The Canonical Wnt Signaling Pathway Inhibits the Glucocorticoid Receptor Signaling Pathway in the Trabecular Meshwork.

Glucocorticoid-induced glaucoma is a secondary open-angle glaucoma. About 40% of the general population may develop elevated intraocular pressure on prolonged glucocorticoid treatment secondary to damages in the trabecular meshwork (TM), a tissue that regulates intraocular pressure. Therefore, identifying the key molecules responsible for glucocorticoid-induced ocular hypertension is crucial. In this study, Dickkopf-related protein 1 (Dkk1), a canonical Wnt signaling inhibitor, was found to be elevated in the aqueous humor and TM of glaucoma patients. At the signaling level, Dkk1 enhanced glucocorticoid receptor (GR) signaling, whereas Dkk1 knockdown or Wnt signaling activators decreased GR signaling in human TM cells as indicated by luciferase assays. Similarly, activation of the GR signaling inhibited Wnt signaling. At the protein level, glucocorticoid-induced extracellular matrix was inhibited by Wnt activation using Wnt activators or Dkk1 knockdown in primary human TM cells. In contrast, inhibition of canonical Wnt signaling by ß-catenin knockdown increased glucocorticoid-induced extracellular matrix proteins. At the physiological level, adenovirus-mediated Wnt3a expression decreased glucocorticoid-induced ocular hypertension in mouse eyes. In summary, Wnt and GR signaling inhibit each other in the TM, and canonical Wnt signaling activators may prevent the adverse effect of glucocorticoids in the eye.

The future of canine glaucoma therapy.

Canine glaucoma is a group of disorders that are generally associated with increased intraocular pressure (IOP) resulting in a characteristic optic neuropathy. Glaucoma is a leading cause of irreversible vision loss in dogs and may be either primary or secondary. Despite the growing spectrum of medical and surgical therapies, there is no cure, and many affected dogs go blind. Often eyes are enucleated because of painfully high, uncontrollable IOP. While progressive vision loss due to primary glaucoma is considered preventable in some humans, this is mostly not true for dogs. There is an urgent need for more effective, affordable treatment options. Because newly developed glaucoma medications are emerging at a very slow rate and may not be effective in dogs, work toward improving surgical options may be the most rewarding approach in the near term. This Viewpoint Article summarizes the discussions and recommended research strategies of both a Think Tank and a Consortium focused on the development of more effective therapies for canine glaucoma; both were organized and funded by the American College of Veterinary Ophthalmologists Vision for Animals Foundation (ACVO-VAF). The recommendations consist of (a) better understanding of disease mechanisms, (b) early glaucoma diagnosis and disease staging, (c) optimization of IOP-lowering medical treatment, (d) new surgical therapies to control IOP, and (e) novel treatment strategies, such as gene and stem cell therapies, neuroprotection, and neuroregeneration. In order to address these needs, increases in research funding specifically focused on canine glaucoma are necessary.

Episcleral Venous Fluid Wave Correlates with Trabectome Outcomes: Intraoperative Evaluation of the Trabecular Outflow Pathway.

