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Hajime Sakuma

Publications and source records attributed to Hajime Sakuma.

At least 19 recordsLinked to original sources
PubMed2006

Detection of coronary artery stenosis with whole-heart coronary magnetic resonance angiography.

OBJECTIVES: We sought to determine the diagnostic performance of whole-heart coronary magnetic resonance (MR) angiography for detecting significant coronary artery disease. BACKGROUND: The accuracy of whole-heart coronary MR angiography has not been determined in a large number of patients. METHODS: Three-dimensional coronary MR angiograms covering the entire heart were obtained during free breathing in 131 patients. Images were acquired during a patient-specific time window in the cardiac cycle with minimal motion of the coronary artery. Significant coronary artery disease was defined on X-ray coronary angiography as a diameter reduction of > or =50% in coronary arteries with a reference diameter of > or =2 mm. RESULTS: The acquisition of MR angiography was completed in 113 (86%) of 131 patients, with an imaging time averaged at 12.9 +/- 4.3 min. On a patient-based analysis, the sensitivity, specificity, positive and negative predictive value, and accuracy of MR angiography were 82% (95% confidence interval [CI] 69% to 91%), 90% (95% CI 79% to 96%), 88% (95% CI 74% to 95%), 86% (95% CI 75% to 93%), and 87% (95% CI 79% to 92%), respectively. These values in the individual segments were 78% (95% CI 68% to 85%), 96% (95% CI 95% to 97%), 69% (95% CI 60% to 77%), 98% (95% CI 96% to 98%), and 94% (95% CI 96% to 96%). CONCLUSIONS: Whole-heart coronary MR angiography allows for noninvasive detection of significant narrowing in coronary arterial segments with a diameter of > or =2 mm with moderate sensitivity and high specificity.

Aged↗
PubMed2006

Apparent diffusion coefficient in malignant lymphoma and carcinoma involving cavernous sinus evaluated by line scan diffusion-weighted imaging.

PURPOSE: To evaluate the apparent diffusion coefficient (ADC) of malignant lymphomas and carcinomas involving cavernous sinus by line scan diffusion-weighted imaging (LSDWI) and to determine the usefulness of this method for differentiating between the two tumors. MATERIALS AND METHODS: Four patients with malignant lymphomas and six patients with carcinomas were prospectively studied. LSDWI images were obtained with two different b values of 5 seconds/mm(2) and 1000 seconds/mm(2) in the coronal plane. The ADC values of the two types of tumors were calculated and compared. RESULTS: LSDWI provided diagnostic images with minimum susceptibility artifacts and enabled measurement of the ADC. The ADC value (mean +/- SD) was 0.51 +/- 0.06 x 10(-3) mm(2)/second in malignant lymphomas and 0.99 +/- 0.08 x 10(-3) mm(2)/second in carcinomas. A significant difference in ADC values was found between the two (P < 0.01). CONCLUSION: Malignant lymphomas showed significantly lower ADC value than carcinomas. ADC provides additional useful information about differentiation between these tumors.

Adult↗
PubMed2006

Comparison of MRI and positron emission tomography for measuring myocardial perfusion reserve in healthy humans.

Myocardial perfusion reserve (MPR, defined as the ratio of the maximum myocardial blood flow (MBF) to the baseline) is an indicator of coronary artery disease and myocardial microvascular abnormalities. First-pass contrast-enhanced magnetic resonance imaging (CE-MRI) using gadolinium (Gd)-DTPA as a contrast agent (CA) has been used to assess MPR. Tracer kinetic models based on compartmental analysis of the CA uptake have been developed to provide quantitative measures of MBF by MRI. To study the accuracy of Gd-DTPA first-pass MRI and kinetic modeling for quantitative analysis of myocardial perfusion and MPR during dipyridamole infusion, we conducted a comparison with positron emission tomography (PET) in 18 healthy males (age = 40 +/- 14 years). Five planes were acquired at every second heartbeat with a 1.5T scanner using a saturation recovery turboFLASH sequence. A perfusion-related parameter, the unidirectional influx constant (Ki), was computed in three coronary artery territories. There was a significant correlation for both dipyridamole-induced flow (0.70, P = 0.001) and MPR (0.48, P = 0.04) between MRI and PET. However, we noticed that MRI provided lower MPR values compared to PET (2.5 +/- 1.0 vs. 4.3 +/- 1.8). We conclude that MRI supplemented with tracer kinetic modeling can be used to quantify myocardial perfusion.

