title: Scanning Electron Microscopy Evaluation of an EX-PRESS Mini Glaucoma Shunt After Explantation.
abstract: We report a case of an explanted stainless steel miniature glaucoma drainage device (EX-PRESS) implanted under a scleral flap for pseudoexfoliation open-angle glaucoma surgical treatment. The glaucoma shunt was implanted in a 75-year-old white man with medically refractive glaucoma. Cataract surgery was performed simultaneously. After 2 years, the shunt extruded through the scleral flap and the conjunctiva and it was, therefore, explanted. Scanning electron microscopy images of the EX-PRESS mini glaucoma shunt were acquired to verify the patency of the device lumen and the presence of fibrosis or cellular adhesion on the device. Energy dispersive spectroscopy for chemical surface characterization of the EX-PRESS shunt was performed. Scanning electron microscopy-acquired images showed minimal extracellular material proliferation on the lumen device. The energy dispersive spectroscopy analysis revealed a high peak of carbon suggesting the organic nature of the residuals found on the shunt lumen. The surface showed few superficial pits, likely due to an initial corrosion process.
authors.affiliation: *Eye Clinic †Department of Medical Science, University of Trieste, Trieste, Italy.
authors.forename: Daniele
authors.initials: D
authors.lastname: Tognetto
authors.forename: Paolo
authors.initials: P
authors.lastname: Cecchini
authors.forename: Rossella
authors.initials: R
authors.lastname: D'Aloisio
authors.forename: Odilla
authors.initials: O
authors.lastname: Vattovani
authors.forename: Gianluca
authors.initials: G
authors.lastname: Turco
mesh_terms: D000368:Aged; D000867:Anterior Chamber / Q000648:ultrastructure*; D020878:Device Removal / Q000379:methods*; D005109:Extracellular Matrix / Q000648:ultrastructure*; D020327:Glaucoma Drainage Implants / Q000009:adverse effects*; D005902:Glaucoma, Open-Angle / Q000175:diagnosis / Q000503:physiopathology / Q000601:surgery*; D006801:Humans; D007429:Intraocular Pressure / Q000502:physiology*; D008297:Male; D008855:Microscopy, Electron, Scanning / Q000379:methods*; D011475:Prosthesis Failure