Gonioscopy-Assisted Transluminal Trabeculotomy, Ab Interno Trabeculotomy: Technique Report and Preliminary Results

doi:10.1016/j.ophtha.2013.11.001

Ophthalmology

Volume 121, Issue 4, April 2014, Pages 855-861

Presented at: American Academy of Ophthalmology Annual Meeting, November 2013, New Orleans, LA.

https://doi.org/10.1016/j.ophtha.2013.11.001 Get rights and content

Purpose

To introduce a minimally invasive, ab interno approach to a circumferential 360-degree trabeculotomy and to report the preliminary results.

Design

Retrospective, noncomparative cases series.

Participants

Eighty-five eyes of 85 consecutive patients who sought treatment at Glaucoma Associates of Texas with uncontrolled open-angle glaucoma and underwent gonioscopy-assisted transluminal trabeculotomy (GATT) for whom there was at least 6 months of follow-up data.

Methods

Retrospective chart review of patients who underwent GATT by 4 of the authors (D.S.G., D.G.G., O.S., R.L.F.) between October 2011 and October 2012. The surgery was performed in adults with various open-angle glaucomas.

Main Outcome Measures

Intraocular pressure (IOP), glaucoma medications, visual acuity, and intraoperative as well as postoperative complications.

Results

Eighty-five patients with an age range of 24 to 88 years underwent GATT with at least 6 months of follow-up. In 57 patients with primary open-angle glaucoma, the IOP decreased by 7.7 mmHg (standard deviation [SD], 6.2 mm Hg; 30.0% [SD, 22.7%]) with an average decrease in glaucoma medications of 0.9 (SD, 1.3) at 6 months. In this group, the IOP decreased by 11.1 mmHg (SD, 6.1 mmHg; 39.8% [SD, 16.0%]) with 1.1 fewer glaucoma medications at 12 months. In the secondary glaucoma group of 28 patients, IOP decreased by 17.2 mmHg (SD, 10.8 mmHg; 52.7% [SD, 15.8%]) with an average of 2.2 fewer glaucoma medications at 6 months. In this group, the IOP decreased by 19.9 mmHg (SD, 10.2 mmHg; 56.8% [SD, 17.4%]) with an average of 1.9 fewer medications (SD, 2.1) at 12 months. Treatment was considered to have failed in 9% (8/85) of patients because of the need for further glaucoma surgery. The cumulative proportion of failure at 1 year ranged from 0.1 to 0.32, depending on the group. Lens status or concurrent cataract surgery did not have a statistically significant effect on IOP in eyes that underwent GATT at either 6 or 12 months (P > 0.35). The most common complication was transient hyphema, seen in 30% of patients at the 1-week visit.

Conclusions

The preliminary results and safety profile for GATT, a minimally invasive circumferential trabeculotomy, are promising and at least equivalent to previously published results for ab externo trabeculotomy.

Section snippets

Methods

A retrospective chart review was performed for all patients who underwent GATT by 4 of the authors (D.S.G., D.G.G., R.L.F., O.S.) at Glaucoma Associates of Texas between October 2011 and October 2012. The study followed the tenets of the Declaration of Helsinki and was approved by the affiliated hospital's institutional review board. Written consent was obtained from all patients before surgery.

All patients underwent a preoperative gonioscopic examination that revealed an open angle and

Results

Table 1 describes the study groups, including number of eyes per group, mean age, gender, and distributions of diagnoses per group. Efficacy data are reported in Table 2 for 85 eyes of 85 patients. On average, the patients with open-angle glaucoma (study groups 1–3) showed a mean decrease in IOP of 7.7 mmHg (standard deviation [SD], 6.2 mmHg) at 6 months (P < 0.001) and of 11.1 mmHg (SD, 6.1 mmHg) at 12 months (P < 0.001). The average percent lowering of IOP in groups 1 through 3 was 30.0% (SD,

Discussion

Over the past decade, the indications for circumferential trabeculotomy have widened to encompass adult glaucomas.11, 12, 13 This is because of the desire to reduce complications from filtration surgery, particularly bleb-related issues, and instead to try to salvage the natural outflow channels of the eye. In addition, over the past decade, there has been a major surge in interest and innovation for angle-based procedures in the treatment of open-angle glaucoma, exemplified by Trabectome

Acknowledgment

The authors thank Alexandra B. Hernandez of Gory Details Illustration for Figure 1.

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: Financial Disclosure(s): The author(s) have no proprietary or commercial interest in any materials discussed in this article.

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Original articleGonioscopy-Assisted Transluminal Trabeculotomy, Ab Interno Trabeculotomy: Technique Report and Preliminary Results

Purpose

Design

Participants

Methods

Main Outcome Measures

Results

Conclusions

Section snippets

Methods

Results

Discussion

Acknowledgment

Ophthalmology

J AAPOS

J AAPOS

J Cataract Refract Surg

Am J Ophthalmol

Am J Ophthalmol

Epicritical consideration of 300 cases of trabeculotomy ‘ab externo’

Trans Ophthalmol Soc U K

Congenital glaucoma before and after the introduction of microsurgery: results of ‘macrosurgery’ 1943–1963 and of microsurgery (trabeculotomy/ectomy) 1970–1974

Acta Ophthalmol (Copenhn)

Principles and problems of therapy in congenital glaucoma

Invest Ophthalmol Vis Sci

A new technique for opening the canal of Schlemm: preliminary report

Br J Ophthalmol

360 degrees trabeculotomy for primary congenital glaucoma

Arch Ophthalmol

Original article
Gonioscopy-Assisted Transluminal Trabeculotomy, Ab Interno Trabeculotomy: Technique Report and Preliminary Results