Weigert-Meyer rule
With complete ureteral duplication, the upper pole passes through the bladder wall to insert above and medial to the normally placed ureter draining the lower pole.
upper renal moiety ureter has ectopic insertion medial and inferior to the lower renal moiety ureter, and frequently ends in a ureterocele
lower renal moiety ureter has orthotopic insertion lateral and superior to the upper renal moiety ureter, and vesicoureteral reflux can occur
Ectopic ureter in females
The ectopic ureter may insert into the bladder, upper vagina, or urethra.
Ectopic ureter in males
It may insert into the lower bladder, prostatic urethra, seminal vesicles, or ejaculatory duct.
Ectopic ureterocele
The upper pole ureter acts as an ectopic ureterocele reflecting obstruction because of ectopic insertion.
Lower pole ureter
Inserts in the normal location in the bladder trigone and is subject to reflux.
Extrarenal Pelvis
The position of the left renal pelvis outside of the renal sinus enables the pelvis to distend with urine and to be larger than the normal right renal pelvis.
Complications of complete duplication
Include urinary tract infection, vesicoureteral reflux, and obstruction of the lower pole system.
Ureteral narrowing points
Three main points of ureteral narrowing are (a) the ureteropelvic junction (UPJ), (b) the site at which the ureter crosses the pelvic brim, and (c) the ureterovesical junction (UVJ).
Congenital Anomalies
Ureteral duplication occurs in 1% to 2% of the population.
Unilateral duplication
Is six times more common than bilateral duplication.
Bifid renal pelvis
Occurs in 10% of the population and has no pathologic consequences.
Duplicated ureters
Tend to meander and twist about each other as they course to the bladder.
What does UTD stand for in the context of urinary tract classification?
Urinary Tract Dilatation
UTD classification system is used to assess urinary tract dilation in fetuses.
What is the classification for minimal dilation of the renal pelvis in UTD?
- 4 to <7 mm (16-27 wks GA)
- 7 to <10 mm (28 wks GA or older)
Minimal dilation indicates slight enlargement of the renal pelvis.
What indicates moderate to severe dilation of the renal pelvis in UTD?
- > 7 mm (16-27 wks GA)
- > 10 mm (28 wks GA or older)
This classification suggests more significant urinary tract dilation.
What are some abnormal findings associated with UTD?
- Parenchyma abnormal: thinning, cysts, or echogenic
- Unexplained oligohydramnios
- Abnormal ureter
- Abnormal urinary bladder
These findings can indicate complications related to urinary tract dilation.
When should follow-up for UTD be performed?
- 1 to 6 months later
- Sooner for suspected obstructive uropathies
Follow-up is crucial for monitoring conditions like posterior urethral valves.
True or false: Counseling patients about antenatally detected pyelectasis is based on a large number of studies reviewing outcomes.
TRUE
A meta-analysis combined findings from 1678 cases of antenatal hydronephrosis from 17 independent studies.
What is STAGE I of tumor classification?
- A completely resected tumor limited to the kidney with an intact capsule
- No biopsy or rupture of tumor before removal
- No involvement of vessels or renal sinuses
- No tumor at or beyond the margins of resection
- Regional lymph nodes are negative for tumor
This stage indicates a localized tumor without any complications.
What findings are associated with STAGE II of tumor classification?
- A completely resected tumor
- No tumor at or beyond the margins of resection
- Regional lymph nodes are negative for tumor
- One or more of the following findings:
- Penetration of the renal capsule
- Invasion of vasculature extending beyond the renal parenchyma
This stage indicates more advanced local involvement compared to Stage I.
What defines STAGE III of tumor classification?
- Residual tumor is present after surgery, confined to the abdomen
- One or more regional lymph nodes are positive for tumor
- The tumor is implanted on or penetrating through the peritoneum
- The presence of gross unresected tumor or tumor at the margin of resection
- Any tumor spillage occurring before or during surgery, including biopsy
- The tumor was removed in more than one piece
This stage indicates significant progression and complications post-surgery.
What characterizes STAGE IV of tumor classification?
- The presence of hematogenous metastasis (e.g., lung, liver, bone, or brain)
- The presence of lymph node metastasis outside the abdomen and pelvis
This stage indicates widespread disease with distant metastasis.
What is the definition of STAGE V in tumor classification?
Wilms tumor in both kidneys
This stage indicates bilateral involvement of the kidneys.
What is the first grade of the Renal Injury Scale according to the American Association for the Surgery of Trauma (AAST)?
Renal contusion, small nonexpanding subcapsular hematoma
This grade indicates a minor injury to the kidney.
