Avoiding skull radiographs in infants with suspected inflicted injury who also undergo head CT: “a no-brainer?”

Abstract

Objectives To assess whether head CT with 3D reconstruction can replace skull radiographs (SXR) in the imaging investigation of suspected physical abuse (SPA)/abusive head trauma (AHT). Methods PACS was interrogated for antemortem skeletal surveys performed for SPA, patients younger than 2 years, SXR and CT performed within 4 days of each other. Paired SXR and CT were independently reviewed. One reviewer analysed CT without and (3 months later) with 3D reconstructions. SXR and CT expert consensus review formed the gold standard. Observer reliability was calculated. Results A total of 104 SXR/CT examination pairs were identified, mean age 6.75 months (range 4 days to 2 years); 21 (20%) had skull fractures; two fractures on CT were missed on SXR. There were no fractures on SXR that were not seen on CT. For SXR and CT, respectively: PPV reviewer 1, 95% confidence interval (CI) 48-82% and 85-100%; reviewer 2, 67-98% and 82-100%; and NPV reviewer 1, 95%, CI 88-98% and 96-100%; reviewer 2, 88-97% and 88-98%. Inter-and intra-observer reliability were respectively the following: SXR, excellent (kappa = 0.831) and good (kappa = 0.694); CT, excellent (kappa = 0.831) and perfect (kappa = 1). All results were statistically significant (p < 0.001). Conclusions CT has greater diagnostic accuracy than SXR in detecting skull fractures which is increased on concurrent review of 3D reconstructions and should be performed in every case of SPA/AHT. SXR does not add further diagnostic information and can be omitted from the skeletal survey when CT with 3D reconstruction is going to be, or has been, performed. Key Points • Head CT with 3D reconstruction is more sensitive and specific for the diagnosis of skull fractures. • Skull radiographs can be safely omitted from the initial skeletal survey performed for suspected physical abuse when head CT with 3D reconstruction is going to be, or has been, performed.

A comparison of computed tomography, X‐ray and Lodox® scans in assessing pediatric skull fractures using piglets

“…The sensitivity for X‐rays was only slightly lower than that reported by Cattaneo et al [8], where X‐rays detected only a third of all pediatric skull fractures. Sensitivities for CTs and X‐rays in the present study were also lower than those reported by Martin et al [12] who found sensitivities of 81% for CTs and 77‐81% for X‐rays, and Culotta et al [5] who cited a 97% sensitivity for CTs and 90% for X‐rays. However, both authors used either the CT or X‐ray scans as the gold standard, not osteological analysis.…”

“…In addition, most temporal fractures, and many parietal and frontal fractures close to the vertex of the skull, such as the parietal fracture seen in Figure 1, were undetected using X‐rays and Lodox ® . The low sensitivities for detecting skull fractures in the correct locations may, in the case of CTs, be the result of the orientation of the scan slice with respect to that of the fracture [8,12]. In the case of X‐rays and Lodox ® scans, superimposition of bones, very thin or incomplete fractures, and the limited three‐views of the skull (anteroposterior and left and right lateral) may limit the detectability of fractures and cause the underestimation of the number of fractures present [4,7,8,24].…”

“…In the case of X‐rays and Lodox ® scans, superimposition of bones, very thin or incomplete fractures, and the limited three‐views of the skull (anteroposterior and left and right lateral) may limit the detectability of fractures and cause the underestimation of the number of fractures present [4,7,8,24]. Since CT scans have the highest sensitivity for detecting fractures at the correct location, children with suspected cranial fractures should undergo CT scans where possible rather than X‐rays and Lodox ® , which are insensitive and add no diagnostic value over CTs, a recommendation also made by a number of other authors [3,4,12]. Moreover, CT scans have the additional advantage of visualizing intracranial injury and trauma [5,12].…”

“…Some studies have assessed the diagnostic accuracy of these imaging tools in detecting fractures in pediatric patients and have found that CT scans identified more fractures than X‐rays, and that many fractures identified by X‐rays were false‐positives [3,12]. In a study of 85 pediatric patients with skull fractures, CT scans were found to be more sensitive than X‐rays in identifying linear, depressed, and diastatic skull fractures [4].…”

“…Some studies have assessed the diagnostic accuracy of these imaging tools in detecting fractures in pediatric patients and have found that CT scans identified more fractures than X-rays, and that many fractures identified by X-rays were false-positives [3,12].…”