How to efficiently incorporate PDT into your practice
David Callanan, MD, is a vitreoretinal specialist with Texas Retina Associates, a group practice specializing in diseases of the retina and vitreous. Dr. Callanan has been the principal investigator on numerous studies. He is currently conducting a Phase 2 trial to investigate new approaches in
wet AMD therapy. On a typical day, Dr. Callanan performs 3 to 4 PDTs and sees between 45 and 50 patients.
Mark H. Nelson, MD, MBA, is a vitreoretinal specialist in Winston-Salem, North Carolina, and the founder of RetinaNet™ Corporation, a productivity and profit-enhancing network for retinal companies. Dr. Nelson presented a poster at the May 2009 Association for Research in Vision and Ophthalmology (ARVO) annual meeting, which described the benefits of indocyanine green (ICG)-guided PDT therapy in wet AMD.
Robert Mittra, MD, is a vitreoretinal specialist and a partner with VitreoRetinal Surgery, P.A., a group
practice based in Minneapolis, Minnesota, that specializes in the medical and surgical treatment of disorders involving the retina, macula, and vitreous. He is also an Assistant Clinical Professor at the University of Minnesota and is an active member of the Macula Society, Retina Society, and the American Society of Retina Specialists, as well as an integral participant in clinical research.
Drs. Callanan, Nelson, and Mittra are consultants to Novartis Pharmaceuticals Corporation.
Please see Important Safety Information and accompanying full Prescribing Information.
Q: Why is Visudyne® (verteporfin for injection) therapy an important treatment for wet AMD?
Dr. Nelson: Simply put, there are patients who have persistent leakage, or their leakage redevelops over time. PDT with Visudyne controls the continued leakage.
Q: Why do you think this is?
Dr. Nelson: Over time, neovascular vessels mature and become enveloped with pericytes and smooth muscle. This creates a thicker vessel that becomes less dependent on VEGF. These vessels are appreciated on protein-bound ICG angiography but not on the water-soluble fluorescein angiogram.
Most physicians only measure leakage. So even though you’re keeping the leakage under control, the vessels are slowly growing and maturing as you’re treating them. If you don’t use ICG, you don’t really see the lesions that are developing. Unlike fluorescein, which is water soluble, ICG is protein bound; therefore, it images vasculature much better.
Q: How do you integrate Visudyne into your workflow without having the process become disruptive?
Dr. Nelson: The work is divided between the physician and the photographer or technician. The technician places the IV, performs the IVFA/ICG, maintains the IV line’s patency, mixes
the drug, and then supervises the infusion.* I come in after the infusion is complete, review the angiogram, and then place the laser. The technician subsequently removes the IV and completes the post-op instructions.
Dr. Callanan: At our office, both the clinic manager and photographer can start the IV.* Either one will take the patient to the PDT room—located in the back—and start the infusion. While they’re performing the infusion, I’ll continue seeing my patients as usual.
Once the patient has undergone the entire 10-minute infusion and there are about 4 minutes left to go, the technician will use the hands-free intercom system and tell me “PDT room, 4 minutes left.” This gives me enough time to excuse myself from the room, walk down the hallway, put the lens on the patient’s eye, look at the pictures, set my settings, and finally, just sit there watching the last minute tick down. Basically it takes me about 3 minutes to do a PDT.
Dr. Nelson: PDT does not affect my patient flow; it is a part of it. My staff prepares the patient by placing the IV, performing the IVFA/ICG, and then bringing the patient to the PDT room. All I do is to come in during the infusion, review the area of the angiogram that I want to treat, and then treat the patient. The staff then takes out the IV and makes sure that the post-op instructions are communicated.
Dr. Mittra: It’s actually not that disruptive. We train all of our photography technicians to perform fluorescein injections. And a few of those technicians have been trained to start the IVs for the Visudyne therapy.* I’m called in a couple of minutes before I have to use the laser. It takes about a minute before the laser and about 1½ minutes to use the laser. It’s not a huge drain on my time. Now, you do need the staff to be able to do this. If you’re running a super-tight ship in the office, you may not be able to do PDT that day, but you can certainly bring them back at a scheduled time to do it.
Q: When do you schedule PDT sessions?
Dr. Callanan: I stick them in the middle of my clinic, all week long. I’ll do 1 or 2 PDTs in the morning and 1 or 2 in the afternoon. It’s a relatively short interruption that allows me to continue seeing my other patients. If you try to schedule PDTs all on the same day, you need to plan for the intervals between infusions.
We initially tried to bring in 8 or 9 PDT patients on the same day. However, when we did this, our technicians were constantly tied up and the turnover time suffered. Each session took between 25 to 30 minutes.
Dr. Nelson: We have 2 procedure days per week, divided into 4 half-day sessions. Two sessions are dedicated to injections only. Two sessions are dedicated to PDTs. This schedule optimizes flow.
