Lecture One Normal Anatomy of the Female Pelvis and Transvaginal Sonography Holdorf Outline Skeletal Ligaments Musculature True Pelvic Muscles Pelvic Organs Urinary Bladder Vagina Uterus Cervix ID: 741600
Download Presentation The PPT/PDF document "Ultrasound of the Female Pelvis" is the property of its rightful owner. Permission is granted to download and print the materials on this web site for personal, non-commercial use only, and to display it on your personal computer provided you do not modify the materials and that you retain all copyright notices contained in the materials. By downloading content from our website, you accept the terms of this agreement.
Slide1
Ultrasound of the Female Pelvis
Lecture One
Normal Anatomy of the Female Pelvis and Transvaginal Sonography
HoldorfSlide2
Outline
Skeletal
Ligaments
Musculature
True Pelvic Muscles
Pelvic Organs
Urinary Bladder
Vagina
Uterus
CervixSlide3
Layers of the UterusUterine Size
Uterine Positional Variations
Ovaries
Ovarian Size
Fallopian Tubes
Other Stuff
Peritoneal Recesses
Vascular Anatomy
Doppler Flow CharacteristicsSlide4
Transvaginal SonographySlide5
Skeletal
The word pelvis is derived from the Latin and Greek, meaning “dish” or “bowl”. The bony Pelvic girdle is the central section of the axial skeleton.
It is positioned between the lower end of the spine, which it supports, and the lower extremities, upon which it rests. Slide6
Four bones compose the bony pelvis:Sacrum
Coccyx
Two innominate bones-fusion of the ilium, ischium, and the pubis.Slide7
False pelvis sits above this plane and is bounded by the iliac wings. It is a broad shallow cavity that supports the abdominal viscera.
True pelvis sits below this plane and is further divided into the
pelvic inlet
and the
pelvic outlet.Slide8
In the absence of masses in the non-gravid patient, the uterus, ovaries, and adnexa are situated in the true pelvis.
Of interest:
The Sacrum, Coccyx, and two innominate bones.
True Pelvis and False pelvis.Slide9
Sacrum, Coccyx, and two innominate bones…Slide10Slide11
True pelvis/False PelvisSlide12
Ligaments
Pelvic ligaments can be classified as those which bind the pelvic bones together (Osseous) and those which support the uterus and ovaries (suspensory).Slide13
Osseous ligaments
Sacroiliac binds the sacrum and iliac bones
Sacrosiatic binds the sacrum, iliac and coccyx
Sacrococcygeal binds the sacrum and coccyx
Pubic binds the two pubic ramiSlide14
Suspensory Ligaments
Cardinal: arise superiorly and laterally from the uterus and inferiorly from the vagina to provide primary support for the uterus
Broad: extend from the lateral aspects of the uterus, and attach to the lateral pelvic side walls.
Sacro-uterine extends posterolaterally from the supravaginal cervix, encircle the rectum, and insert onto the fascia over the sacrum.Slide15
Suspensory Ligaments
Round: situated anterior and inferior to the broad ligaments and fallopian tubes, they attach the uterine cornu, to the anterior pelvic wall.
Ovarian: Attach the inferior ovary to the uterine cornu, posterior to the fallopian tube on each side.
Mesovarium: Attach the ovary to the posterior layer of the broad ligament on each side.
Infundibulopelvic are actually the superior margin of the broad ligament on each side, lateral to the fimbrial of the fallopian tubes, through which course the ovarian vessels and nerves.Slide16Slide17Slide18
Musculature
Most pelvic muscles are paired structures that form the limits of the pelvic space. They can be divided into the following groups:Slide19
False Pelvis Muscles (Abdomino-pelvic) Since the false pelvis sits well above the pelvic floor, few muscles are required to support the organs found within.Slide20
Rectus Abdominis forms the anterior margin of the abdominal and pelvic spaces. It extends from the symphysis pubis to the costal margin.Slide21
Psoas Major: originates at the lower thoracic vertebrae and extends lateral and anterior as it courses through the lower abdomen, along the pelvic side wall to eventually insert on the lesser trochanter. Just inferior to the iliac Crest, it merges with the iliacus muscle creating the Iliopsoas muscle. It forms part of the lateral margins of the pelvic basin.Slide22
Iliacus: arises at the iliac crest and extends inferiorly until it merges with the psoas major. It forms the iliac fossa on both of the pelvic side walls.Slide23Slide24
Broad Ligament (Ascites must be present)Slide25Slide26
Transverse Iliopsoas muscleSlide27
True Pelvic Muscles
The floor of the true pelvis consists of two layers of muscle: Those of the perineum and those deep in the pelvis.