Adult↗
PubMed2005

Contrast-enhanced MR imaging for evaluation of coronary artery disease before elective repair of aortic aneurysm.

PURPOSE: To prospectively evaluate the accuracy of first-pass contrast material-enhanced magnetic resonance (MR) imaging during stress and delayed contrast-enhanced MR imaging in the detection of significant coronary artery disease in patients before elective repair of aortic aneurysm. MATERIALS AND METHODS: The study was approved by the institutional ethics committee, and informed consent was obtained from all patients. MR imaging was performed in 49 patients (42 men and seven women; mean age, 72.2 years; age range, 58-85 years) before the elective repair of atherosclerotic aortic aneurysms. Thirty-two patients had an abdominal aneurysm, 12 had a thoracic aneurysm, and five had a thoracoabdominal aneurysm. First-pass contrast-enhanced MR images were obtained with short-axis sections encompassing the entire left ventricular myocardium in the resting state and during pharmacologic stress. Inversion-recovery-prepared delayed contrast-enhanced MR images were obtained with breath holding to evaluate for the presence of infarction. All patients underwent coronary angiography within 2 weeks of MR imaging, and these findings were used as the standard of reference. The diagnostic results of first-pass contrast-enhanced MR imaging, delayed contrast-enhanced MR imaging, and a combination of both MR imaging methods in the detection of significant coronary artery disease were expressed as sensitivity, specificity, and accuracy. RESULTS: Coronary angiography depicted a clinically significant stenosis (>70% luminal diameter narrowing) in the coronary artery in 34 of the 49 patients (69%). First-pass contrast-enhanced MR imaging depicted stress-induced hypoenhancement in 27 of those 34 patients (79%). Delayed myocardial enhancement was observed in 17 of the 34 patients (50%). The overall sensitivity of rest-stress first-pass contrast-enhanced MR imaging and delayed contrast-enhanced MR imaging combined in the prediction of at least one coronary artery with significant stenosis was 88% (30 of 34 patients). The specificity and accuracy of MR imaging were 87% (13 of 15 patients) and 88% (43 of 49 patients), respectively. CONCLUSION: Contrast-enhanced MR imaging had an accuracy of 88% in the detection of significant coronary artery disease in patients with aortic aneurysm.

Aged↗
PubMed2005

Assessment of coronary arteries with total study time of less than 30 minutes by using whole-heart coronary MR angiography.

This study had institutional review board approval, and all patients gave informed consent. The purpose of this study was to prospectively evaluate the use of whole-heart three-dimensional (3D) coronary magnetic resonance (MR) angiography in patients suspected of having coronary artery disease. Whole-heart coronary MR angiography was performed in 39 patients (30 men and nine women; mean age, 63.9 years +/- 15.6 [standard deviation]) by using a steady-state free precession sequence with free breathing. Twenty patients (16 men and four women; mean age, 64.9 years +/- 11.7) also underwent conventional coronary angiography. MR angiography was successfully completed in 34 of 39 patients (87%); the average imaging time was 13.8 minutes +/- 3.8. Sensitivity and specificity of MR angiography for detecting significant stenosis were 82% (14 of 17 arteries) and 91% (39 of 43 arteries), respectively. Whole-heart coronary MR angiography with a navigator-gated steady-state sequence can enable reliable 3D visualization of the coronary arteries in patients suspected of having coronary artery disease.

