TVS Endometriosis

1. Transvaginal US of Endometriosis:
Looking Beyond the Endometrioma with a
Dedicated Protocol
Belinda G Collins, MD, PhD1; Anita Ankola, MD2; Sparsh Gola, MD1; Kathryn L. McGillen, MD1
1- Department of Radiology, Penn State Health Milton S. Hershey Medical Center,
Pennsylvania State College of Medicine, Hershey, Pa
2- Department of Radiology, University of Florida College of Medicine, Jacksonville, Fla

2. For this journal-based SA-CME activity, the authors, editor, and reviewers have
disclosed no relevant relationships.
Neither the authors nor their immediate family members have a financial
relationship with a commercial organization that may have a direct or indirect
interest in the content of this presentation.
Radiologists, sonographers, gynecology practitioners, and anyone interested in
learning how to use transvaginal sonography (TVS) for the evaluation of endometriosis.
No Disclosures
Target Audience

3. Educational Goals
• Review of published TVS protocol for optimized evaluation of
endometriosis, developed by the International Deep Endometriosis Analysis
(IDEA) Consensus Group
• Discussion of the unique features of US that aid in making medical and
surgical management decisions
• Review of characteristic features of endometriosis seen at pelvic US
• Review of anatomic locations and compartments where endometriosis can
be located
• Case-based review of the varied TVS appearances and manifestations of
endometriosis within the pelvis

4. Endometriosis: Background Information (1–8)
• Presence of ectopic endometrial glands outside of the uterine cavity
• Common gynecologic condition resulting in life-altering morbidity
• Affects 3%-15% of females of reproductive age
• Exact prevalence is difficult to know owing to variable clinical manifestations
• Higher prevalence in symptomatic patients
• 50% of those with infertility
• 50%-90% of those with chronic pelvic pain
• Common symptoms include dyspareunia, dysmenorrhea, infertility, and chronic pelvic
pain
• Surgery is the reference standard for diagnosis; however:
• Surgical findings may lead to an underestimated degree of disease.
• Lesion depth is difficult to assess.
• Lesions may be obscured owing to their location.

5. Endometriosis: A Complex Disease Process
• Involves multiple locations and a wide spectrum of disease
• Varied US appearances & manifestations:
• Ovary
• Uterus
• Superficial endometriosis: nodules or plaques along the
peritoneum, without organ or retroperitoneal invasion
• Deep infiltrating endometriosis (DIE): >5-mm depth into
peritoneum, invasion of organ or retroperitoneum
• Other: pelvic adhesions, pouch of Douglas (POD) obliteration,
kissing ovaries, hydrosalpinx
• US is often the initial imaging modality for evaluation
Endometrioma
Adenomyosis

6. • It is an extension of the physical examination, with dynamic assessment.
• It can be used to assess site-specific tenderness (SST) by means of probe
palpation.
• Provocative maneuvers can be performed to assess organ mobility.
• This modality is readily accessible and inexpensive, and no intravenous
contrast material is used.
US Has Unique Beneficial Features:
But Routine Pelvic US Is Inadequate:
• Standard routine protocols are focused mainly on the uterus and ovaries.
• US is operator dependent, and imagers routinely see what they know to look for
and where to look for it.
• The use of inadequate protocols results in detection inconsistencies and
decreased sensitivity, so a dedicated endometriosis protocol is needed.

7. Dedicated Protocol for Endometriosis Is Needed
• Such a protocol takes advantage of the unique features of US.
• Such a protocol enables accurate mapping of disease extent, which is essential
information needed for treatment strategies.
• In terms of medical therapy: There is a recent increased trend toward using hormone control
to avoid surgery.
• In terms of surgical planning:
• Preoperative information of disease location and extent can be used to determine the
level of complexity and need for surgical specialists.
• Preoperative information can lead to complete resection of disease, which, in turn,
decreases the need for repeat procedures secondary to incomplete initial surgery.

8. IDEA Group (4)
• Consensus opinion is used to standardize US examinations.
• Standardized examinations lead to improved detection of the entire spectrum
of endometriosis-related disease.
• Goals:
Improve detection and assessment
Standardize result reporting, including that for:
Terminology of anatomic locations
Uniform measurement practices
Improve clinical care and research
• Consensus examination protocol has four components

9. TVS Protocol for Endometriosis (4)
1) Routine evaluation of uterus and adnexa:
• Uterus: configuration, adenomyosis?
• Ovaries: location, number, and size of endometriomas?
• Adnexa: hydrosalpinx, hematosalpinx?
2) Dedicated search of anterior and posterior compartments for DIE
3) Assessment of the sliding sign:
• Assessment of vesicouterine and rectouterine pouch obliteration
4) Detection of sonographic soft markers:
• SST
• Ovarian mobility
• Loculated fluid

