What Imaging Study What Imaging Study Should I Should I Order for …?Order for …?

Approach to Imaging for Approach to Imaging for Optimal Clinical Optimal Clinical

Diagnosis:Diagnosis: Musculoskeletal Musculoskeletal

DisordersDisordersDarius Biskup M.D.Darius Biskup M.D.

DisclosuresDisclosures

No financial disclosuresNo financial disclosures

Objectives:Objectives:

Review common musculoskeletal Review common musculoskeletal imaging modalities imaging modalities

Discuss advantages and Discuss advantages and disadvantages of imaging testsdisadvantages of imaging tests

Discuss use of contrast agentsDiscuss use of contrast agents Discuss imaging test approach to Discuss imaging test approach to

optimize clinical diagnosis of optimize clinical diagnosis of musculoskeletal disordersmusculoskeletal disorders

Common Musculoskeletal Common Musculoskeletal Imaging ModalitiesImaging Modalities

Plain filmPlain film FluoroscopyFluoroscopy CTCT MRIMRI Nuclear MedicineNuclear Medicine UltrasoundUltrasound

Advantages and Advantages and DisadvantagesDisadvantages

Knowing what a test can and can not Knowing what a test can and can not assess will help optimize test assess will help optimize test orderingordering

Plain filmPlain film

AdvantagesAdvantages Best initial test in Best initial test in

most clinical settingsmost clinical settings Quick/availableQuick/available Excellent boney Excellent boney

detaildetail Broad assessment Broad assessment Can offer clues to Can offer clues to

narrow next narrow next diagnostic stepdiagnostic step

Plain filmPlain film

DisadvantagesDisadvantages Poor assessment of Poor assessment of

soft tissuessoft tissues tendons, ligamentstendons, ligaments musclesmuscles organsorgans

Frequently negative Frequently negative for acute findings for acute findings more likely positive more likely positive

in acute traumain acute trauma

FluoroscopyFluoroscopy

AdvantagesAdvantages Offers dynamic Offers dynamic

assessment assessment Needle guidance Needle guidance

for arthrograms, for arthrograms, joint injections, joint injections, aspirationsaspirations

FluoroscopyFluoroscopy

DisadvantagesDisadvantages Limited Limited

assessment of soft assessment of soft tissuetissue Compliment with Compliment with

CT or MRI CT or MRI invasive – invasive –

arthrogram, arthrogram, injectioninjection

CTCT

AdvantagesAdvantages Noninvasive, Noninvasive,

quick, convenient quick, convenient Excellent detail of Excellent detail of

osseous anatomyosseous anatomy Surgical planningSurgical planning

CTCT

Disadvantages Disadvantages RadiationRadiation Allergic reactionAllergic reaction

IV contrastIV contrast Limitations in Limitations in

assessment of assessment of small soft tissue small soft tissue detaildetail tendons, ligaments, tendons, ligaments,

effusions, bursitiseffusions, bursitis

MRIMRI AdvantagesAdvantages No radiationNo radiation Excellent soft Excellent soft

tissue detailtissue detail Tendons, Tendons,

ligamentsligaments CartilageCartilage Soft tissue, Soft tissue,

MusclesMuscles MarrowMarrow

MRIMRI Disadvantages Disadvantages Pt claustrophobicPt claustrophobic

sedationsedation Limited assessment of Limited assessment of

osseous detailosseous detail Weight limitsWeight limits Metal susceptibility Metal susceptibility

artifactartifact Motion sensitiveMotion sensitive Takes time Takes time

Most scans 30 minutesMost scans 30 minutes

UltrasoundUltrasound AdvantagesAdvantages No radiationNo radiation Good targeted Good targeted

assessmentassessment Best initial test for Best initial test for

vascular assessmentvascular assessment DVT/ PVDDVT/ PVD Great test for Great test for

pediatric patientspediatric patients Biopsy/aspiration Biopsy/aspiration

guidance in soft guidance in soft tissuestissues

UltrasoundUltrasound

DisadvantageDisadvantages s

Operator Operator dependentdependent

Limited Limited assessmentassessment

Time Time dependantdependant

Nuclear MedicineNuclear Medicine

AdvantagesAdvantages Targeted examTargeted exam Functional/Functional/

metabolic exammetabolic exam Bone scan Bone scan WBC WBC

Indium/galliumIndium/gallium

Nuclear MedicineNuclear Medicine

Disadvantages Disadvantages Targeted exam Targeted exam Limited spatial Limited spatial

resolutionresolution May require May require

additional imaging additional imaging correlatecorrelate

abnormal activity on abnormal activity on bone scanbone scan

IV contrast for CT or IV contrast for CT or MRIMRI

Renal function Renal function important!important!

