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1.
J Formos Med Assoc ; 116(5): 366-372, 2017 May.
Article in English | MEDLINE | ID: mdl-27497908

ABSTRACT

BACKGROUND/PURPOSE: Vascular calcification can predict cardiovascular (CV) morbidity and mortality in patients with end-stage renal disease. We evaluated the prevalence, association factors, and outcomes of chest X-ray-detected aortic arch calcification (AoAC) in patients undergoing peritoneal dialysis (PD). METHODS: We included 190 patients undergoing PD (mean age, 52.6 ± 14.3 years) for whom chest radiographs were available. AoAC revealed by chest X-ray was graded from 0 to 3 according to an AoAC score (AoACS). Multiple regression analyses were used to determine the factors associated with AoACS. After adjusting for age, sex, PD duration, diabetes mellitus, mean blood pressure, and history of CV disease, the association between AoAC grading and mortality were assessed using the Kaplan-Meier curve and Cox proportional hazard model. RESULTS: Age (p < 0.001), PD duration (p = 0.004), history of CV disease (p < 0.001), and renal Kt/V (p = 0.031) were associated with AoACS. After a mean follow-up of 55.1 ± 32.1 months, patients with Grade 2 (p = 0.011) or Grade 3 (p < 0.001) AoAC had higher all-cause mortality than patients with Grade 0 AoAC. In addition, patients with Grades 2 and 3 AoAC had higher CV-related mortality than those with Grades 0 and 1 AoAC (p = 0.013). Grade 2 [hazard ratio (HR) = 2.736; 95% confidence interval (CI), 1.038-7.211; p = 0.042] and Grade 3 AoAC (HR = 3.289; 95% CI, 1.156-9.359; p = 0.026) remained associated with all-cause mortality after adjustment. Similarly, Grades 2 and 3 AoAC (HR = 36.05; 95% CI, 3.494-372; p = 0.026) significantly correlated with CV mortality after adjustment. CONCLUSION: In patients undergoing PD, CXR-detected severe AoAC was an independent risk factor for all-cause and CV mortalities.


Subject(s)
Aortic Diseases/mortality , Kidney Failure, Chronic/complications , Peritoneal Dialysis/mortality , Vascular Calcification/mortality , Adult , Aged , Aorta, Thoracic/diagnostic imaging , Aorta, Thoracic/pathology , Aortic Diseases/diagnostic imaging , Aortic Diseases/etiology , Cardiovascular Diseases/complications , Female , Humans , Kaplan-Meier Estimate , Kidney Failure, Chronic/therapy , Male , Middle Aged , Proportional Hazards Models , Radiography , Regression Analysis , Risk Factors , Time Factors , Vascular Calcification/diagnostic imaging , Vascular Calcification/etiology
2.
J Endovasc Ther ; 23(6): 867-877, 2016 12.
Article in English | MEDLINE | ID: mdl-27629440

ABSTRACT

PURPOSE: To assess the angiographic and clinical outcomes in patients with erectile dysfunction and isolated penile artery stenoses treated by balloon angioplasty. METHODS: In this prospective study, 22 patients (mean age 61.0±7.6 years, range 50-79) with erectile dysfunction and 34 isolated penile artery stenoses (mean 74.9%±9.1%) were enrolled and underwent balloon angioplasty. The mean International Index for Erectile Function-5 (IIEF-5) score at baseline was 10.3±4.5. The mean lesion length was 11.1±9.0 mm (mean reference vessel diameter 1.7±0.4 mm). The primary endpoint was in-segment restenosis ≥50% by pelvic computed tomography angiography (CTA) at 8 months. The 1-year sustained clinical success (IIEF-5 score ≥22 or a ≥4-point change in the IIEF-5 score and no later decline by ≥4) was the secondary outcome measure. RESULTS: Procedural success was achieved in 31 (91%) of 34 stenotic lesions; there was 1 flow-limiting dissection and 2 arteries with >30% residual stenosis. At 8 months, 14 of 34 lesions in 13 of 22 patients had CTA-documented binary restenosis. At 1 year, sustained clinical success was achieved in 11 of 22 patients. Of the 9 patients not developing binary restenosis, 8 achieved sustained clinical success. CONCLUSION: Our findings establish the safety and efficacy of penile artery angioplasty for patients with erectile dysfunction and isolated penile artery stenoses. They also highlight the unmet need for a more enduring treatment strategy for penile artery stenotic disease.


