Head-tracking as an interface device for image control in digital pathology: a comparative study

BACKGROUND: Inasmuch as the conventional mouse is not an ideal input device for digital pathology, the aim of this study was to evaluate alternative systems with the goal of identifying a natural user interface (NUI) for controlling whole slide images (WSI). DESIGN: Four pathologists evaluated three webcam-based, head-tracking mouse emulators: Enable Viacam (eViacam, CREA Software), Nouse (JLG Health Solutions Inc), and Camera Mouse (CM Solutions Inc). Twenty WSI dermatopathological cases were randomly selected and examined with Image Viewer (Ventana, AZ, USA). The NASA-TLX was used to rate the perceived workload of using these systems and time was recorded. In addition, a satisfaction survey was used. RESULTS: The mean total time needed for diagnosis with Camera Mouse, eViacam, and Nouse was 18’57“, 19’37” and 22’32“, respectively (57/59/68 seconds per case, respectively). The NASA-TLX workload score, where lower scores are better, was 42.1 for eViacam, 53.3 for Nouse and 60.62 for Camera Mouse. This correlated with the pathologists’ degree of satisfaction on a scale of 1-5: 3.4 for eViacam, 3 for Nouse, and 2 for Camera Mouse (p< 0.05). CONCLUSIONS: Head-tracking systems enable pathologists to control the computer cursor and virtual slides without their hands using only a webcam as an input device. - Of the three software solutions examined, eViacam seems to be the best of those evaluated in this study, followed by Nouse and, finally, Camera Mouse. - Further studies integrating other systems should be performed in conjunction with software developments to identify the ideal device for digital pathology.