Visual evoked potentials after hematopoietic allogeneic stem cell transplantation in childhood

To study visual pathway pathology detected by visual evoked potentials (VEPs) in patients treated with hematopoietic stem cell transplantation (HSCT) in childhood and to determine the impact of adverse ocular findings, somatic diseases, and conditioning regimens on the VEP results.

Ophthalmological assessments including pattern VEPs were performed in 47 of 79 patients at a median age of 15 years (range 3-21 years) in median 6 years (1-17 years) after HSCT. Somatic data were extracted from medical records.

Eight patients of 47 (17%) demonstrated pathological VEPs with prolonged latencies bilaterally (n = 3) or unilaterally (n = 5) at their latest VEP test at an age of 12-18 years. A subnormal visual acuity was present in 8/11 eyes with pathological VEPs: one eye had cataract, six eyes had cataract surgery where of two had developed secondary cataracts. One eye had residual retinopathy of prematurity. Pathological VEPs were associated with decreased visual acuity (p = 0.00019) but not linked to gender, malignant diagnosis or conditioning.

VEP recordings showed an association with decreased visual acuity but no relationship with irradiation or chemotherapy in the present study.

VEP recordings might be of clinical value for children with an unexplained subnormal visual acuity undergoing HSCT.