Oloxen and Xen groups (56.4% vs 43.3%, P > 0.05) or between the Phaco-Oloxen group and PhacoXen group (57.9% vs 41.7%, P > 0.05). The prevalence of postoperative hypotony, 5-fluorouracil injections, use of anti-glaucoma medications, bleb needling, and additional glaucoma surgeries was not different between the Oloxen and Xen groups or between the Phaco-Oloxen and PhacoXen groups when assessed six months postoperatively.

Conclusions

All groups showed significant IOP reduction after XEN gel stent implantation, but there was no significant difference between the Ologen collagen matrix augmented and non-augmented groups in surgical outcomes.

Ologen augmentation of Ahmed valves in pediatric glaucomas

BACKGROUND

We previously showed that Ologen increased success and survival rates of Ahmed glaucoma devices in a small number of children. The current study analyzed the same surgical technique in an expanded cohort.

METHODS

Retrospective interventional case series of children who underwent Ologen augmentation of Ahmed glaucoma device (OAGD) from 2018 to 2021 with ≥6 months' postoperative follow-up. Complete success was defined as intraocular pressure (IOP) of 5-20 mm Hg without glaucoma medications or additional IOP-lowering surgeries. Complete or qualified success was defined as above, except that IOP control was maintained with or without glaucoma medications.

RESULTS

A total of 26 eyes of 18 patients underwent OAGD at a median age of 2.0 years. Diagnoses included primary congenital glaucoma (5 eyes) and glaucoma secondary to nonacquired ocular anomalies (9 eyes), nonacquired systemic anomalies (8 eyes), and acquired conditions (4 eyes). Seventeen eyes had ≥1 prior eye surgery (average, 1.6 ± 0.9 surgeries per eye). Preoperative IOP was 29.4 ± 9.9 mm Hg on an average of 2.7 ± 1.0 glaucoma medications. At final follow-up (1.3 ± 1.0 years; median 1.0), IOP (13.4 ± 4.7 mm Hg) and number of glaucoma medications (0.3 ± 0.7, median 0) were significantly decreased (P < 0.0001). Complete success was achieved in 77% of eyes (20/26); Kaplan Meier analysis showed 1- and 3-year survival rates of 82% (95% CI, 59-93) and 60% (95% CI, 25-83), respectively. Complete or qualified success was achieved in 100% of eyes (26/26) at final follow-up. There were no visually devastating complications.

CONCLUSIONS

OAGD showed a high rate of success defined by decreased IOP and medication dependency in our study cohort of pediatric glaucoma patients.

Long-term comparison of the outcomes of Ahmed Glaucoma Valve surgery between glaucoma surgeons and cornea trained surgeons

PURPOSE

To compare the long-term outcomes obtained by glaucoma surgeons versus cornea trained surgeons performing Ahmed glaucoma valve (AGV) surgery.

METHODS

Of the total 376 patients (3 month to 83 year) conducted in this retrospective study, 130 patients with refractory glaucoma were evaluated who had been followed up for at least six months during ten years period. The primary outcome measure was the surgical success of AGV surgery that was categorized in two groups: (A5 ≤ IOP ≤ 21 mmHg and at least 20% reduction in IOP without any glaucoma medications (complete success) and reduction by using one or more glaucoma medications (qualified success) (B) similar to previous criteria but the cutoff for higher IOP at 16 mmHg without vision loss and the need for medication or re-surgery.

RESULTS

Mean age of the patients was 32.99 ± 24.20 years in the glaucoma surgeon group and 25.18 ± 24.33 years in the cornea trained surgeons group (P = 0.07). The overall success of both methods at the end of four years were 66.7% and 41.7% for the group of glaucoma surgeons and cornea trained surgeons, respectively (p = 0.661). The cumulative success according to criterion A and B was 66.7% in the glaucoma surgeon group and 47.1% in the others surgeon group (P = 0.661). Repeated glaucoma surgery was required in 33.3% and 52.9% of the patients in the glaucoma surgeon and cornea trained surgeons groups, respectively (P = 0.661). Although there was a significant difference for IOP among various follow-up periods (p = 0.004), this difference was not significant between the two groups (p = 0.374).Visual Acuity did not have a signifiant difference between various follow-up periods and surgeons groups (p = 0.419 and P = 0. 690, respectively).

