Transcript 6 - gu365 cases 2009..

GUT CASE
INVESTIGATION
LECTURE 1
Nephrolithiasis(renal stones)
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Epidemiology
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Risk Factors
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Up to 10% by age 70, usu in 3rd to 4th decade
4:1 M to F ratio
More prevalent in the South
Hypercalcemic states, Crohn’s, stents, RTA, infection,
gout, hypercalciuria, hyperuricosuria, cystinuria
Symptoms
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Asymptomatic, flank pain, hematuria
Composition
OPAQUE contains calcium +/ phosphate
 Calcium calculi
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Ca oxalate, Ca phosphate
Struvite calculi
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Magnesium ammonium phosphate= triple phosphate
SEMI OPAQUE contains sulphur
 Cystine calculi
LUCENT
 Uric acid stones;Xanthine
 Matrix (coagulated mucoid material)
CT Imaging of Stones
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Essentially all renal and ureteral calculi have high
attenuation on non-contrast CT (all but matrix stones
have atten of > 100HU)
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CT has sensitivity of 97% and specificity of 96%
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Can also see hydronephrosis, hydroureter, renal
enlargement, or perirenal stranding
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Must differentiate from phlebolith which is a
calcified blood clot in a pelvic vein.(appearance:
round/ovoid, smooth, central lucency, in true pelvis)
Nephrolithiasis
Radio
opaque stone
in calyx
Images: BIDMC, Dept of Radiology, 2001.
Hydronephrosis
Dilated urine filled
pelvis
Stent
Hydroureter
Stent
Images: BIDMC, Dept of Radiology, 2001.
Obstructive Uropathy
Radiologic Assessment
Anatomy: Urinary Tract
Renal Capsule
Calyx
Superior
Operculum
Cortex
Medulla
Papilla
Pelvis
Fornix
Inferior
Operculum
http://www.urostonecenter.com/images/p1.gif
Unequivocal Obstructive
Uropathy
= Urinary tract obstruction
Unequivocal: clear etiology
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Obstruction may be at any
site within GU tract
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Evidence of post-renal
failure
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Variable presentation
based on etiology
Sign: Hydronephrosis = dilatation of renal pelvis and ureters
Pathophysiology of Obstructive
Uropathy
Hydronephrosis
Mechanical or functional obstruction
Back up of urine flow = increased renal pressure
Tubular dilatation
Initial increase in renal blood flow
Decrease in renal blood flow
Increase in renal lymphatic flow
Initial increase in ureteral peristalsis & pelvic
muscle hypertrophy
Muscle stretched & atonic  Aperistalsis
Dilatation of ureters and renal collecting duct system
Parenchymal Atrophy
Renal failure
Pathogenesis of unilateral hydronephrosis. Smith’s Urology p.181
How Acute Obstruction leads to
Dilatation and Decreased Tubular
Function
Pathology
Dilated renal pelvis (arrow), external view
http://www.smbs.buffalo.edu/pth600/IMCPath/y1case/y1ans21.htm#Obstructivelesionsintheurin
arytract
Dilated pelvis & calyces, renal atrophy, cut surface
http://www.smbs.buffalo.edu/pth600/IMCPath/images/Year1/Hydronephrosis_Gross-_Robbins.jpg
Clinical Presentation: Obstructive
Uropathy
Lower and Mid Tract
(Urethra and Bladder)
Hesitancy in starting urination
Lessened force
Weak stream
Terminal dribbling
Hematuria
Burning on urination
Cloudy urine (infection)
Acute urinary retention
Upper Tract
(Ureter and Kidney)
Flank pain radiating along ureter
course (distension)
Gross hematuria
Nausea/Vomiting
Fever/Chills
Burning on urination
Cloudy urine with infection
Bilateral uremia
N/V/weight loss
Renal insufficiency  Consider UTO in all patients with unexplained renal insufficiency
Urine Output Changes
Anuria = complete bilateral UTO
Partial obstruction  normal to elevated UO
Hyperkalemic renal tubular acidosis
Hypertension
Lab Abnormalities: normal, microscopic/gross hematuria, pyuria, azotemia, uremia, anemia
(2/2 chronic infection, ACD), leukocytosis
Think Anatomically:
Where is obstruction?
