renal sinus

Renal SinusRenal Sinus

Jud Gash, MDJud Gash, MD

Renal SinusRenal Sinus

Renal Sinus - area Renal Sinus - area within invaginated within invaginated kidneykidney

Renal hilum – area Renal hilum – area that connects renal that connects renal sinus to sinus to perinephric space perinephric space (retroperitoneum)(retroperitoneum)

Renal SinusRenal Sinus ContentsContents

Collecting systemCollecting system Arteries and veinsArteries and veins Lymphatics and nervesLymphatics and nerves Fat (and fibrous tissue)Fat (and fibrous tissue)

Tip: Consider the Tip: Consider the above contents to form above contents to form differential of Pathologydifferential of Pathology

Also abnormalities via Also abnormalities via extension from kidney extension from kidney (RCC) or retroperitoneum (RCC) or retroperitoneum (lymphoma)(lymphoma)

Normal Renal Sinus - Normal Renal Sinus - UltrasoundUltrasound

Hyperechoic Hyperechoic central area central area Aka…Aka…

central echo central echo complexcomplex

Represents Represents fat within fat within renal sinusrenal sinus

Normal Renal Sinus - Normal Renal Sinus - UltrasoundUltrasound

As As technology/rtechnology/resolution esolution improve, improve, visualization visualization of collecting of collecting system and system and vessels vessels become become more more commoncommon

Normal Renal Sinus – Normal Renal Sinus – CT/MRICT/MRI

FatFat VesselsVessels CollectinCollectin

g Systemg System

Normal Renal Sinus – Normal Renal Sinus – CT/MRICT/MRI

Tip: Careful Tip: Careful narrow narrow windowing windowing allows distinction allows distinction of collecting of collecting system and system and vessels on vessels on noncon CT noncon CT Important for Important for

detection of early detection of early hydronephrosis hydronephrosis or hydrocalyx!or hydrocalyx!

Standard soft tissue window: vessels

and collecting system similar

Narrow window

differentiates vessels

and collecting

system

Pathology of Renal SinusPathology of Renal Sinus

Non-Neoplastic Lesions of the Renal Non-Neoplastic Lesions of the Renal SinusSinus

Hydronephrosis and Stones (discussed elsewhere)Hydronephrosis and Stones (discussed elsewhere) Renal Sinus LipomatosisRenal Sinus Lipomatosis Renal Sinus CystsRenal Sinus Cysts Vascular LesionsVascular Lesions Other Rare LesionsOther Rare Lesions

Neoplastic Lesions of the Renal SinusNeoplastic Lesions of the Renal Sinus From collecting systemFrom collecting system From mesenchymeFrom mesenchyme From KidneyFrom Kidney From perinephric spaceFrom perinephric space

Renal Sinus LipomatosisRenal Sinus Lipomatosis Renal sinus Renal sinus

lipomatosislipomatosis Condition of Condition of

increased increased sinus fat sinus fat

Almost Almost always always incidentalincidental

Renal sinus Renal sinus fat increases fat increases with age (and with age (and with renal with renal atrophy and atrophy and with steroids)with steroids)

Importance is Importance is to not mistake to not mistake for pathologyfor pathology

Renal Replacement Renal Replacement Lipomatosis (RRL)Lipomatosis (RRL)

Marked fatty Marked fatty proliferation proliferation and and replacement of replacement of renal renal parenchyma parenchyma

Stone disease Stone disease and chronic and chronic inflammationinflammation

UnilateralUnilateral Can mimick Can mimick

fatty tumor fatty tumor (AML, (AML, liposarcoma)liposarcoma)

Overlaps XGPOverlaps XGP

JUM September 1, 2008 vol. 27 no. 9 1393-1395

Renal Replacement Renal Replacement LipomatosisLipomatosis

Renal Replacement Renal Replacement LipomatosisLipomatosis

Another CaseAnother Case Point: Widely Point: Widely

dispersed dispersed renal calculi renal calculi ie…”Explodeie…”Exploded Calculi” d Calculi” deserve CT.deserve CT.

