Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 65
Filtrar
1.
Mol Imaging Biol ; 2024 Oct 10.
Artículo en Inglés | MEDLINE | ID: mdl-39390273

RESUMEN

PURPOSE: To evaluate the value of Tc-99m-diethylenetriamine-penta-acetic acid-galactosyl human serum albumin (99mTc-GSA) single photon emission computed tomography (SPECT) for assessing liver fibrosis, and to assess its complementary value to other liver function indices such as fibrosis-4 (FIB-4) index and indocyanine green (ICG) clearance test parameters (ICG-R15 and ICG-K). PROCEDURES: Seventy-eight patients with chronic liver disease and hepatocellular carcinoma who underwent 99mTc-GSA scintigraphy and other liver function tests including ICG test and FIB-4 index prior to hepatectomy were studied. 99mTc-GSA imaging was performed with SPECT/CT scanner (Discovery NM/CT 670). Immediately after injection of 99mTc-GSA, dynamic imaging was performed for 20 min, followed by SPECT data acquisition for 6 min. LHL15 which is a conventional index by 99mTc-GSA planar images, and liver uptake ration (LUR) was measured from 99mTc-GSA SPECT images. From the liver resection specimens, the degree of liver fibrosis was graded according to the Ludwig scale (F0-4). RESULTS: Significant differences in LUR, LHL15, ICG-R15, ICG-K, platelet count and FIB-4 index were found between the F0-3 and F4 liver fibrosis patient groups (P < 0.05). Multivariate logistic regression analysis revealed that LUR and ICG-K were independent factors for identifying severe liver fibrosis (F4). Area under the curve of receiver operating curve analysis for the logistic regression model using LUR and ICG-K was 0.83. In the patient group with higher FIB-4 (≥ 3.16), the diagnostic performance of LUR for detecting severe liver fibrosis was significantly better than LHL15 (AUC: 0.83 vs. 0.75, P = 0.048). In the high FIB-4 index group, the sensitivity and specificity for identifying F4 was 88% and 85%, respectively, with LUR cutoff value of 41.2%. CONCLUSIONS: LUR, measured by 99mTc-GSA SPECT, is a useful indicator for identifying sever liver fibrosis. Particularly in patients with high FIB-4 index (≥ 3.16), LUR can be a valuable indicator to identify severe liver fibrosis with high diagnostic accuracy.

2.
Ann Vasc Dis ; 17(3): 248-254, 2024 Sep 25.
Artículo en Inglés | MEDLINE | ID: mdl-39359567

RESUMEN

Objectives: This study aims to investigate the efficacy of thoracic endovascular aortic repair (TEVAR) for type B aortic dissection (TBAD) complicated by malperfusion. Methods: This retrospective study included patients who underwent TEVAR for the treatment of TBAD complicated by malperfusion from June 1998 to June 2022 in four institutions. In addition to the common outcomes, including short- and medium-term mortality and morbidity, the preservation of each organ was investigated. Results: A total of 23 patients were included in this analysis. The 30-day mortality was 4% (1/23) of the patients. The overall survival rate was 87% at 1 year. The preservation rate of each organ was 33% (4/12) for the visceral organs, 85% (17/20) for the kidneys, and 100% (18/18) for the legs. Fisher's exact test showed a significant difference in the preservation rate between the viscera and the other organs (P = 0.018 vs. kidneys, P = 0.0025 vs. legs). It was shown that the survival rate of patients with visceral malperfusion was significantly lower than that of patients with non-visceral malperfusion (P = 0.006). Conclusion: In terms of mortality, TEVAR showed satisfactory results. The preservation of visceral organs was still challenging even with TEVAR and adjunctive measures.

