Chapter 17 Flashcards
Porstate anteriot relationship
Symphysis pubis
Pubic arch
Superior to prostate is
Seminal vesicles and bladder
Path of how semen is transported to outside
Epididymis Vas deferens Join seminal vesicles Ejaculatory ducts Urethra
Seminal vesicles
2 hollow, sacculated structures
Base bladder
Superior to prostate gland
Inferior to vas deferens and ureters
Prostate size and shape
Chestnut shape and size
Base of prostate is
Most superior part
Apex is
Most inferior part `
Ejaculatory ducts join urehtrea approx
Mid way through the prostate
Prostatic urethral divided into
Proximal and distal
Ducts
Transport seminal fluid
Seminal vesicles adds
Secretions to seminal fluid
Prostate adds
Secretions to seminal fluid
Urethra
Conduit for semen and urine
Prostaticovesical arteries come from
Internal illiac artery —> prostatic and inferior vesical artery
Inferior vesical artery supplies
The base of the bladder, seminal vesicles and ureter
Prostatic artery branches to
Capsular and urethral arteries
Supply prostate
Venous supply of prostate form
A network around the sides and base of prostate- deep dorsal penile vein draining into the internal iliac veins
2 regions of prostate gland
Fibromuscular region/stroma
Glandular regio
Fibromuscular region/stoma
Smaller sction
Anterior to the prostatic urethra
Less clinical significance
Glandular region
Posterior portion
Glandular region consists of what 4 zones
Peripheral
Central
Transition zone
Periurethral glandular tissue/zone
These zones have differing embryologic origins and susceptibilities to disease
Peripheral zone
Largest ~ 70% of glandular tissue
70% of cancers found here
posterior, lateral and apical regions of the prostate
Resembles “eggcup” holding the egg of the central gland
Central zone
25% of prostatic glandular tissue
5% of cancer located in Central Zone
Vas deferens and seminal vesicles
-enter at Central zone
Transitional zone
lateral aspects of the proximal prostatic urethra
~ 5% of glandular tissue
20 % of cancers
Second most common spot for cancers
Periurethral glandular zone
Tissue that lines the proximal prostatic urethra
Verumontanum
Divides the prostatic urethra
An area close to the centre of the prostate
separates proximal and distal prostatic urethra
Where ejaculatory ducts meet the urethra
Prostate problems suspected indicating problem
Size
Cancer
Feel lump on rectal exam
What lab value increases indicating prostate problem
PSA
Urinary problems indicating prostate problem
Nocturia
Frequency
Weakstream
Screening for prostate cancer
DRE and PSA blood test
PSA lab test
Glycoprotein produced exclusively by the prostate
Increase possible prostate cancer exists
Higher the elevation= more likely a cancer exists
IF PSA Is NOT IDEAL
Normal does not exclude cancer
Elevated doesnt mean cancer
Prostate zie increase causes PSA increase
20 to 40% of men have prostate cancer with normal PSA level
PSA ng% levels
<2.5 ng% = normal Rumack Curry text book <4 is normal
4-10 ng% = borderline
> 10 ng% = abnormal
Most men at any age have a PSA less than 1.5 ng/mL Normally*
PSA
provides a continuous index of risk CA Higher levels imply higher risk of cancer aggressive Serial PSA Tests Check if levels change over time
PSA density
PSA/volume = PSAd
biopsy can detect approx 80% cancer
patients avoid biopsies
marker for prostate cancer aggressiveness
course of action depending on aggressiveness
++ Doctor’s recommend biopsy PSA> 2.5 ng/mL
Suspicious nodule found DRE
Nodule on ultrasound with normal PSA
What anatomy is assessed for male pelvis ultrasound
Prostate
Seminal vesicles
Bladder
Transabdominal male pelvic ultrasound
Good for gross prostate and bladder evaluation
Limited to prostate size, shape and weight
Why?
