We hope everyone is having a wonderful holiday season. We had the opportunity to catch up with the Cole Eye Institute Argus II team, led by Aleksandra Rachitskaya, Meghan DeBenedictis, and Alex Yuan. In today’s post, Dr. Rachitskaya and her team share with us many pearls to optimize outcomes in patients undergoing Argus II implantation.
Aleksandra Rachitskaya, MD
Vitreoretinal Surgeon
Cole Eye Institute, Cleveland Clinic
Meghan DeBenedictis, MS, LGC
Genetic Counselor
Cole Eye Institute, Cleveland Clinic
Alex Yuan, MD, PhD
Vitreoretinal Surgeon
Cole Eye Institute, Cleveland Clinic
Argus II Retinal Prosthesis (Second Sight, Sylmar, CA) is gaining popularity with over 250 implantations performed worldwide. Below are some pearls one should keep in mind when considering the development of an Argus II program.
PATIENTS
Argus II is currently FDA approved in the United States for patients with a clinical diagnosis of retinitis pigmentosa (RP). Genetic testing is not required in order to be considered a candidate. The patients’ visual acuity needs to be bare light perception or worse, but must have had functional vision in the past. On average, patients who have RP that is advanced enough to qualify for the implant tend to be older. The youngest permitted age for implantation is 25 years old. Given the fact that the number of patients who qualify is relatively small, it is advisable for an implanting surgeon to be involved in managing patients with inherited retinal diseases or collaborate with a retinal dystrophy specialist.
Psychosocial assessment of a potential surgical candidate is critical. Given the cost of the implant and the time/labor investment, the physician and the patient should be aligned in regards to expectations. The patient should be able to reiterate the limitations of the device, the visual stimulation and function that Argus is able to provide, and agree to participate and complete the essential rigorous rehabilitation process.
The Argus II patient populations oftentimes depend on others for many activities of daily living, including transportation. Thus, it is imperative to assess the support structure of family/friends and ensure willingness and ability to accompany the patient to the required visits and to aid the patient in post-operative care and visual rehabilitation at home. It is advisable for patients to have prior low vision training and orientation and mobility skills. Consultation with a psychiatrist or psychologist may be helpful if the candidate suffers from clinical depression, which is common in patients with end-stage retinal dystrophies
The patients who benefit the most from Argus II are those who are actively engaged with their environment, motivated to try new technologies, have a strong support system, and who have documented the desire for independence despite their visual impairment.
SURGERY
Anatomically, ideal candidates should have no ocular co-morbidities other than RP and no other prior surgeries besides cataract extraction. Intact conjunctiva and rectus muscles are important to optimize the extraocular placement and prevent conjunctival erosion. Patients can be pseudophakic or aphakic. Phakic patients are rendered aphakic during Argus II implantation. The axial length must be between 20.5 and 26.0 mm due to constraints set by the length of the cable connecting the electronics case to the array. Minimizing the array-retina distance translates into lower electrode activation thresholds and pre-operative OCT imaging helps to ensure normal macular contour. Additionally, given the fact that Argus II works by electrically stimulating the inner retina, it is necessary for the inner retina, optic nerve and visual pathways to be intact.
Argus II implantation surgery is significantly longer than an average vitreoretinal surgery and requires general anesthesia, intraoperative antibiotics, steroids, and Foley placement. Medical clearance and communication with the anesthesiologist ensures patient safety. Given the cost of the implant, it is advisable to have a dedicated operating room team handling the implant. The use of such technologies as intraoperative OCT might aid in Argus II implantation.
POST-IMPLANTATION REHABILITATION
Post-implantation visual rehabilitation can be performed by trained low vision specialists, occupational therapists, and/or orientation and mobility specialists. The visual rehabilitation process teaches the Argus II recipients how to use the system. It provides techniques on head scanning, object localization and identification, and mobility performance. It also offers instructions for home and occupational rehabilitation.
BILLING
Although Argus II has been approved by the FDA since 2013, regional coverage is determined by Medicare Administrative Contractors (MACs). Currently local coverage determinations (LCDs) are not present in all MAC jurisdictions. Medicare will cover the cost of the device, surgery, and programming in states with LCDs. It is recommended to have a dedicated billing specialist to obtain any required pre-authorizations before proceeding with surgery. Letters of medical necessity may be required to be written and provided by the surgeon.
TEAM
Argus II is definitely a team sport. At the Cole Eye Institute, the Argus II coordinator screens patients over the phone to ensure potential candidate eligibility. The initial evaluation by physicians requires patient and family participation and includes extensive discussion of the expectations, risks, benefits, and limitations. The retinal dystrophy specialist is available to confirm the diagnosis of RP. Imaging including fundus photography, SD-OCT, and a- and b-scan ultrasonography are performed.
In select cases, evaluation by a psychiatrist or psychologist may be recommended also. Some patients are asked to obtain orientation and mobility skills before proceeding with Argus II implantation. This helps to evaluate the patient’s motivation and ability to learn new tasks.
Before surgery, the billing team aids in ensuring insurance coverage. Additionally, low vision rehabilitation services discuss the coverage of the rehabilitation program with a potential patient.
After pre-op medical clearance, the patient is scheduled for surgery. It is anticipated that the surgery will take about 3-5 hours. Intra-operative OCT is routinely performed during implantation to aid in array placement. Post-surgical visits are scheduled for post-operative days 1, 7, 14, and 30.
Device programing and activation is performed 1 month after the surgery followed by Argus II visual rehabilitation. On-going communication continues among the physicians, the rehab specialists and the patient to track the patient’s progress. Scheduled visits occur at 3, 6, 12 months and then annually.
In summary, implementation of a successful Argus II program requires a significant investment of resources and building a dedicated team. As we celebrate the holiday season and reflect on the past year, we realize the difference Argus II makes for our patients. Completely blind before, Argus II recipients are able to tell if their family members are around them at holiday gatherings. Moreover, multiple patients describe seeing the flickering of candlelights in church and the Christmas tree lights. To hear these stories is the best holiday gift!