CONCLUSION

There were comparable outcomes with regard to complications and success rates between glaucoma surgeons and cornea trained surgeons performing AGV surgery.

Intraluminal stenting versus external ligation of Ahmed glaucoma valve in prevention of postoperative hypotony

AIM

To compare intraluminal stenting and external ligation of Ahmed glaucoma valves (AGV) for refractory glaucoma management and postoperative hypotony prevention.

METHODS

This randomized prospective blind study included 30 eyes of 25 patients (age range: 44-56y) with refractory glaucoma. This study was conducted from September 2018 to January 2020. The study included two groups, AGV with intraluminal stenting group (n=15 eyes) and AGV with external ligation group (n=15 eyes). Follow-up period was one year postoperatively. The primary outcome was intraocular pressure (IOP) and its association with the number of postoperative glaucoma medications. IOP≤21 mm Hg without medications indicated complete success while IOP≤21 mm Hg with medications indicated qualified success; and IOP<6 mm Hg was defined as hypotony.

RESULTS

After a year of follow-up, IOP was significantly reduced in the intraluminal stenting group than in the external ligation group (11.67±0.89 vs 14.2±4.0 mm Hg, respectively, P=0.024). Postoperative hypotony was more common in the external ligation group (2 cases, 13.33%) than in the intraluminal stenting group (1 case, 6.67%).

CONCLUSION

Application of intraluminal stenting or external ligation during AGV surgery usually prevents postoperative hypotony (transient and persistent) that occurs in conventional AGV surgery.

Utility of Collagen Matrix Insertion during Ahmed Valve Implantation with Adjunctive Mitomycin-C: Outcomes at One-year

Purpose: To compare the surgical outcomes of adjunctive mitomycin-C (MMC) Ahmed valve implantation with and without collagen matrix insertion.Methods: We retrospectively reviewed 108 eyes of 108 patients who underwent Ahmed valve implant surgery with adjunctive MMC. Collagen matrix insertion/Ahmed valve implant surgery (CM-AGV) was performed on 55 eyes, while conventional Ahmed valve implant surgery (AGV) was performed on 53 eyes. We defined surgical failure as an intraocular pressure (IOP) > 18 mmHg or <5 mmHg on two or more consecutive visits, regardless of medication status.Results: After surgery, the IOP and number of topical medications required fell significantly (compared with the preoperative period) in both groups (both p < 0.001); these findings did not significantly differ between groups. The cumulative surgical success rates at 1 year did not significantly differ between groups (78.2% vs. 79.2%, p = 0.54). The only risk factor significantly associated with surgical failure was a postoperative hypertensive phase. Anterior chamber (compared with sulcus) tube placement was significantly associated with visual acuity loss at 1 year postoperatively, but this did not significantly differ between groups.Conclusions: At the 1-year follow-up after Ahmed implant surgery with adjunctive MMC, the success rates of surgery with and without collagen matrix insertion were similar.

Efficacy of biodegradable collagen matrix (Ologen® CM) in augmenting the success rate of Ahmed glaucoma valve implantation in canine glaucoma

OBJECTIVE

To prospectively assess the efficacy of a biodegradable collagen matrix (ologen) in dogs with uncontrolled glaucoma receiving an Ahmed glaucoma valve (AGV) implant.

ANIMAL STUDIED

Five client-owned dogs with glaucoma (five eyes).

PROCEDURES

Five eyes treated for uncontrolled glaucoma underwent AGV implantation with ologen. Ologen was placed on the AGV plate and tube with a scleral flap. Complete ophthalmological examinations were performed preoperatively and at 1 and 3 days, 1 and 2 weeks, and 1, 2, 3, and 6 months postoperatively. Surgical outcomes were assessed based on the intraocular pressure (IOP), vision, frequency of anti-glaucoma eye drops, and bleb morphology; complications, if any, were recorded. The number of dogs with an IOP <20 mmHg with or without topical medications were tabulated and compared to those with an IOP ≥20 mmHg or those requiring surgery to maintain the IOP at <20 mmHg.

