Purpose: To compare the diagnostic value of mono-exponential, bi-exponential, and stretched exponential diffusion-weighted imaging (DWI) for differentiating benign and malignant hepatic lesions.
Motivation: The diagnosis of heart failure is based on clinical symptoms because noninvasive methods for early diagnosis are still insufficient. Goal(s): Considering reactive oxygen species contribute to heart failure, we hypothesized much earlier signs of heart failure could be captured by focusing on redox metabolism. Approach: We used a doxorubicin-induced mouse model of heart failure and analyzed at an early stage. To visualize redox metabolism, we used in vivo dynamic nuclear polarization MRI. We also evaluated the cardiomyocytes microscopically. Results: The intracardiac redox metabolism was enhanced in 30 min after doxorubicin administration compared to the control group although no significant cardiomyocyte changes were observed. Impact: In the early stages of heart failure, redox metabolism is altered even before the morphological changes are observed microscopically. These data provide a technique for detecting heart failure earlier and less invasively than conventional testing methods.
Background: 99mTc-sestamibi myocardial perfusion imaging (MIBI) washout is associated with myocardial mitochondrial damage in patients with a successful percutaneous coronary intervention (PCI) following acute myocardial infarction (AMI) and may predict the functional improvement of the left ventricle in follow-ups. Objectives: This study aimed to investigate the clinical efficacy of 99mTc-MIBI washout in patients with AMI by measuring the mean defect area based on 99mTc-MIBI myocardial perfusion-single photon emission computed tomography (MP-SPECT) rest imaging in early and delayed phases and comparing it with the defect area based on 99mTc-MIBI MP-SPECT adenosine stress imaging based on a two-day rest/stress protocol. Patients and Methods: This study was conducted on 29 consecutive patients with AMI (23 males and 6 females; mean age, 71 ± 8.4 years), who underwent MP-SPECT using a standard two-day rest/stress protocol. The rest 99mTc-MIBI MP-SPECT images were acquired in the early phase at one hour after the injection of 99mTc-MIBI and in the delayed phase at three hours after the early phase. The total perfusion deficit (TPD) score for SPECT was measured to compare the defect area between the rest-early phase, rest-delayed phase, and post-stress imaging conditions. Results: Based on the results, the post-stress TPD score was significantly lower than the rest-delayed phase score (TPD: 22.2% ± 14.3% vs. 27.8% ± 14.0%; P < 0.001). Also, the rest-early phase score was significantly lower than the rest-delayed phase score (TPD: 21.5% ± 14.9% vs. 27.8% ± 14.0%; P < 0.001). However, no significant difference was observed between the post-stress score and the rest-early phase score. Conclusion: The combination of rest-early phase, delayed phase, and post-stress 99mTc-MIBI imaging using a two-day protocol after AMI reperfusion was a clinically useful method, which could identify residual ischemia and predict the left ventricular function improvement in the chronic phase of disease while reducing the exposure dose.
