Subconjunctival microinvasive glaucoma surgeries: an update on the Xen gel stent and the PreserFlo MicroShunt

Structural reversal of disc cupping measured in Bruch's membrane opening-based OCT morphometry after PRESERFLO microshunt implantation for open-angle glaucoma

BACKGROUND/ AIMS

To analyze the longitudinal change in Bruch's membrane opening minimal rim width (BMO-MRW) and peripapillary retinal nerve fiber layer (pRNFL) thickness using optical coherence tomography (OCT) after implantation of a PRESERFLO® microshunt for surgical glaucoma management in adult glaucoma patients.

METHODS

Retrospective data analysis of 59 eyes of 59 participants undergoing implantation of a PRESERFLO microshunt between 2019 and 2022 at a tertiary center for glaucoma management. Surgical management included primary temporary occlusion of the glaucoma shunt to prevent early hypotony. Pre- and post-operative OCT examinations of the optic nerve head (ONH) and intraocular pressure (IOP) were assessed. Longitudinal change in morphometric spectral domain OCT parameters of the ONH was correlated to change in IOP.

RESULTS

BMO-MRW increased significantly between baseline (BL) and follow-up (FU) within the first three months after surgery (BL = 171.15 ± 66.80 μm; FU = 180.78 ± 70.394 μm; p = 0.034). For the same postoperative period, the mean preoperative IOP of 24.97 ± 7.22mmHg was lowered after surgery to 13.70 ± 5.09 mmHg. Eighteen months after surgery, there was no significant change in BMO-MRW compared to baseline (BL = 169.83 ± 52.69 μm; FU = 164.98 ± 55.85 μm; p = 0.271), while mean IOP was 13.08 ± 4.48 mmHg. A decrease in IOP correlated significantly with a change in BMO-MRW (r = 0.453, p < 0.05) three months after surgery. Peripapillary RNFL thickness was unchanged in follow-up after three months (p > 0.16) and significantly decreased in later follow-up (p = 0.009).

CONCLUSION

PRESERFLO® microshunt implantation with primary temporary occlusion leads to a significant transient increase in BMO-MRW. This phenomenon is also known as structural reversal of disc cupping (SRDC). The effect seems to be less pronounced and of shorter duration when compared to previous data after trabeculectomy with comparable pre- and postoperative IOP levels.

Cataract surgery combined with glaucoma surgery

PURPOSE OF REVIEW

This review evaluates the surgical management of glaucoma in patients undergoing cataract surgery. Combining both procedures present challenges in balancing intraocular pressure (IOP) control, minimizing postoperative complications, and achieving optimal refractive outcomes.

RECENT FINDINGS

Recent studies highlight the effectiveness of combined glaucoma and cataract surgeries, with traditional filtering surgeries and MIGS showing significant IOP reduction. The abundance of long-term studies shows that MIGS can offer an effective and safer alternative when carefully tailored to meet the specific needs of each patient.

SUMMARY

Combining glaucoma and cataract surgery is a promising approach for patients with coexisting conditions. While traditional surgeries offer robust IOP reduction, MIGS procedures offer better safety profiles with fewer complications and more predictable refractive results. Surgeons must carefully consider the timing and choice of procedures, with further research required to develop standardized treatment algorithms.

Inhibition of the rapamycin-insensitive mTORC1 /4E-BP1 axis attenuates TGF-β1-induced fibrotic response in human Tenon's fibroblasts

