After Ahmed Glaucoma Valve Implantation Research Articles

Effect of Early Aqueous Suppression After Valved Tube Shunt Surgery for Uveitic Glaucoma

To compare outcomes of early aqueous suppression (EAS) and standard therapy (ST) after Ahmed Glaucoma Valve (AGV) implantation for uveitic glaucoma. Retrospective comparative cohort study. All patients with uveitic glaucoma underwent AGV implantation from January 2010 to October 2020 at Northwestern Medicine. Excluding the first postoperative day 1 (POD1), only eyes with IOP 10-15 mmHg at their first visit with IOP ≥ 10 mmHg were included in the main analysis. Early aqueous suppression (EAS) was defined as initiation of ocular hypotensive therapy when IOP was first 10-15 mmHg. Standard therapy was initiation of therapy at any later time. Failure was defined as IOP > 21 mmHg, < 5 mmHg, or < 20% reduction in IOP from baseline after 3 months, for 2 consecutive study visits. Hypotony was defined as IOP ≤ 5 mmHg for ≥ 2 visits. Hypertensive phase was defined as IOP > 21 mmHg for 2 consecutive visits in the first 3 months. Proportion achieving overall success; incidence of hypotony and hypertensive phase. Twenty-eight eyes of 26 patients were in the EAS group and 20 eyes of 19 patients were in the ST group, with a mean follow-up of 17.7 and 28.2 months, respectively. Baseline IOP was similar in the EAS (31.2±10.1 mmHg) and ST (34.6±12.2 mmHg) groups; P=0.18. Final IOP was lower in the EAS group (12.9±4.6 mmHg) than the ST group (16.4±5.7 mmHg; P=0.02) on 2.6±0.9 medications in the EAS group and 1.8±1.5 in the ST group (P=0.07). Overall success was achieved in 87% of EAS eyes and 74% of ST eyes (P=0.43). There were no statistically significant differences in the occurrence of additional glaucoma surgery (4%for EAS, 20% for ST; P=0.11), hypotony (7% for EAS, 0% for ST; P=0.50), or hypertensive phase (4%forEAS, 21% for ST; P=0.09). EAS was associated with a lower final IOP after AGV in uveitic glaucoma eyes; however, more medications were in use at the final visit. No statistically significant differences in overall success or the incidence of adverse events were observed. Proprietary or commercial disclosure may be found in the Footnotes and Disclosures at the end of this article.

Long-Term Visual Field Outcomes After Ahmed Glaucoma Valve Implantation

To measure visual field (VF) rates of change after Ahmed Glaucoma Valve (AGV) implantation and to investigate risk factors for progression. Retrospective, clinical cohort study. Patients who underwent AGV implantation with at least 4 eligible postoperative VFs and 2 years of follow-up were included. Baseline, intraoperative, and postoperative data were collected. VF progression was explored with 3 methods: mean deviation (MD) rate; glaucoma rate index (GRI); and pointwise linear regression (PLR). For a subset of eyes with sufficient preoperative and postoperative VFs, rates were compared between the 2 periods. A total of 173 eyes were included. The intraocular pressure (IOP) and number of glaucoma medications were significantly reduced from a median (interquartile range [IQR]) of 23.5 (12.1) mm Hg at baseline to 12.8 (4.0) mm Hg at final follow-up, and from (mean ± SD) 3.3 ± 1.2 to 2.2 ± 1.4, respectively. A total of 38 eyes (22%) showed VF progression, and 101 eyes (58%) were stable as assessed by all 3 methods, which accounted for 80% of all eyes. The rate of VF decline by MD and GRI was a median (IQR) of -0.30 (0.8) dB/y and -2.30 (10.6) (of -100), respectively. When comparing progression before and after surgery, the reduction was not statistically significant with any of the methods. The peak IOP (after 3 postoperative months) was associated with VF deterioration, with a 7% increase in risk per each additional millimeter of mercury (mm Hg). To our knowledge, this is the largest published series reporting long-term VF outcomes after glaucoma drainage device implantation. There is a continued, significant rate of VF decline after AGV surgery.