In fact, any In fact, any signficant signficant renal stone renal stone burden need burden need CTCT

Ind J Radiol Imag 2002 12:1:117-119

RRL vs XGPRRL vs XGP

Renal Sinus CystsRenal Sinus Cysts Two Types:Two Types:

Parapelvic cyst (Gash Proposal: “Simple renal Parapelvic cyst (Gash Proposal: “Simple renal parenchymal cyst that extends into the renal parenchymal cyst that extends into the renal sinus”)sinus”)

simple cyst arising from renal parenchyma and simple cyst arising from renal parenchyma and protruding into sinusprotruding into sinus

Imaging same as simple cystImaging same as simple cyst Peripelvic cyst (Gash Proposal: “Renal Sinus Peripelvic cyst (Gash Proposal: “Renal Sinus

Lymphatic Cysts)Lymphatic Cysts) Extraparenchymal collection of small cysts arising Extraparenchymal collection of small cysts arising

within the sinuswithin the sinus Often bilateralOften bilateral Probably of lymphatic in originProbably of lymphatic in origin Usually asymptomatic; but can rarely can cause Usually asymptomatic; but can rarely can cause

obstructionobstruction MimicsMimics

Hydronephrosis on US/CT/MRIHydronephrosis on US/CT/MRI

Simple Renal Cysts Simple Renal Cysts extending into renal pelvis extending into renal pelvis

(ie parapelvic)(ie parapelvic)

Renal Sinus Lymphatics Renal Sinus Lymphatics CystsCysts

(peripelvic) - Bilateral(peripelvic) - Bilateral


(peripelvic) - Unilateral(peripelvic) - Unilateral

www.dcaimaging.org


(peripelvic) vs Hydro(peripelvic) vs Hydro Sometimes cant be Sometimes cant be

sure on Ultrasound sure on Ultrasound or noncontrast or noncontrast CT/MRI and may CT/MRI and may require delayed require delayed postcontrast postcontrast imagingimaging

Renal Renal LymphangiomatosisLymphangiomatosis

((Big brother of peripelvic Big brother of peripelvic cysts)cysts)

Gorantla R, Yalapati A, Dev B, Joseph S. Case report: Perinephric lymphangiomatosis. Indian J Radiol Imaging 2010;20:224-

Renal Renal LymphangiomatosisLymphangiomatosis

Rare and BenignRare and Benign Cystic dilatation of intrarenal, peripelvic Cystic dilatation of intrarenal, peripelvic

and perirenal lymphaticsand perirenal lymphatics Due to obstructed lymphatic drainageDue to obstructed lymphatic drainage

Asymptomatic; rarely flank pain, htn, Asymptomatic; rarely flank pain, htn, hematuriahematuria

Imaging shows cystic (and septated) Imaging shows cystic (and septated) perirenal and renal sinus anechoic/water perirenal and renal sinus anechoic/water density/intensity collections in otherwise density/intensity collections in otherwise normal kidneysnormal kidneys

Dx – aspiration of chyle rich in lymphocytesDx – aspiration of chyle rich in lymphocytes

Renal Sinus Vascular Renal Sinus Vascular LesionsLesions

Renal Artery AneurysmRenal Artery Aneurysm Renal AVMRenal AVM Renal Vein VarixRenal Vein Varix

Renal Artery AneurysmRenal Artery Aneurysm Renal Artery Renal Artery

AneurysmAneurysm Dx – when Dx – when

diameter >2X diameter >2X normal diameternormal diameter

Usually Usually Atherosclerotic Atherosclerotic (smaller due to (smaller due to vasculitis)vasculitis)

Frequently Frequently calcifiedcalcified

Differentiation Differentiation from stone key from stone key before ESWLbefore ESWL

Can rupture Can rupture (embolize)(embolize)

Esp in Esp in pregnancypregnancy

May be followed May be followed or treatedor treated

Radiographics. 2000;20:1321-1340

Renal AVMRenal AVM Direct arterial to Direct arterial to

venous communicationvenous communication Two TypesTwo Types

CongenitalCongenital AcquiredAcquired

Most commonMost common Usually after bx, Usually after bx,

surgery, traumasurgery, trauma Usually asymptomaticUsually asymptomatic

Rarely hematuria, pain, Rarely hematuria, pain, HTN or ruptureHTN or rupture

CT depends on timing, CT depends on timing, but tangle of but tangle of distended vessels with distended vessels with larger early draining larger early draining veinsveins


Rare Lesions of the Rare Lesions of the Renal SinusRenal Sinus

2 Cases of 2 Cases of CastlemanCastleman’’s s DiseaseDisease

Other rare Other rare lesions lesions including including tumefactive tumefactive fungal fungal infection, infection, urinomas and urinomas and hematomas, hematomas, etcetc

AJR 2003; 181:1037-1040

Tumorous Lesions of the Tumorous Lesions of the Renal SinusRenal Sinus

TumorsTumors From collecting systemFrom collecting system From mesenchymeFrom mesenchyme From KidneyFrom Kidney From perinephric spaceFrom perinephric space