3.
J Vasc Interv Radiol ; 2024 Oct 18.
Artículo en Inglés | MEDLINE | ID: mdl-39428062

RESUMEN

PURPOSE: The aim of study is to investigate the efficacy of thoracic endovascular aortic repair for infectious aortic diseases. MATERIALS AND METHODS: Patients who underwent thoracic endovascular repair for infectious aortic diseases including mycotic thoracic aortic aneurysm, aorto-bronchial fistula and aorto-enteric fistula from December 2011 to October 2022 at four institutions were retrospectively studied. The primary outcome of the study was overall survival, whereas the secondary outcome was comprehensive adverse event. Comprehensive adverse events were defined as a combination of deaths, aortic events, and infectious adverse events. RESULTS: A total of 28 patients were included in the analysis, with 13 patients having mycotic thoracic aortic aneurysms, 12 having aorto-bronchial fistulas, and 3 having aorto-enteric fistulas. Seven patients (25%) underwent additional procedures (abscess drainage, 6 cases; total esophagectomy, 1 case). The mean follow-up period was 30.0 ± 33.9 months. The 1-year and 5-year survival rates were 85.7% and 67.9%, respectively. The 1-year and 5-year aorta-related complication-free survival rates were 64.3% and 42.9%, respectively. On univariate analysis, the presence of an aorto-bronchial fistula was associated with a higher risk of comprehensive adverse events (odds ratio [OR] = 11, P = 0.04). CONCLUSION: TEVAR might be a promising treatment for infectious thoracic aortic diseases. Among the infectious pathologies, ABF was considered ominous in terms of late outcomes.

4.
Artículo en Inglés | MEDLINE | ID: mdl-39271165

RESUMEN

OBJECTIVES: Physician's evaluation of interstitial lung disease (ILD) extension with high-resolution computed tomography (HRCT) has limitations such as lack of objectivity and reproducibility. This study aimed to investigate the utility of computer-based deep-learning analysis using QZIP-ILD® software (DL-QZIP) compared with conventional approaches in connective tissue disease (CTD) -related ILD. METHODS: Patients with CTD-ILD visiting our Rheumatology Centre between December 2020 and April 2024 were recruited. Quantitative scores, including the percentage of lung involvement in ground-glass opacity (QGG), total fibrotic lesion (QFIB), and overall ILD extension encompassing both QGG and QFIB (QILD), calculated by DL-QZIP, were compared with semiquantitative visual method, employing intraclass correlation coefficients (ICC). We compared the capability of QILD scores to distinguish patients with forced vital capacity (FVC) % <70 in both methods determined by the area under the curve (AUC) by the receiver-operating characteristic curve analysis and DeLong's test. RESULTS: Eighty patients (median age, 66 years; 14 men) were included. Median QGG, QFIB, and QILD scores were 3.45%, 2.19%, and 5.35% using DL-QZIP, and 3.25%, 4.06%, and 8.48% using visual method, respectively. Correlations between DL-QZIP and visual method were 0.75 for QGG, 0.61 for QFIB, and 0.75 for QILD. The AUC of QILD scores for FVC% <70 was significantly higher with DL-QZIP (0.833) compared with visual method (0.660) (p < 0.01). CONCLUSION: QZIP-ILD® demonstrates superior capability in distinguishing patients with a radiological scenario correlated to severe physiological impairment, while showing relatively good correlations in quantifying the extent on HRCT compared with conventional method in CTD-ILD.

