The treatment of refractory Glaucoma is a difficult problem in clinical ophthalmology. For refractory glaucoma patients with hyphema, shallow anterior chamber, anterior conglutination of peripheral chamber angle, corneal endothelium dystrophy or decompensated, at present, there is no effective treatment. In order to solve this problem, a new type posterior integral glaucoma valve with IOP control device was designed using medical titanium alloy, and the valve model was established by Abaqus software, and the stiffness and preload of the valve were analyzed by finite element method. The results showed that the opening and closing of the valve were controlled automatically by the pressure difference between the front and back of the valve, and the opening and flow rate of the valve increase dynamically with the increase of intraocular pressure, and finally reached the set ideal IOP value of steady state.
Finite Element Analysis ; Follow-Up Studies ; Glaucoma ; Glaucoma Drainage Implants ; Humans ; Intraocular Pressure ; Treatment Outcome

Objective: We reported a case of Descemet's membrane detachment (DMD) following ripcord removal of a Baerveldt shunt in a post-corneal transplant eye, and the interventions done. Method: This is a case report Results: A 65-year-old male with multiple surgeries (phacoemulsification, two corneal transplants, and Baerveldt shunt implantation) in the right eye developed increased intraocular pressures, prompting removal of the intraluminal stent (ripcord) of the shunt. This was complicated by hypotony and DMD. Ripcord reinsertion and viscoelastic injection were performed to reattach the Descemet's membrane (DM) but failed. 0.1mL of 14% perfluoropropane (C3F8) gas was injected into the anterior chamber that successfully reattached the DM with return to pre-operative best-corrected visual acuity after 1 week. Conclusion Injection of an expansive gas (C3F8) was effective in repairing a corneal graft DMD in an eye with a Baerveldt shunt.
Glaucoma Drainage Implants ; Corneal Transplantation

PURPOSE: To evaluate outcomes and factors associated with surgical failure in patients who underwent combined phacoemulsification and Ahmed glaucoma valve (AGV) implantation. METHODS: This retrospective and longitudinal study enrolled 40 eyes (38 patients) that underwent combined phacoemulsification and AGV implantation. Visual acuity, intraocular pressure (IOP), and number of antiglaucoma medications were evaluated preoperatively and postoperatively. Complete success was defined as a last follow-up IOP of 6 to 21 mmHg without medication, qualified success as an IOP of 6 to 21 mmHg with medication, and failure as an IOP of >21 or <6 mmHg. RESULTS: The mean follow-up period was 18 ± 10 months. Preoperative diagnoses were chronic angle closure glaucoma (35.0%), neovascular glaucoma (22.5%), uveitic glaucoma (17.5%), primary open-angle glaucoma (15.0%), and other (10.0%). IOP decreased from a mean of 30.5 ± 8.7 to 14.5 ± 3.7 mmHg at the last follow-up visit (p < 0.001). Treatment was classified as qualified success in 18 eyes (45%), complete success in 15 (37.5%), and failure in seven (17.5%). Twenty-two eyes (55%) showed improvement in visual acuity. The most common postoperative complication was a transient hypertensive phase (five eyes, 12.5%). Tube-iris touch was associated with surgical failure (hazard ratio, 8.615; p = 0.008). CONCLUSIONS: Combined phacoemulsification and AGV implantation is an effective and safe surgical option for patients with refractory glaucoma and cataract. Postoperative tube-iris touch is an indicator of poor prognosis.
Cataract ; Diagnosis ; Follow-Up Studies ; Glaucoma Drainage Implants ; Glaucoma* ; Glaucoma, Angle-Closure ; Glaucoma, Neovascular ; Glaucoma, Open-Angle ; Humans ; Intraocular Pressure ; Longitudinal Studies ; Phacoemulsification* ; Postoperative Complications ; Prognosis ; Retrospective Studies ; Visual Acuity