Coronary Angiography↗
PubMed2005

Late gadolinium-enhanced magnetic resonance imaging in acute and chronic myocardial infarction. Improved prediction of regional myocardial contraction in the chronic state by measuring thickness of nonenhanced myocardium.

OBJECTIVES: We sought to determine serial changes of enhanced and nonenhanced tissue on late gadolinium-enhanced cardiac magnetic resonance (CMR) imaging in patients with a myocardial infarction (MI) and to assess whether thickness of nonenhanced myocardium can improve the detection of preserved contractile function in the chronic state. BACKGROUND: Previous studies demonstrated that enhancement on late gadolinium-enhanced CMR images indicates myocardial necrosis, and nonenhancement shows the presence of viable myocardium. METHODS: The CMR studies were performed within one week (scan 1) and more than five months (scan 2) after the onset of MI in 18 patients. The area and mean thickness of enhanced tissue and nonenhanced myocardium were measured by using a 30-segment model. Systolic wall thickening on cine CMR at scan 2 was assessed for evaluating regional contractile function. RESULTS: The amount of enhanced tissue significantly decreased from scan 1 to 2 (22.1 +/- 14.0 ml vs. 15.0 +/- 9.3 ml, p < 0.001). The averaged thickness of nonenhanced myocardium in the infarct segments significantly increased from scan 1 to 2 (5.2 +/- 3.0 mm vs. 6.6 +/- 3.2 mm, p < 0.001). Receiver operating characteristic analysis demonstrated that the measurement of thickness of nonenhanced myocardium, compared with measurement of percent transmural enhancement, had better diagnostic accuracy for predicting improved systolic wall thickening form scan 1 to 2 in dysfunctional segments (Az 0.650 vs. 0.594, p < 0.05). CONCLUSIONS: The amounts of enhanced tissue and nonenhanced myocardium significantly altered from the acute to chronic state in MI patients. The diagnostic performance of CMR imaging for detection of preserved contractile function can be significantly improved by measuring thickness of nonenhanced myocardium in MI patients.

Aged↗
PubMed2005

Feasibility of integrating high-spatial-resolution 3D breath-hold coronary MR angiography with myocardial perfusion and viability examinations.

The study was institutional review board approved and Health Insurance Portability and Accountability Act compliant. All subjects provided informed consent. Three-dimensional breath-hold coronary magnetic resonance (MR) angiography with use of steady-state free precession was performed in 12 patients up to 20 minutes after 0.2 mmol gadolinium-based contrast material per kilogram of body weight was administered. Within 24 heartbeats, a spatial resolution of up to 1.0 x 1.2 x 2.0 mm was achieved. Sixty-five (82%) of the 79 visualized coronary artery segments had a grade of 3 or 4 on a four-point scale of depiction in which grade 4 indicated excellent depiction. Twenty-seven percent (n = 21) of the 79 segments were assigned a grade of 4; 56% (n = 44), a grade of 3; 16% (n = 13), a grade of 2; and 1% (n = 1), a grade of 1. Coronary MR angiography performed as part of a first-pass myocardial perfusion and viability assessment MR imaging examination is feasible and does not involve additional imaging time.

Adult↗
PubMed2005

Diagnostic accuracy of stress first-pass contrast-enhanced myocardial perfusion MRI compared with stress myocardial perfusion scintigraphy.

