The Welsh study of mothers and babies: protocol for a population-based cohort study to investigate the clinical significance of defined ultrasound findings of uncertain significance.

BACKGROUND: Improvement in ultrasound imaging has led to the identification of subtle non-structural markers during the 18 - 20 week fetal anomaly scan, such as echogenic bowel, mild cerebral ventriculomegaly, renal pelvicalyceal dilatation, and nuchal thickening. These markers are estimated to occur in between 0.6% and 4.3% of pregnancies. Their clinical significance, for pregnancy outcomes or childhood morbidity, is largely unknown. The aim of this study is to estimate the prevalence of seven markers in the general obstetric population and establish a cohort of children for longer terms follow-up to assess the clinical significance of these markers. METHODS/DESIGN: All women receiving antenatal care within six of seven Welsh Health Boards who had an 18 to 20 week ultrasound scan in Welsh NHS Trusts between July 2008 and March 2011 were eligible for inclusion. Data were collected on seven markers (echogenic bowel, cerebral ventriculomegaly, renal pelvicalyceal dilatation, nuchal thickening, cardiac echogenic foci, choroid plexus cysts, and short femur) at the time of 18 - 20 week fetal anomaly scan. Ultrasound records were linked to routinely collected data on pregnancy outcomes (work completed during 2012 and 2013). Images were stored and reviewed by an expert panel.The prevalence of each marker (reported and validated) will be estimated. A projected sample size of 23,000 will allow the prevalence of each marker to be estimated with the following precision: a marker with 0.50% prevalence to within 0.10%; a marker with 1.00% prevalence to within 0.13%; and a marker with 4.50% prevalence to within 0.27%. The relative risk of major congenital abnormalities, stillbirths, pre-term birth and small for gestational age, given the presence of a validated marker, will be reported. DISCUSSION: This is a large, prospective study designed to estimate the prevalence of markers in a population-based cohort of pregnant women and to investigate associations with adverse pregnancy outcomes. The study will also establish a cohort of children that can be followed-up to explore associations between specific markers and longer-term health and social outcomes.

Accuracy of sonographic vascular features in differentiating different causes of cervical lymphadenopathy.

This study was undertaken to evaluate the accuracy of the power Doppler sonographic features in differentiating cervical lymphadenopathy in different diseases. We reviewed power Doppler sonograms of 270 patients with palpable neck nodes (metastases n = 101, lymphoma n = 21, tuberculosis n = 76, reactive n = 72). Confirmed diagnosis was either made by fine-needle aspiration cytology on the largest node or by excision biopsy. In each patient, the largest node was included in the study. The node was evaluated using the vascular pattern, displacement of vascularity and vascular resistance (resistance index, RI, and pulsatility index, PI). Individual groups were compared and the optimum vascular feature in the differential diagnosis was determined. Vascular pattern was more useful in differentiating reactive nodes from malignant nodes, with a sensitivity of 88% for metastases and 67% for lymphoma, and a specificity of 100%. RI with a cut-off value of 0.8 was more accurate in distinguishing metastases (RI > 0.8) from lymphoma (RI < 0.8), with an accuracy of 65% and 75%, respectively. Displacement of vascularity was helpful to differentiate tuberculous nodes (accuracy: 67%) from reactive and lymphomatous nodes (accuracy: 100% and 95%, respectively), whereas PI with a cut-off of 1.5 helped the differentiation between tuberculosis (PI < 1.5) and metastases (PI > 1.5), with an accuracy of 77% in both diseases. When appropriate criteria are used, power Doppler sonography is a valuable adjunct in the sonographic evaluation of cervical lymphadenopathy.