DM

Diagnostic Medical ImagingDonald Ly, Vincent Spano and Christian '9aD der Pol, chapter editors Christophel' Kitamura and Michelle Lam, associate editors Janine Hutson, EBM editor Dr. TaeBoog Chong, Dr. Marc Freeman, Dr. Nasir Jaffer, Dr. Vlkram Prabhudesai and Dr. Eugene Yu, staff editorsImaging Modalities ...................... 2 X-Ray Imaging Ultrasound (U/S) Magnetic Resonance Imaging (MRI) Positron Emission Tomography Scans (PET) Contrast Enhancement Chest Imaging .......................... 4 Chest X-Ray (CXR) Computed Tomography (CT) Chest lung Abnormalities Pulmonary Vascular Abnormalities Pleural Abnormalities Mediastinal Abnormalities Tubes, lines, and Catheters Gastrointestinal (GI) Tract . . 11 Modalities Approach to Abdominal X-Ray (AXR) Approach to Abdominal Computed Tomography (CT) Contrast Studies Specific Visceral Organ Imaging "itis" Imaging Angiography of Gl Tract Genitourinary System ................... 15 Modalities Gynecological Imaging Selected Pathology Neuroradiology . . . . . . . . . . . . . . . . . . . . . . . . 17 Modalities Approach to CT Head Selected Pathology Musculoskeletal System (MSK) . 20 Modalities Approach to Interpretation of Bone X-Rays Trauma Arthritis Bone Tumour Infection Metabolic Bone Disease Nuclear Medicine ....................... 25 Thyroid Respiratory Cardiac Bone Abdomen Inflammation and Infection Brain lnterventional Radiology ................. 27 Vascular Procedures Nonvascular Interventions Women's Imaging ...................... 29 Modalities Breast Imaging Reporting Breast Findings References . . . . . . . . . . . . . . . . . . . . . . . . . . . . 32

Please see the Essentials of Medical Imaging software for illustration& of the content in this chapter Toronto Notes 2011 Diagnostic Medical Imaging DMI

DM2 Diagnostic Medic:allmaging

Imaging Modalities

Toronto Notes 2011

Imaging ModalitiesX-Ray ImagingDlapolllc ,....lc.. Uposartll(in dulls)

... .,.., 1211111

D - hill

&jlillllll . . . . . .

Pnd If Nlllnl

llilllian''

lldrpnll

x-rays, or Roentgen rays, are a form of electromagnetic energy of short wavelength as x-ray photons traverse matter, they can be absorbed (process known as "attenuation&) and/or scattered the density of a structure determines its ability to attenuate or "weaken& the x-ray beam air < fat < water < bone < metal structures that have high attenuation, e.g. bone, appear white on the resulting images two broad categories: plain films and computed tomography (CT)

Plain Films x-rays pass through the patient and interact with a detection device to produce a 2-dimensional projection image structures closer to the film appear sharper and less magnified contraindications: pregnancy (relative) advantages: inexpensive, non-invasive, readily available di1advantages: radiation exposure, generally poor at distinguishing soft tissues

10 Thcnck:'line 50 75 Urrillr11Jinl Dlest PA film) I

c.Mail.SklJ

5

12d111 3WIIb 2dlys Idly 7WIIb10Mib

lateral decubitus Position

1 o

"-

Figura 1. CXR Viaws

'IbroDlo Nota 2011

Chen ImagiDg

Diagnostic Medkal I:maginB DMS

.,u

legendlllrtic arch IIGfb)iJulmanary window llllarior 8DpiiC8 carill c:lavicle CDatDplnnic qledillplnQm