RESULTS

The IOP significantly decreased from 47.00 ± 5.09 mmHg preoperatively to 17.00 ± 0.71 mmHg 6 months postoperatively (p = .008). IOP was controlled (<20 mmHg) in 5/5 dogs at 6 months postoperatively. Brief periods of elevated IOP (IOP ≥ 20 mmHg, IOP spike) occurred in one eye (case 5) at 1 month (35 mmHg) and 2 months (33 mmHg) postoperatively. The anti-glaucoma eye drop frequency decreased from 3.2 ± 0.44 preoperatively to 1.6 ± 0.90 at 6 months postoperatively (p = .007).

CONCLUSIONS

To our knowledge, this is the first study to assess the potential safety of AGV implantation with ologen for canine glaucoma. This method effectively controlled the IOP, without any adverse effects.

Ologen augmentation of Ahmed glaucoma drainage devices in pediatric glaucomas

Background

Limited data exists on the effectiveness of the collagen matrix, Ologen, on increasing Ahmed glaucoma valve (AGV) success in childhood glaucomas.

Methods

Ocular examination and surgical details of pediatric patients who underwent AGV placement ± Ologen augmentation between 2012 and 2020. Complete success was defined as intraocular pressure (IOP) between 5 and 20 mmHg without glaucoma medications and additional IOP-lowering surgeries. Qualified success was defined as above, except IOP control maintained with or without glaucoma medications.

Results

Twenty-two eyes of 16 patients underwent AGV placement of which 6 eyes had Ologen-augmentation (OAGV) and 16 eyes had conventional surgery (CAGV). Average age was 6.4 ± 5.1 years with 4.2 ± 2.5 follow-up years. There was no difference in age, number of previous surgeries, and preoperative IOP and glaucoma medications. At final follow-up, success rate was 100% (5 eyes complete, 6 eyes qualified) in the OAGV group compared to 31% (0 eyes complete, 5 eyes qualified) in the CAGV group. One and two-year survival rates were 100% for OAGV compared to 62 and 38% for CAGV. Postoperative IOP was significantly lower at 1-month and final follow-up (p = 0.02) as was the number of glaucoma medications at 3, 6, 12-months and final follow-up (p < 0.05) in the OAGV group.

Conclusions

Ologen-augmentation increased the success and survival rates of AGVs in childhood glaucomas. Further, Ologen mitigated the hypertensive phase and decreased medication dependency. Longer follow-up with a greater number of eyes is required to fully evaluate the effectiveness of OAGV.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12886-021-01827-4.

A Prospective Randomized Trial of Ahmed Glaucoma Drainage Device Implantation with or without Ologen Collagen Matrix

PURPOSE

The purpose of this study is to evaluate the effectiveness of Ologen collagen matrix (OCM; Aeon Astron Corporation) in the prevention of the postoperative hypertensive phase and on long-term intraocular pressure (IOP) control after Ahmed glaucoma valve (AGV; New World Medical) implantation.

DESIGN

This is a prospective, randomized, controlled study of 26 patients treated at a tertiary care center, with 13 eyes assigned to each treatment arm.

PARTICIPANTS

Consecutive patients with refractory glaucoma requiring AGV implantation were enrolled. Refractory glaucoma was defined as IOP >21 mmHg on maximum tolerated glaucoma medications or progressive visual field and optic nerve head changes despite maximal tolerated medical therapy.

METHODS

In Ologen eyes, a round 12 × 1-mm OCM segment was placed flush over the AGV-FP7 plate immediately before conjunctival closure. Control eyes received conventional AGV surgery without OCM implantation.

