Artificial Intelligence-Enabled Quantitative Coronary Plaque and Hemodynamic Analysis for Predicting Acute Coronary Syndrome.

BACKGROUND: A lesion-level risk prediction for acute coronary syndrome (ACS) needs better characterization. OBJECTIVES: This study sought to investigate the additive value of artificial intelligence-enabled quantitative coronary plaque and hemodynamic analysis (AI-QCPHA). METHODS: Among ACS patients who underwent coronary computed tomography angiography (CTA) from 1 month to 3 years before the ACS event, culprit and nonculprit lesions on coronary CTA were adjudicated based on invasive coronary angiography. The primary endpoint was the predictability of the risk models for ACS culprit lesions. The reference model included the Coronary Artery Disease Reporting and Data System, a standardized classification for stenosis severity, and high-risk plaque, defined as lesions with ≥2 adverse plaque characteristics. The new prediction model was the reference model plus AI-QCPHA features, selected by hierarchical clustering and information gain in the derivation cohort. The model performance was assessed in the validation cohort. RESULTS: Among 351 patients (age: 65.9 ± 11.7 years) with 2,088 nonculprit and 363 culprit lesions, the median interval from coronary CTA to ACS event was 375 days (Q1-Q3: 95-645 days), and 223 patients (63.5%) presented with myocardial infarction. In the derivation cohort (n = 243), the best AI-QCPHA features were fractional flow reserve across the lesion, plaque burden, total plaque volume, low-attenuation plaque volume, and averaged percent total myocardial blood flow. The addition of AI-QCPHA features showed higher predictability than the reference model in the validation cohort (n = 108) (AUC: 0.84 vs 0.78; P < 0.001). The additive value of AI-QCPHA features was consistent across different timepoints from coronary CTA. CONCLUSIONS: AI-enabled plaque and hemodynamic quantification enhanced the predictability for ACS culprit lesions over the conventional coronary CTA analysis. (Exploring the Mechanism of Plaque Rupture in Acute Coronary Syndrome Using Coronary Computed Tomography Angiography and Computational Fluid Dynamics II [EMERALD-II]; NCT03591328).

Coronary computed tomography angiography for clinical practice.

Coronary artery disease (CAD) is a common condition caused by the accumulation of atherosclerotic plaques. It can be classified into stable CAD or acute coronary syndrome. Coronary computed tomography angiography (CCTA) has a high negative predictive value and is used as the first examination for diagnosing stable CAD, particularly in patients at intermediate-to-high risk. CCTA is also adopted for diagnosing acute coronary syndrome, particularly in patients at low-to-intermediate risk. Myocardial ischemia does not always co-exist with coronary artery stenosis, and the positive predictive value of CCTA for myocardial ischemia is limited. However, CCTA has overcome this limitation with recent technological advancements such as CT perfusion and CT-fractional flow reserve. In addition, CCTA can be used to assess coronary artery plaques. Thus, the indications for CCTA have expanded, leading to an increased demand for radiologists. The CAD reporting and data system (CAD-RADS) 2.0 was recently proposed for standardizing CCTA reporting. This RADS evaluates and categorizes patients based on coronary artery stenosis and the overall amount of coronary artery plaque and links this to patient management. In this review, we aimed to review the major trials and guidelines for CCTA to understand its clinical role. Furthermore, we aimed to introduce the CAD-RADS 2.0 including the assessment of coronary artery stenosis, plaque, and other key findings, and highlight the steps for CCTA reporting. Finally, we aimed to present recent research trends including the perivascular fat attenuation index, artificial intelligence, and the advancements in CT technology.

Feasibility of four-dimensional similarity filter for radiation dose reduction in dynamic myocardial computed tomography perfusion imaging.

