Innovation Alive and Well in Retina
JASON S. SLAKTER, MD
Having just returned from the third annual Retinal Physician Symposium
held at Sanibel Island Resort in Florida, I am pleased to report that the
field of retina is alive and well in 2007.What was obvious throughout the
meeting was retinal specialists’ genuine interest in emerging technologies and new
approaches to treating disease, as well as a true desire to understand the underlying
nature of the conditions that we treat and find better ways to manage them.
Perhaps no single diagnostic test has had more impact in the management of
retinal disease in recent years than optical coherence tomography (OCT). In just a
short time, OCT has come to supplant fluorescein angiography (FA) as the mainstay
of monitoring for treatment response in age-related macular degeneration
(AMD), as well as in diabetic macular edema. Part of this conversion is due to the
fact that the OCT system currently in widespread use, the Zeiss Stratus OCT-3
system, provides both visual and numerical outputs that are straightforward and
easy to interpret.Traditional FA has always proved to be a challenge in many situations,
with difficulties in distinguishing between classic and occult choroidal neovascularization,
identifying areas of staining vs leakage, and even determining
whether a lesion was subfoveal or extrafoveal.While many of these factors were
important in the management of AMD in the past, the advent of pharmacologic
therapy focused our attention on the degree of vascular activity or leakage. OCT
obviates these difficulties by presenting an output that is easily readable.
On the other hand, we have also come to realize that the OCT systems
currently in widespread use have their faults. These include the difficulty with
image registration, as well as software interpretation errors that result in inconsistent
or inaccurate numerical values for retinal thickness. In addition, FA is
still required for diagnosis and documentation of the neovascular lesions.
NEW OCTS ARE ARRIVING
As Alexander Walsh,MD, writes in this issue of Retinal Physician, OCT
imaging is undergoing a radical change. The new spectral domain (SD)-OCT
systems will dramatically change the way we image the posterior pole. Dr.
Walsh thoroughly and completely compares and contrasts the systems that will
be on the market over the next year. I am convinced that this information will
prove extremely valuable in selecting the right system for your needs.
A note of caution, however, should be mentioned. Until now,OCT was nearly
synonymous with the Zeiss Stratus unit. As pointed out by Dr.Walsh, at least 6
new systems will be available, with different methods of data presentation. As
SD-OCT evolves, retinal specialists must be cognizant of these differences and
exercise care in the interpretation of the data SD-OCT presents until standardized
or comparative algorithms are developed. Despite this drawback, competition is a
good thing and will likely result in improved quality and reduced price — benefits
to both us as physicians and to our patients.
Retinal Physician, Issue: May 2007