Ultrasonography最新文献

Purpose: This study aimed to develop and evaluate a near-infrared spectroscopy (NIRS) system enhanced by gold nanorods (GNRs) for the detection of prostate cancer using phantom and xenograft mouse models.

Methods: A hybrid ultrasound-NIRS (US-NIRS) system was created with a 785 nm wavelength, integrating eight laser diodes and four detectors with a linear ultrasound probe. Software for processing near-infrared (NIR) signals was developed using an engineering toolkit and an image reconstruction package. Two optical phantoms simulating prostate cancer were constructed using TiO2 for scattering effects and India ink for absorption effects, each containing a cylindrical cavity for GNRs positioned at depths of 1 cm and 2 cm. A xenograft mouse model was prepared by injecting PC-3 cells into the right flank of nude mice. PEGylated GNRs (GNR-PEG) were synthesized. US-NIRS imaging was performed on mice before and after intravenous injection of GNR-PEG.

Results: Ultrasonography revealed solid, vascular tumors without necrosis or hemorrhage. Preinjection NIRS showed higher baseline NIR absorbance in tumors compared to normal tissue (optical depths: 0.26, 1.52, and 0.24 for the 1.5 cm, 1.4 cm, and 0.5 cm tumors, respectively). After GNR-PEG injection, tumor optical depths significantly increased (3.36, 4.39, and 1.69 for the 1.5 cm, 1.4 cm, and 0.5 cm tumors, respectively), peaking around 5 minutes, and subsequently decreasing towards baseline levels by 60 minutes.

Conclusion: A US-NIRS hybrid imaging system enhanced by GNR-PEG demonstrated increased NIR absorption in prostate cancer xenografts. This fusion imaging technique holds potential for future clinical applications in detecting prostate cancer.

Purpose: This study aimed to evaluate whether an immediate short waiting period after radiofrequency ablation (RFA) can improve the accuracy of ultrasound (US)-based assessment of the ablation zone in patients with hepatocellular carcinoma (HCC).

Methods: A prospective cohort study was conducted involving 41 patients who underwent US-guided RFA for HCC. Tumor margin conspicuity, electrode tip visibility, and operator confidence in assessing the ablative margin were recorded immediately following electrode deactivation and at 1-minute intervals for 5 minutes. Post-ablation computed tomography was performed to confirm the sufficiency of the ablative margins. The Friedman test and post-hoc Conover analysis were used to assess changes over time.

Results: Over time, significant improvements were observed in tumor margin visibility, electrode tip visualization, and operator confidence in ablative margin assessment (all P<0.001). Repositioning and additional ablation were required in 29.3% (12/41) of patients, with all achieving sufficient ablative margins. Larger tumor size was associated with decreased operator confidence (P=0.008). No major complications occurred.

Conclusion: A short waiting period following RFA enhances the visibility of tumor margins and electrode tips on US, thereby increasing operator confidence in assessing ablative margin sufficiency. Implementing an immediate short waiting period may improve the accuracy of treatment.

Purpose: This study aimed to establish a novel acne scoring system (GAGS-HFUS) that combined the Global Acne Grading System (GAGS) with high-frequency ultrasound (HFUS), and to evaluate its predictive value for unfavorable treatment response in patients who have moderate-to-severe acne.

Methods: This prospective study recruited consecutive patients with mild-to-severe acne vulgaris. The GAGS-HFUS was developed based on the HFUS-detected morphological characteristics of acne and the GAGS facial region classification. Acne severity was assessed using both ultrasonic scales (the GAGS-HFUS, Sonographic Scoring System for Acne [SSSA], and Sonographic Scoring of Acne [SOS-Acne]) and a clinical scale (the Investigator Global Assessment [IGA]). Three months of followup were conducted in a subgroup of 34 patients with moderate-to-severe acne treated with oral isotretinoin. Univariate and multivariate Poisson regression analyses were conducted to determine the predictive value of GAGS-HFUS for unfavorable treatment response in this subgroup.