Subconjunctival fibrosis is the major cause of failure in both conventional and modern minimally invasive glaucoma surgeries (MIGSs) with subconjunctival filtration. The search for safe and effective anti-fibrotic agents is critical for improving long-term surgical outcomes. In this study, we investigated the effect of inhibiting the rapamycin-insensitive mTORC1/4E-BP1 axis on the transforming growth factor-beta 1(TGF-β1)-induced fibrotic responses in human Tenon's fibroblasts (HTFs), as well as in a rat model of glaucoma filtration surgery (GFS). Primary cultured HTFs were treated with 3 ng/mL TGF-β1 for 24 h, followed by treatment with 10 μM CZ415 for additional 24 h. Rapamycin (10 μM) was utilized as a control for mTORC1/4E-BP1 signaling insensitivity. The expression levels of fibrosis-associated molecules were measured using quantitative real-time PCR, Western blotting, and immunofluorescence analysis. Cell migration was assessed through the scratch wound assay. Additionally, a rat model of GFS was employed to evaluate the anti-fibrotic effect of CZ415 in vivo. Our findings indicated that both rapamycin and CZ415 treatment significantly reduced the TGF-β1-induced cell proliferation, migration, and the expression of pro-fibrotic factors in HTFs. CZ415 also more effectively inhibited TGF-β1-mediated collagen synthesis in HTFs compared to rapamycin. Activation of mTORC1/4E-BP signaling following TGF-β1 exposure was highly suppressed by CZ415 but was only modestly inhibited by rapamycin. Furthermore, CZ415 was found to decrease subconjunctival collagen deposition in rats post GFS. Our results suggest that rapamycin-insensitive mTORC1/4E-BP1 signaling plays a critical role in TGF-β1-driven collagen synthesis in HTFs. This study demonstrated that inhibition of the mTORC1/4E-BP1 axis offers superior anti-fibrotic efficacy compared to rapamycin and represents a promising target for improving the success rate of both traditional and modern GFSs.

Wound Modulations in Glaucoma Surgery: A Systematic Review

Excessive fibrosis and resultant poor control of intraocular pressure (IOP) reduce the efficacy of glaucoma surgeries. Historically, corticosteroids and anti-fibrotic agents, such as mitomycin C (MMC) and 5-fluorouracil (5-FU), have been used to mitigate post-surgical fibrosis, but these have unpredictable outcomes. Therefore, there is a need to develop novel treatments which provide increased effectiveness and specificity. This review aims to provide insight into the pathophysiology behind wound healing in glaucoma surgery, as well as the current and promising future wound healing agents that are less toxic and may provide better IOP control.

Trabecular Procedures Combined with Cataract Surgery for Open-Angle Glaucoma: A Report by the American Academy of Ophthalmology

PURPOSE

To determine the intraocular pressure (IOP) reduction of various trabecular procedures (a form of minimally invasive glaucoma surgery [MIGS]) combined with cataract surgery compared with cataract surgery alone, to compare the safety of the various trabecular procedures, and to highlight patient characteristics that may favor one trabecular procedure over another.

METHODS

A search of English-language peer-reviewed literature in the PubMed database was initially conducted in February 2021 and updated in April 2023. This yielded 279 articles. Twenty studies met initial inclusion and exclusion criteria and were assessed for quality by the panel methodologist. Of these, 10 were rated level I, 3 were rated level II, and 7 were rated level III. Only the 10 level I randomized controlled trials (RCTs) were included in this assessment, and all were subject to potential industry-sponsorship bias.

RESULTS

The current analysis focuses on the amount of IOP reduction (in studies that involved medication washout) and on IOP reduction with concurrent medication reduction (in studies that did not involve medication washout). Based on studies that performed a medication washout, adding a trabecular procedure to cataract surgery provided an additional 1.6 to 2.3 mmHg IOP reduction in subjects with hypertensive, mild to moderate open-angle glaucoma (OAG) at 2 years over cataract surgery alone, which itself provided approximately 5.4 to 7.6 mmHg IOP reduction. In other words, adding a trabecular procedure provided an additional 3.8% to 8.9% IOP reduction over cataract surgery alone, which itself provided 21% to 28% IOP reduction. There was no clear benefit of one trabecular procedure over another. Patient-specific considerations that can guide procedure selection include uveitis predisposition, bleeding risk, metal allergy, and narrowing of Schlemm's canal. There are no level I data on the efficacy of trabecular procedures in subjects with pretreatment IOP of 21 mmHg or less.

CONCLUSIONS

Trabecular procedures combined with cataract surgery provide an additional mild IOP reduction over cataract surgery alone in hypertensive OAG subjects. Additional research should standardize outcome definitions, avoid industry sponsorship bias, and study the efficacy of these procedures in normotensive OAG.

FINANCIAL DISCLOSURE(S)

Proprietary or commercial disclosure may be found in the Footnotes and Disclosures at the end of this article.

Ab Externo SIBS Microshunt with Mitomycin C for Open-Angle Glaucoma: Three-Year Results as a Primary Surgical Intervention

PURPOSE

To determine the effectiveness, risk factors for surgical failure, and adverse events in a large cohort of patients receiving stand-alone ab externo poly(styrene-block-isobutylene-block-styrene) (SIBS) microshunt implantation with mitomycin C (MMC) over 3 years of follow-up.