Proximal
etiology
Series: 53 of 380 patients
52/53 in lower 1/3 of the ureter.
Unilateral
hydronephrosis
Causes:
Ureteral stones 64%
Most Common in Distal Ureter
Ureteral edema or lucent
stones 30%
Systemic or
Neoplasms 4%
Distal etiology
Inflammatory disease 2%
Chen et al., J Emerg Med, 1997: 15; 3. 339 – 343.
Bilateral
hydronephrosis
Acute Obstruction and Anuria
Acute complete, bilateral obstruction
= Medical Emergency
Patients may die from acute
renal failure with
oliguria/anuria
Requires prompt
recognition and possible
surgical intervention
CT examination: Postcontrast axial scan: The retroperitoneal giant tumor mass compresses the
right ureter and causes hydronephrosis (arrows).
http://www.szote.u-szeged.hu/radio/panc/alep8c.htm
Diagnosis
Early diagnosis and decompression is critical to
prevent renal failure
Continue to Radiologic work-up
Ultrasonography
Test of Choice for Suspected Urinary Tract Obstruction
Screening test
Indications: Renal failure of unknown origin/Hematuria/Signs of UTO/Urolithiasis
Sensitivity for detection of chronic obstruction: 90%
Sensitivity for detection of acute obstruction: 60%
Advantages:
No allergic/toxic complications of radiocontrast media
Fast, inexpensive
Diagnose other causes of renal disease in patient with renal insufficiency of unknown origin
Polycystic Kidney Disease
Disadvantages
Nonspecific
Rarely identifies cause
False positive rate: < 25% with minimal criteria (operator dependent)
Any visualization of collecting systems
False negative with acute obstruction, dehydration, sepsis
Bowel Gas decreases sensitivity
Ultrasound – Normal Kidney
Normal renal
parenchyma,
hypoechoic,
normal function
Normal renal fat,
no dilatation of
collecting
system,
hyperechoic
Ultrasound – Obstructive
Uropathy
Renal
parenchyma,
hypoechoic
Dilated collecting
duct, hypoechoic
(fluid)
Compressed
renal fat,
hyperechoic
CT: normal renal parenchyma with
proximal stone, no obstructive
uropathy
Noncontrast
CT
Enhancing
calculus in
interpolar
portion of R
Kidney
Kawashima et al., RadioGraphics 2004;24:S35-S54
CT: Hydronephrosis due to
retroperitoneal fibrosis (soft tissue)
CT (postcontrast):
Giant retroperitoneal
tumor mass
compressing the right
ureter, causing
hydronephrosis with
compression of renal
parenchyma (arrows).
http://www.szote.u-szeged.hu/radio/panc/alep8c.htm
CT: Obstructive Uropathy
Dilated Renal
Pelvis
Proximal
Stone
CT (postcontrast):
Obstructive left-sided
uropathy with
proximal ureteric
stone
PACS, Courtesy of Dr. D. Brennan
IVU: Intravenous Urogram
Intravenous Pyelogram = Excretory Urogram
1.
Scout film  calculi?
2.
IV bolus of radiocontrast dye (ionic contrast)
3.
