磁共振快速成像技术在肺癌分期中的应用

目的:探讨MRI快速成像序列在肺癌分期中的成像质量及其临床应用价值。方法:36例肺癌患者,分别行MRI快速序列成像及CT增强扫描。分析快速序列的伪影,与CT对比分析肿瘤与胸部邻近结构的关系、淋巴结肿大情况。结果:HASTE各项伪影评分均为0,FLASH伪影也低于常规序列。FLASH和true FISP无呼吸伪影,但搏动伪影高于常规序列。与CT对比,在显示胸部邻近结构侵犯方面,HASTE效果可靠,FLASHt、rueFISP因不同程度受伪影影响而效果次之。HASTE和FLASH均可显示纵隔肿大淋巴结。结论:HASTE无伪影,可作为肺癌MRI分期的首选快速成像序列,FLASH则主要用于冠状位成像,trueFISP可以选择应用。     

Ultrafast MR imaging of the normal posterior fossa in fetuses

OBJECTIVE: The purpose of our study was to determine if a standard imaging protocol using ultrafast MR sequences could adequately reveal normal posterior fossa anatomy in fetuses and, if so, to document a template on MR imaging for normal posterior fossa development. MATERIALS AND METHODS: A retrospective review found 66 MR imaging studies of 63 fetuses, 16-39 weeks' gestation age (mean, 25 weeks' gestation), who were referred between June 1996 and May 1999 for evaluation of non-central nervous system anomalies revealed on prenatal sonography. All fetuses had normal brains and spines on prenatal sonography. The standard MR imaging protocol included axial, sagittal, and coronal half-Fourier acquisition single-shot turbo spin echo (HASTE); sagittal and coronal two-dimensional fast low-angle shot (FLASH); and axial turbo T1-weighted FLASH images through the fetal brain. Structures that we analyzed were the fourth ventricle, the cisterna magna, the vermis, the cerebellar hemispheres, and the brainstem. Using the HASTE sequences, we documented gestational age-specific signal intensity changes in the cerebellar hemispheres and the brainstem. RESULTS: The posterior fossa anatomy was sufficiently well defined to exclude abnormalities of the fourth ventricle and cerebellar vermis in all cases. Because of high T2-weighting, good contrast enhancement, and good signal-to-noise ratios, HASTE images provided the best anatomic definition of the posterior fossa. CONCLUSION: Normal posterior fossa anatomy can be adequately shown on ultrafast MR images, which can be helpful when prenatal sonography is equivocal.     

MRI快速扫描技术在儿童先天性心脏病诊断中的应用

目的:探讨MRI半傅立叶采集单次激发快速SE(HASTE)序列、真稳态进动快速成像(TrueFISP)序列和并行采集技术在儿童先天性心脏病诊断中的应用价值.方法:对50例经超声心动图检查的先天性心脏病患儿进行心脏大血管MRI检查,其中26例行DSA检查,全部病例经手术证实.扫描序列包括HASTE、TrueFISP序列以及回顾性心电门控心血管电影成像,并加用并行采集技术.分析各序列MRI图像质量,并将MRI检查结果与超声心动图、DSA结果进行对照.结果:MRI共检出10种复杂先心共181处心血管畸形.26例行DSA检查共检出畸形120个并均与手术结果吻合,MRI显示畸形114个(95.00%),超声心动图检出畸形110个(92.67%).TrueFISP序列和HASTE序列利于显示血管畸形,电影序列有助于检出心内外分流.结论:HASTE黑血技术、TrueFISP亮血技术结合快速电影序列进行心脏MRI检查,可以获得高质量的图像以及较高的病变检出率,适用于儿童先天性心脏病的诊断.     

Usefulness of segmented trueFISP cardiac pulse sequence in evaluation of congenital and acquired adult cardiac abnormalities

