Radiographic changes in ribs following clipping of patent ductus arteriosus in preterm infants

OBJECTIVES: There are no published reports on the rib abnormalities on the plain chest radiograph in preterm infants following surgical clipping of isolated patent ductus arteriosus. The purpose of this study was to describe changes in the ribs on the plain chest radiograph following surgical clipping of patent ductus arteriosus (surgery groups) in preterm infants compared to non-surgical closure of patent ductus arteriosus (control group). METHODS: Data from preterm infants with patent ductus arteriosus clipping (surgery) via a left postero-lateral thoracotomy were compared with infants in whom the patent ductus arteriosus closed: spontaneously, with medications or use of an occlusive device (controls). Serial pre- and post-closure plain chest radiographs were randomly reviewed by a reader blinded to the route of closure and up to 1 year following the patent ductus arteriosus closure. RESULTS: Of the total of 196 cases included in the study: 45 of the patent ductus arteriosus closed following treatment with medications, 8 cases closed with an occlusion device, 38 were closed surgically, and in 105 cases, the patent ductus arteriosus closed spontaneously. Compared to the pre-operative period, 36/38 (95%) infants in the surgery group had one or more of the following rib abnormalities: ipsilateral fourth and fifth rib fusion, narrowing of the ipsilateral fifth intercostal space, thinning of the ipsilateral fourth or fifth rib, or a combination of the above on the chest radiograph compared to 0% in the control group (p < 0.001). CONCLUSION: Radiographic rib abnormalities are common and appear in infancy following surgical clipping of patent ductus arteriosus in preterm infants. Further studies are needed to clarify the natural history of these abnormalities on thoracic cage and cardiopulmonary functions.