Detection of Subchondral Bone Microcirculatory Perfusion in Adults with Early Osteonecrosis of the Femoral Head Using Contrast-Enhanced Ultrasound: A Prospective Study

Clinical evaluation of blood flow in femoral head necrosis using color doppler ultrasound

This study aims to utilize Color Doppler Ultrasound to collect blood flow parameters of the medial circumflex femoral artery and explore the changes in blood flow in osteonecrosis of the femoral head, providing objective indicators for clinical assessment and prognosis. Color Doppler Ultrasound was used to examine the medial circumflex femoral artery in 30 patients with osteonecrosis of the femoral head (52 hips: ARCO Stage I-2 hips, Stage II-24 hips, Stage III-24 hips, Stage IV-2 hips) and 30 healthy controls (57 hips). Arterial diameter and blood flow parameters [peak systolic velocity, resistance index, pulsatility index] were collected and analyzed for vascular and blood flow characteristics in osteonecrosis of the femoral head. (1) Compared with the healthy group, the osteonecrosis group showed significantly lower peak systolic velocity and resistance index, while no significant differences were observed in arterial diameter and pulsatility index. (2) Arterial diameter in Stage I was significantly larger than in Stages II, III, and IV, with no significant differences observed among Stages II, III, and IV. Peak systolic velocity, resistance index, and pulsatility index all significantly decreased with disease progression from Stage I to Stage IV, but no significant difference in pulsatility index was found between Stages II and III. (3) There was no significant difference in arterial diameter between the non-collapsed and collapsed groups; however, peak systolic velocity, resistance index, and pulsatility index were all significantly lower in the collapsed group compared to the non-collapsed group. (1) The alterations in blood supply in femoral head necrosis primarily manifest as changes in blood flow parameters. (2) Vascular morphology and blood flow parameters could potentially be useful indicators for assessing the progression of femoral head necrosis. (3) Changes in blood flow parameters may provide valuable insights into the risk of femoral head collapse.

The value of quantitative contrast-enhanced ultrasonography analysis in evaluating central retinal artery microcirculation in patients with diabetes mellitus: comparison with colour Doppler imaging

AIM

To compare the efficacy of quantitative contrast-enhanced ultrasonography (CEUS) analysis and colour Doppler ultrasound (CDU) in evaluating central retinal artery (CRA) microcirculation in patients with diabetes mellitus (DM).

MATERIALS AND METHODS

In this prospective study, a total of 55 patients (98 eyes) with DM were enrolled as the study group. They were compared to 46 age-matched healthy volunteers (92 eyes) who were selected as the control group. Each patient underwent CDU and subsequent CEUS examination. CDU and quantitative CEUS parameters were evaluated. The diagnostic efficiency of the diagnostic performance of CEUS and CDU was evaluated and compared, and the scale thresholds of predictive indicators for the diagnosis of proliferative diabetic retinopathy (PDR) were evaluated using receiver operating characteristics (ROC) curve analyses.

RESULTS

Group pairwise comparisons showed that the end diastolic velocity (EDV) and arrival time (AT) of CRA were significant predictors for PDR by CDU and by quantitative CEUS analysis, respectively (all p<0.05). The ROC curve analysis showed that the area under the curve value of AT was significantly higher than that of EDV (0.875 versus 0.634, p=0.0002). Accordingly, an AT cut-off value of 1.07 seconds resulted a sensitivity of 90.62 % and a specificity of 79.31 %.

CONCLUSION

Quantitative CEUS analysis can improve the accuracy of clinical staging of diabetic retinopathy for the patients with DM, and the AT showed the best diagnostic efficiency.

Application of B-flow imaging and its enhanced mode in perforator mapping

AIM

To explore the value of B-flow (B-mode blood flow) imaging and its enhanced mode in perforator mapping.

MATERIALS AND METHODS

Before surgery, B-flow imaging, enhanced B-flow imaging, colour Doppler flow imaging (CDFI), and contrast-enhanced ultrasound (CEUS) were used to detect the skin-perforating vessels and small vessels in the fat layer of the donor site. Taking the intra-operative results as the reference standard, the diagnostic consistency and efficiency of the four modes were compared. Statistical analysis was performed using the Friedman M-test, Cochran's Q-test, and the Z-test.

RESULTS

Thirty flaps were excised, with 34 skin-perforating vessels and 25 non-skin-perforating vessels, as confirmed during surgery. In order of the number of skin-perforating vessels detected, the results showed that enhanced B-flow imaging detected more vessels than B-flow imaging and CDFI (all p<0.05), CEUS detected more vessels than B-flow imaging and CDFI (all p<0.05), B-flow imaging detected more vessels than CDFI (p<0.05). All four modes had remarkable and satisfactory diagnostic consistency and effectiveness, but B-flow imaging was the best (sensitivity 100%, specificity 92%, Youden index 0.92). In order of the number of small vessels in the fat layer detected, the results showed that enhanced B-flow imaging detected more vessels than CEUS, B-flow imaging, and CDFI (all p<0.05). CEUS detected more vessels than B-flow imaging and CDFI (all p<0.05).

CONCLUSION

B-flow imaging is an alternative method for perforator mapping. Enhanced B-flow imaging can reveal the microcirculation of flaps.