Increasing navigation speed at endoluminal CT colonography reduces colonic visualization and polyp identification

Plumb, Andrew A., Phillips, Peter, Spence, Graeme, Mallett, Susan, Taylor, Stuart A., Halligan, Steve and Fanshawe, Thomas R. (2017) Increasing navigation speed at endoluminal CT colonography reduces colonic visualization and polyp identification. Radiology, 284 (2). pp. 413-422.

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Purpose: To investigate the effect of increasing navigation speed on the visual search and decision making during polyp identification for computed tomography (CT) colonography.

Materials and Methods: Institutional review board permission was obtained to use deidentified CT colonography data for this prospective reader study. After obtaining informed consent from the readers, 12 CT colonography fly-through examinations that depicted eight polyps were presented at four different fixed navigation speeds to 23 radiologists. Speeds ranged from 1 cm/sec to 4.5 cm/sec. Gaze position was tracked by using an infrared eye tracker, and readers indicated that they saw a polyp by clicking a mouse. Patterns of searching and decision making by speed were investigated graphically and by multilevel modeling.

Results: Readers identified polyps correctly in 56 of 77 (72.7%) of viewings at the slowest speed but in only 137 of 225 (60.9%) of viewings at the fastest speed (P = .004). They also identified fewer false-positive features at faster speeds (42 of 115; 36.5%) of videos at slowest speed, 89 of 345 (25.8%) at fastest, P = .02). Gaze location was highly concentrated toward the central quarter of the screen area at faster speeds (mean gaze points at slowest speed vs fastest speed, 86% vs 97%, respectively).

Conclusion: Faster navigation speed at endoluminal CT colonography led to progressive restriction of visual search patterns. Greater speed also reduced both true-positive and false-positive colorectal polyp identification.

Item Type: Article
Journal / Publication Title: Radiology
Publisher: Radiological Society of North America (RSNA)
ISSN: 1527-1315
Departments: Academic Departments > Medical & Sport Sciences (MSS) > Health and Medical Sciences
Depositing User: Insight Administrator
SWORD Depositor: Insight Administrator
Date Deposited: 21 Mar 2017 09:46
Last Modified: 06 Jul 2021 10:32


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