Short-term outcomes of mitomycin C-augmented excisional bleb revision with capsulectomy for failed Ahmed glaucoma valve.

To report short-term outcomes of mitomycin C-augmented excisional bleb revision with capsulectomy (ERC) after Ahmed glaucoma valve (AGV) failure. Patients who underwent ERC procedures between January 2017 and December 2019 with a minimum follow-up of 6mo were evaluated retrospectively for indications of AGV and AGV implantation to ERC interval. The number of anti-glaucoma medications (AGMs), intraocular pressure (IOP) and best corrected visual acuity (BCVA) were recorded at baseline, 1, 7, 30, 90, and 180d. Intra- and postoperative complications were also recorded. Positive outcome was defined as IOP≤21 mm Hg with or without AGMs. Fourteen eyes [14 patients, median age 69.5y, interquartile range (IQR) 61.3-80] were included. Pseudoexfoliative glaucoma (n=5, 36%) was the most common form of glaucoma. The median AGV implantation to ERC interval was 8.8mo (IQR 3.91-43.67). At 6mo, the median number of AGMs decreased from 3.0 (IQR 3.0-4.0) to 2.0 (IQR 1.5-3), the median IOP decreased from 26 mm Hg (IQR 22-29) to 16.5 mm Hg (IQR 13.75-20) and there was no significant change in BCVA. The success rate at 6mo was 92.9%. The Kaplan-Meier cumulative probability of survival was 93%, 79%, 64%, and 64% at 1wk, and 1, 3, and 6mo, respectively. No intraoperative complications were identified. Postoperative complications were identified in 5 eyes (36%), which were resolved spontaneously during the first week following ERC. ERC has a high success rate for short-term management of AGV failure. A longer follow-up study is required to determine long-term cumulative failure rates.

Risk factors for hypertensive phase after Ahmed glaucoma valve implantation.

To investigate the risk factors and the clinical characteristics of the hypertensive phase (HP) after Ahmed glaucoma valve (AGV) implantation. This retrospective study included 60eyes of 57 patients who underwent AGV implantation and with at least 1-year follow-up. HP was defined as intraocular pressure (IOP) > 21mmHg in the first 3months after the surgery. Independent samples t-test and Chi-square test were used to compare differences in patients with the HP and the non-HP groups. Univariable and multivariable logistic regression analyses were used to determine the risk factors for the development of the HP. Statistical significance was assumed at p < 0.05 level. HP was observed in 31 eyes (51.7%) with an average peak IOP of 27.6 ± 4.5mmHg (range 22-40mmHg). The resolution of HP was noted in 27eyes (87.1%) at the 3rd month postoperative visit. The number of glaucoma medications at the last postoperative visit and IOP values from 1month to 1year were significantly higher in the HP group (all p < 0.05). Patients with traumatic glaucoma showed the highest rate (83.3%) of HP development. In the multivariable analysis, a preoperative IOP > 30mmHg (p = 0.03, OR:5.82; reference: ≤ 25mmHg) and younger age (41-64years, p = 0.02, OR:8.49; ≤ 40years, p = 0.001, OR:19.62; reference: ≥ 65years) were independently associated with the occurrence of HP. Hypertensive phase was observed in half of the patients undergoing AGV implantation. A higher mean preoperative IOP and younger age were risk factors for HP development. Although the majority resolved at the 3-month visit, eyes with HP had higher mean IOPs and required more IOP lowering medications.

Transscleral Cyclophotocoagulation in Familial Amyloidotic Polyneuropathy Secondary Glaucoma after Ahmed Valve Implantation: A Case Series Study.

