Purpose: The aim of this study is to investigate the utility of fractal analysis in establishing the diagnosis of LVNC in paediatric population.
Methods: Altogether 84 subjects were analysed: 1) 28 patients with LVNC as defined by Petersen on CMR (ie non-compacted to compacted layer (NC/C) ratio>2.3); 2) 28 patients referred by clinicians for CMR with hypertrabeculation and found not to qualify as LVNC by Petersen (ie NC/C < 2.3); 3) 28 subjects (controls) with a normal scan. All 3 groups were age and gender matched.
The fractal scores for each group were presented for 3 sites in the left ventricle (LV): basal, mid and apical layer, as well as global LV score (mean) and maximal score. Statistical comparison of the fractal scores between the 3 groups has been performed.
Results: Global fractal dimension (FD) was higher in the LVNC group than in the hypertrabeculated group (1.35±0.05 vs 1.25±0.03, p<0.001) and higher in hypertrabeculated group than in controls (1.25±0.03 vs 1.16±0.04, p<0.01). Maximal FD was the highest in the LVNC group and higher in hypertrabeculated group when compared to controls (1.48±0.04 vs 1.35±0.03, p<0.01; 1.35±0.03 vs 1.26 ± 0.04, p<0.01). The highest mean FD was in the apical part in LVNC group (1.43±0.06) whereas it was 1.30±0.03 in the mid ventricle in hypertrabeculated and 1.23±0.04 in the healthy group.
Conclusion: There are multiple diagnostic difficulties in establishing LVNC diagnosis in children. We have shown that it is technically feasible to perform fractal analysis in children using CMR. Fractal scoring accurately distinguishes between LVNC, LV hypertrabeculation and healthy controls. This may help with the diagnostic limitations of the currently used diagnostic CMR methods.