Interventional procedure overview of ab interno canaloplasty for open-angle glaucoma

Article

Number of patients/ follow up

Direction of conclusions

Reasons for non-inclusion in summary of key evidence section

Brown RH, Tsegaw S, Dhamdhere K, and Lynch MG. (2020) Viscodilation of Schlemm canal and trabeculotomy combined with cataract surgery for reducing intraocular pressure in open-angle glaucoma. Journal of cataract and refractive surgery 46(4)

n=24 people, 41 eyes

FU=4.1 months

This study found that OMNI combined with phacoemulsification

reduced intraocular pressure. The magnitude of pressure lowering with OMNI was highly correlated with the preoperative intraocular pressure.

Combined use of canaloplasty and trabeculotomy.

Davids AM, Pahlitzsch M, Boeker A, et al. (2019) Ab interno canaloplasty (ABiC)-12-month results of a new minimally invasive glaucoma surgery (MIGS).

Graefe's archive for clinical and experimental ophthalmology 257(9):1947-53

n=28 people, 36 eyes

FU=12 months

Ab interno canaloplasty effectively lowered the IOP in primary open-angle glaucoma in the short-term follow up of 12 months. A reduction of glaucoma therapy was not achieved.

Studies with more people or longer follow up were included.

Docherty G, Waldner D, Schlenker M, et al. (2020) Ab Interno Canaloplasty in Open-angle Glaucoma Patients Combined With In Vivo Trypan Blue Aqueous Venography. Journal of glaucoma 29(12):e130-e134

n=5 people

FU=up to 18 months

The primary purpose of this paper is to describe canalogram patterns observed during ab interno canaloplasty with trypan blue. There were drops in intraocular pressure and medicine use in all patients treated. There were no complications.

Studies with more people or longer follow up were included.

Gallardo MJ, Supnet RA, Ahmed IIK. (2018) Viscodilation of Schlemm's canal for the reduction of IOP via an ab-interno approach. Clinical Ophthalmology 12:2149-55

n=68 people, 75 eyes

FU=12 months

Ab interno canaloplasty was effective at reducing IOP and medicine use in eyes with uncontrolled primary open-angle glaucoma with or without cataract surgery.

Overlap with Gallardo (2021), with shorter follow up.

Gallardo MJ, Supnet RA, and Ahmed IIK. (2018) Circumferential viscodilation of Schlemm's canal for open-angle glaucoma: Ab-interno vs ab-externo canaloplasty with tensioning suture.

Clinical Ophthalmology 12:2493-2498

n=12, 12 eyes

FU=12 months

This paired eye study found ab interno canaloplasty to have comparable IOP lowering and glaucoma medicine reduction to ab externo canaloplasty in open-angle glaucoma. This suggests ab interno canaloplasty may be a suitable method for improving aqueous outflow via the trabecular pathway. Further large-scale investigation is needed.

Studies with more people or longer follow up included.

Gallardo MJ, Sarkisian SR, Vold SD, et al. (2021) Canaloplasty and trabeculotomy combined with phacoemulsification in open-angle glaucoma: Interim results from the GEMINI study.

Clinical Ophthalmology 15:481-489

n=137 people

FU=6 months

Canaloplasty followed with trabeculotomy (performed by the OMNI system) and performed concomitantly with phacoemulsification has favourable intra and perioperative safety, significantly reduces intraocular pressure and glaucoma medicines through 6 months in eyes with mild-moderate open-angle glaucoma.

Combined use of canaloplasty and trabeculotomy.

Gillmann K and Mansouri K. (2020) Minimally Invasive Glaucoma Surgery: Where Is the Evidence? Asia-Pacific journal of ophthalmology 9(3):203-14

n=4 studies

Systematic review and meta-analysis. Based on meta-analysis of 4 studies, ab interno canaloplasty reduced intraocular pressure by 36.2% and reduced glaucoma medicine use by 62.1%.

One of the studies included in the meta-analysis used ab externo canaloplasty. The other 3 studies are either described in the key evidence or appendix of this overview.

Grabska-Liberek I, Duda P, Rogowska M, et al. (2021) 12-month interim results of a prospective study of patients with mild to moderate open-angle glaucoma undergoing combined viscodilation of Schlemm's canal and collector channels and 360degree trabeculotomy as a standalone procedure or combined with cataract surgery. European Journal of Ophthalmology

n=15 people, 17 eyes

FU=12 months

Viscodilation of Schlemm's canal and collector channels paired with ab interno trabeculotomy performed with a single integrated instrument (OMNI), whether as standalone or combined with phacoemulsification, effectively lowers both IOP and the need for glaucoma medicines through 12 months of follow up.

Combined use of canaloplasty and trabeculotomy.

Habash AA, Aljindan M, Alrushoud M, et al. (2020) Combined gonioscopy-assisted transluminal trabeculotomy (GATT) with ab interno canaloplasty (ABiC) in conjunction with phacoemulsification: 12-month outcomes. Clinical Ophthalmology 14: 2491-96

n=19 people, 20 eyes

FU=12 months

The 12-month results of this study suggest that combined GATT with ab interno canaloplasty in conjunction with phacoemulsification is a safe and effective alternative in decreasing the IOP and number of glaucoma medicines in people with primary open-angle glaucoma.