PURPOSE: To determine whether the characteristics of an intraoperative episcleral venous fluid wave (EVFW), a potential indicator of trabecular outflow patency, correlates with Trabectome (NeoMedix Corp, Tustin, CA) outcomes. DESIGN: Retrospective, observational study. PARTICIPANTS: A total of 68 eyes of 49 patients with glaucoma who underwent phaco-Trabectome (63 eyes) or Trabectome alone (5 eyes). METHODS: The EVFW was evaluated in a masked fashion for wave degree (0-4) and clock hours (0-6). A diffuse EVFW (4, 5, 6 clock hours) was a near complete blanching of the episcleral vasculature, and a poorly defined wave was minimal change in the vasculature. Patients were grouped into wave categories to determine whether there was a correlation with postoperative intraocular pressure (IOP). Patients requiring further glaucoma surgery were considered failures. MAIN OUTCOME MEASURES: Degree and extent of EVFW, IOP, and glaucoma medications. RESULTS: For all eyes, there was a statistically significant correlation between wave clock hours and postoperative IOP at month 1 (P = 0.043) and month 3 (P = 0.002), but not a statistically significant correlation at month 6 (P = 0.12) or 1 year (P = 0.86). A strong correlation was found among IOP, medications, and EVFW in eyes with an extensive EVFW when compared with eyes with a poorly defined EVFW. At 12 months, the mean IOP in the extensive EVFW group was 13.3±2.7 mmHg on 1.4±1.2 medications compared with an IOP of 18.4±3.1 mmHg on 2.9±0.9 medications in the poorly defined group (both P = 0.001). Overall, 5 of 68 eyes (7%), required further glaucoma surgery. Eyes with a poorly defined EVFW had a higher likelihood of further glaucoma surgery (36%). CONCLUSIONS: The EVFW is an intraoperative gauge of patency through the trabecular outflow pathway. Absence of the EVFW implies obstruction in the collector channel-intrascleral aqueous outflow pathway, preventing flow to the visible episcleral veins. In contrast, eyes with a diffuse EVFW had sufficient flow through their collector channels, had a lower IOP, required fewer glaucoma medications, and had a lower requirement for further glaucoma surgery. The characteristics of an EFVW may be able to predict surgical outcomes after Trabectome surgery.

Gonioscopy-assisted transluminal trabeculotomy, ab interno trabeculotomy: technique report and preliminary results.

PURPOSE: To introduce a minimally invasive, ab interno approach to a circumferential 360-degree trabeculotomy and to report the preliminary results. DESIGN: Retrospective, noncomparative cases series. PARTICIPANTS: Eighty-five eyes of 85 consecutive patients who sought treatment at Glaucoma Associates of Texas with uncontrolled open-angle glaucoma and underwent gonioscopy-assisted transluminal trabeculotomy (GATT) for whom there was at least 6 months of follow-up data. METHODS: Retrospective chart review of patients who underwent GATT by 4 of the authors (D.S.G., D.G.G., O.S., R.L.F.) between October 2011 and October 2012. The surgery was performed in adults with various open-angle glaucomas. MAIN OUTCOME MEASURES: Intraocular pressure (IOP), glaucoma medications, visual acuity, and intraoperative as well as postoperative complications. RESULTS: Eighty-five patients with an age range of 24 to 88 years underwent GATT with at least 6 months of follow-up. In 57 patients with primary open-angle glaucoma, the IOP decreased by 7.7 mmHg (standard deviation [SD], 6.2 mm Hg; 30.0% [SD, 22.7%]) with an average decrease in glaucoma medications of 0.9 (SD, 1.3) at 6 months. In this group, the IOP decreased by 11.1 mmHg (SD, 6.1 mmHg; 39.8% [SD, 16.0%]) with 1.1 fewer glaucoma medications at 12 months. In the secondary glaucoma group of 28 patients, IOP decreased by 17.2 mmHg (SD, 10.8 mmHg; 52.7% [SD, 15.8%]) with an average of 2.2 fewer glaucoma medications at 6 months. In this group, the IOP decreased by 19.9 mmHg (SD, 10.2 mmHg; 56.8% [SD, 17.4%]) with an average of 1.9 fewer medications (SD, 2.1) at 12 months. Treatment was considered to have failed in 9% (8/85) of patients because of the need for further glaucoma surgery. The cumulative proportion of failure at 1 year ranged from 0.1 to 0.32, depending on the group. Lens status or concurrent cataract surgery did not have a statistically significant effect on IOP in eyes that underwent GATT at either 6 or 12 months (P > 0.35). The most common complication was transient hyphema, seen in 30% of patients at the 1-week visit. CONCLUSIONS: The preliminary results and safety profile for GATT, a minimally invasive circumferential trabeculotomy, are promising and at least equivalent to previously published results for ab externo trabeculotomy.