When vitrectomy is performed in eyes that have undergone glaucoma surgery, the site of sclerotomy often overlaps with the previous glaucoma operation site. It can lead to serious complications such as postoperative hypotony, leakage, and/or infection. Our technique involves modification of surgeon's position and two sclerotomy sites 45° away from the original position, with an infusion cannula inserted infranasally to avoid damage to the glaucoma drainage implant or filtering bleb. The modified approach was applied to seven eyes with various indications. Vitrectomy was successfully completed, and there were no sclerotomy site complications, leakage, or hypotony in any case. Good intraocular pressure control was maintained throughout the postoperative course in all cases.
Blister* ; Catheters ; Filtering Surgery ; Glaucoma Drainage Implants* ; Glaucoma* ; Humans ; Intraocular Pressure ; Vitrectomy*

PURPOSE: To compare changes in corneal endothelial cell density (CECD) after Ahmed glaucoma valve (AGV) implantation and trabeculectomy. METHODS: Changes 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. RESULTS: Forty 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). CONCLUSIONS: Both 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.
Cell Count ; Endothelium, Corneal/*pathology ; Female ; Follow-Up Studies ; Glaucoma/diagnosis/physiopathology/*surgery ; *Glaucoma Drainage Implants ; Humans ; *Intraocular Pressure ; Male ; Middle Aged ; Postoperative Period ; Prospective Studies ; Prosthesis Implantation/*methods ; Time Factors ; Trabeculectomy/*methods ; Treatment Outcome

PURPOSE: We explored the performance of and pressure elevation caused by small-diameter microtubes used to reduce overfiltration. METHODS: Using a syringe pump-driven constant-flow setting (2 µL/min), pressures were measured for polytetrafluoroethylene (PTFE) microtubes 5 mm in length with inner diameters of 51, 64, and 76 µm and for polyether block amide (PEBAX) microtubes with an inner diameter of 76 µm. Experiments (using microtubes only) were initially performed in air, water, and enucleated pig eyes and were repeated under the same conditions using intraluminal 9/0 nylon stents. RESULTS: The pressures measured in air in 51-, 64-, and 76-µm-diameter PTFE microtubes differed significantly (22.1, 16.9, and 12.2 mmHg, respectively; p < 0.001), and that of the 76-µm-diameter PEBAX microtube was 15.8 mmHg (p < 0.001 compared to the 12.2 mmHg of the 76-µm-diameter PTFE microtube). The pressures measured in water also differed significantly among the three microtubes at 3.9, 3.0, and 1.4 mmHg, respectively, while that in the PEBAX microtube was 2.6 mmHg (all p < 0.001). Using the intraluminal stent, the pressure in water of the three different PTFE microtubes increased to 22.6, 18.0, and 4.1 mmHg, respectively, and that in the PEBAX microtube increased to 10.5 mmHg (all p < 0.001). Similar trends were evident when measurements were performed in pig eyes. CONCLUSIONS: Although microtubes of smaller diameter experienced higher pressure in air, reduction of the inner diameter to 51 µm did not adequately increase the pressure attained in water or pig eyes. Insertion of an intraluminal stent effectively elevated the latter pressures. PEBAX microtubes created higher pressures than did PTFE microtubes.
Animals ; Disease Models, Animal ; Glaucoma/physiopathology/*surgery ; *Glaucoma Drainage Implants ; Intraocular Pressure/*physiology ; Ophthalmologic Surgical Procedures/*instrumentation ; *Polytetrafluoroethylene ; Prosthesis Design ; Swine

