Clinical Effectiveness, Humanistic And Economic Evaluation Of The Canaloplasty/ Trabeculotomy Surgical System For Primary Open-Angle Glaucoma: A Systematic Literature Review And Meta-Analysis

Globally, glaucoma is the second leading cause of blindness, and the primary cause of irreversible blindness. The only modifiable risk factor for glaucoma is elevated intraocular pressure (IOP) and long-term data have demonstrated that an IOP <18 mmHg is associated with little or no change in visual field defect. Accounting for >70% of cases, the most common form of glaucoma is primary open-angle glaucoma (POAG). Management of POAG typically includes pharmaceutical options (i.e., eye drops), however these treatments create a burden for patients that can negatively affect their quality of life. 

The canaloplasty/trabeculotomy surgical system (CTSS) is increasingly being utilized for the treatment of POAG. This systematic literature review (SLR) and meta-analysis aim to evaluate the evidence for CTSS and previous iterations (Visco360 and Trab360). This SLR was conducted in accordance with the PRISMA guidelines. The protocol was registered on PROSPERO (CRD42024536680). 

MEDLINE^®, Web of Science™ and the Cochrane databases were searched for publications published between January 2016 and April 2024. A grey literature search was conducted in July 2024, and selected conference proceedings (2021–2024) were also searched. Of 94 publications identified, 29 publications of 22 unique studies met the predefined inclusion criteria for data extraction and analysis. The risk of bias was assessed. Data synthesis was carried out using meta-analysis. Timepoints analyzed were 6, 12, 24 and 36 months. Outcomes included IOP reduction, number of medications, percentage of medication-free patients, and patients with treatment success (defined as IOP reduction ≥20% from baseline).

This SLR and meta-analysis demonstrated that CTSS achieves sustained and clinically meaningful reductions in IOP over time. Mean IOP was consistently maintained below 18 mmHg with reported values ranging from 11.5–17.2 mmHg at month 12 when CTSS was used as standalone intervention or combined with cataract surgery. Whilst there was less data at months 24 and 36, the evidence suggested that reduction in IOP remained stable. The percentage of patients who were medication-free ranged from 34.2% to 78% during the follow up period of 6–36 months. The meta-analysis showed that 66–68% of patients treated with either standalone or combined treatments remained medication-free at 6 and 12 months. Adverse events were predominantly mild and transient.

CTSS demonstrates a favorable safety and effectiveness profile and is thus a beneficial treatment option for patients with POAG. Low IOP values are associated with reduced visual field progression, and effective treatments should achieve an IOP of ≤18 mmHg. The analysis demonstrated reductions in IOP ≤18 mmHg at 6,12 and 24 months postoperatively, with sustained reductions over 36 months. CTSS also reduced the use of glaucoma medication, showing the potential to reduce the burden of treatment, improve adherence and patient quality of life. Limitations of this SLR include the absence of randomized controlled trials. Additional research is required to evaluate effectiveness beyond 36 months, and outcomes for specific patient populations.