Difficult decisions, filtration surgery, and the heartbreak of the numerator.

A 70-year-old man had progressive and severe glaucoma in each eye. He was intolerant to dorzolamide, brimonidine, and netarsudil. Each eye had prior selective laser trabeculoplasty (SLT) as well as phacoemulsification plus minimally invasive glaucoma surgery (MIGS) 6 years before current presentation (iStent [Glaukos Corp.] in the right eye and Cypass [Alcon Laboratories, Inc.] in the left eye). Postoperative acuities were 20/20 and 20/25 in the right and left eyes, respectively. When his left eye progressed with loss of central acuity despite peak intraocular pressures (IOPs) in the middle to upper teens, neuro-ophthalmology consultation was obtained (Figure 1JOURNAL/jcrs/04.03/02158034-202401000-00017/figure1/v/2023-12-22T124801Z/r/image-tiff). That workup included magnetic resonance imaging scan and hematologic screening, but all results were negative, and the neuro-ophthalmic consultant concluded that the vision loss was likely on the basis of glaucoma. Accordingly, a trabeculectomy was performed in the left eye achieving consistent IOPs in the range of 7 to 10 mm Hg without medications, rending the left eye stable since the filtration surgery nearly 2 years previously. The right eye continued to progress both subjectively and objectively, and on recent examination, the IOP measured 20 mm Hg and 09 mm Hg in the right and left eyes, respectively (Figure 2JOURNAL/jcrs/04.03/02158034-202401000-00017/figure2/v/2023-12-22T124801Z/r/image-tiff). Medications included timolol and latanoprostene bunod in the right eye only. Central corneal thickness was 526 µm and 527 µm in the right and left eyes, respectively. The visual acuity now measured 20/25 in the right eye and 20/250 in the left eye. The vertical cup-to-disc ratio was 0.9 in the right eye and 1.0 in the left eye. Gonioscopy revealed a wide open angle in each eye with a patent sclerostomy superiorly in the left eye. The conjunctiva and sclera were healthy and without scarring in the right eye. The bleb in the left eye was diffuse, lightly vascularized, and seidel negative. Axial length (AL) was 26.88 µm in the right eye and 26.77 µm in the left eye. The patient was in good health and was not anticoagulated. An extensive discussion ensued about the best course of action for the right eye. How would you proceed in managing definite progression in this individual's right eye, knowing that he had lost fixation in his left eye at similar pressures?

A Health-Related Quality of Life Measure for Patients Who Undergo Minimally Invasive Glaucoma Surgery.

PURPOSE: To develop a patient-reported outcome measure to assess the impact of glaucoma and treatment, including minimally invasive glaucoma surgery (MIGS). DESIGN: Observational study before and after concomitant cataract and Food and Drug Administration-approved implantable MIGS device surgery. SETTING: Survey administration was on a computer, iPad, or similar device. PATIENT POPULATION: 184 adults completed the baseline survey, 124 a survey 3 months after surgery, and 106 the 1-month test-retest reliability survey. The age range was 37 to 89 (average age = 72). Most were female (57%), non-Hispanic White (81%), and had a college degree (56%). MAIN OUTCOME MEASURES: The Glaucoma Outcomes Survey (GOS) assesses functional limitations (27 items), vision-related symptoms (7 items), psychosocial issues (7 items), and satisfaction with microinvasive glaucoma surgery (1 item). These multiple-item scales were scored on a 0 to 100 range, with a higher score indicating worse health. RESULTS: Internal consistency reliability estimates ranged from 0.75 to 0.93, and 1-month test-retest intraclass correlations ranged from 0.83 to 0.92 for the GOS scales. Product-moment correlations among the scales ranged from 0.56 to 0.60. Improvement in visual acuity in the study eye from baseline to the 3-month follow-up was significantly related to improvements in GOS functional limitations (r = 0.18, P = .0485), vision-related symptoms (r = 0.19, P = .0386), and psychosocial concerns (r = 0.18, P = .0503). Responders to treatment ranged from 17% for vision-related symptoms to 48% for functional limitations. CONCLUSIONS: This study supports using the GOS for ophthalmic procedures such as MIGS. Further evaluation of the GOS in different patient subgroups and clinical settings is needed.

iSTAT (Intraluminal Suture Transfixed and Titratable) technique for ligature-free Reversal of long-term drainage implant hypotony.