OBJECTIVE: The purpose of this study was to determine the diagnostic accuracy of stress perfusion MRI acquired with saturation-recovery prepared turbo fast low-angle shot (turbo FLASH) compared with stress myocardial perfusion scintigraphy. Recent studies show that first-pass contrast-enhanced myocardial perfusion MRI can provide noninvasive detection of low-limiting stenosis in the coronary artery. MATERIALS AND METHODS: First-pass contrast-enhanced MR images were acquired at rest and during stress in 40 patients with suspected coronary artery disease. All patients underwent thallium-201 SPECT without attenuation correction and coronary angiography. Two reviewers independently assigned one of five confidence grades without knowing the results of coronary angiography for receiver operating characteristic (ROC) analysis. Luminal stenosis >70% on coronary angiography was used as a reference standard. RESULTS: On coronary angiography, 70% or greater diameter stenosis of the coronary artery was observed in 21 (52.5%) of 40 patients. The areas under the ROC curve for detection of significant stenosis in the individual coronary artery were 0.86 (observer 1) and 0.84 (observer 2) for MRI. These values were 0.79 (observer 1, p = not significant) and 0.72 (observer 2, p = not significant) for 201Tl SPECT. CONCLUSION: The diagnostic accuracy of stress perfusion MRI acquired with saturation-recovery-prepared turbo FLASH was comparable with that of stress 201Tl SPECT. Stress first-pass contrast-enhanced MRI is a noninvasive technique that can be used as an alternative to stress myocardial perfusion scintigraphy.

Contrast Media↗
PubMed2005

Usefulness of the apparent diffusion coefficient in line scan diffusion-weighted imaging for distinguishing between squamous cell carcinomas and malignant lymphomas of the head and neck.

BACKGROUND AND PURPOSE: Squamous cell carcinoma (SCC) and lymphoma are common malignant tumors of the head and neck. The purpose of this study was to determine whether the apparent diffusion coefficient (ADC) in line scan diffusion-weighted imaging (LSDWI) is useful for distinguishing between SCC and lymphoma of the head and neck. METHODS: LSDWI was prospectively performed in 39 patients with SCC and in 14 patients with lymphoma. Images were obtained with a diffusion-weighted factor (b factor) of 5 and 1000 s/mm(2), and ADC maps were generated. ADC values were measured for the two types of tumor. RESULTS: Mean ADC values were 0.96 +/- 0.11 x 10(-3) mm(2)/s for SCC and 0.65 +/- 0.09 x 10(-3) mm(2)/s for lymphoma; the difference was significant (P < .001). All but one of the patients with lymphoma had ADC values lower than the lowest ADC (0.76 x 10(-3) mm(2)/s) in patients with SCC. When an ADC of 0.76 x 10(-3) mm(2)/s was used to distinguish between SCC and lymphoma, accuracy was 98% (52 of 53 lesions). CONCLUSION: ADC values appear to be useful for distinguishing between SCC and lymphoma in the head and neck.

Adolescent↗
PubMed2004

Thallium-201 SPECT and low-dose dobutamine stress cine MRI for predicting functional recovery of regional myocardial contraction in patients with myocardial infarction.

OBJECTIVES: The purpose of this study was to compare the diagnostic performances of Tl-201 single photon emission computed tomography (SPECT) and dobutamine stress cine magnetic resonance imaging (MRI) for predicting functional recovery of regional myocardial contraction in patients after myocardial infarction. METHODS: Twenty patients underwent Tl-201 SPECT and MRI 3-4 weeks after onset of myocardial infarction. Cine MR images were acquired in the resting state and during dobutamine stress. Tl-201 uptake and systolic wall thickening (SWT) on cine MRI were analyzed on short-axis images by using a 14-segment model. Follow-up cine MR images were obtained 187.1+/-33.5 days after onset. RESULTS: The averaged Tl-201 uptake in 54 segments with impaired SWT was 47%+/-20%, being significantly lower than that in 226 segments with preserved SWT (75%+/-18%; p<0.0001). The sensitivity, specificity, and accuracy of dobutamine MRI and Tl-201 SPECT for predicting preserved SWT after 6 months were 89% vs. 80%, not significant (NS); 89% vs. 72%, p<0.01; and 89% vs. 79%, NS, respectively. In the anterior wall and apex, the sensitivity and specificity of SPECT were not significantly different from those of MRI. In the inferior wall and posterolateral wall, however, the specificity of SPECT was substantially lower than that of MRI (53% vs. 88%, p<0.001), resulting in significantly lower accuracy (75% vs. 90%, p<0.01). CONCLUSIONS: Both SPECT and dobutamine MRI showed excellent sensitivity for predicting myocardial viability in all left ventricular segments. Decreased specificity of SPECT in the inferior and posterolateral segments resulted in lower overall specificity in comparison with dobutamine MRI.