DESIGN

Retrospective, interventional case series.

PARTICIPANTS

Glaucomatous eyes on maximally tolerated medical therapy with no previous subconjunctival glaucoma surgery.

METHODS

Records of eyes that underwent ab externo SIBS microshunt with MMC between July 2015 and November 2017 were reviewed. Data from all follow-up visits were utilized and included intraocular pressure (IOP), medication use, postoperative interventions, complications, and reoperations.

MAIN OUTCOME MEASURES

The primary outcome was proportion of eyes at 3 years with (1) no 2 consecutive IOPs > 17 mmHg (or < 6 mmHg with > 2 lines of vision loss from baseline); (2) ≥ 20% reduction from baseline IOP; and (3) using no glaucoma medications (complete success). Secondary outcomes included 14 and 21 mmHg upper IOP thresholds with and without ≥ 20% IOP reduction from baseline, qualified success (with glaucoma medications), risk factors for failure, median IOP/medications, postoperative interventions, complications, and reoperations.

RESULTS

One hundred fifty-two eyes from 135 patients were included. Complete and qualified success was achieved in 55.6% and 74.8% of eyes, respectively. Time to first glaucoma medication use was a median of 16.9 (interquartile range [IQR], 12.1-34.1) months; however, 59.4% of eyes remained medication free at 3 years. Significant risk factors for failure included receiving < 0.4 mg/ml of MMC (adjusted hazard ratio [HR], 2.42; 95% confidence interval [CI], 1.44-4.05) and baseline IOP < 21 mmHg (adjusted HR, 1.79; 95% CI, 1.03-3.13). The most common complications were choroidal detachment, hyphema, and anterior chamber shallowing, occurring in 7%, 5%, and 5% of eyes, respectively. The needling rate was 15.1%, with significantly higher frequency for baseline IOP > 21 mmHg (HR, 3.21; 95% CI, 1.38-7.48). Revisions occurred in 7% of eyes and reoperations in 2.6%. Eyes receiving < 0.4 mg/ml of MMC underwent more revisions (odds ratio, 4.9; 95% CI, 1.3-18.3).

CONCLUSIONS

Three-year follow-up data from this large cohort continues to support promising rates of qualified and complete success, with decreased medication burden postoperatively and few postoperative complications and interventions. Comparisons to other filtering surgeries will further facilitate integration of the SIBS microshunt into the surgical treatment paradigm.

FINANCIAL DISCLOSURE(S)

Proprietary or commercial disclosure may be found in the Footnotes and Disclosures at the end of this article.

Preserflo microshunt implant for the treatment of refractory uveitic glaucoma: 36-month outcomes

OBJECTIVES

To determine 36-month efficacy and safety outcomes of the PRESERFLO Microshunt implant in the treatment of refractory uveitic glaucoma.

METHODS

Consecutive patients with uncontrolled uveitic glaucoma despite maximum medical treatment received PRESERFLO Microshunt implant with mitomycin C (MMC) in a tertiary referral glaucoma practice. Efficacy and safety outcomes data were collected at month 6, 12, 24, and 36, postoperatively. The primary outcome was surgical success, defined as intraocular pressure (IOP) between 5 and 21 mmHg or > 20% reduction from baseline, and absence of criteria for surgical failure. Secondary outcomes were IOP, visual acuity (VA), use of glaucoma medical therapy, surgical complications, rate of reoperation for glaucoma.

RESULTS

21 eyes of 21 patients were included. The mean rate of success was 0.74 (95%CI 0.48-0.88), 0.68 (0.43-0.84), 0.47 (0.25-0.67), and 0.47 (0.25-0.67, at 6, 12, 24, and 36 months postoperatively, respectively. The mean IOP decreased by 30.7% (95% CI 13.7-47.7), 26.5% (95% CI 3.2-49.8), 33.5% (95% CI 21.8-45.3), and 30.1% (95% CI 7.2-52.9) from baseline at postoperative month 6, 12, 24, and 36, respectively (p < 0.001). The mean ± SD number of glaucoma medications decreased from 4.1 ± 0.9 to 0.9 ± 1.2 at the final follow up (p = 0.0005). No sight-threatening complications were reported by 36 months.