12&I

llllarior 1II rib llllarior 2nd rll

apw

caclCD CPI

C11111Caid process

di g

M:Ia

lbr lpalvmi p3 p4 PIIll

mf

gllllric llubble infwior 'II'WII Cll\'& left abium lift nw*1stam bronctus IIIII pulmarwy lrlely lift vantricla major fissurap.,.riar 3ld rll p.,.riar 4th rll main iiUmanary artery rightalli1.111 right maillltem bronchus rightidnanary artery right vanlliclaSCBpWI

minur&.u11

rtJrrpll

rvIC

liP

st

Vllw

Llllaral Villw

svc1r

ll!linDUJ prDCAI stamum

superior- CIMI verblbnll bodyhehell

vb

Figura Z. Locatio of

MadiMiiul Structures and Bony l.andarks Tbla 1 Localizlllion Uaing th Silllauatta Sign

ANATOMY

Localizing Lesions silhouette lip: loss of normal interfaces due to lung pathology (consolidation, atelectasis, mass), which can be used to localize disease in specific lung segments note that pleural or mediastinal disease can also prodw::e the silhouette signAPPROACH TO CXRBasics ID: patient name, MRN, sex. age

s.nar VIlli Cftll8/ IIUL right ..,eriar lllldiastin1111 Right h..t bl:l'der RML Right hrllliliaiM!Jn RUAoltic knr.b' WL 18ft si4)111iar mediaslillm

date ofexam marken: Rand/or L technique: view (e.g. PA, AP, lateml), supine or erect

indications fur the !tudy comparison: date ofprevious study for comparison (ifavallable) quality of film: Inspiration. penetration and rotation

l.aft h111rt border 1.a1t hamdii!IDIIIm

l.ir;lula UL

Analysis tuba and llnet; chec::k position and be alert fur pneumothorax or pneumomediastinum soft tiJaaes: neck, axillae, pectoral muscles, breasts/nipples, chest wall nipple markers can help identify nipples (may mimic lung nodules) amount ofsoft tissue, presence of maases and air (subcutaneous emphysema) abdomen (see GI imaging. DMll): free air under the diaphragm air fluid levels, dlstentl.on in small and large bowels herniation ofabdominal contents bona: C-spine, thoracic spine, shoulders, ribs, sternum lytic and blastic lesions and fractures mediastinuln; trachea, heart, great vessels, mediastinum, spine cardia.c enlargement, tra.chea.l shift, tortuous aorta. widened mediastinum Iilla: pulmonary vessels, mainstem and segmental bronchi, lymph nodes lunp lung parenchyma. pleura. diaphragm lungs on lateral film should become darker when going Inferiorly over the spine comment on abnormal lung opacity, pleural effusions or thickening right hemidlapluagm usually hlgher than left due to liver right vs.left hemidiaphragm can be discerned on lateral CXR due to heart resting directly on left hcmidiaphragm

C'-1 . . _ lwl*ilfllliula.iGa ABCDEF AP, PA ur ath viaw

BDC!v IIIIIB

Conm1l IBIII

lim; fur I:GIIII)IrilonAlllp.. ABCDEF Anvays.lnd hil Adenopathy

Banesand Breast shadows Clnliac lilhau8lt8 and

llillptngm end Digutiye lriCt Edges of llleurt

...

Fields {llrlg fieldll

DM6 Diagnostic Medical Imaging

Chest Imaging

Toronto Notes 2011

RUL RML RLL FrontAP Right-Lateral

LLL

LUL LLL

"'

BackAP

Left-Lateral

Il@

RUL: Right Upper Lobe; RML: Right Middle Lobe; RLL: Right Lower Lobe; LUL: Left Upper Lobe; LLL: Left Lower Lobe Figure 3. Location of Lobes of the Lung

Computed Tomography (CT) ChestAPPROACH TO CT CHEST lung window central-trachea: patency, secretions bronchial trees: anatomic variants, mucus plugs, airway collapse lung parenchyma: fissures, nodules bone window look at vertebrae, sternum, manubrium, ribs for fractures, lytic lesions, sclerosis soft tissue window thyroid, chest wall, pleura heart: chambers, coronary artery calcifications, pericardium vessels: aorta, pulmonary artery, smaller vasculature lymph nodes: mediastinal, axillary TYPES OF CT CHESTTable 4. Types of CT Chest Standard Advantage Scans full lung very quickly (< 1 minute} High Resolution Thinner slices provide high definition of lung parenchyma Only 5-1 0% lung is sampled No Hemoptysis Diffuse lung disease (e.g. sarcoidosis, hypersensitivity pneumonitis, pneumoconiosis} Pulmonary fibrosis Nonnal CXR but abnonnal PFTs Characterize solitary pulmonary nodule Low Dose 1/5th the radiation Decreased detail No

