May 12, 2023 · The T sign is really the absence of a twin peak sign (or lambda (λ) sign) and is used in ultrasound assessment of a multifetal pregnancy. It refers to the lack of chorion extending between the layers of the intertwin membrane , denoting a monochorionic pregnancy .

Jun 12, 2019 · T sign: Indicates monochorionic twins, with thin membrane and absence of thickening at membrane insertion site ; Note: A single placental mass does not rule out dichorionic twins ; Lambda or Delta Sign Indicating Dichorionic Twins

Jan 15, 2025 · Ultrasound assessment of chorionicity, fetal biometry, anatomy, Doppler velocimetry and amniotic fluid volume is used to identify and monitor twin pregnancies at risk of adverse outcomes, such as twin-to-twin transfusion syndrome (TTTS) and FGR.

Absence of "twin peak" sign neither excludes dichorionic pregnancy nor implies monochorionicity. Seen in over 50% of dichorionic twins, especially in the first trimester (10-14 weeks is optimal). It may disappear by week 20 in 7% of dichorionic pregnancies with fused placentas (therefore absence after wk 20 should be viewed with caution) (4).

Nov 18, 2015 · Ultrasound assessment of fetal biometry, anatomy, Doppler velocimetry and amniotic fluid volume is used to identify and monitor twin pregnancies at risk of adverse outcomes such as twin-to-twin transfusion syndrome (TTTS) and fetal growth restriction (FGR).

The presence of a chorionic peak or the ‘lambda sign’ (Figure 1 (a)) usually indicates a dichorionic pregnancy in comparison to the ‘T sign’ (Figure 1 (b)) that is associated with a monochorionic pregnancy.

Monochorionic diamniotic (MCDA) twins are only separated by the two thin layers of the amnion which is said to give the appearance of a “T” and is known as the “T-sign” and is less than 2 millimeters thick [2,4].

Twin Pregnancy: T Sign and Lambda Sign. From the POCUS Bytes Webinar, Ultrasound Gold Standard for Evaluating Placenta and Twin Pregnancy with Rawan Alsukairi, RDMS.

Jun 11, 2024 · If ultrasound reveals a single placental mass without the presence of a lambda sign, twins can be designated as monochorionic. In this case, a thinner membrane with a "T" sign may be visible, indicating two amniotic sacs (monochorionic diamniotic).

The "T sign" is really the absence of a twin-peak sign (or lambda (λ) sign) and is used in ultrasound assessment of a multifetal pregnancy. It refers to the lack of chorion extending between the layers of the intertwin membrane , denoting a monochorionic pregnancy .