Mid-term surgical success after transscleral ab interno glaucoma gel stent implantation.

PURPOSE: To investigate the surgical success and efficacy of XEN45 implantation (XEN45 µm, AbbVie Inc., USA) with and without combined cataract surgery up to the first 5 years. METHODS: In a prospective observational monocentric trial, 192 eyes of 157 patients with open-angle glaucoma received either XEN45 implants only (solo surgery group) or combined surgery/cataract surgeries (combined surgery group). Surgical success (qualified and full success; IOP-limit: ≤12, 15, 18, 21 mmHg), time to secondary IOP-lowering procedure, IOP and number of IOP-lowering medications were analysed for 1, 2, 3, 4 and 5 years. RESULTS: Compared to baseline, IOP (24.1 ± 8.1 to 12.6 ± 2.8 mmHg, -48%, p < 0.001) and the number of IOP-lowering medications (3.0 ± 1.0 to 1.5 ± 1.2, -50%, p < 0.001) decreased significantly at 5 years. Although no differences between IOP and the number of IOP-lowering medication courses between the groups were detected at 5 years (p > 0.11), the combined procedure (63%, 37%) showed better success rates compared to the solo procedure (36%, 13%) in the definition IOP ≤18 and ≤12 mmHg (p = 0.035, 0.028). Solo XEN45 procedures had a higher rate of secondary IOP-lowering procedures compared to combined XEN45 cataract procedures (hazard ratio: 2.02, 95%CI: 1.03-3.97, p = 0.04). Twenty per cent of the eyes, including both procedures, required a secondary IOP-lowering procedure within 5 years. CONCLUSIONS: The XEN45 implant is effective in lowering IOP and the number of IOP-lowering medications in patients with open-angle glaucoma in the mid-term. Comparing XEN45 implant results with the results of trabeculectomy available in current literature, we speculate that there might be a higher surgical success rate without medications in favour of trabeculectomy.

Distribution of the cysteinyl leukotriene system components in the human, rat and mouse eye.

The cysteinyl leukotrienes (CysLTs) have important functions in the regulation of inflammation and cellular stress. Blocking the CysLT receptors (CysLTRs) with specific antagonists is beneficial against progression of retinopathies (e.g. diabetic retinopathy, wet AMD). However, the exact cellular localization of the CysLTRs and their endogenous ligands in the eye have not been elucidated in detail yet. It is also not known whether the expression patterns differ between humans and animal models. Therefore, the present study aimed to describe and compare the distribution of two important enzymes in CysLT biosynthesis, 5-lipoxygenase (5-LOX) and 5-lipoxygenase-activating protein (FLAP), and of CysLTR1 and CysLTR2 in healthy human, rat and mouse eyes. Human donor eyes (n = 10) and eyes from adult Sprague Dawley rats (n = 5) and CD1 mice (n = 8) of both sexes were collected. The eyes were fixed in 4% paraformaldehyde and cross-sections were investigated by immunofluorescence with specific antibodies against 5-LOX, FLAP (human tissue only), CysLTR1 and CysLTR2. Flat-mounts of the human choroid were prepared and processed similarly. Expression patterns were assessed and semiquantitatively evaluated using a confocal fluorescence microscope (LSM710, Zeiss). We observed so far unreported expression sites for CysLT system components in various ocular tissues. Overall, we detected expression of 5-LOX, CysLTR1 and CysLTR2 in the human, rat and mouse cornea, conjunctiva, iris, lens, ciliary body, retina and choroid. Importantly, expression profiles of CysLTR1 and CysLTR2 were highly similar between human and rodent eyes. FLAP was expressed in all human ocular tissues except the lens. Largely weak immunoreactivity of FLAP and 5-LOX was observed in a few, yet unidentified, cells of diverse ocular tissues, indicating low levels of CysLT biosynthesis in healthy eyes. CysLTR1 was predominantly detected in ocular epithelial cells, supporting the involvement of CysLTR1 in stress and immune responses. CysLTR2 was predominantly expressed in neuronal structures, suggesting neuromodulatory roles of CysLTR2 in the eye and revealing disparate functions of CysLTRs in ocular tissues. Taken together, we provide a comprehensive protein expression atlas of CysLT system components in the human and rodent eye. While the current study is purely descriptive and therefore does not allow significant functional conclusions yet, it represents an important basis for future studies in diseased ocular tissues in which distribution patterns or expression levels of the CysLT system might be altered. Furthermore, this is the first comprehensive study to elucidate expression patterns of CysLT system components in human and animal models that will help to identify and understand functions of the system as well as mechanisms of action of potential CysLTR ligands in the eye.

