Occasionally a second trimester fetus will be

  • No School
  • AA 1
  • 360

This preview shows page 108 - 112 out of 360 pages.

gestational age, it is even more important to perform an abdominal scan first. Occasionally, a second trimester fetus will be visualized transabdominally, and a non-sterile pelvic exam (which would increase the risk of infection) can be avoided. Transabdominal scanning technique Probe selection Use a 3.5 MHz curvilinear transducer for the transabdominal scan. Vessels Uterus Vesico- uterine pouch Bladder Cervix Vagina Rectum Cul-de-sac Ovary Fallopian tube Ureter Figure 4.1 Normal female anatomy. Image reproduced from Gray’s Anatomy (image out of copyright). 94 Diagnostic ultrasound First trimester ultrasound
Image of page 108

Subscribe to view the full document.

Views At least two views are necessary for complete evaluation of the uterus: a transverse view and a longitudinal view, both demonstrating the endometrial stripe (and uterine contents, if any). Like the suprapubic window used in the FAST and renal exams, the transabdominal ultrasound of the patient with an early pregnancy is easier with a full urinary bladder. An inadequately filled bladder is one of the most common causes of a technically inadequate transabdominal exam. Begin by placing the probe above the pubic symphysis ( Figure 4.3A ). Start in the midline, and use both the transverse and the sagittal/longitu- dinal orientations. Again, careful angulation and movement off the midline may be necessary to obtain optimal views of the structure being evaluated (and to see the endometrial stripe). Remember that when scanning trans- versely the probe marker is to the patient’s right ( Figure 4.3B ), and Anterior Posterior Iliac vessels Rectum Cul-de-sac Ovary with follicles Fallopian tube Uterus Figure 4.2 Normal female anatomy. Note the relation between the ovaries and the iliac vessels; ovaries are found superior and medial to vessels on ultrasound imaging. Image reproduced from Gray’s Anatomy (image out of copyright). Diagnostic ultrasound 95 First trimester ultrasound
Image of page 109
POSTERIOR FORNIX (A) ANTERIOR FORNIX BLADDER LABIUM MINUS LABIUM MAJUS CLITORIS SYMPHYSIS SIGMOID COLON UTERUS S.M INT exT. SPHIN. RECTUM VAGINA DREGHT (B) (C) Figure 4.3 Probe positioning and anatomy in transabdominal scanning. ( A ) The anatomy underneath the probe; image reproduced from Gray’s Anatomy (image out of copyright). ( B ) Transverse probe position (probe marker to patient’s right). ( C ) Longitudinal probe position (probe marker to patient’s head). 96 Diagnostic ultrasound First trimester ultrasound
Image of page 110

Subscribe to view the full document.

when scanning longitudinally the probe marker is to the patient’s head ( Figure 4.3C ). When an image of the transverse uterus is identified, fanning superiorly and inferiorly in order to visualize the entire uterus in a two- dimensional sweep is essential. When a sagittal or longitudinal view of the uterus is obained it is essential to fan side to side to visualize the complete structure. Figure 4.4 shows transabdominal images of a non-pregnant female pelvis, and Figure 4.5 is a transabdominal longitudinal image of a uterus with IUP, with the bladder noted anteriorly and the uterus and rectum posteriorly. The uterovesicular pouch is anterior to the uterus, and the pouch of Douglas is posterior to the uterus.
Image of page 111
Image of page 112
  • Fall '19

What students are saying

  • Left Quote Icon

    As a current student on this bumpy collegiate pathway, I stumbled upon Course Hero, where I can find study resources for nearly all my courses, get online help from tutors 24/7, and even share my old projects, papers, and lecture notes with other students.

    Student Picture

    Kiran Temple University Fox School of Business ‘17, Course Hero Intern

  • Left Quote Icon

    I cannot even describe how much Course Hero helped me this summer. It’s truly become something I can always rely on and help me. In the end, I was not only able to survive summer classes, but I was able to thrive thanks to Course Hero.

    Student Picture

    Dana University of Pennsylvania ‘17, Course Hero Intern

  • Left Quote Icon

    The ability to access any university’s resources through Course Hero proved invaluable in my case. I was behind on Tulane coursework and actually used UCLA’s materials to help me move forward and get everything together on time.

    Student Picture

    Jill Tulane University ‘16, Course Hero Intern

Ask Expert Tutors You can ask You can ask ( soon) You can ask (will expire )
Answers in as fast as 15 minutes