A study of optimization of MRI image examination in salivary gland diseases

2002 Fiscal Year Final Research Report Summary

• Project/Area Number: 13671989
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Single-year Grants
• Section: 一般
• Research Field: 病態科学系歯学(含放射線系歯学)
• Research Institution: Osaka Dental University
• Principal Investigator: KOSEKI Takakazu Osaka Dental Univ., Dentistry, Assistant professor, 歯学部, 講師 (40121818)
• Co-Investigator(Kenkyū-buntansha): INOUE Mashiro Osaka Dental Univ., Dentistry, Assistant professor, 歯学部, 助教授 (50159993) ; HAYASHI Yasuhisa Osaka Dental Univ., Dentistry, Assistant professor, 歯学部, 助手 (90164970)
• Project Period (FY): 2001 – 2002
• Keywords: MRI / MR-sialography / Sialography / Sonography / Parotid gland / Submandibular gland / Salivary gland tumor / Sjogren's syndrome

Research Abstract

The disorders of the salivary glands and its circumference are one of the diseases that we need a lot of information in addition to image examination to diagnose correctly. A purpose of image examination is different by the kind of a lesion. For one example, in case of tumor nature lesion, it is important to exam a position of a lesion, a bad degree and relation of a position with a blood vessel and the nervous system. For another, in case of inflammation and autoimmune disease, a change of a salivary glands organization and a function of that become important point of an examination. Examination of MR imaging is the method that is necessary for image examination of a disorder to appear in salivary glands and the circumference disorders. I suggest optimization of MR for image examination by making an examination procedure of a disorder to appear in salivary glands and the circumference clear. First arranging and integrate information of the image characteristic of each disorder. Then a utomating calculation such as statiscal manifestation frequency or conformity rate of a disorder so long as possible.
The purpose of these works is helping your image diagnosis. For a disorder to appear in a salivary glands and the circumference, carried out sonography before MR image examination, and judged a tumor nature or inflammation nature lesion, and an inflammation nature lesion did an Axial image (T1, T2, T2-fat), and added a Coronal image (T1) on the occasion of tumorous lesion about optimization of image examination in a principle. In this study, I focus the examination that did not increase inversion of contrast medium. I took normal salivary glands (parotid gland: 89 glands, submandibular gland: 82 glands) and settled tumorous lesion (41 cases), inflammatory lesions (67 cases) and autoimmune disease of diagnosis as an object of study. It became possible to limit a liquid ingredient of high signal domain of T2 image more by adding T2-fat suppression and on a disorder intended for this time, the effectiveness was high. Especially, for Sjogren's syndrome and metastases to lymph nodes case the examination became possible that precision was high by T2-fat.
On MR-sialography, while it was advantageous that I could observe form any kind of direction with 3D image (MIP), the search of the salivary glands was high of an image of 1 slice of 20mm when the signals were weak. As a result, I decide that I use 3D image (MIP) for the tumorous lesions and the image of 1 slice of 20mm for inflammatory lesions. I thought about the use of a diffusion image as means to keep objectivity in image information, but because a use period was limited, then I switched the policy. I considered the image factor that seems to be useful for discrimination diagnosis from a saved image. I expressed equality of the image of the each pixel signal strength of the salivary glands and lesion parts did not receive influence such as window width or level very much. In sjorgren's syndrome, I had a meaningful difference between normal salivary glands and sialoadenitis. I could take advantage of it as an index of a discrimination diagnosis. There were a few cases, but it was expected that we could use it for discrimination of an inflammatory lymph node and metastasis lymph node.