Subject(s)
Angioplasty, Balloon , Arteries/diagnostic imaging , Computed Tomography Angiography , Impotence, Vasculogenic/etiology , Multidetector Computed Tomography , Penile Erection , Penis/blood supply , Peripheral Arterial Disease/therapy , Aged , Angioplasty, Balloon/adverse effects , Arteries/physiopathology , Constriction, Pathologic , Humans , Impotence, Vasculogenic/diagnosis , Impotence, Vasculogenic/physiopathology , Male , Middle Aged , Peripheral Arterial Disease/complications , Peripheral Arterial Disease/diagnostic imaging , Peripheral Arterial Disease/physiopathology , Predictive Value of Tests , Prospective Studies , Recovery of Function , Recurrence , Time Factors , Treatment Outcome , Vascular Patency
3.
Acta Cardiol Sin ; 32(2): 145-55, 2016 Mar.
Article in English | MEDLINE | ID: mdl-27122945

ABSTRACT

PURPOSE: Several studies have suggested that a combined approach of stress myocardial perfusion imaging (MPI) and coronary computed tomography angiography (CCTA) can provide diagnostic results with excellent accuracy. We aimed to explore whether the addition of CCTA to stress MPI provides incremental diagnostic value in intermediate-to-high cardiovascular risk patients. METHODS: A total of 106 consecutive patients (93 male, 65 ± 10.4 years) underwent coronary artery calcium scoring (CACS), CCTA and (201)Thallium stress MPI before coronary angiography was reviewed. Thirty-seven patients (34.9%) had a history of proven coronary artery disease (CAD) or revascularization procedures, and four had documented non-significant CAD (3.8%). The remaining patients consisted of 17 (16.0%) classified as intermediate, and 48 (45.3%) as the high-risk groups. RESULTS: Obstructive CAD was diagnosed by invasive coronary angiography in 88 patients with 161 vessels. The sensitivity and specificity in a patient-based analysis for obstructive CAD were 99% and 17% for CCTA, 80% and 50% for MPI and 91% and 67% for the combined method, respectively. The per-vessel diagnostic sensitivity and specificity were 95% and 54% for CCTA, 59% and 75% for MPI and 84% and 76% for the combined method. There were significant differences (p < 0.05) when comparing the combined method with MPI or CCTA by areas under the curve in a patient- or vessel-based analysis. However, CACS of 400 or more could not further stratify the patients with obstructive CAD. CONCLUSIONS: CCTA, not CACS, provided additional diagnostic values to stress MPI in patients with intermediate-to-high cardiovascular risk. KEY WORDS: Coronary artery disease (CAD) • Coronary computed tomography angiography (CCTA) • Myocardial perfusion imaging (MPI) • Single-photon emission computed tomography (SPECT).

4.
Acta Cardiol Sin ; 32(2): 167-73, 2016 Mar.
Article in English | MEDLINE | ID: mdl-27122947

ABSTRACT

UNLABELLED: Coronary computed tomographic angiography (CCTA) has been widely available since 2004. After that, the diagnostic accuracy of CCTA has been extensively validated with invasive coronary angiography for detection of coronary arterial stenosis. In this paper, we reviewed the updated evidence of the role of CCTA in both scenarios including acute chest pain and screening in asymptomatic adults. Several large-scale studies have been conducted to evaluate the diagnostic value of CCTA in the context of acute chest pain patients. CCTA could play a role in delivering more efficient care. For risk stratification of asymptomatic patients using CCTA, latest studies have revealed incremental benefits. Future studies evaluating the totality of plaque characteristics may be useful for determining the role of noncalcified plaque for risk stratification in asymptomatic individuals. KEY WORDS: Acute chest pain • Computed tomography • Coronary artery disease • Health screening • Stable angina.

5.
Anal Chem ; 87(15): 7575-82, 2015 Aug 04.
Article in English | MEDLINE | ID: mdl-26146882

ABSTRACT

On the basis of an infrared femtosecond Cr:forsterite laser, we developed a semiquantitative method to analyze the microscopic distribution of bilirubins. Using 1230 nm femtosecond pulses, we selectively excited the two-photon red fluorescence of bilirubin dimers around 660 nm. Autofluorescences from other endogenous fluorophores were greatly suppressed. Using this distinct fluorescence measure, we found that poorly differentiated hepatocellular carcinoma (HCC) tissues on average showed 3.7 times lower concentration of bilirubins than the corresponding nontumor parts. The corresponding fluorescence lifetime measurements indicated that HCC tissues exhibited a longer lifetime (500 ps) than that of nontumor parts (300 ps). Similarly, oral cancer cell lines had longer lifetimes (>330 ps) than those of nontumor ones (250 ps). We anticipate the developed methods of bilirubin molecular imaging to be useful in diagnosing cancers or studying the dynamics of bilirubin metabolisms in live cells.


