Chat Highlights – February 20, 2013
Guest Speaker – Dr. Michael Pro
Lorraine Miller, Editor, Chat Topic Researcher
Moderator: This evening’s topic is “Glaucoma Research” and we would like to welcome our glaucoma expert, Dr. Michael Pro. Welcome, Dr. Pro!
Dr. Pro: Good evening, everyone!
P: Dr. Pro, what glaucoma research interests you the most?
Dr. Pro: Great question. Personally, I like research involving glaucoma surgery. I like to look into new glaucoma surgery techniques or devices. I am so fortunate to be at Wills where so many venues of research are being investigated.
P: Are you working on a research project?
Dr. Pro: I am working on several. One project that I am currently involved with is looking into the use of Ologen in place of mitomycin C in trabeculectomy surgery. This is a multicenter study (in other words, it involves many different sites and surgeons).
P: What is Ologen? What is the suspected benefit?
Dr. Pro: Ologen is a collagen matrix that is used to improve or modify wound healing. For trabeculectomy surgery, a small patch of ologen measuring about 6 mm is placed over the scleral flap at the end of the case and the conjunctiva is closed over everything. The ologen helps to prevent scarring at the level of the scleral flap. Some patients may benefit from avoiding the use of mitomycin C (MMC). MMC helps to prevent scarring at the level of the scleral flap. MMC may also cause some early and late term complications such as hypotony (low IOP) and bleb leaks.
P: With so many new advances happening, is there anything new to restore even partial vision for someone who has lost almost all vision from glaucoma?
Dr. Pro: We are working on that. But for now, I am afraid to say, we do not have much to offer.
P: Is there any new information you could share with us pertaining to stem cell research results and glaucoma?
Dr. Pro: This is a commonly asked question. Many intelligent patients with glaucoma understand that if stem cells could be used to regenerate dead and dying retinal ganglion cells (RGCs) then their vision could be restored. Unfortunately, this is a very difficult problem. It has proven easier to regenerate the RGCs in a laboratory environment than to translate it into clinical practice. The problem is that the visual pathway is so very complex. Even if we could get new RGCs to grow from stem cells, it is not understood how we would cause them to make the proper connections in the visual pathway in the brain. So for now, stem cell research may have slightly more immediate prospects in retinal disease such as macular degeneration. Attention is now turned towards neuroprotection drugs or the prevention of glaucoma damage in the first place.
P: What area of glaucoma research is the most time and money spent?
Dr. Pro: I don’t know exact numbers, but I would think that the most money is spent on the development of new glaucoma drugs or drops. In the last decade, there seems to be more energy and money spent on new glaucoma surgery devices.
P: Are there any new glaucoma medications that are being researched that look promising?
Dr. Pro: For the past several years, there have been several companies looking into RhoKinase inhibitors. Several years ago, Wills was a study site for a drug of this class, but at this time, none of these drugs have come to market.
P: I had a long-time partner who developed terminal cancer. My pressures had been in the 13-14 range until my last appointment when they were 19 each. Could stress raise my pressures?
Dr. Pro: Another great question and one that I am asked just about every day. The quick and honest answer is that we don’t really know. It is not ethical to induce stress in some study subjects and compare them to relaxed individuals. I think it is logical to presume that emotional states can affect multiple organ systems and may also affect IOP (intraocular pressure).
P: Could stress and IOP be studied by doing a baseline stress analysis at various stress scale measurements of a patient and then track that same patient over time to see if changes on their stress score correlate to IOP changes?
Dr. Pro: Maybe, but there are confounding variables that would need to be controlled. For instance, maybe stressed individuals eat less healthy food and it is really the diet that affects the IOP. But, it is a nice thought. Maybe we should try to look into that!
P: It would be nice to know if diet affects IOP!
P: Are new lasers under consideration?
Dr. Pro: Yes, there is an Israeli company that is investigating a CO2 laser to help with a type of glaucoma surgery called a deep sclerectomy or a safer version of a trabeculectomy. There is also a laser system called the Excimer laser, which has been explored and is like an SLT (Selective Laser Trabeculoplasty) in its application. It causes small holes to be formed which allow the aqueous fluid to reach the canal of Schlemm and the collector system.
P: Alternative treatments are always of interest to patients. Do you know of any new research in the area of supplements to help in the treatment of glaucoma?
Dr. Pro: For many years, the glaucoma community has wondered about ginkgo biloba as a supplement which may possibly improve optic nerve perfusion. Studies on supplements that help people with glaucoma are really lacking. This is in contrast to macular degeneration, where certain nutrients have proven beneficial in certain patients with macular degeneration.
P: Are there any promising results from the current research being performed at Wills?
Dr. Pro: Dr. Spaeth has spearheaded a long line of research into the functional impact that glaucoma has on patients’ lives. Understanding this may improve the designs of everyday objects as well as public and private spaces. Wills is currently involved in a massive glaucoma screening effort which may allow doctors and policy makers to better understand how to identify persons at risk for glaucoma and treat them earlier. There are numerous other studies that may change the way we care for our glaucoma patients.
P: Are there new developments in the area of primary open-angle glaucoma (POAG)?
Dr. Pro: The biggest change here has been the development of new glaucoma surgery devices. The iStent is now available in the U.S. It is a 1mm metal device that inserts into the drainage area of the eye during cataract surgery. It allows better outflow of aqueous fluid from the eye into the Schlemm’s canal and collector system. There are other devices similar to this in development, too.
P: Is research providing good results for the treatment of angle-closure glaucoma?
Dr. Pro: Not as much as in POAG. I think analysis of patient data and various small studies point out that cataract surgery can benefit individuals with angle-closure and may help to improve IOP control.
P: Is research in the area of normal tension glaucoma finding any evidence as to the cause of vision loss while pressures are within normal limits?
Dr. Pro: There is evidence that low nocturnal blood pressure may be part of the issue in this small subset of glaucoma patients.
P: Any new findings with the less prevalent glaucomas: pigmentary, pseudoexfoliative, neovascular or Irido Corneal Endothelial (ICE) syndrome?
Dr. Pro: Not as much. Previously, we thought that ICE syndrome may be due to a herpetic infection. Now some researchers are less certain.
Moderator: Thank you, Dr. Pro. This concludes our moderated chat for tonight.
Dr. Pro: Good night, everyone.