10. Component 1: Evaluation of Uterus (9-12)
• Sagittal and axial US is performed to assess for adenomyosis.
• Study results have shown an association between adenomyosis and
endometriosis:
• The presence of adenomyosis correlates with more severe symptoms and a
higher stage of disease.
• Fifty percent of patients with DIE have adenomyosis.
• Symptoms
• Menorrhagia
• Dysmenorrhea

11. Evaluation of Uterus
Pseudowidening of the endometrium with indistinct margins
Multiple myometrial cysts
Multiple hyperechoic nodules with hypoechoic rims, adjacent to the endometrium
Uterine adenomyosis: Ectopic endometrial glands and stroma within the myometrium, with
or without cysts, resulting in adjacent smooth muscle hyperplasia

12. Evaluation of Uterus: Adenomyosis
US features
• Abnormal myometrial echogenicity
• Hypoechoic, isoechoic, or hyperechoic
• Heterogeneous myometrium
• Focal or diffuse
• Myometrial cysts
• Echogenic nodules or linear
striations
• Pseudowidening and poor definition
of endometrium
• Relative absence of mass effect
• Poor definition of borders

13. Component 1: Evaluation of Ovary (13-16)
• TVS is performed to assess for endometrioma(s).
• An endometrioma is considered to be a marker for the severity of
disease.
• Frequently associated with other findings
• Up to 50% of patients with DIE have an associated endometrioma, and in this
group the DIE is more multifocal and more severe and there is more adhesion
formation.
• Symptoms
• Chronic pelvic pain
• Dysmenorrhea
• Dyspareunia
• Infertility

14. Evaluation of Ovary
The appearance of DIE is identical to that
of classic ovarian endometrioma.
TRUE or FALSE?
Typical US features of an ovarian endometrioma:
• Unilocular cyst
• Homogeneous low-level echoes (ground
glass)
• No solid component
• No internal vascularity
• Perceptible wall with or without bright
reflectors
FALSE: While DIE may look similar and is avascular, it is often more hypoechoic and can have an
infiltrative nodular appearance.
SAG RT = sagittal right, TRV = transverse

15. Ovary: Endometrioma (ie, “Chocolate Cyst”)
• Cyst that forms when ectopic
endometrial glands in the ovary bleed
• Contains blood products
• Has a fibrous capsule surrounded by
ovarian parenchyma
• Bilateral in 50% of cases
• Atypical US features:
•Fluid-fluid level
•Avascular internal nodule and/or
papillary projection
•Decidualization during pregnancy can
mimic malignancy with solid
vascular components

16. Evaluation of ovary in a 28-year-old woman with long-standing right
lower quadrant pain
Endometrioma with atypical features of fluid/fluid level and avascular “nodule”

17. Evaluation of the adnexa in a 32-year-old woman with severe lower
pelvic pain and endometriosis seen at subsequent laparoscopy (17,18)
Pelvic adhesions result in dilated
fluid-filled fallopian tubes
(hydrosalpinx).
On axial view, the tubes have a
“cogwheel” appearance
secondary to the salpingeal folds.
When dilated fallopian tubes
contain blood (hematosalpinx),
there is a fluid-fluid level with
dependent hyperechoic blood
products.
Hematosalpinx is considered to
be an indicator of endometriosis.

18. Which of the following anatomic areas can have DIE involvement?
A. Bladder & ureter.
B. Bowel.
C. Uterosacral ligaments (USLs).
D. Vagina and rectovaginal septum (RVS).
E. All of the above.
Discussion begins next.

19. Component 2: Search for DIE nodules
Perform systematic
search of two main pelvic
compartments:
• Anterior
• Place probe in anterior
vaginal fornix.
• Posterior
• Place probe in posterior
vaginal fornix.
• Nodules are more
common in the
posterior compartment.
POSTERIOR
Peritoneum
ANTERIOR
Level of inferior peritoneal reflection

20. Anterior Compartment (4)
• Bladder should contain some urine
1. Trigone
 Contains orifices of urethra &
ureters
 Within 3 cm of urethral
opening
2. Base
 Anterior to vagina & cervix
 Extraperitoneal
3. Dome
 Most commonly involved
 Intra-abdominal
• Evaluate ureters from orifice to
proximal visible extent.
• Obtain survey views of kidneys to
rule out occult hydronephrosis.

