Modern Glaucoma Management

American Academy of Ophthalmology 2012

Douglas J. Rhee, MD; Shuchi B. Patel, MD


November 21, 2012

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Gonioscopy, Resurrected

Douglas J. Rhee, MD: Hello. I'm Dr. Douglas Rhee, Associate Professor of Ophthalmology at Harvard Medical School in Boston. Welcome to Medscape Ophthalmology Insights. Joining me is Dr. Shuchi Patel, Assistant Professor and Director of the Glaucoma Service at Loyola University in Chicago. We are here today at the American Academy of Ophthalmology (AAO) meeting in Chicago to discuss the latest developments in glaucoma. Dr. Patel, welcome to Medscape.

Shuchi B. Patel, MD: Thank you. I'm happy to be here.

Dr. Rhee: We just came off of a great Glaucoma Subspecialty Day sponsored by the American Glaucoma Society, and some of the highlights were low-tension glaucoma, acute angle closure, microincision glaucoma surgery (MIGS), and some of the newer surgical procedures. What do you think has been hot at the meeting so far?

Dr. Patel: This meeting was great because there were so many topics that were very clinically applicable, especially one topic that you mentioned -- acute angle closure. They brought up the importance of gonioscopy and being able to do gonioscopy and interpret your findings. That was a really important point.

Dr. Rhee: We have been doing gonioscopy. We learned as residents, and we have been doing it for years, ever since we stopped training. Why do you think there has been such a resurgence of interest in gonioscopy?

Dr. Patel: The resurgence has been because of the new angle-based surgeries that are developing. It's important with surgeries such as Trabectome® (NeoMedix Corp.; Tustin, California) or the iStent® (Glaukos; Laguna Hills, California) to be able to do gonioscopy and to interpret the findings so that it is used diagnostically as well as during the surgical procedure itself.

Dr. Rhee: Yes, those ab interno procedures rely on doing good intraoperative gonioscopy. We are going to touch on that in a moment, but let's talk about gonioscopy in the clinic. First of all, do you have any recommendations on where clinicians who aren't residents or trainees can get more information on how to get better trained? Is there a good resource that you are aware of that you could share with us?

Dr. Patel: Sure. We can look up information about gonioscopy in books, but a great resource that is available is the Website that was created by Dr. Lee Alward. There are dynamic movies about gonioscopy as well as pictures that cover many diagnostics. It's a great Website, a great resource.

Dr. Rhee: There are a lot of great techniques there. The University of Iowa team is to be credited with that Website.

Fitting Gonioscopy Into Your Routine

What are the barriers for doing regular gonioscopy? In a busy practice, it is not often included in the protocol. We are so dependent on our support staff to gather information. What tips do you have for our readers in terms of how you incorporate gonioscopy into your practice, and when do you do gonioscopy on patients?

Dr. Patel: That's a good point. Sometimes it just gets overlooked or forgotten, and then if a patient is already dilated, it is postponed for another visit. A good way to incorporate it into your practice so that it's not forgotten or missed is to make sure that every new patient gets gonioscopy at least once when they come into the clinic. Before any dilation, the gonioscopy is done. I like to do gonioscopy at least once a year on every patient who is phakic because there can be changes, and in my pseudophakic patients, at least once when they are a new patient or after they are newly pseudophakic. If a patient has cataract surgery, I repeat the gonioscopy at least once afterwards.

Dr. Rhee: That's a great idea. Can you walk us through a sample protocol of how a patient comes through your office?

Dr. Patel: For us, any new patient will get the standard history, vision, and pressure. It's important to check pressure before gonioscopy because the pressure can change with gonioscopy, especially if you are doing indentation gonioscopy, which you should be doing. Refraction should also be done before gonioscopy. All patients get those standard workups, and then the physician will go in and do a gonioscopy and continue the examination, including the dilation.

Dr. Rhee: So, they will do the gonioscopy before dilation and then proceed if it's safe to dilate the patient?

Dr. Patel: Exactly.

Dr. Rhee: Thank you for sharing your office protocol with us.

The iStent: What Do the Data Say?

Let's touch on the new surgical implant devices. The latest thing that has happened since the last AAO meeting was approval of the iStent. We have had Trabectome. What do you think about that product and that procedure?

Dr. Patel: Any time a new glaucoma procedure or instrument is available, it's very exciting, because we have been focusing on trabeculectomy and blood-based surgeries for many years.

Dr. Rhee: What do you think of the data? Some have been published. Can you share with our readers what you know about the data?

Dr. Patel: The Glaukos iStent was approved to be performed in conjunction with cataract surgery, and the data show that you achieve a moderate reduction in pressure with cataract surgery at 1 year compared with cataract surgery alone, but by 2 years there is no difference in pressure between cataract surgery alone and cataract surgery with the implantation of a single stent.

Dr. Rhee: We have heard about the experiences of our colleagues outside of the United States with putting in multiple implants, but that is not the way it was approved in the United States. How do you think you might incorporate the iStent into your practice, if at all? Where do you think it fits? Maybe that's not a fair question. Rather than asking you where you think you are going to incorporate it into your practice, where do you think it might have a role in our overall armamentarium?

Dr. Patel: It's a moderate reduction in pressure. For patients who need a small reduction in pressure or are on maximal medical therapy and need a little extra push temporarily until they become a steroid responder, or in a temporary situation where they may need a reduction in pressure and they are already having cataract surgery, it might be a nice addition to the armamentarium, especially for a comprehensive ophthalmologist or a glaucoma specialist because of the reported simplicity of the procedure.

Do I Need a Femtosecond Laser?

Dr. Rhee: Do you think the femtosecond laser might have a role in the management of glaucoma patients concurrent with cataract and glaucoma surgery? What are your thoughts about femto?

Dr. Patel: The femtosecond laser has been the new and upcoming technology. When you take into account the time that is added to the procedure as well as the cost of the procedure, it has to provide a significant benefit to the patient as well as to the physician who is purchasing this equipment. For a standard cataract surgeon, the benefits may be minimal except for certain situations. In a patient with pseudoexfoliation in whom we are very worried about the zonular stability, having a very reproducible capsulorrhexis and putting less stress on the zonules may be of significant benefit and may reduce the chance of vitreous loss or other complications.

Dr. Rhee: I agree. It might have potential, but as you point out very appropriately, with all of our new devices and procedures, whether it's femtosecond laser, the iStent, or the Trabectome, we have to weigh the costs and the benefits and balance those with the risks.

Thank you very much for sharing your insights, Dr. Patel. This is Dr. Douglas Rhee with Dr. Shuchi Patel for Medscape Ophthalmology Insights.