Ovarian Cysts - Common...
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Transcript of Ovarian Cysts - Common...
• Normal ovaries ▫ premenopausal ▫ Post-menopausal
• Functional cysts ▫ Follicular cyst ▫ Corpus luteum cyst ▫ Hemorrhagic ovarian cyst
• Other Benign cystic and Cyst-like lesions ▫ Endometrioma ▫ Polycystic ovary syndrome ▫ Ovarian hyperstimulation syndrome - Theca lutein cysts ▫ PID with tubo-ovarian abscess
• Benign Cystic Ovarian Neoplasms ▫ Mature Cystic Teratoma ▫ Cystadenoma and Cystadenofibroma
• Malignant Cystic Ovarian Neoplasms ▫ Serous Cystadeno-Carcinoma ▫ Mucinous Cystadeno-Carcinoma ▫ Endometrioid Ovarian Carcinoma ▫ Cystic Metastases to the Ovaries
Normal ovaries
• premenopausal • The normal ovary : • 2 Million primary Oocytes at birth, • 10 mature each menstrual cycle • 1 Dominant Follicle /size of 18-20 mm by mid-cycle, • The others become Atretic and Fibrous. • After Ovulation, it collapses, and the Granulosa Cells
proliferate and swell to form the Corpus Luteum . • Over the course of 14 days the Corpus Luteum degenerates, to
Corpus Albicans.
• Graafian follicles :
• Normal ovary in Pre-Menopausal women contains :
• Several Anechoic, Simple Cysts (Graafian Follicles )
• Post-menopausal • The Ovaries are Smaller • Gradually Stop forming Graafian follicles. • However, that Follicular Cysts may persist several years
after menopause.
Functional cysts
• The Most Common Cystic Ovarian Lesions • Functional cysts are : Graafian follicles or Corpora Lutea that Have Grown Too
Large or Have Bled, but are otherwise benign. • Pre-Monoposal , Common • Post-Menopause , may be seen. • Even in Late menopause, may be seen in up to 20% of women.
• Follicular cyst • ≥ 3 cm, (usually 3-8 cm) • On US: as a Simple Unilocular, Anechoic Cysts / Thin,
Smooth Wall • No Enhancing Nodules /or other Solid Components, • No Enhancing Septations, • No Ascites (more than physiologic ) • Resolve Spontaneously on follow-up.
• Corpus luteum cyst • Corpus Luteum may Seal and Fill with Fluid or Blood, forming a
Corpus Luteum Cyst • US :A Small Complex Cyst with Wall Vascularity on power Doppler • the ‘Ring of Fire‘: The Characteristic Circular Doppler appearance • Good Through-transmission /no Internal Vascularity, • NOTE : Birth Control Pills prevent ovulation / NO Corpus Luteum Fertility Drugs (Ovulation Induction) / Increase Chance of
Developing Corpus Luteum Cysts.
• Another case • Typical 'Ring of Fire' on US • Pathologic examination ; Collapsed Bloody Cyst • DDx : EP
• Clinically : the Classic Presentation : Acute Pelvic Pain sometimes an Incidental Finding/ in an
Asymptomatic Woman • Sonographic Appearances Depends on : the Stage and Duration of the Cyst Formation. It can take any of the following appearances
Hemorrhagic Ovarian Cysts : Bleeding in a Graafian Follicle / or Follicular Cyst ,
• 1) Fishnet Weave or Fine Reticular Pattern • is the Commonest Presentation of these Cysts • Multiple Fine Strands of Fibrin giving a Net-like
Appearance • The Septa are Thin and/ Typically Non Vascular
• 2) Retracting Clot appearance • Clot formation and Subsequent Retraction in a
Hemorrhagic Ovarian Cyst • a Triangular, inhomogenous Clot in a part of the cyst
with Serous Fluid occupying the remainder of the cyst.