MAIN OUTCOME MEASURES

The primary outcomes were postoperative IOP and requirement of pressure-lowering medications. On the basis of these measures, the rates of complete and qualified success over the course of follow-up were calculated. Complete success was defined as IOP ≤21 mmHg without antihypertensive medications. Qualified success was defined as IOP ≤21 mmHg with or without medications. Frequency of hypertensive phase was also determined.

RESULTS

Patients receiving Ologen-augmented AGV surgery exhibited significantly lower IOPs compared with control subjects at the 1-, 2-, and 3-month time points (P < 0.04). Maximum mean IOP postoperatively was 25.2 ± 7.4 for control eyes and 16.8 ± 8.9 for Ologen eyes, peaking at month 2 for both groups and stabilizing by month 6. No differences in average number of pressure-lowering medications were detected between groups. There were no statistically significant differences in complete or qualified success rates at 6 and 12 months. The frequency of hypertensive phase was 61.5% in control eyes and 38.5% in OCM-implanted eyes.

CONCLUSIONS

Ologen collagen matrix-augmented AGV surgery may provide better IOP control in the intermediate postoperative period and blunt the hypertensive phase compared with AGV implantation alone.

Subconjunctival Injections of Mitomycin C Are Associated with a Lower Incidence of Hypertensive Phase in Eyes with Ahmed Glaucoma Valve

PURPOSE

To evaluate the association of intraoperative and postoperative subconjunctival injections of mitomycin C (MMC) and rate of the hypertensive phase after implantation of the Ahmed glaucoma valve (AGV).

DESIGN

Comparative case series.

PARTICIPANTS

This retrospective comparative study included 37 eyes of 35 patients with uncontrolled glaucoma on maximum tolerated medical therapy who underwent implantation of AGV by a single surgeon.

METHODS

Consecutive cases operated without the use of MMC from 2015 to 2017 were compared with consecutive cases operated from 2018 to 2019 under a standardized protocol of subconjunctival MMC injections. The MMC group received 0.1 ml of MMC (0.25 mg/ml) injected intraoperatively, at 1 and 4 weeks after the surgery.

MAIN OUTCOME MEASURES

Incidence of the hypertensive phase (defined as intraocular pressure [IOP] >21 mmHg during the first 3 postoperative months) was compared across groups. Intraocular pressure and glaucoma medications were also compared during the course of the first 6 postoperative months.

RESULTS

In the MMC and no-MMC groups, 17.6% (3/17) and 55.0% (11/20) of the cases exhibited a hypertensive phase (P = 0.04), respectively. Both groups were comparable in baseline characteristics, including age, preoperative IOP, preoperative glaucoma medications, and previous glaucoma surgeries. At 6 months, mean IOP was 14.0 ± 0.8 mmHg and 14.7 ± 0.9 mmHg for the MMC and no-MMC groups, respectively (P = 0.6). The mean number of glaucoma medications at 6 months was 1.2 ± 0.2 and 2.2 ± 0.3 in the MMC and no-MMC groups, respectively (P = 0.007).

CONCLUSIONS

Eyes that underwent implantation of AGV experienced a lower incidence of hypertensive phase and required fewer medications when using a standardized protocol of intraoperative and postoperative subconjunctival MMC injections.

Surgical outcomes of Glaucoma associated with Axenfeld-Rieger syndrome

Background

The surgical management of glaucoma associated with Axenfeld-Rieger Syndrome (ARS) is poorly described in the literature. The goal of this study is to compare the effectiveness of various glaucoma surgeries on intraocular pressure (IOP) management in ARS.

Methods

Retrospective cohort study at a university hospital-based practice of patients diagnosed with ARS between 1973 and 2018. Exclusion criterion was follow-up less than 1 year. The number of eyes with glaucoma (IOP ≥ 21 mmHg with corneal edema, Haabs striae, optic nerve cupping or buphthalmos) requiring surgery was determined. The success and survival rates of goniotomy, trabeculotomy±trabeculectomy (no antifibrotics), cycloablation, trabeculectomy with anti-fibrotics, and glaucoma drainage device placement were assessed. Success was defined as IOP of 5-20 mmHg and no additional IOP-lowering surgery or visually devastating complications. Kaplan-Meier survival curves and the Wilcoxon test were used for statistical analysis.