CT AngiographyIodinated contrast highlights vasculature Contrast can cause severe allergic reaction and is nephrotoxic Yes

Disadvantage Poor at evaluating diffuse disease Contrast Indication Figure 4. CT Thorax Windows CXR abnonnality Pleural and mediastinal abnormality Lung cancer staging Follow up metastases Empyema vs. abscess

Screening Pulmonary embolism Follow up infections, Aortic aneurysms lung transplant, Aortic dissection metastases

....._'

DDx of Airspace Disease Pus (e.g. pneumonia) Fluid (e.g. pulmonary edema) Blood (e.g. pulmonary hemorrhage) Cells (e.g. bronchioalveolar carcinoma; lymphoma) Protein (e.g. alveolar proteinosis)

.

, .-------------------,

Lung AbnormalitiesATELECTASIS pathophysiology: collapse of alveoli due to restricted breathing, blockage of bronchi, external compression or poor surfactant signs increased opacity of involved segment/lobe, silhouette sign volume loss: fissure deviation, hilar/mediastinal displacement, diaphragm elevation vascular crowding compensatory hyperinflation of remaining normal lung air bronchograms (also seen in consolidation) differential obstructive (most common}: air distal to obstruction is reabsorbed causing alveolar collapse endobronchial lesion, foreign body, inflammation (granulomatous infections, pneumoconiosis, sarcoidosis, radiation injury} or mucous plug (seen in cystic fibrosis) compressive tumour, bulla, effusion, enlarged heart, lymphadenopathy traction (cicatrization}: due to scarring, which distorts alveoli and contracts the lung adhesive: due to lack of surfactant hyaline membrane disease, prematurity passive (relaxation}: a result of air or fluid in the pleural space pleural effusion, pneumothorax management: in the absence of a known etiology, persisting atelectasis must be investigated (CT thorax) to rule out a bronchogenic carcinoma

....._'

}-------------------,

,

DDx of Interstitial Disease Pulmonary edema Collagen disease (e.g. fibrosis) Sarcoidosis Pneumoconiosis Metastatic disease (e.g. lymphangitic permeation) Inflammatory conditions (e.g. early viral pneumonia, interstitial pneumonia)

Toronto Notes 2011

Cheat lrnagins

Diapostic MedicallnlaginB DM7

CONSOLIDATION pathophysiology: fluid (water, blood), inflammatory exudates, or tumour in alveoli signs air bronchograms: lucent branching bronchi visible through opacification airspace nodules: fluffy, patchy, poorly marginated appearance with later tendency to coalesce, may take on lobar or segmental distribution

cWferential fluid: pulmonary edema, blood (trauma, vasculitis, bleeding disorder, pulmonary infarct) inflammatory exudates: bacterial infections, TB, allergic hypersensitivity alveolitis, bronchiolitis obliterans organizing pneumonia (BOOP), allergic bronchopulmonary aspergillosis (ABPA), aspiration, sarcoidosis tumour: bronchioalveolar carcinoma, lymphoma management: in the absence of a known etiology, persisting atelectasis must be investigated (Cf thorax) to rule out a bronchogenic carcinomaINTERSTITIAL DISEASE pathophysiology: pathological process involving the interlobular connective tissue (ie. "scaffolding of the lung") signs

