Macroscopic analysis of filtering bleb functionality after XEN Gel Stent implantation with Anterior Segment Optical Coherence Tomography

Purpose The new approach of Micro invasive Glaucoma Surgery, XEN Gel Stent is made of soft collagen and it is introduced by a corneal incision, trough the anterior chamber angle and it stands under the conjunctiva space. To study the bleb macroscopic morphology with Anterior Segment Optical Coherence Tomography and correlate it with the clinical evaluation. Methods Prospective case‐control study with 10 eyes of 8 patients with the range follow‐up to 6 months after XEN Gel Stent implantation. Two groups were characterized according to the clinical evaluation (Intraocular Pressure, topical treatment or additional procedures, as YAG‐LASER and Needling). Group 1 describes those patients with IOP under 21 mmHg without topical treatment even if it was necessary an additional YAG‐LASER or needling ( n = 8). Group 2 was formed with IOP above 21 mmHg or under 21 mmHg with topical treatment ( n = 2). The parameters analyzed were the bleb structure (diffuse or cystic), extension (height, width and length), chamber angle aperture and tube extension (anterior chamber and scleral). Results The group 1 appears to be with indifferently diffuse or cystic higher extensions of filtering blebs than those in group 2. The structural analysis with OCT was concordant with the macroscopic morphology in slit lamp evaluation. The tube extension in anterior chamber and under conjunctiva and its chamber angle entrance was relatively variable over all patients. Conclusions The clinical assessment of the filtering bleb has proved a significant concordance with the filtering bleb macroscopic morphology in the AS‐OCT. Additional longitudinal studies about this topic will be necessary to improve the knowledge and the surgeon's management capabilities.