CT Urography-MH

Mindy M. Horrow, MD,FACR, FSRU

Director of Body Imaging AEMC

Professor of Radiology

TJU Medical School

January, 2012

CTUrography

Technique

No oral contrast

Low dose non contrast of kidneys through bladder

125 cc IV contrast, image kidneys duringnephrographic phase (100-110 sec)

300 cc IV fluid, 6-8 minutes, roll patient 360

Re-scout

Image kidneys through bladder with 2D and 3Dreconstructions, zoom and view at wide windowsettings

Report

Full description of kidneys, including renal lengths,comment on contour, symmetry of collecting systems,displacement, etc.

Function (symmetry of nephrograms and pyelograms)

Comment about degree of collecting system, ureteral andbladder opacification, search carefully for filling defectsand irregularities

Other findings

Normal Medullary Blush

Delayed right nephrogram

Delayed right pyelogramwith perinephric fluid

Acute high grade ureteral obstruction withforniceal rupture, secondary to calculus

Moderate caliectasis, minimalfunctional obstruction

Minimal dilatation secondaryto crossing vessel

Medullary Sponge Kidney

Definition: Cystic dilatation of collecting tubules

0.5% incidence on IVU

Etiology: unknown

Range of findings from mild dilatation tubules in102 pyramids (renal tubular ectasia) thoughworsening dilatation to gross deformity ofcalyces with cysts and cyst like cavitiesextending through pyramids

Typical rounded and linear calcifications

Medullary Sponge Kidney

Normal Retrograde Urogram

Papillary Necrosis

Ischemia and necrosis in medullary portion of kidneyleads to inability to concentrate urine and polyuria,and decreased GFR

Sloughed papilla can lead to infection and obstruction

Two Types

–Medullary: intact fornices, discreet necrotic areas inpapillae

–Papillary: calyceal fornices and entire papillary surfacedestroyed leading to dilated, blunted calyces

Papillary Necrosis

Pyelonephritis

Obstruction

Sickle Cell Disease

Tuberculosis

Cirrhosis

Analgesics

Renal vein thombosis, renal tx rejection, radiation

Diabetes, dehydration

Systemic vasculitis

Papillary Necrosis with cortical scarring

Abnormally shaped, clubbed calyx

Sloughed papilla from papillary necrosis

Another example of papillarynecrosis with sloughed papillae

Large simple cyst causingsmooth impression on calyces

Parapelvic Cysts, Accessory Calyx

Parapelvic Cysts

Not true renal cysts, may be lymphatic in origin ordevelop from embryologic rests

Typically asymptomatic, but can be associated withhypertension, hematuria or hydronephrosis

May be difficult to distinguish from hydronephrosisor dilated renal pelvis on ultrasound or non-contrastCT

Renal Varix

Oncocytoma

Oncocytomas

Benign tumors, no metastatic potential

Most common in middle to older agedmen

Homogeneous enhancement on CT

Pseudocapsule, central scar in biggerlesions

“Spoke wheel” arteriographic pattern

Renal Cell Carcinoma

Hemorrhage and Amputated calyx

Calyceal Diverticulum

Urine containing cavity in renal parenchymacommunicating with collecting system throughnarrow channel

Two types

–Related to minor calyx in upper pole

–Communicates with renal pelvis or major central calyx

Usually asymptomatic, occasionally pain, UTI

Mobile calculi or milk of calcium are characteristic

US: simple cyst or cyst with calcification

BJ Radiology 2001;74:595

38 year old

SimpleUreterocele

Ultrasound appearance ofsimple ureterocele

Routine positive stone search study

Simple ureterocele only visualized with CTU

Simple ureterocele with calculus

Simple Ureterocele with calculus

Prolapse of mucosa of terminal segment of ureter throughureterovesical orifice into bladder

Hyperplastic response to some degree of meatalobstruction

Since there is no muscle support of double mucosal wallsof prolapsed segment, it dilates, fills with urine andprotrudes into bladder

Simple ureterocele: normal position ureteral orifice,obstruction can be congenital or acquired secondary toinflammation

Ectopic ureterocele: protrusion of dilated submucosalportion of ectopic ureter, associated with duplicatedcollecting systems, from the upper pole moiety, insertsinferior to normal orifice

Radiographics 2002;22:1139

Pseudoureterocele

Cobra-head shaped distal ureter withincomplete distal ureteral obstruction usuallydue to tumor or calculus.