Combined use of canaloplasty and trabeculotomy.

Heersink M and Dovich JA. (2019) Ab interno canaloplasty combined with trabecular bypass stenting in eyes with primary open-angle glaucoma. Clinical Ophthalmology 13:1533-42

n=86 eyes

FU=6 months

At 6 months, a greater proportion of people who had cataract extraction, trabecular meshwork bypass, and canaloplasty achieved an IOP reduction of 20% or more and an IOP of less than 18 mmHg on the same or fewer medicines than for people who had trabecular meshwork bypass and cataract extraction.

Combined use of canaloplasty and stenting.

Hirsch L, Cotliar J, Vold S, et al. (2021) Canaloplasty and trabeculotomy ab interno with the OMNI system combined with cataract surgery in open-angle glaucoma: 12-month outcomes from the ROMEO study. Journal of cataract and refractive surgery 47(7):907-15

n=81

FU=12 months

The OMNI system provided effective IOP reduction, sustained IOP control, and meaningful medicine reduction for up to 12 months postoperative.

Combined use of canaloplasty and trabeculotomy.

Kazerounian S, Zimbelmann M, Lortscher M et al. (2021) Canaloplasty ab interno (AbiC) - 2-Year-Results of a Novel Minimally Invasive Glaucoma Surgery (MIGS) Technique. Klinische Monatsblatter fur Augenheilkunde 238(10):1113-9

n=23 people, 25 eyes

FU=24 months

Ab interno canaloplasty performed independently or combined with cataract surgery seems to be a safe and effective MIGS-technique with good long-term regulation of IOP and low risk profile.

Studies with more people included.

Körber N. (2018) Ab interno canaloplasty for the treatment of glaucoma: a case series study. Spektrum der Augenheilkunde : Zeitschrift der Osterreichischen Ophthalmologischen Gesellschaft, OOG 32(6)

n=20 people, 20 eyes

FU=12 months

Findings from this study indicate that ab interno canaloplasty is comparable to conventional canaloplasty in lowering IOP and medicine dependency. Long-term follow up in a large cohort is required to confirm the efficacy of this minimally invasive glaucoma procedure

Studies with more people or longer follow up included.

Porsia L and Nicoletti M. (2020) Combined viscodilation of schlemm's canal and collector channels and 360degree ab-interno trabeculotomy for congenital glaucoma associated with sturge-weber syndrome. International Medical Case Reports Journal 13:217-20

n=1

FU=10 months

Successful treatment of glaucoma in an infant. Through 10 months of follow-up, intraocular pressure was adequately controlled without the need for adjunctive medical therapy.

Studies with more people or longer follow up included.

Pyfer MF, Gallardo M, Campbell A, et al. (2021) Suppression of diurnal (9am-4pm) IOP fluctuations with minimally invasive glaucoma surgery: An analysis of data from the prospective, multicenter, single-arm GEMINI study.

Clinical Ophthalmology 15:3931-8

n=128 people

FU=12 months

This study shows that eyes with open-angle glaucoma can benefit from an overall decreased IOP and degree of IOP fluctuations for as long as 12 months after surgical treatment with canaloplasty and trabeculotomy.

Combined use of canaloplasty and trabeculotomy.

Villa KRM, Agudelo N, Rubio B, et al. (2019) Ab interno canaloplasty after failed trabeculectomy in uncontrolled open-angle glaucoma. Investigative Ophthalmology and Visual Science 60(9)

n=7 people, 9 eyes

FU=6 months

In people with uncontrolled open-angle glaucoma after failed trabeculectomy ab interno canaloplasty appears to be a safe and effective procedure. At 6 months follow up reduction in IOP remain stable and reduction in glaucoma medicines was significantly reduced.

Conference abstract. Studies with more people or longer follow up included.

Vizzari G and Bordin P. (2018) Mid and long-term outcomes of viscodilation associated with trabeculotomy using the VISCO360 microinvasive device for the treatment of open angle glaucoma. Investigative Ophthalmology and Visual Science 59(9)

n=37 people, 55 eyes

FU=12 months

Viscodilation and trabeculotomy achieved a high percentage of surgical success during the whole follow up time and was effective in preventing the most serious immediate complications of other most invasive surgeries.

Conference abstract. Combined use of canaloplasty and trabeculotomy.

Vold SD, Williamson, BK, Hirsch L, et al. (2021) Canaloplasty and Trabeculotomy with the OMNI System in Pseudophakic Patients with Open-Angle Glaucoma: The ROMEO Study.

Ophthalmology Glaucoma 4(2):173-81

n=48

FU=12 months

The sequential combination of canaloplasty followed by trabeculotomy performed as stand-alone procedures using the OMNI system in pseudophakic patients with open-angle glaucoma provides effective IOP reduction or sustained IOP control and meaningful medicine reduction for up to 12 months postoperatively.

Combined use of canaloplasty and trabeculotomy.