Series of plain films demonstrate kidneys, ureters,
urinary bladder
4. Upright film post-void to evaluate for obstruction
Advantages
Anatomy
Pathology Location
Rough indicator of function bilaterally
Low false positive rate
Detects associated conditions
Papillary necrosis  intralumenal filling defect
Caliceal blunting from previous infection
Disadvantages
Cumbersome
Requires radiocontrast
Need bowel prep with conventional IVU
Radiation dose
Need cross-sectional imaging follow up
CT Urography
Evaluate urinary tract for flow defects
Noncontrast Scout first: Urolithiasis
Coronal reconstructions: visualize entire urinary tract
Advantages over Conventional IVU
Speed
Sensitive to renal parenchyma abnormalities
Simultaneous evaluation of both renal parenchyma and
urinary tract
Cross-sectional imaging
Disadvantages
Radiation dose
Ionic Contrast reactions/cannot be used in patients in
renal failure
Kawashima et al., RadioGraphics 2004;24:S35-S54
Normal CT Urogram
CT Urography
Total Body
Opacificantion
Nephrogram
Pyelogram
Normal CT Urogram
CT Urography
Total Body
Opacificantion
Nephrogram
Pyelogram
Normal CT Urogram
CT Urography
Total Body
Opacificantion
Nephrogram
Pyelogram
Normal CT Urogram
CT Urography
Total Body
Opacificantion
Nephrogram
Pyelogram
Normal CT Urogram
CT Urography
Total Body
Opacificantion
Nephrogram
Pyelogram
Pt. JL, PACS, Courtesy of Dr. AC Kim
Normal CT Urogram
CT Urography
Total Body
Opacificantion
Nephrogram
Pyelogram
Normal CT Urogram
CT Urography
Total Body
Opacificantion
Nephrogram
Pyelogram
Contraindications for IVU/CTU
History of allergy to IV contrast
Bronchospasm, laryngeal edema, anaphylactic shock
May use with history of minor allergic reactions with preprocedural steroids, antihistamines
(diphenhydramine) 12 hours prior to study
Renal insufficiency
Pregnancy = relative contraindication (radiation exposure)
MR Urogram can be used
Likewise: children  minimize radiation doses
Pts taking oral hypoglycemics (metformin) should stop taking meds prior to study
May resume after renal function is confirmed normal
Risk of lactic acidosis
Must be Physician-Supervised
- Contrast reactions
- Minimize no. of images
- Minimize radiation
- May use Fluoroscopy
MR Urography
Sagittal contrast-enhanced excretory
MR urography obstructing right
sided papillary TCC
A. Unenhanced MR urography
Heavily T2 weighted
B. Gadolinium-enhanced excretory MR urography
C. Excretory MR urography + diuretic
10 mg furosemide IV
Gadopentetate dimeglumine
Advantages:
Distinguishes adjacent soft tissue abnormalities
With Gadolinium: functional information
No ionic contrast  OK in renal failure
No radiation  children, pregnancy women
Drawbacks
High cost
Low sensitivity in detecting calcifications
Time intensive
Metallic implants/Foreign Body = Contraindications
Blandino et al., AJR 2002; 179: 1307 -1314
Excretory Urogram/CTU/MRU
Acute Obstruction
Mild  Moderate  Marked
Kidney minimally enlarged
Dense Nephrogram
• Preferential absorption of Na and
water from diseased tubules =
concentration of contrast
Delayed appearance of contrast in
collecting system
= delayed function
Poor concentration of contrast in the
collecting tubules
No ureteral dilatation acutely
Ureters not tortuous
http://asia.elsevierhealth.com/home/sample/pdf/314.pdf
Excretory Urogram/CTU/MRU
Chronic Obstruction
Partial  Complete
Progressive dilation of collecting system
and ureters/tortuous
Urectasis = dilated ureter
Decrease number of nephrons
6-12 weeks: irreversible loss of renal
function
“Shell nephrogram” parenchymal
atrophy
Collecting system: blunt calyces/forniceal
angles
Calyceal Clubbing
Blandino et al., AJR 2002; 179: 1307 -1314
Patient JL – Bladder Mass
Left Bladder mass
surrounding UO
Diagnosis:
57 yo M with known Bladder
CA with left hydronephrosis
secondary to left bladder
cancer.
Management
Foley placement for
immediate decompression.
Pt urinated following
catheter removal and was
cleared for d/c
Urology consult for possible
stent placement
Renal Cystic Disease
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Very common 50% of pts over age of
50
Assoc w/ many syndromes, etiology
unknown, probably arise from obstructed
tubules or ducts
Most commonly asymptomatic
Rarely, may have hematuria, HTN, cyst
infection, or mass effect
CT Characteristics of
Simple Cysts
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Smooth, imperceptible cyst wall
Sharp demarcation from surrounding renal
parenchyma
Water attenuation (<15 HU), homogenous
throughout lesion
Non-enhancing
Simple cysts are w/o septations or calcification
May have slight elevation of adjacent renal
parenchyma  Beak sign
Type I Simple Cyst
Bird Beak
Sign
Aortic
aneurysm
Simple
Cyst
Images: BIDMC, Dept of Radiology, 2001.