Purpose: To describe the iSTAT (Intraluminal Suture Transfixed and Titratable) technique, an improvement on prior tube occlusion methods, allowing for variable flow. Observations: A 76-year-old woman who underwent an uncomplicated glaucoma drainage device (GDD) placement for uncontrolled mixed mechanism glaucoma presented with hypotony 4 years post-operatively. The iSTAT technique was performed to adjust the flow in the GDD tube: a 4-0 polypropylene suture tip was blunted with a low-temperature cautery, creating a bulbed end that would occlude the tube. The suture was introduced into the tube bulb-first intracamerally, extending to the plate. If partial occlusion of the tube is desired, the suture can be secured in place by piercing the side wall of the tube tip with the distal end of the suture. After complete occlusion of the GDD tube with a large bulb, the patient had intraocular pressures (IOPs) > 40 mmHg on post-operative day 1, which remained in the 25-30 mmHg range 2-3 weeks post-operatively on maximally tolerated medications. Patient underwent a second revision with a smaller-bulbed stent (with a 3-0 polypropylene suture), which stabilized her IOP at 8 mmHg. Conclusion and Importance: The iSTAT technique allows for an ab interno revision, titration of flow, and stabilization of the stent in the wall of the tube. The ab interno approach precludes the need for conjunctival incisions, thus maintaining bleb integrity and permitting surgery under topical anesthesia. The intracameral stabilization of the stent in the tube allows for smaller bulbs to titrate the flow without external ligatures.

Outcomes of bleb revision with ologen following filtering glaucoma surgery.

PURPOSE: This study reports long-term outcomes of bleb revision with ologen™ Collagen Matrix (Aeon Astron Europe BV, the Netherlands) for the surgical management of various bleb-related issues including persistent bleb leaks with or without associated hypotony, bleb dysesthesia, overhanging blebs, or hypotony after filtering glaucoma surgery. MATERIALS AND METHODS: A retrospective chart review was performed for patients who underwent ologen bleb revision from 2012 to 2019 at Glaucoma Associates of Texas. RESULTS: The study included 23 eyes of 22 patients undergoing bleb revision with the ologen implant. Mean age was 74.0 ± 11.3 years, 16 (69.6%) were female, and 13 (56.5%) were White. Indications for bleb revision included bleb leak (78.3%), dysesthesia (13.0%), and hypotony from an overfiltering bleb (8.7%). Mean preoperative intraocular pressure was 6.8 ± 4.1 mmHg and the number of medications was 0.3 ± 0.9. Median follow-up was 24 months (range: 12-84 months); all patients had at least 12 months of follow-up. At 1 year, mean intraocular pressure was 10.9 ± 4.6 mmHg on 0.2 ± 0.5 medications, and at last follow-up, mean intraocular pressure was 10.4 ± 3.6 mmHg on 0.3 ± 0.7 medications. Bleb morphology remained low, diffuse, and posterior. One patient developed kissing choroidal effusions requiring surgical drainage with subsequent stabilization of intraocular pressure and bleb function, and three patients required additional surgery due to persistent leaks or bleb failure; there were no other vision-threatening complications. CONCLUSIONS: Use of the ologen implant during surgical bleb revision is a useful surgical technique that confers long-term improvements in bleb morphology and stability of function.

Twenty-Four-Month Outcome of Gonioscopy-Assisted Transluminal Trabeculotomy (GATT) in Eyes With Prior Corneal Transplant Surgery.

