The efficacy of adjunctive mitomycin C and/or anti-VEGF agents on glaucoma tube shunt drainage device surgeries: a systematic review.

PURPOSE: The effectiveness of mitomycin C (MMC) in trabeculectomy has long been established. The aim of this review is to evaluate the efficacy and safety of adjunctive agents in tube shunt drainage device surgery for glaucoma or ocular hypertension, since controversy still exists regarding their benefit. METHODS: We searched CENTRAL, PubMed, Embase, Web of Science, Scopus, and BASE for RCTs, which have used adjuvant antimetabolites-either MMC or 5-Fluorouracil (5-FU)-and/or anti-vascular endothelial growth factors (anti-VEGF) agents. The main outcome was IOP reduction at 12 months. RESULTS: Ten studies met our inclusion criteria. Nine used the Ahmed Glaucoma Valve (AGV) implant, while the double-plate Molteno implant was used in one study. Four studies used MMC. The remaining six studies used an anti-VEGF drug - either bevacizumab, ranibizumab or conbercept. Only one MMC-study reported a significant difference in the IOP reduction between groups at 12 months, favouring the MMC group (55% and 51%; p < 0.01). A significant difference was also reported by two out of five bevacizumab-studies, both favouring the bevacizumab group (55% and 51%, p < 0.05; 58% and 27%, p < 0.05), with the highest benefit seen in neovascular glaucoma cases, especially when panretinal photocoagulation (PRP) was also used. Neither ranibizumab nor conbercept were found to produce significant differences between groups regarding IOP reduction. CONCLUSION: There is no high-quality evidence to support the use of MMC in tube shunt surgery. As for anti-VEGF agents, specifically bevacizumab, significant benefit seems to exist in neovascular glaucoma patients, especially if combined with PRP.

Comparison of the 1-year postoperative results of phacoemulsification-trabeculectomy and phacoemulsification-ExPRESS miniature shunt combined surgeries.

BACKGROUND AND OBJECTIVE: This study aimed to compare the 1-year postoperative phacoemulsification-trabeculectomy (P-Trab) and phacoemulsification-ExPRESS® (P-200 model) miniature shunt (P-ExPRESS) combined surgeries. MATERIALS AND METHODS: This retrospective, comparative clinical study investigated 41 eyes of 41 patients diagnosed with open-angle glaucoma and cataract. Of these, 21 eyes underwent P-Trab surgery and 20 eyes underwent P-ExPRESS surgery. The 1-year follow-up results, including intraocular pressure (IOP), visual acuity (VA), medications, and complications, were reviewed and compared. A 5 ≤ IOP ≤ 18 mmHg or 30% reduction from baseline was defined as Qualified Success (QS-1), and target IOP without medication was defined as Complete Success (CS-1). A 5 ≤ IOP ≤ 15 mmHg or 40% reduction from baseline was defined as Qualified Success (QS-2), and target IOP without medication was defined as Complete Success (CS-2). RESULTS: The mean follow-up time was 16 months (12-26 months). Results after the twelfth month for P-Trab versus P-ExPRESS are: CS-1: 42.8% versus 60.0% (P = 0.354); QS-1: 86.7% versus 95% (P = 0.606); CS-2:33.3% versus 40% (P = 0.751); QS-2: 66.6% versus 75% (P = 0.733). Kaplan-Meier survival analysis was not statistically significant between two groups for both QS-1, CS-1 and QS-2, CS-2 (P = 0.329 vs P = 0.365, P = 0.765 vs P = 0.789, respectively). Pre-op mean IOP was: 33.19 ± 8.7 versus 34.55 ± 11.3 mmHg; post-op mean IOP was: 15.19 ± 3.07 versus 15.30 ± 3.32 mmHg (P = 0.913); pre-op mean VA was: 1.17 ± 1.04 versus 1.15 ± 1.07 logMAR; and post-op mean VA was: 0.61 ± 0.80 versus 0.66 ± 0.99 logMAR (P = 0.869). The pre-op mean number of antiglaucomatous medications was 3.76 ± 0.53 versus 3.30 ± 1.45, and the post-op results were 1.52 ± 1.53 versus 0.85 ± 1.26 (P = 0.135). Comparing the pre-op and post-op values, both types of surgeries were equally effective (P = 0.00). Surgical failure was 14.2% (3/21) versus 5% (1/20), and the incidence ratios of significant complications were: 47% (10/21) versus 10% (2/20) and P-Trab versus P-ExPRESS, respectively (P = 0.015). CONCLUSION: The 1-year postoperative results suggest that P-ExPRESS is as effective as P-Trab, with fewer complications.

