Habermann C R, Gossrau P, Kooijman H, Graessner J, Cramer M C, Kaul M G, Reitmeier F, Jaehne M, Adam G
Department of Diagnostic and Interventional Radiology, University Medical Center Hamburg-Eppendorf, Hamburg, Germany.
AJNR Am J Neuroradiol. 2007 Sep;28(8):1547-51. doi: 10.3174/ajnr.A0587.
Our aim was to compare different field strengths monitoring physiologic changes due to oral stimulation of parotid glands by using diffusion-weighted (DW) echo-planar imaging (EPI).
Twenty-seven healthy volunteers were examined with a DW-EPI sequence at 1.5T and 3T before and after oral stimulation with commercially available lemon juice. The b factors used were 0, 500, and 1000 s/mm(2). Apparent diffusion coefficient (ADC) maps were evaluated with a manually placed region of interest including the entire parotid gland. For comparison of results, a Student t test was used on the basis of the mean of the volunteer median values. To compare both field strengths, we calculated the Pearson correlation coefficient (r).
DW-EPI MR imaging visualized the parotid glands of all volunteers. With 1.5T, the mean ADC before stimulation was 1.12 x 10(-3) mm(2)/s +/- 0.08 x 10(-3) mm(2)/s. After stimulation with lemon juice, the ADC increased to 1.18 x 10(-3) mm(2)/s +/- 0.09 x 10(-3) mm(2)/s. For 3T, the ADC before stimulation was 1.14 x 10(-3) mm(2)/s +/- 0.04 x 10(-3) mm(2)/s, with an increase to 1.17 x 10(-3) mm(2)/s +/- 0.05 x 10(-3) mm(2)/s after stimulation. For both field strengths, the increase in ADC after stimulation was significant (P < .001). High correlations between both field strengths were found pre- and poststimulation (r = 0.955, and 0.936, respectively).
DW-EPI MR imaging allows monitoring of physiologic changes due to oral stimulation of parotid glands by using DW imaging with high correlation between 1.5T and 3T.
我们的目的是通过使用扩散加权（DW）回波平面成像（EPI）来比较不同场强下腮腺受口腔刺激时的生理变化监测情况。
27名健康志愿者在饮用市售柠檬汁前后，分别采用1.5T和3T的DW-EPI序列进行检查。使用的b值为0、500和1000 s/mm²。表观扩散系数（ADC）图通过手动放置包括整个腮腺的感兴趣区域进行评估。为比较结果，基于志愿者中位数的均值使用Student t检验。为比较两种场强，我们计算了Pearson相关系数（r）。
DW-EPI磁共振成像显示了所有志愿者的腮腺。在1.5T时，刺激前平均ADC为1.12×10⁻³ mm²/s±0.08×10⁻³ mm²/s。用柠檬汁刺激后，ADC增加到1.18×10⁻³ mm²/s±0.09×10⁻³ mm²/s。在3T时，刺激前ADC为1.14×10⁻³ mm²/s±0.04×10⁻³ mm²/s，刺激后增加到1.17×10⁻³ mm²/s±0.05×10⁻³ mm²/s。对于两种场强，刺激后ADC的增加均具有统计学意义（P <.001）。在刺激前后两种场强之间均发现高度相关性（r分别为0.955和0.936）。
DW-EPI磁共振成像能够通过使用DW成像监测腮腺受口腔刺激时的生理变化，且在1.5T和3T之间具有高度相关性。
