Taking into consideration the increased risk for development of glaucoma after early extraction of congenital cataracts, do you recommend performing this surgery before 4 weeks of life or after?

Surgery between 4 and 8 weeks reduces risk

David G. Morrison

In the past, most discussions of congenital cataract have centered around the question, “How late can surgery be performed to avoid deprivation amblyopia?” The publication of Vishwanath’s article in 2004 has now changed this question to, “When is too early for surgery to reduce the incidence of glaucoma?” Glaucoma is common after surgery for infantile cataract. Vishwanath and colleagues demonstrated that this rate was higher in children who had surgery before 4 weeks of age. Subsequent authors, mostly from the United Kingdom, have confirmed this finding.

One does need to examine these data critically because congenital cataract is often associated with other abnormalities such as microphthalmia, persistent fetal vasculature, and anterior segment or angle anomalies that may influence the development of glaucoma. However, my anecdotal experience is similar. The newborn infant’s eye is different when compared even with an eye at 4 weeks. Scleral rigidity is low, resulting in a great deal more intraoperative posterior pressure and frequent shallowing of the anterior chamber during surgery. The iris can be immature and floppy. These, or other unrecognized structural effects of early surgery, may change the angle or trabecular meshwork and eventually precipitate glaucoma. While previous authors have questioned whether the placement of an IOL may prevent glaucoma, most now believe that this was simply a selection bias based upon the fact that only older children with healthier eyes received IOLs.

In conclusion, the guiding principle of medicine is “First, do no harm.” The work of Birch and others has demonstrated that a critical period for lens removal to facilitate visual development exists around 6 weeks in unilateral cataract and even later with bilateral lens opacity. Therefore, I now recommend that a child have surgery between 4 and 8 weeks to reduce the risk of glaucoma yet still facilitate maximal visual development.

David G. Morrison, MD, is assistant professor of ophthalmology and pediatrics at Vanderbilt University and was an investigator in the NEI-sponsored Infant Aphakia Treatment Study. Disclosure: Dr. Morrison has no relevant interests to disclose for this article.

Reference:

• Vishwanath M, Cheong-Leen R, Taylor D, Russell-Eggitt I, Rahi J. Is early surgery for congenital cataract a risk factor for glaucoma? Br J Ophthalmol. 2004;88(7):905-910.

Weigh risks and benefits

Deborah K. Vanderveen

Several studies have suggested that “early” surgery is a risk factor for complications after congenital cataract surgery, including development of aphakic glaucoma, which must be weighed against the benefit of better visual outcome with early surgery. The definition of early surgery is varied, with 4 weeks being one cut point used, though later ages such as 6, 8, or 10 weeks have also been suggested. Presence of microcornea has also been suggested as a risk factor for later development of glaucoma, as have PFV [persistent fetal vasculature] or other anterior segment abnormalities. While most pediatric cataract surgeons agree that visual outcomes are better with surgery before 2 months of age, Birch and colleagues have also suggested that final visual acuity may decrease by 1 line with each 3 weeks’ delay in surgery.

In the end, based on all these factors, I do avoid surgery in the first 3 weeks of life if possible, since there is likely little visual advantage, and perhaps some increased risk to the child of ocular or anesthetic complications with very early surgery. I would not view 4 weeks as a “hard stop” for glaucoma risk, however, and many other factors come into play including overall infant health status, or simple OR scheduling availability. Usually I try to schedule these infants for surgery when they are 3 to 6 weeks of age, working around all these factors, and still of course let parents know that there is a risk of developing glaucoma later, which must be monitored over the years.

Deborah K. Vanderveen, MD, is assistant professor of ophthalmology at Massachusetts Eye and Ear Infirmary, Childrens Hospital, Boston. Disclosure: Dr. Vanderveen has no relevant interests to disclose for this article.

Waiting 4 weeks is reasonable

Uday Devgan

Ocular development occurs most profoundly in utero but continues after birth, particularly in the first few weeks of infancy. For babies born with congenital cataracts, it is important to perform early lensectomy to prevent visual deprivation and amblyopia, but this must be balanced with the risk of potentially disturbing angle development, which could lead to glaucoma. It appears that a reasonable timeline is waiting 4 weeks after birth before proceeding with lensectomy surgery.

In addition, there may be additional advantages to performing minimally invasive 25-gauge surgery, such as faster recovery, less induced astigmatism and perhaps less of a risk of glaucoma from iatrogenic causes. At our facility, Olive View UCLA Medical Center, we wait until after the first month of life and use this microincisional technique that we feel results in better outcomes. It should be emphasized that while the surgical treatment of the congenital cataract is important, the years-long treatment of amblyopia is even more so.

Uday Devgan, MD, FACS, FRCS(Glasg), is OSN SuperSite Section Editor and chief of ophthalmology, Olive View UCLA Medical Center, Los Angeles, and Federico Velez, MD, is head of the Pediatric Ophthalmology & Strabismus Department, Olive View UCLA Medical Center. Disclosure: Dr. Devgan and Dr. Velez have no relevant interests to disclose for this article.