Effect of mitomycin c and 5-flurouracil adjuvant therapy on the outcomes of Ahmed glaucoma valve implantation.

BACKGROUND: To examine the effect of mitomycin c and 5-flurouracil on treatment outcomes following Ahmed glaucoma valve implantation. DESIGN: Retrospective consecutive case series. PARTICIPANTS: Fifty patients who received Ahmed glaucoma valve implantation from 1999 to 2013 in the San Francisco Veterans Administration Hospital. METHODS: The +INJECTION group received intraoperative mitomycin c followed by postoperative mitomycin c and/or 5-flurouracil, whereas the -INJECTION group did not. MAIN OUTCOME MEASURES: Primary outcome was treatment success at 1 year post-implantation. Intraocular pressure, hypertensive phase, and the number of glaucoma medications were also examined. RESULTS: Twenty-six patients/eyes in the +INJECTION group and 24 patients/eyes in the -INJECTION group were included. Treatment success was higher in the +INJECTION compared with the -INJECTION group (86 vs. 58%; P = 0.04). Intraocular pressure was lower in the +INJECTION compared with the -INJECTION group at 1, 3, 6 and 12 months (P ≪ 0.00001, P = 0.00003, 0.0008 and 0.024). Hypertensive phase occurred less often in the +INJECTION compared with the -INJECTION group (3.8 vs. 54%; P = 0.021). The +INJECTION group required fewer medications compared with the -INJECTION group (P = 0.02, 0.002, 0.003 and 0.008 at 1, 3, 6 and 12 months). Complication rates were comparable between groups (46.2 and 54.2%; P = 0.63). CONCLUSIONS: Adjuvant treatment with antifibrotics following Ahmed glaucoma valve implantation decreased the hypertensive phase and improved surgical outcomes without impacting complication rates at 1 year. This study postulates a role for antifibrotics in the postoperative management of Ahmed glaucoma valves.

Glaucoma Surgery in Pregnancy: A Case Series and Literature Review.

Glaucoma management in pregnant patients is a real challenge, especially when the glaucoma is not controlled with medications. We report the results of 6 incisional glaucoma surgeries for the management of medically uncontrolled glaucoma patients during pregnancy. This retrospective, case series was conducted on the 6 eyes of 3pregnant patients with uncontrolled glaucoma using maximum tolerable medications. Details of the glaucoma surgical management of these patients as well as their postoperative care and pregnancy and clinical outcomes on longitudinal follow-up are discussed. All 3 patients had juvenile open-angle glaucoma and were on various anti-glaucoma medications, including oral acetazolamide. The first case described underwent trabeculectomy without antimetabolites in both eyes because of uncontrolled intraocular pressure with topical medications. The surgery was done with topical lidocaine jelly and subconjunctival lidocaine during the second and third trimesters. The second patient had an Ahmed valve implantation in both eyes during the second and third trimesters because of uncontrolled IOP with topical medications and no response to selective laser trabeculoplasty. Surgery was done with topical tetracaine and subconjunctival and sub-Tenon's lidocaine. The third case had a Baerveldt valve implantation under general anesthesia in the second trimester. In selected pregnant glaucoma patients with medically uncontrolled intraocular pressure threatening vision, incisional surgery may lead to good outcomes for the patient with no risk for the fetus.

Novel Biomaterials in Glaucoma Treatment.

