Implications of surface-rendered facial CT images in patient privacy.

OBJECTIVE: Three-dimensional and multiplanar reconstruction of CT images has become routine in diagnostic imaging. The technology also facilitates surface reconstruction, in which facial features and, as a result, patient identity may be recognized, leading to risk of violations of patient privacy rights. The purpose of this study was to assess whether volunteer viewers can recognize faces on 3D reconstructed images as specific patients. SUBJECTS AND METHODS: A total of 328 participants were included: 29 patients underwent clinically indicated CT of the maxillofacial sinuses or cerebral vasculature and were also photographed (group A); 150 patients volunteered to have their faces photographed (group B); and 149 observers reviewed the images. Surface-reconstructed 3D images of group A were generated from CT data, and digital photographs of both groups A and B were acquired for a total of 179 facial photographs. Image reviewers were recruited with a web-based questionnaire that required observers to match surface-reconstructed images generated from CT data with randomized digital photographs from among the 179 photographs. Data analyses were performed to determine the ability of observers to successfully match surface-reconstructed images with facial photographs. RESULTS: The overall accuracy among the image observers was approximately 61%. No significant differences were found with regard to sex, age, or ethnicity and accuracy of image observers. CONCLUSION: Image reviewers were relatively poor at even side-by-side matching of patient photographs with 3D surface-reconstructed images. This finding suggests that successful identification of patients using surface-rendered faces may be a relatively difficult task for observers.

Computed tomography assessment of valvular morphology, function, and disease.

Recent advancement in computed tomography angiography (CTA) has enabled the noninvasive delineation of cardiac valves using this method. Although echocardiography is the current standard, CTA is a valuable complementary imaging method to evaluate valvular morphology and function. In addition, CTA may contribute to the assessment of both congenital and acquired valvular heart disease, infectious endocarditis, and postsurgical complications of valve replacement.

MR imaging of the brain in fat embolism syndrome.

Fat embolism syndrome (FES) is an uncommon but serious complication of traumatic injury and is frequently diagnostically challenging. In this paper, the authors present four patients who sustained lower extremity long bone injury and who had a normal Glasgow Coma Scale before orthopedic surgical intervention. However, postoperatively, significant neurological deterioration developed in these patients. While cranial computed tomography (CT) obtained immediately after surgery for acutely altered mental status was negative in two of the four patients, brain magnetic resonance imaging (MRI) demonstrated white and gray matter abnormalities accounting for the impaired neurological status in all cases. MRI findings in conjunction with clinical presentation established the diagnosis in all patients. MRI is indicated in any patient with orthopedic injuries who manifests an unexplained acute alteration in mental status, despite a normal head CT.