What is Transcerebellar Diameter (TCD) and whats the normal measurements?

I just had a ultrasound done and I'm looking at my fetal measurements scan and I've come across Trans cerebellar Diameter (TCD) the doctors and midwifes haven't told me anything and the internet has virtually nothing on this topic either. Does anyone know what this is? and what the normal measurements for a 33 week fetus is? as mine say 46.3 mm >95%

I hope its normal!

2 Answers

  • noa
    Lv 7
    9 years ago
    Favorite Answer

    Hi Chonner,

    5 different sites i've tried, they all give info on TCD but I found them virtually impossible to transcribe back to you. It seems it's only done the odd time for research and absolutely nothing to worry about.

    Have a look at radiology.rsna.org, you may have a better understanding than I did.

    Best of luck with your new baby. x

  • 4 years ago

    TCD is the widest diameter across the cerebellar hemispheres

    Normal TCD graph :-


    (± 2SD, wks)

    12-18 wks ± 1.0 wks

    18-24 wks ± 1.8 wks

    24-30 wks ± 2.0 wks

    30-36 wks ± 2.4 wks

    36-42 wks ± 3.2 wks

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