linear: fine lines caused by thickened connective tissue septae Kerley A: long thin lines in upper lobes Kerley B: short horizontal lines extending from lateral lung margin Kerley C: diffuse linear pattern throughout lung nodular: 1-5 mm well-defined nodules distributed evenly throughout lung seen in malignancy, pneumoconiosis and with granulomas (sarcoidosis, miliary TB) reticular (honeycomb): parenchyma replaced by thin-walled cysts suggesting extensive destruction of pulmonary tissue and fibrosis seen in interstitial pulmonary fibrosis (IPF), asbestosis and CVD NOTE: watch for pneumothorax as a complication reticulonodular: combination of reticular and nodular patterns may also see signs of airspace disease (atelectasis and consolidation)

cWferential occupationallenvironmental exposure inorganic: asbestosis, coal miner's pneumoconiosis, silicosis, berylliosis, talc pneumoconiosis organic: bird fancier's lung, farmer's lung (moldy hay) autoimmune: CVD, IBD, celiac diseae, vasculitis drug-related: antibiotics (cephalosporins, nitrofurantoin), NSAIDs, phenytoin, carbamazepine, fluoxetine, chemotherapy, heroin, cocaine, methadone idiopathic: hypersensitivity pneumonitis, IPF, BOOP management high resolution CT thorax biopsy

PULMONARY NODULE (see Table 5) signs: round opacity silhoutte sign note: do not mistake nipple shadows for nodules; ifin doubt, repeat CXR with nipple markers

cWferential atrapulmonary density: nipple, skin lesion, electrode, pleural mass, bony lesion solitary nodule: tumour: carcinoma, hamartoma, metastasis, bronchial adenoma inflammation: histoplasmoma, tuberculoma, coccidioidomycosis vascular: AV fistula, pulmonary varix (dilated pulmonary vein), infarct, embolism multiple nodules: metastases, abscess, granulomatous lung disease (TB, fungal, sarcoid, rheumatoid nodules, silicosis, Wegener's disease) management clinical information and CT appearance determine level of suspicion of malignancy ifhigh probability, invasive testing (fine needle aspiration, transbronchialltransthoracic biopsy) is indicated iflow probability; repeat CXR or CT in 1-3 months and then every 6 months for 2 years; if no change, then >99% chance benign

DDx for Cavibding Ling NoduleWEIRD HOLES Wegener's syndrome Embolic (pulm0111ry, septic) Infection (111aerobes, pnewnocystis, TB) RhliUfiiBtoid [necrobiotic: nodules) Developmental cysts (sequeslration)Hisliocyloai5 Oncologiclll Lymphangioleiomyomalulil Environmental, occupetiOIIII San:oidosis

DM8 Diapltic Mecllcal. ImagiDg

Chest Imging

1'oroDio

2011

Tabl111 S. Cllaracblristics af 14111ign ..d Mlllignallt Pulmonary NadulasMlligl&lt ......

Mlfgil

11-llafinal!/spicaltlld ("corana 111diala"}

Wall-dalilad

I.QbuletedEccanlric or stippled

SmoathDilfusa. cantnt popcom. concanlric

2.0-4&0 days Cllllillltian. collapse, aclerqMdlrf, plaural aflusi.m, lytic bona lailllt smliing hisloly

460 days

c-blia&ltllita Lllilnl

Ya&, apacialy wi1h Wlllllhkina&s > 15 nm.

ND

acctllbic ciMty llld shaggy illemal nwgiiS

No

Yes

Pulmonary Vascular AbnormalitiesPULMONARY EDEMA

&ifpu vucular redistribution/enlargement, pleural c:ffusi.on, cardiomegaly (may be present in cardiogenic edema and fluid overloaded states) edema. fluid iDitially collects in interstitium: loss ofdefinition of pulmonary vasculature peribronchial cuffing Kerley 8 lines reticulonodular pattern thickening of interlobar fissures as pulmonary edema progresses, fluid begins to collect in alveoli causing dUfuse air space disease often ln a "bat wing" or "butterfly"' pattern in perlhilar regions with tendency to spare the outermost lung fields differartial: cardiogenic (CHF), renal failure. volume overload, non-cardiogenic (ARDS)Figure 5. P11unl Ellusian i Lateral ViewPULMONARY EMBOLISM lignl: Westermark sign (localized pulmonary oligemia), Hampton's hump (triangular peripheral

in!arct), enlarged RV and RA, pulmonary edema, atelectasis, pleural effusion JIUIDII8CIIle.DI: V /Q scan, CT angiography (look for :filling defect)

