In vivo confocal microscopy: qualitative investigation of the conjunctival and corneal surface in open angle glaucomatous patients undergoing the XEN-Gel implant, trabeculectomy or medical therapy

Stefano Baiocchi; Cosimo Mazzotta; Arianna Sgheri; Alessandro Di Maggio; Simone Alex Bagaglia; Matteo Posarelli; Leonardo Ciompi; Alessandro Meduri; Gian Marco Tosi

doi:10.1186/s40662-020-00181-8

In vivo confocal microscopy: qualitative investigation of the conjunctival and corneal surface in open angle glaucomatous patients undergoing the XEN-Gel implant, trabeculectomy or medical therapy

Eye Vis (Lond). 2020 Mar 10:7:15. doi: 10.1186/s40662-020-00181-8. eCollection 2020.

Authors

Stefano Baiocchi¹, Cosimo Mazzotta¹, Arianna Sgheri¹, Alessandro Di Maggio¹, Simone Alex Bagaglia¹, Matteo Posarelli¹, Leonardo Ciompi¹, Alessandro Meduri², Gian Marco Tosi¹

Affiliations

¹ 1Department of Medicine, Surgery and Neurosciences, Ophthalmology Unit, Policlinico Santa Maria alle Scotte, University of Siena, Viale Bracci 8, ZIP code 53100 Siena, Italy.
² 2Ophthalmology Unit, Department of Biomedical Sciences, University of Messina, Messina, Italy.

Abstract

Purpose: Assessing the quality of the ocular surface by in vivo scanning laser confocal microscopy (IVCM) in primary open angle glaucoma (POAG) patients treated by Xen 45 Gel Stent, medical therapy and trabeculectomy.

Methods: Retrospective, single-center, single-masked, comparative study including 60 eyes of 30 patients (mean age 61.16 ± 10 years) affected by POAG. Eyes were divided into 3 groups: Group 1 eyes underwent the Xen 45 Gel Stent procedure, Group 2 eyes were under medical therapy, Group 3 eyes were surgically treated by trabeculectomy. All patients underwent HRT II IVCM analysis of cornea, limbus, conjunctiva, sub-tenionian space and sclera.

Results: The Xen 45 Gel stent, if properly positioned in the sub-conjunctival space preserves goblet cells and limits ocular surface inflammation. Regular corneal epithelial cells with micro-cysts, and normo-reflective sub-epithelial nerve plexus are documented by IVCM. In sub Tenon's implants an alternative lamellar intra-scleral filtration is detectable. Combined surgical procedures show a noticeable number of inflammatory cells with rare micro-cysts. Post-trabeculectomy inflammatory reaction is more evident than Xen 45 Gel Stent associated surgical procedures, but less than medical therapy where a conspicuous presence of Langerhans cells, peri-neural infiltrates, marked loss of goblet cells and fibrosis is visible.

Conclusion: Ocular surface inflammation was more notable in topical therapy than after trabeculectomy, which itself causes more inflammation than XEN Gel stents.

Keywords: Confocal microscopy; Glaucoma; IVCM; Inflammation; MIGS; Ocular surface; POAG; Primary open angle glaucoma; Xen 45 gel stent.