PurposeTo investigate the outcomes of transscleral cyclophotocoagulation (TSCPC) after Ahmed glaucoma valve (AGV) implantation failure in patients with familial amyloidotic polyneuropathy (FAP) secondary glaucoma.Materials and methodsIn this retrospective study, all patients with secondary FAP glaucoma who underwent AGV implantation between 2010 and 2019 in our tertiary center were assessed. Among all, those patients who needed TSCPC to control intraocular pressure (IOP) after AGV were selected. Demographic data, value of IOP, best-corrected visual acuity (BCVA), number of antiglaucomatous medications, surgical complications, and need for retreatment were collected.ResultsFrom a total of 124 eyes submitted to AGV implantation, 13 eyes (10.48%) needed TSCPC to control IOP. The median age at TSCPC was 49.50 years (43; 55.75), and the median period between AGV implantation and TSCPC was 1.63 years (1.00; 3.65). There was a significant decrease of IOP after the procedure, from 24.33 ± 4.76 to 11.33 ± 2.90 mm Hg at last visit (p < 0.001). A reduction in the number of antiglaucomatous medications was also noticed, from 3.92 ± 0.29 to 1.25 ± 1.42 (p < 0.001). There was no difference in BCVA (p = 0.502). After the procedure, there was an exuberant anterior chamber (AC) reaction in two eyes (16.7%), and one case developed a neurotrophic ulcer (8.3%). There was no need for re-treatment.ConclusionAhmed glaucoma valve implantation is a promising surgical procedure to treat patients with PAF secondary glaucoma, showing good results. For refractory cases, TSCPC seems to be effective and safe to control IOP.Clinical significanceThere are only a few studies in current literature that address amyloid secondary glaucoma, maybe because it is a rare pathology worldwide. However, it has a high incidence in certain regions, including the north of Portugal. For the record, this is the first study describing the tool of cycloablative procedures in this type of glaucoma.How to cite this articleVieira R, Marta A, Figueiredo A, et al. Transscleral Cyclophotocoagulation in Familial Amyloidotic Polyneuropathy Secondary Glaucoma after Ahmed Valve Implantation: A Case Series Study. J Curr Glaucoma Pract 2021;15(1):32–35.

Non-intraocular pressure-related revision surgeries after Ahmed glaucoma valve (AGV) implantation in refractory glaucoma.

Ahmed glaucoma valve (AGV) is an effective treatment method for refractory glaucoma (RG), however, additional surgical interventions may be required over the course of follow-up due to complications. Our aim is to investigate the causes, types, and outcomes of revisional surgical interventions apart from revisions aiming IOP control, following AGV implantation in patients with RG. The pre- and postoperative month 1-3-6-12 and last visit examination findings of the patients who underwent various surgical revisions of AGV between January 2015 and April 2018 in our clinic were recorded, as well as the interval between AGV implantation-revision surgery and the presence of any other complications necessitating additional surgery. The success criteria were defined on the basis of need for additional procedures. Twenty-six eyes of 24 patients were included. The follow-up time and the interval between AGV implantation-surgical revisions were median 12 (6-92) and median 9.7 (1-72) months, respectively. The most common complication requiring revision was tube exposure in 15 (57.7%) followed by tube malposition in 11 (42.3%) eyes. Further interventions were required only in one eye with recurrent exposure. AGV implantation has early and late tube-related complications necessitating revisional surgical interventions; which makes it important to have extended follow-up period for patients with AGV implants. Revisional interventions for AGV implants with tube-related complications are efficient procedures for the majority of patients, but recurrence may occur requiring additional revisions.

Ahmed implant coated with poly(2-methacryloyloxyethyl phosphorylcholine) inhibits foreign body reactions in rabbit eyes.

PurposeWound healing after Ahmed glaucoma valve (AGV) implantation often entails fibrosis as a foreign body reaction to the silicone plate. Poly(2-methacryloyloxyethyl phosphorylcholine) (PMPC) forms an antifouling surface that inhibits fibrosis during wound healing. In this study, we aimed to compare the effects of the implantation of AGV coated with PMPC (wPMPC) versus AGV without PMPC (woPMPC) in rabbits.MethodsSix New Zealand White rabbit does underwent AGV implantation in both eyes. For each rabbit, one eye was randomly selected for implantation of AGV wPMPC and a conventional AGV (woPMPC) was implanted in the contralateral eye. Gross conjunctival vascularity was compared between the two groups at the first, second, and fourth weeks after surgery. The eyes were enucleated in four weeks and subjected to staining with hematoxylin and eosin and Masson’s trichrome stain. The fibrosis and inflammation status among the eye samples were compared by measuring the thickness of the fibrotic walls and counting the number of chronic inflammatory cells around the AGV. Counting of inflammatory cells and measuring fibrotic wall thickness were done in a blinded method to eliminate observer bias. Statistical analysis was performed using the Mann-Whitney U test.ResultsGross and histological examinations revealed no toxic effects of PMPC. There were no apparent differences in overall conjunctival vascularity between the two groups at weeks 1, 2, and 4 after surgery. The average inflammatory cell counts were 14.3 ± 5.8 per slide and 27.3 ± 8.6 per slide in the wPMPC and woPMPC groups, respectively (p = 0.037). The average thicknesses of the fibrotic wall were 57.9 ± 11.3 μm and 81.5 ± 21.3 μm in the wPMPC and woPMPC groups, respectively (p = 0.025).ConclusionCompared to the woPMPC group, the number of inflammatory cells and fibrosis were significantly decreased in the wPMPC group.

