<p>Twelve-Month Outcomes of Stand-Alone Excisional Goniotomy in Mild to Severe Glaucoma</p>

Abstract

Purpose To describe 12-month intraocular pressure (IOP) and medication use outcomes following excisional goniotomy (EG) as a stand-alone procedure in eyes with medically uncontrolled glaucoma. Methods This was a retrospective analysis of data from surgeons at 8 centers (6 US, 2 Mexico). Eyes with glaucoma undergoing standalone EG with a specialized instrument (Kahook Dual Blade, New World Medical, Rancho Cucamonga, CA) for IOP reduction and followed for 12 months postoperatively were included. Data were collected preoperatively, intraoperatively, and 1 day, 1 week, and 1, 3, 6, and 12 months postoperatively. The primary outcome was reduction from baseline in IOP, and key secondary outcomes included IOP-lowering medication reduction as well as adverse events. Results A total of 42 eyes were analyzed, of which 36 (85.7%) had mild to severe primary open-angle glaucoma (POAG). Mean (standard error) IOP at baseline was 21.6 (0.8) mmHg, and mean number of medications used at baseline was 2.6 (0.2). At 3, 6, and 12 months postoperatively, mean IOP reductions from baseline were 4.6 mmHg (22.3%), 5.6 mmHg (27.7%), and 3.9 mmHg (19.3%) (p≤0.001 at each time point). At the same time points, mean medications reductions of 0.7 (25.8%), 0.9 (32.6%), and 0.3 (12.5%) medications were seen (p<0.05 at months 3 and 6, not significant at month 12). Six eyes (14.3%) underwent additional glaucoma surgery during the 12-month follow-up period. Discussion Standalone EG with KDB can reduce IOP, and in many cases reduce medication use, through up to 12 months in eyes with mild to severe glaucoma. Statistically significant and clinically relevant reductions in IOP were seen at every time point. While the goal of surgery was not to reduce medication burden, mean medication use was significantly reduced at all but the last time point. In the majority of eyes, the need for a bleb-based glaucoma procedure was delayed or prevented for at least 12 months.

<p>Turn Back Elevation of Once Reduced IOP After Trabeculotomy Ab Externo and Kahook Dual Blade Surgeries Combined with Cataract Surgery</p>

“…Regeneration and scaring of the angle tissue in both techniques may progress over years, and lead to higher IOP at 18 and 24 months than those at three months in both the phaco-KDB and external phaco-trabeculotomy cohorts. In previous reports, re-elevation of IOP 18 or increase in number of postsurgical medications after the canal surgery 17 had been suggested without scientific analysis for the reasons.…”

“…As a first step of external phaco-trabeculotomy, cataract surgery was performed as a first step, and trabeculotomy procedures followed techniques described previously. 17 A metal trabeculotomy probe (Inami Co., Tokyo, Japan) was inserted into the Schlemm’s canal and in-rotated to disrupt the inner wall of the Schlemm’s canal at superior 120 circumferential degrees. Thereafter the scleral flap was secured to be watertight by five 10–0 nylons.…”

Microinvasive Glaucoma Surgery: An Evidence-Based Review

“…The success of IOP reduction seems to depend on the type of glaucoma being treated, with 40%-100% of the eyes achieving a ≥20% reduction in IOP. 26,27 Eyes with OAG and its subtypes appear to reach the 20% reduction mark 42%-72% of the time, whereas ACG patients appear to reach that 20% reduction mark up to 100% of the time. [26][27][28] When the uveitic glaucoma patients with elevated IOP were studied, only about 38% of them achieved the 20% reduction mark.…”

“…26,27 Eyes with OAG and its subtypes appear to reach the 20% reduction mark 42%-72% of the time, whereas ACG patients appear to reach that 20% reduction mark up to 100% of the time. [26][27][28] When the uveitic glaucoma patients with elevated IOP were studied, only about 38% of them achieved the 20% reduction mark. 29 Although the retrospective studies referenced above focus on KDB as a standalone procedure, KDB has been shown to be similarly effective with cataract surgery.…”

Comparison of 12-Month Outcomes of Kahook Dual Blade Excisional Goniotomy Performed by Attending versus Resident Surgeons

“…MIGS denotes a group of minimally invasive ab-interno procedures that have shown promise in the reduction in IOP and medication burden in patients with glaucoma while also significantly decreasing the risk of complications, such as hypotony. [5][6][7] Goniotomy performed with the Kahook Dual Blade ([KDB] New World Medical, Rancho Cucamonga, CA) is a type of Schlemm's canal MIGS procedure that has shown success in lowering IOP and reducing the medication burden in adult glaucoma patients as both a stand-alone procedure (KDB) 8,9 and combined with phacoemulsification (phaco-KDB). 5,7,10 The design of the parallel blade with a ramp allows a precise excision of the diseased trabecular meshwork en bloc to allow the aqueous humor to directly drain through the Schlemm's canal into the collector channels.…”