Rationale and objectives: We aimed to evaluate the impact of four-dimensional noise reduction filtering using a four-dimensional similarity filter (4D-SF) on radiation dose reduction in dynamic myocardial computed tomography perfusion (CTP). Materials and methods: Forty-three patients who underwent dynamic myocardial CTP using 320-row computed tomography (CT) were included in the study. The original images were reconstructed using iterative reconstruction (IR). Three different CTP datasets with simulated noise, corresponding to 25%, 50%, and 75% reduction of the original dose (300 mA), were reconstructed using a combination of IR and 4D-SF. The signal-to-noise ratio (SNR) and contrast-to-noise ratio (CNR) were assessed, and CT-derived myocardial blood flow (CT-MBF) was quantified. The results were compared between the original and simulated images with radiation dose reduction. Results: The median SNR (first quartile-third quartile) at the original, 25%-, 50%-, and 75%-dose reduced-simulated images with 4D-SF was 8.3 (6.5-10.2), 16.5 (11.9-21.7), 15.6 (11.0-20.1), and 12.8 (8.8-18.1) and that of CNR was 4.4 (3.2-5.8), 6.7 (4.6-10.3), 6.6 (4.3-10.1), and 5.5 (3.5-9.1), respectively. All the dose-reduced-simulated CTPs with 4D-SF had significantly higher image quality scores in SNR and CNR than the original ones (25%-, 50%-, and 75%-dose reduced vs. original images, p < 0.05, in each). The CT-MBF in 75%-dose reduced-simulated CTP was significantly lower than 25%-, 50%- dose-reduced-simulated, and original CTPs (vs. 75%-dose reduced-simulated images, p < 0.05, in each). Conclusion: 4D-SF has the potential to reduce the radiation dose associated with dynamic myocardial CTP imaging by half, without impairing the robustness of MBF quantification.

Role of amide proton transfer imaging in maximizing tumor resection in malignant glioma: a possibility to take the place of 11C-methionine positron emission tomography.

BACKGROUND: Amide proton transfer (APT) imaging has been proposed as a technique to assess tumor metabolism. However, the relationship between APT imaging and other quantitative modalities including positron emission tomography (PET) has not been investigated in detail. This study aimed to evaluate the clinical usefulness of APT imaging in determining the metabolic status of malignant glioma and to compare findings with those from 11C-methionine (Met)-PET. METHODS: This research analyzed APT imaging data from 20 consecutive patients with malignant glioma treated between January 2022 and July 2023. Patients underwent tumor resection and correlations between tumor activity and intensity of APT signal were investigated. We also compared 11C-Met-PET and APT imaging for the same regions of the perifocal tumor invasion area. RESULTS: Clear, diagnostic APT images were obtained from all 20 cases. Mean APT intensity (APTmean) was significantly higher in the glioblastoma (GBM), IDH wild type group (27.2 ± 12.8%) than in other gliomas (6.0 ± 4.7%; p < 0.001). The cut-off APTmean to optimally distinguish between GBM and other malignant gliomas was 12.8%, offering 100% sensitivity and 83.3% specificity. These values for APTmean broadly matched the tumor-to-contralateral normal brain tissue ratio from 11C-Met-PET analysis (r = 0.66). The APT signal was also observed in the gadolinium non-contrast region on T1-weighted imaging, appearing to reflect the surrounding tumor-infiltrated area. CONCLUSIONS: APT imaging can be used to evaluate the area of tumor invasion, similar to 11C-Met-PET. APT imaging revealed low invasiveness in patients and was useful in preoperative planning for tumor resection, facilitating maximum tumor resection including the tumor invasive area.

Impact of digital positron emission tomography/computed tomography on the delineation of clinical target volume in advanced lung cancer.

The present study investigated the differences between digital [18F]-Fluorodeoxyglucose (FDG) positron emission tomography [PET]/computed tomography [CT] (dPET/CT) and conventional PET/CT (cPET/CT) in delineating the clinical target volume (CTV) in patients with advanced lung cancer in the involved field radiation therapy (IFRT) era. Patients with advanced lung cancer were scanned using two dual-imaging protocols (dPET/CT and cPET/CT). Two virtual delineations contoured with reference to dPET/CT and cPET/CT images were created for each patient by five radiation oncologists. Changes in the delineation of target volumes in each patient were examined. A total of 10 patients [male/female, 9/1; median age, 65 years (range, 58-80 years)] were enrolled between April 2020 and September 2020. Significant changes in the delineation of CTVs were uncommon between dPET/CT and cPET/CT. A notable increase in CTVn was observed in 10% of the patients (1/10; P<0.05; Smirnov-Grubbs analysis). In this patient, a node that was not assessed as lymph node metastasis when cPET/CT was used was assessed as lymph node metastasis when dPET/CT was used and was included in the CTVn by all five radiation oncologists. In patients with advanced lung cancer, notable changes in CTV delineations are uncommon, regardless of whether dPET/CT or cPET/CT is used. However, in some cases, CTVn delineation with reference to dPET/CT may improve the treatment outcomes of IFRT for advanced lung cancer.