Assessing risk factors for postoperative hypotony in Ahmed glaucoma valve implantation surgery.

To assess the risk factors associated with the development of hypotony after Ahmed glaucoma valve (AGV) implantation. One hundred and ninety-three eyes of 177 patients with various types of glaucoma that were treated with AGV implantation were retrospectively evaluated. Intraocular pressure lower than 6mmHg related to the surgery is defined as postoperative hypotony. Patients' demographic characteristics, type of glaucoma, preoperative and postoperative visual acuity, necessity of antiglaucoma treatments, lens status, previous ocular surgeries, intraocular pressure (IOP) measurements before and after surgeries, the need for additional procedures and postoperative complications were recorded from the patients' charts. Hypotony was seen in 68 of 193 eyes (35.2%) postoperatively. In 45 eyes (23.3%), it has occurred in first postoperative day and in 23 eyes (11.9%) after the first day within the first week. There was no difference in intraocular pressures between two groups in the first year follow-up. Pre- and postoperative best-corrected visual acuities, age and gender were not statistically different between hypotony and no hypotony groups (p > 0.05). Also, lens status, history of previous ocular surgery, type of glaucoma and number of preoperative glaucoma medication usage were not found to be different between groups (p > 0.05). Potential risk factors such as age, sex, lens status, history of previous ocular surgeries, preoperative glaucoma medication usage or glaucoma type are not found to influence upon postoperative hypotony prevalence for AGV surgery. Surgery type and personal ocular factors, which could not be determined beforehand, could be more important than demographic features.

Evaluation of Diplopia Secondary to Seton Implantation Surgery: Ahmed Glaucoma Valve and Diplopia

Objectives:To determine and evaluate the rate of diplopia after Ahmed glaucoma valve (AGV) implantation surgery.Materials and Methods:The records of patients who underwent AGV implantation in our hospital between the years of 2010 and 2017 were retrospectively reviewed. Patients who were referred to our strabismus department due to binocular diplopia after AGV implantation surgery were included. The details of postoperative day 1, day 7, day 15, and 1 month examinations were recorded. In the postoperative period, the onset time of diplopia complaints, diplopia type, and the presence of diplopia at distance and near fixation were noted. Ocular motility examination and deviation measurements were evaluated.Results:Ten (47%) of 211 patients who underwent AGV implantation in our hospital between 2010 and 2017 met the study inclusion criteria. Six of the 10 patients were men (60%) and 4 were women (40%). The mean age of the patients was 44.5 (34-63) years. Complaints of diplopia developed at a mean of 14.5±12.3 (1-30) days after AGV implantation. The prism measurements of the patients were found to be 8.4±1.4 prism diopters (PD) exotropia and 7.1±8.8 PD hypotropia. While 8 patients had diplopia only at near distance, 2 patients had diplopia at both distance and near. Three patients were treated with prismatic glasses, and their complaints of diplopia recovered spontaneously in 5.11±4.10 months. The other 7 patients were followed up without treatment, and their diplopia complaints resolved spontaneously in 6.11±4.40 months.Conclusion:Although most of the diplopia that develops after AGV implant surgery resolves without treatment, prismatic glasses might be considered as a treatment option in patients whose diplopia affects their daily lives.

The role of primary needle revision after Ahmed glaucoma valve (AGV) implantation.