CONCLUSIONS

Three-year results of the PRESERFLO Microshunt implant demonstrated favourable efficacy and safety profile in the treatment of refractory uveitic glaucoma.

Gelatin implant in the treatment of open-angle glaucoma: Safety and efficacy in real-life conditions

OBJECTIVE

To evaluate the safety and efficacy of the Xen® implant for the treatment of open-angle glaucoma.

MATERIAL AND METHOD

Retrospective study including patients who received the Xen® implant between January 2019 and December 2020 in a university hospital. Demographic and medical data were collected using DxCare® software. The primary endpoint was a 20% reduction in intraocular pressure (IOP) at 12 months according to Société Française du Glaucome (SFG) recommendations. The secondary endpoints were decrease in glaucoma medications and incidence of adverse events.

RESULTS

Fifty-three patients (65 eyes) were included (sex ratio 0.65, age 75.38±7.31 years). IOP decreased by 18.51% from 17.86±4.22mmHg to 14.55±2.66mmHg (P<0.05). The number of glaucoma medications was 2.16±1.01 preoperatively vs 0.49±0.94 postoperatively (P<0.05). Adverse events included 8 malpositionings, 3 of which required reoperation, 1 case of increased IOP resolved by trabeculectomy, 1 case of venous ischemia treated by photocoagulation, 3 choroidal detachments and 3 corneal ulcers. Needling was required for 18 eyes.

CONCLUSION

At 12 months, the IOP was lower than previously reported in the literature (14.55 vs 15.90mmHg, P<0.05), probably due to a lower preoperative IOP. The number of postoperative medications was similar to the literature (0.49 vs 0.40, P=0.51), as was the frequency of needling (27.69% vs 32.00%, P=0.36). The frequency of malpositioning was higher (12.31% vs 7.70%, P<0.05), probably due to the management of complicated patients. The efficacy of Xen® was in line with recommendations. It would be interesting to compare the efficacy of Xen® with trabeculectomy.

Success rate in micropulse diode laser treatment with regard to lens status, refractive errors, and glaucoma subtypes

PURPOSE

To evaluate the efficacy of micropulse transscleral cyclophotocoagulation (MP-TSCPC) considering different characteristics: glaucoma subtypes and lens status.

METHODS

A retrospective case-series study was designed to evaluate intraocular pressure (IOP), and the number of IOP-lowering medications, used by glaucoma patients treated with MP-TSCPC between 2016 and 2019. Cases had a follow-up period of 12 months. Achieving an IOP reduction higher than 20%, or the decrease of at least one IOP-lowering medication, was considered a successful outcome. The same population was analyzed by classifying them in two groups as: glaucoma subtypes and lens status. The baseline spherical equivalent (SE) was also calculated for considering association with the achieved IOP.

RESULTS

A total of 86 eyes were included. In most cases, IOP and IOP-lowering medications were decreased with a statistically significant difference (p < 0.0001), and all of them had a successful outcome. The percentage of IOP drop oscillated between 25.9% (open-angle glaucoma sub-group) and 37.5% (pseudoexfoliative glaucoma sub-group), 12 months after surgery. The difference between the groups was not statistically significant (p 0.20 and 0.32 for glaucoma subtypes and lens status, respectively). The Pearson's coefficient obtained was low for the SE and IOP association, at the 12 -month postoperative mark (- 0.009; p < 0.001).

CONCLUSIONS

The MP-TSCPC treatment was successful in decreasing IOP and IOP-lowering medications, in different glaucoma subtypes. Differences between groups (glaucoma subtypes, phakic and pseudophakic eyes) were not statistically significant. No association was found between the SE and the IOP achieved value after MS-TSCPC treatment.

Budget impact analysis of the XEN®63 for the treatment of primary openangle glaucoma in Spain

BACKGROUND AND OBJECTIVE

To evaluate the economic impact in Spain derived from the introduction of the XEN®63 implant as a surgical alternative in the management of primary open angle glaucoma (POAG) with or without cataract in refractory patients.

