Monocentric prospective study conducted in two phases evaluating the secretion and elimination of aqueous humor by fluorophotometry in patients with glaucoma treated with cyclo-coagulation with ultrasound.

Population selected:

- Patients with refractory open angle glaucoma despite previous treatments currently validated for glaucoma.

The purpose of our study is:

- To evaluate the mechanism of action of glaucoma treatment by cyclo-coagulation with high intensity focused ultrasound in studying the secretion and elimination of aqueous humor by fluorophotometry.

Planning:

• First phase: 2 patients (feasibility study) If reduction of at least 10% of the flow of aqueous humor production at one month in the first two patients in the feasibility study, further in second phase.
• Second phase: 6 patients

Main outcome criteria:

Reduction of aqueous humor flow at 6 months compared with the pretreatment of aqueous humor flow.

Inclusion Criteria:

• refractory primary open-angle glaucoma (POAG)
• IOP> 21 mm Hg and <32 mm Hg with an optimal treatment.
• Lack of history of cyclo-destruction of the ciliary body (laser diode, cold ...)
• Lack of intraocular surgery or laser therapy in the eye seen in the three months preceding the date of HIFU treatment.
• Male or female age (s) of at least 18 and able to give informed consent
• Patient who signed the informed consent form
• Patient affiliated to a social security scheme

Exclusion Criteria:

• History of glaucoma by placing a drainage implant (valves, pipes ...)
• previous refractive procedures preventing accurate measurement of intraocular pressure (PRK, LASIK)
• General treatment which may alter IOP began in the month before the HIFU procedure
• Patient monophthalmus
• thyroid orbitopathy
• History of ocular or retrobulbar tumor
• Cyclodialysis
• choroidal hematoma or uprising choroidal
• Anatomy of the eyeball inadequate treatment or medical device (eye too small or too large)
• Pregnancy, breastfeeding, lack of contraceptive use among women at risk of having a child
• Participation in another clinical investigation of a medical or surgical treatment can affect the intraocular pressure in the three months preceding the HIFU
• Patient minor or major protected by law