5.
J Imaging Inform Med ; 2024 Aug 13.
Artículo en Inglés | MEDLINE | ID: mdl-39136827

RESUMEN

To evaluate the usefulness of low-keV multiphasic computed tomography (CT) with deep learning image reconstruction (DLIR) in improving the delineation of pancreatic ductal adenocarcinoma (PDAC) compared to conventional hybrid iterative reconstruction (HIR). Thirty-five patients with PDAC who underwent multiphasic CT were retrospectively evaluated. Raw data were reconstructed with two energy levels (40 keV and 70 keV) of virtual monochromatic imaging (VMI) using HIR (ASiR-V50%) and DLIR (TrueFidelity-H). Contrast-to-noise ratio (CNRtumor) was calculated from the CT values within regions of interest in tumor and normal pancreas in the pancreatic parenchymal phase images. Lesion conspicuity of PDAC in pancreatic parenchymal phase on 40-keV HIR, 40-keV DLIR, and 70-keV DLIR images was qualitatively rated on a 5-point scale, using 70-keV HIR images as reference (score 1 = poor; score 3 = equivalent to reference; score 5 = excellent) by two radiologists. CNRtumor of 40-keV DLIR images (median 10.4, interquartile range (IQR) 7.8-14.9) was significantly higher than that of the other VMIs (40 keV HIR, median 6.2, IQR 4.4-8.5, P < 0.0001; 70-keV DLIR, median 6.3, IQR 5.1-9.9, P = 0.0002; 70-keV HIR, median 4.2, IQR 3.1-6.1, P < 0.0001). CNRtumor of 40-keV DLIR images were significantly better than those of the 40-keV HIR and 70-keV HIR images by 72 ± 22% and 211 ± 340%, respectively. Lesion conspicuity scores on 40-keV DLIR images (observer 1, 4.5 ± 0.7; observer 2, 3.4 ± 0.5) were significantly higher than on 40-keV HIR (observer 1, 3.3 ± 0.9, P < 0.0001; observer 2, 3.1 ± 0.4, P = 0.013). DLIR is a promising reconstruction method to improve PDAC delineation in 40-keV VMI at the pancreatic parenchymal phase compared to conventional HIR.

6.
J Innov Card Rhythm Manag ; 15(7): 5936-5944, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-39011460

RESUMEN

The effect of irradiation during computed tomography (CT) imaging on implantable cardioverter-defibrillators (ICDs) has not been fully evaluated in various settings. The purposes of this study were to evaluate the occurrence of electromagnetic interference (EMI) during CT irradiation in various clinically available ICDs with phantom experiments and to determine the potential risks related to irradiation during CT imaging. Five types of clinically available ICDs from five manufacturers were tested. An ICD was combined with an electrocardiogram (ECG) simulator, mounted in a chest phantom, and subjected to CT imaging. Each ICD was irradiated at the maximal power level (tube voltage, 135 kVp; tube current, 510 mA; rotation time, 1.5 s). EMI was defined as oversensing, ventricular tachycardia/ventricular fibrillation (VT/VF) detection, noise, or shock delivery during CT imaging. For ICDs in which EMI was observed, EMI was then evaluated under 144 different irradiation conditions (tube voltage [four patterns from 80-135 kVp], tube current [six patterns from 50-550 mA], and rotation time [six patterns from 0.35-1.5 s]). Testing was also performed during irradiation at the typical doses in three clinical settings and in two settings with inappropriate irradiation of ICDs due to incorrect setup. Among the five ICDs, a shock was delivered by one ICD manufactured by Medtronic (Minneapolis, MN, USA) due to oversensing during irradiation, which occurred at the maximal power level. No oversensing was observed in other ICDs. In the malfunctioned ICD, oversensing was observed in 134 of 144 irradiation patterns, even at a low power in the ICD. The VF-detection criterion was fulfilled in 20 of 134 tests and was significantly associated with tube voltage, tube current, ration time, and tube voltage × rotation time interaction. Although oversensing was observed in three clinical settings (typical chest CT, CT coronary angiography after coronary artery bypass graft, and dynamic assessment for pleural tumors) and one situation during an incorrect scan range on the chest for head perfusion CT, they were not recognized as tachycardia beats. Oversensing was observed when scans were incorrectly set over the ICD during bolus tracking of contrast-enhanced CT. Maximal power CT imaging induced VT/VF detection and shock delivery in one model of ICD placed in a chest phantom. VT/VF detection was observed when tube voltages were high and irradiation times were longer. Oversensing can occur during inappropriate CT imaging, particularly when slices are positioned over the ICD.

