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

Plumb, Andrew A., Phillips, Peter ORCID logo ORCID: , 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: 12 Jan 2024 18:02


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