Re: yolk sac
From: Terry J DuBose (tjdubose@juno.com)
Sun May 27 21:12:07 2001
Dr. Udayakumar, I think it might be easiest to just post it on OBGYN.net
and let anyone download.
--
Terry J DuBose.
On Sun, 27 May 2001 14:35:03 -0500 "Daniel Margulies"
<danymarg@movi.com.ar> writes:
> Dear Dr. Udayakumar
>
> I think that all of us will like that presentation
> Yhanks you in advance
>
> -----Mensaje original-----
> De: udaya kumar <udaya@md2.vsnl.net.in>
> Para: Multiple recipients of list ULTRASOUND
> <ultrasound@mail.medispecialty.com>
> Fecha: Viernes, 25 de Mayo de 2001 10:20 p.m.
> Asunto: Re: yolk sac
>
> >Dear Terry,
> >The extraamniotic space has a fluid that can been aspirated
> Coelocentesis) .
> >Using FISH probes it appears that Karyotyping is possible at 6weeks
> gestation.
> >Made a powerpoint presentation on Coelocentesis in a recent
> conference.
> Will
> >post it to you if you want it.
> >.Udayakumar
> >
> >DuboseTerryJ@uams.edu wrote:
> >
> >> According to Moore & Persaud, DEVELOPING HUMAN: Clinically
> Oriented
> >> Embryology, W. B. Saunders, 1993 p. 40-46 & 70-80; what we see
> >> sonographically is actually the "secondary yolk sac". The
> "primary yolk
> >> sac" develops earlier (during 3rd LMP week, i.e. 9 days after
> conception)
> >> and is too small to visualize sonographically. The secondary
> yolk
> develops
> >> around conceptual day 13 (start of 4 LMP week).
> >>
> >> You are correct in that the yolk is related to the formation of
> the fetal
> >> gut. Moore & Persaud has a great graphic representation of this
> process
> on
> >> page 71. The amnion forms around the embryo and separates or
> "squeezes"
> the
> >> yolk sac from the midgut and intraembryonic coelom at about 26-28
> post
> >> conception.
> >>
> >> An interesting bit of trivia... I had always wondered what the
> "choronic
> >> cavity" outside the amnionic sac contained... I was sure that it
> was not
> a
> >> vacuuume, but could not find any reference other than "cavity".
> Finally
> >> during research for FETAL SONOGRAPHY, I found the answer in:
> Benirschke
> K;
> >> "NORMAL DEVELOPMENT", Chapter 4; in Creasy RK and Resnik R,
> Editors;
> >> MATERNAL-FETAL MEDICINE: Principles and Practice, 2nd Edition; W.
> B.
> >> Saunders Company, 1989; p. 117.
> >> "As the pregnancy progresses the thin amniotic membrane enlarges
> and will
> >> contain the embryo, the yolk sac will remain outside the amnion.
> See
> Figure
> >> 16-12C. The amniotic sac with it's embryo, and the yolk sac are
> all found
> >> within the so called "gestational sac". This gestational sac is
> actually
> the
> >> chorionic cavity. The chorionic space around the amniotic sac is
> filled
> >> "...by a gel that liquefies upon touching, the magma reticulare."
> This
> magma
> >> reticulare has a slightly echogenic appearance when compared to
> the very
> >> clear amniotic fluid; see Figure 16-12C. The magma reticulare is
> also
> called
> >> the "chorioamniotic accumulation" and is a normal finding before
> the
> amnion
> >> and chorion fuse." See: DuBose, FETAL SONOGRAPHY, W. B. Saunders
> Co.,
> 1996,
> >> p. 370.
> >>
> >> Terry J. DuBose, M.S., RDMS, Assistant Professor
> >> Director, Diagnostic Medical Sonography Program
> >> CHRP, University of Arkansas for Medical Sciences
> >> Little Rock, Arkansas, USA
> >> 501-686-6510
> >> http://www.io.com/~dubose/ <http://www.io.com/~dubose/>
> >> http://www.uams.edu/CHRP/dmshome.htm
> <http://www.uams.edu/CHRP/dmshome.htm>
> >>
> >> http://www.obgyn.net/us/panel/panel.htm
> >> <http://www.obgyn.net/us/panel/panel.htm>
> >>
> >> -----Original Message-----
> >> From: Dr. N. A. Mohile [mailto:namohile@satyam.net.in]
> >> Sent: Friday, May 25, 2001 10:42 AM
> >> To: Multiple recipients of list ULTRASOUND
> >> Subject: yolk sac
> >>
> >> The round structure seen within the gestation sac by 5 weeks and
> called
> yolk
> >> sac is visible even at 12 weeks outside the amniotic
> sac.Embryologically
> >> yolk sac forms the gut.Is this structure really yolk sac?
> >> -Nila.
> >
>
