WEEK 1: Workshop: Imaging Urinary tract Flashcards
State the imaging exams for the urinary tract.
Imaging exams
– X-rays
* KUB (kidney-ureter-bladder)
* Intravenous urogram (IVU, IVP)
* Retrograde ureterogram and
urethrogram
* Voiding cysto-urethrogram
– Ultrasound
– CT
– MRI
State the functions of the kidney.
Function
– Regulation of vascular solutes and water
* Regulated blood pressure
– Filters the blood
State the 3 main parts of the kidney
Parts
– Cortex (glomerulus, proximal and distal convoluted tubule and some loop of Henle)
– Medulla (loop of Henle, collecting ducts)
– Collecting system
Describe how Contrast Imaging works.
- IV contrast
– Foreign substance
– Filtered and excreted by kidney - Intravascular (cortical phase)
- Excreted into collecting ducts (medullary phase)
- Excreted into the collecting system (excretory phase)
Describe how imaging with ultrasound works.
What produces echos?
State the following US characteristics.
– Time to echo return?
– Loudness of return?
Imaging with sound
* Emit sound wave
* Listen for echos
* Emit sound wave
* Listen for echos
* Etc.
– Difference in tissues (tissue planes)
* Different tissue – different acoustic
impedance
* Echo at interface
– Time to echo return
* Measure of depth
– Loudness of return
* Measure of difference in acoustic impedance
What are some causes of renal masses?
Focal Renal Lesions
- Neoplasm Focal Renal Lesions
– Malignant
* RCC
* TCC
* Lymphoma
* Mets
* Wilms tumor
– Benign
* Adenoma (oncocytoma)
* Angiomyolipoma (AML) (fat!)
* Multilocular cystic nephroma - Infection (abscess)
- Trauma
* Hematoma/Laceration/Fracture - Infarction
* Other
What is hydrouteronephrosis?
Hydroureteronephrosis is a medical condition characterized by the dilation of both the ureter and the renal pelvis (part of the kidney) due to an obstruction in the flow of urine. This obstruction can occur anywhere along the urinary tract, leading to a buildup of urine and subsequent swelling.
Hydroureteronephrosis
State the 5 causes.
- Obstruction
– Calculus
– Neoplasm - Primary
– TCC, Squamous cell - Pelvic malignancies
– cervix, uterus, ovary,
colon, prostate
– Strictures - Post op, XRT, TB
– Papillary necrosis
– Hematoma
– Pregnancy (minor, not significant) - Reflux
- Prior obstruction or reflux
Describe the Renal Vascular Supply
- Right and left renal arteries
– Arise from lateral aspect of aorta (occasionally multiple) - Right and left renal veins
– empty into the lateral aspects of the IVC
Renal arteries divide into
– Segmental arteries
* To each region
– Arcuate (interlobar) arteries
* Between medullary pyramids and between the cortex and medulla
– Intralobular arteries
* Enter nephrons
What is renal Arteriogram?
State its uses.
- Inject contrast into aorta or renal artery
Uses
1. Renal artery stenosis
– “Pre-renal” renal disfunction
– Renovascular HTN
* Unilateral stenosis
– Causes
* Atherosclerosis
* Vasculitis (PAN)
- Renal artery laceration
- Aneurysms and AVM’s
- Embolization neoplasms
What is Intravenous or CT Urogram?
Describe how it is done.
What are its uses?
- Imaging evaluation of the collecting system and ureters
- IVU
1. Inject water soluble contrast into a peripheral vein.
2. Kidney filters contrast
3. Excretes it into the collecting systems
4. Passes into the urinary bladder via the ureters - Uses
1. Hematuria
2. Strictures: a restriction
Describe the flow of urine to the bladder.
Urine excreted into
1. Calix
* Cup-shaped
* Surrounding medullary tip
2. Infundibulum
3. Renal pelvis
4. Ureter
* Peristalsing tube
5. Bladder
Ureter is a peristalsing tube. Peristalsing Tube
Cyclic, involuntary contractions propel fluid from proximal to distal.
State causes of its obstruction.
Obstruction
- Proximal dilatation
- Distal collapse
State causes of Ureteral Stricture.
- Prior surgery
- Urologic
* Other pelvic (GYN)
- Urologic malignancy
2. Transitional cell carcinoma (TCC) - Squamous ca.
- Extrinsic malignancy or inflammation
* Infections - TB
* shistosomiasis
* XRT
* Other - Polyureteritis cystica:
Description: Polyureteritis cystica is a rare condition characterized by the presence of small, cystic, fluid-filled lesions (cysts) in the ureter lining.
* Malicoplakia
Description: Malacoplakia is a rare inflammatory condition that can affect various organs, including the urinary tract. It is characterized by the formation of granulomatous lesions containing abnormal accumulations of certain cells.
