Cincinnati, OH—The viscous dispersive ophthalmic viscosurgical device (OVD) DisCoVisc (Alcon Laboratories Inc.) offers surgeons the opportunity to perform safe and efficient phacoemulsification with a single OVD in routine procedures and in many complex cases as well, said Michael E. Snyder, MD.
Cincinnati, OH-The viscous dispersive ophthalmic viscosurgical device (OVD) DisCoVisc (Alcon Laboratories Inc.) offers surgeons the opportunity to perform safe and efficient phacoemulsification with a single OVD in routine procedures and in many complex cases as well, said Michael E. Snyder, MD.
"This unique product remains in the eye to maintain space and chamber stability nicely, affords excellent protection of the cornea and other intraocular tissues with good intraoperative visualization, and is still easy to remove at the end of the case," said Dr. Snyder, who specializes in cataract and anterior segment surgery at Cincinnati Eye Institute, Cincinnati, OH. "I have been consistently pleased with all aspects of its performance in routine cases and for some special situations, and so DisCoVisc has become my OVD of choice for all but the most complicated procedures."
Several observations confirm that DisCoVisc provides continued endothelial protection throughout the case. When the cortex is removed at the end of the procedure, Dr. Snyder noted it is not unusual to aspirate some DisCoVisc from the corneal dome as he turns the aspiration port upward.
That feature is corroborated by results of a premarketing clinical study evaluating change in endothelial cell density at 90 days after surgery.
"Although I have not undertaken any formal analysis of endothelial cell counts on my own, I can attest to the fact that using DisCoVisc I have continued to achieve the same clear corneas on postoperative day 1 that I have been accustomed to seeing," Dr. Snyder continued.
Increased IOP not a factor
While DisCoVisc stays where it is needed during capsulorhexis, lens removal, and IOL implantation, at the end of the case it can be easily evacuated. Perhaps related to fairly complete removal in the routine case, or perhaps because of its compositional characteristics, Dr. Snyder has found it has not been associated with postoperative IOP elevation.
"Even in eyes where I know some small amount of DisCoVisc remains in the eye, such as in cases where some OVD remains behind the IOL in primary posterior capsulorhexis or in the interstices between artificial iris element, I have not encountered any problems with increased IOP after surgery," Dr. Snyder said. "While I use prophylactic ocular antihypertensives, such as intraocular carbachol, in such cases, pressure elevations occurred much more regularly with other OVDs in the same setting."
Dr. Snyder noted he has found DisCoVisc extremely helpful in cases where there is a dense posterior capsular plaque and it is necessary to perform a primary posterior capsulorhexis. In that situation, DisCoVisc does an excellent job of maintaining and pressurizing the anterior chamber and also tamponading the hyaloid face to enable completion of the posterior capsulorhexis safely without vitreous loss, he said.
"Previously, for this technique I would use two different OVDs, a highly cohesive agent to pressurize the anterior chamber and a highly dispersive agent to push back the hyaloid face. DisCoVisc performs well for both tasks," Dr. Snyder said. There is an ample amount in one vial to achieve these and other extra manipulations without opening a second one.
He has also found DisCoVisc to have advantages in eyes where a capsular dye is being used. DisCoVisc seems to repel the capsular dye, he said. A dye introduced into an anterior chamber filled with another OVD often becomes dispersed into the OVD, impeding visibility, and it is necessary to remove and replace some of the OVD before capsulorhexis, he said. With DisCoVisc, the stain can be painted across the anterior capsule then expressed by adding more DisCoVisc, he added.
"Using DisCoVisc eliminates the additional step of aspirating the tainted OVD and saves time when using a capsular dye," Dr. Snyder said. "At the end of the case, some of the DisCoVisc may be left under the iris, but it still comes out easily and does not create any problem postoperatively."