Urinary - Calculi & Obstruction Flashcards
-out pouching of bladder wall
-weakness in bladder wall
-can become filled with urine (stasis) or debris (calculi) which causes infection
-more common in males
Bladder diverticulum
Infection of diverticulum (out pouching)
Diverticulitis
-most commonly form in the kidney
-asymptomatic until they lodge in the ureter and cause partial obstruction
-extreme pain that radiates from kidney to groin
Calculi (urinary)
What are some causes of calculi?
-often an underlying metabolic abnormality (ex. Hypercalcemia)
-urinary stasis and infection
T/F
>80% of symptomatic stones contain enough calcium to be radiopaque and detectable on plain abdominal radiographs
True
*some are radiolucent (contain no calcium)
T/F
Plain X-rays miss approx. 34% of stones because of their size, location or because they are obscured by bowel or bone
True
How is radiography useful for calculi?
KUB - radiopaque calcium renal stones
CT - location of stone
IVU - non calcium stones cause filling defects
US - an echogenic region with acoustic shadowing
What are some treatment options for calculi?
-medications to dissolve
-lithotripsy to break up
-cystoscopy for retrieval or laser destruction
-surgery
-completely fill renal pelvis
-obstructs the flow of urine
-nephrostomy tube needed (inserted through skin to drain backed up kidney)
Staghorn calculus
-small blood clots in a vein that calcify over time
-usually asymptomatic
-mimic calculi on xray
-often found in lower pelvis; below a line joining the ischial spines
Phleboliths
*different because uretral stones are situated medially above the ASIS
-a cystic dilation of the distal ureter near its insertion into the bladder
Ureterocele
How does a ureterocele appear in adults and children?
Adults
-stenosis of the ureteal office with varying degrees of dilation of the proximal ureter
-stenosis leads to prolapse of the distal ureter into the bladder and dilation of the lumen of the prolapsed segment
Children (ectopic ureteroceles)
-most are associated with uretral duplication (in 80% of cases)
How does a ureterocele appear on an ultrasound?
Round cyst like structure within the bladder
T/F
If a ureterocele is filled, the lesion appears round or oval density surrounding by a thin radiolucent halo representing the wall of the prolapsed ureter and the mucosa of the bladder
True
IVU
T/F
If the ureteocele is not filled with contrast material, it appears as a radiolucent mass within the opacitied bladder in the region of the uretral orifice
True
IVU
What are the causes of obstruction in adults and children?
Adults
Urinary calculi, pelvic tumors, urethral strictures, enlargement of prostate gland
Children
Congenital malformations (uretropelvic junction narrowing, ureterocele….)
What are common sites of obstruction?
Ureteropelvic and ureterovesical junctions, bladder neck, urethral meatus
What do blockages above the bladder cause?
-unilateral dilation of the ureter (hydroureter)
-renal pelvicalyceal system (hydronephrosis)
T/F
If lesion is at or below the bladder, bilateral involvement is the rule
-obstruction can lead to renal colic
True
Pain associated with the passage of a renal calculus through the ureter
-intense pain along side of body, lower abdomen
-pain spread to back/groin
-nausea vomitting
-pain comes in waves that last 20-60 minutes
Renal colic
What imaging is used to identify obstructions?
CT
IVU
US
SEE SLIDE
What is the treatment for obstruction?
-decompression of urinary tract
-percutaneus nephrostomy to demonstrate obstruction and provide drainage
Swelling of the pelvicalyceal system due to a backup of urine
Hydronephrosis
What are the causes of hydronephrosis?
-nephrolithiasis (kidney stone)
-obstructive uropathy (kidney disease)
-extrinsic and intrinsic obstruction of the ureter (tumor)
-vesicoureteral reflux
-pregnancy
What are the common manifestations of hydronephrosis?
-flank pain
-abdominal mass
-nausea/vomitting
-UTI
-fever
-painful urination
-frequency and urgency
-asymptomatic
What are the radiographic procedures used for hydronephrosis?
-non contrast CT
-contrast enhanced CT
-ante grade pyelography
-US
Catheter is placed percutaneously into dilated collecting system under fluoroscopic guidance and radiopaque contrast is injected for visualization of obstruction
Antegrade pyelography
What are common treatments for hydronephrosis?
Depends on cause:
-urethral stent - tube allows ureter to drain into bladder
-nephrostomy tube - allows blocked urine to drain from kidney through the back
-antibiotics
Unilateral dilation of the ureter due to backup of urine
Hydroureter
T/F
In children, most ureterocele are associated with urethral duplication (80% of cases)
True
Where ureter joins the bladder
Ureterovesical (UV) junction
Where ureter joins kidney
Ureteropelvic junction
