Ocular sealant helps ensure wound integrity in pediatric cases

Take-home message: In pediatric cataract surgery, use of an ocular sealant not only also helps prevent wound leakage but also provides extra protection against eye rubbing and wound manipulation.

By M. Edward Wilson, MD, Special to Ophthalmology Times

In many cases the traditional clear corneal incisions in adult cataract surgeries are self-sealing and typically have minimal effect on astigmatism while requiring less healing time. If the wound does not seal sufficiently, sutures are generally used.

Sutures, however, do not always seal as well as generally thought.^1-4 This is true when discussing pediatric cataract surgery.

Pediatric eyes present a unique challenge, as the tissue is very different from adult eyes. Children’s eyes are naturally much smaller and have low scleral rigidity and thicker and softer corneas. Children are also much more likely to rub their eyes and are less compliant with activity restriction, putting them at increased risk of trauma and postoperative infection.

Complications in pediatric cataract surgery

While postoperative infection and inflammation is concerning in any patient, this is compounded when dealing with pediatric patients. Children are especially prone to an additional variety of postoperative complications including axial growth after cataract extraction, secondary glaucoma, posterior-capsule opacification (PCO), and future vision loss due to amblyopia.^5-7

All these factors increase the necessity for a truly closed and sealed wound, something a suture alone cannot always guarantee.

With the increased scleral elasticity and soft corneas of pediatric tissue, even small wounds tend to leak. One study was able to demonstrate secure self-sealing wounds subsequent to pediatric extracapsular cataract extraction (ECCE) with posterior capsule preservation and IOL insertion.⁸

However, this does not seem to be the typical response as other surgeons attempting similar techniques still found it necessary to use a suture against leakage.^9,10

A prospective study examining pediatric sutureless wounds illustrated a high leakage rate with 100% leakage in eyes of patients below 11 years of age who underwent ECCE, primary posterior capsulotomy, anterior vitrectomy with intraocular lens implantation (ECCE + PPC + AV + IOL).

Consequently, suturing every pediatric wound is recommended. Most pediatric cataract surgeons utilize synthetic absorbable 10-0 polyglactin (Vicryl) suture but it does not have the same handling characteristics of conventional 10.0 nylon monofilament suture generally employed in adult surgery.¹¹

Vicryl is more difficult to titrate and can easily be tied too tight, producing a lot of temporary astigmatism, or too loose, allowing a persistent wound leak.¹²

Adding an ocular sealant

Pediatric wounds often leak when the child rubs the eyes, even when sutured. To combat this, the use of a hydrogel ocular sealant can further prevent wound leakage, thus ensuring greater positive outcomes.

In my practice, I use a certain sealant (ReSure Sealant, Ocular Therapeutix). This hydrogel sealant is comprised of polyethylene glycol (PEG), trilysine, buffering salts, and more than 89% water. It is tinted with FD&C Blue#1 to aid in visualization and placement. The tint dissipates quickly leaving behind a clear sealant, imperceptible to the naked eye but still visible under a scope. The sealant is packaged with a small tray with two wells and an applicator with which to reconstitute the gel. It is ready for use within seconds and can be used alone or in more complex procedures in children, as an adjunct to sutures.

While the sealant provides significant advantages in terms of wound sealing in adults, challenges still arise in pediatric cases. With adult tissue, it is possible to completely dry the ocular surface, which allows the sealant to adhere. This is not the case with pediatric eyes. In the pediatric tissue, it is not usually possible to get the wound dry enough initially to apply the sealant. A suture must still be used to close the wound.

However, the sealant can then be applied by simply brushing it over the sutured wound, making it useful as a secondary safety net, forming an air-tight barrier against infection and eliminating the need to sew the pediatric wounds quit so tight. It also provides extra protection against eye rubbing and wound manipulation, making the wound more stable.  For very small leaks, the sealant may work as a substitute for a suture. In most cases in young children though, a suture will still be needed with the sealant over the suture.

I utilize this strategy in most of my recent cases and have used it to date in more than 50 pediatric procedures. While the surgery itself can be complicated and challenging it is essential that the integrity of the wound be not overlooked. Knowing the incision is truly sealed and that these young patients are as protected against post surgical-complications as possible offers great peace of mind.

References

1. Chee SP. Clear corneal incision leakage after phacoemulsification–detection using povidone iodine 5%. Case Report. Int. Ophthalmology. 2005;26:175-179.

2. Mifflin MD, Kinard, K, et al. Comparison of Stromal Hydration Techniques for Clear Corneal Cataract Incisions: Conventional Hydration versus Anterior Stromal Pocket Hydration. Journal of Refractive Surgery. 2012;38:933-937.

3. Herretes S, Stark WJ, et al. Inflow of ocular surface fluid into the anterior chamber after phacoemulsification through sutureless corneal cataract wounds. American Journal of Ophthalmology. 2005;140;737-740.

4. Masket S, Hovanesian J, et al. Use of a calibrated force gauge in clear corneal cataract surgery to quantify point-pressure manipulation. J Cataract Refract Surg. 2013 Feb 21.

5. Vasavada AR, Raj SM, Nihalani B. Rate of axial growth after congenital cataract surgery. Am J Ophthalmol. 2004;138:915–924. 

 6. Mataftsi A, Haidich AB, Kokkali S, et al. Postoperative glaucoma following infantile cataract surgery: an individual patient data meta-analysis. JAMA Ophthalmol. 2014;132:1059–1067.

7. Lim Z, Rubab S, Chan YH, Levin AV. Management and outcomes of cataract in children: the Toronto experience. J AAPOS. 2012;6:249–254.

8. Vasavada AR, Chauhan H. Intraocular lens implantation in infants with congenital cataracts. J Cataract Refract Surg 1994;20:592-598.

9. Gimbel HV, Ferensowicz M, Raanan M, Deluca M. Implantation in children. J Pediatr Ophthalmol Strabismus. 1993;30:69-79.

10. Zetterstrom C, Kugelberg U, Oscarson C. Cataract surgery in children with capsulorhexis of anterior and posterior capsules and heparin-surface-modified intraocular lenses. J Cataract Refract Surg. 1994;20:599-601.

11. Lavrich JB, Goldberg DS, Nelson LB. Suture use in pediatric cataract surgery: A survey. Ophthalmic Surg. 1993;24:554-555.

12. Bar-Sela SM, Spierer O, Spierer A. Suture-related complications after congenital cataract surgery: Vicryl versus Mersilene sutures. J Cataract Refract Surg. 2007;33:301–304.

M. Edward Wilson, MD

E: wilsonme@musc.edu

Dr. Wilson is the N. Edgar Miles Professor of Ophthalmology and Pediatrics at the Storm Eye Institute, Medical University of South Carolina, Charleston, SC. He also serves on the AAPOS Board of Directors, as the President-Elect of AAPOS, and is the incoming Chair of the governing Council of the American Ophthalmological Society. Dr. Wilson reports no financial interests relevant to this topic.