7.
Arthritis Res Ther ; 26(1): 95, 2024 May 04.
Artículo en Inglés | MEDLINE | ID: mdl-38704556

RESUMEN

OBJECTIVES: Rheumatoid arthritis (RA) related interstitial lung disease (ILD) impacts on the treatment strategy and its prognosis in patients with RA. However, the relationship between RA disease activity and the severity of comorbid ILD has not been fully investigated. This study aimed to investigate the impact of RA disease activity on the severity of comorbid ILD in detail based on currently established visual scoring method along with physiological severity. METHODS: Consecutive patients with RA visiting to our Rheumatology Centre between December 2020 and December 2023 were analysed. The radiological severity of ILD was evaluated by averaging the extent of the combined lesion of ground glass opacity, reticulation and honeycombing in 5% increments in six representative high-resolution computed tomography slices ranging from 0% (no involvement) to 100% (all lung fields affected) according to Goh and Walsh's method. Associations between the radiological and physiological severity of ILD and patients' features were investigated using linear regression analysis. RESULTS: Among 124 patients (32 men, 92 women), the median age was 70 years, and the median disease duration was 2.92 years. Radiological severity of ILD was 0% (without ILD) in 107 (86.2%), ILD with extent < 10% in nine (7.2%), ILD with extent ≥10% and < 20% in three (2.4%), ILD with extent ≥20% in five (4.0%). Both disease activity score (DAS)28-erythrocyte sedimentation rate (ESR) (standardized coefficient = 0.199, P = 0.03) and rheumatoid factor titre (standardized coefficient = 0.247, P = 0.01) were significantly associated with the radiological quantitative severity of ILD in multivariate analysis adjusted for age, sex, disease duration, smoking status and anti-citrullinated peptide antibody titre. DAS28-ESR was significantly associated with forced vital capacity% predicted (standardized coefficient = -0.230, P = 0.047). CONCLUSIONS: Disease activity of RA was significantly associated with the severity of RA-ILD both radiologically and physiologically.


Asunto(s)
Artritis Reumatoide , Enfermedades Pulmonares Intersticiales , Índice de Severidad de la Enfermedad , Humanos , Artritis Reumatoide/complicaciones , Artritis Reumatoide/diagnóstico por imagen , Enfermedades Pulmonares Intersticiales/diagnóstico , Enfermedades Pulmonares Intersticiales/diagnóstico por imagen , Masculino , Femenino , Anciano , Persona de Mediana Edad , Tomografía Computarizada por Rayos X/métodos , Estudios Retrospectivos , Anciano de 80 o más Años
8.
Surg Today ; 54(8): 953-963, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38581555

RESUMEN

PURPOSE: Predicting nonalcoholic fatty liver disease (NAFLD) following pancreaticoduodenectomy (PD) is challenging, which delays therapeutic intervention and makes its prevention difficult. We conducted this study to assess the potential application of preoperative computed tomography (CT) radiomics for predicting NAFLD. METHODS: The subjects of this retrospective study were 186 patients with PD from a single institution. We extracted the predictors of NAFLD after PD statistically from conventional clinical and radiomic features of the estimated remnant pancreas and whole liver region on preoperative nonenhanced CT images. Based on these predictors, we developed a machine-learning predictive model, which integrated clinical and radiomic features. A comparative model used only clinical features as predictors. RESULTS: The incidence of NAFLD after PD was 43.5%. The variables of the clinicoradiomic model included one shape feature of the pancreas, two texture features of the liver, and sex; the variables of the clinical model were age, sex, and chemoradiotherapy. The accuracy%, precision%, recall%, F1 score, and area under the curve of the two models were 75.0, 72.7, 66.7, 69.6, and 0.80; and 69.6, 68.4, 54.2, 60.5, and 0.69, respectively. CONCLUSIONS: Preoperative CT-derived radiomic features from the pancreatic and liver regions are promising for the prediction of NAFLD post-PD. Using these features enhances the predictive model, enabling earlier intervention for high-risk patients.


Asunto(s)
Enfermedad del Hígado Graso no Alcohólico , Pancreaticoduodenectomía , Complicaciones Posoperatorias , Tomografía Computarizada por Rayos X , Humanos , Pancreaticoduodenectomía/efectos adversos , Enfermedad del Hígado Graso no Alcohólico/diagnóstico por imagen , Enfermedad del Hígado Graso no Alcohólico/etiología , Masculino , Estudios Retrospectivos , Femenino , Persona de Mediana Edad , Complicaciones Posoperatorias/etiología , Complicaciones Posoperatorias/diagnóstico por imagen , Complicaciones Posoperatorias/epidemiología , Anciano , Aprendizaje Automático , Valor Predictivo de las Pruebas , Páncreas/diagnóstico por imagen , Páncreas/patología , Adulto , Hígado/diagnóstico por imagen , Hígado/patología , Periodo Preoperatorio , Incidencia , Anciano de 80 o más Años , Radiómica
10.
J Cardiovasc Comput Tomogr ; 18(3): 281-290, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38429130

