Introduction: Salivary gland obstructive conditions are common and may necessitate imaging of the glands for diagnosis and management purposes. Many imaging options are available but all have limitations. Sialography is considered the gold standard for examining obstructive conditions of the parotid and submandibular glands but it is largely influenced by the imaging technique to which it is coupled. Cone beam computed tomography (cbCT) is a relatively new and very promising imaging modality that has overcome many of the inherent limitations of other imaging modalities used in the past for sialography. Materials and methods: A RANDO®Man imaging phantom was used to determine the effective radiation doses from the series of plain film images that represent the current standard of practice for sialography. Similar experiments were then undertaken to determine the effective radiation doses from cbCT when varying the field-of-view (FOV) size and center, x-ray tube peak kilovoltage (kVp) and milliamperage (mA). Next, cbCT image quality, measured using the signal-difference-to-noise-ratio (SDNR) was used to determine those technical factors that optimized image quality. Finally, using the optimized image acquisition parameters, a prospective clinical study was conducted to test the diagnostic efficacy of cbCT sialography compared to plain film sialography. Results: Effective radiation doses were comparable between the plain film image series and cbCT examinations of the parotid and submandibular glands when a 6” FOV was chosen, and when the x-ray tube was operating at 80 kVp and 10 mA. We also found that these exposure settings optimized the image SDNR. Finally, we demonstrated that the diagnostic capabilities of cbCT sialography were superior to plain film sialography with regards to detecting sialoliths and strictures, and when differentiating normal salivary glands from those with changes secondary to inflammation. Conclusion: We have successfully developed a three dimensional (3D) sialography technique for imaging the parotid and submandibular salivary glands using cbCT that balances radiation effective dose with image quality. We also demonstrated the superior diagnostic capabilities of the new technique in a clinical setting.
| Identifer | oai:union.ndltd.org:TORONTO/oai:tspace.library.utoronto.ca:1807/34065 |
| Date | 13 December 2012 |
| Creators | Jadu, Fatima |
| Contributors | Lam, Ernest W. |
| Source Sets | University of Toronto |
| Language | en_ca |
| Detected Language | English |
| Type | Thesis |
Page generated in 0.0023 seconds