Inferior vena
cava with
filters
Type IV Cystic Neoplasm
Complex
renal mass
infiltrating
lvc
Images: BIDMC, Dept of Radiology, 2001.
Conditions Associated with
Multiple Cysts
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Autosomal Dominant PCKD
Autosomal Recessive PCKD
Acquired Cystic Disease (hemodialysis
pts)
Von-Hippel-Lindau disease
Tuberous Sclerosis
Medullary Sponge Kidney
Benign Masses
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Cysts
Angiomyolipoma
Oncocytoma (via epithelial cells of prox tubule)
Renal Adenoma
Mesoblastic Nephroma (hamartomatous tumor, usu
present at birth)
Hemangioma
Various Renal Pelvic Tumors(papilloma, angioma,
fibroma)
Hematoma
Angiomyolipoma
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Hamartomas containing fat, smooth muscle, and
blood vessels
Usually asymptomatic, but may spontaneously
bleed
Large AMLs resected or embolized
Multiple AMLS usually Associated w/ tuberous
sclerosis
On CT *fat attenuation in mass*, strong
contrast enhancement (RCCs rarely contain fat),
no Ca2+
Angiomyolipoma
Note fat
content
Images: BIDMC, Dept of Radiology, 2001.
Malignant Masses
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Renal Cell Cancer
Transitional Cell Cancer
Wilm’s Tumor
Nephroblastomatosis (multiple rests of
embryologic metanephric blastoma)
Lymphoma
Metastases (lung, breast, colon, melanoma)
Renal Cell Ca
Most common primary renal malignancy (85% of
primary renal tumors)
Assoc w/ smoking, family hx, age, Von HippelLindau, Acquired Cystic Disease/chronic dialysis,
phenacetin abuse
Presentation: Hematuria, flank pain, wt loss, palp
mass, fever, anemia, paraneoplastic syndromes
liver enzymes w/o mets Stauffer syndrome
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CT characteristics
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Variablefrom complex cyst to large,
heterogeneous renal mass
Generally enhancing
May have calcifications
May have hemorrhage and central necrosis
Usually no fat
Renal Cell Ca
Images: BIDMC, Dept of Radiology, 2001.
RCC
Images: BIDMC, Dept of Radiology, 2001.
Renal Trauma
Anatomy of the Kidney
Renal blood supply
IVC
Ureter
Renal arteries
Renal veins
Be suspicious of renal
injury with broken ribs
2
Anatomy of the Kidney
3
Prevalence of Renal Trauma
• 10-20% of trauma pts. have GU involvement
• 45% of GU trauma is renal
• 20-30% of renal trauma pts. have associated
abdominal injury
4
Mechanisms of Renal Trauma
• Blunt trauma (80%): MVA, falls, assaults
• Penetrating trauma (20%): gunshot, stabbing,
impalement
• Predisposing factors: preexisting renal conditions
(tumors, hydronephrosis), children, associated
abdominal injuries
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Clinical Presentation of Renal Trauma
• Gross or microscopic hematuria (absent in 5%)
• Flank pain/ecchymosis
• Hemodynamic instability
• Presence of other abdominal injuries
6
Patient 1: An illustration of imaging modalities
• 18 yo male sustained stab
wound to R flank
• P=180, BP 130/80, Hct 36
• CXR nl.
• Why image and with which
modality?
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Indications for Imaging
• Gross hematuria
• Microscopic hematuria with
hemodynamic instability
• Persistent microscopic hematuria
• Significant MOI
8
Radiologic Imaging of Renal Trauma
CT with IV contrast
• Gold standard, high sensitivity
• Immediate and delayed post-contrast
images to view collecting system
• Allows diagnosis and staging
• Images abdomen and retroperitoneum
• Not for hemodynamically unstable pts.
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Patient 1: CT with IV
contrast
Normal attenuating
kidney
Peri-renal
hemorrhage
10
Patient 1: CT with IV contrast
Contrast
extravasation
11
Patient 1: CT with IV contrast
Renal laceration
with extravasation
of contrast
Retroperitoneal
hematoma
12
Radiologic Imaging of Renal Trauma Cont.