Pericyte-derived cells participate in optic nerve scar formation.

Introduction: Pericytes (PCs) are specialized cells located abluminal of endothelial cells on capillaries, fulfilling numerous important functions. Their potential involvement in wound healing and scar formation is achieving increasing attention since years. Thus, many studies investigated the participation of PCs following brain and spinal cord (SC) injury, however, lacking in-depth analysis of lesioned optic nerve (ON) tissue. Further, due to the lack of a unique PC marker and uniform definition of PCs, contradicting results are published. Methods: In the present study the inducible PDGFRß-P2A-CreERT2-tdTomato lineage tracing reporter mouse was used to investigate the participation and trans-differentiation of endogenous PC-derived cells in an ON crush (ONC) injury model, analyzing five different post lesion time points up to 8 weeks post lesion. Results: PC-specific labeling of the reporter was evaluated and confirmed in the unlesioned ON of the reporter mouse. After ONC, we detected PC-derived tdTomato+ cells in the lesion, whereof the majority is not associated with vascular structures. The number of PC-derived tdTomato+ cells within the lesion increased over time, accounting for 60-90% of all PDGFRß+ cells in the lesion. The presence of PDGFRß+tdTomato- cells in the ON scar suggests the existence of fibrotic cell subpopulations of different origins. Discussion: Our results clearly demonstrate the presence of non-vascular associated tdTomato+ cells in the lesion core, indicating the participation of PC-derived cells in fibrotic scar formation following ONC. Thus, these PC-derived cells represent promising target cells for therapeutic treatment strategies to modulate fibrotic scar formation to improve axonal regeneration.

Radius-Maumenee syndrome: A case series with a long-term follow-up.

The aim of the case series is to highlight the surgical challenges experienced like failed intervention, choroidal effusion, a postoperative cystoid macular oedema, and describe treatment options for Radius-Maumenee syndrome. Authors reported on 3 bilateral cases of Radius-Maumenee syndrome which underwent medical treatment, trabeculectomy with Mitomycin C, implantation with XEN45, Ahmed glaucoma valve, Baerveldt glaucoma implant, and cyclophotocoagulation.

Five-year follow-up of corneal endothelial cell density after transscleral ab interno glaucoma gel stent implantation.

PURPOSE: This study investigates the course of the endothelial cell density over a period of 5 years after XEN45 implantation (XEN45µm, Allergan Plc., USA) with or without combined cataract surgery. METHODS: This is a prospective, cross-sectional, monocentric, non-randomized clinical trial with the intention to treat a population of the University Eye Clinic Glaucoma Service Salzburg. One hundred and fifty-five eyes with preoperative central corneal endothelial cell counts were subjected to XEN45 implantation with (combined surgery group) or without (solo surgery group) combined cataract surgery. Endothelial cell density was measured at 3 corneal positions. XEN45 location parameters were determined with anterior segment OCT and gonioscopy. RESULTS: In the combined surgery group, a significant reduction of central endothelial cell count was found at years 2 and 4 when compared to baseline (p = 0.001 and p = 0.02, n = 86), whereas at years 1, 3, and 5, no change was detected (all p > 0.09). The median reduction of endothelial cell count was - 79 (95% CI: - 183 to - 9) and - 93 (95% CI: - 220 to 23) cells at years 2 and 4, respectively. In the solo surgery group (n = 69), no significant change in endothelial cell counts was detected at any time during the 5-year evaluation period (all p > 0.07). Explorative data analyses revealed that XEN45 location parameters did not significantly influence the course of endothelial cell count over time. CONCLUSIONS: Endothelial cell loss after XEN45 implantation seems to be low. The present data suggest no impact on the position of the implant with regard to central endothelial cell counts in this study.