Results: Overall, 60 patients with mild-to-severe acne (mean age, 24 years; range, 16 to 34 years; 25 males) were enrolled. The GAGS-HFUS demonstrated substantial agreement with SOS-Acne (Spearman rank correlation coefficient [Rs], 0.864; kappa, 0.713) and IGA (Rs, 0.837; kappa, 0.660). In the follow-up cohort of 34 patients with moderate-to-severe acne, GAGS-HFUS score was identified as an independent predictor of unfavorable treatment response (risk ratio, 1.125; P=0.002). Its predictive performance (area under the receiver operating characteristic curve, 0.936; P<0.001) was superior to those of IGA and SOS-Acne.

Conclusion: GAGS-HFUS is an independent predictor of unfavorable treatment response in patients with moderate-to-severe acne, underscoring its value in the strategic management of acne.

Purpose: This study evaluates the feasibility of combining deep learning (DL) and conventional computer vision techniques to classify kidney ultrasound (US) images for the presence or absence of chronic kidney disease (CKD).

Methods: A retrospective analysis was conducted on 258 kidneys (124 normal and 134 with CKD). A DL model was trained using midsagittal US images of the right kidney and corresponding contour maps to automate measurements of parenchymal thickness and parenchyma-to-sinus ratios. These features were integrated with a convolutional neural network for classification. The ground truth was determined based on clinical CKD diagnosis and laboratory data.

Results: The combined DL and conventional feature extraction model achieved an accuracy of 82%, with a specificity of 93% and a negative predictive value of 97%. This approach outperformed models that relied solely on raw US images using DL, which achieved an accuracy of 64%. The inclusion of contour-based parenchymal measurements enhanced classification performance.

Conclusion: The integration of DL with automated feature extraction enables accurate classification of CKD using minimal user input. This proof-of-concept study highlights the potential of combining artificial intelligence-driven analysis with traditional metrics to serve as a noninvasive adjunct for CKD diagnosis and monitoring.

Purpose: This study aimed to evaluate the intra-observer agreement of ultrasound elastography according to region-of-interest (ROI) size in surgically confirmed epidermal cysts.

Methods: This retrospective study included 201 surgically confirmed epidermal cysts that underwent two consecutive strain elastography and shear wave elastography (SWE) examinations. Circular ROIs were drawn in the lesion and adjacent fat to obtain the strain ratio, shear wave (SW) velocity, and SW elasticity. Lesions were stratified by ROI diameter into <2 mm (group 1) and ≥2 mm (group 2). For each parameter, the absolute intra-observer differences, intraclass correlation coefficients (ICCs), Bland-Altman bias, 95% limits of agreement (LoAs), and correlations with the ROI-to-lesion-diameter ratio (ROI ratio) were calculated.

Results: The ICCs for SW velocity were good in group 2 and moderate in group 1, whereas the ICCs for strain ratio and SW elasticity were moderate in both groups. The mean difference in strain ratio correlated positively with the ROI ratio, but not with absolute ROI diameter, whereas mean differences in SW velocity and SW elasticity correlated negatively with both ROI diameter and ROI ratio. Group 2 demonstrated significantly smaller mean differences in SW velocity and SW elasticity than group 1 (velocity, 1.20±2.12 vs. 1.17±1.32 m/s, P=0.005; elasticity, 79.5±97.9 vs. 49.2±65.5 kPa, P=0.030). Bland-Altman analysis confirmed narrower LoAs in group 2 for all three parameters.

Conclusion: An ROI diameter ≥2 mm reduced measurement differences in SWE of epidermal cysts, whereas a large ROI ratio increased measurement variability in strain ratio, supporting technique-specific ROI optimization.

The parathyroid glands play a key role in maintaining calcium-phosphate homeostasis by secreting parathyroid hormone (PTH). Hyperparathyroidism, characterized by the inappropriate overproduction of PTH, is classified as primary, secondary, or tertiary according to its pathophysiology. Although diagnosis is principally biochemical, imaging is essential for accurately localizing hyperfunctioning glands. Precise localization allows for focused minimally invasive surgery, reduces the risk of persistent or recurrent disease, and avoids unnecessary bilateral neck exploration. Current techniques include high-resolution ultrasonography, 99mTc-sestamibi scintigraphy with single-photon emission computed tomography/computed tomography (CT), four-dimensional CT, magnetic resonance imaging, and positron emission tomography/CT with tracers such as 18F-fluorocholine. Parathyroidectomy remains the mainstay of treatment; however, recent advances in thermal ablation have expanded treatment options for patients unsuitable for surgery.

