APAO Beijing 2010 Daily_Friday_0428 EWDaily_01-21 ASCRS NEWS_11x15-dl.qxd 9/16/10 5:57 AM Page 1
5th Anniversary Edition The News Magazine of APACRS and COS
Friday, September 17, 2010
Structure vs. function in the diagnosis of glaucoma By Chiles Aedam R. Samaniego EyeWorld Asia-Pacific Senior Staff Writer
n the first glaucoma session of the 25th APAO Congress, experts took a closer look at the relationship between structure and function in the diagnosis of the disease. Structural evaluation of the optic disc for the diagnosis of glaucoma includes quantitative and qualitative methods, said Liang Xu, M.D., professor, University of Zurich, Switzerland, of the Beijing Institute of Ophthalmology. Quantitative methods, he said, require less experience for the clinician, are easier to explain to the patient, and offer objective results. However, there is a significant overlap between normal and abnormal results. Qualitative methods, on the other hand, offer comprehensive evaluation and may detect other,
I
non-glaucomatous conditions of the eye. However, these methods require more experience to use and have not been standardized. Dr. Xu described the characteristic pattern of rim loss in glaucoma using what he called the ISNT rule. According to the rule, glaucomatous rim loss is characteristically vertical, preferring inferior (I) and superior (S) rim thinning over nasal (N) and temporal thinning (T). The pattern of rim loss is therefore a good way to differentiate glaucomatous changes from both normal and non-glaucomatous pathologic changes. Ultimately, said Dr. Xu, followup is “most important” in the evaluation of the optic disc for the diagnosis of glaucoma. It can be hard to distinguish glaucomatous from non-
continued on page 3
Beyond ophthalmology: Chinese surgeons perform
Dealing with keratectasia in teens by Matt Young EyeWorld Contributing Editor
ven after one day, the 25th APAO Congress has been many things to many different attendees. There’s one thing it hasn’t been: dull. Theo Seiler, M.D., Ph.D., proved that Thursday during his presentation titled, “Management of post corneal refractive ectasia.” He started by painting a picture of how young the LASIK population has become worldwide, which poses a unique set of challenges. “In young people below 18 years old, LASIK is starting to become considered as risky,” Dr. Seiler said. And yet it’s typical in Cairo, Egypt, for example, for a 16-year-old to opt
E
for LASIK. “You have to have in your mind that you may oversee a lot of keratectasia,” when operating on a younger patient population, Dr. Seiler said. Today, there are many ways to deal with keratectasia successfully, Dr. Seiler said. Corneal collagen crosslinking (CXL) is an option, as are using stromal rings, he said. “Contact lens wear could work,” he said. “But these patients underwent LASIK because they did not like or could not tolerate contact lens wear.” Corneal transplant procedures (such as anterior lamellar keratoplas-
ty) followed by refractive surgery also are options, he said. Dr. Seiler believes that astigmatism is less than a challenge in these patients than previously. “In penetrating keratoplasty, we would have to leave in sutures for 1.5 years,” Dr. Seiler said. “Now they’re out in a week or so after anterior lamellar keratoplasty.” One way or another, keratectasia has to be dealt with, Dr. Seiler said. “Once you make a decision that there is a progressive central steep island, it means you have to treat it,” Dr. Seiler said. “Otherwise, it will go on and show significant progression.” Dr. Seiler had many good things
to say about CXL, but he also suggested it may be the first in a series of steps to address optimal refractive outcomes after keratectasia. “Crosslinking helps not only to stabilize, but in 40% of cases the conus really is reduced,” Dr. Seiler said. In fact, research has shown that CXL stops keratoconus progression in all cases, he said. Then again, some patients need more than CXL. Dr. Seiler outlined a case in which a LASIK patient received a 3.5 D correction, although there were warning signs. The patient developed keratectasia and then under-
continued on page 3