Lucency surrounding it is thicker than aureterocele and is poorly defined and possiblyirregular.

More likely than a ureterocele when there isasymmetry of dilated ureteral lumen,obstruction of upper tract and evidence of anacquired cause such as a calculus or abnormalvesical mucosal pattern

Radiology 2002;225:781

Papillary urothelial cell CA of renal pelvis

(originally interpreted as a blood clot in the renal pelvis)

Hematuria

Non con

Urothelial malignancy distal ureter

Bladder images from CT Urogram

Multifocal urothelial tumors

Patterns of UrothelialMalignancy in Renal Pelvis

Single or multiple irregular filling defects

Filling defects in dilated calyces

Calyceal amputation

Decreased or absent excretion withoutrenal enlargement secondary tolongstanding obstruction with atropy

Hydronephrosis with renal enlargement

Circumcaval (Retrocaval)Ureter

Circumcaval Ureter

Circumcaval Ureter

IVC formed at 6-8 weeks as composite of 3paired sets of embryonic veins

Right supracardinal vein fails to form and rightposterior cardinal vein persists

Proximal right ureter passes posterior to IVC,emerges to right of aorta, eventually lyinganterior to right iliac vessels

May lead to obstruction and infections

Radiographics 2000;20:639

Grading of Cystoceles

1.Mild bladder descent into vagina

2. Bladder descends to vaginal orifice

3. Bladder protrudes through vagina

“Christmas Tree” Bladder

Thickened wall

Pear Shape

Multiple diverticula

Megacalyces

Other Ureteral Abnormalities

Hematuria

Ureteral Notchingsecondary to retroperitoneal varices fromhighly vascular renal cell carcinoma

Causes of Ureteral Notching

Arterial: renal/iliac/aortic aneurysm

Venous: normal or enlarged gonadal veins, rightovarian vein syndrome, varicocele and varices ofbroad ligament, occlusion IVC below renal veins bytumor, RPF, clot, surgery; occlusion IVC aboverenal veins by thrombus or tumor; occlusion SVCby tumor, portal hypertension

Kawashima, etal. Radiographics 2000;20,1321

1.3.46.670589.28.265407955701.2011032415372046732022112210.jpg

Urinary Tract Tuberculosis

Neo-ureter

39 year old woman with historyof breast cancer

Sagittal R adnexa

Pelvic endometriosiscausing bilateralhydroureteronephrosis

Deep Endometriosis

Defined as endometriosis penetratingretroperitoneal space or wall of pelvicorgans to at least 5mm

involves retroperitoneum and recto-vaginal septum> vagina> bowel>bladder> ureter

Causes significant pain, urinary andbowel symptoms and infertility

Deep Endometriosis

Histology: fibromuscular hyperplasiasurrounds foci of endometriosis infiltratingadjacent tissues, forming solid nodules

Involvement of ureter causes hydroureter andhydronephrosis, often isidious onset

Usually extrinsic involvement of distal 1/3 ofureter, occasionally invasive

Bladder involvement more common, usually as2-4 cm mass in dome with other disease

Bazet. Radiology 2004;232:379

Del Frate. Radiographics 2006;26:1705

69 year old with history of prostate carcinoma

Benign Ureteral Stricture

Causes: surgery, trauma, radiationtherapy, infection, calculous disease,retroperitoneal fibrosis

73 year old

Retroperitoneal Fibrosis

Inflammatory aneurysm causing medial deviation of ureters

Hematuria in 68 year old

Retroperitoneal Fibrosis

Typically peri-aortic distribution

May encase ureters, extend into renalhilum.

Localized peri-ureteral fibrosis may bedue to chronic indwelling ureteralstent, sarcoidosis, malignancy

62 year old man

6-7-05 post stent 2 w ureteral stent.jpg

7-6-06

Retroperitoneal fibrosis secondary to inflammatory aneurysm

Treated with vascular and ureteral stents

Two different patients

Pseudodiverticulosis

Definition: < 5mm sized out pouchingsof hyperplastic transitional epitheliuminto subepithelial connective tissuewith associated chronic inflammatorychanges

Do not penetrate muscular wall and areNOT true diverticula