Intravenous pyelography
• Unable to evaluate abdomen
and retroperitoneum
• Inadequate for
grading renal injury
Image from Trauma.org
• Used in unstable pts prior to
surgery to identify functioning
contralateral kidney
Extravasation of contrast from R kidney
13
Radiologic Imaging of Renal Trauma Cont.
Renal Angiography
• Delineates vascular injury
(intimal tears, pseudoaneurysm,
AV fistula)
• Use when CT equivocal
and continued hemorrhage
• Use for endovascular repair
(embolization, stenting)
Image fromTrauma.org
Devascularization of L kidney
14
Radiologic Imaging of Renal Trauma Cont.
Renal ultrasound
• Bedside US in ED allows
evaluation of abd/pelvic
injury/fluid accumulation
Subcapsular hematoma
• High false neg. rate
for renal injury
• Used in areas without
CT, or for follow up
kidney
15
Patient 2: An Illustration of Injury Staging
• 17 yo unrestrained driver
MVA c/o RLQ pain
• VSS
• Hct 45.7, BUN 15, Cr 1.2
• CXR, cervical, lumbar, pelvic
plain films nl.
• CT demonstrates renal
laceration
• How severe? How manage?
16
AAST Organ Injury Scale - Renal Injury
Grade I Contusion:
Microscopic or gross hematuria, urological studies normal
Hematoma: Subcapsular, nonexpanding without parenchymal laceration
Grade II Hematoma: Nonexpanding perirenal hematoma confined to renal retroperitoneum
Laceration: <1cm parenchymal depth of renal cortex without urinary extravasation
Grade I and II injuries managed conservatively (observation, serial Hct)
17
AAST Renal Injury Scale Cont.
Grade III Laceration: >1cm depth of renal cortex, without collecting system rupture
or urinary extravasation
Grade IV Laceration: Parenchymal laceration extending through the renal cortex,
medulla and collecting system
Vascular:
Main renal artery or vein injury with contained hemorrhage
Grade III and IV injuries are now managed conservatively
18
AAST Renal Injury Scale Cont.
Grade V Laceration: Completely shattered kidney
Vascular:
Avulsion of renal hilum which devascularizes kidney
Image from www.trauma.org
Surgery! Salvage vs. nephrectomy
19
Renal Trauma Conclusions
• Look for renal trauma in pts with
abdominal trauma and significant MOI
• CT with contrast
• Grade severity of injury
• Injuries requiring surgery: vascular injury,
shattered kidney, expanding hematoma
• 80-90% renal injuries treated conservatively
with
• remarkable resolution!
23
Imaging in the
Evaluation of Female
Infertility
Infertility
Inability to conceive after one year of intercourse
without contraception
Epidemiology
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Affects 1 in 7 American couples
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Rate has been stable over the past 50 years
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Advances in assisted reproductive technologies
(ART) has increased interest in infertility
treatment
Infertility - Causes
Male Factor – 40%
Azoospermia
Sperm defect or dysfunction
Chronic Illness
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Combined Factors – 10%
Female Factor – 40%
Advanced age
Anovulatory cycles
Congenital anomalies
Acquired structural defects
Endocrine abnormalities
Unexplained – 10%
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Infertility – Radiologic Evaluation
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Largely focuses on female factor infertility
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Several congenital and acquired conditions affect
female reproductive function
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Complete evaluation of the female reproductive tract
must include cervical, uterine, endometrial, tubal,
peritoneal, and ovarian factors
Menu of Tests
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Hysterosalpingogram (HSG)
Ultrasound (US)
Sonohysterogram (SHG)
Magnetic Resonance Imaging (MRI)
HSG
Hysterosalpingogram
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Historically the mainstay in infertility imaging
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Indications: evaluation of uterine cavity and
patency of tubes
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Limitations: does not aid in characterization of
uterine wall or ovarian pathology
Ultrasound
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Test of choice for imaging the female pelvis
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No radiation exposure
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Indications: evaluation of ovarian, uterine wall, and
adnexal pathology
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Limitations: additional imaging may be needed for
pre-surgical characterization and localization of
pathology
MRI
Excellent soft tissue characterization
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Indications: guides interventional radiology