Results

In 32 patients identified with ARS (median age at presentation 6.9 years, 0–58.7 years; median follow-up 5.4 years, 1.1–43.7 years), 23 (71.9%) patients were diagnosed with glaucoma at median age 6.3 years (0–57.9 years). In glaucomatous eyes (46 eyes), mean IOP at presentation was 21.8 ± 9.3 mmHg (median 20 mmHg, 4-45 mmHg) on 1.0 ± 1.6 glaucoma medications. Thirty-one eyes of 18 patients required glaucoma surgery with 2.2 ± 1.2 IOP-lowering surgeries per eye. Goniotomy (6 eyes) showed 43% success with 4.3 ± 3.9 years of IOP control. Trabeculotomy±trabeculectomy (6 eyes) had 17% success rate with 14.8 ± 12.7 years of IOP control. Trabeculectomy with anti-fibrotics (14 eyes) showed 57% success with 16.5 ± 13.5 years of IOP control. Ahmed© (FP7 or FP8) valve placement (8 eyes) had 25% success rate with 1.7 ± 1.9 years of IOP control. Baerveldt© (250 or 350) device placement (8 eyes) showed 70% success with 1.9 ± 2.3 years of IOP control. Cycloablation (4 eyes) had 33% success rate with 2.7 ± 3.5 years of IOP control. At final follow-up, mean IOP (12.6 ± 3.8 mmHg, median 11.8 mmHg, 7-19 mmHg) in glaucomatous eyes was significantly decreased (p < 0.0001), but there was no difference in number of glaucoma medications (1.6 ± 1.5, p = 0.1).

Conclusions

In our series, greater than 70% of patients with ARS have secondary glaucoma that often requires multiple surgeries. Trabeculectomy with anti-fibrotics and Baerveldt glaucoma drainage devices showed the greatest success in obtaining IOP control.

Use of a Collagen Matrix Implant as an Adjuvant in Combined Surgery Involving Phacoemulsification and Nonpenetrating Deep Sclerectomy

AIM

To assess the efficacy and safety of the Ologen collagen matrix as an adjuvant for combined phacoemulsification and nonpenetrating deep sclerectomy (Phaco-NPDS), in addition to mitomycin C (MMC).

MATERIALS AND METHODS

This was a longitudinal retrospective comparative study of eyes treated with Phaco-NPDS, with (group 1) or without (group 2) an Ologen collagen matrix implant, in addition to MMC. The main outcome measures were operative success [absolute success: intraocular pressure (IOP) <18 mm Hg and an at least 20% reduction from baseline without medication; relative success: IOP<18 mm Hg and at least 20% reduction from baseline IOP with or without medication], mean reductions (%) in IOP and medication use; number of postoperative reinterventions (goniopuncture, needling, reoperation), and number of complications.

RESULTS

The mean age of the study population (N=100) was 72.0±9.7 years. Groups 1 (n=51) and 2 (n=49) achieved absolute success rates of 72.5% and 55.1%, respectively (P=0.054), and relative success rates of 90.2% and 83.7%, respectively (P=0.251). From a similar baseline IOP (19.8 and 20.7 mm Hg in groups 1 and 2, respectively, P=0.527), eyes in group 1 achieved a significant lower 12-month IOP (11.7 vs. 14.5 mm Hg, respectively, P=0.002) and a lower rate of medication use (0.2 vs. 0.9, respectively, P<0.001). Eyes in group 2 presented with a higher rate of bleb failure (12.2% vs. 2.0%, P=0.028), leading to a higher rate of needling procedures (38.8% vs. 2.0%, P<0.001) during the postoperative period.

CONCLUSIONS

The adjunctive use of Ologen collagen matrix in addition to MMC during Phaco-NPDS was associated with a higher rate of absolute success, a lower mean IOP at 12 months, a lower rate of bleb failure, and a lower rate of postoperative bleb needling.