Pelvis - Information

From iliac crests to pubic symphysis with anatomic structures extending inferiorly

What is the CT definition of the pelvis?

No

Does any tissue divide the abdomen viscera from the pelvis viscera?

Bony landmarks

What denotes the pelvis?

X-ray, contrast exams, ultrasound, CT, MRI, and nuclear medicine

What imaging modalities are used for the pelvis?

KUB; AP pelvis

X-rays of the pelvis are either part of a ____________ or an _____________

Hysterosalpingogram, barium enema, cystogram/voiding cystourethrogram (VCUG), and intravenous pyelogram (IVP)

What are some exams that use contrast that are conducted in the pelvis?

Female pelvis and prostate

What is ultrasound primarily used for in pelvis imaging?

Female pelvis and prostate

What is MRI primarily used for in pelvis imaging?

Bone scan, GI bleed scan, and nuclear cystogram

What are some different nuclear medicine tests that are conducted in the pelvis?

axially; bony algorithm; coronal; sagittal

A CT bony pelvis is obtained _________ in ________________ and reformatted in _____________ and _____________

Bony detail

What is a CT bony pelvis good for?

muscular; distensibility

The urinary bladder is a thin, strong ___________ wall characterized by its _________________

temporary reservoir for urine

The urinary bladder serves as a...

Perivesicular fat

What is the urinary bladder often surrounded by?

Pervesicular fat that surrounds it

What helps or allows for visualization of the urinary bladder?

Small bowel

What does the urinary bladder primarily cause a mass effect on?

Uterus and bowel

What organs cause a mass effect on the urinary bladder?

muscular

The ureter is a _______________ tube

Kidney collecting system with urinary bladder

What does the ureter connect?

Peristalsis

What occurs within the ureter?

Sigmoid colon

Tortuous structure that can extend well into abdomen, sometimes up to the transverse colon

Endoscopy (colonoscopy or sigmoidoscopy)

How is the sigmoid colon typically evaluated?

Barium enema and CT

What are imaging techniques used for the sigmoid colon?

air contrast

Barium enemas for the sigmoid colon can be used with or without...

diverticulitis; abscesses

CT of the sigmoid colon is used for _____________ and ____________

Mainly ileum

What part of the small bowel is visualized in pelvic images?

Cecum and appendix

First parts of large intestine that can extend well into the pelvis

common iliac arteries

The aorta divides into the...

internal and external iliac arteries

The common iliac arteries divide into the...

pelvic structures

The internal iliac artery goes to...

continues into the thigh

The external iliac artery...

Femoral artery

What does the external iliac artery become at the inguinal canal?

Superior rectal artery, middle rectal artery, and inferior rectal artery

What blood vessels supply the rectum?

Inferior mesenteric artery

Where does the superior rectal artery come from?

Anterior division of internal iliac artery

What does the middle rectal artery come from?

Middle and inferior rectum

What does the middle rectal artery supply?

Internal pudendal artery

Where does the inferior rectal artery come from?

Anorectal junction and anal canal

What does the inferior rectal artery supply?

portal

The superior rectal vein drains into the portal/systemic system

systemic

The middle and inferior rectal veins drain into the portal/systemic system with portocaval anastomoses present

Liver and mesenteric lymph nodes

Where do superior rectal cancers metastasize to?

Lungs (make way back to IVC to R atrium and eventually to lungs)

Where do middle and inferior rectal cancers metastasize to?

Vessels, lymphatics, muscles, and nerves

What does the pelvic side wall contain?

pararectal lymph nodes; inferior mesentery; sigmoid colon; inferior mesenteric; lumbar

Lymphatics from the upper half of the rectum ascend to _____________, then to lymph nodes in the __________________ of the ______________, and then to __________________ and _______________ lymph nodes

internal iliac lymph nodes

Lymphatics from the inferior half of the rectum drain into...

Prostate and seminal vesicles

What pelvic structures are unique to males?

urinary bladder

The prostate is located just inferior to the...

urethra

The prostate surrounds the...

accessory gland

The prostate is a(n) _______________ of the male reproductive tract

Ultrasound

What imaging technique is best for initially imaging the prostate?

MRI

What imaging technique is best for prostatic cancer?

CT

What imaging modality (other than US and MRI) is used to image the prostate?

Seminal vesicles

Paired elongated glands infero-posterior to the urinary bladder in males

Fructose and prostaglandins

What do the seminal vesicles contribute in an alkaline environment to the ejaculate?

CT and MRI

What imaging modalities are best for imaging the seminal vesicles?

Uterus, fallopian tubes, and ovaries

What pelvic structures are unique to females?

Uterus

Thick walled pear shaped hollow muscular structure of female pelvis

Endometrium, myometrium, and perimetrium

What are the layers of the uterus (deep to superficial)?

Endometrium

Inner mucosa of uterus

1-15 mm

Typical thickness of the endometrium in a pre-menopausal female

5 mm

Typical thickness of the endometrium in a post-menopausal female

Myometrium

Muscular wall of uterus

Perimetrium

Outer serous coat of uterus

Fundus, body, isthmus, and cervix

What are sections of the uterus?

Cornua (horns)

What are included in the fundus of the uterus?

Uterine/fallopian tubes

What extend laterally on each side of the uterus near the ovaries?

ultrasound

The uterus is most commonly imaged using...

Transabdominally or transvaginally

How are ultrasounds of the uterus typically done?

CT, hysterosalpingogram, MRI, and endoscopy

What are other types of imaging done for the uterus?

Ovaries

Gonadal tissue of females

Oocytes

What do the ovaries periodically discharge?

Into peritoneum

Where are the oocytes dispelled?

Follicular structure

How are oocytes dispelled?

Into uterine tubes

Once being dispelled into the peritoneum, where do oocytes go?

ultrasound

The ovaries are most commonly imaged using...

Transvaginally

How are the ovaries typically imaged with ultrasound?

CT and MRI

What other imaging modalities (other than ultrasound) are used for the ovaries?

Uterine part, isthmus, ampulla, and infundibulum

What are the four parts of the uterine tubes?

Uterine part

Short intramural part of uterine tubes passing through the wall of the uterus

Isthmus

Thick walled part of uterine tubes

Ampulla

Widest part of uterine tubes beginning at the medial end of the infundibulum

Ampulla of uterine tubes

Where does fertilization typically occur?

Infundibulum

Funnel shaped lateral part of uterine tubes that open into peritoneal cavity

Fimbriae

What extend off of the infundibulum and extend over the medial part of the ovary with one attaching superiorly?

Hysterosalpingogram

What is most commonly used to visualize the uterine tubes?

Ultrasound and CT

What imaging modalities can be used to visualize abnormal uterine tubes?

Intramural, prostatic, membranous (intermediate, posterior), and spongy (penile)

What are the four parts of the male urethra?

Intramural urethra

What part of the male urethra is found in the neck of the bladder?

4 cm

How long is the female urethra typically?

Ultrasound/Doppler

What are the testes typically imaged using?

Testicular masses, testicular torsion, testicular/epididymal infection, and scrotal fluid collections

What does ultrasound/Doppler of the testes help identify?