Pars plana Baerveldt tube insertion with pars plana vitrectomy for refractory glaucoma

Two Year Randomized Prospective Comparison of Ahmed Valve Versus Baerveldt Implant in Vitrectomized Eyes

PRCIS

Ahmed Valve and Baerveldt shunt are efficacious options in vitrectomized eyes. Baerveldt implant achieves a lower mean intraocular pressure (IOP) at 2 years, with fewer medications and a higher percentage of medication-free patients.

PURPOSE

To investigate and compare the efficacy and complications between Ahmed FP7 Glaucoma Valve (AGV) and Baerveldt 101-350 Glaucoma Implant (BGI) in vitrectomized eyes.

MATERIALS AND METHODS

In this single-center randomized clinical trial, 43 vitrectomized eyes (39 patients) underwent glaucoma drainage device implantation. Eyes were randomized to receive either an AGV (FP7) or a BGI (101-350) and were followed for 2 years. Surgical success was defined as an IOP measurement≤18 mm Hg and≥5 mm Hg with or without glaucoma medication at 2 or more sequential visits after 3 months. The primary outcome was the comparison of the success rate at 2 years, while mean IOP, mean number of medications, and number of complications were considered secondary outcomes.

RESULTS

Kaplan-Meier estimates of the 2-year success rates in IOP control after GDD implantation were similar between the 2 groups; AGV group 81.8% (95% CI: 67.2%-99.6%) and BGI group 85.7% (95% CI: 72.0%-100.0%), (log-rank test P value = 0.74). Patients in the BGI group had a statistically significant lower mean IOP compared with the AGV group in all follow-up visits at 2, 6, 12, and 24 months (11.62 vs. 17.45 mm Hg at the latter P value <0.001). The BGI group required a significantly lower number of medications for IOP control at the 2-year visit compared with the AGV group (0.76±0.99 vs. 1.5±1.06 P value = 0.02) but had a higher number of complications (62% vs. 41%, respectively).

CONCLUSIONS

GDDs provide a viable solution for IOP control in vitrectomized eyes. Based on our prospective comparison, both Ahmed FP7 Glaucoma Valve and Baerveldt 101-350 Glaucoma Implant are efficacious options.

Pars plana Aurolab aqueous drainage implantation for refractory glaucoma: Outcome of a new modified technique

PURPOSE

To report the outcomes of pars plana insertion of Aurolab aqueous drainage implant (AADI) in adults with refractory glaucoma by the novel technique of making scleral tunnel instead of patch graft to cover the tube to prevent its migration.

METHODS

A retrospective study was done between April 2016 and April 2018 on patients with ≥12 months of follow-up. The main outcome measure was a surgical failure at 12 months. The failure was defined as intraocular pressure (IOP) >18 mmHg or IOP ≤5 mmHg on two consecutive follow-up visits after 3 months, reoperation for glaucoma, loss of light perception vision, or implant explantation. Alternate definitions of failure including IOP >21 and IOP >15 mmHg were also considered.

RESULTS

: The study included 32 eyes of 32 patients. The mean age was 46.2 ± 17.5 years. The most common etiology is traumatic glaucoma (12 eyes, 37.5%). The mean preoperative IOP and anti-glaucoma medications were 43.3 ± 10.3 and 3.4 ± 0.5 mmHg, respectively; both the parameters at the final follow-up were reduced to 15.2 ± 8.1 and 1.6 ± 0.5 mmHg. The Kaplan-Meier survival estimates demonstrated that the cumulative probability of failure was 15.6% (95% CI; 6.8-33.5%) at 3 months, 18.7% (95% CI; 8.9-37.0%) at 6 months, and 25.0% (95% CI; 13.4-43.8%) at 12 months.

CONCLUSION

Pars plana AADI implantation with a newer modification technique is a useful procedure in reducing IOP and the number of anti-glaucoma medications in the eyes with refractory glaucoma. The visual acuity may be stabilized with the concurrent treatment of posterior segment pathology.

Conventional glaucoma implants and the new MIGS devices: a comprehensive review of current options and future directions

Glaucoma is a progressive optic neuropathy that is the second leading cause of preventable blindness worldwide, after cataract formation. A rise in the intraocular pressure (IOP) is considered to be a major risk factor for glaucoma and is associated with an abnormal increase of resistance to aqueous humour outflow from the anterior chamber. Glaucoma drainage devices have been developed to provide an alternative pathway through which aqueous humour can effectively exit the anterior chamber, thereby reducing IOP. These devices include the traditional aqueous shunts with tube-plate design, as well as more recent implants, such as the trabeculectomy-modifying EX-PRESS^® implant and the new minimally invasive glaucoma surgery (MIGS) devices. In this review, we will describe each implant in detail, focusing on their efficacy in reducing IOP and safety profile. Additionally, a critical and evidence-based comparison between these implants will be provided. Finally, we will propose potential developments that may help to improve the performance of current devices.

Needle guided ab interno technique for tube insertion through the ciliary sulcus in uncontrolled glaucoma

PURPOSE

To describe a modified ab interno technique for the tube implantation from a glaucoma draining device into the ciliary sulcus.

MATERIALS AND METHODS

The modified ab interno technique was performed on four eyes of four patients.