OBJECTIVE: The purpose of this study is to compare ultrashort TR, segmented trueFISP (fast imaging with steady-state precession) cine MR imaging with segmented FLASH (fast low-angle shot) cine MR imaging for the detection and characterization of congenital and acquired adult cardiac abnormalities. SUBJECTS AND METHODS: Twenty-five patients with known or clinically suspected cardiac abnormalities were imaged on a 1.5-T scanner. Valve plane movies were obtained in patients with suspected valve morphology or function abnormalities or whose horizontal long-axis images showed jets. For each patient, three radiologists independently compared corresponding matched cine FLASH and trueFISP movies for image quality in evaluating anatomy and function of the great vessels and heart. Image quality was rated on a five-point scale, and data were analyzed using both a Wilcoxon's signed rank test and a repeated-measures analysis of variance. RESULTS: Image quality ratings of trueFISP and FLASH showed a statistically significant difference (F = 58.67; df = 1, 72; p < 0.0001), with the average rating for the trueFISP images being significantly higher (mean rating, 4.1 +/- 0.92) than that for the FLASH images (mean, 3.0 +/- 1.0). However, valve architecture in the aortic valves appeared to be better visualized and was more easily measured in valve plane images with FLASH. No statistically significant differences among the ratings of the interpreters (F = 0.018; df = 2, 72; p = 0.9821) were evident, and, therefore, no suggestion of bias was indicated (F = 0.775; df = 1, 2; p = 0.4645). TrueFISP yielded the correct diagnosis prospectively in 13 (100%) of 13 patients, whereas FLASH yielded the correct diagnosis in 12 (92%) of 13 patients. CONCLUSION: TrueFISP images depict morphologic and functional abnormalities with greater clarity and provide greater diagnostic confidence than FLASH images-and in a fraction of the time. A specific exception is in the assessment of valve leaflet architecture and cross-sectional area calculation (i.e., bicuspid aortic valves); in these evaluations, FLASH maintains a complementary diagnostic imaging role.     

Single-shot inversion recovery TrueFISP for assessment of myocardial infarction

OBJECTIVE: The aim of the study was to assess the diagnostic accuracy of imaging the myocardium with a fast multislice inversion recovery 2D single-shot true fast imaging with steady-state precession (trueFISP) sequence during a single breath-hold in comparison with an established segmented inversion recovery turbo fast low-angle shot (turboFLASH) sequence. SUBJECTS AND METHODS: Forty-three patients with myocardial infarction were examined on a 1.5-T MR system 10 min after administration of contrast material (gadodiamide, 0.2 mmol/kg) with a single-shot 2D multislice technique (single-shot inversion recovery trueFISP) that allows one to image the entire short axis during one breath-hold (18 heartbeats) and with a segmented 2D single-slice technique (inversion recovery turboFLASH) that requires one breath-hold per slice (12 heartbeats). Signal intensity was determined in normal myocardium, in infarcted myocardium, and in the left ventricle. The contrast-to-noise ratio (CNR) of normal and infarcted myocardium was determined. The areas of hyperintense infarctions on selected slices and the entire volumes were compared for both sequence techniques. RESULTS: The inversion recovery trueFISP sequence has a lower CNR than the inversion recovery turboFLASH sequence (mean values, 10.0 vs 12.9, respectively; p = 0.005) for differentiation of viable from nonviable myocardium. The CNR of injured myocardium and blood in the left ventricular cavity also has a lower value for the multislice technique compared with the single-slice technique (0.6 vs 1.2, respectively; p = 0.045). Assessment of the area of infarction within one slice (r = 0.97, p < 0.002) and of the volume of the entire infarction (r = 0.96, p < 0.003) is possible with excellent correlation of both techniques. CONCLUSION: Despite having a lower CNR, the inversion recovery 2D single-shot trueFISP sequence allows fast and accurate identification of the area and volume of infarction with high spatial resolution within a single breath-hold.     

MR colonography with fecal tagging: comparison between 2D turbo FLASH and 3D FLASH sequences

The objective of this study was to compare inversion recovery turbo 2D fast low-angle shot (FLASH) and 3D FLASH sequences for fecal-tagged MR colonography studies. Fifteen consecutive patients with indications for colonoscopy underwent MR colonography with fecal tagging. An inversion recovery turbo-FLASH sequence was applied and compared in terms of artifacts presence, efficiency for masking residual stool, and colonic wall conspicuity with a fat-saturated 3D FLASH sequence. Both sequences were acquired following administration of paramagnetic contrast agent. Contrast-to-noise ratio and relative contrast between colonic wall and lumen were calculated and compared for both sequences. Turbo 2D FLASH provided fewer artifacts, higher efficiency for masking the residual stool, and colonic wall conspicuity equivalent to 3D FLASH. An inversion time of 10 ms provided homogeneously low signal intensity of the colonic lumen. Contrast to noise between colonic wall and lumen was significantly higher in the 3D FLASH images, whereas differences in relative contrast were not statistically significant. An optimized inversion-recovery 2D turbo-FLASH sequence provides better fecal tagging results and should be added to the 3D FLASH sequence when designing dark-lumen MR colonography examination protocols. Electronic Publication     