COVID-19 and the Rationale for Primary Selective Laser Trabeculoplasty and Diode Laser Transscleral Cyclophotocoagulation in Africa.

The recent COVID-19 pandemic has affected ophthalmologists' practices worldwide. Consequent global drug shortages and the limitations of medical glaucoma treatments in sub-Saharan Africa have highlighted the need for innovation in global ophthalmology to provide accessible, affordable, and effective glaucoma care. The role of lasers rather than medications for glaucoma patients in developing nations is emerging. Since lasers are easier to master than glaucoma surgery, it is pertinent to discuss the primary use of lasers in treating glaucoma in such nations. In particular, selective laser trabeculoplasty and diode laser transscleral cyclophotocoagulation seem to present a promising future for the treatment of glaucoma in Africa. In this report, we provide an evidence-based discussion exploring the emerging role of lasers in Africa.

Three-year effectiveness and safety of the XEN gel stent as a solo procedure or in combination with phacoemulsification in open-angle glaucoma: a multicentre study.

PURPOSE: To assess the 3-year effectiveness and safety of the XEN gel stent implanted ab interno in open-angle glaucoma (OAG). METHODS: This study was a multicentre, retrospective chart review of consecutive patients with OAG who underwent ab-interno gel stent placement alone or combined with phacoemulsification between 1 January 2014 and 1 October 2015. Outcome measures included mean changes in intraocular pressure (IOP) and IOP-lowering medication count from medicated baseline at 1, 2, 3 (primary outcome) and 4 years (if available) postimplantation. Intraoperative complications, adverse events of special interest (AESIs) and secondary surgical interventions (SSIs) were recorded. RESULTS: The safety and effectiveness populations included 212 eyes (primary and secondary) and 174 eyes (primary), respectively. Mean IOP and medication decreased from 20.7 mmHg and 2.5 at baseline (n = 163 primary/first implanted eyes) to 13.9 mmHg and 1.1 medications (n = 76) at 3 years postimplantation, respectively. Mean changes from baseline in IOP (-5.6, -6.2 and -6.6 mmHg) and IOP-lowering medication count (-1.8, -1.6 and -1.4) were statistically significant at 1, 2 and 3 years postimplantation, respectively. Results appeared comparable when implantation was performed with (n = 76) or without (n = 98) phacoemulsification. In primary eyes with 4-year IOP and medication count data (n = 27), mean IOP was 14.0 mmHg on 1.3 medications at 4 years postimplantation. Fifteen (7.1%) eyes had intraoperative complications, 31 (14.6%) experienced 46 postoperative AESIs, and 26 (12.3%) required SSI. CONCLUSION: The gel stent effectively lowered IOP and IOP-lowering medication count over 3 years, with a predictable and acceptable safety profile, when implanted via the traditional ab-interno technique.

Two-year efficacy after first transscleral controlled cyclophotocoagulation in patients with and without pseudoexfoliation.

PURPOSE: Transscleral controlled cyclophotocoagulation (COCO) is a transscleral 810-nm diode laser cyclophotocoagulation that automatically adjusts the applied laser energy utilizing an optical feedback loop. The present study investigates the influence of pseudoexfoliation (PEX) on the efficacy of COCO in a Caucasian study population. METHODS: Retrospective data from 130 consecutive eyes were analyzed during a 2-year follow-up. Baseline characteristics, intraocular pressure (IOP), number of IOP-lowering medications, visual field, best-corrected visual acuity (BCVA), and secondary surgical interventions (SSI) were analyzed. The primary endpoint was IOP reduction at M24 compared to baseline, and the secondary endpoints were IOP course, reduction of IOP-lowering medications, surgical success, and IOP-lowering SSIs stratified by PEX and baseline IOP. RESULTS: IOP reductions of -35, -39, -25, -25, -23, -34, and -36% could be achieved from baseline to D1, W1, M1, M3, M6, M12, and M24 (all p < 0.001), respectively, while there was a significant overall reduction over time (p < 0.001) in the number of topical IOP-lowering medications postoperatively. The proportion of eyes requiring additional systemic IOP-lowering medication reduced from 31 to 0% at M24 (p = 0.025). Eyes without PEX and IOP < 30 mmHg at baseline had the lowest risk for IOP-lowering SSIs (p < 0.03). BCVA dropped at M12 (0.25 [95% CI: 0.12-0.38]), and the drop persisted during the following 12 months. CONCLUSION: The present study demonstrates a midterm IOP-lowering effect after COCO while reducing the burden for topical and systemic IOP-lowering medications. Patients without PEX and IOP < 30 mmHg have a lower risk of SSI. The procedure per se cannot be excluded as causative for the decreased postoperative BCVA. Further prospective investigations are suggested.

