Dataset Information

Dedicated cone-beam CT system for extremity imaging.

ABSTRACT:

Purpose

To provide initial assessment of image quality and dose for a cone-beam computed tomographic (CT) scanner dedicated to extremity imaging.

Materials and methods

A prototype cone-beam CT scanner has been developed for imaging the extremities, including the weight-bearing lower extremities. Initial technical assessment included evaluation of radiation dose measured as a function of kilovolt peak and tube output (in milliampere seconds), contrast resolution assessed in terms of the signal difference-to-noise ratio (SDNR), spatial resolution semiquantitatively assessed by using a line-pair module from a phantom, and qualitative evaluation of cadaver images for potential diagnostic value and image artifacts by an expert CT observer (musculoskeletal radiologist).

Results

The dose for a nominal scan protocol (80 kVp, 108 mAs) was 9 mGy (absolute dose measured at the center of a CT dose index phantom). SDNR was maximized with the 80-kVp scan technique, and contrast resolution was sufficient for visualization of muscle, fat, ligaments and/or tendons, cartilage joint space, and bone. Spatial resolution in the axial plane exceeded 15 line pairs per centimeter. Streaks associated with x-ray scatter (in thicker regions of the patient--eg, the knee), beam hardening (about cortical bone--eg, the femoral shaft), and cone-beam artifacts (at joint space surfaces oriented along the scanning plane--eg, the interphalangeal joints) presented a slight impediment to visualization. Cadaver images (elbow, hand, knee, and foot) demonstrated excellent visibility of bone detail and good soft-tissue visibility suitable to a broad spectrum of musculoskeletal indications.

Conclusion

A dedicated extremity cone-beam CT scanner capable of imaging upper and lower extremities (including weight-bearing examinations) provides sufficient image quality and favorable dose characteristics to warrant further evaluation for clinical use.

SUBMITTER: Carrino JA

PROVIDER: S-EPMC4263642 | biostudies-literature | 2014 Mar

REPOSITORIES: biostudies-literature

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Publications

Dedicated cone-beam CT system for extremity imaging.

Carrino John A JA Al Muhit Abdullah A Zbijewski Wojciech W Thawait Gaurav K GK Stayman J Webster JW Packard Nathan N Senn Robert R Yang Dong D Foos David H DH Yorkston John J Siewerdsen Jeffrey H JH

Radiology 20131118 3

<h4>Purpose</h4>To provide initial assessment of image quality and dose for a cone-beam computed tomographic (CT) scanner dedicated to extremity imaging.<h4>Materials and methods</h4>A prototype cone-beam CT scanner has been developed for imaging the extremities, including the weight-bearing lower extremities. Initial technical assessment included evaluation of radiation dose measured as a function of kilovolt peak and tube output (in milliampere seconds), contrast resolution assessed in terms o ...[more]

PMID: 24475803

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Dataset Information

Dedicated cone-beam CT system for extremity imaging.

Purpose

Materials and methods

Results

Conclusion

Publications

Dedicated cone-beam CT system for extremity imaging.

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