Purpose: This study aimed to evaluate the effect of breath control on the reliability of two-dimensional shear wave elastography (2D-SWE) and shear wave dispersion (SWD) measurements in pediatric patients.

Methods: This study included a retrospective cohort of 163 children and a prospective cohort of 27 children (aged 8-17 years). All participants underwent 2D-SWE and SWD under both free-breathing and breath-hold conditions between September 2021 and February 2023. The prospective cohort also underwent magnetic resonance elastography (MRE). Liver stiffness and dispersion values were compared between respiratory conditions. Inter- and intra-rater agreements were assessed, and correlations with MRE were analyzed in the prospective cohort.

Results: Liver stiffness and dispersion values were significantly higher during free-breathing compared to breath-hold (mean differences: 0.22 kPa and 0.39 m/s/kHz, respectively; both P<0.01). Breath-hold improved inter-rater agreement for 2D-SWE (intraclass correlation coefficient [ICC], 0.94 vs. 0.83; P=0.005) and SWD (ICC, 0.85 vs. 0.70; P=0.048). Intra-rater agreement for 2D-SWE (ICC, 0.88 vs. 0.88; P>0.99) and SWD (ICC, 0.70 vs. 0.74; P=0.396) remained moderate to good and did not differ significantly between conditions. The correlation between 2D-SWE and MRE was stronger under breath-hold than free-breathing (r=0.73 vs. r=0.56), although this difference was not statistically significant (P=0.299).

Conclusion: Breath-holding increases the reliability of pediatric 2D-SWE and SWD by improving inter-rater agreement and correlation with MRE. However, free-breathing also demonstrates comparable reproducibility with minimal bias, supporting its clinical feasibility for use in uncooperative pediatric patients.

Four-dimensional ultrasound (4DUS) could provide more accurate characterisation of diaphragm function than existing M-mode ultrasound approaches. Therefore, the aim of this study was to investigate the feasibility of a novel method for tracking diaphragm excursion from 4DUS data. 4DUS was acquired from 12 participants who exhibited a range of breathing patterns. A custom algorithm tracked, reconstructed, and parameterized diaphragm movement using a sphere of time-varying radius. To validate the algorithm, a randomly selected slice of the sphere was sampled and compared to visual analysis. Agreement between the visual analysis and the algorithm was characterised using a Bland-Altman analysis. A root mean squared error (RMSE) metric was also calculated to quantify the fit between the ultrasound data and the spherical parametrisation. There was good agreement between the automated algorithm and visual analysis (bias, 0.09 cm; 95% limits of agreement, -0.44 to 0.25 cm). The RMSE metric was low (0.9-1.5 mm) across the 12 participants, demonstrating that the sphere was a good fit to the measured 4DUS data. This study demonstrates the feasibility of automated tracking of diaphragmatic excursion from 4DUS data using a sphere of time-varying radius. This technique may prove useful for diagnosing and monitoring breathing dysfunction.

Ductal abnormalities, such as dilated ducts with intraductal lesions, are frequently the primary ultrasound findings prompting biopsy and resulting in the early diagnosis of breast cancer or high-risk lesions. However, the Breast Imaging Reporting and Data System (BI-RADS) ultrasound lexicon provides limited guidance on these findings, categorizing them merely as associated features. To address this limitation, this review presents a critical analysis of existing literature and proposes a new classification encompassing three distinct subtypes: dilated ducts alone, dilated ducts with intraductal echoes, and intraductal masses. Additionally, an interpretation algorithm is introduced that incorporates lesion size and suspicious ultrasound features to guide BI-RADS assessment. This structured approach aims to standardize terminology, improve diagnostic accuracy, and promote consistent management of ductal abnormalities, especially in asymptomatic women.