Ch. 5 normal anatomy of the female pelvis
What are the four most common uterine positions?
1. Anteflexed 2. Anteverted 3. Retroflexed 4. Retroverted
The pelvic diaphragm consists of what muscles?
1. Coccygeus muscle 2. Levator Ani group
What are the 5 pelvic organs?
1. External genitalia 2. Unitary bladder and urethra 3. Uterus, Fallopian tubes, and vagina 4. The ovaries 5. The colon and rectum
What does the cortex of the ovaries consist of
1. Follicles in various stages of development 2. Tunica albuginea
What are the four segments of the uterus?
1. Fundus 2. Body or corpus 3. Isthmus 4. Cervix
What are the three key descriptions of pelvic muscle appearance on US
1. Hypoechoic compared to fat or smooth muscle 2. Linear internal echos that show the muscle fiber bundles 3. Echogenic fascia and retroperitoneal fat outline the boarders
What are the four portions of the Fallopian tubes?
1. Interstitial/intramural 2. Isthmus 3. Ampulla 4. Infundibulum
What 3 things make ultrasound one of the most popular imaging modalities?
1. Non ionizing radiation 2. There are two approaches 3. High resolution images
What are the three layers of the bladder, and which layer is not visible on sonography?
1. Outer layer: serosa layer. NOT VISIBLE ON SONOGRAPHY due to thinness and intimate contact with adjacent layers of fascia and fatty tissue 2. Middle layer: muscularis or detrusor muscle. Thick layer with smooth muscle fibers 3. Inner layer: mucosa. VERY echogenic
What 3 tissue layers make up the uterus?
1. Perimetrium 2. Myometrium 3. Endometrium
What are the 3 principle functions of the female pelvis?
1. Provides weight bearing bridge between the spine and the lower limbs 2. Directs the pathway of the fetal head during childbirth 3. Protects reproductive and other pelvic organs
Postmenopausal normal mean ovarian volume
5.8cm^3
Premenopausal Volume of an Ovary
6-9cm^3
Describe the vaginal canal?
7-10 cm or smooth muscle
Average length of the Fallopian tubes
7-14 cm (don't usually see on a US)
Hypoechoic
Appears darker on US
adnexa
Area around an organ
orthogonal
At right angles (perpendicular)
Anteflexion
Bending of the fundus toward the abdominal wall
retroflexed uterus
Bending of the fundus toward the rectum
What is the frequency range for endovagional transducers?
Between 5 and 9 MHz
Where is the urinary bladder located?
Between the symphysis pubis and the vagina
B
Bladder
What is the only ligament seen with ultrasound? And under what conditions can it be seen in?
Broad ligament BUT is only seen when ascites is present
What is the normal sonographic appearance of an ovary?
CHOCOLATE CHIP COOKIES Smooth despite follicles Homogenous echotexture May exhibit small more echogenic medulla Small anechoic or cyclic follicles may be seen in the Cortex
Which ligament connects the cervix to the lateral pelvic wall?
Cardinal ligament
What does the central medulla layer of an ovary consist of?
Connective tissue containing blood, nerves, and lymphatic vessels
What are the two layers of the ovary?
Cortex- outer layer Medulla- inner layer
Cervix
Cylindrical projection into the vagina that secretes an alkaline secretion that helps with sperm penetration Acts as a sphincter during pregnancy Usually around 3cm
Describe a newborn uterus
Different ratio than normal adult proportions: 2/3 cervix and 1/3 body and fundus. The cervix is larger than the body and fundus
Fimbriae function
Direct the ovum into the Fallopian tube following ovulation
What is the main function of the broad ligament?
Divides the true pelvis into anterior and posterior compartments
What are the pros for EVS sonography?
EVS (endovaginal) techniques allow higher frequency transducers, thus increasing the detail because of the close proximity to pelvic organs.
ascites
Excessive free fluid
Which "pelvis" supports the intestines?
False pelvis
What provides optimal imaging for the transabdominal exam?
Filled urinary bladder AND Curvilinear broadband transducer in the 3-5 MHz range
infundibulum
Fimbrae at the end that maintain close relationship with the opening of the tube and the ovary
How do you calculate a cervical measurement?
Finding the measurement from the internal Os to the External Os
Follicle
Fluid filled structure of an ovary which an egg develops before ovulation
Ante
Forward
What frequency setting does transvaginal imaging use?
High frequency transducer
Follicle-stimulating hormone (FSH)
Hormone that stimulates growth and maturation of the ovarian Graafian follicle. The anterior pituitary gland secretes the hormone
How will the deeper, permanent basal layer of the endometrium of the uterus appear sonographically?
Hyperechoic and will remain thin
How do skeletal muscles appear on an ultrasound?
Hypoechoic compared to fat or smooth muscle Exhibits linear internal echos outlining the muscle bundles (looks like striations on a muscle)
What pelvic muscles occupy the false pelvis?
Iliacus
What muscles make up the levator ani group?
Iliococcygeus Pubococcygeus Puborectalis
Where is endometriosis usually located?
In the ovaries
hypertrophy
Increase in size
What are the characteristics of a low frequency setting?
Increased depth, decreased resolution
What are the characteristics of a high frequency transducer?
Increased resolution, decreased depth
What part of the uterus marks the transition between the body and the cervix of the uterus?
Isthmus
Describe Fallopian tube width
It widens as it moves away from the uterus
LA
Levator Ani muscles
What is the location of the piriformis muscle?