Subject(s)
Bilirubin/analysis , Bilirubin/metabolism , Carcinoma, Hepatocellular/chemistry , Carcinoma, Hepatocellular/diagnosis , Cell Line, Tumor , Dimerization , Humans , Liver/chemistry , Liver/pathology , Liver Neoplasms/chemistry , Microscopy, Fluorescence, Multiphoton , Molecular Diagnostic Techniques , Mouth Neoplasms/diagnosis
6.
J Med Syst ; 38(6): 55, 2014 Jun.
Article in English | MEDLINE | ID: mdl-24809703

ABSTRACT

This work presents a new method for segmenting coronary arteries automatically in computed tomography angiography (CTA) data sets. The method automatically isolates heart and coronary arteries from surrounding structures and search for the probable location of coronary arteries by 3D region growing. Based on the dilation of the probable location, discrete wavelet transformation (DWT) and λ - mean operation complete accurate detection of coronary arties. Finally, the proposed method is tested on clinical CTA data-sets. The results on clinical datasets show that the proposed method is able to extract each branch of arteries when comparing to commercial software GE Healthcare and delineated ground truth.


Subject(s)
Coronary Angiography/methods , Tomography, X-Ray Computed/methods , Wavelet Analysis , Algorithms , Humans , Radiographic Image Enhancement/methods , Radiographic Image Interpretation, Computer-Assisted/methods
7.
Korean J Radiol ; 25(7): 603-612, 2024 Jul.
Article in English | MEDLINE | ID: mdl-38942454

ABSTRACT

Artificial intelligence (AI) is rapidly gaining recognition in the radiology domain as a greater number of radiologists are becoming AI-literate. However, the adoption and implementation of AI solutions in clinical settings have been slow, with points of contention. A group of AI users comprising mainly clinical radiologists across various Asian countries, including India, Japan, Malaysia, Singapore, Taiwan, Thailand, and Uzbekistan, formed the working group. This study aimed to draft position statements regarding the application and clinical deployment of AI in radiology. The primary aim is to raise awareness among the general public, promote professional interest and discussion, clarify ethical considerations when implementing AI technology, and engage the radiology profession in the ever-changing clinical practice. These position statements highlight pertinent issues that need to be addressed between care providers and care recipients. More importantly, this will help legalize the use of non-human instruments in clinical deployment without compromising ethical considerations, decision-making precision, and clinical professional standards. We base our study on four main principles of medical care-respect for patient autonomy, beneficence, non-maleficence, and justice.


Subject(s)
Artificial Intelligence , Radiology , Humans , Asia , Societies, Medical
8.
Insights Imaging ; 14(1): 23, 2023 Feb 03.
Article in English | MEDLINE | ID: mdl-36735153

ABSTRACT

OBJECTIVES: This population-based study aimed to collect, analyze, and summarize the long-term trends in medical imaging use in Taiwan. METHODS: A retrospective cohort population-based study of medical imaging usage for the individuals who received care under the National Health Insurance system from 2000 to 2017. CT and MRI utilization rates were determined overall as well as across certain variables including patient age, hospital type, health care type, hospital characteristics, and geographic area. RESULTS: Individuals registered in our health insurance system have received 21,766,745 CT scans and 7,520,088 MRI scans from 2000 to 2017. Annual growth rates for both imaging types were positive over that period, though growth rates have slowed in recent years. The growth rate for CT use was greatest (9-12%) between 2001 and 2004, dropped to 2% in 2005, then generally rose thereafter, reaching 3% in 2017. Similarly, MRI use growth peaked at 24% between 2001 and 2003, dropped to 4% in 2005, then increased in a fluctuating manner, reaching 2% in 2017. CONCLUSION: Over the past 2 decades, CT and MRI use in Taiwan has increased sharply, especially in the oldest age group (≥ 60 years old), but growth rates have slowed in recent years. Increases in imaging use have corresponded with improved clinical outcomes, including greater life expectancy and reduced mortality rates, though further assessment is required to demonstrate a direct link with imaging. Nevertheless, the better clinical outcomes are also predisposed by the comprehensive care covered by the NHI system.