Glaucoma is a significant cause of blindness worldwide, and its treatment remains challenging. The disease progressively leads to damage to the optic disc and thus loss of visual acuity and visual field. High intraocular pressure (IOP) is a common risk factor. There are three major methods to treat this disease: topical, laser, and surgical. None of these are completely satisfactory; therefore, alternatives using new biomaterials are being sought. Since biomaterial engineering has experienced significant growth in recent decades, its products are gradually being introduced to various branches of medicine, with the exception of ophthalmology. Biomaterials, such as glaucoma drainage implants, have been successfully used to treat glaucoma. There is significant ongoing research on biomaterials as drug delivery systems that could overcome the disadvantages of topical glaucoma treatment, such as poor intraocular penetration or frequent drug administration. This article summarizes the use of novel biomaterials for glaucoma treatment presented in the literature. The literature search was based on articles published in English on PubMed.gov, Cochranelibrary.com, and Scopus.com between 2018 and 2023 using the following term "biomaterials in glaucoma." A total of 103 published articles, including twenty-two reviews, were included. Fifty-nine articles were excluded on the basis of their titles and abstracts.

Long-term results of Ahmed glaucoma valve implantation with/without intravitreal anti-VEGF injection in neovascular glaucoma patients.

PURPOSE: This study aimed to evaluate the efficacy of Ahmed glaucoma valve (AGV) implantation with or without anti-VEGF injections in neovascular glaucoma patients. MATERIALS AND METHODS: This single-center retrospective study assessed NVG patients who underwent AGV implantation with or without anti-VEGF injections. Demographic and clinical data, including ocular findings, intraocular pressure (IOP), visual acuity, and glaucoma medication count, were recorded preoperatively and postoperatively at one day, one month, and one year. The study included 35 patients. Group 1 consisted of 23 patients who received anti-VEGF injections before AGV surgery. Group 2, with 12 patients, had no anti-VEGF injections prior to surgery. Successful surgery was defined as IOP values between 6 and 21mmHg. The primary outcome was a 30% or more reduction in IOP. RESULTS: The groups displayed no significant difference in their demographic or clinical profiles (P>0.05). The visual acuity before and one year after surgery did not differ significantly between the groups. However, IOP values significantly decreased by the end of the one-year follow-up for both groups. No significant differences were found between the groups regarding visual acuity, IOP, or the number of medications during the one-year follow-up (P>0.05). Success rates were 95.7% for Group 1 and 91.7% for Group 2. No significant difference in complications between the groups was observed (P>0.05). CONCLUSION: Anti-VEGF injections prior to AGV implantation did not significantly impact visual acuity, IOP values, or medication count during the one-year follow-up.

Effect of Phacoemulsification on Intraocular Pressure in Eyes with Functioning Tube Shunts.

Purpose: To evaluate the effect of phacoemulsification on intraocular pressure (IOP) in eyes with functioning tube shunts. Methods: This was a retrospective chart review of primary open-angle glaucoma (POAG) patients with a functioning tube who underwent phacoemulsification and had ≥24 months of follow-up. The primary end point was defined as surgical failure (IOP > 21 mmHg) at month 24, progression to no light perception (NLP) vision, glaucoma reoperation, or implant removal. Surgical failure defined as IOP >18 and >15 mmHg, changes in visual acuity (VA), IOP, and number of medications were assessed. Results: Twenty-seven eyes of 27 patients with moderate or severe POAG were included. The mean age of the patients was 64.2 ± 10.8 years. The interval between the tube shunt and phacoemulsification was 28.8 ± 25.0 months. At the end of the study, four (14.8%) eyes met the failure criteria; the average time to failure was 9.3 ± 3.8 months. The causes of failure were high IOP in two (50.0%) and glaucoma reoperation in two (50.0%) eyes; however, no eyes progressed to NLP vision. Surgical failure defined as IOP >18 and >15 mmHg showed an increasing failure rate (18.5% and 48.5%, respectively).Themean IOP and medications number remained stable at month 24 compared to baseline (P = 0.131 and P = 0.302, respectively). Initially, VA showed improvement, with the greatest improvement at 6 months (P = 0.001), but at 24 months the improvement was no longer significant (P = 0.430). Conclusion: Phacoemulsification in patients with functioning tubes did not change the mean IOP in most of the patients (86.2%); the number of medications also did not increase.