The primary purpose of these muscles is to hold the pelvic organs in place. Muscular fibers from these muscles insert onto the walls of the rectum, vagina and urethra preventing them from being displaced during episodes of increased intraabdominal pressure.Slide28
Levator Ani and Coccygeus:
Constitute the pelvic diaphragm muscles.
The levator ani attaches to fuse with the opposite side, and thus form the floor of the pelvic cavity.
The coccygeous arise from the Ischial spine and the sacro-sciatic ligament on either side, insert onto the coccyx and close the posterior part of the pelvic diaphragm and outlet.Slide29
Levator AniSlide30Slide31
Obturator Internus is a triangular muscle arising from the anterio-lateral wall of the pelvis. It extends from the brim of the true pelvis and exits through the lesser sciatic foramen to insert on the greater trochanter of the femur.Slide32
Piriformis arises from the sacrum, pass laterally through the grater sciatic notch, and insert on the greater trochanter of the femur. They are identified posteriorly in the pelvis.Slide33
PELVIC ORGANSSlide34
Urinary Bladder
A musculomembranous, highly distensible sac located between the symphysis pubis and the vagina.
The ureters insert in the inferior third of the posterior wall on either side.
The superior concavity of the balder is called the dome.
The walls are composed of three layers of tissue: Outer epithelial, middle Muscularis, and inner mucosal.Slide35
When empty, the mucosal layer is quite thick and can be seen sonographically.
When the bladder is distended, the mucosa is stretched and can no longer be seen.
The urethra, which allows for the excretion of urine, arises along the inferior middle portion of the bladder. At its point of exit, it is surrounded by a thickened region of the bladder wall referred to as the internal urethral sphincter.Slide36
Full urinary bladder Trans abdominal imagingSlide37
Vagina
The vagina is a muscular tube, approximately 7-10 cm in length, extending from the cervix to the external vaginal introitus.
A ring-like bind pouch surrounds the cervix, known as the vaginal fornix, and is categorized as follows:Slide38
Posterior fornix: surrounds the posterior aspect of the external cervix. It is a frequent site of vaginal fluid collections due to gravity dependence.
Lateral fornix: surround the lateral aspect of the external cervix on either side.
Anterior fornix: Surrounds the anterior aspect of the external cervix. It is much smaller than the posterior fornix.Slide39
Vaginal fornicesSlide40Slide41
Uterus
The uterus is a muscular structure suspended by ligaments, and is normally located in a mid Sagittal plane in the true pelvis. It is bordered anteriorly by the urinary bladder, and posteriorly by the recto sigmoid colon.
The uterus is divided into two major portions:
The body: Is the largest part, and contains the uterine cavity. It is muscular, and widens superiorly at the fundus, above the insertion of the fallopian tubes. The cone-shaped cornua are lateral, where the tubes enter the uterus. Slide42
The lower uterine segment, sometimes called the isthmus, transitions into the cervix at the location of the internal os.Slide43
Longitudinal UterusSlide44
Transverse Uterus with IUCDSlide45
The Cervix
Located posterior to the angle of the urinary bladder, is comprised of elastic tissue.
It is narrower than the uterine body and measures 3-4 cm in length in the nulliparous female. The lower portion of the cervix projects into the vagina.Slide46
Image of the CervixSlide47
Layers of the Uterus
Mucosa (Endometrium) is the innermost lining. It consists of a superficial layer (Zona Functionalis) and a deeper basal layer. It varies in thickness in the premenopausal woman during the different stages of the menstrual cycle. Thickness varies from 1mm immediately following menstruation to up to 8mm just prior to the beginning of menstruation. The measurements are obtained sonographically in the antero-posterior (AP) Dimension. Slide48
Muscularis (Myometrium) is an extremely thick, smooth muscle layer that is continuous with that of the fallopian tubes and vagina. Slide49
Serosa (Perimetrium) is the peritoneal covering of the uterus. It adheres to the fundus and most of the body and is not visible sonographicallySlide50Slide51
Uterine Size
Age in years
Length in mm
AP in mm
2-8
33
7.5
9-menarche
43
13
Nulliparous
80
30
Multiparous
90
40
Postmenopausal
Varied based on parity
Varied based on paritySlide52
Uterine Positional Variations
Uterine position is highly variable, and changes with varying degrees of bladder and rectal distention.Slide53
Anteversion
Refers to the cervix, which is anchored at the angle of the bladder and freely movable than the corpus and fundus, forming a 90-degree angle with the vagina.Slide54
Retroversion
refers to the cervix oriented more linearly in relation to the vagina.Slide55
In the case of a flexion (or bending) between the uterine body and the cervix, the terms ANTEFLEXION and RETROFLEXTION are used to describe the orientation of the endometrial cavity
ANTEFLEXTION describes the corpus and fundus bending forward and resting over the lower uterine segment.