Impact of timing of radium­223 administration on the survival of patients with bone metastatic castration­resistant prostate cancer.

The present study aimed to evaluate the optimal timing of radium-223 chloride (Ra-223) administration among patients with bone metastasis from castration-resistant prostate cancer (BmCRPC). Patients, who were diagnosed with BmCRPC and treated with Ra-223 therapy between October, 2016 and January, 2022, were reviewed. The survival time was calculated from the initiation of Ra-223 administration. The time from the diagnosis of BmCRPC to the initiation of Ra-223 administration was identified as a potential prognostic factor. A total of 51 patients were examined in the present study. Ra-223 was administered as the first- and second-line therapy (earlier Ra-223 administration) in 32 patients and as the third- to fifth-line therapy (later Ra-223 administration) in 19 patients. In the multivariate analysis, which considered the potential prognosis, the difference in survival times between patients who received early and late Ra-223 administration was not significant [hazard ratio (HR), 2.67; 95% confidence interval (CI), 0.79-9.07; P=0.11]. By contrast, an incomplete Ra-223 administration (HR, 128.03; 95% CI, 10.59-1548.42; P<0.01) and higher levels of prostate-specific antigen prior to Ra-223 administration (HR, 7.86; 95% CI, 2.7-27.24; P<0.01) were independent factors, significantly associated with a poorer prognosis. The timing of Ra-223 administration did not significantly affect the survival of patients from the initiation of treatment. Further studies are thus required to determine the optimal timing for Ra-223 administration.

The dynamics of deglutition during head rotation using dynamic 320-row area detector computed tomography.

Objective: We aimed to elucidate the dynamics of deglutition during head rotation by acquiring 320-row area detector computed tomography (320-ADCT) images and analyzing deglutition during head rotation. Methods: This study included 11 patients experiencing globus pharyngeus. A 320-ADCT was used to acquire images in two types of viscosity (thin and thick), with the head rotated to the left. We measured the movement time of deglutition-related organs (soft palate, epiglottis, upper esophageal sphincter [UES], and true vocal cords) and pharyngeal volume (bolus ratio at the start of UES opening [Bolus ratio], pharyngeal volume contraction ratio [PVCR], and pharyngeal volume before swallowing [PVBS]). A two-way analysis of variance was performed for statistical analysis, and all items were compared for significant differences in terms of head rotation and viscosity. EZR was used for all statistical analyses (p-value <.05). Results: Head rotation significantly accelerated the onset of epiglottis inversion and UES opening compared with no head rotation. The duration of epiglottis inversion with the thin viscosity fluid was significantly longer. The bolus ratio increased significantly with thick viscosity. There was no significant difference in viscosity and head rotation in terms of PVCR. PVBS increased significantly with head rotation. Conclusion: The significantly earlier start of epiglottis inversion and UES opening due to head rotation could be caused by: (1) swallowing center; (2) pharyngeal volume; and (3) pharyngeal contraction force. Thus, we plan to further analyze swallowing with head rotation by combining swallowing CT with manometry and examine its relationship with pharyngeal contraction force. Level of Evidence: 3b.

Effect of preparation method for radioactive iodine therapy on serum electrolytes.