Effect of Intraoperative Mitomycin C on the Surgical Outcomes of Ahmed Glaucoma Valve Implantation with Ciliary Sulcus Tube Placement.

PURPOSE: To evaluate the effect of intraoperative mitomycin C (MMC) on the surgical outcomes of ciliary sulcus (CS) Ahmed glaucoma valve (AGV) tube placement. METHODS: A retrospective review of medical records of 54 consecutive patients who underwent AGV implantation with tube placed in CS was performed. Consecutive cases operated without the use of intraoperative MMC from 2017 to 2019 were compared with consecutive cases operated with MMC from 2019 to 2021. Surgical failure was defined as intraocular pressure (IOP) exceeding 21 mmHg in two consecutive visits after postoperative 3 months or ≤30% IOP reduction, IOP ≤5 mmHg in two consecutive visits, or loss of light perception. Kaplan-Meier survival analysis and log-rank test were performed to compare the surgical failure rates. RESULTS: A total of 54 eyes of 54 patients were investigated. Mean follow-up period after AGV implantation was 1.4 ± 0.8 years. The MMC group showed significantly lower IOP during the 1st postoperative month (20.5 ± 8.6 mmHg vs. 15.8 ± 6.4 mmHg, p = 0.027), but the difference did not persist 6 months after the surgery (p = 0.805). The mean number of postoperative antiglaucoma medications was significantly lower in the MMC group in the 1st postoperative month (p = 0.047) but no difference was found at 6 months. No statistical difference was noted in the rates of postoperative complications. Kaplan-Meier survival analysis showed comparable survival rates between MMC group and no MMC group (p = 0.356). CONCLUSIONS: The intraoperative use of MMC significantly lowered IOP in the 1st postoperative month but did not increase 6 months success rates in patients receiving AGV tube placement in CS.

Race and Gender Shift among Academic Glaucoma Specialists in the Last 5 Decades.

Purpose: To evaluate the demographic composition of academic glaucoma specialists currently practicing in the United States. Design: Retrospective and observational study. Subjects: Academic glaucoma specialists identified from ophthalmology residency programs listed on the Doximity database. Methods: The American Board of Ophthalmology (ABO) membership directory, Doximity database, publicly available data, and direct communications were used to identify academic glaucoma specialists and their demographics. Information collected included-name, gender, race/ethnicity, geographic location, board certification date, academic affiliation, and academic rank. Ophthalmic age was defined as the number of years since ophthalmology board certification. Underrepresented minority (URM) groups were defined as Hispanics, Black or African Americans, Latinos, American Indians, or Alaskan Natives as defined by San Francisco match. In addition, the temporal, geographic, and academic rank distributions among females and URMs were explored. Main outcome measures: Women and URMs representations among academic glaucoma specialists across academic ranks, geographic regions, as well as ophthalmic age. Results: There were 457 active academic glaucoma specialists identified from 110 institutions in 38 states. Among them, 185 (40.5%) were women and 42 (9.2%) were URM. The proportion of women glaucoma specialists in academia had increased significantly with a rate of 1.049 in odds ratio (OR) per year (p < 0.001). However, there were no significant changes in the proportion of URMs over time. The earliest year of certification was 1,964 for males and 1,974 for females. When controlled for ophthalmic age, there were no significant differences in the distribution of women or URMs between the different academic ranks (p = 0.572 and p = 0.762, respectively). Among assistant professors, women had a significantly higher ophthalmic age compared to men (p < 0.001), but there was no significant difference in ophthalmic age in both the associate and full professor groups. There were no significant differences in the geographic distribution of gender (p = 0.516) and URM across United States regions (p = 0.238). Conclusion: The proportion of women among academic glaucoma specialists has significantly increased over the past 5 decades; however, the proportion of URMs has been stagnant in the same period. Enhancing URM representation among academic glaucoma specialists deserves to be a future priority. How to cite this article: Afzali K, Fujimoto DK, Mohammadi SO, et al. Race and Gender Shift among Academic Glaucoma Specialists in the Last 5 Decades. J Curr Glaucoma Pract 2023;17(2):98-103.