Uterine peristalsis: comparison of transvaginal ultrasound and two different sequences of cine MR imaging

PURPOSE: To compare uterine peristalsis as seen on two different magnetic resonance (MR) imaging sequences and transvaginal ultrasound (TVUS), so as to better determine the best method for evaluating uterine peristalsis. MATERIALS AND METHODS: Eleven women in the periovulatory phase of the menstrual cycle underwent TVUS and cine MR imaging within a time period of three hours. Findings on cine MR images obtained with a serial 60 half-Fourier acquisition single-shot turbo spin-echo (HASTE) sequence and a 300 true fast imaging with steady-state precession (FISP) sequence were compared with TVUS. RESULTS: The image quality of the HASTE technique was the best among the three methods, followed by TVUS, and then true FISP technique (P < 0.001). Uterine peristalsis was detected in 100% of subjects using HASTE, 82% with True FISP, and 100% with TVUS. With HASTE technique, true FISP, and TVUS, respectively, endometrial stripping movement was identified in 100%, 82%, and 100%; direction was identified in 100%, 45% (P = 0.014), and 73%; and wave conduction toward the outer myometrium was identified in 55%, 9% (P = 0.025), and 0% (P = 0.014). CONCLUSION: Cine MR imaging by HASTE technique with a time resolution of two seconds best delineated uterine peristalsis compared to that by true FISP technique or with TVUS.     

HASTE sequence and cine-MRI evaluation of the cervical spinal canal: evaluation in 11 healthy subjects

PURPOSE: We studied 11 healthy subjects were evaluated using cine MR imaging comparing HASTE and gradient echo sequences. Materials and methods :HASTE is a high-speed turbo-spin echo T2-weighted sequence. All examinations were performed using dynamic MRI using a simple process allowing acquisition of images at different stages during flexion and extension. The cine MR evaluation was obtained by rebuilding a cine-loop sequence. RESULTS: HASTE sequence provides a myelographic effect of the cervical spine. The size, the pattern and the movements of the cervical spine, the spinal cord, as well as the functional reserve of cerebro-spinal fluid are analysable. CONCLUSION: Because of its very high speed, HASTE sequence is particularly useful for cine MR imaging.     

MR imaging of focal lung lesions: elimination of flow and motion artifact by breath-hold ECG-gated and black-blood techniques on T2-weighted turbo SE and STIR sequences.

Respiratory and cardiac motion correction may result in better turbo spin-echo (SE) imaging of the lung. To compare breath-hold cardiac-gated black-blood T2-weighted turbo SE and turbo short-inversion-time inversion-recovery (STIR) magnetic resonance (MR) imaging pulse sequences with conventional breath-hold turbo SE and half-Fourier acquisition single-shot turbo spin-echo (HASTE) sequences for lesion conspicuity of focal lung lesions, 42 patients with focal lung lesions were prospectively studied with MR imaging at 1.5 T. Helical computed tomography was used as a reference. In comparison with the conventional breath-hold turbo SE sequence, all black-blood sequences had fewer image artifacts arising from the heart and blood flow. The overall image quality for the black-blood turbo SE and turbo STIR sequences was superior to that for the breath-hold turbo SE and HASTE sequence (P < 0.01). Not only focal lung lesions but also surrounding inflammatory changes were clearly visualized with these two sequences. With the HASTE sequence, although several slices could be obtained in one breath-hold, both the tumor and vessels appeared blurred. We conclude that T2-weighted turbo SE and turbo STIR imaging of the lung with effective suppression of flow and motion artifacts provide high-quality images in patients with focal lung lesions.     

