Impaired respiratory mechanics in pulmonary emphysema: Evaluation with dynamic breathing MRI

Abstract

To evaluate impaired respiratory mechanics in pulmonary emphysema, dynamic breathing magnetic resonance imaging (BMRI) was acquired with fast-gradient echo pulse sequences at fixed thoracic planes over two to three slow, deep respiratory cycles in 6 controls and 28 patients with pulmonary emphysema including 9 patients undergoing lung volume reduction surgery (LVRS). Respiratory motions of the diaphragm and chest wall (D/CW) were assessed by a cineloop view, a fusion display of maximal inspiratory and expiratory images, and the time-distance curves. By contrast with normal subjects with regular synchronous D/CW motions, the patients frequently showed reduced, irregular, or asynchronous motions, with significant decreases in the maximal amplitude of D/CW motions (MAD and MACW), and the length of apposition of the diaphragm (LAD) (P F 0.0001, P F 0.001, P F 0.01, respectively). After LVRS, nine patients showed improvements in D/CW configuration and mobility, with significantly increased MAD, MACW, and LAD (P F 0.01, P F 0.0001, and P F 0.05, respectively). In 40 studies of 28 patients including the post-LVRS examinations, the normalized MAD and MACW significantly correlated with %FEV 1 (r ‫؍‬ 0.881 and r ‫؍‬ 0.906; P F 0.0001, respectively). BMRI seems useful for noninvasively and directly assessing the impaired respiratory mechanics associated with abnormal ventilation in pulmonary emphysema, and also for monitoring the effects of LVRS. J. Magn. Reson. Imaging 1999;10:510-520. 1999 Wiley-Liss, Inc. Index terms: lung; dynamic magnetic resonance (MR) imaging; pulmonary emphysemaAbbreviations: BMRI, breathing magnetic resonance imaging; D/CW, diaphragm and/or chest wall; MAD, maximal amplitude of respiratory motions of the diaphragm; MACW, maximal amplitude of respiratory motions of the chest wall; RM, respiratory muscle; LVRS, lung volume reduction surgery; PFT, pulmonary function test; SPECT, single-photon emission computed tomography; TDC, time-distance curve.

Pulmonary Magnetic Resonance Imaging for Airway Diseases

“…78,79 In addition to volumetric MDCT, dynamic MR imaging using several MR sequences was recommended for a complementary role in the assessment of chest wall, diaphragm, and lung motion without ionizing radiation exposure and has been used since 1995 (Fig. [80][81][82][83][84][85][86][87] At present, the easiest method of assessing chest wall and diaphragm motion, which are different for normal individuals and for patients with airway diseases, involves the use of 2-dimensional or 3-dimensional dynamic MR imaging combined with turbo SE, T1-weighted GRE, or steady-state sequences. [80][81][82][83][84][85][86][87] At present, the easiest method of assessing chest wall and diaphragm motion, which are different for normal individuals and for patients with airway diseases, involves the use of 2-dimensional or 3-dimensional dynamic MR imaging combined with turbo SE, T1-weighted GRE, or steady-state sequences.…”

“…13). [80][81][82][83][84][85][86][87] In addition, quantitative analysis of dynamic MR imaging using an isotropic time-resolved 3-dimensional GRE sequence combined with view sharing and parallel imaging techniques has made it possible to assess tumor volume and rotation in the respiratory cycle. [80][81][82][83][84][85][86][87] In addition, quantitative analysis of dynamic MR imaging using an isotropic time-resolved 3-dimensional GRE sequence combined with view sharing and parallel imaging techniques has made it possible to assess tumor volume and rotation in the respiratory cycle.…”

Imaging tumour motion for radiotherapy planning using MRI

“…Novel MRI techniques allow for non-invasive acquisition of the motion of lung and pulmonary tumours [7] during the respiratory cycle with high spatial and temporal resolution [8, 9]. Continuous improvements and new developments in MR scanner technology, such as high performance gradient systems and pulse sequences, have made this possible and address the inherent challenges of MRI of the chest, such as low proton density with an unfavourable signal to noise ratio and short T2 * relaxation times with substantial susceptibility artefacts.…”

“…changes of the cranio-caudal distance before and after lung volume reduction surgery [7]. The results exhibited a good correlation with spirometry.…”

Advanced Algorithmic Approaches to Medical Image Segmentation

“…Other fast imaging methods include: dynamic contrast-enhanced breast MRI done using twoand three-dimensional variable flip angle fast low-angle shot Tl measurement (see Brookes et al [35]); dynamic-breathing MRI (see Suga et al [36]) ; ultrafast MRI (see Outwater [37]); hepatic lesion fat suppressed T2-weighted MR imaging pulse sequence (see Kanematsu et al [38]); coronary MR angiography (see Duerinckx [39]); fast-FLAIR MTC pulse sequence (see Filippi [40]); Single Shot Fast Spin Echo (SSFSE) pulse sequence (see Kadoya et al [41]); Fast Spin Echo Diffusion Coefficient Mapping MRI (see Brockstedt et al [42]); adiabatic multiple Spin Echo pulse sequence (see Zweckstetter et al [43]); half-Fourier TUrbo Spin Echo MRI (HASTE12) (see Coates et al [44]) ; 3-D Time of Flight MR angiography by Ultrafast MP-RAGE sequence (see Yamashita et al [45]); Coherent and Incoherent steady-state spin-echo (COSESS 13 and INSESS 14 ) sequences (see Werthner et al [46]) ; phase-modulated binominal RF pulses for spectrally selective imaging (see Thomasson et al [47]) ; Dual Echo Steady-State Free Precession (DESS-FP) pulse sequence (see Hardy et al [48]); optimized ultra-Fast Imaging Sequence (OUFIS) (see Zha et al [49]) ; fast three -dimensional Inversion-Recovery GRE pulse sequence (see Foo et al [50]); diffusion-weighted EPI pulse sequences for glioma (see Tien et al [51]) ; Time of Flight carotid vascular contrast MRA pulse sequences (see Tkach et al [52]); incremental Flip Angle Snapshot FLASH MRI pulse sequence (see Urhahn et al [53]); Steady-State Free Precession Rapid 2-DFT MRI: FAST and CE-FAST sequences (see Gyngell [54]). …”