Change in visual acuity 12 and 24 months after transscleral ab interno glaucoma gel stent implantation with adjunctive Mitomycin C.

PURPOSE: To analyze changes in best-corrected visual acuity (BCVA) after implantation of the transscleral ab interno glaucoma gel stent (XEN Gel Stent; Allergan, Dublin) in patients with open-angle glaucoma. METHODS: In a single-center, prospective, non-randomized study of 137 eyes with open-angle glaucoma which underwent implantation with XEN, 69 eyes underwent XEN implantation alone (group 1) and 68 eyes underwent XEN implantation and cataract surgery (group 2). BCVA (Bailey-Lovie chart, logMAR scale) was evaluated at baseline, postoperative day 1, weeks 1 and 2, and months 1, 3, 6, 12, and 24. Risk factors for decline in BCVA were analyzed in multivariate models. RESULTS: Baseline BCVA in group 1 was 0.21 ± 031; the group's mean BCVA did not change at any postoperative visit, although a ≥ 2-line loss of BCVA was detected in 15% (95% CI 7-29%) and 4% (95% CI 0-20%) after months 12 and 24, respectively. Baseline BCVA in group 2 was 0.33 ± 031; vision increased significantly at months 3 (0.22 ± 0.29, p = 0.015), 6 (0.20 ± 0.26, p = 0.006), 12 (0.18 ± 0.29, p = 0.001), and 24 (0.18 ± 0.29, p = 0.005). A ≥ 2-line loss of BCVA was reported in 4% (95% CI 1-15%) and 7% (95% CI 1-24%) after months 12 and 24, respectively. CONCLUSIONS: There was no deterioration of BCVA in group 1; those in group 2 had an overall significant increase in BCVA. BCVA decrease was lower than is typically reported in the literature post-trabeculectomy.

Immunohistochemical Characterization of Neurotransmitters in the Episcleral Circulation in Rats.

Purpose: Episcleral venous pressure (EVP) greatly influences steady-state IOP and recent evidence suggests a neuronal influence on EVP. Yet little is known about the innervation of the episcleral circulation and, more specifically, the neurotransmitters involved. We identify possible neurotransmitter candidates in the episcleral circulation of rats. Methods: Eight immersion-fixated rat eyes taken from four animals were cut into serial sections, followed by standard immunohistochemistry. Antibodies against choline acetyltransferase, dopamine-ß-hydroxylase, synaptophysine, PGP 9.5, VIP, neuronal nitric oxide synthase (nNOS), substance P, CGRP, and galanin were used. Additionally, colocalization experiments with smooth muscle actin and neurofilament (200 kDa) were performed. Results: In all specimens, the episcleral vessels showed immunoreactivity for smooth muscle actin and were reached by neurofilament (200 kDa)-positive structures. Furthermore, these structures colocalized with immunoreactivity for PGP 9.5, synaptophysine, choline acetyl transferase (ChAT), dopamine-ß-hydroxylase, VIP, CGRP, nNOS, substance P and galanin. Conclusions: These findings indicate that there is neuronal input to the episcleral circulation. ChAT and VIP as well as dopamine-ß-hydroxylase suggest parasympathetic and sympathetic innervation. Further studies are needed on whether the positively-stained structures are of functional significance for the regulation of the episcleral venous pressure and thereby IOP.