Pleural AbnormalitiesPLEURAL EFFUSION

T1bla &. S1nlitivity af ...in Flm Viavn for Plaunl Effulion 25 ml- most sniliv& 50 ml- mrilcus seen in the pDS!sill' cosloplumic sli:us2IXl mL

Dlfusa IIIZila&s

Figure 6. PnelllnOihonx

'.

.. ,

a horizontal fluid level is seen only in a hydropneumothorax (both fluid and air within pleural cavity) effu&ion may aert mass effect. shift trachea and mediastinum to opposite side, or cause

Bllnted 1111111111....... Slftlltl: lntra-tlldDmil'lll pniCBII Pragn11111:y Dillplwqma1ic plrlllysis Atllelrtuil lung IIIIBclion

atelectasis ofadjacent lung U/S is superior to plain film for detection of small effusions and may also aid in thoracentesisPNEUMOTHORAX

PnaumonactDmy Pleu1111 ellu&ion alao may rest.fl in eiiiVB!ioR. .,....._. .. Asl!ln.

COPD Large plau111l ellution T..nol6

&ifpu upright chest film allows visualization ofvisceral pleura as curvilinear line paralleling chest wall. separating partially collapsed lung from pleural air more obvious on expiratory (increased contrast between lung and air) or lateral decubitus film (air collects superiorly) more difficult to detect on supine film; look for the deep (costopbrenk:) sulcus" sign. double diaphragm sign (dome and anterior portions ofdiaphragm outlined by lung and pleural respectively), hyperlucent hemithorax, sharpening ofadjacent mediastinal structures mediastinal ahift may occur ifair is under tension ("tension pneumothorax") differeDtial: spontaneous (tall and thin males, smokers), iatrogenic (lung biopsy, ventilation, CVP line insertion), trauma (associated with rib fractures), emphysema, malignancy, honeycomb lung

Toronto Notes 2011

Cheat lrnagins

Diapostic MedicallnlaginB DM9

ASBESTOS

asbestos exposure may cause various pleural abnormalities including benign plaques (most common) that may calcify, diffuse pleural fibrosis, effusion, and malignant mesothelioma

Mediastinal AbnormalitiesMediastinal Mass the mediastinum is divided into three compartments; this provides the approach to the differential diagnosis of a mediastinal mass anterior (anterior line formed by anterior trachea and posterior border ofheart and great vessels) 4 T's: thyroid, thymic neoplasm (e.g. thymoma), teratoma. and "terrible" lymphoma cardiophrenic angle mass differential: thymic cyst, epicardial fat pad, foramen of Morgagni hernia middle (extending behind anterior mediastinum to a line 1 em posterior to the anterior border of the thoracic vertebral bodies) esophageal carcinoma. esophageal duplication cyst metastatic disease lymphadenopathy (all causes) hiatus hernia broncltogenic cyst posterior (posterior to the middle line described above) neurogenic tumour {e.g. neurofibroma. schwannoma) multiple myeloma pheochromocytoma neurenteric cyst, thoracic duct cyst lateral meningocele Bochdalek hernia extramedullary hematopoiesis in addition, any compartment may give rise to lymphoma. lung cancer, aortic aneurysm or other vascular abnormalities, abscess, and hematomaENLARGED CARDIAC SILHOUETTEDDx Alml MMiilllltinalllaa 411 ThyroidThymus

T11111Dm1"Terrible- lymphoma

....am.