To evaluate the efficacy and safety of primary needle revision after Ahmed Glaucoma Valve (AGV) implantation in comparison with glaucoma medication use. In this interventional case series, 23 eyes of 23 patients who underwent AGV implantation were enrolled. Needle revision was performed when the intraocular pressure was higher than the target pressure before glaucoma medications. Using a 30-gauge needle, the Tenon's capsule over the plate was incised and the bleb was reformed. Patients were examined on a postoperative day one, weekly (for four weeks), and every 1-3months. Two criteria were used to define cumulative success as a minimum 20% reduction in IOP and 5 <IOP ≤ 21mmHg (Criteria A) or 5 <IOP ≤ 18mmHg (Criteria B) without (Complete success) or with (Qualified success) glaucoma medication. In this pilot study, we enrolled 23 patients with a mean age of 53.8 ± 12.4years (25-78years) who underwent AGV implantation and a one-year follow-up period. The mean number of primary needle revision was 2.2 ± 1.6 (1-6). One year postoperatively, the cumulative success rate was 91.4% and 86.9% based on Criteria A and B, respectively. The average of preoperative IOP was 28.26 ± 8.86mmHg (range 15-46mmHg), reaching 13.78 ± 3.54mmHg (range 8-20) at the end of the one-year follow-up. (P < 0.001) The mean preoperative medication significantly decreased from a median of 4 (range 3-4) at baseline to 2 (range 1-4) after the one-year follow-up (P < 0.001). One patient experienced leakage over the plate, which was successfully treated via conservative management. This pilot study showed that primary needle revision is a safe and effective method for controlling IOP after AGV implantation with a lower need for medication.

Strabismus After Ahmed Glaucoma Valve Implantation

Most reports of strabismus after glaucoma drainage device implantation study larger devices and rarely note the incidence of strabismus after Ahmed glaucoma valve (AGV) implantation. It is unknown if the pattern of strabismus is similar with smaller devices. We investigated characteristics of strabismus after AGV implantation. Retrospective review. Institutional study of 732 patients at our institution undergoing AGV implantation between 2013 and 2018. Rate and characteristics of strabismus were the primary outcome; age, gender, and location of AGVs were also analyzed. We identified 29 patients who developed new-onset strabismus postoperatively after initial AGV implantation, for 4% incidence of strabismus. Twenty-one (72%) of these had diplopia. AGVs were implanted superotemporally in 21, superonasally in 5, inferotemporally in 1, and inferonasally in 2. Three patients were esotropic, 11 were exotropic, 4 had hypertropia, 2 had hypotropia, and 9 patients had combined horizontal/vertical strabismus (esotropia/hypotropia [n= 1] or exotropia/hypertropias [n= 8]). Exotropia was the most common type of strabismus in both the superotemporal and superonasal (60%) AGV groups. Superotemporal AGVs were more commonly associated with ipsilateral hypertropia (43%) than superonasal AGVs. Treatments included strabismus surgery (n= 14), prisms (n= 6), or an occlusive lens (n= 1). In the largest single-center series of patients undergoing initial AGV implantation, the overall incidence of postoperative strabismus was 4%. This is comparable to strabismus incidence following implantation of other types of glaucoma drainage devices, even larger devices. The possibility of this complication should be discussed with patients prior to surgery.

Relationship between Tube Parameters and Corneal Endothelial Cell Damage after Ahmed Glaucoma Valve Implantation: A Comparative Study.