PURPOSE: Thyroid hormone withdrawal (THW) in preparation for radioactive iodine therapy (RIT) may lead to hyponatremia and hyperkalemia because hypothyroidism reduces the glomerular filtration rate. Using recombinant human thyrotropin (rhTSH) may avoid these changes; however, these two preparation methods have not been compared in the literature. The purpose of this study was to reveal whether THW and rhTSH as preparation methods for RIT affect serum electrolytes differently. We also evaluated clinical factors influencing the onset of hyponatremia and hyperkalemia during RIT. MATERIALS AND METHODS: From April 2005 to December 2020, we analyzed 278 patients with thyroid cancer who received RIT. The patients were classified into two groups based on the preparation method, and renal function and serum electrolytes were compared between the groups. We also evaluated clinical factors that may affect overt hyponatremia (serum sodium level < 134 mmol/L) and hyperkalemia (serum potassium level ≥ 5.0 mmol/L). RESULTS: Serum sodium and chloride levels in the THW group were significantly lower than those in the rhTSH group (p < 0.001 and p = 0.002, respectively). In contrast, the serum potassium level in the THW group was significantly higher than that in the rhTSH group (p = 0.008). As for clinical factors that may influence hyponatremia, age and estimated glomerular filtration rate (eGFR) were significantly associated with serum sodium level in the univariate analysis (p = 0.033 and p = 0.006, respectively). In the multivariate analysis, only age was significantly associated with serum sodium level (p = 0.030). Regarding hyperkalemia, distant metastases, the preparation method and eGFR were significantly associated with the serum potassium level in the univariate analysis (p = 0.005, p = 0.005 and p = 0.001, respectively). In the multivariate analysis, only eGFR was significantly associated with hyperkalemia (p = 0.019). CONCLUSION: THW and rhTSH affect serum sodium and potassium levels differently. Renal function may be risk factors for hyperkalemia, whereas older age may be a risk factor for hyponatremia.

Feasibility of Bone Mineral Density and Bone Microarchitecture Assessment Using Deep Learning With a Convolutional Neural Network.

OBJECTIVES: We evaluated the feasibility of using deep learning with a convolutional neural network for predicting bone mineral density (BMD) and bone microarchitecture from conventional computed tomography (CT) images acquired by multivendor scanners. METHODS: We enrolled 402 patients who underwent noncontrast CT examinations, including L1-L4 vertebrae, and dual-energy x-ray absorptiometry (DXA) examination. Among these, 280 patients (3360 sagittal vertebral images), 70 patients (280 sagittal vertebral images), and 52 patients (208 sagittal vertebral images) were assigned to the training data set for deep learning model development, the validation, and the test data set, respectively. Bone mineral density and the trabecular bone score (TBS), an index of bone microarchitecture, were assessed by DXA. BMDDL and TBSDL were predicted by deep learning with a convolutional neural network (ResNet50). Pearson correlation tests assessed the correlation between BMDDL and BMD, and TBSDL and TBS. The diagnostic performance of BMDDL for osteopenia/osteoporosis and that of TBSDL for bone microarchitecture impairment were evaluated using receiver operating characteristic curve analysis. RESULTS: BMDDL and BMD correlated strongly (r = 0.81, P < 0.01), whereas TBSDL and TBS correlated moderately (r = 0.54, P < 0.01). The sensitivity and specificity of BMDDL for identifying osteopenia or osteoporosis were 93% and 90%, and 100% and 94%, respectively. The sensitivity and specificity of TBSDL for identifying patients with bone microarchitecture impairment were 73% for all values. CONCLUSIONS: The BMDDL and TBSDL derived from conventional CT images could identify patients who should undergo DXA, which could be a gatekeeper tool for detecting latent osteoporosis/osteopenia or bone microarchitecture impairment.

Factors affecting local control of bone metastases from radioresistant tumors treated with palliative external beam radiotherapy.

