Abstract
This is essential reading for those involved in combined screening; a paper stating clearly that you can have the best technique in the world for obtaining NT measurements but certain machine–transducer combinations will mean your values may vary by several tenths of a millimetre. For example, a known 2.0 mm target may measure anything from 1.8 mm to 2.2 mm. Such differences are clinically significant. Oh and the authors remind us that most machines are not calibrated to tenths of millimetres anyway.
Things are changing with the management of symptomatic liver haemangiomas. This review confirms that surgery is not always the answer. Troublesome ones that are painful, bleed or cause pressure effects may be eligible for radiofrequency ablation, arterial embolization, radiotherapy or chemotherapy.
Two investigators achieved very good agreement using 2D and 3D ultrasound on evaluating type and volume of carotid plaque involving 30 patients. They suggest 3D ultrasound may be a useful tool for risk assessment of plaque.
I’ve reported in this column before that new applications for ultrasound appear to be endless. Here’s a single-centre study that bucks the trend. Based on data collected over a 14-year period, this team suggests that spinal ultrasound as a screening tool for neonates with anorectal malformations is very poor compared to MRI (US sensitivity 15% versus MRI sensitivity 100%).
Here’s an investigation into the natural history of renal angiomyolipomas (AMLs) but note this study is not about handling those rare hyperechoic RCCs masquerading as AMLs. It seems that small isolated AMLs don’t require surveillance but multiple AMLs, or those larger than 20 mm, or those associated with genetic conditions are more likely to grow and therefore warrant follow-up.
This study tried to find links between specific congenital abnormalities and birth order. It seems some birth defects like cardiac abnormalities and cleft lip occur more frequently in infants born to mothers of high parity (e.g. fourth, fifth, or sixth born, etc.) while other defects like spina bifida and oesophageal atresia occur more commonly in first born children. Other neural tube defects and talipes showed a U-shaped distribution affecting both first born and high order children similarly. The authors suggest we might bear this in mind when using ultrasound. Right.
I like the title and important message in this study from the University of California. Like most of us, these researchers are aware that the teaching of ultrasound is done increasingly by non-imaging specialists so they developed and piloted a radiology-led programme for 154 medical students. As with all the best courses, the students found it enjoyable as well as useful.
This article is a good contemporary overview of twin-to-twin transfusion syndrome, which many obstetric ultrasound practitioners may find interesting.
From a population of 423 pregnant women, this group measured their placentae and developed normative ‘Estimated Placental Volume’ growth curves. They found that placentae with volumes below the 10th or above the 90th centile tended to be associated with small or large newborns. There’s a long way to go, and I’m not an advocate for extra work, but perhaps these charts may help identify at-risk fetuses in the future.
This North American study looked at thermal index settings on NT images submitted by 77 practitioners seeking accreditation. They found that 20% exceeded the recommended safety levels. It would be interesting to see results from a similar study in the UK since, in my opinion, thermal index and mechanical index displays can be rather neglected.
This retrospective large-scale study of nearly 10,000 ultrasound examinations on twin pregnancies has generated customised growth charts for both dichorionic and monochorionic twins. The researchers found that ultrasound demonstrated a small but significant growth reduction in twin pregnancies compared to singletons, particularly after 30 weeks, and particularly in monochorionic twins.