Located deeply posterior in the true pelvis LESS ROUTINELY IMAGED DUE TO ITS DEEP LOCATION
Interstitial/intramural
Located within the uterine wall or within the Cornu Lumen is approx. 1mm MOST NARROW PORTION OF THE FALLOPIAN TUBE
What frequency setting is used with transabdominal pelvic imaging?
Lower frequency settings
Ampulla
Lumen approx. 6mm, the widest of the Fallopian tube. Curves around the ovary Normal site of Fertilization
Calculation for volume of an ovary
LxWxH/2= volume in cm^3
Isthmus
Medial portion Closest to the uterus
What ligament attaches the ovary to the posterior layer of the broad ligament?
Mesovarian ligament (like a part of the broad ligament)
What pelvic muscles occupy the true pelvis?
Obturator internus Piriformis Coccygeus Levator ani
OI
Obturator internus muscle
Which muscle can be easily mistaken for ovaries on US?
Obturatur internus muscle
Internal Os
Opening from the cervix into the uterus
External Os
Opening from the cervix into the vagina
Which ligament can you use to sometimes help you find the ovaries?
Ovarian ligament aka utero-ovarian ligament
What are the four uterine layers from outer to inner?
Papa Mama Baby Fetus Perimetrium Myometrium Basilis layer of the endometrium and Functionalis layer of the endometrium
What are fornices?
Portion of the vagina around the cervix that creates gutters
What ligament do the ovaries attach to?
Posterior aspect of the broad ligament
What is the most common site for pelvic fluid to collect?
Posterior cul-de-sac
What space lies between the uterus and the rectum?
Posterior curl-de-sac AKA pouch of Douglass
What is an alternate filling method to achieve a full bladder?
Preexisting Foley catheter
What three muscles form the iliopsoas muscle?
Psoas major Psoas minor iliacus
Describe an adult uterus ratio
Ratio: 1/3 cervix and 2/3 body and fundus
R
Rectum
Which muscle forms most of the anterior body wall?
Rectus abdominus
What pelvic muscles occupy the abdomnopelvic region?
Rectus abdominus Psoas major
What is one of the most common complaints of pain during pregnancy?
Round ligament pain
What 4 bones form the osseous pelvis?
Sacrum Coccyx Two large innominate bones (fusion of ilium, is hum, and pubic bones)
What scan plane is best to use to determine muscle?
Sagittal
What space lies between the pubic symphysis and the bladder?
Space of Retzuis AKA retropublic or previssicle space
What is the benefit of TAS sonography?
TAS (transabdominal) scanning uses LOWER frequency settings which results in GREATER depth of an atomic coverage
What is the space that lies between the uterus and the bladder?
The anterior cul-de-sac AKA vesicouterine space
What is the uterine Cornu?
The area where the uterus starts to form into the fallopian tubes
Which layer of the uterus will remain constant though the menstrual cycle and which layer of the uterus will change through the menstrual cycle?
The basal layer of the endometrium will remain constant and the functionalis layer of the endometrium will change as it sheds through the menstrual cycle
Body or corpus of the uterus
The main portion of the uterus
Which fornix is a frequent site of vaginal fluid build up?
The posterior fornix BECAUSE OF GRAVITY. the pt. Lies down, fluid builds in the posterior fornix
Which fornix is bigger, the posterior fornix or the anterior fornix?
The posterior fornix. the anterior fornix is smaller than the posterior fornix. (think: the posterior fornix has to be big enough to catch all that fluid!)
What muscle does the psoas major muscle merge with, and what muscle does this merge create?
The psoas major merges with the iliacus muscle which forms the iliopsoas muscle
Homogenous
The same
What is the con to TAS sonography?
The use of lower frequency results in decrease a atomic resolution
How many fornices are there and what are they called? THINK IN 3D WITH THIS
There are 4 fornices 1. Anterior fornix - surrounds the anterior aspect of the external cervix 2. Posterior fornix- surrounds the posterior aspect of the external fornix 3. Lateral fornix 1- surround the lateral aspect of the external fornix on either side 4. Lateral fornix 2- surround the lateral aspect of the external fornix on either side
anteversion
Tipping of the entire uterus toward the anterior abdominal wall. USUAL POSITION OF THE UTERUS WHEN THE BLADDER IS EMPTY
Retroverted uterus
Tipping of the entire uterus toward the sacrum
What is the purpose of the uterosacral ligament?
To provide posterior support to the uterus. Attaches posterior uterus to anterior sacrum
What is the purpose of the cardinal ligament?
To provide support to the uterus and cervix on either side
Isthmus
Transition from the corpus to the cervix
What is the function of Fallopian tubes?
Transport fertilized ovum to the uterus through peristaltic contractions
What "pelvis" can both the coccygeus and the levator ani muscles be found in?
True pelvis
What tissue covers the cortex of the ovary
Tunica Albuginea- a dense connective tissue
What are the outer arteries of the Uterus?
U Are Really Smart Uterine, Arcuate, Radial, Spiral
fundus of the uterus
Upper expanded portion of the uterus between the Fallopian tubes. Round or domed shaped
U
Uterus
What is considered abnormal volume of an ovary
Volume of more than TWICE that of the OPPOSITE side is considered abnormal regular doses of actual size
When is the bladder considered adequately full for sonography?
When the dome of the bladder extends above the uterine fundus
multiparous
a woman who has given birth two or more times
Retro
backward
nulliparous
female who has borne no offspring
What is the imaginary line that separates the true and false pelvis?
linea terminalis
Contralateral
opposite side
What bones form the posterior wall of the pelvis?
sacrum and coccyx
Ipsilateral
same side