9.
Radiat Oncol ; 18(1): 187, 2023 Nov 10.
Article in English | MEDLINE | ID: mdl-37950307

ABSTRACT

BACKGROUND: Few dosimetric comparisons have been published between linear accelerator (LA)-based systems and CyberKnife (CK)-based robotic radiosurgery systems for cardiac radio-ablation in ventricular tachycardia. This study aimed to compare the dosimetry of noninvasive cardiac radio-ablation deliverable on LA with that on CK. METHODS: Thirteen patients who underwent noninvasive cardiac radio-ablation by LA were included. The prescribed dose was 25 Gy in 1 fraction, and the average planning target volume was 49.8 ± 31.0 cm3 (range, 14.4-93.7 cm3). CK plans were generated for comparison. RESULTS: Both the CK and LA plans accomplished appropriate dose coverage and normal tissue sparing. Compared with the LA plans, the CK plans achieved significantly lower gradient indices (3.12 ± 0.71 vs. 3.48 ± 0.55, p = 0.031) and gradient measures (1.00 ± 0.29 cm vs. 1.17 ± 0.29 cm, p < 0.001). They had similar equivalent conformity indices (CK vs. LA: 0.84 ± 0.08 vs. 0.87 ± 0.07, p = 0.093) and maximum doses 2 cm from the planning target volume (PTV) in any direction (CK vs. LA: 50.8 ± 9.9% vs. 53.1 ± 5.3%, p = 0.423). The dosimetric advantages of CK were more prominent in patients with a PTV of ≤ 50 cm3 or a spherical PTV. In patients with a PTV of > 50 cm3 or a non-spherical PTV, the LA and CK plans were similar regarding dosimetric parameters. CK plans involved more beams (232.2 ± 110.8 beams vs. 10.0 ± 1.7 arcs) and longer treatment times (119.2 ± 43.3 min vs. 22.4 ± 1.6 min, p = 0.007). CONCLUSIONS: Both CK and LA are ideal modalities for noninvasive cardiac radio-ablation. Upfront treatment should be considered based on clinical intent.


Subject(s)
Radiosurgery , Radiotherapy, Intensity-Modulated , Robotic Surgical Procedures , Tachycardia, Ventricular , Humans , Radiotherapy Planning, Computer-Assisted , Particle Accelerators , Radiotherapy Dosage , Tachycardia, Ventricular/radiotherapy , Tachycardia, Ventricular/surgery
10.
Korean J Radiol ; 24(4): 349-361, 2023 04.
Article in English | MEDLINE | ID: mdl-36907594

ABSTRACT

OBJECTIVE: To quantitatively assess the pulmonary vasculature using non-contrast computed tomography (CT) in patients with chronic thromboembolic pulmonary hypertension (CTEPH) pre- and post-treatment and correlate CT-based parameters with right heart catheterization (RHC) hemodynamic and clinical parameters. MATERIALS AND METHODS: A total of 30 patients with CTEPH (mean age, 57.9 years; 53% female) who received multimodal treatment, including riociguat for ≥ 16 weeks with or without balloon pulmonary angioplasty and underwent both non-contrast CT for pulmonary vasculature analysis and RHC pre- and post-treatment were included. The radiographic analysis included subpleural perfusion parameters, including blood volume in small vessels with a cross-sectional area ≤ 5 mm² (BV5) and total blood vessel volume (TBV) in the lungs. The RHC parameters included mean pulmonary artery pressure (mPAP), pulmonary vascular resistance (PVR), and cardiac index (CI). Clinical parameters included the World Health Organization (WHO) functional class and 6-minute walking distance (6MWD). RESULTS: The number, area, and density of the subpleural small vessels increased after treatment by 35.7% (P < 0.001), 13.3% (P = 0.028), and 39.3% (P < 0.001), respectively. The blood volume shifted from larger to smaller vessels, as indicated by an 11.3% increase in the BV5/TBV ratio (P = 0.042). The BV5/TBV ratio was negatively correlated with PVR (r = -0.26; P = 0.035) and positively correlated with CI (r = 0.33; P = 0.009). The percent change across treatment in the BV5/TBV ratio correlated with the percent change in mPAP (r = -0.56; P = 0.001), PVR (r = -0.64; P < 0.001), and CI (r = 0.28; P = 0.049). Furthermore, the BV5/TBV ratio was inversely associated with the WHO functional classes I-IV (P = 0.004) and positively associated with 6MWD (P = 0.013). CONCLUSION: Non-contrast CT measures could quantitatively assess changes in the pulmonary vasculature in response to treatment and were correlated with hemodynamic and clinical parameters.


