Efficacy of Intravitreal Ranibizumab Combined With Ahmed Glaucoma Valve Implantation for the Treatment of Neovascular Glaucoma

Min Tang; Yang Fu; Ying Wang; Zhi Zheng; Ying Fan; Xiaodong Sun; Xun Xu

Disclosures

BMC Ophthalmol. 2016;16(7) 

In This Article

Methods

This study was a prospective, non-randomized, open-label, controlled study. This study enrolled patients admitted to the Department of Ophthalmology of Shanghai General Hospital from December 2012 to March 2014. Inclusion criteria were: 1) NVG patients (NVG was diagnosed by the presence of active neovascularization in the iris and/or angle, high intraocular pressure (IOP > 21 mm Hg, 1 mm Hg = 0.133 kPa, Goldmann applanation tonometer) and underlying ischemic retinal diseases); 2) IOP > 21 mm Hg, with or without anti-glaucoma medications or panretinal photocoagulation (PRP) before; 3) 18 to 85 years old; 4) patients who chose IVR before AGV implantation or AGV implantation only should complete a follow-up of six to 12 months. Exclusion criteria were: 1) patients combined with other types of glaucoma or other serious eye diseases; 2) patients who had received glaucoma surgery or other intraocular surgery in either eye; 3) patients who had received intravitreal injection in either eye within three months before surgery; 4) patients who failed to complete the scheduled follow-ups for various reasons; 5) IOP measurements were made inaccurate for various reasons; 6) IOP decreased (<= 21 mm Hg) after IVR and/or PRP; 7) cataract surgery or vitreous surgery was needed during the primary surgery; 8) surgery or intravitreal injection was required for both eyes; and 9) pregnant patients or patients combined with other serious uncontrolled medical diseases. This study was approved by the Ethics Committee of Shanghai General Hospital (registration number: 2012 K061), and it was registered with the Chinese Clinical Trial Registry (registration number: ChiCTR-OOC-14005709). All patients signed an informed consent before participation in this study.

Grouping method: NVG patients through preliminary screening would be educated about IVR on its effect, side-effect, risks, price and so on, then they chose to accept IVR before AGV implantation (injection group) or AGV implantation only (control group) at the discretion of themselves and signed an informed consent.

Endpoints were: 1) completion of the scheduled follow-up over the 6-month or 12-month period; 2) failure to be followed up as scheduled, being lost to follow up, undergoing intraocular surgery including cyclophotocoagulation during the follow-up period, or receiving intravitreal injection during the follow-up period (collectively referred to as dropouts).

We tried to do PRP for patients before IVR or AGV implantation if possible, and evaluated again whether they needed IVR or AGV implantation. As to those who could not accept PRP due to very high IOP or corneal edema pre-surgery, we applied this therapy just after surgery (usually 1 or 2 weeks later). Patients would not be enrolled if their IOPs were controlled by PRP before AGV implantation (IOP ≤21 mm Hg).

IVR was performed three to 14 days prior to AGV implantation. Under topical anesthesia, a needle was introduced through the conjunctival surface 3.8 mm from the corneal limbus in the affected eye for intravitreal injection of 0.5 mg/0.05 mL ranibizumab (Lucentis, 10 mg/mL; Novartis, Basel, Switzerland). The puncture site was pressed with a cotton swab for 5 to 10 s after the needle was withdrawn. IOP and light perception were examined. Sometimes anterior chamber paracentesis was performed in patients with higher IOP. All patients were observed more than three days. After that, AGV implantation would be performed, once the IOPs of patients reached 40 mm Hg during time, or it would be done two weeks after IVR. Otherwise, Patients would not be enrolled by the study if their IOPs were controlled just by IVR (IOP ≤21 mm Hg).

AGV implantation was performed under peribulbar anesthesia, a fornix-based conjunctival flap superior and temporal to the affected eye was prepared until the equator and a mitomycin C-soaked (0.4 mg/mL) cotton swab was applied to the area for two to five minutes before rinsing thoroughly with saline. An AGV (Model FP7) drainage plate was fixed with 6–0 suture on the surface of the sclera, with its anterior border 8 to 10 mm from the limbus. A 27G needle was introduced into the interlamellar space of the sclera 5 mm behind the limbus and pushed forward until into the anterior chamber, where viscoelastic agent was injected while the needle was being withdrawn slowly. A drainage tube was implanted into the anterior chamber two to three mm deep through the needle tract, and was mildly ligated with 8–0 absorbable suture (6 to 7 mm behind the limbus) before the conjunctival flap was tightly stitched. A small amount of aqueous humor was drained through a clear corneal if necessary incision to bring intraocular pressure slightly higher than normal IOP. All the procedures were completed by the authors.

Levofloxacin eye drops were applied at short intervals before surgery. Tobramycin and dexamethasone ophthalmic solution was applied postoperatively once every two hours for a total of three days, followed by four times a day for two weeks. Tropicamide or atropine was administered for two weeks for pupil dilation treatment where appropriate. Some patients received panretinal photocoagulation within one month after surgery. Anti-glaucoma medications were administered in light of IOP during follow-up.

The mean of three consecutive outpatient IOP measurements just before surgery was used as the baseline IOP. Patients were followed up on schedule (1–3d, 2w ± 1d, 1m ± 3d, 3m ± 5d, 6m ± 7d, 12m ± 14d) after surgery. Best corrected visual acuity (BCVA) and IOP were determined and slit-lamp microscopy with a preset lens was performed as a routine. Other tests including gonioscopy, ultrasound biomicroscopy, perimetry and retinal nerve fiber layer scan were conducted in selected patients where appropriate. IOP, surgical success rate, BCVA, anti-glaucoma medications and postoperative complications were used as major outcome measures at each follow-up time interval. Surgical success was defined as IOP > = 6 mm Hg and < = 21 mm Hg, with or without the use of anti-glaucoma medications, and without severe complications or reoperation.[7] Surgical failure was defined as IOP persistently ≥6 mm Hg or ≤21 mm Hg for more than two weeks, or loss of light perception, or the occurrence of any serious complication including endophthalmitis, corneal decompensation, malignant glaucoma, severe choroidal detachment (>180°), severe choroidal hemorrhage (>180°), retinal detachment, ocular atrophy, or displacement, withdrawal or exposure of drainage tube, or necessity of reoperation for other reasons.

Statistical analysis was performed using statistical package SAS9.13. Differences in gender and diagnoses at baseline and postoperative complications, and dropout rates during follow-up were compared between the two groups using chi-square, corrected chi-square test or Fisher's exact probability test. Differences in age, IOP, BCVA, and medications at baseline and IOP decline, BCVA, and medications during follow-up were compared using the t test. Difference in success rates throughout follow-up was compared using the Log-Rank test. P value < 0.05 was considered statistically significant.

Comments

3090D553-9492-4563-8681-AD288FA52ACE

processing....