Femtosecond laser in refractive corneal surgery.

The introduction of the femtosecond (fs) laser has revolutionized ophthalmic surgery. With the worldwide application of fs-lasers, clinical outcomes and safety in corneal procedures have improved significantly and they have become an ideal tool for ultra-precise corneal refractive surgery. Flap creation in laser in situ keratomileusis (LASIK) is the most common use of this laser. It can also be used for other corneal refractive procedures including channel creation for the insertion of intrastromal corneal ring segments (ICRS), performing astigmatic keratotomies (AK), femtosecond lenticule extraction including small incision lenticule extraction (SMILE), and the insertion of corneal inlays. This article summarizes recent advanced applications of fs laser technology in corneal refractive surgery.

Effect of the outer stent position on efficacy after minimally invasive transscleral glaucoma gel stent implantation.

PURPOSE: The outer stent lumen can be located either deeper (in or under Tenon's layer) or more superficially in the conjunctival stroma after the transscleral XEN Glaucoma Gel Microstent (XEN-GGM; Allergan Plc., USA) implantation. The present study aimed to investigate the effect of the postoperative conjunctival implant position on surgical success and intraocular pressure (IOP) after XEN-GGM. METHODS: Prospective data from 66 consecutive open-angle glaucoma eyes of 54 patients were collected preoperatively and 1 and 2 weeks, and 1, 6 and 12 months postoperatively. The layer of implantation was determined in the first month postoperatively as intra- and subtenon or intraconjunctival depending on the location of the outer lumen of the stent in OCT (Visante OCT; Zeiss, Germany). Primary outcome measures were differences in relative IOP reduction at 12 months between the two groups. Further, complete and qualified surgical success, number of secondary needlings and number of IOP-lowering medications and absolute IOP were assessed. RESULTS: Relative IOP reduction was higher in intra- and subtenon group (n = 37/66, 56%) at week 1 (-54% versus -19%, p < 0.001), week 2 (-39% versus -21%, p = 0.02), month 1 (-42% versus -28%, p = 0.035) and month 12 (-39% versus -24%, p = 0.024). The mean absolute IOP was lower in intra- and subtenon group at week 1 (10.8 [95%CI, 8.8-14.1] versus 16.6 [95%CI, 14.1-19.0] mmHg, p < 0.001) and months 12 (13.9 [95%CI, 12.4-15.4] versus 16.7 [95%CI, 14.6-18.8] mmHg, p = 0.041). At month 6, a lower burden for IOP-lowering medication was shown for the intra- and subtenon group (0.2 ± 0.5 versus 1.0 ± 1.1, p = 0.034). The mean number of secondary needlings, which were done in 47/66 (71%) of the eyes, was lower in the intra- and subtenon group in the first year (1.9 ± 1.7 versus 1.2 ± 1.2, p = 0.03). Qualified surgical success was higher in the intra- and subtenon group (90% versus 61%, p = 0.01) after 1 year. CONCLUSION: The present study demonstrates a higher efficacy achieved with lower secondary needling rates in deeper implant positions in conjunctiva after XEN-GGM.

Two-year results of a multicenter study of the ab interno gelatin implant in medically uncontrolled primary open-angle glaucoma.