BACKGROUND: This study aimed to evaluate the factors that affect the local control (LC) of bone metastases from radioresistant carcinomas (renal cell carcinoma, hepatocellular carcinoma [HCC], and colorectal carcinoma [CRC]) treated with palliative external-beam radiotherapy (EBRT). METHODS AND MATERIALS: Between January 2010 and December 2020, 211 bone metastases in 134 patients were treated with EBRT in two hospitals (a cancer center and university hospital). Based on follow-up CT, these cases were reviewed retrospectively to evaluate LC at the EBRT site. RESULTS: The median EBRT dose (BED10) was 39.0 Gy (range, 14.4-66.3 Gy). The median follow-up time of the imaging studies was 6 months (range, 1-107 months). The 0.5-year overall survival and LC rates of the EBRT sites were 73% and 73%, respectively. Multivariate analysis revealed that the primary sites (HCC/CRC), low EBRT dose (BED10) (≤ 39.0 Gy), and non-administration of post-EBRT bone modifying agents (BMAs) and/or antineoplastic agents (ATs) were statistically significant factors that negatively affected the LC of EBRT sites. In the absence of BMAs or ATs, the EBRT dose (BED10) escalation from 39.0 Gy improved the LC of EBRT sites. Based on ATs administration, the LC of EBRT sites was significantly affected by tyrosine kinase inhibitors and/or immune checkpoint inhibitors. CONCLUSIONS: Dose escalation improves LC in bone metastases from radioresistant carcinomas. Higher EBRT doses are needed to treat patients for whom few effective systemic therapies remain available.

Prognostic assessment of patients who receive radiotherapy for bone metastases from breast cancer.

For prognostic assessment in women who receive radiotherapy (RT) for bone metastases (BMs) from breast cancer (BC), prognostic factors specific for BMs from BC were investigated in the present study. The prognostic assessment was performed by retrospectively reviewing 143 women who received first-time RT for BMs from BC between January 2007 and June 2018. The median follow-up time and median overall survival (OS) time from the first-time RT for BMs were 22 and 18 months, respectively. In the multivariate analysis, nuclear grade 3 (NG 3) [hazard ratio, 2.18; 95% confidence interval (CI), 1.34-3.53], brain metastases (hazard ratio, 1.96; 95% CI, 1.01-3.81), liver metastases (hazard ratio, 1.75; 95% CI, 1.17-2.63), performance status (PS) (hazard ratio, 1.63; 95% CI, 1.10-2.41) and previous systemic therapy (hazard ratio, 1.58; 95% CI, 1.03-2.42) were significant factors for OS, whereas age, hormone-receptor/human epidermal growth factor receptor 2 status, number of BMs and synchronous lung metastases were not significant factors. When points according to risk levels [unfavorable points (UFPs)] were assigned to each risk factor (1.5 points for NG 3 and brain metastases; and 1 point for PS ≥2, previous systemic therapy and liver metastases), the median OS times of patients with a total number of UFPs ≤1 (n=45), 1.5-3 (n=55) and ≥3.5 (n=43) were 36, 17 and 6 months, respectively. Overall, in patients who received first-time RT for BMs from BC, NG 3, brain/liver metastases, poor PS and previous systemic therapy were unfavorable prognostic factors. Comprehensive prognostic assessment using these factors seemed to be useful for the prediction of prognoses in patients with BMs from BC.

Comparisons of Hepatobiliary Phase Imaging Using Combinations of Parallel Imaging and Variable Degrees of Compressed Sensing With Use of Parallel Imaging Alone.

OBJECTIVE: This study aimed to compare the image quality in the hepatobiliary phase images of gadoxetic acid-enhanced liver magnetic resonance imaging using parallel imaging (PI) and compressed sensing (CS) reconstruction, using variable CS factors with the standard method using the PI technique. METHODS: In this study, 64 patients who underwent gadoxetic acid-enhanced liver magnetic resonance imaging at 3.0 T were enrolled. Hepatobiliary phase images were acquired 6 times using liver acquisition with volume acceleration (LAVA) and CS reconstruction with 5 CS factors 1.4, 1.6, 1.8, 2.0, and 2.5 (LAVA-CS 1.4, 1.6, 1.8, 2.0, and 2.5) and standard LAVA (LAVA-noCS). For objective analysis, the signal intensity ratios (SIRs) of the liver-to-spleen (SIR liver/spleen ), liver-to-portal vein (SIR liver/portal vein ), and liver-to-fat (SIR liver/fat ) were estimated. For subjective analysis, 2 radiologists independently evaluated the quality of all the images. RESULTS: The objective analysis demonstrated no significant difference in all evaluation parameters of all the images. Subjective analysis revealed that the scores of all evaluation items were higher for LAVA-noCS images than for LAVA-CS images, and only LAVA-CS 1.4 did not significantly differ from LAVA-noCS in all evaluation items ( P = 1.00 in 2 readers). CONCLUSIONS: A CS factor of 1.4 in the hepatobiliary phase image with combined PI and CS can reduce the scan time without degrading the image quality compared with the standard method.