New Devices in Glaucoma.

Glaucoma remains a leading cause of blindness globally. Minimally invasive treatment techniques are rapidly expanding the availability of therapeutic options for glaucoma. These include devices aimed at enhancing outflow through the subconjunctival space, Schlemm's canal, and suprachoroidal space, sustained-release drug delivery devices, and extraocular devices aiming to reduce glaucomatous progression through other novel means. In this review, we provide an overview of several novel devices either newly available or in development for the medical and surgical management of glaucoma. Further studies are required to determine the long-term efficacy of these devices and how they will integrate into the current landscape of glaucoma management.

Surgical advancement in glaucoma during the past 10 years.

Recent years have seen a trend towards change in glaucoma treatment. In addition to classic trabeculectomy, implant surgeries such as those based on the Baerveldt, Ahmed and Molteno devices are increasingly performed as a primary procedure. This is doubtless partly due to the fact that surgeons have become more comfortable with the use of tube shunts and their postoperative management. The aim of this article is to present the currently available evidence on glaucoma surgery in a succinct format, to enable the best possible decisions to be made for patients.

Survival in Patients with Neovascular Glaucoma Following Tube Shunt Implant or Cyclodestructive Procedure.

Purpose: The study purpose was to assess patient survival after tube shunt implant or cyclodestructive procedure for neovascular glaucoma and to determine whether specific preoperative factors are predictive of survival. Materials and methods: A retrospective chart review was performed on patients with neovascular glaucoma who underwent tube shunt implant and/or cyclodestructive procedure between January 2002 and December 2019 at the Minneapolis Veterans Affairs Health Care System. Patient survival was compared to the age and gender-matched Minnesota population. Cox regression analyses were performed to evaluate preoperative parameters and survival. Results: Tube shunt alone was implanted in 30 eyes, cyclodestruction alone was performed in nine eyes, and two eyes underwent both (n = 41 eyes, 39 patients). The postoperative 5-year survival rate was 62% in neovascular glaucoma patients compared to 80% in controls. Survival did not differ significantly based on neovascular glaucoma etiology. Preoperative best-corrected visual acuity of the neovascular glaucoma-affected eye (p = 0.05) and Charlson Comorbidity Index (p = 0.02) were associated with survival, but preoperative maximum intraocular pressure, hemoglobin A1c, and creatinine were not. The mean intraocular pressure at 6 months postprocedure was 14 mm Hg for tube shunt and 27 mm Hg for cyclodestruction (p = 0.03). Conclusion: Neovascular glaucoma patients have reduced survival, but the majority survived at least 5-year postprocedure. Ophthalmologists should consider patient survival and factors predictive of survival when planning procedures for neovascular glaucoma. Clinical significance: Our findings provide an updated perspective on survival in the setting of neovascular glaucoma and can help ophthalmologists provide patient-centered and holistic care. How to cite this article: Zhou Y, Coleman S, Boysen J, et al. Survival in Patients with Neovascular Glaucoma Following Tube Shunt Implant or Cyclodestructive Procedure. J Curr Glaucoma Pract 2022;16(2):74-78.

A new glaucoma drainage implant with the use of Polytetrafluoroethylene (PTFE). A pilot study.

