Re: Yolk sac number in multiple gestations (monochorionic)
From: Latha Natarajan (nattu@bgl.vsnl.net.in)
Sun Jun 27 05:04:00 2004
Could this be a case of conjoined twins with 2 y.sacs ?
LN.
> ----- Original Message -----
From: "Wolfgang Moroder, M.D." <wolfgang.moroder@tin.it>
To: "Multiple recipients of list ULTRASOUND" <ultrasound@dns.obgyn.net>
Sent: Friday, June 25, 2004 1:41 AM
Subject: Re: Yolk sac number in multiple gestations (monochorionic)
> Dear Colleagues:
>
> I have been puzzled a lot by early sonoembryologic features. In the
> case presented by Rich Dempsey I should like to post the following
> comments:
> 1) I doubt that a cystic structure of 9 mm with absent heart pulsation,
> in a gestational sac of 5 weeks is compatible with an intact early
> pregnancy,
> 2) as shown in the following case that I published on OBGYN.net
> http://www.obgyn.net/us/gallery/OB_1_Normal_Monoamniotic_Twins.jpg
>
http://www.obgyn.net/us/gallery/OB_1_Normal_Monoamniotic_Twins_Yolk_Sacs.jpg
> I have seen two early monoamniotic pregnancies with a yolk sac for each
> twin embryo, therefore even monoamniotic multiple pregnancies are
> associated with multiple yolk sacs,
> 3) early embryonic failure is often characterized by a disproportioned
> growth of the amniotic sac compared to the embryonic size, even if the
> embryo is still alive as you can observe in this videoclip:
>
> http://fetalmedicine.tripod.com/test.avi (allow the 1,1 MB avi clip to
> be downloaded).
> In this case you can observe a double cystic structure of different
> size, the major cyst being 8 mm. in diameter. A pulsating embryonic
> pole can be observed between them. It is difficult to distinguish in
> this case an overgrown amniotic sac from an oversized yolk sac. This
> was an early pregnancy failure. Please let us know the F/U and, why
> not, send us a picture.
> I'd welcome lots of comments.
> Wolfgang Moroder
>
> At Wed, 23 Jun 2004, Rich Dempsey RDMS/RVT wrote:
> >
> >While EV scanning with a student, an early IUP (5.1 wks by GSD) was
> >seen- a single gestational sac containing 3 cystic structures; the
> >largest of which was 9mm. The question arose: ? In a single
gestational
> >sac (presumably a monochorionic gestation) is it possible to have 3
yolk
> >sacs, or can this be a combination of a yolk sac, vitelline membrane
> >plus possibly an early amniotic membrane. ? No embyronic pole was seen
> >(yet), no bHCG was available, however LMP and GSD placed this probable
> >early IUP at 5 weeks.
> >
> >Please forgive my hazy ignorance of embryology (and spelling).
>
> --
> Wolfgang Moroder, MD
> Prenatal Unit
> Bolzano General Hospital Italy