Most common malignancy of the urothelium
– 95% in bladder
– 5% in upper tracts (kidney, collecting systems
and ureter)
* 10% of all upper tract neoplasms (most are RCC)
* Presentation
– Hematuria
* Imaging
– Filling defect (polypoid)
– Annular stricture with shelf-like margins
State the pathology.
Transitional Cell Carcinoma
Hematuria can be Microscopic vs. Gross.
State its causes.
- Etiology
1. Benign essential hemoglobinuria (micro)
2. UTI
3. Calculi
4. Urinary tract malignancies
(RCC/TCC/prostate ca)
5. BPH
6. Other - XRT: External beam radiation therapy is a medical treatment that uses high-energy X-rays to target and destroy or damage cancer cells.
- Endometriosis: Is is a medical condition that occurs when tissue similar to the lining of the uterus (endometrium) grows outside the uterus.
- Medical renal disease
- AVM: An arteriovenous malformation is an abnormal connection between arteries and veins, bypassing the capillary system.
- Trauma
Cyclic pelvic / groin / back pain
* Acute ureteral obstruction
* Cyclic due to peristalsis
* Cause: ureteral calculi
Namethe pathology.
Renal colic
Renal colic is a term used to describe the intense pain that occurs when a kidney stone moves from the kidney into the ureter—the tube that carries urine from the kidney to the bladder. Kidney stones are hard deposits that form in the kidneys from minerals and salts in the urine.
Key features of renal colic include:
Sudden Onset of Pain: The pain associated with renal colic typically comes on suddenly and is often severe. The pain may be intermittent and can fluctuate in intensity.
Location of Pain: The pain is usually felt in the lower back or side, below the ribs, and it can radiate to the lower abdomen and groin. The affected side is often tender to the touch.
Pain Characteristics: The pain is often described as sharp, stabbing, or cramping. It may come in waves and be associated with nausea and vomiting.
Urinary Symptoms: Renal colic can be accompanied by symptoms such as blood in the urine (hematuria), urgency to urinate, and frequent urination. However, these symptoms are not always present.
Painful Urination: Some individuals with kidney stones may experience pain or a burning sensation during urination.
Movement of Stones: The pain may change in intensity as the stone moves through the urinary tract. Relief may occur when the stone passes into the bladder.
If you suspect renal colic or have symptoms suggestive of a kidney stone, it is important to seek medical attention. Diagnosis may involve imaging studies such as a CT scan or ultrasound to visualize the presence, size, and location of the stone.
Treatment for renal colic often includes:
Pain Management: Medications such as nonsteroidal anti-inflammatory drugs (NSAIDs) or opioids may be prescribed to alleviate pain.
Hydration: Drinking plenty of water is recommended to help flush the stone out of the urinary tract.
Medical Expulsion Therapy: Some medications may be used to relax the muscles in the ureter, facilitating the passage of the stone.
Surgical Intervention: In cases where the stone is large or causing complications, surgical procedures such as lithotripsy or ureteroscopy may be considered.
- Ureters
– Enter bladder at the base
– Pass obliquely through the muscle
– Bladder contraction occludes the orifice, preventing reflux
– Reflux - Children
- May improve with age
- Renal damage correlates with frequency pyelonephritis
- More frequent with duplicated system
- Dx Voiding Cystourethrogram
(VCUG) - Urinary bladder
– Smooth muscle container
– All the action at the trigone
Describe the bladder trigone.
- Small triangular region
at the posterior bladder base - Orifices of ureters and urethra
– Just anterior to cervix in
women and rectosigmoid in men
– Prostate adjacent in men
– Diseases of these organs can result in obstruction of the tubes
How is urinary retention detected via Bladder US?
- In US of bladder measured by post void residuals
– Amount of urine left post void
– Normal < 50 ml*
– Abnormal > 200 ml* - US technique
– Bi-dimensional measurements@ - Easy (V = AP x Tv x Long)
- ~20% underestimation of volume^
– 3-dimensional scanners - BladderScan BVI 2500
- Special machine
- More accurate (3% underestimation)^
State causes of urinary retention.
- Causes*
– Obstruction - BPH
- Prostate cancer
- Cystocele / rectocele
- Urethral strictures
- Stones
– Neurologic disease
* Spinal cord / pelvic injury
* Stroke
* Multiple sclerosis / Guillain Barré
– Medications
– Recent abdominal surgery (temporary)
Describe the urethra in males and females.
Describe the 2 sphincters.
- Short tube in females
- Skene glands (mucous)
- Longer tube in males
– Proximal segment runs through prostate
– Distal end through the penis
– Surrounding glands
* Littre glands (periurethral, mucous)
* Prostate (seminal fluid)
* Seminal vesicles (seminal fluid)
* Cowper glands (pre-ejaculate)
- 2 sphincters
– Muscular control of urination
– Internal (bladder neck)
– External (membranous urethra)