Adult↗
PubMed2004

Contrast-enhanced high-resolution MRI of invasive breast cancer: correlation with histopathologic subtypes.

OBJECTIVE: We sought to determine whether contrast-enhanced MRI could aid in the identification of the histopathologic subtypes of invasive ductal carcinoma. MATERIALS AND METHODS: We evaluated the contrast-enhanced MR images obtained in 62 women with invasive ductal carcinoma of no special type. The presence or absence of three distinct MRI findings-linear enhancement, a serrated border, and delayed rim enhancement-was evaluated. Classification and regression tree analyses were performed to construct the most efficient algorithm for predicting histopathologic subtype on the basis of dynamic MRI features. RESULTS: Histopathologic subtypes of the invasive ductal carcinomas were scirrhous carcinoma in 22 patients, solid tubular carcinoma in 14, and papillotubular carcinoma in 26. A lesion with a serrated border was observed in 28 (45.2%) of the 62 patients. Delayed rim enhancement was seen in 23 (37.1%) and linear enhancement in 20 (32.3%). Scirrhous carcinomas were closely associated with a serrated border (20/22 or 90.9%, p < 0.0001). Delayed rim enhancement was frequently observed in solid tubular carcinomas (12/14 or 85.7%, p < 0.0001) but was not typically seen in scirrhous carcinomas (1/22 or 4.5%, p < 0.0001). Linear enhancement showed relatively high prevalence in papillotubular carcinomas (13/26 or 50%) and low prevalence in solid tubular carcinomas (1/22 or 7%, p < 0.02). Histopathologic subtypes of invasive breast carcinoma of no special type could be correctly identified in 47 (75.8%) of 62 lesions using the diagnostic algorithm generated by the classification and regression tree analyses. CONCLUSION: MRI features showed a close relationship with histopathologic subtypes of invasive ductal carcinoma of no special type. Contrast-enhanced MRI can be a noninvasive diagnostic tool for histopathologic subtypes of invasive breast cancer.

Adult↗
PubMed2003

Noninfarcted myocardium: correlation between dynamic first-pass contrast-enhanced myocardial MR imaging and quantitative coronary angiography.

PURPOSE: To determine the accuracy of first-pass contrast material-enhanced stress myocardial magnetic resonance (MR) imaging for depiction of myocardial ischemia in patients without myocardial infarction. MATERIALS AND METHODS: First-pass contrast-enhanced MR images of the entire left ventricle were acquired in 104 patients at rest and during dipyridamole-induced stress by using an interleaved notched saturation technique. Coronary angiography was performed in all patients, and stress perfusion single photon emission computed tomography (SPECT) was performed in 69 patients. Receiver operating characteristic curve analysis was performed to compare the diagnostic accuracies of first-pass contrast-enhanced stress MR imaging and stress SPECT, with coronary angiography as the reference standard. RESULTS: The overall sensitivity of MR imaging for depicting at least one coronary artery with significant stenosis was 90% (69 of 77 patients). The sensitivities of MR imaging for depiction of single-, double-, and triple-vessel stenoses were 85% (33 of 39 patients), 96% (22 of 23 patients), and 100% (15 of 15 patients), respectively. The specificity of MR imaging for identification of patients with significant coronary artery stenoses was 85% (23 of 27 patients). The areas under the receiver operating characteristic curve for detection of significant stenosis in individual coronary arteries were 0.888 (observer 1) and 0.911 (observer 2) for MR imaging and 0.707 (observer 1, P <.001) and 0.750 (observer 2, P <.001) for SPECT. CONCLUSION: In patients without myocardial infarction, stress enhancement at dynamic MR imaging correlates more closely with quantitative coronary angiography results than does stress enhancement at SPECT.

