To evaluate reduction in intraocular pressure (IOP) and medications for open-angle glaucoma (OAG) patients 12 months post-ab-interno circumferential viscodilation (VISCO360, Sight Sciences, Menlo Park, CA) in conjunction with cataract surgery.Surgical center (New York, United States).Retrospective study of all OAG patients treated with 360-degree ab-interno viscodilation with cataract surgery by a single surgeon (NR) having 12 months of follow-up. Eyes were stratified by baseline IOP. Group 1: ≥18 mmHg (n=111). Group 2: 10 mmHg >30 days post-op 1.1%, mild inflammation <1%) and no secondary surgical interventions excepting a single paracentesis, one-day postoperative.Treatment goals for the two groups differed. Pressure reduction (Group 1) or medication reduction (Group 2). Viscodilation achieved significant IOP reduction in Group 1 and medication reduction in Group 2 with many patients (both groups) medication free at 12 months. AE were infrequent and transient.Circumferential ab-interno viscodilation can be combined with cataract surgery and provide an IOP lowering and medication reduction benefit sustained for at least 12 months, for many patients with OAG.