PURPOSE: To compare the surgical results of trabeculectomy and Ahmed glaucoma valve implantation after a previous failed trabeculectomy. METHODS: A retrospective comparative case series review was performed on 31 eye surgeries in 20 patients with primary congenital glaucoma who underwent trabeculectomy or Ahmed glaucoma valve implantation after a previous failed trabeculectomy with mitomycin C. RESULTS: The preoperative mean intraocular pressure was 25.5 mmHg in the trabeculectomy group and 26.9 mmHg in the Ahmed glaucoma valve implantation group (p = 0.73). The 48-month postoperative mean intraocular pressure was 19.6 mmHg in the trabeculectomy group and 20.2 mmHg in the Ahmed glaucoma valve implantation group (p = 0.95). The 12-month trabeculectomy success rate was 69%, compared with 64% for Ahmed glaucoma valve implantation, and the 48-month success rates were 42% and 36% for trabeculectomy and valve implantation, respectively. The success rates following the entire follow-up period were not significantly different between the two groups (p > 0.05 by log rank test). Postoperative complications occurred in 25% of the trabeculectomy-operated eyes and 9% of the Ahmed-implanted eyes (p = 0.38). CONCLUSIONS: There was no significant difference in surgical outcome between the trabeculectomy and Ahmed glaucoma valve implantation groups, neither of which had favorable results. However, the trabeculectomy group demonstrated a higher prevalence of adverse complications such as post-operative endophthalmitis.
Child, Preschool ; Female ; Follow-Up Studies ; Glaucoma/congenital/physiopathology/*surgery ; *Glaucoma Drainage Implants ; Humans ; Infant ; Intraocular Pressure/*physiology ; Male ; Mitomycin/*adverse effects ; Nucleic Acid Synthesis Inhibitors/adverse effects ; Reoperation ; Retrospective Studies ; Time Factors ; Trabeculectomy/*adverse effects/*methods ; Treatment Failure ; Treatment Outcome ; *Visual Acuity

BACKGROUNDNeovascular glaucoma is a refractory disease, and difficult to manage. The aim of this study was to evaluate the clinical outcomes of Ahmed glaucoma valve implantation (AGVI) in neovascular glaucoma (NVG) and non-NVG patients.

METHODSThis prospective, non-randomized study included 55 eyes of 55 patients with refractory glaucoma; 27 had NVG (NVG group) and 28 had non-NVG (non-NVG group). All of the patients underwent AGVI. The NVG group was adjunctively injected with intravitreal ranibizumab/bevacizumab (IVR/IVB) before AGVI. Intraocular pressure (IOP) was the primary outcome measure in this study. Surgical success rate, number of antiglaucoma medications used, best corrected visual acuity (BCVA), and postoperative complications were analyzed between the groups.

RESULTSAll of the patients completed the study (follow-up of 12 months). Kaplan-Meier survival curve analysis indicated that the qualified success rates in the NVG and non-NVG groups at 12 months were 70.5% and 92.9%, respectively; this difference was significant (P = 0.036). The complete success rates in the NVG and non-NVG groups at 12 months were 66.7% and 89.3%, respectively (P = 0.049). Compared with preoperative examinations, the postoperative mean IOP and use of medications were significantly lower at all follow-up time points in both groups (all P < 0.05). There were significant differences in BCVA between the two groups at the 12-month follow-up (χ(2) = 9.86, P = 0.020). Cox proportional hazards regression showed NVG as a risk factor for surgical failure (RR = 15.08, P = 0.033). Postoperative complications were similar between the two groups.

CONCLUSIONSAGVI is a safe and effective procedure in refractory glaucoma, but the success rate of surgery was related to the type of refractory glaucoma. The complete and qualified success rates of NVG patient adjunctive anti-vascular endothelial growth factor treatment are still lower than those of non-NVG patients.

Adult ; Aged ; Female ; Glaucoma ; surgery ; Glaucoma Drainage Implants ; Glaucoma, Neovascular ; surgery ; Humans ; Male ; Middle Aged ; Proportional Hazards Models ; Prospective Studies