Subject(s)
Angioplasty, Balloon , Hypertension, Pulmonary , Pulmonary Embolism , Humans , Female , Middle Aged , Male , Hypertension, Pulmonary/diagnostic imaging , Hypertension, Pulmonary/therapy , Hypertension, Pulmonary/complications , Pulmonary Embolism/complications , Pulmonary Embolism/diagnostic imaging , Pulmonary Embolism/therapy , Lung , Tomography, X-Ray Computed/methods , Hemodynamics , Angioplasty, Balloon/methods , Chronic Disease , Pulmonary Artery
11.
Eur J Pediatr ; 171(3): 579-86, 2012 Mar.
Article in English | MEDLINE | ID: mdl-22083156

ABSTRACT

UNLABELLED: Our aim was to evaluate the feasibility of using computed tomography (CT) to define the pulmonary artery anatomy in patients with tetralogy of Fallot and pulmonary atresia (TOF-PA). We retrospectively reviewed 110 patients with TOF-PA between 1995 and 2008. Those who received cardiac catheterization and surgery within 3 months of their CT examinations were enrolled. Based on Dr. Somerville's classification, the pulmonary arterial pattern was determined, including identifiable pulmonary trunk (type I), the presence of both left and right pulmonary arteries without trunk (II), only left or right pulmonary artery present (III), and absent intrapericardial pulmonary arteries (IV). The accuracy of both imaging modalities was evaluated with operation findings as the golden standard. The effective radiation doses and adverse events were also recorded. In the 64 eligible patients (median age, 23 months), CT and catheterization demonstrated accurate pulmonary arterial morphology in 60 (60/64) and 53 (53/64) TOF-PA patients, respectively. Thirty-two of 35 type I patients were correctly identified by CT, whereas 26 were correctly identified by catheterization (p = 0.03). Of the 20 type II TOF-PA patients, 19 were diagnosed by CT, whereas 18 were diagnosed by catheterization. CT and catheterization both successfully defined six type III and three type IV patients. The median calculated radiation doses caused by CT and catheterization were 4.5 and 5.6 mSv, respectively (p > 0.05). CONCLUSIONS: For patients with TOF-PA, CT could accurately delineate pulmonary arterial morphology with the same level of accuracy as cardiac catheterization. Therefore, CT can be considered a reasonable diagnostic alternative for such patients.


Subject(s)
Abnormalities, Multiple/diagnostic imaging , Pulmonary Artery/diagnostic imaging , Pulmonary Atresia/diagnostic imaging , Tetralogy of Fallot/diagnostic imaging , Tomography, X-Ray Computed , Cardiac Catheterization , Child, Preschool , Feasibility Studies , Female , Humans , Infant , Male , Pulmonary Artery/abnormalities , Radiation Dosage , Retrospective Studies
12.
Eur J Radiol ; 157: 110596, 2022 Dec.
Article in English | MEDLINE | ID: mdl-36379098

ABSTRACT

PURPOSE: The utilization of diagnostic medical imaging has been growing worldwide. However, no study has investigated the trend in image utilization and the corresponding workload of radiologists under the National Healthcare Insurance (NHI) system with a code-bundling-based reimbursement strategy. We will analyse the trend in diagnostic imaging utilization and the corresponding workload of the radiologists at a single tertiary medical centre using the NHI system. MATERIALS AND METHODS: This was a retrospective study recruiting the diagnostic medical images, including X-rays, CT, and MR performed between 2005 and 2020 at a single medical centre. We investigated the change over time in image utilization and workload for interpreting the images. The two-sided Mann-Kendall test was used for the monotonic trend analysis and Sen's slope estimate was calculated for the annual mean change with the 95% confidence interval (CI). A P value < 0.05 was considered significant. RESULTS: A total of 10,069,583 examinations were performed at our institute from 2005 to 2020, including 7,821,880 X-rays, 1,665,787 CT, and 581,916 MR examinations. The numbers of examinations of X-rays, CT, and MR increased with average annual changes of 13,411.3 (95% CI = 11,875.0-14,773.8), 9,496.7 (95% CI = 8,845.3-9,828.7), and 2,417.1 (95% CI = 2,209.8-2,668.9) respectively, all P < 0.001. The proportion of cases including multiple examinations increased, growing from 21.5% (6,627 in 30,878 cases) to 43.8% (39,417 in 90,032 cases) for CT and from 8.9% (1,316 in 14,791 cases) to 15.7% (6,083 in 38,865 cases) for MR. The average time spent on interpreting each diagnostic image decreased significantly from 16.0 to 2.9 sec. (P < 0.001). CONCLUSION: Imaging utilization increased significantly under the NHI system at a medical centre. The corresponding demand for image interpretation also placed a significant workload on radiologists, potentially contributing to radiologist burnout.


