MRI to quantify early radiation-induced changes in the salivary glands

作者：Houweling Antonetta C; Schakel Tim; van den Berg Cornelis A T; Philippens Marielle E P; Roesink Judith M; Terhaard Chris H J; Raaijmakers Cornelis P J^*

来源：Radiotherapy and Oncology, 2011, 100(3): 386-389.

DOI：10.1016/j.radonc.2011.08.020

• MRI
• Oropharyngeal cancer
• Radiotherapy
• Xerostomia
• DCE-MRI

Purpose: We investigated radiation-induced changes in the salivary glands, 6 weeks after RT, using MRI.
Materials and methods: Eighteen oropharyngeal cancer patients were treated with salivary gland sparing IMRT. All patients received a 31 MRI exam before and 6 weeks after the end of RT, including a T(1)-weighted (T(1)w), a T(2)-weighted (T(2)w), and a dynamic contrast-enhanced (DCE) MRI. For both time points separately, the parotid and submandibular glands were delineated on the MR images. Differences in median signal intensity and signal variation within the glands were tested for significance. Correlations were studied between the MR changes and the planned RI dose.
Results: The volume of the glands reduced significantly by 25%. The T(1)w signal decreased by 10% and the T(2)w signal increased by 23%. The k(ep) value decreased, while the v(e) increased. A correlation of the changes in T(2)w signal with the mean dose was found in both glands.
Conclusions: Overall radiation-induced changes and volume loss were observed in the parotid and submandibular gland using MR. The observed differences indicated an increased water content such as found in oedema. The overall changes could be related to the mean dose, with a slightly greater impact in the high dose area.

• 出版日期2011-9