RESUMEN

BACKGROUND: The purpose of this study was to investigate the usefulness of second-generation intra-cycle motion correction algorithm (SnapShot Freeze 2, GE Healthcare, MC2) in improving the delineation and interpretability of coronary arteries in coronary computed tomography angiography (CCTA) compared to first-generation intra-cycle motion correction algorithm (SnapShot Freeze, GE Healthcare, MC1). METHODS: Fifty consecutive patients with known or suspected coronary artery disease who underwent CCTA on a 256-slice CT scanner were retrospectively studied. CCTA were reconstructed with three different algorithms: no motion correction (NMC), MC1, and MC2. The delineation of coronary arteries on CCTA was qualitatively rated on a 5-point scale from 1 (nondiagnostic) to 5 (excellent) by two radiologists blinded to the reconstruction method and the patient information. RESULTS: On a per-vessel basis, the delineation scores of coronary arteries were significantly higher on MC2 images compared to MC1 images (median [interquartile range], right coronary artery, 5.0 [4.5-5.0] vs 4.5 [4.0-5.0]; left anterior descending artery, 5.0 [4.5-5.0] vs 4.5 [3.5-5.0]; left circumflex artery, 5.0 [4.5-5.0] vs 4.5 [3.9-5.0]; all p â€‹< â€‹0.05). On a per-segment basis, for both 2 observers, the delineation scores on segment 1, 2, 8, 9, 10, 12 and 13 on MC2 images were significantly better than those on MC1 images (p â€‹< â€‹0.05). The percentage of interpretable segments (rated score 3 or greater) on NMC, MC1, and MC2 images was 90.5-91.9%, 97.4-97.9%, and 100.0%, respectively. CONCLUSION: Second-generation intra-cycle motion correction algorithm improves the delineation and interpretability of coronary arteries in CCTA compared to first-generation algorithm.


Asunto(s)
Algoritmos , Artefactos , Angiografía por Tomografía Computarizada , Angiografía Coronaria , Enfermedad de la Arteria Coronaria , Vasos Coronarios , Valor Predictivo de las Pruebas , Interpretación de Imagen Radiográfica Asistida por Computador , Humanos , Femenino , Masculino , Angiografía Coronaria/métodos , Estudios Retrospectivos , Persona de Mediana Edad , Enfermedad de la Arteria Coronaria/diagnóstico por imagen , Anciano , Vasos Coronarios/diagnóstico por imagen , Reproducibilidad de los Resultados , Tomografía Computarizada Multidetector , Variaciones Dependientes del Observador
11.
Radiol Case Rep ; 19(5): 1708-1711, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38384705

RESUMEN

Epipericardial fat necrosis (EFN) is a rare benign cause of chest pain, that is frequently overlooked. EFN involves the necrosis of fat tissue in the mediastinum, and presents on computed tomography (CT) as an ovoid lesion of fat attenuation surrounded by a rim of soft tissue attenuation. This case report describes a case of a 50-year-old man diagnosed with EFN on cardiac CT, which was incidentally associated with apical hypertrophic myocardiopathy. Notably, the detection of EFN proved difficult on arterial phase images during coronary CT angiography, whereas it was much easier to detect on delayed phase images. EFN should be considered in the differential diagnosis of chest pain, and careful examination of mediastinal fat is crucial for accurate diagnosis.