MATERIALS AND METHODS

A budget impact analysis was designed to estimate the costs of surgical treatment of POAG from the perspective of the Spanish National Health System (NHS), over a time horizon of 1 year. The comparators considered (trabeculectomy, deep non-penetrating sclerectomy, Ahmed valve, iStent inject, Preserflo® microshunt and XEN®45) correspond to those used in Spanish public clinical practice. For the calculation of the target population, market shares and resource use in terms of follow-up visits, additional procedures and post-surgery complications, data from the literature were used and validated with a panel of 4 experts. Unit costs (€ 2021) were obtained from the ESALUD database.

RESULTS

The inclusion of XEN®63 could generate savings of €2,569,737 after one year since its introduction, derived from savings in the cost of the implant and procedure (-€423,120; -0.7%), follow-up visits (-€777,407; -4.5%), additional procedures (-€1,048,145; -20.6%) and post-surgery complications (-€321,065; -14.2%).

CONCLUSIONS

The incorporation of XEN63®in the surgical arsenal for the treatment of refractory POAG with and without cataracts could generate savings for the NHS.

Neovascular Glaucoma: An Update

Neovascular glaucoma (NVG) is a severe type of secondary glaucoma with devastating complications and generally poor visual prognosis. NVG is defined by the development of pathological neovessels over the iris and the iridocorneal angle that can block the outflow of aqueous humor, causing elevation of intraocular pressure (IOP). The pathogenesis of NVG is, in most cases, associated with ischemia of the posterior segment, which is most frequently associated with proliferative diabetic retinopathy or central retinal vein occlusion. The advanced stages of NVG are by iris and angle neovascularization, angle, and extremely high IOP, accompanied by ocular pain and poor vision. The therapeutic approach of NVG is based on the reduction of retinal ischemia by panretinal photocoagulation. Intravitreal anti-VEGF administration can contribute to the regression of neovascularization, and topical and systemic medications may be necessary for IOP control. However, if medical treatment with these agents is not enough, surgical procedures may be required to lower IOP and prevent glaucomatous optic neuropathy. Early and prompt diagnosis, with identification of the underlying etiology, can improve IOP control and final visual outcome. The aim of this study is to review current knowledge of the pathogenesis and management of NVG.

Evaluation of a Novel Αb Εxterno MicroShunt for the Treatment of Glaucoma

The surgical management of glaucoma has been revolutionized by the introduction of minimally invasive glaucoma surgery (MIGS). The various MIGS options aim to meaningfully lower intraocular pressure with a better safety profile than traditional glaucoma surgery. The key clinical attributes and the emerging potential of an ab externo MicroShunt (PreserFlo™) are reviewed in the context of published evidence and clinical experience. This novel MicroShunt consists of an 8.5-mm-long tube that is implanted in the eye via an ab externo approach enabling aqueous humor drainage into the sub-Tenon’s space through the formation of a bleb, similar in appearance to that created by trabeculectomy. The efficacy and safety of this procedure, the concomitant use of antimetabolites, the impact of tube positioning, and its future value in clinical practice are critically reviewed. Recent evidence has demonstrated the MicroShunt to be less effective than traditional filtration surgery, but with a significant improvement in safety. Cumulative data suggest that the new implant provides tangible clinical benefits to selected patients with glaucoma in need of further intraocular pressure (IOP) lowering. Future research should delineate the precise role of this and other MIGS options in the rapidly evolving glaucoma treatment algorithm.

Rational Design of Microfluidic Glaucoma Stent

Glaucoma is a common, irreparable eye disease associated with high intraocular pressure. One treatment option is implantation of a stent to lower the intraocular pressure. A systematic approach to develop a microchannel stent meshwork that drains aqueous humor from the anterior chamber of the eye into the subconjunctival space is presented. The stent has a large number of outlets within its mesh structure that open into the subconjunctiva. The development approach includes a flow resistance model of the stent. Local adaption of the stent’s tubular dimensions allows for adjustment of the flow resistance. In this way, an evenly distributed outflow into the subconjunctiva is achieved. We anticipate that microblebs will form at the stent outlets. Their size is crucial for drainage and control of intraocular pressure. An analytical model for bleb drainage is developed based on the porous properties of the subconjunctival tissue. Both models—the stent flow resistance model and the bleb drainage model—are verified by numerical simulation. The models and numerical simulation are used to predict intraocular pressure after surgery. They allow for a systematic and personalized design of microchannel stents. Stents designed in this way can stabilize the intraocular pressure between an upper and lower limit.

