Computed perimetry remains the gold standard of visual field measurement among glaucoma patients. However, several emerging technologies, made possible by advances in computer programming, smartphone, tablet, or virtual reality, allow alternative means of visual function assessment. These new visual tests may one day have a useful complementary role in visual field testing and to bridge the gap between perimetry and daily experience. Many of these emerging technologies have distinct practical advantages over Ganzfield bowl-based computed perimetry. This paper outlines a discussion of some of these emerging techniques in visual function assessment in glaucoma.
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Tamçelik N, Capar O, Atalay E. Modified Viscotrabeculotomy with Microcatheter: Our Technique and Experience in the Surgical management of Glaucoma. J Curr Glaucoma Pract 2019; 13 (3):88-93.
Aims: To present the results of our case series with a technique we defined as “modified viscotrabeculotomy” which incorporates the benefits of 360° of trabeculotomy and viscodilation and viscodissection of canal of Schlemm using a microcatheter.
Materials and methods: This study was designed as a prospective interventional case series and was conducted in Cerrahpasa Medical School Ophthalmology Clinic. Forty-one eyes of 30 patients diagnosed with congenital glaucoma (CG) underwent modified viscotrabeculotomy surgery following initial preoperative examination. The main outcome measure was the surgical success of the procedure, which is determined by an intraocular pressure (IOP) of <18 mm Hg without medication or resurgery; qualified success is defined as an IOP of <18 mm Hg under general anesthesia with an additional need for medications. The differences in IOP measurements were analyzed using paired analysis of variance (ANOVA) with repeated measures.
Results: The mean preoperative IOP of the patients was 32.27 ± 4.89 mm Hg. The IOP values at the 1st, 3rd, 6th postoperative months, and at the last visit were 13.41 ± 2.25 mm Hg, 13.70 ± 1.78 mm Hg, 12.47 ± 1.57 mm Hg, and 12.26 ± 1.81 mm Hg, respectively. The difference between the preoperative IOP values and postoperative IOP values was statistically significant (p < 0.001). The qualified surgical success rate was 94.4% after a mean follow-up of 27.95 ± 8.25 months (range 15–45 months).
Conclusion: Modified viscotrabeculotomy is a safe and effective treatment in the management of CG.
Woravipa Na Ayudhya,
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Hirunpatravong P, Kasemsup T, Ayudhya WN, Apiwattanasawee P. Long-term Effect of Continuous Positive Air Pressure Therapy on Intraocular Pressure in Patients with Primary Open-angle Glaucoma with Obstructive Sleep Apnea. J Curr Glaucoma Pract 2019; 13 (3):94-98.
Purpose: Prevalence of glaucoma is higher in obstructive sleep apnea (OSA) patients. The gold standard technique to treat OSA is continuous positive airway pressure (CPAP) therapy. The influence of long-term CPAP therapy on intraocular pressure (IOP), blood pressure, ocular perfusion pressure (OPP), and glaucoma progression in primary open-angle glaucoma (POAG) patients was evaluated.
Design: Prospective study.
Materials and methods: In this study, we enrolled 12 eyes from six POAG patients aged >35 years, with newly diagnosed OSA and with indication for CPAP therapy. The CPAP was performed for 12 months. We monitored the IOP every 3 months. Visual field was determined at baseline and 12 months.
Results: The mean IOP after CPAP therapy for 12 months was significantly higher than the mean baseline IOP (average IOP 3 months before CPAP therapy) (19.08 ± 3.47 vs 17.83 ± 2.88 mm Hg; p = 0.006). The IOP rising rate was 0.69 ± 0.47/years (p = 0.138) before CPAP therapy and increased to 1.13 ± 0.47/years (p = 0.016) after CPAP therapy. The OPP after 12 months of CPAP was significantly lower than the baseline (42.21 ± 5.29 vs 45.24 ± 7.09 mm Hg; p = 0.06). Results showed that the pattern standard deviation (PSD) value of 24-2 short wavelength automated perimetry (SWAP) visual field was reduced from 5.34 ± 3.92 to 4.77 ± 3.73 (p = 0.025). Antiglaucoma medication was administered to a patient due to increased IOP without glaucoma progression evidence.
Conclusion: The POAG and OSA patients demonstrated significant IOP rising after CPAP therapy but did not show progression of glaucomatous damage. Mean deviation (MD), PSD, and visual field index (VFI) were not significantly different after CPAP therapy.
