Is there a use for ultrasound in the detection and characterisation of CSDs?
By Sarah Leslie, University of Derby
Aim
The Caesarean section rate is rising worldwide and with the complications associated with a Caesarean scar
defect (CSD), means a subsequent pregnancy can be high risk for these women. The aim of this review is to
determine if there is evidence to support the use of ultrasound detection and characterisation of CSDs.
Methods
A small scale literature review was carried out to establish the current evidence base for the performance of
ultrasound in identifying CSDs. A systematic search of medical databases to identify the most relevant, up to
date published material. The results were scrutinised to make sure they would inform the discussion and after
applying inclusion/exclusion criteria, narrowed to a final seven papers.
Results
The review showed that ultrasound was the first line imaging tool to assess a CSD and that the length, depth,
width, residual myometrial thickness (RMT) and anterior myometrial thickness (AMT) are the ultrasound
measurements that should be taken to assess a CSD. This will aid the gynaecologist in their decision of how to
manage the complication as there are no current management guidelines. A thin RMT and AMT, with increased
length, depth and width measurements, characterise a CSD. An RMT of 2cm and a scar depth of 0.5cm are the
cut off values to define a large CSD, with a highly significant relationship (p<0.0001) demonstrated between
large CSDs and prolonged menstruation. CSD detection rates in symptomatic women were reported at 80.9%
(p<0.05).
Conclusion
TVUS can detect CSDs in both pregnant and non-pregnant women, however with the serious complications
associated with a defect, it is of benefit to be aware before a subsequent pregnancy, to reduce the risk of CSP.
It is vital that CSD awareness is raised amongst sonographers and gynaecologists, and that they know how to
assess and report them.