Purpose: To investigate the implantation of Polytetrafluoroethylene (PTFE) as a glaucoma drainage device. Methods: This study has been done in two steps. First, the constructed implants have been used in 4 rabbits and the histopathologic response was evaluated. In the second step, the implants were used in the 6 eyes of 6 patients with end-stage glaucoma with uncontrolled IOP and poor visual acuity. The tube was made of two-layer of PTFE membrane measuring 8 * 6 mm with a thickness of 1.8 mm and a silicone tube. The rabbits and the human eyes underwent surgical implantation of the tube in the anterior chamber. The histopathologic evaluation was done using H&E staining. Visual acuity, intraocular pressure and the number of glaucoma medications were assessed before and after the surgery. Results: In the histopathologic evaluation, subconjunctival polarizing fibers of a synthetic mesh infiltrated by fibrovascular septa was seen. A granulomatous inflammatory reaction composed of histiocytes, lymphocytes, and multinucleated giant cells were seen around and between the synthetic bundles. The average age of patients was 63 ± 5.5 years. The mean IOP reached from 36.6 ± 5.7 mmHg at baseline to 16.2 ± 8.9 mmHg at the final follow-up. Patients were followed for an average of 6.6 ± 4.5 months. One patient found hypotony refractory to medical and surgical treatment, which led to implant removal. One patient had uncontrolled IOP and finally led to phthisis bulbi following slow CPC. The remaining four eyes did well during the follow-up. Conclusion: The use of PTFE as a new polymer in tube shunt construction was reported. Larger studies, modification of the PTFE membranes like changing the porosity amount, and size of PTFE membranes might result in different conclusions.

Risk Factors for Failure in Double-Plate Tube Surgery for Refractory Glaucoma: 25 Years Surgical Experience.

PURPOSE: To investigate risk factors associated with success and failure in double-plate tube surgery. METHODS: This retrospective case-series observational study included 243 consecutive eyes that underwent anterior-segment double-plate tube surgery from 1990 to 2015. Evaluation of the efficacy of the device was based on the final intraocular pressure (IOP) and the need for anti-glaucoma medication. We also assessed success and failure according to risk factors for trabeculectomy and an early hypertensive phase (HP). RESULTS: Preoperative IOP was 37.3±13.1 mmHg (mean±SD) with 3.0±0.7 medications. After a median follow-up of 44.3 months, the mean IOP was 14.6±6.3 mmHg with 0.4±1.0 medications. The final IOPs ranged from 6 to 21 mmHg in 87.24% of eyes; however, 25.47% required medication. No risk factors studied were associated with surgical failure. Preoperative IOP, glaucoma type, previous surgery, previous anti-glaucoma drugs, implant type, and HP were associated with partial success (p<0.05). HP and preoperative use of brimonidine reduced the probability of complete success by 66.9% and 68.2%, respectively (p<0.05). HP was more likely when chronic preoperative prostaglandin analogues were administered (odds ratio [OR] 4.286; 95% confidence intervals [CI] 1.593-11.529; P=0.0039) and when the tube was located in the posterior chamber (OR 3.561; 95% CI 1.286-9.861; P=0.0145). CONCLUSION: Tube surgery is effective and seems to be independent of the major risk factors for glaucoma surgery. However, previous surgery and some chronic preoperative drugs are related to the need for glaucoma medication to achieve the target pressure.

Tube-in-tube: A Solution for Retracted Tube.

Tube retraction after Ahmed glaucoma valve (AGV) implantation is an infrequent but known complication. The management option includes the use of a commercially available AGV tube extender, 22 G angiocatheter, resisting the existing glaucoma drainage device (GDD), or insertion of a new GDD. Each of the methods described in the literature has its limitations. We describe the successful management of this complication by using a cost-effective technique of connecting the silicone tube segment to the existing tube to lengthen the tube, so that it could be inserted in the anterior chamber again. The silicone tubes used for the technique were the extra length of the GDD tube, which was cut short and leftover during other GDD implantation surgeries. CLINICAL SIGNIFICANCE: During any GDD implantation, the tube is cut short before entering the anterior chamber. We retrieved the short segments of the tube immediately after the GDD was opened on the table and sterilized them again using plasma technology, available in our operating room. Hence, it provides a cost-effective alternative since the tube is usually trimmed to the desired length in all cases of GDD implantation (valved/non-valved), which can be subsequently sterilized and reused for lengthening the short tube in cases with tube retraction or inadvertently cut tube. HOW TO CITE THIS ARTICLE: Pandav SS, Gautam N, Thattaruthody F. Tube-in-tube: A Solution for Retracted Tube. J Curr Glaucoma Pract 2021;15(1):44-46.