Optical coherence tomography-guided early postoperative management of XEN Gel implant

This interventional case series demonstrates the usefulness of anterior segment optical coherence tomography (AS-OCT) in guiding early postoperative management following XEN45 Gel Stent implantation, in conjunction with intraocular pressure (IOP) readings and slit lamp findings. Three primary open-angle glaucoma patients undergoing XEN45 Gel Stent implantation were included. Two patients received early postoperative needling because the IOP was not low enough and AS-OCT revealed that the XEN stent orifice was trapped by the Tenon's capsule. Immediately after needling, the distal tip of the XEN stent was freed and connected to a cystic space with significant IOP reduction. The third patient suffered from abrupt bleb flattening on the 5^th postoperative day following XEN stent implantation. AS-OCT revealed internal occlusion of the XEN stent with exudative material, which resolved spontaneously after intensifying topical steroids with improved bleb functioning 2 days later. AS-OCT provides in-depth microscopic evaluation of the XEN stent and its relationship with surrounding tissue. This information is helpful in identifying causes of impaired outflow, determining the timing, and effect of needling intervention in eyes with inadequate bleb functioning or IOP control, especially during the early postoperative period.

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.

Efficacy and Safety of PreserFlo® MicroShunt After a Failed Trabeculectomy in Eyes with Primary Open-Angle Glaucoma: A Retrospective Study

Introduction

To evaluate the efficacy and safety of PreserFlo^® MicroShunt in primary open angle glaucoma (POAG) eyes after a single failed trabeculectomy.

Methods

Retrospective review of POAG eyes with a failed trabeculectomy that underwent PreserFlo^® MicroShunt implantation from March 2019 to November 2019, in two Italian glaucoma centers. Pre- and postoperative data were collected and compared.

Results

A total of 31 surgeries in 31 patients were reviewed. Mean preoperative IOP and mean preoperative number of medications were 24.12 ± 3.14 mmHg and 3.29 ± 0.64, respectively, and decreased to 12.56 ± 2.64 mmHg and 0.46 ± 0.77 at the 12-month postoperative follow-up visit (p < 0.01). The most frequent adverse events were transient hypotony (6 eyes, 19.3%) and choroidal effusion (3 eyes, 9.6%). In all cases spontaneous resolution was observed, with no intervention.

Conclusion

In POAG eyes with a single failed trabeculectomy, the PreserFlo^® MicroShunt was safe and effective in reducing the IOP after a 12-month follow-up. The PreserFlo^® MicroShunt may represent a viable choice as a second surgery.

Effect of valproic acid on functional bleb morphology in a rabbit model of minimally invasive surgery

Purpose

To determine the effect of valproic acid (VPA) on bleb morphology and scar characteristics in a rabbit model of minimally invasive glaucoma surgery (MIGS).

Methods

Nine New Zealand white rabbits were subjected to MIGS with intraoperative implantation of the PreserFlo MicroShunt. Rabbits were then administered with subconjunctival injections of phosphate buffered saline (PBS) (n=4) or with VPA (n=5). Bleb morphology was examined by slit-lamp biomicroscopy and in vivo confocal microscopy. Postoperative day 28 tissues were examined by immunohistochemical evaluation and label-free multiphoton microscopy to visualise the collagen matrix, by terminal deoxynucleotidyl transferase dUTP nick-end labelling assay and immunofluorescent labelling for Ki67 expression to detect apoptosis and cell growth, and by real-time quantitative PCR to measure Col1a1, Fn, and Smad6 transcript expression.

Results

VPA-treated blebs were detectable on day 28, while the PBS-treated blebs were not detectable by day 14. VPA-treated blebs were diffuse, extended posteriorly with near normal conjunctival vascularity and featured a combination of reticular/blurred stromal pattern with evidence of relatively large stromal cysts. Instead of the deposition of thick, disorganised collagen fibres characteristic of the PBS bleb, the VPA bleb contained conspicuously thinner collagen fibres which were associated with similarly thinner fibronectin fibres. In corroboration, Col1a1 and Fn mRNA expression was reduced in the VPA blebs, while increased Smad6 expression implicated the disruption of the transforming growth factor beta pathway. Apoptosis and cell growth profiles appeared similar with both treatments.

