Damian McNamara

April 09, 2013

BOSTON, Massachusetts — Ophthalmologists can take steps to spare children the short- and long-term complications of pediatric cataract surgery.

Retinal detachment and endophthalmitis are 2 major adverse events so serious that prevention is of paramount importance, said M. Edward Wilson, MD, professor of ophthalmology and pediatrics at the Storm Eye Institute, Medical University of South Carolina, in Charleston.

"This is a call to action," Dr. Wilson said when delivering the Frank D. Constenbader lecture here at American Association for Pediatric Ophthalmology and Strabismus 39th Annual Meeting. "What we do in surgery matters, and it may matter for years to come, even if you choose to leave the posterior capsule intact."

Dr. Wilson presented case series of 658 eyes, and reported that retinal detachment and endophthalmitis affect less than one half of 1% of eyes undergoing cataract surgery. Despite the relative rarity of these adverse outcomes, he offered a best-practice approach to vitrectomy to minimize their occurrence.

For example, the risk for retinal detachment can be minimized with perioperative efforts to decrease inflammation and traction. In addition, intracameral antibiotic injections can significantly decrease the chance of postoperative endophthalmitis.

Dr. Wilson and his team analyzed 658 eyes that underwent planned posterior capsulectomy and vitrectomy. Eyes with an intact posterior capsule or a posterior capsulorhexis with an intact vitreous were excluded from this analysis. Some children were left aphakic in infancy and implanted at a later age.

Table. Surgical Approaches to Vitrectomy

Technique Eyes (n = 658)
Pars plana 371
Limbal 287
Primary intraoperative lens 491
Initial aphakic 167
Bilateral 404
Unilateral 254

 

Retinal detachment occurred in 3 of 658 eyes (0.45%) over a mean follow-up of 5.9 years (range, 6 months to 20 years). One incident occurred 5 months after cataract surgery with no intraoperative lens placement in an eye with persistent fetal vasculature syndrome. The second occurred 19 months after cataract surgery with no intraoperative lens but also after Seton glaucoma surgery. The third happened 7 years after surgery with intraoperative lens, but again after Seton glaucoma surgery "and at the time of a motor vehicle accident severe enough to rupture a spleen," Dr. Wilson reported.

The relation between pediatric cataract surgery and retinal detachment is indirect. The underlying mechanism involves inflammation and traction forces that alter vitreous biochemistry. These alterations can accelerate the change of vitreous gel to liquid, making the vitreous more mobile. "If there is a place of adhesion or constant vitreous in the wound, that's where it's going to tear as it becomes more mobile," he explained.

"We also know that excessive flow rates and low cutting rates cause a tremendous amount of intraoperative traction," said Dr. Wilson. He recommends newer, more advanced vitrectomy devices that can make up to 7500 cuts per minute. "These smaller and more efficient high-speed cutters are safer, with less vitreous traction during surgery."

Intraoperative triamcinolone injection is a strategy that is supported by multiple studies, Dr. Wilson noted. For example, in a randomized controlled study of 120 adult eyes, intracameral triamcinolone 1 mg was associated with a 7-fold reduction in vitreous strands and vitreous traction (Eye. 2010;24:619-623).

 
We need to manage these lifelong retinal risks
 

In the series analyzed by Dr. Wilson's team, 4 eyes (0.61%) were infected with endophthalmitis. One infection occurred in a 5-month-old child who underwent cataract surgery with intraoperative lens. "The others were more complex," Dr. Wilson said. Two occurred after repeated glaucoma surgery — an aniridic patient 10 months of age and a patient with Sturge–Weber syndrome 3 years and 8 months of age. The other case occurred after the removal of a dislocated intraocular lens caused by self-trauma in a Down's syndrome patient.

Dr. Wilson reported that since he began using intracameral nonpreserved moxifloxacin at the completion of surgery 2 years ago, he has had no cases of endophthalmitis.

"Use intracameral antibiotics," he advised. "Choose your antibiotics and use them. They are proven. This is the era of intracameral drugs and safer, less traumatic intraocular surgery."

In a study of 464,996 cataract surgeries in adults, only the nonuse of intracameral antibiotics and communication with the vitreous significantly increased the risk for endophthalmitis (J Cataract Refract Surg. 2013;39:15-21).

"Several studies have also looked at topical antibiotics," Dr. Wilson said. "Topical antibiotics applied postoperatively do not add additional protection from endophthalmitis."

"The management of the vitreous during surgery for congenital cataract has changed beyond recognition [in the past 10 or 15 years]. Although it will still be many years before we know the long-term impact on retinal morbidity, it is likely that the newer techniques and equipment will be highly beneficial," said David Taylor, MD, professor emeritus of pediatric ophthalmology at University College London, United Kingdom, who was asked by Medscape Medical News to comment.

A meeting attendee asked about intracameral triamcinolone inadvertently placed in the vitreous cavity. "I routinely place it in the anterior chamber and it dissipates quickly. If I place any in the vitreous cavity, I remove it," Dr. Wilson explained, adding that his aim "is not to leave any triamcinolone in the vitreous."

"Vitrectomy is not going to go away. In young patients [with congenital cataracts], vitrectomy and capsulectomy are essential," Dr. Wilson said. Therefore, any reasonable effort to reduce the risk for serious adverse outcomes is worthwhile.

The responsibility of ophthalmologists extends beyond the perioperative period. "We need to manage these lifelong retinal risks," Dr. Wilson said. "We are obligated to follow these patients for many years. We know retinal detachment can occur weeks, months, or decades later."

The Costenbader Lecture is supported by the Children's Eye Foundation. Dr. Wilson reports receiving royalties from Springer Publishing. Dr. Taylor has disclosed no relevant financial relationships.

American Association for Pediatric Ophthalmology and Strabismus (AAPOS) 39th Annual Meeting. Presented April 4, 2013.

processing....