title: Short- and long-term effects on the ciliary body and the aqueous outflow pathways of high-intensity focused ultrasound cyclocoagulation.
abstract: Several physical methods can be used to coagulate the ciliary body and decrease intra-ocular pressure in patients with glaucoma. The study described here investigated the short- and long-term effects of high-intensity focused ultrasound (HIFU) cyclocoagulation on the aqueous humor production structures and outflow pathways. Thirty-four rabbit eyes were sonicated with a ring-shaped probe containing six miniaturized HIFU transducers. Light, scanning electron and transmission electron microscopy and corrosion casts were performed. In the affected regions, the epithelium of the ciliary processes was degenerated or necrotic and sloughed off. Examinations performed several months afterward revealed involution of the ciliary processes. Vascular corrosion cast revealed focal interruption of the ciliary body microvasculature. In most animals, a sustained fluid space was seen between the sclera, the ciliary body and the choroid, likely indicating an increase in the aqueous outflow by the uveoscleral pathway. These results suggest that HIFU cyclocoagulation has a dual effect on aqueous humor dynamics.
authors.affiliation: University Hospital of Grenoble, Grenoble, France; Université Grenoble Alpes, Grenoble, France. Electronic address: faptel@chu-grenoble.fr.
authors.forename: Florent
authors.initials: F
authors.lastname: Aptel
authors.affiliation: EyeTechCare, Rillieux la Pape, France.
authors.forename: Aurélie
authors.initials: A
authors.lastname: Béglé
authors.affiliation: EyeTechCare, Rillieux la Pape, France; Inserm, U1032, Lyon, F-69003, France; Université de Lyon, Lyon, France.
authors.forename: Arash
authors.initials: A
authors.lastname: Razavi
authors.affiliation: EyeTechCare, Rillieux la Pape, France.
authors.forename: Fabrice
authors.initials: F
authors.lastname: Romano
authors.affiliation: EyeTechCare, Rillieux la Pape, France.
authors.forename: Thomas
authors.initials: T
authors.lastname: Charrel
authors.affiliation: Inserm, U1032, Lyon, F-69003, France; Université de Lyon, Lyon, France.
authors.forename: Jean-Yves
authors.initials: JY
authors.lastname: Chapelon
authors.affiliation: Hospices Civils de Lyon, Lyon, France.
authors.forename: Philippe
authors.initials: P
authors.lastname: Denis
authors.affiliation: Inserm, U1032, Lyon, F-69003, France; Université de Lyon, Lyon, France.
authors.forename: Cyril
authors.initials: C
authors.lastname: Lafon
mesh_terms: D000818:Animals; D001082:Aqueous Humor / Q000000981:diagnostic imaging*; D002924:Ciliary Body / Q000000981:diagnostic imaging*; D005260:Female; D005500:Follow-Up Studies; D057086:High-Intensity Focused Ultrasound Ablation / Q000379:methods*; D008855:Microscopy, Electron, Scanning / Q000379:methods; D017348:Microscopy, Electron, Scanning Transmission / Q000379:methods; D023421:Models, Animal; D011817:Rabbits; D014463:Ultrasonography
keywords: Aqueous outflow; Ciliary body; Corrosion cast; Glaucoma; High-intensity focused ultrasound; Histopathology; Intravascular latex injection; Scanning electron microscopy