Précis: Prospective study of POAG and OSA patients demonstrated significant IOP rising after CPAP therapy for a year. The study did not show progression of glaucomatous damage.
Purpose: The suprachoroidal pathway can potentially provide a viable target for intraocular pressure (IOP) control. We present efficacy and safety result for the CyPass® Micro-Stent that provides insight into the use of the suprachoroidal space for IOP reduction.
Materials and methods: A retrospective, noncomparative audit of patient records in a university-affiliated National Health Service (NHS) hospital between June 2017 and August 2018. Main outcome measures were IOP reduction and the number of glaucoma drops taken at each time point. Failure and adverse events were noted for each patient.
Results: Seventy-seven consecutive case records of 69 patients underwent the CyPass® procedure between August 2017 and August 2018. A stand-alone procedure was performed in 37 (58%) of cases and combined phacoemulsification and CyPass® procedures were performed in 27 (42%) of cases. At baseline, the mean IOP was 24.6 ± 7.2 mm Hg. The mean IOP at 12 months’ follow-up was 16.4 ± 4.5 mm Hg (p < 0.05). At baseline, the mean number of medications was 2.41 ± 0.98, which decreased at 12 months to 1.1 ± 1.3 (p < 0.05). Best corrected visual acuity analysis did not show statistically significant change preoperatively and at each postoperative time point. At 12 months’ postoperative time point, 24% of eyes had failed. Significant IOP spikes were noted in 18 (28.1%) of cases.
Conclusion: The suprachoroidal pathway appears to potentially offer an alternative to the classic subconjunctival pathways, yet present a new set of challenges. Further studies would have to address these concerns of endothelial cell loss, IOP spikes, and high failure rate.
Aim: Our goal is to review current literature regarding drug-induced acute angle-closure glaucoma (AACG) and provide ophthalmologists and general practitioners with a thorough understanding of inciting medications and treatment pitfalls to be avoided.
Background: Drug-induced AACG is an ophthalmological emergency that ophthalmologists and general practitioners should be familiar with, given its potentially blinding consequences. Common anatomical risk factors for AACG include a shallow anterior chamber depth, short axial length, plateau iris configuration, thick lens, anteriorly positioned lens, and rarely, intraocular tumor. Demographic risk factors include female sex, Asian ethnicity, family history, and advanced age. In patients with predisposing factors, acute angle closure can be triggered by various classes of medications including adrenergic agonists, anticholinergics, cholinergics, sulfonamides, supplements, and serotonergic medications. Physicians prescribing such inciting medications should be aware of their potentially sight-threatening adverse effects and to inform patients of the warning symptoms. Patients typically present with elevated intraocular pressure (IOP), headache, nausea, blurry vision, and halos around lights.
Review results: There are two main mechanisms of drug-induced AACG, both with different treatment strategies. The first mechanism of drug-induced AACG is pupillary block and iridocorneal angle closure secondary to thickening of iris base with mydriasis. The second mechanism of drug-induced AACG is anterior displacement of the lens–iris diaphragm due to mass effect (e.g., blood, misdirected aqueous humor, and tumors), uveal effusion, or weakened zonules.
Conclusion: This paper reviews drug-induced AACG, high-risk anatomical features, underlying mechanisms, inciting medications, and options for treatment and prevention.
Clinical significance: With proper understanding of the underlying mechanism of drug-induced AACG, physicians can respond promptly to save their patients’ vision by employing the correct treatment strategy.
Giorgio E Bravetti,
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Gillmann K, Mansouri K, Bravetti GE, Mermoud A. Baerveldt–Baerveldt Apposition: A New Surgical Technique to Salvage Obstructed Glaucoma Drainage Tubes. J Curr Glaucoma Pract 2019; 13 (3):110-112.
Aim: Glaucoma drainage device (GDD) failure is usually rectified by the replacement of the entire device or using a tube extender, both of which were associated with postoperative complications. To minimize these risks, we developed a technique to replace the failing section of a tube while keeping the filtration plate in place, and without resorting to an extender clip.
Background: We describe the case of a 69-year-old man, whose left posttraumatic glaucoma was initially treated with a XEN-augmented Baerveldt procedure. Following recurrent obstructions, a kinked section of the Baerveldt tube was sectioned and replaced.