Centrically reordered inversion recovery half-Fourier single-shot turbo spin-echo sequence: improvement of the image quality of oxygen-enhanced MRI

PURPOSE: The purpose of the study presented here was to determine the improvement in image quality of oxygen-enhanced magnetic resonance (MR) subtraction imaging obtained with a centrically reordered inversion recovery half-Fourier single-shot turbo spin-echo (c-IR-HASTE) sequence compared with that obtained with a conventional sequentially reordered inversion recovery single-shot HASTE (s-IR-HASTE) sequence for pulmonary imaging. MATERIALS AND METHODS: Oxygen-enhanced MR imaging using a 1.5 T whole body scanner was performed on 12 healthy, non-smoking volunteers. Oxygen-enhanced MR images were obtained with the coronal two-dimensional (2D) c-IR-HASTE sequence and 2D s-IR-HASTE sequence combined with respiratory triggering. For a 256x256 matrix, 132 phase-encoding steps were acquired including four steps for phase correction. Inter-echo spacing for each sequence was 4.0 ms. The effective echo time (TE) for c-IR-HASTE was 4.0 ms, and 16 ms for s-IR-HASTE. The inversion time (TI) was 900 ms. To determine the improvement in oxygen-enhanced MR subtraction imaging by c-IR-HASTE, CNRs of subtraction image, overall image quality, and image degradation of the c-IR-HASTE and s-IR-HASTE techniques were statistically compared. RESULTS: CNR, overall image quality, and image degradation of c-IR-HASTE images showed significant improvement compared to those s-IR-HASTE images (P<0.05). CONCLUSION: Centrically reordered inversion recovery half-Fourier single-shot turbo spin-echo (c-IR-HASTE) sequence enhanced the signal from the lung and improved the image quality of oxygen-enhanced MR subtraction imaging.     

建立标准节段磁共振心肌灌注成像方法的初步研究

目的探讨采用快速单次激发梯度回波序列（turbo FLASH）加并行采集技术（iPAT）行心肌MR灌注成像获得标准节段的可行性。资料与方法对6名健康志愿者及5例经心电图和冠状动脉造影证实心肌缺血患者采用turbo FLASH加iPAT心肌MR灌注成像,将3层定位于标准短轴位,另外2层分别定位为垂直长轴和水平长轴位。结果全部受试者均完成检查。3层短轴位加垂直长轴和水平长轴位图像能获得整个左心室心肌灌注图像,满足心肌标准17个节段分段。于3例心肌缺血患者中观察到心肌低灌注区。结论采用turbo FLASH序列加iPAT同时行短轴位以及垂直长轴和水平长轴位心肌MR灌注成像是可行的,获得图像能覆盖左心室心肌17个标准节段．可以用于MR心肌灌注成像全面评价左心室心肌灌注状态。     

MR sialography using half-Fourier acquisition single-shot turbo spin-echo (HASTE) sequences.

We describe our preliminary experience with the half-Fourier acquisition single-shot turbo spin-echo (HASTE) sequences for MR imaging of the salivary gland ducts. In the majority of patients, the main parotid and/or submandibular gland ducts and large branches within the glands were detectable on MR images obtained in 2 seconds per section and within 3 minutes for the entire examination. MR sialography using HASTE sequences can be combined with conventional MR studies for the salivary glands.     

Effectiveness of MR imaging for diagnosing the mild forms of acute pancreatitis: comparison with MDCT

PURPOSE: To assess the usefulness of MRI and determine which MR sequence is most effective for diagnosing the mild forms of acute pancreatitis. MATERIALS AND METHODS: Forty subjects (20 normal volunteers and 20 patients with a mild form of acute pancreatitis) underwent MRI with fat-suppressed T1-weighted fast low-angle shot (FLASH), half-Fourier acquisition single-shot turbo spin-echo (HASTE), and TSE short TI inversion recovery (TSE-STIR) sequences. The 20 patients with a mild form of acute pancreatitis underwent multidetector CT (MDCT) and MRI within a 24-hour interval. We qualitatively analyzed all of the images by assessing inflammatory changes in the pancreas and peripancreatic fat. We quantitatively compared differences in pancreas-liver contrast between the control and patient groups for each MR sequence by measuring the signal intensities of the pancreas and liver. RESULTS: TSE-STIR was the best of the four modalities for delineating peripancreatic and pancreatic inflammation (P < 0.01). TSE-STIR depicted definitive peripancreatic and pancreatic inflammation in 18 and 15 patients, respectively. MDCT depicted only three cases of peripancreatic inflammation. TSE-STIR was also produced the best the best quantitative results of the MR sequences (P = 0.09). CONCLUSION: MRI is helpful for diagnosing the mild forms of acute pancreatitis. We recommend the use of TSE-STIR imaging as part of the routine protocol for evaluating pancreatitis.     

