Ureteral obstruction Flashcards
Name ddx for proximal hydronephrosis?
Acquired:
Extrinsic: ureteral stone, peripelvic cyst or mass
Intrinsic: benign fibroepithelial polyp, urothelial malignancy, post-inflammatory or post-operative scarring or ischemia
Congenital: retrocaval ureter (S shaped RGP), aperistaltic ureteral segment, mucosal kink/valve/adhesion
Describe dismembered ureteroplasty with transposition of ureter:
- Foley
- Lateral decubitus left side down (if doing retrocaval ureter)
- Port placement like kidney
- Transpertioneal, mobilize bowel
- mobilize proximal ureter/UPJ
- Divide ureter above and below IVC, leaving enough redundancy to perform UU
- Reconstruct ureter anterior to IVC, spatulate +/- graft, anastomosis watertight, 4-0 Vicryl, stent
- Drain
- Close
Pathophysiology of retrocaval ureter?
failure of supra-cardinal vein to develop into IVC below kidney possibly due to persistent of sub-cardinal vein or persistent of posterior cardinal vein as infrarenal IVC
1/1100, males, usually right, in 20s-30s
presenting sxs: abdominal/flank pain, recurrent UTI, HTN
What is differential of bilateral ureteral obstruction, not secondary to stones or retention?
lymphoma
metastatic dz (unknown primary including testis)
primary RP mass
RP fibrosis (proximal hydro, medial deviation, extrinsic compression of fibrotic plaque)
What lab studies are abnormal in retroperitoneal fibrosis? What is first step after b/l stents and monitoring for POD?
ESR
gamma globulin levels (IgG4)
First step: CT guided needle bx
Tx options for RP fibrosis?
- Glucocorticoids: most effective when labs abnormal, 20-60 mg daily x 6-8 weeks, then taper up to 24 mo, may be combined with other immunosuppressants, combine with H2 blockers and Ca
- Tamoxifen: anti-estrogen, in desmoid tumors and invasive fibrous tissue, 20 mg daily x 12 mo
- If no improvement, resection, ureterolysis, if not possible can do reimplant, psoas hitch, boari flap, ileal interposition, or autotxp
Causes of RP fibrosis?
- Drugs: beta blockers, methyldopa, hydralazine, ergotamine alkaloids (LSD, methysergide), haloperidol, amphetamines, phenacetin, risperidone
- Infection: syphilis, Tb, gonorrhea, chronic UTI
- Chemicals: asbestos, talcum powder, avitene
- Malignancy: primary, chancroid, mets RP tumors
- Idiopathic
What is a surgical approach for b/l RP fibrosis with extrinsic compression of ureter?
bilateral ureterolysis
Robotic/lap or open
take biopsies with intraop frozen (demoplastic fibrous tissue)
ID ureter over iliac (usually less involved there)
incise posterior peritoneum
DISSECTION BEGINS over distal, non-dilated ureter and proceed proximally (avoid injury to dilated segment)
may consider omental wrap (mobilize omentum from transverse colon (divide and ligate short gastric vessels to swing omentum laterally)
Describe and endopyelotomy:
Antegrade or retrograde
Make longitudinal incision posteriolaterally at UPJ (avoid injury of possible crossing vessel) until you see peri-ureteral fat. Leave stent. Use safety wire across UPJ.
What are options for failed pyeloplasty and persistent UPJO?
- Salvage endopyelotomy
- Re-do pyeloplasty
- Ureterocalicostomy (if renal pelvis small and primary anastomosis not possible
- Ileal ureter (long stricture, must have decent GFR, Cr < 2)
- Autotransplant (if no other tx feasible)
- Nephrectomy (< 10% function, normal contralateral, if further repair extremely complicated, short life expectancy, comorbid conditions)
Describe ureterocalicostomy:
- Amputate lower pole of kidney
- Mobilize lower poly calyx
- Excise strictured ureter
- Spatulate ureter
- Obtain watertight tension free anastomosis of ureter and calyx
- Insert stent
- Wrap omentum, peritoneum, or peri-renal fat around anastomosis
- Place drain
What does Tb look like in ureter? How do you treat?
Urine culture for AFB: + mycobacterium Tb
hydronephrosis with calcification along the ureter/narrowing/stricture
also assess kidney (tends to have trickle down effect, tend to have infundibular stenosis and papillary necrosis)
Treatment: PCN or stent, treat Tb (INH + Pyridoxine, Rifampin, Pyrazinamide? (resistance), Ethambutol)
*meds have high urinary concentrations
After period of recovery consider URS + bx (fibrosis)
What are options for mgmt of distal ureteral strictures?
- Endourologic: stent, balloon dilation (antegrade/retrograde), endoureterotomy
- Surgical recon: UU (short defect upper/mid) , transUU, reimplant (best for distal +/- Boari and/or psoas hitch), ileal ureter (very long, other failures, keep in mind metabolic concerns), autotxp
IMPORTANT: if considering Boari or Psoas Hitch must evaluate bladder fxn and capacity, BOO, and NGB
Describe a ureteroneocystostomy (reimplant) with Boari flap:
- Foley
- Access(open or robot, supine)
- ID ureter crossing iliac vessels
- Preserve adventitia to max post-op blood supply
- can perform flex URS to help ID distal extent of stricture
- transect at level of obstruction, mobilize proximally
- Perform reimplant only if tension-free, if not boari +/- psoas hitch
- Divide contralateral blader pedicle for improved mobility
- Posterolateral bladder flap outlined based on identification of ipsilateral superior vesicle artery
- Distal end of flap should be pexed to psoas minor tendon or psoas major muscle with absorbable suture
- Distal ureter should be spatulated and anastomosis performed
- Bladder flap tubularized and closed
- Leave JJ stent in place prior to closing flap
- Place drain
- Leave Foley cath in place