CT creatine < 1.5CT creatine < 1.5 MRI GFR > 45mL/min MRI GFR > 45mL/min

nephrogenic systemic nephrogenic systemic fibrosis (NSF) fibrosis (NSF)

No contrast for DialysisNo contrast for Dialysis

If renal function is If renal function is poor can always start poor can always start with non-contrast with non-contrast studystudy

Allergic reactionsAllergic reactions Mild – hivesMild – hives

pre-medicatepre-medicate Moderate Moderate

bronchospasm, bronchospasm, respiratory respiratory compromisecompromise consider another consider another

modality; do exam modality; do exam without contrastwithout contrast

SevereSevere- anaphylaxis – - anaphylaxis – NO contrast NO contrast

IV contrast not neededIV contrast not needed

MRI/CT imaging of MRI/CT imaging of jointsjoints Most MSK studies Most MSK studies

for joint assessment for joint assessment do NOT need do NOT need contrastcontrast

Fractures – occult, Fractures – occult, nonunion nonunion

Pre op planningPre op planning

When to order IV When to order IV contrastcontrast

Any study assessing Any study assessing tumor/masstumor/mass Allows better Allows better

characterizationcharacterization Assess for “itis”Assess for “itis”

Cellulitis/abscessCellulitis/abscess osteomyelitisosteomyelitis

Post op lumbar Post op lumbar spinespine

MRA MRA Lower extremity Lower extremity

runoff - contrastrunoff - contrast When in doubt, let When in doubt, let

the radiologist the radiologist figure it outfigure it out Order MRI of … , Order MRI of … ,

contrast as needed.contrast as needed. Consider Consider

authorization issuesauthorization issues Talk to radiologistTalk to radiologist

Choosing the right imaging Choosing the right imaging test to optimize clinical test to optimize clinical

diagnosis diagnosis Xray – most Xray – most

utilized modality utilized modality and most and most commonly order in commonly order in initial evaluationinitial evaluation

CT – multiplanar CT – multiplanar bony detail- bony detail- complex fractures, complex fractures, osseous lesionsosseous lesions

MRIMRI Tendons, ligaments, Tendons, ligaments,

marrow edema marrow edema contusionscontusions

Internal derangementInternal derangement

Nuclear medicineNuclear medicine Bone scanBone scan Indium/sulfur colloidIndium/sulfur colloid

US US Targeted assessmentTargeted assessment

Plain filmPlain film Excellent osseous detailExcellent osseous detail Key in initial evaluation of Key in initial evaluation of

joints joints Assess for Assess for

fractures/dislocationsfractures/dislocations ArthritisArthritis Osseous disorders/ Osseous disorders/

mineralizationmineralization Hardware evaluationHardware evaluation

CTCT Excellent osseous detailExcellent osseous detail Good soft tissue detailGood soft tissue detail Useful for postoperative Useful for postoperative

evaluation, complex evaluation, complex fractures, occult fx, fractures, occult fx, intra-articular loose intra-articular loose bodies,fluid collections, bodies,fluid collections, soft tissue gassoft tissue gas

Limited assessment of Limited assessment of menisci, labra, menisci, labra, ligaments, tendons, ligaments, tendons, marrow assessmentmarrow assessment

MRIMRI Superior soft tissue Superior soft tissue

detaildetail tendons, ligamentstendons, ligaments

Superior marrow Superior marrow evaluation evaluation Edema, contusions, Edema, contusions,

occult fx, osseous occult fx, osseous lesionslesions

Limited osseous detail Limited osseous detail evaluationevaluation

Ferromagnetic Ferromagnetic susceptibility artifact susceptibility artifact

Motion Motion Claustrophobic pt – can Claustrophobic pt – can

sedate patientssedate patients

Optimizing clinical Optimizing clinical diagnosis of diagnosis of MSK MSK disorders with imagingdisorders with imaging

Joint pain w/ negative Joint pain w/ negative findings/xray does not findings/xray does not

correlate correlate

hx decreased hx decreased ROM/ weakness/ ROM/ weakness/ impingement impingement

Plain film best Plain film best initial testinitial test

MRI to assess soft MRI to assess soft tissuetissue

TearTear vs vs TendinosisTendinosis

Full thickness tearFull thickness tear

Partial articular surface Partial articular surface teartear

Rotator cuff teasRotator cuff teas

Patient has Patient has pacemaker – pacemaker – can we still can we still evaluate evaluate rotator cuff?rotator cuff?

YES YES ArthrogramArthrogram CT arthrogram CT arthrogram

adds anatomyadds anatomy

Knee pain, Knee pain, negative xraynegative xray

Next step –MRI Next step –MRI MenisciMenisci LigamentsLigaments TendonsTendons

My patient has metal My patient has metal hardware, can I still order hardware, can I still order

an MRIan MRI

Is it useful?Is it useful?

Metal Artifact Reduction Metal Artifact Reduction Sequences (MARS) Sequences (MARS)

How do I order it?How do I order it?eg – MRI right hip eg – MRI right hip MARS protocol MARS protocol

Assess soft tissue, Assess soft tissue, effusions, fluid effusions, fluid collectionscollections

Tendons, Tendons, ligaments ligaments

Osteolysis adjacent Osteolysis adjacent to hardwareto hardware

Assessment of Assessment of internal internal derangement if not derangement if not joint replacementjoint replacement

Tumor/massTumor/mass

Mass/lump Mass/lump felt by felt by clinician or clinician or patientpatient

What to order What to order first?first?