Comparison of surgical outcomes between sulcus and anterior chamber implanted glaucoma drainage devices.

PURPOSE: This retrospective case-control cross-sectional study compared the outcomes of sulcus placement of glaucoma drainage devices (GDD) versus traditional anterior chamber (AC) to test the hypothesis that sulcus placement results in fewer complications whilst maintaining similar efficacy. METHODS: This study included 45 patients in the sulcus group and 60 patients in the anterior chamber (AC) group who had undergone surgery from January 2014 to December 2017. Data were collected on pre-operative demographics, operative details and post-operative intraocular pressure and complications. The IOP, number of medications and complications between the two groups was compared. A P value of <5% was considered statistically significant. RESULTS: The sulcus group had significantly lower overall complications compared to the AC group with a comparable IOP decrease between groups. There were significantly lower rates of hyphaema in the sulcus (3 cases) compared to AC group (17 cases) (P < 0.05). Severe or late complications (implant exposure, corneal decompensation, endophthalmitis, poor vision, choroidal hemorrhage and cornea edema) were significantly lower in the sulcus group [2 eyes; 4.4%] compared to the AC group [13 eyes; 21.7%] (P < 0.05). The sulcus group required fewer medications during the follow-up period. CONCLUSION: Sulcus implantation of GDD resulted in less postoperative hyphaema and severe complications compared to AC implantation. Our findings concur with the literature that sulcus implantation is safe and effective for controlling IOP for various types of glaucoma. The long-term effects of endothelial cell loss for sulcus versus AC implantation require further evaluation.

Effect of Head Position and Tube Entry on Corneal Endothelial Cells in Patients with Glaucoma Drainage Implants: A Cross-sectional Study.

PURPOSE: To investigate the effect of head tilt on the tube position of the Ahmed glaucoma valve (AGV) implanted in patients with glaucoma and to assess how the head tilt-induced alterations of tube parameters and the level of tube entry influence corneal endothelial cell density (ECD). METHODS: A total of 29 eyes of 26 patients with AGV implantation were included. Tube-cornea distance, tube-cornea angle, and intracameral tube length were measured using anterior segment optical coherence tomography in three different head positions (neutral, 30° temporalward tilt, and 30° nasalward tilt). The tube entry was assessed using static gonioscopy. ECD was measured using specular microscopy before and after surgery. RESULTS: The mean tube-cornea distance, tube-cornea angle, and intracameral tube length (neutral: 0.87 ± 0.39 mm, 30.56 ± 5.89˚, and 3.10 ± 0.82 mm, respectively) decreased with head tilts (temporalward: 0.82 ± 0.39 mm, 29.27 ± 5.82˚, and 3.04 ± 0.82 mm, respectively; nasalward: 0.83 ± 0.40 mm, 29.61 ± 6.04˚, and 3.05 ± 0.81 mm, respectively; all p < 0.01). The multivariate analyses found age and the tube insertion level to be associated with postoperative changes in the central ECD (p = 0.039 and 0.013, respectively), and the postoperative follow-up period and tube insertion level to be associated with the difference between the inferonasal and superotemporal ECDs (p = 0.034 and 0.007, respectively). CONCLUSIONS: Mild alterations of head positions induced changes in the intracameral tube positions of AGV implants; nevertheless, it did not significantly affect ECD loss. However, the eyes with tubes inserted anteriorly to Schwalbe's line may be more susceptible to corneal ECD loss.

Effective treatment of a normal-tension glaucoma patient with bilateral ab externo XEN Gel Stent implantation.

