DEC 13, 2011
This prospective study examined whether children with cerebral palsy (CP) at varying motor function levels differ in their outcomes or need for reoperation after attempted strabismus repair. Based on their treatment of 50 children, the study’s authors report in the September issue of Investigative Ophthalmology & Visual Science that restoration of binocular alignment and a degree of fusion is a realistic goal in the majority of strabismic children with CP. They conclude that repair may be achieved in children at all levels of the Gross Motor Function Classification System (GMFCS) spectrum without undue concern about treatment futility or excessive reoperation.
They conducted this study since children with CP tend to be either excluded from studies of strabismus repair or pooled with children with other neurologic disorders. Children in this study ranged from GMFCS level 1, the least severe, to level 5, the most severe. They were a mean age of 3.5 years when entering the study and undergoing surgery, and were followed for a mean of 4.1 years.
The predominant form of strabismus among the subjects was infantile-onset, with esotropia in 54 percent, exotropia in 26 percent and dyskinesia in 10 percent. Sixty-six percent of esotropic children achieved optimal (microtropic) alignment after an average of two surgical procedures, as did 61 percent of exotropic children after 1.8 procedures. The likelihood of optimal alignment was similar in children with mild CP (GMFCS levels one or two) versus severe CP (GMFCS level three through five; P = 0.7).
Forty-six percent of children in the study gained binocular fusion/stereopsis. However, those with mild CP had a two to three times greater chance of gaining Worth/Polaroid four-dot fusion or stereopsis, and children with more severe CP had less chance of gaining fusion even when their eyes were optimally realigned. The quality of fusion gained was greater in children with mild CP (P < 0.05).
All of the subjects with dyskinetic strabismus had severe CP. None of them responded favorably to surgery, which confirms the results of previous studies. There was a significantly higher rate of restoring alignment, fusion and stereopsis in children with shorter durations of strabismus before the first surgery.