Adult↗
PubMed2003

Abnormal hyperintensity within the subarachnoid space evaluated by fluid-attenuated inversion-recovery MR imaging: a spectrum of central nervous system diseases.

A variety of central nervous system (CNS) diseases are associated with abnormal hyperintensity within the subarachnoid space (SAS) by fluid-attenuated inversion-recovery (FLAIR) MR imaging. Careful attention to the SAS can provide additional useful information that may not be available with conventional MR sequences. The purpose of this article is to provide a pictorial essay about CNS diseases and FLAIR images with abnormal hyperintensity within the SAS. We present several CNS diseases including subarachnoid hemorrhage, meningitis, leptomeningeal metastases, acute infarction, and severe arterial occlusive diseases such as moya-moya disease. We also review miscellaneous diseases or normal conditions that may exhibit cerebrospinal fluid hyperintensity on FLAIR images. Although the detection of abnormal hyperintensity suggests the underlying CNS diseases and narrows differential diagnoses, FLAIR imaging sometimes presents artifactual hyperintensity within the SAS that can cause the misinterpretation of normal SAS as pathologic conditions; therefore, radiologists should be familiar with such artifactual conditions as well as pathologic conditions shown as hyperintensity by FLAIR images. This knowledge is helpful in establishing the correct diagnosis.

Adult↗
PubMed2003

Evaluation of left ventricular volumes and ejection fraction using fast steady-state cine MR imaging: comparison with left ventricular angiography.

Previous studies demonstrated that magnetic resonance (MR) imaging consistently underestimated angiographic measurements of left ventricular (LV) volumes. The purpose of this study was to determine whether MR imaging with steady-state free precession acquisition (SSFP) can provide improved accuracy and reproducibility in measuring cardiac function in comparison with fast spoiled gradient echo cine MR imaging (SPGR). Twenty patients with cardiovascular diseases who underwent breath-hold cine MR imaging within one week of LV angiography were studied. Two sets of breath-hold cine MR images were obtained, one with SSFP and another with SPGR. The LV volumes determined by two breath-hold cine MR sequences were compared with the results by LV angiography. SPGR cine MR imaging consistently underestimated angiographic LV volumes. The mean difference of LV end-diastolic volume was -22.5 +/- 14.8 ml (p < 0.001) for short-axis planes and -27.7 +/- 21.5 ml (p < 0.001) for long-axis planes. In contrast, LV volumes measured by the SSFP imaging showed a good agreement with the results by angiography. The mean difference of LV end-diastolic volume was -2.5 +/- 14.3 ml (p = N.S.) for short-axis planes and -10.9 +/- 15.1 ml (p < 0.01) for long-axis planes. Standard error of the estimation in measuring LV end-diastolic volume with the SSFP imaging was 3.9% for short-axis images and 4.9% for long-axis images. These values were 7.2% and 8.7% with the SPGR imaging. In conclusion, the SSFP acquisition can provide accurate and noninvasive assessments of LV volumes and ejection fraction within a reduced imaging time.

Adult↗
PubMed2003

Prediction of regional functional recovery after acute myocardial infarction with low dose dobutamine stress cine MR imaging and contrast enhanced MR imaging.