Factors Affecting Survival and Local Control in Patients with Bone Metastases Treated with Radiotherapy.

The aim of this study was to evaluate the expected prognosis and factors affecting local control (LC) of the bone metastatic sites treated with palliative external beam radiotherapy (RT). Between December 2010 and April 2019, 420 cases (male/female = 240/180; median age [range]: 66 [12-90] years) with predominantly osteolytic bone metastases received RT and were evaluated. LC was evaluated by follow-up computed tomography (CT) image. Median RT doses (BED10) were 39.0 Gy (range, 14.4-71.7 Gy). The 0.5-year overall survival and LC of RT sites were 71% and 84%, respectively. Local recurrence on CT images was observed in 19% (n = 80) of the RT sites, and the median recurrence time was 3.5 months (range, 1-106 months). In univariate analysis, abnormal laboratory data before RT (platelet count, serum albumin, total bilirubin, lactate dehydrogenase, or serum calcium level), high-risk primary tumor sites (colorectal, esophageal, hepatobiliary/pancreatic, renal/ureter, and non-epithelial cancers), no antineoplastic agents (ATs) administration after RT, and no bone modifying agents (BMAs) administration after RT were significantly unfavorable factors for both survival and LC of RT sites. Sex (male), performance status (≥3), and RT dose (BED10) (<39.0 Gy) were significantly unfavorable factors for only survival, and age (≥70 years) and bone cortex destruction were significantly unfavorable factors for only LC of RT sites. In multivariate analysis, only abnormal laboratory data before RT influenced both unfavorable survival and LC of RT sites. Performance status (≥3), no ATs administration after RT, RT dose (BED10) (<39.0 Gy), and sex (male) were significantly unfavorable factors for survival, and primary tumor sites and BMAs administration after RT were significantly unfavorable factors for LC of RT sites. In conclusion, laboratory data before RT was important factor both prognosis and LC of bone metastases treated with palliative RT. At least in patients with abnormal laboratory data before RT, palliative RT seemed to be focused on the only pain relief.

Left atrial strain assessment using cardiac computed tomography in patients with hypertrophic cardiomyopathy.

PURPOSE: To evaluate left atrial (LA) function in patients with hypertrophic cardiomyopathy (HCM) by LA strain assessment using cardiac computed tomography (CT-derived LA strain). MATERIALS AND METHODS: This was a retrospective study of 34 patients with HCM and 31 non-HCM patients who underwent cardiac computed tomography (CT) using retrospective electrocardiogram-gated mode. CT images were reconstructed every 5% (0-95%) of the RR intervals. CT-derived LA strain (reservoir [LASr], conduit [LASc], and booster pump strain [LASp]) were semi-automatically analyzed using a dedicated workstation. We also measured the left atrial volume index (LAVI) and left ventricular longitudinal strain (LVLS) for the left atrial and ventricular functional parameters to assess the relationship with CT-derived LA strain. RESULTS: CT-derived LA strain significantly correlated with LAVI: r = - 0.69, p < 0.001 for LASr; r = - 0.70, p < 0.001 for LASp; and r = - 0.35, p = 0.004 for LASc. CT-derived LA strain also significantly correlated with LVLS: r = - 0.62, p < 0.001 for LASr; r = - 0.67, p < 0.001 for LASc; and r = - 0.42, p = 0.013 for LASp. CT-derived LA strain in patients with HCM was significantly lower than that in non-HCM patients: LASr (20.8 ± 7.6 vs. 31.7 ± 6.1%, p < 0.001); LASc (7.9 ± 3.4 vs. 14.2 ± 5.3%, p < 0.001); and LASp (12.8 ± 5.7 vs. 17.6 ± 4.3%, p < 0.001). Additionally, CT-derived LA strain showed high reproducibility; inter-observer correlation coefficients were 0.94, 0.90, and 0.89 for LASr, LASc, and LASp, respectively. CONCLUSION: CT-derived LA strain is feasible for quantitative assessment of left atrial function in patients with HCM.

