Age-related changes of susceptibility-weighted imaging in subependymal nodules of neonates and children with tuberous sclerosis complex

Objectives: To assess age-related changes in susceptibility-weighted imaging (SWI) and phase images of subependymal nodules (SENs) in neonates and children with tuberous sclerosis complex (TSC).

Methods: Images of 17 children (age range, 0-14years; mean, 5.5years) with TSC were retrospectively assessed. Changes in signals of SENs on SWI and filtered phase images were scored by two experienced radiologists using a three-point scale. The relation was assessed between patients' age and the average scores of SENs. The phase shift of SENs on the filtered phase image was also measured, and the correlation between age and phase shift was evaluated. Calcification in SENs on CT was compared to the finding on SWI and filtered phase image in four children.

Results: No change in signal was found in neonates in SENs on both SWI and filtered phase image. There was a positive correlation between the average scores of SENs and patients' age on both SWI and filtered phase image (Spearman ρ=0.64, P=0.006; ρ=0.71, P=0.001, respectively). There was a negative correlation between the patients' age and mean phase shift (Spearman ρ=-0.86, P<0.001). Comparable or slight lower detectability of susceptibility changes was revealed in SENs on SWI and filtered phase image, compared to calcification on CT.

Conclusions: There are age-related changes in susceptibility and phase in SENs, which may reflect the appearance of calcification in children with TSC. No magnetically susceptible changes were detected in neonates, suggesting a lack of calcification.