New tools set to revolutionise glaucoma treatment
Microsensors release medications in response to IOP spikes in real time
Within a few years miniature tools will be available that continuously monitor intraocular pressure and release medications in response to IOP spikes in real time, revolutionising glaucoma diagnosis and treatment. These devices eventually will be delivered through a needle at the slit lamp, said Marlene R Moster MD in the American Glaucoma Society Subspecialty Day Lecture at the AAO 2018 Annual Meeting in Chicago.
A device small enough to be implanted in the anterior chamber of a mouse already has been tested, Dr Moster said. It could be attached to a depot of medication dispensed with a 100-nanometer micro pump in a 3x6mm implantable device.
Existing human devices include a 11.3mm in diameter and 0.9mm thick implanted through a 5.5mm incision device in the ciliary sulcus in six patients in the ARGOS-01 trial. It is charged and data transferred via a hand-held reader unit that the patient brings close to the face for a few minutes several times a week. In a study with six patients, the device generated IOP readings mostly comparable to Goldmann applanation tonometry, but patients developed inflammation, angle narrowing, pigment dispersion and pupil distortion (Koutsonas A et al. Invest Ophthalmol Vis Sci 2015; 56(2):1063-9).
A thinner version developed for ARGOS-02 inserted through a 3.2mm incision in 22 patients generated more consistent data without these adverse effects, making 24-hour pressure monitoring possible, Dr Moster noted. It is now CE marked in Europe and marketed as the Eyemate-IO (Implandata).
An even smaller device measuring 0.6×1.2×0.5mm being tested in dogs will be rechargeable via a device placed at the patient’s bedside. Moster believes designs that remove the need for proactive patient involvement will be essential for successful devices.