MAGNETIC-RESONANCE-IMAGING OF HETEROTAXIA IN INFANTS

Objectives. This study assessed the usefulness and safety of magnetic resonance imaging (MRI) for systematically diagnosing heterotaxia in i nfants. Background. Although it is important to diagnose and treat inf ants with heterotaxia, which is associated with viscerobronchial cardi ovascular anomalies, systematic diagnosis of these anomalies by a sing le imaging technique is difficult. Methods. Twenty patients with heter otaxia were evaluated. The infants ranged in age from 21 days to 12 mo nths (average 5.2 months, average body weight 4.3 kg). Electrocardiogr aphically gated MRI was performed by spin echo imaging techniques oper ating at 0.5 tesla. Results. In all 20 patients, MRI results were suff icient to evaluate these anomalies without serious complications. In 1 7 patients, neither a spleen nor splenules were detected, but in 3 pat ients, a polymorphous spleen was visualized. In all 20 patients, bronc hial anatomies were dearly visualized (bilateral eparterial bronchi in 14 patients, bilateral hyparterial bronchi in 2 and normal bronchial patterns in 4). Additionally, in a comparison of 149 observations of c ardiovascular anatomy by MRI with those by angiography, discrepancies were found in only 10 observations (6.7%). Conclusions. Magnetic reson ance imaging was found to be safe and very useful for the systematic d iagnosis of heterotaxia in infants.