Journal of Medical Ultrasonics最新文献

Purpose: Knee osteoarthritis (OA) is symptomatic, especially in terms of motion during activities of daily living. The infrapatellar fat pad (IFP) has a buffering function, owing to morphological changes within the knee joint, whereas poor morphological change in the anterior space of the IFP is often observed in symptomatic knee OA. This study aimed to investigate the correlation between morphological changes in the anterior space of the IFP during walking and symptoms in patients with knee OA.

Methods: Twenty-six patients with knee OA (OA group) and 11 healthy volunteers (control group) participated in this study. Ultrasonography revealed the IFP thickness in the anterior space during static and dynamic evaluations in the supine and walking positions. The waveform of the IFP during walking was constructed with a continuance value of the IFP in video mode. Moreover, it identified the difference in IFP between maximum and minimum values on the waveform as morphological change in IFP (ΔIFP). A three-dimensional motion analysis system was used to calculate the kinetics and kinematics of walking. The OA group underwent clinical evaluation using the Knee Injury and Osteoarthritis Outcome Score (KOOS).

Results: ΔIFP in the OA group was smaller than that in the control group, whereas there was no significant difference in supine IFP thickness. Moreover, there was a significant positive correlation between ΔIFP and KOOS-pain in the knee OA group, but not in terms of other parameters of IFP, kinetics, and kinematics.

Conclusions: Patients with symptomatic knee OA exhibit restricted morphological change in IFP during walking.

Purpose: Extranodal extension (ENE) of metastatic carcinoma in patients with papillary thyroid carcinoma (PTC) has been associated with an increased risk of recurrent disease, persistent disease, and disease-specific mortality; however, ultrasound findings suggestive of ENE have not been well established. In this study, we aimed to identify ultrasound findings suggestive of microscopic ENE and validate them histologically.

Methods: We retrospectively examined the ultrasound and histological findings of 21 PTC patients with microscopic ENE and 46 without ENE.

Results: Node matting, irregular shapes, ill-defined jagged border, and perinodal hyperechoic rims were observed in 38.1%, 57.1%, 42.9%, and 57.1% of lymph nodes with ENE, respectively, and the frequencies were significantly higher than those without ENE, with p values less than 0.05, 0.0005, 0.0001, and 0.0001, respectively. The sensitivity and specificity of cases with any one of irregular shapes, ill-defined jagged border, and perinodal hyperechoic rims were 81.0% and 82.6%, respectively. Histologically, node matting, irregular shape, ill-defined jagged border, and a perinodal hyperechoic rim correspond to adhesion between lymph nodes, extensive invasion, minimal invasion, and invasion into adipose tissue, respectively.

Conclusions: We would argue that any irregular shape, ill-defined jagged border, and perinodal hyperechoic rim can be accepted as findings indicative of microscopic ENE.

Purpose: Accurate identification of lumbar vertebral levels is crucial for the success of various interventional procedures, but conventional fluoroscopic guidance exposes both patients and physician to radiation. While ultrasound has emerged as a potential radiation-free alternative, its accuracy in elderly patients with spinal deformities remains unclear.

Methods: In this single-center cross-sectional study, we compared ultrasound-guided versus palpation-guided lumbar level identification in 115 patients scheduled for lumbar surgery between July 2019 and January 2020. Patients were randomly assigned to ultrasound guidance (U group, n = 57) or conventional palpation (P group, n = 58). The primary outcome measure was accuracy of vertebral level identification, verified by intraoperative fluoroscopy.

Results: The U group demonstrated significantly higher accuracy (82.5%) compared to the P group (50.0%) (p = 0.0003, 95% CI [1.5-4.4]). Accuracy was particularly high at the L4 level (U group: 90.3%, P group: 55.9%, p = 0.0023). After adjusting for age and planned needle insertion site, ultrasound guidance maintained superior accuracy (OR = 5.5, 95% CI: 2.3-14.0, p = 0.0002).

Conclusions: Ultrasound guidance provides superior accuracy in lumbar level identification compared to conventional palpation, even in elderly patients with spinal deformities. This technique may offer a reliable, radiation-free alternative, potentially reducing radiation exposure while maintaining high accuracy.

Purpose: The detection rate of congenital morphological abnormalities during ultrasound examinations in early pregnancy is not sufficient with B-mode alone due to the small size of the target. This study aimed to evaluate the effectiveness of routine color Doppler mode compared to B-mode alone in the early detection of congenital heart disease (CHD) during first-trimester screening.