21. Peritoneum
Posterior Compartment (4)
• Rectovaginal area
• Vagina
• RVS
• Posterior vaginal fornix
• Bowel
• Lower anterior rectum
Below level of peritoneal
reflection; not seen at
laparoscopy
• Upper anterior rectum
• Rectosigmoid
At level of uterine fundus
• Anterior sigmoid
Above level of uterine fundus
Level of inferior peritoneal reflection
• USLs (not shown)
• Better visualized when outlined by small volume of fluid
• Endometriosis can result in (nodular or linear) thickening
• Divides upper from lower rectum
Line along the inferior posterior lip of cervix

22. Search for DIE nodules
Endometriosis nodule with well-circumscribed smooth borders adjacent to the
right ovary, which contains a classic endometrioma
Endometrioma in ovary
BEWARE of SEARCH SATISFACTION!

23. DIE Nodule: General Facts (3,4,7,8)
• US features
• Hypoechoic
• Linear or round nodules
• Smooth or irregular borders
• Avascular to slight vascularity
• Obtain and report measurements in three
orthogonal planes
• Use standardized terminology
• Location, shape, size
• Found in 15%-30% of endometriosis cases
• Strongly associated with more substantial
symptoms
• Typically involves fibromuscular structures
• USL, bowel, vagina, bladder
• USL is most common location (69% of DIE
nodules detected at laparoscopy)

24. Search anterior compartment in a 48-year-old woman with pelvic
pain, infertility, and history of endometriosis
2.5 x 2.5 x 1.6cm
Bladder DIE nodule involving
wall of bladder dome projects
into bladder lumen, adjacent
to the fundus of the uterus
U
Bladder DIE

25. DIE: Bladder (19,20)
• Epidemiology of urinary tract DIE
• 0.3%-12.0% of women with
endometriosis
• 14%-20% of women with DIE
• Symptoms
• Frequency
• Urgency
• Dysuria
• Hematuria
Yellow line = bladder trigone, pink line = bladder base,
red line = bladder dome, white line = extraperitoneal
portion of the bladder, purple line = peritoneal
reflection. C = cervix, U = uterus, V = vagina.
Most common sites of urinary involvement: bladder in 85% of cases, ureter in 9%
of cases, kidney in 4% of cases, urethra (Ur) in 2% of cases

26. Search posterior compartment in a 35-year-old woman with irregular
bleeding, increasing pelvic pain, and a history of endometriosis.
Focal hypoechoic nodular thickening of the muscularis propria of the rectal wall, posterior to the cervix
(C and CVX). SAG = sagittal.
Bowel DIE
C

27. DIE: Bowel (3,4,7,10,21,22)
• Endometrial glands and stroma invade the hypoechoic
muscularis propia layer of bowel wall, at least, inducing
smooth muscle hyperplasia and fibrosis.
• Substantially affects patient management and is critical for
surgical planning
• Epidemiology
• Involved in 5%-12% of women with endometriosis
• Involved in 10% of women with DIE
• Most commonly (in 70%-93% of cases) affects anterior rectum &
rectosigmoid junction
• Is frequently multiple, with a second intestinal lesion present in
55% of rectal DIE cases
• Symptoms
• Diarrhea
• Rectal pain and/or bleeding
Normal hypoechoic muscularis propria
Thickened muscularis propria with tail

28. DIE: Bowel (3,4,7,10,21,22)
Normal hypoechoic muscularis propria
Thickened muscularis propria with tail
• US features
• Thickened hypoechoic muscularis propia
• Hypoechoic nodules with or without hyperechoic foci
• With or without blurred margins
• Typical shapes
• Smooth round nodule
• Nodule with tapered extension “tail” (ie, “comet”
sign)
• Nodule with spikes and fanlike projections into bowel
(ie, “Indian headdress” sign)

29. Search posterior compartment in a 41-year-old woman with increasing
pelvic pressure and dysuria several years after hysterectomy
Hypoechoic thickening of lower anterior rectum with irregular spikes
and extension into the RVS and vaginal wall
RVS DIE

30. DIE: Rectovaginal Area (3,4,23)
• Epidemiology:
• Difficult to quantify
• Reflects a severe stage of disease and is
often associated with disease elsewhere
• Sonographic DIE classification according to
location:
• RVS
• Confinement to RVS is rare
• Typically involves vagina, rectum, or both
• Vaginal fornix
• “Hourglass” lesion extends to rectum,
immediately beneath peritoneal reflection
• Symptoms
• Dysmenorrhea
• Dyspareunia
• Postcoital bleeding