Subject(s)
Magnetic Resonance Imaging , Tomography, X-Ray Computed , Humans , Retrospective Studies , Radiologists , Burnout, Psychological , National Health Programs
13.
Sci Rep ; 12(1): 16099, 2022 09 27.
Article in English | MEDLINE | ID: mdl-36167958

ABSTRACT

Dynamic duplex sonography (DUS) is not comprehensive in the evaluation of arteriogenic erectile dysfunction (ED). We introduced a new parameter, the flow index (FI), into the assessment of arteriogenic ED. A retrospective review of a prospective database was conducted. Patients undergoing DUS and pelvic computed tomography angiography for the evaluation of ED were included. The FI was calculated from peak systolic velocity (PSV) and the percentages of pelvic arterial (PLA) stenosis. Correlations between PSV, PLA stenosis, the FI, and erectile function were calculated. Eighty-three patients were included. Compared with PSV, the FI had better correlations with the erection hardness score (EHS) (rs = 0.405, P < 0.001 for FI; rs = 0.294, P = 0.007 for PSV). For EHS < 3, the areas under the ROC curve of FI and PSV were 0.759 and 0.700, respectively. In patients with normal DUS but EHS < 3, PLA stenosis was more severe (62.5% vs. 10.0%, P = 0.015), and the FI was lower (8.35 vs. 57.78, P = 0.006), while PSV was not different. The FI is better than PSV in the evaluation of arteriogenic ED. On the other hand, assessment of the pelvic arterial system should be included in the evaluation of ED.


Subject(s)
Erectile Dysfunction , Blood Flow Velocity/physiology , Constriction, Pathologic , Erectile Dysfunction/diagnostic imaging , Humans , Male , Penile Erection/physiology , Polyesters
14.
Opt Express ; 19(20): 19523-31, 2011 Sep 26.
Article in English | MEDLINE | ID: mdl-21996893

ABSTRACT

Based on tissues from 20 female patients (mean age: 53 years; rang: 36-72 years), we examine the performance of a room-temperature-operated terahertz (THz) fiber-scanning near-field microscopy to diagnose slices of breast tissues. The specimens were frozen sliced and then measured in a thawed state without dehydration. We performed the imaging at 320 GHz. Our study indicates that images acquired in the THz transmission-illumination mode can all clearly distinguish breast tumor tissues from normal tissues without H&E staining. Due to its capability to perform quantitative analysis and to allow follow-up staining and traditional pathohistological analysis, our study indicates great potential of the THz fiber-scanning near-field microscopy for future automation, which is critical for fast and complete pre-screening on breast tumor pathological examinations and for assisting quick definition of the tumor margins during the surgical procedure such as breast-conserving surgery.


Subject(s)
Breast Neoplasms/pathology , Breast/pathology , Microscopy, Atomic Force/methods , Terahertz Spectroscopy/methods , Adult , Aged , Female , Humans , Middle Aged
15.
Opt Express ; 19(22): 21552-62, 2011 Oct 24.
Article in English | MEDLINE | ID: mdl-22109004

ABSTRACT

We performed in vivo THz transmission imaging study on a subcutaneous xenograft mouse model for early human breast cancer detection. With a THz-fiber-scanning transmission imaging system, we continuously monitored the growth of human breast cancer in mice. Our in vivo study not only indicates that THz transmission imaging can distinguish cancer from the surrounding fatty tissue, but also with a high sensitivity. Our in vivo study on the subcutaneous xenograft mouse model will encourage broad and further investigations for future early cancer screening by using THz imaging system.


Subject(s)
Breast Neoplasms/diagnosis , Diagnostic Imaging/methods , Early Detection of Cancer/methods , Subcutaneous Tissue/pathology , Xenograft Model Antitumor Assays , Absorption , Animals , Breast Neoplasms/pathology , Female , Humans , Magnetic Resonance Imaging , Mice , Mice, Inbred BALB C , Spectrum Analysis
16.
Korean J Radiol ; 22(4): 493-501, 2021 04.
Article in English | MEDLINE | ID: mdl-33686819

ABSTRACT

The Asian Society of Cardiovascular Imaging (ASCI) was established in 2006 to improve the healthcare, education, training, quality control, and research in cardiovascular imaging in Asia. The ASCI is presently active, with more than 1400 members from 53 countries. Herein, the evolution and current development of the ASCI are described, including the early history, organization, annual congresses, collaboration with international sister societies, official journal, and the ASCI School. The ASCI has successfully led the development of cardiovascular imaging in Asia and will continue to grow.


