Abstract Archives of the RSNA, 2003


Evaluation of Parameters to Help Develop an Automated Algorithm to Separate a Single CT Acquisition into Grouped Procedures

Scientific Papers

Presented on December 2, 2003
Presented as part of G21: Radiology Informatics (PACS: Tools I)


Eliot Siegel MD, PRESENTER: Nothing to Disclose

Abstract: HTML Introduction: One of the seven original Integrating the Healthcare Enterprise (IHE) protocols addressed the challenge presented by the need to perform a single acquisition of CT images that subsequently must be logically broken into multiple overlapping grouped procedures. Unfortunately this remains a labor intensive manual process. The purpose of this study was to determine whether a computationally simple algorithm based on analysis of image content could be used to automatically identify and separate various anatomic regions on a CT study. Materials and Methods: A total of 1,156 images were evaluated from multiple CT studies which included images from the head, neck, chest, abdomen, and pelvis. A histogram analysis was performed on each image to determine the relative proportions of fat, bone, and soft tissue. Additionally two indices were computed, bone-x and bone-y which are related to the physical distribution pixels that have values in the range of bone on a particular image (e.g. peripheral versus central). Results: Multiple regression analysis of the bone, fat, and soft tissue content of an individual image resulted in high levels of confidence (90-99% depending on anatomic region) for any given axial section. ROC analysis demonstrated that the most useful indices were: bone-y and tissue ratio for the head, tissue area for the neck, air ratio for the thorax, fat ratio for the abdomen, and bone-x and fat ratio for the pelvis. Discussion: We found a high level of accuracy of a combination of multiple indices in the determination of anatomic area for a given CT section. This does not take into account slice position and slice order which could be factored in to the algorithm to markedly increase accuracy through the knowledge that the best predictor of the anatomic region of a given slice is the anatomic location of the previous and subsequent slices. Conclusion: The data suggest that a computationally simple algorithm can be utilized to break a single CT acquisition into multiple grouped procedures. This would be likely to result in substantial time savings for technologists and radiologists in a digital imaging department.     Understand the presentation of grouped procedures IHE integration profile and its limitations. Describe strategies for automating the identification of an individual CT slice with regard to its anatomic location Be able to discuss the advantages of an automated algorithm which can sort individual CT sections into anatomic regions       Questions about this event email: esiegel@umaryland.edu

Cite This Abstract

Siegel MD, E, Reiner MD, B, Evaluation of Parameters to Help Develop an Automated Algorithm to Separate a Single CT Acquisition into Grouped Procedures.  Radiological Society of North America 2003 Scientific Assembly and Annual Meeting, November 30 - December 5, 2003 ,Chicago IL. http://archive.rsna.org/2003/3103510.html