Standardization of diagnosis for coiling of the umbilical cord around fetal neck by ultrasound.

OBJECTIVE: To elucidate classification of coiling of the umbilical cord around fetal neck (CUFN) by ultrasound and forming factors of entanglement angle of CUFN. METHODS: From January 2006 to December 2012, color Doppler ultrasonic was used to observe the blood flow vector of umbilical artery, and prospective descriptive observation was made for entanglement direction and type of 707 single fetuses taking prenatal examination in our hospital during the middle and late trimester of pregnancy and having umbilical cord echo around the neck. The relationship of position of fetus, position of placenta and entanglement direction of umbilical cord with the entanglement angle of umbilical cord is analyzed. RESULTS: Among the 707 fetuses, 634 had one circle of coiling, 43 had two circles of coiling, two had three circles of coiling, and 28 had CUFN. According to entanglement direction, 361 had entanglement from left to right and 318 had entanglement from right to left According to entanglement type, 305 were C-shaped type (43.14%), 85 were O-shaped type (12.02%), 289 were α-shaped type (40.88%), and 28 were L-shaped type (3.96%). CONCLUSION: Color Doppler ultrasound was used to detect the entanglement direction of umbilical cord and establish the five-type classification of umbilical cord around the neck, laying the foundation for the feasibility of establishing the normalization of diagnostic standard of umbilical cord around the neck.

Acoustic radiation force impulse imaging for non-invasive assessment of renal histopathology in chronic kidney disease.

OBJECTIVE: To investigate the stiffness values obtained by acoustic radiation force impulse (ARFI) quantification in assessing renal histological fibrosis of chronic kidney disease (CKD). METHODS: 163 patients with CKD and 32 healthy volunteers were enrolled between June 2013 and April 2014. ARFI quantification, given as shear wave velocity (SWV), was performed to measure renal parenchyma stiffness. Diagnostic performance of ARFI imaging and conventional ultrasound (US) were compared with histologic scores at renal biopsy. Intra- and inter-observer reliability of SWV measurement was analyzed. RESULTS: In CKD patients, SWV measurements correlated significantly with pathological parameters (r = -0.422--0.511, P<0.001), serum creatinine (r = -0.503, P<0.001), and glomerular filtration rate (r = 0.587, P<0.001). The mean SWV in kidneys with severely impaired (histologic score: ≥19 points) was significant lower than that mildly impaired (histologic score: ≤9 points), moderately impaired (histologic score: 10-18 points), and control groups (all P<0.001). Receiver operating characteristic (ROC) curves analyses indicated that the area under the ROC curve for the diagnosis of renal histological fibrosis using ARFI imaging was superior to these conventional US parameters. Using the optimal cut-off value of 2.65 m/s for the diagnosis of mildly impaired kidneys, 2.50 m/s for moderately impaired kidneys, and 2.33 m/s for severely impaired kidneys, the corresponding area under the ROC curves were 0.735, 0.744, and 0.895, respectively. Intra- and intre-observer agreement of SWV measurements were 0.709 (95% CI: 0.390-0.859, P<0.001) and 0.627 (95% CI: 0.233-0.818, P = 0.004), respectively. CONCLUSIONS: ARFI may be an effective tool for evaluating renal histological fibrosis in CKD patients.