31. Posterior compartment in a 46-year-old woman with chronic bilateral
lower pelvic pain and cramping, with a history of stage IV
endometriosis
Multicentric bowel involvement
Hypoechoic nodules (pink outline) with tail extension
Hourglass lesion of
posterior vaginal fornix
extending into
lower anterior rectum
-Lesion is hypoechoic,
with an irregular shape &
spikes (resembling an
Indian headdress)
Kinked and retracted bowel
Focal tenderness was elicited
when scanning the sites of
detected lesions
ROV = right ovary

32. Initial imaging revealed an atypical right
intraovarian endometrioma with a fluid-fluid
level and avascular nodule; dedicated
imaging for endometriosis was performed
subsequently.
Posterior compartment in a 28-year-old woman who presented
with right lower quadrant pain.
Additional imaging
revealed a
round hypoechoic
smooth nodule at the
torus uterinus.
USL DIE

33. DIE: USL (4,21,24,25)
• USLs extend from posterolateral portion of cervix,
encircle rectum, and insert onto sacral vertebrae.
• The torus uterinus is the junction of the right and left
USLs in the midline posterior to the cervix.
• At US, the USLs are hyperechoic. Disease results in
hypoechoic nodular or linear thickening (pink outline).
• Epidemiology
• Involved in 28%-45% of patients with endometriosis
• Most common location of DIE (69% of DIE deposits detected
at laparoscopy)
• Symptom
• Dyspareunia

34. Static images from a routine pelvic ultrasound are
sufficient to assess for pelvic obliteration.
TRUE or FALSE?
FALSE
Requires dynamic images. Discussion begins next.
Component 3: Sliding Sign Assessment (4,22,26)
• The sliding sign maneuver is an assessment of the mobility of structures, performed
by demonstrating the normal sliding of one structure relative to another:
• Performed in sagittal plane with real-time assessment and cine clip recording
• The posterior compartment sliding sign is used to evaluate the POD and has two
components:
• Gentle pushing pressure is applied on the cervix with the probe
The anterior rectum should slide relative to the cervix and vagina
• The hand is used to apply gentle pushing pressure on the fundus of the uterus
while imaging in the sagittal plane
The anterior bowel should slide relative to the uterus
• The anterior compartment sliding sign is used to evaluate for uterovesical
obliteration:
• Uterovesical obliteration is nonspecific; it is being seen increasingly with
increasing cesarean section prevalence

35. Positive Sliding Sign
Posterior cervix slides relative to anterior rectum Fundal uterus slides relative to bowel
(incidental intrauterine device)
Sliding of the structures is considered a POSITIVE sliding sign
Positive is normal

36. Negative Sliding Sign
Posterior cervix and rectum move together and
do not slide separately
Lack of sliding is considered a NEGATIVE sliding sign
Negative is abnormal
A negative sliding sign predicts POD obliteration
-If one or both of the two components are negative, the POD
is obliterated (with a reported accuracy of 93%-97%)
Endovaginal US enables dynamic real-time assessment of
the sliding sign
 POD obliteration is associated with a three-times
increased risk of bowel involvement
 Critical to surgical planning
 Reflects the presence of nonspecific pelvic
adhesions
Can be better appreciated during recoiling, as the
transducer is slowly withdrawn
(Endometrioma in cul-de-sac)

37. Step 4: Detection of US Soft Markers (4,6)
• Increases diagnostic value of TVS
• Subjective findings that are indicative of pelvic disease
• Superficial endometriosis and adhesions are more likely to be present when soft markers are detected
• SST assessment
• During TVS, patient is asked to indicate sites of pain when gentle pressure is applied with the probe
• The identification of focal areas of pain is associated with the presence of endometriosis
• Tenderness-guided US
• Dedicated attention to sites of pain
• Increases sensitivity and specificity for detection of endometriosis findings
• Ovary mobility assessment to determine whether ovary is freely mobile or fixed
• Apply pressure between uterus and ovary to assess if they separate from each other
• Apply pressure to ovary to see whether it moves relative to other structures
• Loculated fluid
• Adhesions may be seen as thin strands within pelvic fluid

38. Detection of sonographic soft markers in a 38-year-old woman with
right lower quadrant pain and a history of severe endometriosis
Hypoechoic focal bowel DIE nodule
with tiny hyperechoic foci adjacent to
the right ovary (RO), with extension
along and thickening of the USL. Patient had focal tenderness
Thin strands in fluid are adhesions forming a peritoneal inclusion cyst around the right ovary
Owing to adhesions, the
DIE nodule and ovary are
not separable with
compression
RO

