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Publications (2)4.37 Total impact

  • Article: Evaluation of cervical stiffness during pregnancy using semiquantitative ultrasound elastography.
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    ABSTRACT: Objective. To evaluate cervical stiffness during pregnancy using ultrasound-derived elastography, a method used to estimate the average tissue displacement (strain) on a defined region of interest when oscillatory compression is applied. Methods. Strain was calculated in two regions of interest, the endocervical canal and the entire cervix, from three anatomical planes of the cervix: mid-sagittal in the plane used for cervical length measurement, and in cross-sectional planes located at the internal and external cervical os. Associations between strain values, method of ascertainment and patient characteristics were assessed using linear mixed models to account for within-subject correlation. Inter-rater agreement in defining the degree of cervical stiffness was evaluated in 120 regions of interest acquired by two operators in 20 patients. Results. A total of 1557 strain estimations were performed in 262 patients at 8-40 weeks of gestation. Adjusting for other sources of variation, 1) cervical tissue strain estimates obtained in the endocervical canal were on average 33% greater than those obtained in the entire cervix; 2) measures obtained in the cross-sectional plane of the external cervical os and sagittal plane were 45% and 13% greater compared to those measured in the cross-sectional plane of the internal cervical os, respectively; 3) mean strain rate was 14% and 5% greater among multiparous women with and without a history of preterm delivery compared to nulliparous women, respectively, and was on average 13% greater among women with a cervical length between 25-30mm compared to those with a cervical length >30mm; and 4) cervical tissue strain was more strongly associated with cervical length than with gestational age. Conclusion. Semiquantitative elastography can be employed to evaluate changes in cervical stiffness during pregnancy. Copyright © 2012 ISUOG. Published by John Wiley & Sons, Ltd.
    Ultrasound in Obstetrics and Gynecology 11/2012; · 3.01 Impact Factor
  • Article: Transabdominal evaluation of uterine cervical length during pregnancy fails to identify a substantial number of women with a short cervix.
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    ABSTRACT: To assess the diagnostic performance of transabdominal sonographic measurement of cervical length in identifying patients with a short cervix. Cervical length was measured in 220 pregnant women using transabdominal and transvaginal ultrasound (US). Reproducibility and agreement between and within both methods were assessed. The diagnostic accuracy of transabdominal US for identifying cases with a cervical length <25 mm was evaluated. Twenty-one out of 220 cases (9.5%) had a cervical length <25 mm by transvaginal US. Only 43% (n = 9) of patients with a short cervix were correctly identified by transabdominal US. In patients with a cervical length of <25 mm by transvaginal US, transabdominal measurement of the cervix overestimated this parameter by an average of 8 mm (95% LOAs, -26.4 to 10.5 mm). Among women without a short cervix, transabdominal US underestimated cervical length on average (LOA) by 1.1 mm (95% LOAs, -11.0 to 13.2 mm). Transvaginal US was also more reproducible (intraclass correlation coefficient: (ICC) (0.96; 95% CI, 0.94 to 0.97) based on comparisons between 2D images and immediately acquired 3D volume datasets relative to transabdominal US (ICC: 0.71; 95% CI, 0.57 to 0.84). Transvaginal US detected 13 cases with funneling and six cases with sludge whereas only three cases of funneling and one of sludge were detected by transabdominal US. Transabdominal measurement overestimated cervical LOA by 8 mm among women with a short cervix and resulted in the underdiagnosis of 57% of cases.
    The journal of maternal-fetal & neonatal medicine: the official journal of the European Association of Perinatal Medicine, the Federation of Asia and Oceania Perinatal Societies, the International Society of Perinatal Obstetricians 01/2012; 25(9):1682-9. · 1.36 Impact Factor