RETROFLEXION refers to the corpus and fundus bending to lie posterior to the cervix.Slide56
A. Anteversion-AnteflexionB. Anteversion-Retroflexion
C. Retroversion-Anteflexion
D. Retroversion-RetroflexionSlide57
Uterine PositionSlide58
Anteverted/Anteflexed
Anteverted/anteflexed is the normal uterine position when the urinary bladder is empty.
In anteflexed the fundus is bent forward and rests over the lower uterine segmentSlide59
Retroverted
A retroverted uterus is one that is tilted backwards inside of the pelvisSlide60
Retroflexed
A retroflexed uterus has the fundus tilted down toward the rectum, while the cervix remains in the normal positionSlide61
Endometrial Thickness & Sonographic Appearance
The endometrium varies in thickness and sonographic appearance according to the menstrual cycle
During the menstrual phase, the endometrium is thin and echogenic
During the proliferative phase the endometrium is a thin echogenic line that increases in thickness and measures 4-8 mm
During the periovulatory period the endometrium measures 6-10 mm
During the secretory phase the endometrium measures 7-14 mm
For postmenopausal women the endometrium measures less than 8 mmSlide62
Side-to-Side deviation
The long axis of the uterus may also deviate to either side of midline.
Unless there is pelvic pathology displacing the uterus, any of the above configurations are considered normal variants in position.Slide63
Ovaries
The ovaries are ovoid-shaped structures suspended within the pelvic peritoneal sac, posterior to the broad ligament.
Ovarian location is variable, especially in women who have been pregnant.
The parenchyma is divided into an outer functional layer (cortex) which contains a large number or primordial follicles, the source of eggs at ovulation, and the inner ovary (medulla) which is essentially blood vessels and connective tissue. Slide64
The hilum, through which channel the ovarian vessels and nerves, is situated on the anterior surface of each ovary.
Both the suspensory ligament of the ovary and fimbriae of the fallopian tube attach to the superior surface of each ovary.Slide65Slide66
Normal Ovary with Functioning CystsSlide67
Ovarian Size
Size
Volume
Premenopausal
Varies with Ovulatory stage
3.5 cm x 2.0 cm x 1.5 cm
5.1cm3 -3.2cm3
Postmenopausal
Varies with number of years since menopause
2.0 cm x 1.0 cm x .05 cm
1.3cm3Slide68
Ovarian Volume
length x width x AP (in cm) x 0.523Slide69
Fallopian Tubes
The fallopian tubes are musculomembranous tubes, approximately 7-12 cm in length, that widen as they extend from the uterine cornu laterally to the ovaries.
Intramural or interstitial region is the narrowest portion where the tube is contained within the cornu of the uterus.
Isthmus is the narrow segment of the tube adjacent to the uterine wall.Slide70
Ampulla is the longest portion. The lumen increases in diameter to terminate as the trumpet-shaped infundibulum, opening into the peritoneal cavity. Small finger-like projections called fimbria extend to capture the released ovum from the ovary.Slide71
Intramural, isthmic, ampullary and fimbria portions of the fallopian tubeSlide72
A Dilated Fallopian Tube:PyosalpinxSlide73
Other StuffSlide74
Peritoneal Recesses
Several potential spaces exist in the pelvic cavity, created by the locations of the organs and suspensory structuresSlide75
SPACE OF RETZIOUS aka prevesical or retropubic space is situated between the pubic bone and anterior urinary bladder wall. Rarely, fluid is seen in this space. Masses in this space will displace the bladder posteriorly.
VESICOUTERINE POUCH aka anterior cul-de-sac is located anterior to the lower uterus and posterior to the urinary bladder. This space is usually empty, but may contain loops of small bowel.