Subject(s)
Coronary Artery Disease/diagnostic imaging , Societies, Medical/history , Congresses as Topic , Coronary Artery Disease/diagnosis , Diagnostic Imaging , History, 21st Century , Humans , Societies, Medical/organization & administration
17.
Sci Rep ; 11(1): 13855, 2021 07 05.
Article in English | MEDLINE | ID: mdl-34226598

ABSTRACT

This study aims to apply a CCTA-derived territory-based patient-specific estimation of boundary conditions for coronary artery fractional flow reserve (FFR) and wall shear stress (WSS) simulation. The non-invasive simulation can help diagnose the significance of coronary stenosis and the likelihood of myocardial ischemia. FFR is often regarded as the gold standard to evaluate the functional significance of stenosis in coronary arteries. In another aspect, proximal wall shear stress ([Formula: see text]) can also be an indicator of plaque vulnerability. During the simulation process, the mass flow rate of the blood in coronary arteries is one of the most important boundary conditions. This study utilized the myocardium territory to estimate and allocate the mass flow rate. 20 patients are included in this study. From the knowledge of anatomical information of coronary arteries and the myocardium, the territory-based FFR and the [Formula: see text] can both be derived from fluid dynamics simulations. Applying the threshold of distinguishing between significant and non-significant stenosis, the territory-based method can reach the accuracy, sensitivity, and specificity of 0.88, 0.90, and 0.80, respectively. For significantly stenotic cases ([Formula: see text] [Formula: see text] 0.80), the vessels usually have higher wall shear stress in the proximal region of the lesion.


Subject(s)
Coronary Artery Disease/diagnosis , Coronary Stenosis/diagnosis , Coronary Vessels/physiopathology , Fractional Flow Reserve, Myocardial/physiology , Aged , Computed Tomography Angiography , Coronary Artery Disease/diagnostic imaging , Coronary Artery Disease/pathology , Coronary Stenosis/diagnostic imaging , Coronary Stenosis/pathology , Coronary Vessels/diagnostic imaging , Female , Hemodynamics , Humans , Male , Myocardial Ischemia/diagnosis , Myocardial Ischemia/diagnostic imaging , Myocardial Ischemia/pathology , Plaque, Atherosclerotic/diagnosis , Plaque, Atherosclerotic/diagnostic imaging , Plaque, Atherosclerotic/pathology , Stress, Mechanical
18.
Diagnostics (Basel) ; 12(1)2021 Dec 31.
Article in English | MEDLINE | ID: mdl-35054260

ABSTRACT

This prospective study aimed to investigate the ability of spiral ultrashort echo time (UTE) and compressed sensing volumetric interpolated breath-hold examination (CS-VIBE) sequences in magnetic resonance imaging (MRI) compared to conventional VIBE and chest computed tomography (CT) in terms of image quality and small nodule detection. Patients with small lung nodules scheduled for video-assisted thoracoscopic surgery (VATS) for lung wedge resection were prospectively enrolled. Each patient underwent non-contrast chest CT and non-contrast MRI on the same day prior to thoracic surgery. The chest CT was performed to obtain a standard reference for nodule size, location, and morphology. The chest MRI included breath-hold conventional VIBE and CS-VIBE with scanning durations of 11 and 13 s, respectively, and free-breathing spiral UTE for 3.5-5 min. The signal-to-noise ratio (SNR), contrast-to-noise ratio (CNR), and normal structure visualizations were measured to evaluate MRI quality. Nodule detection sensitivity was evaluated on a lobe-by-lobe basis. Inter-reader and inter-modality reliability analyses were performed using the Cohen κ statistic and the nodule size comparison was performed using Bland-Altman plots. Among 96 pulmonary nodules requiring surgery, the average nodule diameter was 7.7 ± 3.9 mm (range: 4-20 mm); of the 73 resected nodules, most were invasive cancer (74%) or pre-invasive carcinoma in situ (15%). Both spiral UTE and CS-VIBE images achieved significantly higher overall image quality scores, SNRs, and CNRs than conventional VIBE. Spiral UTE (81%) and CS-VIBE (83%) achieved a higher lung nodule detection rate than conventional VIBE (53%). Specifically, the nodule detection rate for spiral UTE and CS-VIBE reached 95% and 100% for nodules >8 and >10 mm, respectively. A 90% detection rate was achieved for nodules of all sizes with a part-solid or solid morphology. Spiral UTE and CS-VIBE under-estimated the nodule size by 0.2 ± 1.4 mm with 95% limits of agreement from -2.6 to 2.9 mm and by 0.2 ± 1.7 mm with 95% limits of agreement from -3.3 to 3.5 mm, respectively, compared to the reference CT. In conclusion, chest CT remains the gold standard for lung nodule detection due to its high image resolutions. Both spiral UTE and CS-VIBE MRI could detect small lung nodules requiring surgery and could be considered a potential alternative to chest CT; however, their clinical application requires further investigation.

