Abstract
Abstract: :
Purpose:Spina bifida (SB) is a neural tube defect sometimes associated with hydrocephalus, which often requires intraventricular shunt placement. Reported ophthalmic associations include strabismus, disc edema, and optic atrophy. This study involves correlating (a) number of shunts or (b) location of SB defect with abnormal ocular findings. Methods:This is a retrospective chart review of 136 patients (75% under 18 years) with SB at OHSU. Demographic information, location of spinal cord lesions, number of shunt procedures, and shunt complications were obtained. There were 82 patients with available ophthalmic findings, including visual acuity, ocular motility, status of ocular structures, and the presence of ocular disease. Data were explored by descriptive statistics and then likelihood ratio tests. Results:Among the 82 patients with eye findings, age ranged from one month to 47 years (75% under 18 years). Eighty–nine percent of patients had shunts placed for hydrocephalus. The number of shunt operations ranged from 0 to 14. Amblyopia was more likely to occur in patients with multiple shunt operations: 1 of 5 patients (20%) without shunts, 3 of 25 patients (12%) with 1–2 shunts, and 12 of 26 patients (46%) with greater than 3 shunts. The level of the SB defect correlated with strabismus (p=0.009), optic nerve abnormalities (p=0 .005), and nystagmus (p=0.005). Strabismus was most likely to occur in patients with higher spinal cord lesions: 9 of 11 patients (82%) with thoracic lesions, in 6 of 22 patients (27%) with upper lumbar lesions, and 14 of 27 patients with lower lumbar lesions (52%). More optic nerve abnormalities occurred in higher spinal cord lesions: 5 of 10 patients (50%) with thoracic lesions, 8 of 19 (42%) with upper lumbar (L) lesions, and 2 of 26 (8%) with lesions below L3. There was an increased prevalence of nystagmus in patients with higher spinal cord lesions: 6 of 9 patients (67%) with thoracic lesions, as opposed to 6 of 44 patients (14%) with lesions in the lumbar or sacral regions. There are no statistically significant correlations between the (a) number of shunts/revisions or (b) level of lesion with decreased visual acuity, afferent pupillary defect, media opacity, or retinal abnormality. Conclusions:There is a high incidence of ophthalmic findings in patients with spina bifida at OHSU. There is a greater risk of amblyopia in patients with 3 or more shunts or revisions. Patients with higher spinal cord lesions have more strabismus, optic nerve abnormalities, and nystagmus.
Keywords: amblyopia • strabismus • nystagmus