The 11-14 Week Scan
This presentation will cover the combined nuchal translucency test and the 11-14 week anomaly scan.
When doing the 11-14 week scan, we endeavour to pick up abnormalities as early as possible. What must be highlighted is that not all abnormalities may be diagnosed at the 11-14 week scan. There are obvious technical difficulties relating to fetal size, dates, development, position and patient size. However if we can diagnose an abnormality early, this may have advantages with patient management.
The best technique for an 11-14 week scan will use both TA and TV scans. TA is best for fetal orientation, situs, most nuchal lucencies and general overview. It may be better than TV for high positioned fetuses.
TV is best for cervix, adnexae, ovaries, uterus, placenta, most fetal anatomy and some nuchal lucencies.
A cervical canal < 25 mm has been associated with onset of premature labour.
Placenta, liquor, retroplacental, retro chorionic regions should be imaged and scrutinized carefully.
The presentation focuses on technique, highlighting the importance of initial acknowledgement of fetal presentation and situs. Expected appearances for fetal anatomy at certain stages of pregnancy are discussed.
Many images and video clips of normal and fetal anomalies are shown.
In conclusion, the 1st Trimester Anomaly scan can be used to give an early diagnosis for many conditions, hence early patient management. However the patient must be made aware that it doesn’t currently replace the 20 week scan for many defects. We must always endeavour to do the highest quality scan possible.