PURPOSE: Glaucoma is a well-known sequelae of corneal transplant surgery and is a leading cause of visual loss in this patient group. We evaluated the performance and safety of gonioscopy-assisted transluminal trabeculotomy (GATT) in this population. DESIGN: Noncomparative retrospective case series. PARTICIPANTS: Consecutive eyes of patients receiving the GATT procedure for uncontrolled intraocular pressure (IOP) following corneal transplant surgery from 2016 to 2019. METHODS: Retrospective analysis of eyes with a history of prior corneal transplant undergoing GATT at Glaucoma Associates of Texas between 2016 and 2019 was performed. Data included IOP, patient demographics, preoperative and postoperative medications, preoperative and postoperative corneal procedures, complications, and need for reoperation for IOP control. MAIN OUTCOME MEASURES: IOP reduction and medication use following the procedure. RESULTS: Thirty-nine eyes of 32 patients with prior corneal transplant surgery underwent a GATT procedure. Prior corneal surgery included penetrating keratoplasty (59.0%), Descemet's stripping endothelial keratoplasty (35.9%), Descemet's membrane endothelial keratoplasty (2.6%), and deep anterior lamellar keratoplasty (2.6%). Patient age ranged from 24 to 94 years (mean 68.0 y) with 44% female and 81% Caucasian. The majority of patients had secondary open angle glaucoma (64.1%). There was a significant reduction in IOP and number of medications at all postoperative time points after censoring patients requiring reoperation to control IOP (P<0.001). At 24 months the pressure decreased from baseline of 30.9±11.5 to 13.9±4.7 mm Hg. Medications decreased from 4.2±1.0 medications at baseline to 0.6±1.0 at 24 months. Visual acuities decreased significantly over the first postsurgical month (all P<0.05), but these recovered at subsequent follow-up visits with 2-Snellen line improvements exceeding losses from month 3 to 36. Seven eyes required reoperation for uncontrolled glaucoma at a median of 8.5 months (range: 1.6 to 16.2 mo) after GATT. The cumulative proportion of eyes undergoing repeat cornea surgery was 2.6%, 2.6%, and 14.3% at 12, 24, and 36 months post-GATT, respectively. CONCLUSIONS: This case series describes a group of glaucoma patients, with a history of prior corneal surgery, that were safely and successfully treated with GATT. While classically traditional glaucoma surgeries are considered the standard of care for eyes following corneal transplant surgery, GATT should be considered as a reasonable, safe and effective alternative for surgically lowering IOP.

Rescue of Failed XEN-45 Gel Implant by Nd:YAG Shock Wave to Anterior Chamber Tip to Dislodge Hidden Intraluminal Occlusion.

PURPOSE: The purpose of this study was to inform ophthalmic surgeons in a timely manner of the hidden problem of clear intraluminal cellular debris as a cause for XEN-45 failure and to describe low energy neodymium-doped yttrium aluminum garnet (Nd:YAG) laser revision with periluminal anterior chamber tip shockwave treatment to improve flow to the bleb. PATIENTS AND METHODS: Six patients with visibly patent stent lumen post XEN-45 surgery. These eyes developed rising intraocular pressure (IOP) with a history of excellent prior bleb formation and were treated successfully with Nd:YAG laser shockwave therapy to disperse assumed intraluminal cellular debris. The laser was aimed just anterior and axial to the intracameral tip of the gel stent through a gonioscopy lens. RESULTS: Six patients with an average age of 75 years (60 to 90 y), preoperative IOP of 30 mm Hg (16 to 52 mm Hg) on an average of 2 antiglaucoma medications (0 to 4) underwent periluminal anterior chamber tip shock wave at an average of 12 months (1 to 38 mo) from XEN-45 surgery. The IOP was immediately reduced to an average of 15 mm Hg (8 to 23 mm Hg) and last IOP averaged 15 mm Hg (10 to 23 mm Hg) on 1.5 medications (0 to 4) at 4 months post periluminal anterior chamber tip shock wave. CONCLUSION: Nd:YAG laser revision of hidden blockage of a XEN-45 gel implant with periluminal anterior chamber tip shockwave treatment can disperse invisible intraluminal cellular debris and improve flow in a failing XEN-45 microstent, especially when distal fibrosis is not excessive.

