Cai J, Altes T A, Miller G W, Sheng K, Read P W, Mata J F, Zhong X, Cates G D, de Lange E E, Mugler J P, Brookeman J R
Department of Radiation Oncology, University of Virginia School of Medicine, Charlottesville, Virginia 22908, USA.
Magn Reson Med. 2007 Aug;58(2):373-80. doi: 10.1002/mrm.21288.
A new technique is demonstrated in six healthy human subjects that combines grid-tagging and hyperpolarized helium-3 MRI to assess regional lung biomechanical function and quantitative ventilation. 2D grid-tagging, achieved by applying sinc-modulated RF-pulse trains along the frequency- and phase-encoding directions, was followed by a multislice fast low-angle shot (FLASH)-based acquisition at inspiration and expiration. The displacement vectors, first and second principal strains, and quantitative ventilation were computed, and mean values were calculated for the upper, middle, and lower lung regions. Displacements in the lower region were significantly greater than those in either the middle or upper region (P < 0.005), while there were no significant differences between the three regions for the two principal strains and quantitative ventilation (P = 0.11-0.92). Variations in principal strains and ventilation were greater between subjects than between lung zones within individual subjects. This technique has the potential to provide insight into regional biomechanical alterations of lung function in a variety of lung diseases.
在六名健康人体受试者中展示了一种新技术，该技术结合了网格标记和超极化氦 - 3磁共振成像（MRI）来评估局部肺生物力学功能和定量通气。通过沿频率编码和相位编码方向应用 sinc 调制射频脉冲序列实现二维网格标记，随后在吸气和呼气时基于多层快速低角度激发（FLASH）进行采集。计算位移向量、第一和第二主应变以及定量通气，并计算上、中、下肺区域的平均值。下肺区域的位移明显大于中肺或上肺区域（P < 0.005），而三个区域在两个主应变和定量通气方面无显著差异（P = 0.11 - 0.92）。主应变和通气的变化在受试者之间比在个体受试者的肺区域之间更大。该技术有可能深入了解各种肺部疾病中肺功能的局部生物力学改变。
