The lack of general screening for thoracic aortic aneurysm (TAA) compared to abdominal aortic aneurysm is in part due to the higher costs of CT scan or MRI compared to abdominal ultrasound. Here, we introduce a deep learning method to easily detect TAA from a less expensive imaging modality: a single chest x-ray. We use a two-step approach. First, we use image-to-image translation using conditional generative adversarial network to separate the tissue layers (e.g. bone, lung, ascending/descending aorta). Next, we apply a skeletonization algorithm to compute the diameters of the ascending and descending aorta. We validate this method on a paired CXR and CT dataset and find high agreement between the computed diameter from the CXR and the true diameter from the CT scan. The mean absolute error for all cross section diameters and maximum diameters is 3.58mm and 1.97mm, respectively. In detecting dilation (>35mm), our method achieves an F1 score of 0.87 and Cohen's kappa of 0.75, showing high agreement.
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