Chapter 13: Pelvic Anatomy

What is the equation for ovarian volume?

(LxWxAP in cm) X 0.523

What are the 3 layers of the endometrium?

1. Basalis layer 2. Functionalis Layer 3. "Inner Ring"

What are the layers of the uterus?

1. Endometrium (muscosa) 2. Myometrium (muscularis) 3. Perimetrium (serosa)

What are the 3 layers of the cervix?

1. Internal Cervical Os 2. Cervical Canal 3. External Cervical Os

What are the 3 ovarian suspensory ligaments?

1. Mesovarium 2. Ovarian (utero-ovarian) 3. Suspensory (infundibulopelvic)

What are the layers of the urinary bladder?

1. Muscosal 2. Muscularis 3. Epithelial

What are the 4 osseous ligaments?

1. Sacroiliac 2. Sacrococcygeal 3. Sacrosciatic 4. Pubic

What are the 3 tissue layers of the Fallopian tubes?

1. Serosal outer layer 2. Muscular middle layer 3. Muscosal inner layer

What are the 3 pelvic recesses?

1. Space of retzius 2. Anterior cul-de-sac 3. Posterior cul-de-sac

What are the 5 uterine suspensory ligaments?

1. Uterosacral Ligament 2. Cardinal Ligament 3. Round Ligament 4. Pubovesicular Ligament 5. Broad Ligament

Postmenopausal Ovarian Size

2.0 X 1.0 X .5

Pediatric Ovarian size

2.5 X 1.5 X .5

Menstrual Ovarian Size

3.0 X 2.0 X 1.0

What is the normal length of uterus in an nulliparous adult?

8 cm

What is the normal length of uterus in an multiparious adult?

9 cm

What is a Graafian follicle?

Also called the dominant follicle; it is a mature follicle developed in the follicular phase of menstrual cycle

False pelvis

Area superior to and anterior to the pelvic brim

Retroverted

Backward tilted cervix w/ uterine corpus in normal position

Luteal Phase (Days 15-28)

Dominate (or Graafian) follicle curves into the Corpus Luteum - in the absence of fertilization, the corpus leteum begins to atrophy and regress

What is the landmark to find ovaries?

External iliac artery

Ovarian blood supply is from the...

Gonadal arteries

What are other names for the false pelvis?

Greater or Major pelvis

Regarding doppler - higher peaks indicate what?

Higher RI (resistivity index)

Linea Terminalis

Imaginary line drawn from the pubic crest to the arcuate line dividing the true and false pelvis

Where is the corpus lute formed?

In an ovary at the site of a follicle or sac, that has matured and released its ovum

What is the equation for ovarian size?

Length X Width X AP (in cm)

What causes uterine positional variants?

Malposition due to laxity of cervical and round ligaments

Functiaonlis Layer

Middle layer, echogenic

Anteverted/Anteflexed

Normal position of uterus

What are the pelvic ligaments?

Osseous, Ovarian Suspensory, and Uterine Suspensory

What ligaments support the ovaries?

Ovarian ligament, Suspensory ligament, Mesovarian ligament

Ovarian outflow

Ovarian venous plexus -> ovarian vein -> internal iliac vein

In the vagina, where is the frequent site for collection of vaginal fluids?

Posterior Fornix

What is included in the skeletal anatomy?

Sacrum, Ilium, Pubic Ramus, Pubic Symphysis, Ischium, and Coccyx

How do you measure uterine size?

Serosa of the fundus to the external cervical os

What is the pelvic anatomy?

Skeletal, Ligamentous, Muscular, Urinary Bladder, Uterus, and Ovaries

T/F: A postmenopausal uterus has normal cervical contour

True

T/F: An adequately full bladder for scanning is distended above the fundus of the uterus.

True

T/F: Fallopian tubes lie within the broad ligament

True

T/F: A pediatric uterus has relatively larger cervical length and width

True - b/c of mothers hormones

What is in the muscular anatomy?

True pelvis & False pelvis

Uterine outflow

Uterine venous plexus -> uterine vein -> internal iliac vein

What is the normal length of uterus postmenopausal adult?

Varied based on parity

What is another name for the anterior cul-de-sac?