PURPOSE: To evaluate the effectiveness of an ab interno subconjunctival gelatin implant as primary surgical intervention in reducing intraocular pressure (IOP) and IOP-lowering medication count in medically uncontrolled moderate primary open-angle glaucoma (POAG). METHODS: In this prospective, non-randomized, open-label, multicenter, 2-year study, eyes with medicated baseline IOP 18-33 mmHg on 1-4 topical medications were implanted with (phaco + implant) or without (implant alone) phacoemulsification. Changes in mean IOP and medication count at months 12 (primary outcomes) and 24, clinical success rate (eyes [%] achieving ≥ 20% IOP reduction from baseline on the same or fewer medications without glaucoma-related secondary surgical intervention), intraoperative complications, and postoperative adverse events were assessed. RESULTS: The modified intent-to-treat population included 202 eyes (of 218 implanted). Changes (standard deviation) in mean IOP and medication count from baseline were - 6.5 (5.3) mmHg and - 1.7 (1.3) at month 12 and - 6.2 (4.9) mmHg and - 1.5 (1.4) at month 24, respectively (all P < 0.001). Mean medicated baseline IOP was reduced from 21.4 (3.6) to 14.9 (4.5) mmHg at 12 months and 15.2 (4.2) mmHg at 24 months, with similar results in both treatment groups. The clinical success rate was 67.6% at 12 months and 65.8% at 24 months. Overall, 51.1 (12 months) and 44.7% (24 months) of eyes were medication-free. The implant safety profile compared favorably with that published for trabeculectomy and tube shunts. CONCLUSIONS: The gelatin implant effectively reduced IOP and medication needs over 2 years in POAG uncontrolled medically, with an acceptable safety profile. ClinicalTrials.gov registration number: NCT02006693 (registered in the USA).

Longitudinal bleb morphology in anterior segment OCT after minimally invasive transscleral ab interno Glaucoma Gel Microstent implantation.

PURPOSE: Like the classic trabeculectomy, the minimally invasive, ab interno XEN Glaucoma Gel Microstent (XEN-GGM) creates a filtration bleb in the conjunctiva. The goal of this study was to investigate internal bleb morphology over time with anterior segment optical coherence tomography (AS-OCT) after XEN-GGM implantation. METHODS: In a prospective, single-centre, single-armed cohort study, blebs were characterized using AS-OCT in 78 eyes of 60 patients at day 1, at weeks 1 and 2 and at months 1, 3, 6, 9 and 12 after XEN-GGM implantation in patients with open-angle glaucoma. Morphological bleb characteristics were correlated with IOP and surgical success. RESULTS: Anterior segment optical coherence tomography data indicate early and late bleb changes in the course of 12 months. Uniform blebs in AS-OCTs showed higher IOPs at all examinations between week 1 (17.7 ± 4.8 mmHg versus 11.3 ± 7.1 mmHg, p = 0.001) and month 3 (16.4 ± 6.1 versus 13.4 ± 6.1, p = 0.04). Subconjunctival tissue separation bleb morphology was associated with lower mean IOPs during the course of 12 months (r = -0.75, p = 0.031). Predictors for surgical failure at month 12 were microcystic multiform bleb morphology in AS-OCT at month 3 (60% versus 15%, relative risk 4.0, p = 0.043) and uniform bleb morphology at month 9 (33% versus 23%, relative risk 1.4, p = 0.015). CONCLUSION: Bleb appearance after XEN surgery seems to be different to classic trabeculectomy literature. The present data suggest correlation of IOP and surgical long-term success with bleb morphology in AS-OCT. Prevalence of small diffuse cysts is directly associated with lower IOPs, while cystic encapsulation at 3 months predicts higher surgical failure.

Four-year results of a minimally invasive transscleral glaucoma gel stent implantation in a prospective multi-centre study.

IMPORTANCE: The transscleral XEN Glaucoma Gel Microstent (XEN-GGM, Allergan Plc., Parsippany, New Jersey) is implanted by a minimally invasive ab interno technique. BACKGROUND: The present study aims to assess the long-term clinical outcomes in patients after XEN-GGM implantation. DESIGN: This prospective, non-randomized, multi-centred study was conducted in three countries (Austria, Canada and Germany). PARTICIPANTS: Sixty-four consecutive eyes of 64 patients with open angle glaucoma received the XEN-GGM (63 µm) without Mitomycin C. Thirty-five (55%) were solo procedures, and 29 (45%) were combined with cataract surgery. METHODS: Visits were planned at baseline, 6 months, 1, 2, 3 and 4 years postoperatively. MAIN OUTCOME MEASURES: The main outcome measures were mean intraocular pressure (IOP), mean number of IOP lowering medication. Secondary outcome parameters were: visual acuity, visual fields and complete surgical failure (defined as presence of a secondary IOP lowering procedure or loss of light perception) at 4 years, postoperatively. RESULTS: Mean best-medicated baseline IOP was 22.5 ± 4.2 mmHg and decreased significantly to 13.4 ± 3.1 mmHg 4 years postoperatively (-40%, n = 34, P < 0.001). Mean number of IOP lowering medication decreased significantly from 2.4 ± 1.3 preoperatively to 1.2 ± 1.3 (-50%, n = 34, P < 0.001) postoperatively. Visual field mean deviation showed no significant change between preoperative and postoperative examinations. Complete surgical failure rate per year was 10%. CONCLUSIONS AND RELEVANCE: The XEN-GGM resulted in lower IOP and a reduction in medications from baseline over 4 years of follow-up. There was no detectable decrease in visual fields over the study. The surgical failure rate is comparable to other filtration surgeries.

