The overall goal of surgical protocol is to demonstrate a novel non-incisional surgical procedure that reduces intraocular pressure in glaucoma patients. The procedure determines the selective coagulation of the ciliary body by means of high intensity ultrasound beams while sparing the agent's structures. The technique is a safer, faster and less invasive, compared to traditional cycle destructive procedure, with more predictable results and less complications.
A crucial step of the procedure is the proper centering of the probe without moving, rotating or pushing it during the entire treatment. Begin preparing the treatment device by entering data about the surgeon and patient using the control unit touch screen then select the eye to treat. Next, open the sterile single-use device pack containing the coupling cone and the treatment probe and connect their cables to the control unit.
Disinfect the palpebral and periorbital skin with 10%povidone iodine 3x. Wipe the disinfected skin with clean sterile gauzes. Put a sterile surgical drape over the face of the patient with the central hole centered over the eye under treatment in order to properly expose it.
Next, place the patient's head slightly backwards in order to put the ocular surface horizontally allowing a comfortable placement of the cone of the device. Then, open the patient's eye without using the speculum. Put the coupling cone over the ocular surface with tubing on the temporal side and gently move it to correctly position and center it forming a uniform white scleral ring surrounding the limbus.
Push the aspiration button on the foot switch to start a low level suction from the peripheral ring of the coupling cone until the vertical bar on the screen becomes green. Next, insert the treatment probe inside the coupling cone with the cable in nasal position. Fill the empty space delimited by the eye, the cone and the probe with sterile balanced salt solution, or BSS, at room temperature at the beginning and during the entire procedure to allow good propagation of the therapeutic ultrasounds.
Refill at the appropriate level in case of BSS leakage. Next, ask the patient to hold the position and keep the head perfectly still then push the start button on the foot switch to start the treatment and hold the pressure during all the procedure. Firmly maintain the optimal position of the probe in the coupling cone during the entire procedure.
Avoid moving, rotating or pushing the probe in order to permit the best centering of therapeutic ultrasound beams during the treatment. At the end of the procedure, deactivate the suction system by pressing the aspiration button on the foot switch and slowly tilt the cone until BSS is removed through the tube. Finally, after surgery, instill antibiotic plus steroid drops in the treated eye immediately after the procedure and patch the treated eye for 24 hours.
Results indicate that the mean intraocular pressure, or IOP value, decreased compared to the preoperative value at each postoperative visit. Specifically, there was also a mean reduction of hypotensive eyedrops and oral acetozolamide tablets numbers over time. The procedure determines a significant reduction of intraocular pressure as well as the need for hypotensive eye drops or tablets.
The treatment is completely automated and standardized, lasts less than three minutes, and can be performed under locational anesthesia in outpatient setting. The procedure represent a step forward in the surgical treatment of glaucoma and provide ophthalmologist with a new minimally invasive option in the current therapy armamentarium. Future developments in the field of Sound Cyclo Plasty could allow treatments in term of ultrasound exposure with time in order to best allow treatment to each patients and eye.
