Colonoscopy video processing for quality metrics determination

• US 7,894,648 B2
• Filed: 06/16/2006
• Issued: 02/22/2011
• Est. Priority Date: 06/17/2005
• Status: Active Grant

• Current Assignee: Iowa State University Research Foundation Incorporated (Iowa State University), Mayo Foundation For Medical Education And Research (Mayo Clinic), Board of Regents of the University of Texas System (University of Texas System)
• Original Assignee: Iowa State University Research Foundation Incorporated (Iowa State University), Mayo Foundation For Medical Education And Research (Mayo Clinic), Board of Regents of the University of Texas System (University of Texas System)
• Inventors: De Groen, Piet C., Oh, Junghwan, Tavanapong, Wallapak, Wong, Johnny
• Primary Examiner(s): Ahmed; Samir A
• Assistant Examiner(s): HU, FRED H.
• Application Number:
  US11/454,561
• Publication Number:
  US 20060293558A1
• Time in Patent Office: 1,712 Days
• Field of Search: 382/128, 348 65- 76, 600100-183
• US Class Current: 382/128
• CPC Class Codes: A61B 1/31 for the rectum, e.g. proctoscopes, sigmoidoscopes , colonoscopes
• CPC Class Codes: G06T 7/0012 Biomedical image inspection

Abstract

A computer-based method that allows automated measurement of a number of metrics that likely reflect the quality of a colonoscopic procedure. The method is based on analysis of a digitized video file created during colonoscopy, and produces information regarding insertion time, withdrawal time, images at the time of maximal intubation, the time and ratio of clear versus blurred or non-informative images, and a first estimate of effort performed by the endoscopist. As these metrics can be obtained automatically, the method allows future quality control in the day-to-day medical practice setting on a large scale. In addition, the method can be adapted to other healthcare procedures. The method may be useful to assess progress during colonoscopy training, or as part of endoscopic skills assessment evaluations.

Claims

1. A system for evaluating objective quality of a colonoscopy procedure performed with an endoscope having a camera, comprising:

an input for receiving information representative of the colonoscopy procedure, including colonoscopy images of the inner lining of a human colon, including colon mucosa;

a processor coupled to the input to process the images of the colon, generate data representative of the colonoscopy procedure, and compute a set of quality metrics representative of the quality of the colonoscopy procedure as a function of the colonoscopy procedure data, the set of quality metrics including;

a) withdrawal time, wherein the withdrawal time is representative of a duration of a withdrawal phase during which the endoscope is withdrawn from the colon, b) clear withdrawal time, wherein the clear withdrawal time is representative of the withdrawal time less a duration of non-informative images, c) number of camera motion direction changes, d) ratio of the number of camera motion direction changes to clear withdrawal time, and e) close-global inspection ratio, wherein the close-global inspection ratio is representative of a ratio of colon wall view images to colon lumen view images; and

an output coupled to the processor for outputting the computed quality metrics.

2. The system of claim 1 wherein:

the processor further generates a rating of the colonoscopy procedure as a function of the set of quality metrics; and

the colonoscopy procedure rating is outputted at the output.

3. The system of claim 1 wherein:

the information representative of the colonoscopy procedure received at the input further includes audio information representative of the location of the endoscope in the colon; and

the processor computes at least some of the quality metrics as a function of the audio information.

4. The system of claim 1 wherein the processor processes the images to identify informative images and non-informative images, and computes one or more of the quality metrics including the clear withdrawal time metric as a function of the informative and non-informative images.

5. The system of claim 1 wherein the processor processes the images to identify a boundary between an endoscope insertion phase and an endoscope withdrawal phase, and computes one or more of the quality metrics as a function of the boundary.

6. The system of claim 1 wherein the processor processes the colonoscopy images to identify segment information representative of oral direction images and anal direction images, and computes one or more of the quality metrics as a function of the segment information.

7. The system of claim 1 wherein:

the processor processes the images to compute informative image information representative of informative images and non-informative images, and computes one or more of the quality metrics as a function of the informative image information;

the processor processes the images to compute boundary information representative of the boundary between an endoscope insertion phase and an endoscope withdrawal phase, and computes one or more of the quality metrics as a function of the boundary information; and

the processor processes the images to compute segment information representative of oral direction images and anal direction images, and computes one or more of the quality metrics as a function of the segment information; and

the processor processes the colonoscopy images to compute lumen information representative of lumen view images and wall view images, and computes one or more of the quality metrics as a function of the lumen information.

8. The system of claim 7 wherein:

the information representative of the colonoscopy procedure includes audio information; and

the processor processes the colonoscopy audio information to compute one or more of the quality metrics.

9. The system of claim 7 wherein:

the processor further generates a rating of the colonoscopy procedure as a function of the set of quality metrics; and

the colonoscopy procedure rating is outputted at the output.

13. The system of claim 1 wherein the processor processes the colonoscopy images to compute lumen information representative of lumen view images and wall view images, and computes one or more of the quality metrics as a function of the lumen information.

10. A system for evaluating objective quality of a colonoscopy procedure performed with an endoscope having a camera, comprising:

an input for receiving information representative of the colonoscopy procedure, including colonoscopy images of the inner lining of a human colon, including colon mucosa;

a processor coupled to the input to process the colonoscopy procedure information, including;

a non-informative frame filtration section to compute informative image information representative of informative images and non-informative images;

a camera motion estimation section to compute boundary information representative of a boundary between an endoscope insertion phase and an endoscope withdrawal phase;

an image segmentation section to compute segment information representative of oral direction images and anal direction images;

a lumen identification section to compute lumen information representative of lumen view images and wall view images; and

a metrics computation section to compute a plurality of quality metrics representative of the quality of the colonoscopy procedure as a function of the informative video information, the boundary information, the segment information, and the lumen information including;

a) withdrawal time, wherein the withdrawal time is representative of a duration of the endoscope withdrawal phase, b) clear withdrawal time, wherein the clear withdrawal time is representative of the withdrawal time less a duration of non-informative images, c) number of camera motion direction changes, d) ratio of the number of camera motion direction changes to clear withdrawal time, and e) close-global inspection ratio, wherein the close-global inspection ratio is representative of a ratio of wall view images to lumen view images; and

an output coupled to the processor for outputting the computed quality metrics.

11. The system of claim 10 wherein the input receives audio information representative of the colonoscopy procedure and the metrics computation section computes one or more of the quality metrics as a function of the audio information.

12. The system of claim 11 wherein:

the processor further generates a rating of the colonoscopy procedure as a function of the plurality of quality metrics; and

the colonoscopy procedure rating is outputted at the output.