Xray – best Xray – best initial stepinitial step

Extremity soft tissue Extremity soft tissue tumor/masstumor/mass

Abnormal xray/ normal xrayAbnormal xray/ normal xray If it can be normal, why order it?If it can be normal, why order it?

Can aid in assessment of mass – calcifications, bone Can aid in assessment of mass – calcifications, bone involvementinvolvement

What to order next?What to order next? MRIMRI How to order it? How to order it? MRI w/ & w/o contrast tumor/mass protocolMRI w/ & w/o contrast tumor/mass protocol

e.g. MRI right lower extremity tumor/mass e.g. MRI right lower extremity tumor/mass protocol w & w/o contrast protocol w & w/o contrast

Capsule marker Capsule marker placed around placed around massmass If mass not initially If mass not initially

found by patient, found by patient, show exact location show exact location so the can so the can reproduce site for reproduce site for examexam

Identifies target Identifies target mass vs. additional mass vs. additional not clinically not clinically detected lesionsdetected lesions

Fall, back pain, age Fall, back pain, age indeterminate compression indeterminate compression

fracture on xrayfracture on xray

What if patient has pacemaker and What if patient has pacemaker and there is a compression fracture there is a compression fracture deformity?deformity? Bone scan Bone scan

Imaging of spineImaging of spine

Back painBack pain Xray Xray

initial best testinitial best test

Imaging of spineImaging of spine

CT spine– no IV CT spine– no IV contastcontast Limited in assessment Limited in assessment

of spinal stenosisof spinal stenosis MRI spine w/oMRI spine w/o

most routine work for most routine work for LBP, radiculopathy LBP, radiculopathy

MRI spine w/ & w/oMRI spine w/ & w/o Post op follow upPost op follow up OncologyOncology

Can’t do MRI, but I Can’t do MRI, but I suspect central suspect central canal stenosiscanal stenosis CT myelogramCT myelogram

Low back pain, Low back pain, radiculopathyradiculopathy

CT myelogramCT myelogram

Good option Good option when can’t do when can’t do MRIMRI PacemakerPacemaker Post op metalPost op metal

InvasiveInvasive Contrast Contrast

injected into injected into thecal sacthecal sac

Nuclear Isotope StudiesNuclear Isotope Studies

Bone scan – infections, Bone scan – infections, osteomyeltits, stress/insufficiency osteomyeltits, stress/insufficiency fx “ diffuse bone pain”fx “ diffuse bone pain”

Limited spatial resolution – Limited spatial resolution – compliment with plain filmscompliment with plain films

Indium/sulfur colloid – infectionsIndium/sulfur colloid – infections esp with hardwareesp with hardware

Gallium- infectionsGallium- infections

I want to assess for I want to assess for osteomyeltis but my patient osteomyeltis but my patient

has a pacemakerhas a pacemaker No hardwareNo hardware Plain filmPlain film 3 phase bone scan3 phase bone scan Indium scanIndium scan (gallium in spine)(gallium in spine)

Hardware Hardware Plain filmPlain film 3 phase bone3 phase bone Induim/sulfur Induim/sulfur

colloid scancolloid scan Marrow Marrow

displacementdisplacement

I want to assess for I want to assess for hardware loosening vs hardware loosening vs

infectioninfection Plain filmPlain film 3 phase bone scan3 phase bone scan Induim/sulfur Induim/sulfur

colloid scancolloid scan Marrow Marrow

displacementdisplacement

Objectives:Objectives:

Review common musculoskeletal Review common musculoskeletal imaging modalities imaging modalities

Discuss advantages and Discuss advantages and disadvantages of imaging testsdisadvantages of imaging tests

Discuss use of contrast agentsDiscuss use of contrast agents Discuss imaging test approach to Discuss imaging test approach to

optimize clinical diagnosis of optimize clinical diagnosis of musculoskeletal disordersmusculoskeletal disorders

Take away pearlsTake away pearls Knowing what a Knowing what a

test can and can test can and can not assess will help not assess will help in optimal test in optimal test orderingordering

Xray most useful Xray most useful initial imaging initial imaging modalitymodality

MRI’s best done if MRI’s best done if targeted – soft tissue targeted – soft tissue mass, joint, limbmass, joint, limb Protocols differProtocols differ

Many exams can be Many exams can be substituted to get a substituted to get a diagnosis if a diagnosis if a condition prevents a condition prevents a desired examdesired exam Talk to your Talk to your

radiologistradiologist

Do I Need Contrast?Do I Need Contrast? Optimal forOptimal for Mass/oncology Mass/oncology ““Itis” –infection, Itis” –infection,

abscessabscess Post op Lumbar spinePost op Lumbar spine

Not neededNot needed MRI/CT of joints MRI/CT of joints

(not suspecting (not suspecting infection or mass)infection or mass)

When in doubt, let When in doubt, let the radiologist the radiologist figure it outfigure it out Talk to your Talk to your

radiologistradiologist

Questions?Questions?