Purpose: We compared the clinical factors, including anterior chamber tube parameters, in patients with and without corneal endothelial cell damage after Ahmed glaucoma valve (AGV) implantation. Methods: In this retrospective and comparative case series, patients who underwent AGV implantation were enrolled consecutively. Serial specular microscopy was performed before and after AGV implantation. Patients were divided into two groups depending on whether there was a significant decrease in corneal endothelial cell density (ECD), which was determined by each patient’s rate of ECD change (%/year), calculated using linear regression analyses. Tube parameters such as the tube-cornea distance (TCD) and tube-cornea angle (TCA) were measured with anterior segment optical coherence tomography. Clinical factors related to the rate of ECD change were evaluated with regression analyses and compared between the two groups. The tipping point at which tube parameters became significantly associated with the rate of ECD change was identified with broken stick regression analyses. Results: There were 30 eyes (32.3%) with ECD damage (group 1) and 63 eyes (67.7%) without damage (group 2). The mean rate of ECD change (%/year) was −18.82 ± 22.97 and 2.14 ± 2.93 in groups 1 and 2, respectively (p < 0.001). The TCA was the only clinical factor associated with the rate of ECD change (regression coefficient, β = 1.254, p < 0.001). The tipping point in the TCA was 26.70° (95% confidence interval, CI: 23.75–29.64°). The mean TCD (mm) was 0.98 ± 0.38 and 1.26 ± 0.39 (p = 0.002), and the mean TCA (degrees) was 28.67 ± 7.79 and 36.35 ± 5.35 (p < 0.001) in groups 1 and 2, respectively. Conclusions: A wider TCA was protectively associated with the rate of ECD change, and the TCA was significantly narrower in patients with ECD damage. When inserting a tube into the anterior chamber, surgeons should therefore try to secure a wide TCA of about 30°. In patients with a narrow TCA after AGV implantation, increased attention should be directed toward whether ECD decreases continuously.

Novel method of conjunctival revision for encapsulated blebs after ahmed valve implantation

Background: Encapsulation after Ahmed glaucoma valve (AGV) is difficult to manage and sometimes results in treatment failure. We proposed a novel conjunctival revision method to improve intraocular pressure (IOP) control due to encapsulation after AGV implantation. The efficacy and safety of this method in refractory glaucoma patients were evaluated. Methods: The present study was done in a clinical trial design. Patients of encapsulation after AGV implantation for at least 6 months were enrolled and divided into three groups (control group, single revision group, and repeated revision group). Characteristics such as visual acuity, glaucoma type, IOP change, underlying diabetes mellitus, and complications were assessed. Results: In total, 120 patients were enrolled in this study, and they were randomly divided into three groups on a 1:1:1 base. At the study end, there were 28 patients in the control group, 32 patients in single revision group and 37 patients in repeated revision group. The results showed that the conjunctival revision method significantly reduced the mean IOP of the encapsulated eyes on day 1 after the procedure (24.5 ± 6.3 to 11.8 ± 3.4 mmHg in single revision group and 25.1 ± 4.7 to 10.2 ± 2.3 mmHg in repeated revision group, respectively). The eye pressure was remained relatively low during follow-up visits for 4.17 ± 4.2 months in single revision group, whereas stable IOP could be maintained in repeated revision group for 10.43 ± 3.7 months in average. Changes in preoperative and postoperative visual acuities and the refraction errors were insignificant. Only mild complications occurred and most resolved without treatment. Conclusions: The conjunctival revision could relieve entrapped subconjunctival aqueous and therefore reduced IOP temporarily with single procedure, and IOP could be maintained with repeated procedures. This method is suggested to be a safe and simple alternative for refractory glaucoma patients developed encapsulation after AGV implantation.

Needling with 5-fluorouracil for encapsulated blebs after Ahmed glaucoma valve implantation

Objective: To evaluate the efficacy of 5-fluorouracil (5-FU) needling of encapsulated blebs (EBs) after Ahmed glaucoma valve (AGV) implantation in patients with medically uncontrolled secondary glaucoma.Methods: Thirty-eight eyes of 37 patients who underwent AGV implantation due to secondary glaucoma with EB were recruited in this retrospective non-randomized study. 5-FU needling (0.1 mL of 50 mg/mL) was performed for the restore of the aqueous outflow. Success after needling was defined as last intraocular pressure (IOP) ≤21 mmHg or ≥6 mmHg (with or without the use of antiglaucoma medication) without loss of light perception.Results: The mean follow-up time was 14.5 ± 8.5 (5–36) months after needling. The mean interval between the AGV implantation and the needling was 10.2 ± 7.5 (2–32) weeks. Patients were examined after needling at the 2nd hour, 1st week, 1st month, 3rd month, 6th month, and at the final visit. The success rates were 84.2%, 94.7%, 94.7%, 86.8%, 83.3%, and 71.1%, respectively. The Kaplan–Meier survival analysis revealed 96.4%, 77.4%, and 60.3% cumulative predictive success rates for the 6th, 12th, and 24th months, respectively. The mean IOP before needling was 28 ± 8.4 mmHg. At the final visit, the mean IOP was 18.1 ± 7.5 mmHg (p ≤ 0.001). Complications after needling included Seidel without hypotony (three eyes, 7.9%), hyphema (one eye, 2.6%), and decompression retinopathy (one eye, 2.6%). Neovascular glaucoma was the only factor that affected efficacy of treatment negatively (p = 0.003).Conclusions: Bleb needling with 5-FU seems to be a safe and effective method in patients with EB formation after AGV implantation in secondary glaucoma cases.