Conclusions

The results support the application of VPA to enhance bleb morphology associated with good bleb function in MIGS with no apparent cytotoxicity.

[Results of filtering trabeculotomy (FTO) compared to conventional trabeculectomy (TE)-a matched case control study]

Ziel

Ziel dieser Studie war es, die 2‑Jahres-Ergebnisse der filtrierenden Trabekulotomie (FTO) im Vergleich zur konventionellen Trabekulektomie (TE) bei primärem Offenwinkelglaukom, Pseudoexfoliationsglaukom und Pigmentglaukom zu untersuchen.

Patienten und Methoden

Es wurden 30 konsekutive Patienten nach FTO und 87 Patienten nach TE nach intraokularem Druck (IOD) und Alter im Verhältnis 1:3 gematcht. Primärer Endpunkt war das Erreichen des Zieldrucks nach 2 Jahren. Als vollständiger Erfolg wurde ein IOD ohne Medikamente von ≤ 18 mm Hg bei gleichzeitiger IOD-Reduktion um ≥ 30 % definiert, als qualifizierter Erfolg, wenn hierfür zusätzlich Medikamente erforderlich waren. Sekundäre Endpunkte waren mittlere Drucksenkung, resultierende Sehschärfe, Komplikationen und nachfolgende Operationen. Die Operationstechnik der filtrierenden Trabekulotomie ist als Video zu diesem Beitrag abrufbar.

Ergebnisse

Zwei-Jahres-Daten konnten von 27 Patienten aus der FTO-Gruppe und 68 Patienten aus der TE-Gruppe erhoben werden. Die Patienten beider Gruppen wurden vor Beginn der Studie bezüglich Alter und IOD gematcht, waren aber auch bezüglich Sehschärfe, Geschlecht und Medikation nicht unterschiedlich. Der Median des präoperativen IOD unter Therapie betrug in beiden Gruppen 23,0 mm Hg. Nach den oben genannten Kriterien wurde ein qualifizierter 2‑Jahres-Erfolg bei 70,4 % der FTO-Gruppe und bei 77,6 % der TE-Gruppe erzielt (p = 0,60), ein vollständiger 2‑Jahres-Erfolg bei 33,3 % der FTO-Gruppe und bei 56,7 % der TE-Gruppe (p = 0,07). Beide Operationsmethoden senkten den Augeninnendruck nach 24 Monaten signifikant (p < 0,001), und zwar auf 12,8 mm Hg in der FTO-Gruppe und 11,0 mm Hg in der TE-Gruppe. Die Sehschärfe war postoperativ bei beiden Gruppen etwas verringert, unterschied sich jedoch nicht signifikant zwischen beiden Gruppen. Komplikations- und Reoperationsrate waren gering und unterschieden sich nicht zwischen den Gruppen.

Schlussfolgerung

FTO und TE sind nach 2 Jahren weitgehend gleichwertig bezüglich Zieldruck, IOD-Senkung, Sehschärfe und Komplikationen.

Video online

Die Online-Version dieses Beitrags (10.1007/s00347-021-01365-w) enthält ein Video zur Operationstechnik der filtrierenden Trabekulotomie. Beitrag und Video stehen Ihnen auf www.springermedizin.de zur Verfügung. Bitte geben Sie dort den Beitragstitel in die Suche ein, das Zusatzmaterial finden Sie beim Beitrag unter „Ergänzende Inhalte“.

[Glaucoma surgery today]

BACKGROUND

The main goals of glaucoma treatment are to preserve the visual function and maintain as high a quality of life as possible at a cost acceptable to society. Therefore, it is crucial to carefully observe each individual patient in order to determine an individual and personalized treatment approach.

MATERIAL AND METHODS

This article summarizes the advantages and disadvantages of medicinal glaucoma treatment as well as traditional methods of glaucoma surgery, based on the current state of knowledge. The article explains the various mechanisms of action of new minimally invasive procedures, introduces the methods mostly commonly used in Germany and gives recommendations for preoperative care and postoperative follow-up.

RESULTS/CONCLUSION

In addition to the plethora of medicinal glaucoma treatments and classical surgical procedures, new minimally invasive treatment alternatives have become available in the past few years. The latter are an option for an earlier surgical intervention, especially in naïve or previously treated patients who appear to be unsuitable for medicinal treatment.