Technique: After sectioning the blocked section of the tube, a new Baerveldt tube was inserted into the anterior chamber. Its filtration plate was removed, and the posterior end of the new tube was connected to the anterior end of the existing device so that both lumens would be continuous. The adjoining tubes were stitched to each other with two 8-0 nylon sutures passing through the walls of the tubes. An allograft patch was replaced over the tubes and the conjunctival fornix was closed. Intraocular pressure (IOP) normalized immediately after surgery and remained stable through 6 months.
Conclusion: This surgical approach offers a new way to salvage a failing Baerveldt tube without replacing the filtration plate, repeating a complete surgery, or potentially compromising the conjunctiva with an extender. The minimal residual gap at the junction between the tubes appears to provide the same additional IOP-lowering effect as the “venting slits” that are sometimes performed to minimize the initial hypertensive phase without causing hypotony.
Clinical significance: This report illustrates a simple yet effective technique to replace the failing section of a GDD or lengthen a short GDD without replacing the entire device or using an extender clip, and thus minimizing the risks of complications.
Giorgio E Bravetti,
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Gillmann K, Bravetti GE, Mansouri K. Delayed Obstruction of XEN Gel Stent by Cell Debris in Primary Open-angle Glaucoma: A New Insight into the Pathophysiology of Filtration Device Failure. J Curr Glaucoma Pract 2019; 13 (3):113-115.
Aim: The aim of this report is to explore the risk factors of XEN stent obstruction, suggesting the need for a stricter control of these factors and highlighting areas for further research.
Background: Despite its proven effectiveness and safety profile, XEN gel stents (Allergan Plc, Dublin, Ireland) can become obstructed. The causes and predicting factors for such obstructions still require further research. While hyphema has long been known to be responsible for secondary glaucoma through trabecular obstruction, it has not been associated, to date, with XEN gel stent obstruction.
Case description: We describe the case of a 55-year-old female patient with primary open-angle glaucoma (POAG) who underwent bilateral XEN gel surgery. Her left eye developed a 2 mm postoperative hyphema, which resolved spontaneously within 8 days. Intraocular pressure (IOP) normalized at 12 mm Hg and increased to 50 mm Hg after 1 month in an otherwise normal-looking eye. Intraoperative examination revealed a nonfunctioning XEN gel stent, which was replaced and sent for laboratory analysis. Macroscopic examination of the tube confirmed obstruction with cellular debris. Tube replacement restored good filtration.
Conclusion: This case report confirms cellular debris as a potential cause of XEN gel stent occlusion, suggesting that aqueous red blood cells (RBCs) could potentially pose a threat to the microstents’ patency even in cases when the bleeding was minimal and self-limited and where the IOP was still controlled at the time of full hyphema resolution. This observation could lead to recommendations for a stricter control of bleeding risk factors prior to microinvasive glaucoma surgery (MIGS), and it raises the question of whether anterior chamber (AC) washout should be advised in postoperative hyphema.
Clinical significance: This case highlights some previously unreported risk factors for XEN stent obstruction and suggests that stricter control of bleeding and monitoring of patients following hyphema could improve surgical outcome.
Del Valle-Nava Fernando,
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Fernando DV, GF D, Alfonso G, Francisco O. Management of Persistent Hypotony after Supraciliary CyPass® Implantation Using Argon Laser. J Curr Glaucoma Pract 2019; 13 (3):116-118.
Purpose: To report a case and management of persistent hypotony with hypotony-induced maculopathy after CyPass® device implant.
Background: The CyPass® was the first supraciliary ab interno device approved by FDA and commercially available. Efficacy studies showed adequate intraocular pressure (IOP)-lowering results in combination with phacoemulsification. Hypotony induced by suprachoroidal minimally invasive glaucoma surgery (MIGS) was reported to be lower than 3% in the population that comprised the COMPASS study.
Case description: A 57-year-old female patient with mild open-angle glaucoma with maximum topical medical therapy who underwent sequential bilateral CyPass® implantation developed persistent hypotony. Device obstruction was induced through argon laser burns directed to the peripheral iris, and the device was no longer visible on follow-up examinations. Topical IOP-lowering medication was restarted (timolol–dorzolamide) and has since been controlled under 16 mm Hg, without progression on visual fields.
Conclusion: Argon laser burns directed to the peripheral iris to induce synechiae development that produces device obstruction are an effective technique to manage persistent hypotony after supraciliary CyPass® implantation.
Clinical significance: Here, authors show a novel approach for treatment of persistent hypotony secondary to CyPass® implantation. In the knowledge of the authors, this is the first report that describes a noninvasive management for this complication, and this case could help other physicians to manage similar cases.