RESULTS

After the plate was fixed, a 21G needle is inserted through a paracentesis 180° away from the tube position into the anterior chamber and advanced to the posterior chamber through the sclera; finally, the needle exits the eye, then the tube is inserted into the lumen of the needle. The tube is then inserted simultaneously as the 21G needle is pulled out so the tube is placed on the ciliary sulcus.

CONCLUSIONS

We report a simple and novel technique for the tube implantation from a glaucoma draining device into the ciliary sulcus, in which the tube is guided with a 21G needle from an accessory paracentesis in order to achieve a posterior placement of the tube.

Combined pars plana glaucoma drainage device placement and vitrectomy using a vitrectomy sclerotomy site for tube placement: a case series

Purpose

The purpose of this study is to report the safety and efficacy of pars plana glaucoma drainage devices with pars plana vitrectomy using one of the vitrectomy sclerotomy sites for tube placement in patients with refractory glaucoma.

Methods

Retrospective case series of 28 eyes of 28 patients who underwent combined pars plana glaucoma drainage device and pars plana vitrectomy between November 2016 and September 2019 at Massachusetts Eye and Ear. Main outcome measures were intraocular pressure (IOP), glaucoma medication burden, best corrected visual acuity, and complications. Statistical tests were performed with R and included Kaplan-Meier analyses, Wilcoxon paired signed-rank tests, and Fisher tests.

Results

Mean IOP decreased from 22.8 mmHg to 11.8 mmHg at 1.5 years (p = 0.002), and mean medication burden decreased from 4.3 to 2.1 at 1.5 years (p = 0.004). Both IOP and medication burden were significantly lower at all follow-up time points. The probability of achieving 5 < IOP ≤ 18 mmHg with at least 20% IOP reduction from preoperative levels was 86.4% at 1 year and 59.8% at 1.5 years. At their last visit, three eyes (10.7%) achieved complete success with IOP reduction as above without medications, and 14 eyes (50.0%) achieved qualified success with medications. Hypotony was observed in 1 eye (3.6%) prior to 3 months postoperatively and 0 eyes after 3 months. Visual acuity was unchanged or improved in 23 eyes (82.1%) at their last follow-up. Two patients had a visual acuity decrease of > 2 lines. Two eyes required subsequent pars plana vitrectomies for tube obstruction, and one eye had transient hypotony.

Conclusions

The results of pars plana glaucoma drainage device and pars plana vitrectomy using one of the vitrectomy sclerotomy sites for tube placement are promising, resulting in significant IOP and medication-burden reductions through postoperative year 1.5 without additional risk of postoperative complications. Inserting glaucoma drainage devices into an existing vitrectomy sclerotomy site may potentially save surgical time by obviating the need to create another sclerotomy for tube placement and suture one of the vitrectomy ports.

Combined pars plana vitrectomy and pars plana Baerveldt tube placement in eyes with neovascular glaucoma

PURPOSE

To describe characteristics and outcomes of combined pars plana vitrectomy and Baerveldt tube insertion procedure from 2005 to 2010 in eyes with neovascular glaucoma.

METHODS

Seventy-nine patients (89 eyes) with ≥2 months of follow-up were included. Outcome measures were visual acuity, intraocular pressure (IOP), number of glaucoma medications, and complications. Changes in mean logMAR visual acuity, IOP, and glaucoma medications were compared by a two-tailed t-test.

RESULTS

Mean patient age was 69.0 years. Forty-three (54%) were male. Mean follow-up time was 19.9 months. Most common causes of neovascular glaucoma was diabetes (n = 63 [71%]) and central retinal vein occlusion (n = 21 [24%]). Eighty-six eyes (97%) underwent a 250 mm Baerveldt drainage device and 3 (3.4%) a 350 mm Baerveldt. Forty-five (51%) 20-gauge, 12 (13%) 23-gauge, and 32 (36%) 25-gauge pars plana vitrectomies were performed. Fifty-two eyes (58%) preoperatively and 23 (33%) postoperatively received intraocular injections for rubeosis and macular edema. Mean ± standard deviation logMAR visual acuity at 18-, 24-, 36-, and 48-month follow-up time points was significantly better than preoperative vision (P < 0.05). Preoperative versus final IOP and number of glaucoma medications were significantly decreased (P < 0.05). Fourteen eyes (16%) had a final visual acuity of no light perception. Most common complications included transient ocular hypertension (n = 82 [92%]), transient hypotony (n = 20 [22%]), hyphema (n = 19 [21%]), corneal edema (n = 17 [19%]), and vitreous hemorrhage (n = 14 [16%]). The frequency of transient hypotony, vitreous hemorrhage, and rubeosis was significantly (P < 0.05) higher in 20-gauge versus 23-/25-gauge pars plana vitrectomy eyes. Nine eyes (10%) required return to the operating room after combined procedure, including 4 eyes (4.5%) for retinal detachment and 3 (3.4%) for high IOP due to tube occlusion. Three eyes (3.4%) developed endophthalmitis and 2 (2.2%) progressed to being pre/phthisical (none were enucleated).

CONCLUSION

Combined pars plana vitrectomy and Baerveldt glaucoma shunt may be a useful procedure in reducing IOP and number of glaucoma medications in eyes with neovascular glaucoma along with stabilizing visual acuity in a majority of these eyes. Further studies are warranted to verify and expand on these findings.