Dr. Mittra: I’m in a different office every day, so if I see somebody on Wednesday, and there’s time that day, we do it right away. If there isn’t time, or I don’t have the staff, I’ll have them come back the next week when it’s a little less busy.
Q: Do your patients have any scheduling preferences?
Dr. Callanan: When a patient learns that they’ll have to stay out of the sun for 5 days, they sometimes ask to reschedule. Some patients have to attend an important outdoor event or have another doctor’s appointment later in the day. In such cases, we can wait a few more days to schedule the appointment.
Dr. Mittra: Many of these patients are nonemergent because they are already subfoveal. We aim to treat patients within several days. Historically, when standard laser was the mainstay of treatment, it was more critical to see patients with CNVM immediately because if juxtafoveal lesions became subfoveal, the window for intervention could have been lost. All subfoveal cases can now be performed within a week or 2.
Dr. Nelson: If you are going to have any control over your practice, you have to standardize your treatments. However, patients still demand some flexibility. They have two different days to choose from, one in the morning and one in the afternoon.
Q: How large is the room in which you store the PDT equipment?
Dr. Callanan: No bigger than a large closet. It houses the PDT machine, the lamp and chair, and one extra chair for the patient’s family member.
Dr. Nelson: We perform PDTs in a 10 x 10 room that also houses an argon and krypton laser.
Q: How many assistants do you need when administering PDT?
Dr. Callanan: Two technicians are more than enough. When one technician is busy, the other will come in and start the IV. There is only one technician involved in the PDT at any given time. The patient is then medically monitored during the infusion.
Dr. Nelson: A technician, who assists with the procedure; and a photographer, who replaces the IV and performs the IVFA/ICG.
Q: Do you have any tips for your fellow eyecare professionals on how best to integrate Visudyne into their practice?
Dr. Callanan: Sure. Make sure that you have the laser in a convenient location.
Initially, you should administer PDTs at the end of morning and afternoon clinics until you have an efficient routine. Have the patient arrive 45 minutes before the conclusion of that day’s clinic. Now, some physicians obviously work through lunch, in which case I’d recommend that they schedule the PDT session at a time when they won’t feel rushed.
Also, use a phone-based intercom system. Instead of a technician having to leave a patient and search for me throughout the office, he or she can simply pick up a phone and do an “all-page.” That way, the technician doesn’t have to track me down. Every phone in our office is linked to the intercom. It’s soft enough so that it’s not disruptive and it’s really efficient, because everybody can stay where they are and continue what they are doing.
Finally, physicians reintegrating Visudyne into the office setting should give themselves a full 5 minutes prior to administering the laser. The physician may want to get comfortable with the settings, have time to study the photos, and make sure that the lens is positioned properly. Of course, most physicians have probably done PDT in the past and are pretty good at it. So, with time and experience, they should become more proficient in the process.
Dr. Nelson: The most important tip for effective patient flow is to have days dedicated to procedures. This gives the physician full control over the schedule since patients with common diagnoses are treated with similar resources in a repetitive manner. Patients also prefer the ability
to schedule the PDT on a day that better meets their needs as they are going to have to stay out of the sun for 5 days. The only disadvantage is that patients need to return on a separate day.
In terms of clinical practice, I utilize ICG videoangiography to visualize these neovascular vessels and it allows me to localize the PDT treatment to 1-2 millimeters. While I believe that this provides an extra degree of clinical advantage, it does take additional time. I frequently review the previous angiograms prior to the patient’s visit. With time and experience, the process has become increasingly efficient for me.
* You are responsible for understanding the laws of your state regarding IV administration. Novartis Pharmaceuticals Corporation cannot make recommendations regarding who is qualified to give a Visudyne infusion.
Indication
Visudyne® is indicated for the treatment of predominantly classic subfoveal choroidal neovascularization due to age-related macular degeneration, pathologic myopia or presumed ocular histoplasmosis.
Important Safety Information
Visudyne is contraindicated for patients with porphyria or known hypersensitivity to any component of Visudyne.
Infusion-related transient back pain occurred with Visudyne only. Verteporfin infusion induces temporary photosensitivity; patients should avoid exposure of skin and eyes to direct sunlight or bright indoor light for 5 days. To prevent extravasation, avoid fragile hand veins in favor of larger antecubital veins.
Severe vision decrease (≥ 4 lines) was reported within 7 days in 1% to 5% of patients. Partial
recovery occurs in some patients. Do not re-treat these patients until vision completely recovers to
pretreatment levels and potential benefits and risks of subsequent treatment are carefully weighed.
The most frequently reported adverse events (10%-30% incidence) were injection site reactions (including extravasation and rashes), blurred vision, decreased visual acuity, and visual field defects.
Please see accompanying full Prescribing Information.