13.
J Minim Invasive Gynecol ; 31(5): 445-452, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38417674

RESUMEN

STUDY OBJECTIVE: To assess the impact visceral adipose tissue percentage (VAT%) on surgical outcomes during minimally invasive surgery in obese women with endometrial cancer. DESIGN: Retrospective observational cohort study. SETTING: Mie University Hospital, Japan. PATIENTS: Of the 73 women (body mass index [BMI] >30 kg/m2) with obesity and primary endometrial cancer, 52 underwent robotic surgery, while 21 underwent laparoscopic surgery between April 2014 and December 2022. INTERVENTIONS: We investigated the correlation between surgical outcomes (operative time and blood loss) and obesity (BMI and visceral adipose tissue percentage [VAT%]). MEASUREMENTS AND MAIN RESULTS: Abdominal fat-related parameters were measured at the level of the umbilicus using preoperative computed tomography. A weak negative correlation was found between BMI and VAT% (CC = -0.313, p = .001). Multivariate analysis showed that VAT% had a stronger correlation to total and practical operative time than BMI (ß = 0.338 vs 0.267, ß = 0.311 vs 0.209, respectively) and was an independent predictor of blood loss. VAT% was an independent predictive marker prolonged for operative time and increased blood loss during lymphadenectomy. CONCLUSION: VAT% could be an indicator of surgical outcomes for patients with obesity and endometrial cancer.


Asunto(s)
Índice de Masa Corporal , Neoplasias Endometriales , Grasa Intraabdominal , Laparoscopía , Obesidad , Tempo Operativo , Humanos , Femenino , Neoplasias Endometriales/cirugía , Neoplasias Endometriales/patología , Neoplasias Endometriales/complicaciones , Grasa Intraabdominal/diagnóstico por imagen , Estudios Retrospectivos , Persona de Mediana Edad , Obesidad/complicaciones , Anciano , Laparoscopía/métodos , Procedimientos Quirúrgicos Robotizados/métodos , Pérdida de Sangre Quirúrgica , Resultado del Tratamiento , Japón/epidemiología , Escisión del Ganglio Linfático/métodos
14.
Vasc Endovascular Surg ; 58(4): 457-460, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38019846

RESUMEN

A 66-year-old man presented with hemolytic anemia, which required frequent blood transfusion, 6 months after surgical repair of an ascending aortic pseudoaneurysm. Hemolysis was attributed to luminal stenosis caused by graft kinking by laboratory test, CT and four-dimensional magnetic resonance imaging. First, an Excluder cuff was placed at the stenotic site under rapid pacing, but it migrated distally. Thereafter a Palmaz XL stent was placed at the stenotic site, which led to resolution of anemia. In this case, a Palmaz XL stent was successfully used to treat hemolytic anemia caused by graft kinking following ascending aortic surgery.


Asunto(s)
Anemia Hemolítica , Implantación de Prótesis Vascular , Procedimientos Endovasculares , Masculino , Humanos , Anciano , Prótesis Vascular/efectos adversos , Resultado del Tratamiento , Aorta/diagnóstico por imagen , Aorta/cirugía , Stents/efectos adversos , Implantación de Prótesis Vascular/efectos adversos , Anemia Hemolítica/diagnóstico por imagen , Anemia Hemolítica/etiología , Procedimientos Endovasculares/efectos adversos
15.
Radiol Case Rep ; 18(9): 3212-3217, 2023 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-37448598

RESUMEN

Mixed epithelial and stromal tumor (MEST) of the kidney is a rare benign tumor with malignant potential, and is characterized by epithelial and stromal proliferation with a variety of cellularity and growth pattern. MEST of the kidney is often depicted as a well-defined, solid mass with a cystic component. However, due to the rarity of the disease, there are no reports of its progression in serial imaging examinations. This report presents the case of a 68-year-old woman with MEST who was followed for 13 years by computed tomography (CT). To the best of our knowledge, this is the first report of image findings of MEST of the kidney over a follow-up period longer than 10 years.