Vision-Targeted Health-Related Quality-of-Life Survey for Evaluating Minimally Invasive Glaucoma Surgery.

PURPOSE: To develop a vision-targeted health-related quality-of-life instrument for patients with glaucoma who are candidates for minimally invasive glaucoma surgery (MIGS). DESIGN: Development of a health-related quality-of-life instrument. PARTICIPANTS: Twelve practicing ophthalmologists and 41 glaucoma patients. METHODS: A questionnaire was constructed to assess functional limitations, vision-related symptoms, aesthetics, psychosocial issues, and surgical satisfaction for MIGS candidates. Questions were drafted after a review of the literature and subsequently refined based upon input from 1 physician and 4 patient focus groups. Nineteen cognitive interviews were used to ensure that questions were understandable to respondents. RESULTS: The focus group identified the following key issues and concerns as being important to glaucoma patients: functional limitations (eg, driving), bodily discomfort (eg, stinging from drops), changes in appearance (eg, drooping eyelid), and psychosocial concerns (eg, mental burden associated with a diagnosis of glaucoma, financial burden of treatment). Cognitive interviews resulted in the following improvements to the questionnaire: changes in wording to clarify lighting conditions, and additional questions addressing psychosocial issues, such as job loss, severity of disease, and perception of MIGS. CONCLUSIONS: A patient-reported outcomes instrument, the Glaucoma Outcomes Survey, was developed to evaluate MIGS for patients with mild to moderate glaucoma. Next steps include electronic administration to patients selected from the American Academy of Ophthalmology Intelligent Research in Sight (IRIS) registry. An electronic patient-reported outcomes platform will be used to administer the questionnaire before and after MIGS. The questionnaire will improve understanding of how surgical interventions such as MIGS impact vision-targeted health-related quality-of-life in glaucoma patients.

Historical Considerations and Innovations in the Perioperative Use of Mitomycin C for Glaucoma Filtration Surgery and Bleb Revisions.

Although there is a currently a revolution in angle-based procedures, subconjunctival filtration surgery with mitomycin C (MMC) wound modification remains a vital skill for glaucoma surgeons. MMC is a potent antifibrotic agent that has been an invaluable adjunct for successful glaucoma filtration surgery for over 20 years, but it must be used judiciously to avoid serious complications, including hypotony, corneal decompensation, bleb avascularity, bleb leaks, blebitis, and endophthalmitis. The purpose of this report is to describe the historical lessons learned from MMC use, along with updated methods of MMC delivery during primary trabeculectomy, bleb needling at the slit lamp, bleb revisions in the operating room, and newer and less invasive ab-interno filtering procedures. Information for the review was gathered using an extensive search on PubMed, a review of all available peer-reviewed literature, and the authors' personal clinical judgment and experience.

Reticular Corneal Edema or Corneal Honeycombing in Eyes Treated With Netarsudil: A Case Series.

This is a descriptive case series of 3 patients with uncontrolled intraocular pressure that developed reticular corneal changes after initiating netarsudil (0.02%). In all cases, upon observing reticular corneal edema, netarsudil (0.02%) was stopped followed by disappearance of corneal honeycombing. With the increasing use of this novel glaucoma medication, potentially more rare side effects will be observed. Reticular corneal edema or corneal honeycombing is an ocular examination finding that can rarely occur after initiating netarsudil (0.02%) regardless of prior corneal edema status. In our experience, the reticular changes resolve upon cessation of netarsudil.

XEN Gel Stent in Pediatric Glaucoma.