Standalone Ab Interno Gelatin Stent versus Trabeculectomy: Postoperative Interventions, Visual Outcomes, and Visits.

PURPOSE: To evaluate postoperative interventions, visual outcomes, and number of postoperative office visits after standalone ab interno gelatin microstent implantation with mitomycin C (MMC) vs. trabeculectomy with MMC. DESIGN: International, multicenter, retrospective cohort study. PARTICIPANTS: A total of 354 eyes of 293 patients, including 185 microstent eyes and 169 trabeculectomy eyes. METHODS: Consecutive eyes with uncontrolled glaucoma underwent microstent or trabeculectomy surgery from January 1, 2011, through July 31, 2015, at 4 academic ophthalmology centers: Toronto, Canada; Frankfurt, Germany; Salzburg, Austria; and Leuven, Belgium. MAIN OUTCOME MEASURES: Assessed outcomes included (1) in-clinic interventions, (2) transconjunctival needle revision (TCNR), (3) postoperative visits at 1 and 3 months, (4) >2 lines vision loss at last follow-up, (5) complete visual recovery, and (6) >0.5 or >1 diopter (D) of surgically induced astigmatism. RESULTS: Ninety-five (51.4%) of the microstent eyes and 105 (62.1%) of the trabeculectomy eyes underwent an intervention by last follow-up (log-rank P = 0.0004). The most common intervention was TCNR, followed by laser suture lysis. Seventy-eight (42.2%) microstent eyes and 55 (32.5%) trabeculectomy eyes received TCNR (adjusted hazard ratio [HR], 1.73 [95% confidence interval (CI), 1.10-2.71]): 128 total TCNRs in the microstent group and 95 in the trabeculectomy group. Predictors for TCNR included prior laser peripheral iridotomy and diabetes. Microstent eyes had on average 1.00 (standard deviation 2.32) fewer visits compared with trabeculectomy eyes in the first month (P < 0.001), adjusted for baseline characteristics. The percentage of eyes that had lost >2 lines of vision at last follow-up or reoperation was 12.4% (95% CI, 8.0%-18.7%) and was 21.9% (95% CI, 15.3%-30.1%) adjusted (P = 0.0383). A higher proportion of microstent eyes regained their baseline preoperative visual acuity compared with trabeculectomy eyes (log-rank P = 0.0250; adjusted HR, 1.46 [95% CI, 1.10-2.00]). Altogether, 25.3% (95% CI, 15.3%-38.9%) of microstent eyes and 40.7% (95% CI, 27.7%-55.3%) of trabeculectomy eyes had > 0.5 D surgically induced astigmatism on an adjusted basis; 8.0% (95% CI, 3.2%-18.6%) vs. 17.3% (95% CI, 8.9%-9.8%) had >1 D. CONCLUSIONS: Microstent eyes had more TCNRs (though fewer in-clinic interventions), fewer postoperative visits, and less vision loss, and experienced less surgically induced astigmatism, than trabeculectomy eyes. Overall, the postoperative course was less intensive for the microstent, except for more TCNRs.

Intraocular Pressure Course During the Femtosecond Laser-Assisted Cataract Surgery in Porcine Cadaver Eyes.