16.
J Digit Imaging ; 36(5): 2313-2321, 2023 10.
Artículo en Inglés | MEDLINE | ID: mdl-37322307

RESUMEN

This study aims to determine the effect of Gaussian filter size for CT-based attenuation correction (CTAC) on the quantitative assessment of bone SPECT. An experiment was performed using a cylindrical phantom containing six rods, of which one was filled with water and five were filled with various concentrations of K2HPO4 solution (120-960 mg/cm3) to simulate different bone densities. 99mTc-solution of 207 kBq/ml was also included within the rods. SPECT data were acquired at 120 views for 30 s/view. CT for attenuation correction were obtained at 120 kVp and 100 mA. Sixteen different CTAC maps processed with different Gaussian filter sizes (ranging from 0 to 30 mm in 2 mm increments) were generated. SPECT images were reconstructed for each of the 16 CTAC maps. Attenuation coefficients and radioactivity concentrations in the rods were compared with those in the water-filled rod without K2HPO4 solution as a reference. Gaussian filter sizes below 14-16 mm resulted in an overestimation of radioactivity concentrations for rods with high concentrations of K2HPO4 (≥ 666 mg/cm3). The overestimation of radioactivity concentration measurement was 3.8% and 5.5% for 666 mg/cm3 and 960 mg/cm3 K2HPO4 solutions, respectively. The difference in radioactivity concentration between the water rod and the K2HPO4 rods was minimal at 18-22 mm. The use of Gaussian filter sizes smaller than 14-16 mm caused an overestimation of radioactivity concentration in regions of high CT values. Setting the Gaussian filter size to 18-22 mm enables radioactivity concentration to be measured with the least influence on bone density.


Asunto(s)
Tomografía Computarizada de Emisión de Fotón Único , Tomografía Computarizada por Rayos X , Humanos , Tomografía Computarizada por Rayos X/métodos , Huesos/diagnóstico por imagen , Densidad Ósea , Fantasmas de Imagen , Procesamiento de Imagen Asistido por Computador
17.
J Digit Imaging ; 36(4): 1578-1587, 2023 08.
Artículo en Inglés | MEDLINE | ID: mdl-36944812

RESUMEN

The purpose is to evaluate whether deep learning-based denoising (DLD) algorithm provides sufficient image quality for abdominal computed tomography (CT) with a 30% reduction in radiation dose, compared to standard-dose CT reconstructed with conventional hybrid iterative reconstruction (IR). The subjects consisted of 50 patients who underwent abdominal CT with standard dose and reconstructed with hybrid IR (ASiR-V50%) and another 50 patients who underwent abdominal CT with approximately 30% less dose and reconstructed with ASiR-V50% and DLD at low-, medium- and high-strength (DLD-L, DLD-M and DLD-H, respectively). The standard deviation of attenuation in liver parenchyma was measured as image noise. Contrast-to-noise ratio (CNR) for portal vein on portal venous phase was calculated. Lesion conspicuity in 23 abdominal solid mass on the reduced-dose CT was rated on a 5-point scale: 0 (best) to -4 (markedly inferior). Compared with hybrid IR of standard-dose CT, DLD-H of reduced-dose CT provided significantly lower image noise (portal phase: 9.0 (interquartile range, 8.7-9.4) HU vs 12.0 (11.4-12.7) HU, P < 0.0001) and significantly higher CNR (median, 5.8 (4.4-7.4) vs 4.3 (3.3-5.3), P = 0.0019). As for DLD-M of reduced-dose CT, no significant difference was found in image noise and CNR compared to hybrid IR of standard-dose CT (P > 0.99). Lesion conspicuity scores for DLD-H and DLD-M were significantly better than hybrid IR (P < 0.05). Dynamic contrast-enhanced abdominal CT acquired with approximately 30% lower radiation dose and generated with the DLD algorithm exhibit lower image noise and higher CNR compared to standard-dose CT with hybrid IR.


Asunto(s)
Aprendizaje Profundo , Humanos , Reducción Gradual de Medicamentos , Dosis de Radiación , Interpretación de Imagen Radiográfica Asistida por Computador/métodos , Tomografía Computarizada por Rayos X/métodos , Algoritmos
18.
Ann Nucl Med ; 37(6): 360-370, 2023 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-36947324