Ciliochoroidal detachment after Ahmed glaucoma valve implantation: a retrospective study

BackgroundTo investigate the occurrence of ciliochoroidal detachment (CCD), its risk factors and its impact on the success rate after Ahmed glaucoma valve (AGV) implantation.MethodsThis is a retrospective observational study carried out at Eye Hospital of Wenzhou Medical University, Zhejiang, China. Patients with uncontrolled glaucoma who underwent AGV implantation alone or combined with phacoemulsification (AGV-Phaco) in the hospital from April 1, 2013 to July 31, 2016 were included. The preoperative and postoperative CCD was defined when the detachment between ciliary body and choroid was detected by the ultrasound biomicroscopy (UBM) and anterior segment optical coherence tomography (AS-OCT) respectively. The main outcomes included the incidence of CCD and the success rate at 6 months after surgery.ResultsIn total, 97 male and 56 female patients were included. CCD was observed in 92 (57.8%) eyes. The glaucoma diagnosis in the Non-CCD and CCD group included primary open angle glaucoma (21(31.3%) vs 33(35.9%)), primary angle closure glaucoma (10(14.9%) vs 13(14.1%)), secondary glaucoma (25(37.3%) vs (28(30.4%)) and so on. The preoperative median IOP (interquartile range) were 21.7(16.0,32.0) mmHg and 23.0(16.0,33.0) mmHg in the Non-CCD group and CCD group. Previous surgical history (95% confidence interval (CI), 1.24 to 13.34; odds ratio (OR) 4.06; p = 0.02) and shorter axial length (95% CI, 0.62 to 0.97 OR 0.78; p = 0.02) were the two risk factors of CCD. The success rate between the CCD and Non-CCD group was not significantly different (64.3% vs 62.5%, p = 0.86) at 6 months.ConclusionsThe incidence of CCD is 57.8% after AGV surgery. Eyes with previous surgical procedure was prone to CCD occurrence and longer axial length was protective against CCD. But at 6 months postoperatively, CCD did not reduce the success rate of AGV surgery and may not be a worrisome complication.

Effects of Early Postoperative Intraocular Pressure after Ahmed Glaucoma Valve Implantation on Long-term Surgical Outcomes.

PurposeTo evaluate the long-term effects of early postoperative intraocular pressure (IOP) after Ahmed glaucoma valve (AGV) implantation on long-term surgical outcomes.MethodsThis retrospective, non-randomized study included 100 eyes of 100 patients who underwent AGV surgery. We divided the enrolled patients into four groups according to the presence of transient hypotony within the first postoperative week or the presence of a hypertensive phase during the first three postoperative months. Postoperative IOP, the number of glaucoma medications, and cumulative success rate were compared among the groups.ResultsThere was significantly better IOP control and a better success rate in the non-hypertensive phase group 2 years postoperatively. However, no significant difference was found in the IOP or success rate at 2 years postoperatively between the transient hypotony and non-hypotony groups. Further subgroup analysis showed that the non-hypotony, non-hypertensive phase group had a significantly higher success rate (100%) at 2 years postoperatively.ConclusionsWe can predict the long-term prognosis after AGV implantation by considering the early postoperative IOP state and the presence of a hypertensive phase.

Changes in Corneal Endothelial Cell after Ahmed Glaucoma Valve Implantation and Trabeculectomy: 1-Year Follow-up.

