NUCHAL TRANSLUCENCY
Nuchal Translucency Certification guide
Step 1:
Register with the fetal medicine foundation and complete the FMF 11-13 week certification course.
Visit:
Step 2: Apply to the MMS Labs
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Apply to the MMS Labs to perform nuchal translucency (NT) measurements for Multiple filling out an NT sonographer application form.​
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Collect 15 nuchal translucency (NT) and 15 crown-rump length (CRL) measurements and complete the NT table found on the application form. You must obtain these measurements yourself.
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Submit the completed application form to the lab, ensuring that your FMF UK NT certificate of attendance has been included.​
Multiple Marker Screening (MMS) is done by 3 provincial laboratories: Trillium Health Partners - Credit Valley Hospital, Mount Sinai Hospital and North York General Hospital.
Protocol for measurement
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The gestational period must be 11 to 13 weeks and six days.
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The fetal crown-rump length should be between 45 and 84mm.
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The magnification of the image should be such that the fetal head and thorax occupy the whole screen.
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A mid-sagittal view of the face should be obtained. This is defined by the presence of the echogenic tip of the nose and rectangular shape of the palate anteriorly, the translucent diencephalon in the centre and the nuchal membrane posteriorly. Minor deviations from the exact midline plane would cause non-visualization of the tip of the nose and visibility of the maxilla.
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The fetus should be in a neutral position, with the head in line with the spine. When the fetal neck is hyperextended the measurement can be falsely increased and when the neck is flexed, the measurement can be falsely decreased.
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Care must be taken to distinguish between fetal skin and amnion.
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The widest part of translucency must always be measured.
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Measurements should be taken with the inner border of the horizontal line of the callipers placed ON the line that defines the nuchal translucency thickness - the crossbar of the calliper should be such that it is hardly visible as it merges with the white line of the border, not in the nuchal fluid.
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In magnifying the image (pre or post freeze zoom) it is important to turn the gain down. This avoids the mistake of placing the calliper on the fuzzy edge of the line which causes an underestimate of the nuchal measurement.
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During the scan more than one measurement must be taken and the maximum one that meets all the above criteria should be recorded in the database.
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The umbilical cord may be round the fetal neck in about 5% of cases and this finding may produce a falsely increased NT. In such cases, the measurements of NT above and below the cord are different and, in the calculation of risk, it is more appropriate to use the average of the two measurements
Step 3:
Review of application
The Ontario MMS labs will review your application and assess your data point submission. If your 15 data points generate an acceptable NT performance distribution, your application is accepted and your name is added to the roster of Ontario NT registered sonographers. The Ontario MMS lab will provide you with an Ontario NT ID number (usually the same as your FMF UK ID number) and a BORN login and password. You will get two emails to the address indicated on your “new sonographer” registration form. One will contain your BORN login and the other will contain your BORN password.
If your 15 data points are not acceptable, the Ontario MMS lab will request another set of 15 data points and/or will provide you with further direction on how to proceed.
Visit:https://www.prenatalscreeningontario.ca/for-sonographers/registration-process/
​Please note that this information is exclusively for sonographers in Ontario Canada.