,

DDx !If lncre.ed Canliclthar1cic

Cardiomegaly (myocnial dilatationor hypertrophyI

P&ricardial effusion Poor inapil'lllllry llffortAow lung volmes Pectus exCIVatum

heart borders on PA view, right heart border is formed by right atrium; left heart border is formed by left atrium and left ventricle on lateral view, anterior heart border is formed by right ventricle; posterior border is formed by left atrium (superior to left ventricle) and left ventricle cardiothoracic ratio = greatest transverse dimension of the central shadow relative to the greatest transverse dimension of the thoracic cavity in an adult, good quality erect PA chest film, cardiothoracic ratio of >0.5 is abnormal differential of ratio >0.5 cardiomegaly (myocardial dilatation or hypertrophy) pericardia! effusion poor inspiratory effort/low lung volumes pectus ex.cavatum ratio 7 em, splayed carina (late sign) right ventricular enlargement elevation of cardiac apex from diaphragm anterior enlargement leading to loss of retrosternal air space on lateral increased contact of RV against sternum left ventricular enlargement displacement of cardiac apex inferiorly and posteriorly "boot-shaped" heart Rigler's sign: on lateral film, from junction of IVC and heart at level of the left hemidiaphragm. measure 1.8 em posteriorly then 1.8 em superiorly -+ if cardiac shadow extends beyond this point, then LV enlargement is suggested note: not to be confused with Rigler's sign in the abdomen

DMIO Diagnostic Medkal Imql.ng

Chest Imging

1'oroDio

2011

Tubes, Lines, and Catheters ensure appropriate placement and assess potential complications oflines and tubes avoid mistaking a line/tube fur pathology (e.g. oxygen rebreathcr IIUUk fur pneumothoraces)Central Venous Catheter

prlma.rfiy used to administer tluids, medications, and vascular acceas fur hemodialyais - also monitor central venous pressure (CVP) tip must be located distal to (above) right atrium as this prevents catheter from producing arrhythmias or perforating wall of atrium ifmonitoring CVP - catheter tip must be proximal to venous valves tip of well positioned central venous catheter projects over silhouette ofSVC in a zone demarcated superiorly by the anterior first rib end and clavicle and .i.Dferiorly by top of RA course should paxallel course of SVC - ifappears to bend as it approaches wall of SVC or appears perpendicular, catheter may damage and ultimately perforate wall ofSVC compiJ.catioaJ: pneumothorax, bleeding (mediastinal, pleural), air embolism frontal chest film: tube projects over trachea and ahallow oblique or lateral chest radiograph will help determine position in 3 dimensions progressive gaseous disb:ntion of stomach on repeat imaging is concerning fur esophageal intubation tip should be located 4 em above tracheal carina- avoids selective intubation of right/left mainstem bronchus as patient moves, low enough so it does not rub against vocal chon:ls tube should not be inflated to the point that it continuously and completely occludes tracheal lumen as it may cause pressure induced necrosis of trachealJllUCOsa and predispose to rupture or stenosis .maximum inftation diameter 6 mm in outer diameter), enhancement of appendiceal wall, adjacent inflammatory stranding, appendicolith; a1so facilitates percutaneous abscess drainage Acute Diverticulitis most common site is rectosigmoid (diverticula are outpouchings of colon wall) CT is imaging modality of choice, although U/S is sometimes used oral and rectal contrast given before CT to opacify bowel cardinal signs: thickened wall, mesenteric infiltration, gas-filled diverticula, abscess CT can be used for percutaneous abscess drainage before or in lieu of surgical intervention sometimes difficult to distinguish from perforated cancer (therefore send abscess fluid for cytology and follow up with colonoscopy) if chronic, may see fistula (most common to bladder) or sinus tract (linear or branching structures) Acute Pancreatitis clinical/biochemical diagnosis imaging used to support diagnosis and evaluate for complications (diagnosis cannot be excluded by imaging alone) U/S good for screening and follow-up of a hypoechoic enlarged pancreas (although useless if ileus present as gas obscures pancreas) CT is useful in advanced stages of pancreatitis and in assessing for complications and is increasingly becoming the 1st line imaging test enlarged pancreas, edema, stranding changes in surrounding fat with indistinct fat planes, mesenteric and Gerota's fascia thickening, pseudocyst in lesser sac, abscess (gas or thickwalled fluid collection), pancreatic necrosis (low attenuation gas-containing non-enhancing pancreatic tissue), hemorrhage CT-guided needle aspiration and/or drainage done for abscess when clinically indicated pseudocyst may be followed by CT and drained if symptomatic