Vesicouterine recess

Broad Ligament

a double fold of peritoneum containing fat, vessels, and nerves; divides the true pelvis into anterior and posterior

Corpus Luteum

a hormone-secreting structure that develops in an ovary after an ovum has been discharged but degenerates after a few days unless pregnancy has begun

Multiparous

a woman who has borne more than one child

Nulliparous

a woman who has never given birth

Where do the gonadal arteries arise from?

abdominal aorta

The false pelvis is _______ the true pelvis.

above

Post Menopause

after the cession of menstruation

Uterosacral Ligament

anchors the cervix; secures the uterus to the sacrum

Pubovesicular Ligament

anchors the inferior portion of the bladder to the bony pelvis

Round Ligament

anchors the uterine fundus to the anterior pelvic wall (creating the common uterine anteflexion)

What does it mean if a uterus is "version"

angulation of cervix

What does it mean if a uterus is "flexion"

angulation of uterine corpus

Retroflexed

backward-tilted uterine corpus with cervix in normal positions

Where is the urinary bladder located?

between the symphysis and vagina

What do the osseous ligaments do?

bind skeletal structures together

Follicular Phase (Days 1-14)

both ovaries develop follicles, resulting in the development of a single, mature Graafian follicle under the influence of FSH (Follicle stimulating hormone)

Retroverted/Retroflexed

both uterus and cervix are tilted backward

Pelvic outlet

bounded by ischial tuberosities and coccyx (with True pelvis)

Pelvic Inlet

bounded by pubic rami and sacral promontory (with False pelvis)

The false pelvis mostly contains...

bowel

Uterine blood supply if from...

branches of the internal iliac arteries that ascend along the lateral walls of the uterus from the cervix

Vagina

fibromuscular tube extending from external cervical os to external vaginal introitus; attaches to the cervix to form the anterior, posterior, and lateral vaginal fornices

Why do you want to scan someone with a full bladder distending above the fundus?

for visibility of the fundus - bladder is the acoustic window

"Inner Ring"

hypoechoic

Infundibulum

inner, funnel - shaped cavity of the ampullary portion

Endometrium

innermost lining of the uterine cavity; varies in thickness during the menstrual cycle

The true pelvis mostly contains....

internal organs of reproduction

Body of Uterus

largest portion of uterus; it contains the uterine cavity and narrows inferiorly at the isthmus

What is another name for the true pelvis?

lessor or minor pelvis

Isthmic

longest portion of the Fallopian tube, connecting the intramural and ampullary portion

Cervix

more fibrous/less muscular portion of uterus; neck of uterus

Fallopian Tubes

musculomembranous tubes extending laterally from each uterine cornu to the corresponding ovary

Interstitial

narrowest portion of the fallopian tube, which traverses the cornu of the uterus

Basalis Layer

outer layer; hypoechoic

Ovaries

paired structures lying posterior to the broad ligament; comprised of an outer cortex & inner medulla

Perimetrium

peritoneal outer layer

True Pelvis

portion of the pelvic cavity inferior and posterior to the pelvic brim

What are other names from the pouch of Douglas?

posterior cul-de-sac or rectouterine recess

Pouch of Douglas

potential space between the rectum and uterus

Anterior cul-de-sac

potential space between the uterus and urinary bladder

What are pelvic recesses?

potential spaces formed by draping of peritoneum over the uterus

What is another name for the space of retzius?

properitoneal space

Skeletal Anatomy

provides structural support and protection for pelvic organs; serves as a weight bearing bridge between the spine and lower extremities; directs detail head during childbirth

Fundus

rounded, superior portion of uterus above insertion of fallopian tubes

Ovulation (Day 14)

rupture of the mature follicle and release of (ovum) egg in anticipation of fertilization

What do the fallopian tubes do?

serve to transport ova from the paraovarian space to the uterine cavity

Fimbriae

small finger-like projections found at the ampullary portion of the Fallopian tube surrounding the ovary and capture the released ovum following ovulation

Space of Retzius

space between the pubic symphysis and urinary bladder

Adnexa

structures closely related structurally and functionally to the uterus such as the ovaries, fallopian tubes, or any of the surrounding connective tissue

What do the uterine suspensory ligaments do?

support and suspend uterus and cervix to pelvic cavity

What does the ovarian suspensory ligaments do?

suspend ovaries and Fallopian tubes in the pelvis cavity

Menarche

the first occurrence or onset of menstruation

Gravida

the number of times that a woman has been pregnant regardless of the outcome

Parity

the number of times that a woman has given birth to a fetus with a gestational age of 24 weeks or more, regardless of outcome

Cardinal Ligament

the primary supporting ligament of the uterus

Menstruation

the process in a woman of discharging blood and other materials from the lining of the uterus at intervals of about one lunar month from puberty until menopause; expect for pregnancy

Myometrium

thick, muscular layer that is continuous with the Fallopian tubes and vagina

Isthmus or Lower Uterine Segment (LUS)

transitional segment between body and cervix

What is another name for a translabial exam?

transperineal ultrasound

Ampulla

trumpet shaped, open portion of the Fallopian tube adjacent to the ovary

Where does fertilization occur?

within the ampulla portion of the Fallopian tubes

What is normal length of cervix in an adult?

~3 cm