• 4) Rupture of HOC • An Unusual Appearance may be caused by rupture of the HOC
resulting in blood within the pelvis • As Echogenic Fluid surrounding the cyst and uterus DDx : It can mimic an EP
• Hemorrhagic Ovarian Cyst
• US : a Unilocular /Thin-walled Cyst /with Fibrin-strands or/ Low-level Echoes and /Good Through Transmission
• Doppler : No Internal Vascularity
• Diagnosis ? • A 23 y-o woman : • Severe Acute Pelvic Pain/+ β-hCG • A, Rt Adnexal Mass with an irregular thick rind (arrows) • B, Echogenic Fluid (arrows) adjacent to the Lesion
• This was mistaken for a Ruptured EP
• but was a Ruptured HOC at laparoscopy
• The patient had a concurrent very early Intrauterine Pregnancy
• 5) HOC resembling a Solid Ovarian Neoplasm • Echogenic Material within the cyst, • usually happens at Sub-acute Period with Early Stage of Clot Formation • Follow-up US will show Dramatic Changes within the HOC usually in 4 to 6
weeks • Color Doppler will show Lack of Flow within the Hemorrhagic Cyst
• Diffferential Diagnosis of HOC : • Most of the Causes of Acute Pelvic Pain can mimic
the Symptoms and Signs of HOC Acute Appendicitis and EP PID , and Mesenteric Adenitis. • Of these, EP is the most important condition : • Serum beta HCG and • Careful examination of the adnexal structures : On probe pressure, the ovary moves away from the
adnexal/ tubal mass in EP ) • The “Ring of Fire” sign can be seen in EP and in HC
• Endometrioma or Cystic Endometriosis • In 75% of patients Ovaries are involved • US Appearance can be Variable • Classic appearance ( 95% ) : as a Homogeneous, Hypoechoic Cyst
with Diffuse Low Level Echoes • Rarely ; Anechoic, Mimicking a Functional Ovarian Cyst • can be Multilocular / have Thin or even Thick Septations
• Mural Echogenic Foci , (1/3 of patients ) Cholesterol Deposits or/ Small Blood Clots or Debris • DDx from True Wall Nodules (At Doppler no Vascularity ). • In the presence of these foci, the diagnosis is Very Likely.
• A Cystic Lesion with a Hyperechoic Structure. • a wide range of DDx including : Ovarian Cystic Neoplasm with Solid Component Mature Cystic Teratoma with Hyperechoic Rokitansky Nodule Hemorrhagic Cyst with Clot Endometrioma with clot or debris.
Continue with the CT and MR.
• The next case • Unilocular, mildly Hypoechoic Ovarian Lesion with Through Transmission. • No Internal or Wall Vascularity on Doppler • DDx : either a HC or an Endometrioma.
Continue with the MR images • Hypointensity due to the presence of Deoxyhaemoglobin and
Methaemoglobin (shading sign), • Which is Very Suggestive of Endometrioma
• 6 months later a follow-up MRI • Bright on T1 and T1 Fat-Sat (indicating of Blood ) • T2 Shading (Hemorrhagic lesion ) • T1+C No Enhancement • Fluid-fluid Level (Re-Bleening in a Cystic Lesion ) • Duration : 6 Month • Bilateral Endometrioma Much More Likely than HC
T1
T1 +C
T2
T1 Fatsat T1
T1 +C
• (a) fat-satT1 Hyperintense signal
• (b) fat-satT2 : Shading and a T2 Dark Spot in the left adnexal lesion
• a 33-y-o woman Bilateral Pathologically Proved Endometriomas
• Ovarian Hyperstimulation Syndrome - Theca lutein cysts • Is usually Bilateral • Causes : • Hormonal Overstimulation by HCG, Throphoblastic Pregnancy,
Hormone Therapy, Pregnancy (rarely) • Imaging : Bilateral Ovarian Enlargement with Multiloculated Cyst
• theca lutein cysts: a young pregnant woman • US : • Bilateral Multiple cysts • An Invasive Uterine Mass, • Consistent with Invasive Molar Pregnancy.