Prognostic value of human epidermal growth factor receptor 2 status and systemic therapy in breast cancer with brain metastases treated with radiotherapy.

PURPOSE: To evaluate the prognostic value of human epidermal growth factor receptor 2 (HER2) status and how to use HER2-targeted therapy in breast cancer (BC) with brain metastases (BM) treated with radiotherapy. METHODS: We retrospectively reviewed the data of 103 BC patients with parenchymal BM treated with radiotherapy. We collected data on the hormone receptor (HR), HER-2 amplification status, and systemic therapy after treatment for BM. The primary outcome was overall survival (OS), which was calculated from the diagnosis of BM to death. RESULTS: The median follow-up time from the diagnosis of the first BM was 9.1 months (range, .7-88 months). The 2-year OS of the HR-positive and HER2-positive (HR+HER2+) BC (31.3 mo) was significantly better than those of the HR-HER2+ (9,5 mo, p=.002), HR+HER2- (9.9mo, p=.003), and triple-negative BC (3.9 mo, p<.001) ( . Of the 36 HER2-positive patients, 31 patients treated with HER2-targeted therapy after radiotherapy for BM had a significantly better 2-year OS than those who did not receive HER2-targeted therapy (43% vs. 0%; p < .001). Among the 31 patients treated with HER2-targeted therapy, the 2-year OS for those treated with multiple anti-HER2 agents during the entire course of treatment was significantly higher than that for patients treated with a single agent (60% vs. 24%; p = .006). CONCLUSIONS: HR+HER2+ BC patients with BM treated with radiotherapy show a better prognosis than other subtypes. For HER2-positive patients with good prognosis, it may be important to continue HER2-targeted therapy appropriately after radiotherapy for BM.

Free-breathing cardiovascular cine magnetic resonance imaging using compressed-sensing and retrospective motion correction: accurate assessment of biventricular volume at 3T.

PURPOSE: We applied a combination of compressed-sensing (CS) and retrospective motion correction to free-breathing cine magnetic resonance (MR) (FBCS cine MoCo). We validated FBCS cine MoCo by comparing it with breath-hold (BH) conventional cine MR. MATERIALS AND METHODS: Thirty-five volunteers underwent both FBCS cine MoCo and BH conventional cine MR imaging. Twelve consecutive short-axis cine images were obtained. We compared the examination time, image quality and biventricular volumetric assessments between the two cine MR. RESULTS: FBCS cine MoCo required a significantly shorter examination time than BH conventional cine (135 s [110-143 s] vs. 198 s [186-349 s], p < 0.001). The image quality scores were not significantly different between the two techniques (End-diastole: FBCS cine MoCo; 4.7 ± 0.5 vs. BH conventional cine; 4.6 ± 0.6; p = 0.77, End-systole: FBCS cine MoCo; 4.5 ± 0.5 vs. BH conventional cine; 4.5 ± 0.6; p = 0.52). No significant differences were observed in all biventricular volumetric assessments between the two techniques. The mean differences with 95% confidence interval (CI), based on Bland-Altman analysis, were - 0.3 mL (- 8.2 - 7.5 mL) for LVEDV, 0.2 mL (- 5.6 - 5.9 mL) for LVESV, - 0.5 mL (- 6.3 - 5.2 mL) for LVSV, - 0.3% (- 3.5 - 3.0%) for LVEF, - 0.1 g (- 8.5 - 8.3 g) for LVED mass, 1.4 mL (- 15.5 - 18.3 mL) for RVEDV, 2.1 mL (- 11.2 - 15.3 mL) for RVESV, - 0.6 mL (- 9.7 - 8.4 mL) for RVSV, - 1.0% (- 6.5 - 4.6%) for RVEF. CONCLUSION: FBCS cine MoCo can potentially replace multiple BH conventional cine MR and improve the clinical utility of cine MR.

Clinical features and prognosis of isolated cardiac sarcoidosis diagnosed using new guidelines with dedicated FDG PET/CT.