Tumors from the Collecting Tumors from the Collecting SystemSystem

Tumor arises from the pelvicaliceal Tumor arises from the pelvicaliceal collecting system and secondarily collecting system and secondarily extends to the renal sinus and/or extends to the renal sinus and/or kidneykidney

Cell TypesCell Types Urothelial Carcinoma (UC) (90%)Urothelial Carcinoma (UC) (90%) SCC (9%)SCC (9%) AdenocarcinomaAdenocarcinoma

Presents with hematuria, obstruction, Presents with hematuria, obstruction, or incidentallyor incidentally


Imaging - depends on stage Imaging - depends on stage Early lesionsEarly lesions

On CT/CTU (MRI) – On CT/CTU (MRI) – soft tissue filling defectsoft tissue filling defect Phantom calyxPhantom calyx Moth eaten calyxMoth eaten calyx

On US – usually not seenOn US – usually not seen

Early Lesions – Lessons Early Lesions – Lessons from IVPfrom IVP

Filling DefectFilling Defect Phantom CalyxPhantom Calyx Moth Eaten CalyxMoth Eaten Calyx


Early Lesion - CTEarly Lesion - CT Filling Defect on CTFilling Defect on CT

TumorTumor ClotClot Fungus BallFungus Ball Sloughed PapillaSloughed Papilla (NOT Stone x iodinovir)(NOT Stone x iodinovir)

ThoughtsThoughts Tumor most likelyTumor most likely

Clot should be hyperdense Clot should be hyperdense and not enhanceand not enhance

Fungus Ball clinically Fungus Ball clinically suspected and not enhancesuspected and not enhance

Sloughed papilla should not Sloughed papilla should not enhance and see changes of enhance and see changes of calyx of papillary necrosiscalyx of papillary necrosis

Cytology, ureteroscopy and Cytology, ureteroscopy and follow up CT urogram are follow up CT urogram are management plansmanagement plans

RadioGraphics 2004;24:S35-S54


Late LesionsLate Lesions US US

““fragmentatifragmentationon”” of of central echo central echo complexcomplex

CT (MRI)CT (MRI) Soft tissue Soft tissue

mass that mass that invades invades sinus and sinus and kidneykidney

Missed Lesion – non-CTMissed Lesion – non-CT

Careful on Careful on noncontrast noncontrast stone studiesstone studies


2 Issues about renal 2 Issues about renal pelvic UCpelvic UC

Minor issue – Differentiation from Minor issue – Differentiation from SCCSCC

Major issue– Differentiation from Major issue– Differentiation from RCCRCC

UC vs SCCUC vs SCC

Usually Usually cannot tell cannot tell differencedifference Stones Stones

suggest SCCAsuggest SCCA But, UC much But, UC much

more commonmore common

UC vs RCCUC vs RCC Can be hard to Can be hard to

distinguishdistinguish UC can extend into UC can extend into

kidneykidney RCC can extend into RCC can extend into

sinussinus UCUC

More centralMore central Infiltrates, rather than Infiltrates, rather than

expands, kidneyexpands, kidney Different ManagementDifferent Management

UC – UC – nephroureterectomy & nephroureterectomy & cuffcuff

RCC – radical RCC – radical nephrectomynephrectomy

May need tissue to tell May need tissue to tell (at surgery or with (at surgery or with ureteroscopy)ureteroscopy)


Sinus Tumors From Sinus Tumors From MesenchymeMesenchyme

All rareAll rare BenignBenign

hemangioma, hemangioma, fibroma, fibroma, leiomyoma, leiomyoma, angiomyolipoma, angiomyolipoma, neurogenic neurogenic tumor, and tumor, and teratomateratoma

MalignantMalignant leiomyosarcoma, leiomyosarcoma,

fibrosarcoma, fibrosarcoma, liposarcoma, liposarcoma, hemangiopericytohemangiopericytoma, and ma, and malignant fibrous malignant fibrous histiocytoma histiocytoma

Appear as Appear as nonspecific, well nonspecific, well circumscribed circumscribed sinus soft tissue sinus soft tissue massmass

Sinus Tumors from Sinus Tumors from KidneyKidney

All renal All renal tumors can tumors can invade pelvisinvade pelvis

RCC (as RCC (as before)before)

Multilocular Multilocular Cystic Cystic NephromaNephroma

Classically Classically herniates herniates into sinusinto sinus

Sinus Tumors from Sinus Tumors from RetroperitoneumRetroperitoneum

All All retropertioneretropertioneal tumors al tumors can extend to can extend to renal sinusrenal sinus

But, only But, only lymphoma lymphoma does this does this with any with any frequencyfrequency


renal sinus

Health & Medicine