PURPOSE: To report a series of 3 eyes of 3 children with congenital glaucoma receiving the XEN gel stent implant. PATIENTS AND METHODS: An interventional case series is reported. RESULTS: Three eyes underwent implantation of the gel stent. In 2 cases, the gel implant procedure was performed after failed trabeculotomy, while in the third eye, primary gel stent implantation was performed. One eye received 2 implants. Three procedures were performed via an ab interno approach while the fourth was performed ab externo. No device-related complications were observed. In all 3 eyes, intraocular pressure was controlled without the use of topical medications through 6 to 24 months of follow-up. CONCLUSIONS: The gel stent implant can be safely used in children with congenital glaucoma and effectively lowers intraocular pressure in these eyes. This procedure is a viable follow-up to, or replacement for, traditional angle surgery in eyes with congenital glaucoma.

Canal surgery in adult glaucomas.

PURPOSE OF REVIEW: Outflow procedures for glaucoma surgery have remained popular in the last decade, including trabeculectomy, glaucoma drainage devices, and deep sclerectomy/viscocanalostomy. In the last few years, the surgical armamentarium for glaucoma has vastly increased. Surgeons are using more procedures aimed at creating bleb-free surgery. Schlemm's canal surgery is experiencing a renaissance. This article concentrates on three of the more commonly performed canal procedures: trabeculotomy ab interno (Trabectome), Canaloplasty, and trabeculotomy ab externo. RECENT FINDINGS: Trabeculotomy ab interno performed with the Trabectome has been shown to lower intraocular pressure (IOP) almost 40% by 12 months with minimal complications. Trabectome alone, as well as combined with cataract surgery, appears to lower IOP quite well. Canaloplasty has also been shown to lower IOP by 38% and combined with cataract surgery, IOP was lowered 44% at 24 months. Trabeculotomy lowers IOP well, especially in older adults. Phacotrabeculotomy lowers IOP to 21 mmHg or less in 84% of patients with supplemental use of medications, and in 36% of patients without at 3 years. SUMMARY: Canal surgery has proven to be an alternative to traditional glaucoma surgery, lowering IOP relatively well. Surgeons must be comfortable with the anatomy and proceed with the procedure in eyes that are amenable to various new surgical advances.

Episcleral Venous Fluid Wave in the Living Human Eye Adjacent to Microinvasive Glaucoma Surgery (MIGS) Supports Laboratory Research: Outflow is Limited Circumferentially, Conserved Distally, and Favored Inferonasally.

PURPOSE: The purpose of this study was to describe downstream patterns of outflow with the episcleral venous fluid wave (EVFW) in the living human eye adjacent to microinvasive glaucoma surgery (MIGS) and determine if the EVFW supports existing ex-vivo laboratory outflow research. DESIGN: Retrospective, noncomparative case series. PATIENTS: A total of 10 eyes of 10 patients who underwent phaco-Trabectome and 10 eyes of 10 patients who underwent phaco-iStent consecutively at Glaucoma Associates of Texas for cataract and uncontrolled glaucoma who demonstrated an episcleral wave. METHODS: The EVFW was visualized and recorded during irrigation and aspiration. To describe the hydrodynamic properties of the fluid wave, its degrees, extent, and characteristics were measured with a protractor in Photoshop. RESULTS: The incised Trabectome arc produced adjacent episcleral blanching of 134±11 degrees (range, 112 to 150 degrees) with an additional 54 degrees of marginal recruitment (41 degrees inferonasal plus 13 degrees superonasal) adjacent to the ends of the Trabectome incision. The mean episcleral blanch for the iStent was 51±19 degrees (range, 19 to 90 degrees), comprised of 29 degrees inferonasal plus 22 degrees superonasal. CONCLUSIONS: Downstream episcleral flow in the living human eye adjacent to the iStent is variable and mainly confined to 2 clock hours indicating a lack of significant circumferential flow in glaucomatous eyes. Flow distal to the Trabectome site encompasses the Trabectome incisional arc with an additional 2 clock hours of lateral fluid wave favoring the inferonasal over superonasal quadrant 3 to 1. These in-vivo findings made visible with MIGS, corroborate recent in-vivo and long-standing ex-vivo laboratory research that outflow is largely segmented, favored inferonasally and conserved distally.