Cardiac function: MR evaluation in one breath hold with real-time true fast imaging with steady-state precession

In 12 healthy volunteers and eight patients with cardiac disease, cine magnetic resonance (MR) imaging in the heart was performed with real-time true fast imaging with steady-state precession (FISP), which permitted evaluation of the entire left ventricle in one breath hold (91 msec per frame, 13 frames per section position, nine short-axis section positions per breath hold). Contrast-to-noise ratios (CNRs) and left ventricular mass and function measurements with this technique were compared in all subjects with single-section true FISP imaging and, in the volunteers only, with segmented fast low-angle shot (FLASH) MR imaging. Myocardium-to-blood CNR was significantly higher for both true FISP sequences compared with the FLASH sequence. Measurements of resting left ventricular function with real-time true FISP imaging were comparable with those derived from a series of separate breath-hold single-section true FISP acquisitions.     

MRI of the lung: value of different turbo spin-echo, single-shot turbo spin-echo, and 3D gradient-echo pulse sequences for the detection of pulmonary metastases

PURPOSE: To compare the value of different MRI sequences of the lung for the detection of pulmonary metastases. MATERIALS AND METHODS: A total of 28 patients with 225 pulmonary metastases confirmed at multidetector-row computed tomography (MDCT) underwent MRI of the lung, including breathhold T2-weighted single-shot turbo spin-echo (half-Fourier single-shot turbo spin-echo [HASTE] and inversion recovery [IR]-HASTE) and conventional turbo spin-echo (TSE and short-tau inversion recovery [STIR]) sequences, a respiratory- and pulse-triggered black-blood STIR sequence (triggered STIR), and breathhold pre- and postcontrast volumetric interpolated 3D gradient-echo (VIBE) sequences. MR images were reviewed by three independent observers and results were correlated with MDCT, which served as standard of reference. Lesion-to-lung contrast-to-noise ratios (CNRs) and image artifacts were also assessed. RESULTS: CNRs were highest on TSE images (P < 0.001). Mean sensitivities for lesion detection with triggered STIR, TSE, and STIR were 72.0%, 69.0%, and 63.4%, respectively. With HASTE, IR-HASTE, and pre- and postcontrast VIBE, significantly lower sensitivities were obtained (P < 0.05), although artifacts due to physiological motion were less distinct with these sequences compared to TSE and STIR (P < 0.05). CONCLUSION: Conventional TSE sequences are more sensitive in depicting pulmonary metastases than single-shot TSE or 3D gradient-echo sequences. Respiratory and pulse triggering can improve lesion detection, but increases acquisition time substantially.     

Incremental flip angle snapshot FLASH MRI of hepatic lesions: improvement of signal-to-noise and contrast.

Incremental flip angle (IFA) snapshot fast low angle shot (FLASH) is a new modification of inversion recovery snapshot FLASH MR imaging. The method changes the flip angle incrementally from low to high during data acquisition and was applied in the evaluation of 16 focal hepatic lesions in 10 patients. Sequence comparisons were performed with a fixed flip angle inversion recovery snapshot FLASH sequence (standard), a T1- and T2-weighted spin-echo (SE) sequence, and a T1-weighted breath-hold FLASH sequence. Whereas snapshot FLASH images in both pulse sequences were free from physiological motion artifacts, SE and FLASH images showed respiratory artifacts in some patients. Quantitative analysis of IFA snapshot FLASH images at low hepatic and low lesion signal revealed both superior lesion-liver signal-difference-to-noise ratio (SD/N) and superior contrast compared with standard snapshot FLASH without additional artifacts. Unless motion artifacts were evident, SE and FLASH images showed a higher anatomic resolution but lower SD/N and lower contrast than IFA snapshot images. Because of its superior SD/N and contrast, IFA snapshot FLASH will likely widen the application of fast MR imaging techniques.     

MR imaging of cardiac thrombi

This retrospective study of 10 magnetic resonance (MR) examinations in patients with cardiac thrombi (eight in left ventricle and two in right atrium) was performed to assess the ability of MR for demonstrating cardiac thrombi and describe the appearance of cardiac thrombi using the spin echo technique. Cardiac thrombi usually had higher signal intensity than the normal myocardium on MR imaging, especially on the second echo (TE of 56 or 60 ms) image. Differentiation between cardiac thrombus and intracardiac signal resulting from slowly flowing blood was possible based on different signal intensity changes using various techniques. In conclusion, MI imaging constitutes another noninvasive modality for the detection of cardiac thrombus. Further work is needed to determine its accuracy compared with that of two-dimensional echocardiography.     