Mature Cystic Teratoma • Characteristic US findings are: Hypoechoic mass with Hyperechoic
Nodule (Rokitansky nodule or Dermoid Plug) Usually Unilocular (90%) Calcifications / Ossification (30-60%) May contain Hyperechoic lines caused by Floating
Hair May contain a Fat-Fluid Level (fat floating on
aqueous fluid ) The presence of Fat is Diagnostic
• Mature (Benign) Cystic Teratoma
• A Cystic Mass, with a Hyperechoic Solid Mural Nodule, (Rokitansky Nodule or Dermoid plug )
• another case : • the ‘Tip-of-the-Iceberg‘ Sign: Acoustic Shadow from
the Hyperechoic Part • This may be Misinterpreted as Bowel Gas
(overlooked )
• Cystadenoma and Cystadenofibroma • Are Common Benign Ovarian Tumors (Serous or
Mucinous ) • Serous Cystadenomas : • Mostly Unilocular / Anechoic, (like a simple cyst) • Mucinous cystadenomas : • Mostly Multilocular with Thin Septa • The locules may contain Complex Fluid, due to
Proteinaceous Debris or Hemorrhage, or Both The Finding of Papillary Projections should raise the
Suspicion of Malignancy
Serous Cystadenomas • Left Ovarian Cyst /Anechoic , No Septations , No Ascites • However, a Nodule on the posterior wall /No Flow on Doppler DDx : Follicular Cyst with some debris /a Cystic Neoplasm
Can not be Excluded Work-up with MRI is recommended
• The next case • A Multiloculated Cystic Mass. • looks like a Cystic Ovarian Neoplasm , • but No Ovary could be identified. • Continue with the CT ›››.
• CT of the same patient • Multi-loculated Cystic Mass , Connected to the left ovarian
vein (arrow) • Thick Septations and Irregular Wall Thickening • DDx : a Benign or Malignant Ovarian Lesion • Pathology : Cystadenofibroma.
Malignant Cystic Ovarian Neoplasms
Remember : • The Role of Imaging is not : To Determine the Histological Nature of a Lesion, • but to : Possibly Distinguish Benign from Malignant Lesions
and , Guide Decisions on further Management • The Examples given Serve as a : Demonstration of Suspicious Imaging Features,
• Findings Indicating Possible Neoplasm:
• Large size While Benign lesions can be very large, the Likelihood of Malignancy Increases with Size.
• Thickened Vascularized Septations
• Thick Septa Indicates a Possible Neoplasm.
• Thickness > 3mm and Well-vascularized - while Non-Specific – Both Increase the Likelihood of Malignancy.
• Vascularized solid components Vascularized Nodularities, Papillary Projections, or Frank Solid Masses all Increase the Likelihood of a Neoplastic Nature.
• Vascularized thick, irregular wall
• Lesions with Thin Walls are More Often Benign
• Lesions with Thick, Irregular Walls are More Often Malignant
• However, there is some Overlap, making wall thickness a less useful criterion.
For example a Corpus Luteum cyst may also have a Thickened, Vascularized wall.
• Secondary findings associated with malignant lesions: Ascites ( Large quantities ), Lymphadenopathy and Peritoneal Deposits are Strongly Increase Likelihood of Malignancy.
• Serous Cystadenocarcinoma • US : • Left Ovary , a Complex Solid-Cystic mass • Right Adnex , a Very Large Complex Solid-Cystic Mass CT ›››
L,Ov R,Ov
• A Complex Solid-Cystic Mass with Thick, Enhancing Septations in the Rt Ov.
• These findings are Very Suspicious for a Malignant Cystic Neoplams.
• also Bilateral Lymphadenopathy (arrows). • Pathology : Serous Cystadenocarcinoma. • The Most Common type of Ovarian Cancer.
• Mucinous Cystadenocarcinoma • US : a Very Large Multi-loculated Cystic Lesion • Both Anechoic and Uniform Low-level Echoes (Proteineous / Hemorrhage /
Mucin ) • Thin and Avascular Septations • No Solid Components/No Ascites / No vascularity; in favor of Benign lesion However , the Zize / the Multi-loculated Aspect, are Suspicious for a Cystic
Neoplasm and Warant further evaluation • CT+C : Similar Findings • Pathology : Mucinous Cystadenocarcinoma of Low Malignant Potential.
Endometrioid Ovarian Carcinoma • US : Bilateral Enlarged Ovaries with Solid and Cystic Components The Complex Solid-Cystic Lesions + being Bilateral, are Suspicious
for a Cystic Neoplasm and Warrant Further Evaluation • CT : the Same Findings • The purpose of the CT = Staging (Left image; Peritoneal Implant )
• Pathology : Endometrioid Ovarian Carcinoma.
CT (or of MRI) is not to determine the Histologic Type For Epithelial tumors Staging is More Important
• Ovarian Metastase from Colon and Gastric ca
Cystic Metastases to the Ovaries Metastases to the ovary are Mostly Solid - but Cystic Metastases do occur.
• Cystic Metastases to the Ovaries • CT : Complex Cystic Masses in both ovaries • Colorectal Cancer (blue arrow) • Cystic Implants on the Peritoneal Reflection (red
arrow)