RECTOUTERINE SPACE aka the posterior cul-de-sac, or pouch of Douglas is located posterior to the cervix and anterior to the rectum. It is the most common location where free fluid is located.Slide76
Space of RetziusSlide77
Vesicouterine PouchSlide78
Vascular anatomy
Arterial
The internal iliac arteries dive deep into the pelvis and divide into anterior and posterior trunks. The anterior branches give rise to several arteries: obturator, umbilical, superior vesicle, inferior vesicle, uterine, vaginal, and inferior gluteal arteries.Slide79
Diagram of the uterine arteriesSlide80
Doppler flow characteristics
Uterine arteries
Moderate to high velocity/high resistance flow
Higher resistance flow in the proliferative phase than the luteal phase
Higher resistance flow in postmenopausal women than in women of reproductive ageSlide81
Ovarian Arteries
In the follicular phase, flow is often low velocity and high resistance.
In the periovulatory period and luteal phase, impedance drops dramatically on the side with the dominant follicle.
In post-menopausal women, the resistive index approaches 1.0 with increasing age.Slide82
Hint: Everything is high resistance except for the ovary that has the dominant follicle, where the resistance is low.Slide83
Doppler flow of the Dominant ovary (low resistance)Slide84
Doppler Flow of a non-dominant ovary (high resistance)Slide85
Transvaginal Sonography
Depicts anatomy within a 2 to 7cm focal range.
Cannot be inserted past the area of vaginal fornices.
Limited to visualizing the uterus and adnexa in the non-gravid patient and the lower uterine segment in a gravid patient.
Provides a more extensive view of the pelvic anatomy.Slide86
There are many applications for a transvaginal sonogram including but not limited to:
Evaluation of ectopic pregnancy
Uterine, ovarian and pelvic inflammatory disease
Placenta previa
Fetal anatomy and cardiovascular systems
Monitoring ovulationSlide87
TVS may also be used for guided procedures such as:
Ova aspiration
Embryo transfer
Drainage or aspiration of pelvic fluid
Treatment of ectopic pregnancySlide88
Transvaginal ultrasound is performed very much like a gynecologic exam and involves the insertion of the transducer into the vagina after the patient empties her bladder.
The tip of the transducer is smaller than the standard speculum used when performing a Pap test.
A protective cover is placed over the transducer, lubricated with a small amount of gel and then inserted into the vagina. Slide89
Only two to three inches of the transducer end are inserted into the vagina. The images are obtained from different orientations to get the best views of the uterus and ovaries.
Transvaginal ultrasound is usually performed with the patient lying on her back, possibly with her feet in stirrups similar to a gynecologic exam.
Slide90
How do you scan?
Transversely and sagittal. This is not something you answer on paper. You have to get your hands on a probe and just do it.Slide91
Why can’t you perform a TVU after 14 weeks gestation, but you can have intercourse?
You CAN use the TV probe after 14 weeks: to assess placenta previa, the internal cranial structures in a cephalic presentation, and the L/S spine in breech presentations.Slide92
What are the benefits of TV over transabdominal?
Higher resolution means clearer image.
Higher frequency means better resolution.
Well tolerated by most patients.Slide93
What are the risks of the TV procedure?
Patient may accurse the sonographer of assault or worse.
Latex allergy
Chemical sensitivity-irritation to the vaginal area.
Decrease sperm mobility due to the applied gel.
A miscarriage or abortion following the procedure may initiate a lawsuit against the hospital/doctor/sonographerSlide94
When was the first TVU performed?Do not know. Was used infrequently in the late 70s. Took off in the mid-late 80s.Slide95
What are the contraindications for a TV?
Patient too young
Patient too old
Patient bleeding profusely.
Virginal patient
Non-compliant patient.Slide96
How do you know if you are in Transverse of Sag?
By rotating the transducer, keeping the bladder in sight as a landmark.Slide97
Can you rupture a cyst upon probe insertion?There is always the possibility-especially if a cyst is very large (Ovarian cyst), and the probe is jabbed or pushed up against the lower cervical area. More than likely, the answer to this is no.Slide98
Can you perform Doppler with a Transvaginal probe?Yes…it is done all the time.Slide99
Can you harm a fetus with a TV probe?No. The probe cannot be inserted far enough to harm the fetus, if inserted in properly and with care. Slide100
At what age can you first perform this? (Minimum age)
In the case of precious puberty, it may be indicated quite young… But what is too young? The probe is big relatively speaking so you will not want to tear any structures. 10, 11, 12 usually is the cut off age.