BACKGROUND: Diagnostic guidelines for isolated cardiac sarcoidosis (iCS) were first proposed in 2016, but there are few reports on the imaging and prognosis of iCS. This study aimed to evaluate the use of 18F-fluorodeoxyglucose positron emission tomography/computed tomography (FDG PET/CT) imaging in predicting iCS prognosis. METHODS AND RESULTS: We retrospectively reviewed the clinical and imaging data of 306 consecutive patients with suspected CS who underwent FDG PET/CT with a dedicated preparation protocol and included 82 patients (55 with systemic sarcoidosis including cardiac involvement [sCS], 27 with iCS) in the study. We compared the FDG PET/CT findings between the two groups. We examined the relationship between the CS type and the rate of adverse cardiac events. The iCS group had a significantly lower target-to-background ratio than the sCS group (P = 0.0010). The event-free survival rate was significantly lower in the iCS group than the sCS group (log-rank test, P < 0.0001). iCS was identified as an independent prognostic factor for adverse events (hazard ratio 3.82, P = 0.0059). CONCLUSION: iCS was an independent prognostic factor for adverse cardiac events in patients with CS. The clinical diagnosis of iCS based on FDG PET/CT and new guidelines may be important.

Neural network-based fully automated cardiac resting phase detection algorithm compared with manual detection in patients.

Background: A cardiac resting phase is used when performing free-breathing cardiac magnetic resonance examinations. Purpose: The purpose of this study was to test a cardiac resting phase detection system based on neural networks in clinical practice. Material and Methods: Four chamber-view cine images were obtained from 32 patients and analyzed. The rest duration, start point, and end point were compared between that determined by the experts and general operators, and a similar comparison was done between that determined by the experts and neural networks: the normalized root-mean-square error (RMSE) was also calculated. Results: Unlike manual detection, the neural network was able to determine the resting phase almost simultaneously as the image was obtained. The rest duration and start point were not significantly different between the neural network and expert (p = .30, .90, respectively), whereas the end point was significantly different between the two groups (p < .05). The start point was not significantly different between the general operator and expert (p = .09), whereas the rest duration and end point were significantly different between the two groups (p < .05). The normalized RMSEs of the rest duration, start point, and end point of the neural network were 0.88, 0.64, and 0.33 ms, respectively, which were lower than those of the general operator (normalized RMSE values were 0.98, 0.68, and 0.51 ms, respectively). Conclusions: The neural network can determine the resting phase instantly with better accuracy than the manual detection of general operators.

Local control after palliative external beam radiotherapy for bone metastases in patients with favorable prognosis.

Advancement in systemic therapy has increased the importance of local control (LC) of bone metastatic sites treated with radiotherapy in intermediate-term survivors (surviving ≥1 year). To establish individualized radiotherapy for bone metastases, factors affecting LC of bone metastases treated with traditional fractionated moderate dose palliative radiotherapy (FMRT) in intermediate-term survivors were evaluated. Between January 2010 and December 2019, 317 lesions in 240 patients treated with FMRT for bone metastases surviving for at least 1 year and followed-up with CT for at least 6 months were reviewed retrospectively. The median survival and radiographic follow-up times were 24 months (range, 12-123 months) and 20 months (range, 1-119 months), respectively. The median FMRT dose [biologically effective dose (BED)10] was 39.0 Gy (range, 28.0-71.7 Gy). Multivariate analysis revealed that age (≥70 years), non-vertebral bone metastasis, bone metastasis from moderate and unfavorable primary tumor sites (esophageal, colorectal, hepatobiliary/pancreatic, kidney/ureter and sarcoma/melanoma cancers), and no administration of post-FMRT bone-modifying agents (BMAs) were unfavorable factors for LC of bone metastasis. The 2-year LC rates for FMRT doses (BED10) ≤39.0 Gy and >39.0 Gy were 90 and 87%, respectively. The 2-year LC rates of patients administered and not administered post-FMRT antineoplastic agents (ATs) were 91 and 78%, respectively. The sites of bone metastasis and primary tumors, and post-FMRT BMAs were factors associated with LC of bone metastasis in long-term survivors. However, a FMRT dose (BED10) ≥39.0 Gy and post-FMRT ATs were not significant factors.