Cataract and AMD
Cataract and AMD
In “The Cataract-AMD Connection: Fact or Fiction?” (Clinical Update, June), George A. Williams, MD, voices criticism of the 1996 Ophthalmology report by A. Pollack et al., which demonstrated AMD progression more often in eyes that underwent planned extracapsular surgery than in control eyes. “One could question whether it’s applicable in the phacoemulsification era,” he said.
Some will argue, surely, that such criticism is not due. For all of the eyes in the Pollack study, the posterior capsule remained intact. The important point to realize is that 19 percent of eyes (nine of 47) with multiple hard and soft macular drusen developed a choroidal neovascular membrane within the first 12 months following cataract surgery, while only 4 percent (two of 47) of the fellow eyes succumbed to that same complication. The study was restricted to individuals with symmetrical macular AMD findings.
For the time being we have no better scientific information to guide us. Curiously, Dr. Williams does not explain why he does not advocate additional prospective studies of the Pollock type so that meaningful data regarding the cataract-AMD connection, whether it be fact or fiction, would become available to patient and ophthalmologist alike.
In the same EyeNet article, Steven T. Charles, MD, notes that when visual loss is attributed to the cataract surgery, the causation could be the result of preexisting and undetected AMD.
But such remarks sidestep the point of everyone’s concern, which is: Does cataract surgery hasten, somehow, the AMD process? His comments support the widely held belief that the status of the macula needs to be carefully assessed before cataract surgery is done, but they do not offer advice regarding what should be done when AMD is detected in an eye that has also developed a cataract.
W. Rex Hawkins, MD
Cataract Controversy: Endophthalmitis” (June) addresses the question “What about prophylaxis?” This is still of immense and current interest for cataract surgeons.
I would like to briefly report on my experience with approximately 8,000 patients with scleral tunnel preparation, phacoemulsification and N-butyl-2-cyanoacrylate (Histoacryl) glue closure between 1995 and 2003. I have developed a six-step glue technique that I perform in the same manner that I administer antibiotic drops pre- and postoperatively.
Histoacryl glue causes a waterproof closure of the groove of the scleral tunnel. To this day, we have not observed any signs of endophthalmitis, which indicates the anti-inflammatory and bacteriostatic properties of Histoacryl.
Dhalla et al. reported in the June 2001 EyeNet (“Tips on Using Cyanoacrylate Glue,” Ophthalmic Pearls) about the use of cyanoacrylates in the treatment of corneal perforations, corneal thinning, leaking filtering blebs and others. Simultaneously they described the anti-inflammatory effects and the bacteriostatic properties of Histoacryl.
At the end of Dhalla’s 2001 article there was a reminder that despite extensive use by U.S. ophthalmologists, cyanoacrylates are not approved by the FDA for use on the eye. The glue is available from manufacturers in Germany and Canada.
Walter Lisch, MD
Correction: 2004 Final Program
The Academy has received corrections to data in a Free Paper presented at the 2004 Joint Meeting by James P. McCulley, MD, FACS, titled Comparative Penetration of 2 Fourth-Generation Fluoroquinolones Into the Aqueous Humor of Humans. (See page 77 of 2004 Final Program.) The corrections are as follows: 1) There were 40 rather than 30 patient samples assayed. 2) Moxifloxacin concentration in aqueous humor was 1.88 +/– 0.52 micrograms/milliliter. 3) Gatifloxacin concentration in aqueous humor was 1.06 +/– 0.36 µg/ml. 4) P < 0.007.
Write to Us
You can write to us at:
Editors, EyeNet Magazine
American Academy of Ophthalmology
665 Beach Street
San Francisco, CA 94109
EyeNet reserves the right to edit letters.