39. Detection of soft markers in a 25-year-old woman with chronic
pelvic pain
Kissing ovaries: Ovaries that
are located within the pelvic cul-
de-sac, are adherent owing to
pelvic adhesive disease, and
cannot be separated with gentle
pressure applied with the US
probe
*
*
Bilateral Endometrioma (*)

40. Search Summary
ONE: Uterus and Adnexa
-Are there findings of adenomyosis?
-Is there an endometrioma (or
endometriomas)?
-Is there a hydro- or hematosalpinx?
TWO: DIE
- Are there hypoechoic nodules in:
-anterior compartment (bladder)?
-posterior compartment (bowel, RVS, vaginal fornix, USL)?
Three: Sliding Sign
-Does cervix move relative to rectum?
-Does uterus move relative to bowel?
Four: Soft Markers
- Is there SST?
- Are organs mobile?

41. Sonographer Preliminary Findings Worksheet
ENDOMETRIOSIS
Patient: ___________________________________________ MRN: _____________________________
Additional history: _____________________________________________________________________
UTERUS:
Adenomyosis Y N
Other: _______________________________________________________________________________
_____________________________________________________________________________________
OVARIES:
Endometrioma Y N
# _________
Size _______
R B L
Mobile R Y L N
Tender R Y L N
Other: _______________________________________________________________________________
_____________________________________________________________________________________
ADNEXA/CULDE SAC:
Hydrosalpinx R Y L N
Peritoneal Inclusion Cyst R Y L N
Free Fluid Y N
Adhesions Y N
Other: _______________________________________________________________________________
_____________________________________________________________________________________
Sonographer: _______
Date: ______________
DEPOSITS: Tender Mobile
Bladder/Ureter Y N + − + −
Bowel Y N + − + −
USL Y N + − + −
RV Y N + − + −
Describe: _____________________________________________________________________________
_____________________________________________________________________________________
SLIDING SIGN*:
Cervix + −
Fundus + −
Bladder + −
Describe: _____________________________________________________________________________
_____________________________________________________________________________________
*Note: a + sign is normal sliding
TENDER:
Describe: _____________________________________________________________________________
_____________________________________________________________________________________
KIDNEYS:
Hydronephrosis R Y L N
Other: _______________________________________________________________________________
_____________________________________________________________________________________
_____________________________________________________________________________________
_____________________________________________________________________________________
_____________________________________________________________________________________
_____________________________________________________________________________________
Example worksheet outlining the components and possible findings can be a helpful guide
during examination and documentation
NOTE: Plus and minus signs indicate that the given deposit is (+) or is not (−) tender or mobile, or that the sliding sign is present (+) or absent (−). B = bilateral, L = left, MRN = medical record
number, N = no, R = right, RV = rectovaginal area, USL = uterosacral ligaments, Y = yes.

42. Limitations of TVS (4,5,8,27,28)
• Requires knowledgeable and experienced operators
• Requires training, education, and time
• In a cohort of experienced sonographers, a minimum of 40 examinations need to be
performed to become proficient in performing sliding sign assessment
• Assessment of fundus is best performed with two operators
• Time-consuming: Examination time is 45 minutes
• Technical limitations
• Patient factors: prior surgery, body habitus, distorted anatomy (eg, leiomyoma),
intolerance of probe motion due to pain
• Limited field of view
• Accuracy of disease detection is location dependent
• Accuracy in DIE detection is greatest in the bowel

43. To review, name 3 diagnostic advantages of TVS in the
evaluation of endometriosis:
The imager can evaluate localized tenderness with the endovaginal
probe in real time.
Compression maneuvers such as the sliding sign maneuver can be
performed to evaluate for pelvic adhesions and predict POD
obliteration.
Real-time optimization of parameters to dedicatedly examine the
individual pelvic compartments.

44. Summary
• Accurate assessment of disease location and extent is necessary to guide both medical
and surgical management, especially for pre-operative planning
• Use a dedicated ultrasound protocol to evaluate the varied manifestations
 Evaluate the Uterus + Adnexa
 Search Anterior / Posterior compartment for DIE
 POD obliteration assessment with sliding sign
 TVS soft markers
• There is a learning curve with more experienced sonographers and imagers performing
better
 Dedicated protocol training and experience are necessary
 Accuracy is higher with more experienced operators
Closing Thoughts
• This activity has demonstrated the unique dynamic features of US that yield
key information regarding patients with endometriosis.
• TVS is an excellent tool for the evaluation of endometriosis provided the
imager is well versed in how to look, where to look, and what to look for.
• Our practice experience supports the theory that once you start to
dedicatedly and systematically look, you will find the various manifestations
of endometriosis, including DIE deposits, in patients who have this disease.

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