OBJECTIVE: To compare the intraocular pressure control of trabeculectomy with mitomycin-C (Trab MMC) versus glaucoma drainage device (GDD) implantation in glaucoma management after penetrating keratoplasty (PKP).
METHODS: A review of medical records of patients who developed glaucoma after penetrating keratoplasty and underwent either trabeculectomy with mitomycin-C augmentation or glaucoma drainage device implantation between October 2006 to June 2012 at a tertiary referral eye center was done. The following information were obtained for each patient: age, gender, corneal diagnosis before keratoplasty, details of keratoplasty in terms of graft versus donor size, other simultaneous operations, visual acuity (VA), intraocular pressure (IOP), number of glaucoma medications before and after PKP, graft status before glaucoma treatment and at the final visit, type of glaucoma before treatment, and the glaucoma procedure performed and its complications if any. Three primary outcomes were evaluated: graft status, postoperative IOP, and VA. Controlled IOP with or without medications was defined as IOP greater than 6 but less than 20. Paired t-test determined the significant decrease in the mean IOP control and the number of medications before and after keratoplasty. Single-factor analysis of variance (ANOVA) determined if there were significant differences in the mean between the two surgeries. Kaplan-Meier survival analysis compared the surgeries in their effects on graft clarity.
RESULTS: Out of the 222 medical records reviewed, 23 patients met the inclusion criteria. Twelve (52.2%) eyes had clear grafts after glaucoma surgery; 8 (72.7%) in the Trab MMC and 4 (33.3%) in the GDD groups. Twenty-one (91.3%) eyes had controlled IOP; 9 (81.8%) had Trab MMC, 12 had GDD surgeries. There was no difference (p = 0.07) in percentage of patients with controlled IOP between the 2 groups. Mean IOP in the Trab MMC (32.6 ± 4.3 to 15.1 ± 4.0, p = 0.004) and GDD (23.6 ± 4.6 to 12.5 ± 0.8, p = 0.04) groups significantly decreased after the procedures. The decrease in mean IOP was not different (p = 0.55) between the 2 groups. The number of patients with controlled IOP increased significantly (p = 0.02) in the Trab MMC group. There were no differences in the mean number of glaucoma medications between both groups before (p = 0.92) and after (p = 0.18) glaucoma surgery. There was no difference (p = 0.17) in the survival distribution of controlled IOP between the 2 surgeries.
CONCLUSION: Trabeculectomy with mitomycin-C augmentation and glaucoma drainage device implantation are effective methods of controlling IOP post penetrating keratoplasty. There was no difference between the two groups in controlling the IOP and in reducing the number of glaucoma medication postoperatively.

Human ; Male ; Female ; Aged ; Middle Aged ; Adult ; Trabeculectomy ; Keratoplasty, Penetrating ; Intraocular Pressure ; Mitomycin ; Corneal Transplantation ; Tonometry, Ocular ; Glaucoma Drainage Implants ; Glaucoma ; Cornea

BACKGROUNDAhmed Glaucoma Valve implantation (AGVI) is used to treat refractory glaucoma. Breakdown of the blood-aqueous barrier (BAB) has been noted after some surgical techniques. The current study was designed to assess BAB disruption after AGVI.

METHODSAnterior chamber protein content was measured by the laser flare cell photometry in 22 eyes of 22 patients with refractory glaucoma before AGVI and at each postoperative visit up to 1 month.

RESULTSBefore AGVI the mean aqueous flare values in all eyes were (15.17 ± 9.84) photon counts/ms. After AGVI, the values significantly increased at day 1, day 3, and week 1 compared to those before AGVI (all P < 0.05) with a peak at day 3. They returned to pre-operative levels at week 2, and were lower than preoperative level at month 1. Eyes with previous intraocular surgery history had greater aqueous flare values than those without previous intraocular surgery history, but there were no significant differences at all time points postoperatively (all P > 0.05). Furthermore, eyes with shallow anterior chambers had greater aqueous flare values at day 3 and week 1 (all P < 0.05). When comparing eyes with other refractory glaucoma conditions, neovascular glaucoma combined with intravitreal bevacizumab injection resulted in lower aqueous flare values after AGVI, but no significant differences were observed at all time points, postoperatively (all P > 0.05).

CONCLUSIONSThe BAB was impaired and inflammation was present in the anterior chamber in refractory glaucomatous eyes following AGVI. However, such conditions were resolved within 1 month postoperatively. Intravitreal bevacizumab treatment in neovascular glaucoma eyes before AGVI may prevent BAB breakdown.

Adult ; Aqueous Humor ; physiology ; Blood-Aqueous Barrier ; pathology ; Female ; Glaucoma Drainage Implants ; adverse effects ; Humans ; Male ; Middle Aged ; Prospective Studies