and surgical management of infertility by
identifying size, number, and location of
pathology
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Female Reproductive Tract
www.ethal.org.my/.../ 181rmgUterus.html
Cervix
Cervical Stenosis
Fallopian Tube
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vary
Narrowing of the cervix due
to adhesions or scarring
Patients complain of painful
or absent periods
Complication of cone
biopsy
Blocks entry of sperm
Ovary
Uterus
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Adhesions
Cervix
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Vagina
www.drkline.com/ risks.html
Cervical Stenosis
HSG Findings:
•Internal os < 1mm
•Inability to advance
catheter
Normal HSG
•Non-opacified
uterine cavity
Vagina
Cervical Stenosis
BIDMC, PACS
Uterus
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Synechiae
Fibroids
Polyps
Congenital Anomalies
Synechiae
Asherman Syndrome
Intrauterine adhesions caused by trauma, infection, or
instrumentation
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Healing granulation tissue forms bridges across the
cavity
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Infertility may result from obliteration of the cavity or
obstruction to implantation
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Synechia
HSG findings:
Filling Defect
Linear
Irregular
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Synechia
BIDMC, PACS
Synechia
US Findings:
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Echoic
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Linear
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Extends from
one wall to
opposite wall
Synechia
Fibroids
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Benign, smooth muscle
tumors of the uterus
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Found in 20-30% of
reproductive aged women
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Affects fertility by
interfering with
implantation
Fibroids
HSG Findings
Scalloped endometrial lining
Fibroids
Ultrasound aids in characterization of fibroids.
US Findings:
Hypoechoic mass 
May be submucosal,
intramural, or subserosal
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Uterine enlargement or
distortion may be seen
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12
Fibroid
Fibroids
MRI aids in:
• characterization and
localization of uterine
wall pathology
•pre-surgical planning
Fibroids
BIDMC, PACS
Uterine Anomalies
A defect in the embryologic development of
the Mullerian system can cause congenital
uterine anomalies
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There are 7 classifications of anomalies
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All can be identified by imaging
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Uterine Anomalies
Class II - Unicornuate
Normal
Class III - Didelphys
Class V - Septate
Class IV - Bicornuate
Class VI - Arcuate
http://www.emedicine.com/radio/topic738.htm
Class VII - DES
Uterine Anomalies
Two classes must be differentiated in the infertility work-up:
Bicornuate:
Septate:
• Indented fundus but otherwise normal
uterine wall
• No affect on fertility
• No infertility treatment necessary
• Fibrous band projecting from fundus
into uterine cavity
• Interferes with implantation
• Surgical removal increases fertility
http://www.emedicine.com/radio/topic738.htm
Uterine Anomalies
Irregularly shaped uterine cavity on HSG  MRI
BIDMC, PACS
Uterine Anomalies
The irregularly shaped uterus seen on HSG and
MRI in the previous slides was determined to be
an arcuate (class VI) uterus. It is on the
spectrum
of bicornuate and is believed to be a normal
variant with no affects on fertility.
Fallopian Tubes
Obstruction
 Pelvic Inflammatory Disease
 Fibroids
 Endometriosis
 Adhesions
 Tubal spasm
Fallopian Tubes
Isthmus
Ampulla
Infundibula
Fimbria
Fallopian Tubes
Left Proximal Obstruction
Right Proximal Obstruction
Peritoneal Cavity
Adhesion
 Endometriosis
 Post surgical
 Post infection
Difficult to image directly but an irregular pattern
of dye overflow on HSG may raise suspicion.
Ovaries
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Endometriosis
Polycystic Ovary Syndrome (PCOS)
Endometriosis
C6
US Findings:
•Round
Bilateral
Endometriomas
•Symmetric
•Hypoechoic cysts
•Low-level echoes
Ovarian stroma
•Persistent
PCOS
US Findings of PCO:
Bilateral
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Round, echogenic ovaries
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10-12 small follicles
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PCOS is a clinical diagnosis.
US findings of polycystic
ovaries is neither necessary nor
sufficient, but in the
right clinical setting may be
indicative of the diagnosis.
EW is 9 weeks pregnant today.
Early OB Ultrasound at 7 weeks 4 days.