Patient rotation chest X-rays and the consequences of misinterpretation in paediatric radiology.

PURPOSE: We aimed to demonstrate the consequences of rotation on neonatal chest radiographs and how it affects diagnosis. In addition, we demonstrate methods for determining the presence and direction of rotation.

BACKGROUND

Patient rotation is common in chest X-rays of neonates. Rotation is present in over half of chest X-rays from the ICU, contributed to by unwillingness of technologists to reposition new-borns for fear of dislodging lines and tubes. There are six main effects of rotation on supine paediatric chest X-rays: 1) unilateral hyperlucency of the side that the patient is rotated towards; 2) the side 'up' appears larger; 3) apparent deviation of the cardiomediastinal shadow in the direction that the chest is rotated towards; 4) apparent cardiomegaly; 5) distorted cardio-mediastinal configuration; and 6) reversed position of the tips of the umbilical artery and vein catheters with rotation to the left. These effects can cause diagnostic errors due to misinterpretation, including air-trapping, atelectasis, cardiomegaly, and pleural effusions, or disease may be masked. We demonstrate the methods of evaluating rotation with examples, including a 3D model of the bony thorax as a guide. In addition, multiple examples of the effects of rotation are provided including examples where disease was misinterpreted, underestimated or masked.

CONCLUSION

Rotation is often unavoidable in neonatal chest X-rays, especially in the ICU. It is therefore important for physicians to recognise rotation and its effects, and to be aware that it can mimic or mask disease.