PURPOSE: To provide the first report of effective use of bilateral XEN Gel Stent implantation using an ab externo open-conjunctival approach designed to improve bleb function and meet the uniquely low intraocular pressure requirements of a Japanese patient with normal-tension glaucoma refractory to topical medical therapy. OBSERVATIONS: A 54-year-old phakic Japanese woman with severe normal-tension glaucoma on maximally tolerated medical therapy of four topical agents presented with above-goal intraocular pressures and new medication intolerances. She underwent bilateral ab externo open-conjunctival XEN Gel Stent implantation with tenectomy and sub-Tenon's injection of 40µg of mitomycin-C, which resulted in reduction of intraocular pressures by 41.2 and 28.6% to 10 and 10 mmHg in the right and left eyes, respectively at the most recent visit. Postoperatively, a diffuse filtering bleb with good morphology developed in both eyes. The procedure has so far allowed for complete cessation of all four topical medications for up to eight months following surgery without any serious complications. CONCLUSIONS: This case illustrates the potential of Xen Gel Stent implantation through an ab externo, open-conjunctival approach to be an effective, simple alternative to trabeculectomy to meet the unique low-pressure requirements of normal-tension glaucoma patients with practical and safety benefits of a micro-invasive approach.

Update in Genetics and Surgical Management of Primary Congenital Glaucoma

Primary congenital glaucoma (PCG) continues to be an important cause of visual impairment in children despite advances in medical and surgical treatment options. The progressive and blinding nature of the disease, together with the long lifespan of the affected population, necessitates a thorough understanding of the pathophysiology of PCG and the development of long-lasting treatment options. The first part of this review discusses the genetic features and makeup of this disorder, including all currently identified genetic loci (GLC3A, GLC3B, GLC3C and GLC3D) and relevant protein targets important for trabecular and Schlemm canal dysgenesis. These target molecules primarily include CYP1B1, LTBP2, and TEK/Tie2 proteins. Their potential roles in PCG pathogenesis are discussed with the purpose of bringing the readers up to date on the molecular genetics aspect of this disorder. Special emphasis is placed on functional implications of reported genetic mutations in the setting of PCG. The second part of the review focuses on various modifications and refinements to the traditional surgical approaches performed to treat PCG, including advances in goniotomy and trabeculotomy ab externo techniques, glaucoma drainage implant surgery and cyclodiode photocoagulation techniques that ultimately provide safer surgical approaches and more effective intraocular pressure control in the 21st century.

Evaluation of early ocular discomfort after glaucoma surgery: trabeculectomy versus Ahmed glaucoma valve implantation

ABSTRACT Purpose: This study aims to compare the initial ocular discomfort symptoms resulting from trabeculectomy and Ahmed glaucoma valve implantation surgeries. Methods: A prospective comparative study was conducted. The evaluation of ocular discomfort employed a questionnaire designed to identify the frequency and severity of distinct symptoms: ocular pain, general discomfort, tearing, foreign body sensation, and burning. This questionnaire was administered prior to surgery as a baseline, and subsequently at 7, 30, and 90 days post-surgery. Simultaneously, the Ocular Surface Disease Index (OSDI) was applied at these same time intervals. Results: The study encompassed a total of 17 patients (9 undergoing trabeculectomy and 8 undergoing Ahmed glaucoma valve implantation). The Ahmed glaucoma valve implantation group exhibited higher tearing levels at baseline (p=0.038). However, no statistically significant differences in symptoms were observed between the two surgeries at 7 and 30 days post-surgery. At the 90-day mark following surgery, patients who had undergone trabeculectomy reported a significantly higher foreign body sensation (p=0.004). Although OSDI scores did not differ between groups at baseline, the trabeculectomy group showed significantly higher OSDI scores than the Ahmed glaucoma valve implantation group at 7, 30, and 90 days after surgery (p<0.05). Conclusion: Post-surgery, patients who had undergone trabeculectomy experienced increased foreign body sensation. Trabeculectomy appears to cause greater early postoperative ocular discomfort compared to the Ahmed glaucoma valve implantation group.