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25-gauge tools improve congenital cataract surgery in infants
Instruments allow smaller incisions, stability of the anterior chamber, precise control and the ability for surgeons to switch hands.
The traditional techniques for pediatric cataract surgery in infants have included large incisions, many sutures, 20-gauge coaxial vitrectomy units, anterior chamber instability and significant iatrogenic astigmatism. The new 25-gauge instruments and technology have the potential to change the way that congenital cataract surgery is performed in infants. We have switched to using 25-gauge instruments for all pediatric cataract surgery at Olive View – UCLA Medical Center in Sylmar, Calif.
 Uday Devgan |
Often, the primary difficulty in pediatric cataract surgery is the instability of the anterior chamber, which is further impaired by the elastic tissues and sclera seen in infants. With the traditional 3-mm steel keratome, anterior chamber flattening is nearly instant. Adding viscoelastic helps to a degree, but because of the small size of these infant eyes, it becomes nearly impossible to maintain the anterior chamber depth. By switching to a smaller incision, just 0.5 mm wide, created with a diamond knife at the limbal margin, it is possible to use viscoelastic to maintain a deep and well-formed anterior chamber during surgery (Figure 1).
With small 0.5-mm incisions, new instruments must be used in order to perform intraocular surgery. Many manufacturers now make microforceps, microscissors and micromanipulators that allow precise control within the eye, while having shafts of 25 gauge. Because of the elastic nature of the pediatric lens capsule, performing a round capsulorrhexis can be difficult. By keeping a deep, formed anterior chamber and using the 25-gauge instruments, there is far better control for performing the anterior and even posterior capsulorrhexis (Figure 2).
For lensectomy, the 25-gauge vitrectomy instruments, now available from multiple manufacturers, allow controlled removal of the lens material, as well as provide the ability to perform a thorough anterior vitrectomy. Because of their smaller bore, the flow through the 25-gauge instruments is reduced from their 20-gauge counterparts, but it is sufficient to allow a complete lensectomy within 5 minutes. A major advantage, in addition to the small incisions, is the ability to switch hands. This allows access to the full 360· of the capsular bag during surgery and avoids the difficulty of removing subincisional lens material. In addition, the newer 25-gauge instruments have the ability to achieve cut rates of up to 1,500 cuts/minute and vacuum levels of 500 mm Hg (Figure 3).
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By placing the tiny 0.5-mm incisions about 90° apart, the incisions were astigmatically neutral. The incisions were placed superiorly, in order to have them covered by the upper eyelid during waking hours. Because of their small size and beveled nature, these incisions are remarkably self-sealing even in pediatric eyes. However, for a higher margin of safety, we placed 10-0 nylon sutures, which were then removed at the postop exam under anesthesia. Postoperatively, the patient did well, with a minimal amount of inflammation and a quick recovery. The 25-gauge instruments and technology have the potential to significantly improve the way that pediatric cataract surgery is performed (Figures 4a and 4b).
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Images: Devgan U, Velez F |
For more information:
- Uday Devgan, MD, FACS, is in private practice at the Maloney Vision Institute in Los Angeles, acting chief of ophthalmology at Olive View — UCLA Medical Center and assistant clinical professor at the Jules Stein Eye Institute. Federico Velez, MD, is head of pediatric ophthalmology at Olive View – UCLA Medical Center and an assistant clinical professor at the Jules Stein Eye Institute. They can be reached at Olive View – UCLA Eye Clinic, 14445 Olive View Drive, Suite 2C-101, Sylmar, CA 91342; 818-364-3538; e-mail: devgan@ucla.edu or velez@jsei.ucla.edu.