RESUMEN

PURPOSE: To evaluate the prognostic value of the quantitative assessment of 99mTc-methylene diphosphonate (99mTc-MDP) bone SPECT/CT in castration-resistant prostate cancer (CRPC) patients with bone metastases. METHODS: A total of 103 patients who underwent 99mTc-MDP bone SPECT/CT imaging from the neck to the proximal femur were included. First, in 65 patients without bone metastases, the normal range of standardized uptake value (SUV) of non-pathological bone was evaluated to determine an SUV threshold to reliably exclude most normal osseous activity. Then, in 38 CRPC patients with bone metastases, lesion uptake volume (LUV), which is the extracted volume of bone metastases exhibiting high accumulation above the SUV threshold, was calculated. The relation between LUV and prostate-related mortality was statistically evaluated. RESULTS: Based on the SUV measurements of non-pathological bones, the optimal SUV threshold, which defines abnormal bone SPECT uptake, was determined to be 8. Median LUV was 39 mL (interquartile range 4.0-104.3 mL) in the CRPC subjects with bone metastases. Kaplan-Meier survival analysis showed a significant relation between prostate cancer-specific survival and LUV (cut-off value, 19.95 mL; P = 0.001). Multivariate analysis revealed LUV as an independent prognostic factor for the survival (P = 0.008, hazard ratio 23.424). Global chi-square test showed that LUV had significant incremental prognostic value in addition to prostate-specific antigen and the interval from progression to CRPC until bone SPECT/CT (P = 0.022). CONCLUSION: Quantitative assessment of 99mTc-MDP bone SPECT images can provide valuable prognostic information in CRPC patients with bone metastases.


Asunto(s)
Neoplasias Óseas , Neoplasias de la Próstata Resistentes a la Castración , Masculino , Humanos , Neoplasias de la Próstata Resistentes a la Castración/diagnóstico por imagen , Estudios Retrospectivos , Pronóstico , Tomografía Computarizada por Tomografía Computarizada de Emisión de Fotón Único , Tomografía Computarizada de Emisión de Fotón Único/métodos , Neoplasias Óseas/diagnóstico por imagen , Neoplasias Óseas/secundario , Castración , Medronato de Tecnecio Tc 99m
20.
Magn Reson Med Sci ; 2022 Dec 13.
Artículo en Inglés | MEDLINE | ID: mdl-36517009

RESUMEN

PURPOSE: Pulmonary emphysema may associate with ischemic heart disease through systemic microvascular abnormality as a common pathway. Stress cardiovascular MR (CMR) allows for the assessment of global coronary flow reserve (CFR). The purpose of this study was to evaluate the association between the emphysema severity and the multiple MRI parameters in the emphysema patients with known or suspected coronary artery disease (CAD). METHODS: A total of 210 patients with known or suspected CAD who underwent both 3.0T CMR including cine CMR, stress and rest perfusion CMR, stress and rest phase-contrast (PC) cine CMR of coronary sinus, and late gadolinium enhancement (LGE) CMR, and lung CT within 6 months were studied. Global CFR, volumes and functions of both ventricles and atria, and presence or absence of myocardial ischemia and infarction were evaluated. Emphysema severity was visually determined on lung CT by Goddard method. RESULT: Seventy nine (71.0 ± 7.9 years, 75 male) of 210 patients with known or suspected CAD had emphysema on lung CT. Goddard score was significantly correlated with CFR (r = -0.246, P = 0.029), left ventricular end-diastolic volume index (LV EDVI) (r = -0.230, P = 0.041), right ventricular systolic volume index (RV SVI) (r = -0.280, P = 0.012), left atrial (LA) total emptying volume index (r = -0.269, P = 0.017), LA passive emptying volume index (r = -0.309, P = 0.006), LA systolic strain (Es) (r = -0.244, P = 0.030), and LA conduit strain (Ee) (r = -0.285, P = 0.011) in the patients with emphysema. Multiple linear regression analysis revealed LA conduit function was independently associated with emphysema severity as determined by Goddard method (beta = -0.361, P = 0.006). CONCLUSION: LA conduit function independently associates with emphysema severity in the emphysema patients with known or suspected CAD after adjusting age, sex, smoking, and the CMR indexes including CFR. These findings suggest that impairment of LA function predominantly occurs prior to the reduction of the CFR in the emphysema patients with known or suspected CAD.

SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA
...