Radiographic Evaluation of Stillbirth: What Does it Contribute?
Swenson EE, Schema LS, McPherson EW.
Department of Medical Genetics Services
Research area: Clinical Research
Background: The Wisconsin Stillbirth Service Program (WiSSP) was established to provide comprehensive stillbirth evaluation and promote research into causes of stillbirth. The WiSSP protocol has always included whole body radiographs. However, as prenatal ultrasound quality has improved, most information previously acquired from radiographs has been obtained prenatally. Several recent stillbirth evaluation protocols have omitted X-rays or limited them to select cases. Using the 2799 cases evaluated through WiSSP, we evaluated the utility of whole body radiographs in making diagnoses in the stillborn population.
Methods: Through a computerized search of the WiSSP data, radiographic anomalies were identified in 517/2032 cases with radiographs. For these 517 cases, radiographs were compared with data including perinatal and family history, clinical examination, photographs, autopsy, placental pathology, and laboratory results to determine what role the radiograph played in assigning cause of fetal death.
Results: 234/517(45%) anomalous radiographs were sufficient to make a diagnosis. 30/2032(1.5%) radiographs resulted in a diagnosis that would otherwise have been missed, and 204/2032 (10.0%) provided confirmation of a diagnosis for an overall diagnostic yield of 11.5%. 197/517(38%) helped identify abnormalities contributing to fetal death. Conditions recognized on radiographs included hydrops(165), skeletal dysplasias(25), Mendelian other than skeletal dysplasias(38), chromosomal(95), sporadic birth defects(116), multiple congenital anomalies(43), and non-genetic conditions such as fetal sepsis(12). Only 16/517(3%) did not help assign cause of death, 15/517(3%) were misleading, and 56/517(11%) were incidental anomalies that did not explain fetal death.
Conclusion: Radiographs are useful for recognizing skeletal dysplasias, other birth defects involving bones, and soft tissue abnormalities. Radiographs provided an overall diagnostic yield comparable to other parts of the stillbirth evaluation and are especially valuable in the absence of autopsy and photographs. With the possible exception of cases where a definitive cause of death is known immediately, radiographs should remain a routine part of stillbirth evaluation.