Early Results of Goniotomy with the Kahook Dual Blade, a Novel Device for the Treatment of Glaucoma.

PURPOSE: To report the outcomes of patients who underwent goniotomy with the Kahook Dual Blade (KDB) either as a standalone procedure or in combination with cataract extraction. PATIENTS AND METHODS: This retrospective chart review included 111 eyes of 90 patients who underwent KDB goniotomy from January to November 2016 at Glaucoma Associates of Texas. KDB goniotomy was combined with cataract surgery in 100 eyes. The main outcome measures were postoperative intraocular pressure (IOP) and number of IOP lowering medications. RESULTS: Preoperatively, mean IOP was 17.1 ± 4.7 mmHg (range 8-34 mmHg) and mean number of IOP lowering medications was 2.4 ± 1.3 (range 0-6). Postoperatively, mean IOP was 14.9 mmHg, 13.9 mmHg, 14.1 mmHg, 14.4 mmHg, and 14.7 mmHg at 1, 3, 6, 9, and 12 months follow-up, respectively (all p <0.004). Mean numbers of IOP lowering medications were 0.8, 1.0, 1.0, 1.0, and 1.6 at 1, 3, 6, 9, and 12 months follow-up, respectively (all p <0.001). The cumulative reoperation rates for uncontrolled IOP after KDB were 0%, 1.0%, 2.1%, and 4.6% at 3, 6, 9, and 12 months, respectively. Eyes with a preoperative IOP >21 mmHg were significantly more likely to undergo reoperation (p = 0.038, log-rank test). There were no serious complications at any time point in the follow-up period. CONCLUSION: The Kahook Dual Blade results in a reduction in IOP and use of glaucoma medications after one year of follow-up. Further prospective studies are needed to fully characterize safety and efficacy.

Gonioscopy-assisted Transluminal Trabeculotomy: An Ab Interno Circumferential Trabeculotomy: 24 Months Follow-up.

PURPOSE: The purpose of this study was to provide 24-month follow-up on surgical success and safety of an ab interno circumferential 360-degree trabeculotomy. METHODS: Chart review of patients who underwent a gonioscopy-assisted transluminal trabeculotomy (GATT) procedure was performed by 4 of the authors (D.S.G., O.S., R.L.F., and D.G.G.). The surgery was performed in adults with various types of open-angle glaucoma with preoperative intraocular pressures (IOPs) of ≥18 mm Hg. RESULTS: In total, 198 patients aged 24 to 89 years underwent the GATT procedure with at least 18 months follow-up. Patients with primary open-angle glaucoma had an average IOP decrease of 9.2 mm Hg at 24 months with an average decrease of 1.43 glaucoma medications. The mean percentage of IOP decrease in these primary open-angle glaucoma groups at 24 months was 37.3%. In secondary open-angle glaucoma, at 24 months there was an average decrease in IOP of 14.1 mm Hg on an average of 2.0 fewer medications. The mean percentage of IOP decrease in the secondary open-angle glaucoma groups at 24 months was 49.8%. The cumulative proportion of failure at 24 months ranged from 0.18 to 0.48, depending on the group. In all 6 study groups, at all 5 postoperative time points (3, 6, 12, 18, and 24 mo) the mean IOP and reduction in glaucoma medications was significantly reduced from baseline (P<0.001) with the exception of one time point. CONCLUSIONS: The 24-month results demonstrate that GATT is relatively safe and effective in treating various forms of open-angle glaucoma. The long-term results for GATT are relatively equivalent to those previously reported for GATT and ab externo trabeculotomy studies.