Detail is inadequate
Almost all CA is posterior aspect of prostate not seen transabdominally
Need to evaluate Prostate Better
TRUS
Prostate gland procedure for US
Prostate gland can be imaged through the full bladder
Crude assessment of prostatic size
Patient drinks 20 to 32 oz water
Use a 3.5 to 5Mhz transducer
Scan with patient in supine position
2 planes
Protocol for prostate and seminal vessicle images
Transverse and Sagittal images prostate and seminal vesicles in both planes Prostate volume L x W x AP x O.523 Bladder prevoid and postvoid volumes Image RLQ and LLQ in sagittal
US of prostate limited to
Size shape and weight/volume of prostate
Evaluate bladder too
Normal prostate size
Weight = 20 grams
Approx. 4 cm (wide)x 3 cm (AP)x 3.8 cm (length)
Volume x 0.523= 23.8cc
Sonographic appearance of seminal vesicles
In the transverse plane Rt and Lt are seen
Should be symmetric
In sagittal plane they are ovoid structures
Prostate
Heterogenous
Should be symmetrical in shape and size
Major reasons to do TRUS
Prostate cancer evaluation
Biopsy
Guidance of therapeutic procedures
Less common reasons to do TRUS
Infertility
Prostatitis
Biopsy any accessible lesion in the pelvis for both men and women
Sonographers role for TRUS
Explain procedure to patient What will happen, list the steps Empty bladder Allow see prostate well Do you have any questions? Obtain Verbal consent If with biopsy will also need signed consent form and potential complications explained
Patient position for TRUS
Left lateral decubitus with legs together and bent up
Digital rectal exam before probe insertion if performed by Radiologist
Equipment for TRUS
Transrectal probe 7 to 11 MHz
Increased frequency= resolution
Biopsy gun
TRUS orientation of probe
Transverse or Axial
Anterior abdominal wall is top of screen with right side of patient on left side of image
Sagittal
Anterior abdominal wall top of screen, head of patient on the left of image – foot at right of image
TRUS scan planes
Transverse plane (axial)
Seminal vesicles at the base to urethra at the apex
Sagittal plane (90 degree turn)
From right to midline to left lobe
First in gray scale than using Doppler flow imaging in transverse plane for vascular symmetry
Prostate anatomy seen on TRUS
Better Resolution
Not able to distinguish the 4 zones
zones have similar echotexture
Divide Prostate anatomy into only 2
Inner gland = transitional+ anterior fibromuscular stroma glandular tissue+ internal urethra sphincter
Outer gland = (peripheral zone + central zone)
Prostate sonographic appearance
Outer Gland (sometimes referred to as peripheral)
uniform, homogenous texture
Slightly more echogenic than inner gland
Inner Gland (sometimes referred to as central)
More hypoechoic
heterogeneous
Prostate volume measurement
L x AP x W x 0.523
Surgical capsule seperates
Inner and outer gland
Not always seen in young males
Surgical capsule is not
A true capsule
Appearnce exterior of prostate gland
Outer Margin of the prostate “Prostate Capsule”
Not a True Membranous capsule
Clear interface between prostate and periprostatic fat
Exception posterolateral margin appears ragged
Prostate vascularity
Colour Doppler
Appears mildly to moderately vascular
symmetry
sonographic appeance of seminal vesical and vas deferens
Seminal vesicles
relatively hypoechoic, multiseptated structures
Vas deferens
Seen adjacent to Seminal vesicles
Normal vairants of prostate
Benign ductual ectasia
Prostatic calcifications and corpora amylacea
Corpora amylacea
Benign duuctal ectasia
Older men
Caused by atrophy and dilatation of prostatic ducts
Visible as single or grouped, 1 to 2mm diameter tubular structures in the peripheral zone
Prostatic calcifications and corpora amylacea
Normal findings
More common with advancing age
Bright echogenic foci or clumps in prostate
Corpora Amylacea
Proteinaceous debris
sound attenuation preventing TRUS examination
No clinical significance
usually not palpable
