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. 2019 Aug;32(4):597-604.
doi: 10.1007/s10278-019-00220-4.

Eye Tracking for Deep Learning Segmentation Using Convolutional Neural Networks

Affiliations

Eye Tracking for Deep Learning Segmentation Using Convolutional Neural Networks

J N Stember et al. J Digit Imaging. 2019 Aug.

Abstract

Deep learning with convolutional neural networks (CNNs) has experienced tremendous growth in multiple healthcare applications and has been shown to have high accuracy in semantic segmentation of medical (e.g., radiology and pathology) images. However, a key barrier in the required training of CNNs is obtaining large-scale and precisely annotated imaging data. We sought to address the lack of annotated data with eye tracking technology. As a proof of principle, our hypothesis was that segmentation masks generated with the help of eye tracking (ET) would be very similar to those rendered by hand annotation (HA). Additionally, our goal was to show that a CNN trained on ET masks would be equivalent to one trained on HA masks, the latter being the current standard approach. Step 1: Screen captures of 19 publicly available radiologic images of assorted structures within various modalities were analyzed. ET and HA masks for all regions of interest (ROIs) were generated from these image datasets. Step 2: Utilizing a similar approach, ET and HA masks for 356 publicly available T1-weighted postcontrast meningioma images were generated. Three hundred six of these image + mask pairs were used to train a CNN with U-net-based architecture. The remaining 50 images were used as the independent test set. Step 1: ET and HA masks for the nonneurological images had an average Dice similarity coefficient (DSC) of 0.86 between each other. Step 2: Meningioma ET and HA masks had an average DSC of 0.85 between each other. After separate training using both approaches, the ET approach performed virtually identically to HA on the test set of 50 images. The former had an area under the curve (AUC) of 0.88, while the latter had AUC of 0.87. ET and HA predictions had trimmed mean DSCs compared to the original HA maps of 0.73 and 0.74, respectively. These trimmed DSCs between ET and HA were found to be statistically equivalent with a p value of 0.015. We have demonstrated that ET can create segmentation masks suitable for deep learning semantic segmentation. Future work will integrate ET to produce masks in a faster, more natural manner that distracts less from typical radiology clinical workflow.

Keywords: Artificial intelligence; Deep learning; Eye tracking; Meningioma; Segmentation.

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Figures

Fig. 1
Fig. 1
Eye-tracking setup. User gaze direction is shown by the red arrow. Eye-tracking hardware (in green oval) sends near-infrared light (yellow arrow) to the user’s eyes, which are reflected back as the corneal reflection (dashed blue arrow). The calibration software is able to calculate from the latter the user’s gaze position (curved purple arrow pointing toward green dot on the monitor to the user’s left) in real time
Fig. 2
Fig. 2
Nonneurological image mask borders of various structures of interest. Eye-tracking mask contours are in green, hand annotation in blue
Fig. 3
Fig. 3
Four examples of meningioma mask border comparisons. Eye-tracking (green) and hand annotation (blue) mask contours are overlaid with the corresponding postcontrast T1-weighted images containing meningiomas
Fig. 4
Fig. 4
Four example predictions from the CNN trained on eye-tracking-generated images. Predicted meningioma pixels are in red. Significant overlap between the predicted masks and the enhancing lesions is evident. Note the false positive pixels in Fig. 4c in the right orbital fat. The algorithm is mistaking the high signal intensity of fat for enhancing meningioma
Fig. 5
Fig. 5
ROC curve. Eye-tracking curve is in green, while hand annotation curve is in red

References

    1. Kundel HL, Nodine CF, Carmody D. Visual scanning, pattern recognition and decision-making in pulmonary nodule detection. Investig Radiol. 1978;13(3):175–181. doi: 10.1097/00004424-197805000-00001. - DOI - PubMed
    1. Kundel HL, Nodine CF, Krupinski EA. Searching for lung nodules. Visual dwell indicates locations of false-positive and false-negative decisions. Investig Radiol. 1989;24(6):472–478. doi: 10.1097/00004424-198906000-00012. - DOI - PubMed
    1. Nodine CF, Kundel HL, Lauver SC, Toto LC. Nature of expertise in searching mammograms for breast masses. Acad Radiol. 1996;3(12):1000–1006. doi: 10.1016/S1076-6332(96)80032-8. - DOI - PubMed
    1. Nodine CF, Krupinski EA. Perceptual skill, radiology expertise, and visual test performance with NINA and WALDO. Acad Radiol. 1998;5(9):603–612. doi: 10.1016/S1076-6332(98)80295-X. - DOI - PubMed
    1. Krupinski EA, Tillack AA, Richter L, Henderson JT, Bhattacharyya AK, Scott KM, Graham AR, Descour MR, Davis JR, Weinstein RS. Eye-movement study and human performance using telepathology virtual slides: implications for medical education and differences with experience. Hum Pathol. 2006;37(12):1543–1556. doi: 10.1016/j.humpath.2006.08.024. - DOI - PubMed

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