19.
Sci Rep ; 11(1): 10360, 2021 05 14.
Article in English | MEDLINE | ID: mdl-33990651

ABSTRACT

We report the first Asian series on stereotactic body radiation (SBRT) for refractory ventricular arrhythmia (VA) in Taiwanese patients. Three-dimensional electroanatomic maps, delayed-enhancement magnetic resonance imaging (DE-MRI), and dual-energy computed tomography (CT) were used to identify scar substrates. The main target volume was treated with a single radiation dose of 25 Gy and the margin volume received 20 Gy using simultaneous integrated boost delivered by the Varian TrueBeam system. Efficacy was assessed according to VA events recorded by an implantable cardioverter-defibrillator (ICD) or a 24-h Holter recorder. Pre- and post-radiation therapy imaging studies were performed. From February 2019 to December 2019, seven patients (six men, one woman; mean age, 55 years) were enrolled and treated. One patient died of hepatic failure. In the remaining six patients, at a median follow-up of 14.5 months, the VA burden and ICD shocks significantly decreased (only one patient with one ICD shock after treatment). Increased intensity on DE-MRI might be associated with a lower risk for VA recurrence, whereas dual-energy CT had lower detection sensitivity. No acute or minimal late adverse events occurred. In patients with refractory VA, SBRT is associated with a marked reduction in VA burden and ICD shocks, and DE-MRI might be useful for monitoring treatment effects.


Subject(s)
Arrhythmias, Cardiac/therapy , Cicatrix/surgery , Defibrillators, Implantable/statistics & numerical data , Heart/diagnostic imaging , Radiosurgery/statistics & numerical data , Arrhythmias, Cardiac/diagnosis , Arrhythmias, Cardiac/pathology , Cicatrix/diagnosis , Cicatrix/pathology , Female , Follow-Up Studies , Humans , Magnetic Resonance Imaging/methods , Male , Middle Aged , Myocardium/pathology , Radiosurgery/adverse effects , Taiwan , Tomography, X-Ray Computed/methods , Treatment Outcome
20.
J Clin Endocrinol Metab ; 94(2): 662-9, 2009 Feb.
Article in English | MEDLINE | ID: mdl-19050055

ABSTRACT

CONTEXT: Epicardial adipose tissue (EAT) is a metabolically active visceral fat depot. Its distribution is asymmetrical and primarily concentrated in the grooves. To date, it remains unclear which measurement of EAT best reflects its metabolic risk. OBJECTIVE: We aimed to examine the correlations between various multidetector computed tomographic measurements of EAT, metabolic syndrome components, and plasma levels of high-sensitivity C-reactive protein and adipokines. DESIGN, SETTING, AND PARTICIPANTS: This study included 148 consecutive patients undergoing multidetector computed tomography prior to diagnostic coronary angiography. Thickness in the grooved segments, cross-sectional areas, and total volume of EAT were measured. The cross-sectional areas of sc and visceral abdominal fat depots were additionally measured in 70 randomly selected patients. RESULTS: Thickness of EAT in the left atrioventricular groove was the only EAT measurement significantly correlated with all three metabolic syndrome components (blood pressure, lipid, and glucose components) and plasma levels of resistin and high-sensitivity C-reactive protein after age and gender adjustments. The association between left atrioventricular groove thickness and increasing number of metabolic syndrome components remained significant after additional adjustments for body mass index, waist circumference, and intraabdominal visceral fat area. By using the receiver operating characteristic analysis, the optimal cutoff point for left atrioventricular groove thickness to predict the presence of at least two metabolic syndrome components was 12.4 mm. CONCLUSIONS: A simple measurement of EAT thickness in the left atrioventricular groove may provide a more accurate assessment of metabolic risk associated with EAT, which could not be accounted for by anthropometric indexes and intraabdominal visceral fat.


Subject(s)
Adipose Tissue/pathology , Body Weights and Measures , Health Status Indicators , Intra-Abdominal Fat/pathology , Metabolic Syndrome/diagnostic imaging , Pericardium , Adipose Tissue/diagnostic imaging , Female , Humans , Male , Metabolic Syndrome/etiology , Metabolic Syndrome/pathology , Middle Aged , Organ Specificity , Risk Factors , Tomography, X-Ray Computed/methods
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