PurposeTo compare changes in corneal endothelial cell density (CECD) after Ahmed glaucoma valve (AGV) implantation and trabeculectomy.MethodsChanges in corneal endothelium in patients that underwent AGV implantation or trabeculectomy were prospectively evaluated. Corneal specular microscopy was performed at the central cornea using a non-contact specular microscope before surgery and 6 months and 12 months after surgery. The CECD, hexagonality of the endothelial cells, and the coefficient of variation of the cell areas were compared between the two groups.ResultsForty eyes of 40 patients with AGV implantation and 28 eyes of 28 patients with trabeculectomy were studied. Intraocular pressure in the AGV implantation group was significantly higher than that in the trabeculectomy group (p < 0.001), but there was no significant difference in other clinical variables between the two groups. In the AGV implantation group, the mean CECD significantly decreased by 9.4% at 6 months and 12.3% at 12 months compared with baseline values (both, p < 0.001), while it decreased by 1.9% at 6 months and 3.2% at 12 months in the trabeculectomy group (p = 0.027 and p = 0.015, respectively). The changes at 6 months and 12 months in the AGV implantation group were significantly higher than those in the trabeculectomy group (p = 0.030 and p = 0.027, respectively). In the AGV implantation group, there was a significant decrease in the CECD between baseline and 6 months and between 6 months and 12 months (p < 0.001 and p = 0.005, respectively). However, in the trabeculectomy group, a significant decrease was observed only between baseline and 6 months (p = 0.027).ConclusionsBoth the AGV implantation group and the trabeculectomy group showed statistically significant decreases in the CECD 1 year after surgery. The decrease in CECD in the AVG implantation group was greater and persisted longer than that in the trabeculectomy group.

Changes in Corneal Endothelial Cells after Ahmed Glaucoma Valve Implantation: 2-Year Follow-up

To evaluate changes in corneal endothelial cells after Ahmed glaucoma valve (AGV) implantation for the treatment of refractory glaucoma. Observational case series. We prospectively evaluated the change in density and shape of the corneal endothelium in 41 patients (41 eyes) who had undergone AGV implantation for the treatment of refractory glaucoma. Corneal specular microscopy was performed on the superior, supratemporal, supranasal, and central areas with a noncontact specular microscope before surgery and 1, 6, 12, 18, and 24 months after surgery. The changes at each time point were compared with those at baseline and with those of the control group, which consisted of 20 contralateral glaucomatous eyes receiving antiglaucoma medications. The mean follow-up was 19.1 months. The average percentage decrease in corneal endothelial cell count was 5.8% at 1 month, 11.5% at 6 months, 15.3% at 12 months, 16.6% at 18 months, and 18.6% at 24 months after surgery. The changes were statistically significant compared with those at baseline and those of the control eye at all time points during the study period (P < .05). The supratemporal area, the closest site to the tube, showed the greatest decrease in endothelial cell density, by 22.6%, whereas the central cornea showed the smallest decrease, by 15.4%, at 24 months after surgery. There was statistically significant corneal endothelial cell loss in the operated eye after AGV implant surgery. The corneal endothelial cell loss increased with time: 15.3% at 12 months and 18.6% at 24 months after surgery, on average, in all measured areas.

Risk factors of implant exposure outside the conjunctiva after Ahmed glaucoma valve implantation

To study possible risk factors in cases in which part of the device becomes exposed outside the conjunctiva after Ahmed glaucoma valve (AGV) implantation. Eleven eyes in which one part of the AGV was exposed outside the conjunctivae were compared with 44 random eyes that underwent the same operation by the same surgeon during the same time period but without any complications. Preoperative diagnosis, age, sex, implant location, number of previous ocular surgeries, and both associated ocular diseases and systemic diseases were taken into account in both the patient group and the control group to determine all possible causes. Age, implant location, type of glaucoma, diabetes mellitus, and hypertension had no relation to implant exposure. However, the patient group had more ocular surgeries before AGV implantation than the control group (P = 0.006). We found that only the number of previous ocular surgeries was a possible risk factor for implant exposure. More effort should be made to decrease implant exposure outside the conjunctiva, and research should be performed to determine the proper treatment for implant exposure.