Purpose: Femtosecond laser-assisted cataract surgery (FLACS) is an increasingly common procedure. Most laser systems require corneal applanation and thereby increase intraocular pressure (IOP). The purpose of the present study was to evaluate the IOP changes that occur during the FLACS procedure performed using the Catalys femtosecond laser system. Methods: IOP was measured by direct cannulation of the vitreous body of porcine cadaver eyes (N = 20). By inserting a second cannula connected to a water column, all the eyes were set to a baseline IOP of 20 mm Hg. The eyes were lifted by custom-made stands to achieve the appropriate height and position under the Catalys system. The standard FLACS procedure was performed using varying fragmentation times to assess the influence of tissue fragmentation times on IOP peaks. Results: We identified significant IOP elevations from baseline IOP levels during all steps of the FLACS procedure (baseline: 20.28 ± 1.32 mm Hg; vacuum: 34.48 ± 4.21 mm Hg; capture: 47.90 ± 13.02 mm Hg; lock: 48.41 ± 9.04 mm Hg; analysis: 47.15 ± 5.97 mm Hg; capsulotomy: 45.74 ± 6.52 mm Hg; fragmentation: 48.41 ± 6.80 mm Hg; end: 17.81 ± 1.61 mm Hg; all P < 0.001). Furthermore, the tissue fragmentation time had a significant effect on the peak IOP values detected (R = 0.62, P = 0.04, n = 9). Conclusions: The present study reveals significant IOP increases during FLACS procedures carried out using the Catalys system.

Efficacy, Safety, and Risk Factors for Failure of Standalone Ab Interno Gelatin Microstent Implantation versus Standalone Trabeculectomy.

PURPOSE: To compare the efficacy, safety, and risk factors for failure of standalone ab interno gelatin microstent implantation with mitomycin C (MMC) versus trabeculectomy with MMC. DESIGN: International, multicenter, retrospective interventional cohort study. PARTICIPANTS: Three hundred fifty-four eyes of 293 patients (185 microstent and 169 trabeculectomy) with no prior incisional surgery. METHODS: Consecutive eyes with uncontrolled glaucoma underwent microstent or trabeculectomy surgery from January 1, 2011 through July 31, 2015 at 4 academic ophthalmology centers: Toronto, Canada; Frankfurt, Germany; Salzburg, Austria; and Leuven, Belgium. MAIN OUTCOME MEASURES: Primary outcome measure was hazard ratio (HR) of failure, with failure defined as 2 consecutive intraocular pressure (IOP) readings of <6 mmHg with vision loss or >17 mmHg without glaucoma medications (complete success) at least 1 month after surgery despite in-clinic interventions (including needling). Secondary outcome measures included IOP thresholds of 6 to 14 mmHg and 6 to 21 mmHg and same thresholds allowing for medications (qualified success), interventions, complications, and reoperations. RESULTS: Baseline characteristics were similar, except more men (56% vs. 43%), younger patients (average, by 3 years), better preoperative visual acuity (22% vs. 32% with 0.4 logarithm of the minimum angle of resolution vision or worse), and more trabeculoplasty (52% vs. 30%) among microstent eyes. The adjusted HR of failure of the microstent relative to trabeculectomy was 1.2 (95% confidence interval [CI], 0.7-2.0) for complete success and 1.3 (95% CI, 0.6-2.8) for qualified success, and similar for other outcomes. Time to 25% failure was 11.2 months (95% CI, 6.9-16.1 months) and 10.6 months (95% CI, 6.8-16.2 months) for complete success and 30.3 months (95% CI, 19.0-∞ months) and 33.3 months (95% CI, 25.7-46.2 months) for qualified success. Overall, white ethnicity was associated with decreased risk of failure (adjusted HR, 0.49; 95% CI, 0.25-0.96), and diabetes was associated with increased risk of failure (adjusted HR, 4.21; 95% CI, 2.10-8.45). There were 117 and 165 distinct interventions: 43% and 31% underwent needling, respectively, and 50% of trabeculectomy eyes underwent laser suture lysis. There were 22 and 30 distinct complications, although most were transient. Ten percent and 5% underwent reoperation (P = 0.11). CONCLUSIONS: There was no detectable difference in risk of failure and safety profiles between standalone ab interno microstent with MMC and trabeculectomy with MMC.