Angiography of Gl Tract GI tract arterial blood supply celiac artery: hepatic, splenic, gastroduodenal, left/right gastric superior mesenteric artery (SMA): jejunal, ileal, ileo-colic, right colic, middle colic inferior mesenteric artery (IMA): left colic, superior rectal imaging of GI tract vessels conventional angiogram: invasive (usual approach via femoral puncture), catheter used flush aortography: catheter injection into abdominal aorta, followed by selective arteriography of individual vessels CT angiogram: non-invasive using IV contrast (no catheterization required)

Genitourinary SystemModalitiesKUB (kidneys, ureters, bladder} a frontal supine radiograph ofthe abdomen useful in evaluation of radio-opaque renal stones (all stones but uric acid and indinavir), as well as indwelling ureteric stents or catheters addition of intravenous contrast excreted by the kidney (intravenous urogram) allows greater visualization of the urinary tract, but has been largely replaced by CT urography

....

,,

..,_ntltion Acuhl tntic!W pain = Doppler, UIS Amllnonhaa = UIS. MRI (brailf

Imaging Moll..ity Bun on

Flank pail = U/S, CT Hermduril = UIS, Cystoscopy, CT Infertility = Hystaroulpingooram. MRI Lowsr abdominal mass= UIS. CT Lower abdominal pain = U/S, CT R811111 colic = UIS. KUB, CT Tasticular m111 = UIS Unrthnll stricture

Bl011ting = UIS. CT

= Ure!hflJIIfllm

DMlt!i Diagnostic Medkal Imql.ng

1'oroDio

2011

Abdomi1111l CT plainCT good for general imaging of renal anatomy, although specific study types have supplanted plain CT for many indications, including CT urography (upper tract uroepithclial (renal masses) malignancies and renal calculi) and triphasic

cr 111'0JP'8phy

cr

ac.retory phase Imaging all.owa detafted assessment of urinary tract& high sensitivity (95%) for uroepi.thelial malignancies of the upper urinary tracts also useful fur usessment of renal calculi triphaeic CT standard imaging fur renal masses comprised of unenhanced, nephrographlc, and excretory phaaea allows accurate asseasment of renal arteries and veins and better characterization of suspldous renal masses, with particular utility in differentiating renal cell carcinoma from more benign masses

U/S initial study for evalUiltion of kidney size and nature of renal masse& (solid VII. cystic renal masses VII. complicatl:d cysts) technique of choice for screening patients with suspected hydronephrosis (no intravenous contrast InJection. no radiation to patient, and can be used in patients in renal failure) solid renal masses: echogenic (bright on U/S) cystic renal masses: smooth well-defined walls with anechoic interior (dark on U/S) complicated cysts: internal echoes within a thlclcened, irregular-walled cyst transrectal U/S (TRUS) useful to evaluate prostate gland and guide biopsies Doppler U/S to assess renal VB.llculatuze

Figure I. Triphlllic CT af an showing fat density with non-contrast scan. mildly anhandng with clllllrast

Retrograde Pyelography used to visualize the urinary collect:ing system via a cystoscope, ureteral catheterlzatlon, and retrograde InJection of contrast medium ordered when the intrarenal collecting system and ureters cannot be opacl1ied using Intravenous techniques (patient with impaired renal function, high grade obstructi.on) only yields information about the collecting systems (renal pelvis and usociated structures) no information regarding the parenchyma ofthe kidney Voiding Cystourethrogram (VCUG) bladder filled with contrast to the point where voldlng is trlggered real-time Images via fluoroscopy (continuous x-ray imaging) to visualize bladder contractility and evidence ofvesicoureteric reflux Indicat!ons: children with recurrent UTis, hydronephrosis, hydroureter, suspected lower urinary tract obstruction or vesicoureteral reflux