Fast breath-hold T2-weighted MR imaging reduces interobserver variability in the diagnosis of adenomyosis

OBJECTIVE: We compared two rapid MR imaging T2-weighted pulse sequences with high-resolution turbo spin-echo for the diagnosis of adenomyosis, and we evaluated interobserver variability. SUBJECTS AND METHODS: Fifty-six consecutive patients referred for hysterectomy prospectively underwent MR imaging. Two fast pulse sequences using a breath-hold technique-true fast imaging with steady-state free precession (FISP) and turbo inversion recovery-and turbo spin-echo T2-weighted images of the pelvis were obtained in each patient. The images were analyzed in a blinded manner and independently by three reviewers with different levels of experience for the accuracy of adenomyosis diagnosis, image quality, anatomic visualization, and image artifacts. The accuracy for the diagnosis of adenomyosis on turbo spin-echo T2-weighted imaging combined with one or two fast pulse sequences was evaluated for each reviewer. RESULTS: Twenty-four patients (42.9%) had a histologic diagnosis of adenomyosis. The accuracy for the diagnosis of adenomyosis for reviewers 1, 2, and 3 using turbo spin-echo T2-weighted, true FISP, and turbo inversion recovery sequences was 83.9%, 67.8%, 75%; 83.9%, 67.8, 78.5%; and 87.5%, 73.2%, and 75%, respectively. A difference in the accuracy rate was found among the observers for the three sequences (p < 0.001). Whatever the pulse sequence, the accuracy rate was higher for the reviewer with more experience in gynecologic imaging. The combination of turbo spin-echo T2-weighted imaging with at least one rapid sequence increased the accuracy of observers with little experience in gynecology. With turbo inversion recovery sequences, the image quality score was low for the three reviewers compared with turbo spin-echo T2-weighted and true FISP sequences. The combination of turbo spin-echo T2-weighted and true FISP sequences gave the highest image quality scores. CONCLUSION: Breath-hold T2-weighted sequences optimize the accuracy of MR imaging for the diagnosis of adenomyosis and reduce interobserver variability.     

Combined arterial and venous whole-body MR angiography with cardiac MR imaging in patients with thromboembolic disease—initial experience

The objective was to assess the feasibility of a combined arterial and venous whole-body three-dimensional magnetic resonance (MR) angiography, together with a cardiac MR examination, in patients with arterial thromboembolism. Ten patients with arterial thromboembolism underwent a contrast-enhanced whole-body MR examination of the arterial and venous vessels, followed by a cardiac MR examination on a separate occasion within 24 h. All examinations were performed on a 1.5-T MR scanner. For both arterial and venous MR angiography only one injection of contrast agent was necessary. The cardiac imaging protocol included dark-blood-prepared half-Fourier acquisition single-shot turbo-spin-echo sequences, fast steady-state free precession cine sequences, T2-weighted turbo-spin-echo sequences and inversion recovery gradient-echo fast low-angle-shot sequences after injection of contrast agent. MR imaging revealed additional clinically unknown arterial thromboembolisms in four patients. The thoracic aorta was depicted as embolic source in four patients, while deep vein thrombosis (DVT) was found in one patient as the underlying disease. Unsuspected infarction of parenchymal organs was detected by MRI in two patients. An unknown additional DVT was found in one patient. Four patients were considered to have arterial emboli of cardiac origin. In conclusion, acquisition of arterial and venous MR angiograms of the entire vascular system combined with cardiac MR imaging is a most comprehensive and valuable strategy in patients with arterial thromboembolism.     

Cine MR angiography of the heart with segmented true fast imaging with steady-state precession

In five healthy subjects and 18 patients, cine magnetic resonance (MR) imaging of the heart was performed with a true fast imaging with steady-state precession (FISP) sequence. Results were compared both quantitatively and qualitatively with those at cine fast low-angle shot (FLASH) MR imaging. The blood-myocardial contrast-to-noise ratio (CNR) was 2.0 times higher and the normalized (for measurement time and pixel size) blood-myocardial CNR was 4.0 times higher for true FISP compared with FLASH MR imaging. Qualitative scores for image quality were significantly higher with true FISP MR imaging. Segmented cine true FISP MR imaging generated high-contrast MR images of the heart in healthy subjects and in patients with heart disease and produced image quality superior to that with cine FLASH MR imaging.