PURPOSE: Previous studies demonstrated that low-dose dobutamine stress cine magnetic resonance imaging (MRI) and delayed contrast-enhanced MRI can provide assessments of myocardial viability. The purpose of this study was to evaluate the comparative diagnostic values of dobutamine cine MRI and delayed contrast-enhanced MRI for predicting functional recovery of myocardial contraction in patients with acute reperfused myocardial infarction. METHODS: Twenty-three patients with myocardial infarction after percutaneous coronary interventions were studied. All patients underwent steady-state cine MRI covering the entire left ventricle at rest and during low-dose dobutamine stress (10 micrograms/kg/min). Delayed contrast-enhanced MR images were acquired to determine transmural extent of hyperenhancement. Second cine MR images in the resting state were obtained 3 to 11 months after revascularization. RESULTS: On the first cine MR images in the resting state, 278 (20%) of 1380 segments demonstrated abnormal, regional contraction (systolic wall thickening < 40%). Of the 175 segments showing functional recovery on the following cine MRI, 156 (89%) segments were recognized as reversible by dobutamine cine MRI and 146 (83%) segments by delayed contrast-enhanced MRI. The sensitivity, specificity, and accuracy of dobutamine stress cine MRI was 89%, 80%, and 86%, respectively. These values of contrast-enhanced MRI were 83%, 72%, and 79%, respectively. The area under the receiver operating curve (ROC) was 0.87 by dobutamine cine MRI and 0.78 by delayed contrast-enhanced MRI (p < 0.05). CONCLUSIONS: The current results using quantitative segmental analysis indicated that low-dose dobutamine stress cine MRI can predict recovery of myocardial contractility with significantly higher diagnostic performance in comparison with contrast-enhanced MRI in patients with myocardial infarction who underwent revascularization.

Adult↗
PubMed2003

Increased myocardial uptake of iodine-123 metaiodobenzylguanidine on delayed images, compared with early images, in patients with multiple system atrophy.

We present 2 interesting cases of multiple system atrophy in which increased myocardial iodine-123 metaiodobenzylguanidine uptake was observed on delayed images (3 hours after injection) compared with early images (15 minutes after injection). These findings have not been previously described. The duration of symptoms was less than 1 year in both these patients. The mechanism responsible for these findings is not clearly understood, but could be related to the pathophysiological changes in the early stage of multiple systemic atrophy.

3-Iodobenzylguanidine↗
PubMed2003

Acute myocardial infarction: myocardial viability assessment in patients early thereafter comparison of contrast-enhanced MR imaging with resting (201)Tl SPECT. Single photon emission computed tomography.

PURPOSE: To compare contrast material-enhanced magnetic resonance (MR) imaging with resting thallium 201 ((201)Tl) single photon emission computed tomography (SPECT) for predicting myocardial viability in patients early after acute myocardial infarction. MATERIALS AND METHODS: Inversion-recovery contrast-enhanced MR images and resting (201)Tl SPECT images were obtained in 22 patients after acute myocardial infarction. The (201)Tl SPECT images were obtained 4.3 days +/- 0.2 (standard error) after the onset of myocardial infarction. Contrast-enhanced MR imaging was performed 7.9 days +/- 1.6 after (201)Tl SPECT. Transmural extent of hyperenhancement on contrast-enhanced MR images and regional (201)Tl activity were quantitatively analyzed with a 12-segment model. Regional wall thickening on follow-up cine MR images obtained 67 days +/- 17 after contrast-enhanced MR imaging was used as an index for myocardial viability. Statistical analyses were performed with the chi(2) and two-tailed Student t tests. RESULTS: Both contrast-enhanced MR and resting (201)Tl SPECT images showed significant correlations with regional wall thickening on follow-up cine MR images. The sensitivity, specificity, and accuracy of contrast-enhanced MR imaging in the prediction of viable myocardium were significantly higher than those of resting (201)Tl SPECT (98.0% vs 90.3%, P <.01; 75.0% vs 54.4%, P <.05; and 92.0% vs 81.1%, P <.001, respectively). CONCLUSION: Delayed contrast-enhanced MR imaging can help predict myocardial viability as seen on follow-up cine MR images after acute myocardial infarction, with significantly improved sensitivity, specificity, and accuracy in comparison with those of resting (201)Tl SPECT.

Female↗