Retrograde Urethrogram used mainly to study strictures or trauma to the male urethra (Figure 10)

MRI strengths: high spatial and tissue resolution, lack of exposure to ionizing radiation and nephrotoxic contrast agents indicated over CT for depiction of renal masses in patients with previous nephron sparing surgery, patients requiring serial follow-ups (less radiation dosage), patients with reduced renal function. and patients with 90litary kidneysRenal Scan 2 radionucllde testa for kidney - renogram and morpbologl.cal scan renogram to assess renal function and collecting system useful in evaluation ofrenal failure, workup of urinary tract obstruction and hypertension, investigation of renal transplant intravenous injection of a radionuclide, technetium-99m. pentetate (Tc99m.-DTPA) or iodine-labeled hippurate, and imaged at 1-second intervals with a gamma camera over 30 minutes to assess perfusion delayed static images over the nat 30 minutes can be used to assess renal function andthe collecting system

Figure 9. Tltph811c CT af a R111a1 Cell CarciDml- showing arterial anhancamant and vanaua da-anhancamant

Uratllro.-m - demons'b'lting stricbJre in tha mambranaua urethra

Figure 1D. RlltrtJarada

morphologl.cal to assess renal anatomy study done with Tc99m-DMSA and Tc99m-glucoheptonate useful in investigation of renal mass and cortical scars

'IbroDlo Nota 2011

DiagnollkMedical Jma&lDg DM17

Gynecological Imaging transabdominal and transvaginal are the primary modalities, and are indicated for different scenarios transabdominal requires a full bladder to push out air containing loopa of bowel

U/S

good initiallnvestlgatlon for suspected pelvic pathology transvaginal approach provides enhanced detail of deeper/smaller structures by allowing use of higher frequency sound waves 81: reduced distances improved aase811ment of ovarie111, first trimester development. and ectopic pregnanciesHysterosalplngogram useful for assessing pathology of the uterine cavity and fallopian tubes, performed by x-ray images of the pelvis after cannulation of the cervix and subsequent injection ofopacifying agent particularly useful for evaluating uterine abnormalities (bicornuate uterus), or evaluation of fertility (absence offlow from tubes to peritoneal cavity indicates obstruction)

Flg1ra 11. TranuiMiomlul Ultrasaund- pregnancy, 18 vvk fetus

CT/MRI

excellent for evaluating pelvic structure111, especially those adjacent to the adnexa and uterus invaluable for staging gynecological malignancies

Selected Pathology

F"1111ra 12. Hptaroaalpingapamshowing left hydrosalpinxI

Renal Masses Bozniak classification for cystic renal masses classes I-II are benign and can be disregarded class IIF should be followed duseslll-IV are suspicioW!I for malignancy, requiring additional workupTable 1z. Boznlak Claultlcllloa for Cystic Renal Ma1881Sill,.. 1'111111 cylll Clnll Clnlll

-----------------------------------------

out by bllla-HCG before CT of afvmale pelvi (or any orgm performlid.

lhould always ba rulad i

Sane as class I + tile caaticatian ar lllllllerai:By11ickened c*ilicatian in septae II' Wills; also includes cys11 1 em} lhlt do not mnce with contrat CSF > air I= dark)

Co..lartRicym Clnllll

1lick

wals. caleific:atians. sep11118d. emn:ing Wills II' sapta with contrast

Atllludol

Rial call . . . . . a.. IV

Sirna as class II +salt tissue enhalv:anent with cantrast (dllinad as >10 Hounsfield Wlit R:rease. L"hanll:larizing wacuBityj with dHnharn:mant in VIllOUS phasa nas af niCIDSis

..... ,

angiomyollpoma (a benign renal neoplasm comp