Methods: A before-after clinical study was conducted at Showa University Hospital between January 2012 and May 2023. In April 2018, the protocol was modified to incorporate routine color Doppler mode. We compared detection rates, specificity, positive predictive values (PPV), and negative predictive values (NPV) between the B-mode only group and the B-mode with routine color Doppler group.

Results: Among the 12,321 fetuses screened, 5,907 were screened with B-mode only and 6,414 with routine color Doppler mode. The detection rate for CHD was significantly higher with color Doppler mode (29.26% vs. 64.15% for all CHDs, p < 0.001; 48% vs. 85.71% for major CHDs, p = 0.001) without impairing the specificity (99.96% vs. 99.98%) or PPV (94.44% vs. 92.31%).

Conclusion: Routine use of color Doppler mode in first-trimester CHD screening significantly increases detection rates while maintaining high specificity and PPV. This protocol supports early CHD diagnosis, facilitating timely prenatal counseling and management.

Purpose: To evaluate the technical feasibility and performance of automatic image-based registration (IBR) for liver fusion imaging and to identify clinical and anatomical factors affecting registration success.

Materials and methods: This prospective study included 84 patients undergoing liver fusion imaging using an ultrasound system with IBR. Three operators with 5, 10, and 25 years of experience (junior, intermediate, and senior), respectively, independently performed IBR. Fusion time and registration error were recorded. Fusion success was defined both globally (success by all or at least one operator) and individually (registration error < 10 mm). Clinical and anatomical factors were assessed. Predictors of failure were identified using multivariable logistic regression with Firth's correction.

Results: IBR was successful in all three operators in 86.9% of cases and by at least one operator in 96.4%. The most experienced operator achieved significantly shorter fusion times (median: 15.0 s) and smaller fusion errors (median: 6.0 mm) compared to the less experienced operators. Operator-specific success rates defined as registration error < 10 mm were 45.2%, 60.7%, and 79.8%, respectively (p < 0.001). Subcutaneous tissue depth was the only independent predictor of fusion failure in both multivariable models (OR = 1.13 for all failed, p = 0.033; OR = 0.88 for partial success, p = 0.012). Other clinical factors were not statistically significant.

Conclusion: IBR is a highly feasible method that reduces operator dependency in liver fusion imaging compared to conventional methods, though registration accuracy still varies with operator experience.

Clinical impact: IBR enables consistent and simplified fusion imaging regardless of operator experience. Its broad applicability may support safer and more efficient ultrasound-guided interventions, especially in resource-limited or time-sensitive settings.

Purpose: To compare the performance of attenuation coefficient (AC) and sound speed (SS) for evaluating liver steatosis in participants who underwent liver fat quantification using magnetic resonance imaging (MRI)-derived proton density fat fraction (PDFF).

Methods: Participants with chronic liver disease who underwent both MRI-PDFF (reference standard) and multiparametric ultrasound (US) measurements (such as for AC and SS) were retrospectively enrolled. The associations between the clinical variables and US markers were determined using multivariate linear regression. The diagnostic performance of US markers for detecting steatosis grades was evaluated using the area under the receiver operating characteristic curve (AUC).

Results: Fifty-three participants were included. Patients with metabolic dysfunction-associated steatotic liver disease were predominant (34 out of 53, 53.2%). Multivariate regression analysis revealed significant associations of AC with PDFF (regression coefficient: 0.05, p = 0.003) and body mass index (regression coefficient: 0.0094, p = 0.01). SS was also significantly associated with PDFF (regression coefficient: -12.20, P = 0.03) and body mass index (regression coefficient: -3.08, p = 0.01). The AUCs for AC and SS were 0.88 (95% CI: 0.79-0.97) and 0.70 (95% CI: 0.55-0.84), respectively, for identifying participants with steatosis grade S1 or higher. The performance of detecting steatosis grade S1 or higher was improved and more balanced when AC was ≥0.54 dB/cm/MHz and SS was ≤1536 m/s; the sensitivity and specificity were 72% and 86%, respectively.

Conclusion: SS was associated with PDFF and demonstrated fair diagnostic performance in identifying steatosis grade S1 or higher. The combined use of AC and SS may improve the detection of hepatic steatosis.