Spine Marrow: Pathologic Fractures and Ditzels Mark E. Schweitzer, M.D. Chair and Professor of Radiology The University of Stony Brook Editor in Chief JMRI

MARROW SIGNAL Diffuse Multifocal Focal (as far as you can see)

CML cml

Multiple myeloma

T1 and T2 Low field QUESTION: What is the probability that this is malignant ? 0% 20% 40% 60% 80% pagets

Vertebral Marrow: Low Signal T1 only Higher specificity Diffuse or focal within vertebral body Fracture? Be careful T2 useful only if dark or halo

Multiple benign fractures

Is this a benign or malignant fracture?

breast met

BENIGN FRACTURES NO NOT IGNORE MORPHOLOGY Osteoporosis Trauma T score Cervical M > F Younger Thoracic Slightly older Usually below T7 Lumbar Older yet Osteoporosis A type of trauma Not cervical T7 and below Most at T10-L4 Most common L2 Most likely not to be benign L5 T score > -2.5 Only 1/3 of fragility NO NOT IGNORE MORPHOLOGY

Osteoporotic fractures

Path fracture mm

Compression? No Vertebral Body Yes No drop No Out-of-phase No Yes Follow up Bone scan Biopsy Yes No Is the marrow diffusely involved? No drop Is fx line present? No Out-of-phase No Yes Sequential? Drop >16% Benign Benign Benign Benign

Compression? Yes No Benign Benign Benign Benign Vertebral Body Is the marrow diffusely involved? Follow up Bone Scan Biopsy Yes No Fracture line? OUT OF PHASE No drop NO Sequential? Yes Drop > 16% Benign Benign Benign Benign

PATHOLOGIC FRACTURE: 2° SIGNS (I) Extensive involvement posterior elements including pedicle Non-sequential Large soft tissue mass or peridural Atypical locations: L5 Dens Upper to mid Thoracic Atypical appearance (one side worse, “irregular”) No fx line- or vertical

Compression 2° mets T1 Axial T1 STIR

Fx line= benign T1 T2

PATHOLOGIC FRACTURE: 2° SIGNS Extensive involvement posterior elements including pedicle Non-sequential Large soft tissue mass or peridural Atypical locations: L5 Dens Upper to mid Thoracic No fx line or vertical

PATHOLOGIC FRACTURE: 2° SIGNS No high signal in disc above Inferior > superior endplate ddx: metabolic bone disease No PLL avulsion Posterior bowing

PATHOLOGIC FRACTURE: 2° SIGNS No high signal in disc above Inferior > superior endplate Ddx: metabolic bone disease No PLL avulsion Posterior bowing Look for metastases elsewhere Look for benign fractures elsewhere

Korn

Benign fracture

Path fracture

T1 T2 fat sat Sequential

T1 T2 fat sat Metastases Posterior bowing Multiple bodies Posterior

Lung CA mets

Soft tissue mass especially peridural

Multiple Myeloma ALL FRACTURE LINES ARE NOT BENIGN Non horizontal malignant fx T1 T2 Gad ALL FRACTURE LINES ARE NOT BENIGN Non horizontal

Maligant inferior > superior

PATHOLOGIC FRACTURE: 2° SIGNS Look for metastases elsewhere Look for benign fractures elsewhere Remember curse of epidemiology

Pathologic fracture

lymphoma

T1 T1 in out Mets and malignant fx

T1 T2 Gad PLL avulsion Sequential location Complete fat/ degenerated disc T1 T2 Gad

Fracture and Met *No enhancement T1 T2 Gado

VERTEBRAL FACTURES DO NOT IGNORE LOCATION Risk of Malignancy Jefferson Teardrop (cervical) Chance Odontoid Burst Plana Anterior compression Atypical compression (r > l side, upper to mid T)

Breast path fracture

REMEMBER: ***Be cautious and follow-up*** Hyperacute traumatic/osteoporotic Fractures can look malignant ***Be cautious and follow-up***

Burst fracture mimking met

Acute osteoporotic mimic mets

If I am not sure, what should I do? Out of phase Follow-up/old films Tumor does not rapidly evolve Bone scan Thin slice CT X-ray Contrast Diffusion/perfusion/spectro

T1 T2 in out Xrt with out of phase

(also treatment response): CT signs of benignity (also treatment response): Sclerotic margins Central fat Typical Ca++ Treated mm with sclerotic rims

Treated MM

Benign fracture uses of gad

T1 GAD T2 CT

Kummel’s

3 weeks later Fx f/u

Two months later initial See scan 2 months before-acute fracture in feb Two months later initial

When should I not worry about a vertebra plana?

Leukemia T2 T1

VERTEBRA PLANA >75% loss of height Usually equal posterior and anterior ddx: Eosinophilic granuloma Metastases Osteoporotic fractures No more common to be malignant than more typical fractures Look at the rest of the spine

plana

T1 T2 Gad Lymphoma

plana

T1 T2

Malignant plana

What do I do with a low signal ditzel on a T1W image? If a portion of the vertebral body, different rules and lower threshold

Ditzel Focal T1 low signal Is it low on T2 is there a halo Yes probable met Bone island/ Endplate ^ >2cm out of phase Is there central fat Yes, red marrow 1-2 cm CT No and smaller then 1 cm or multifocal = Bone scan

Ditzel Focal T1 low signal Is it low on T2? Yes: probable met No; Is there a halo? Yes: probable met Yes =Bone island/ Endplate Δ >2cm out of phase does not ddx lesions Is there central fat? Yes: red marrow 1-2 cm CT No and smaller than 1 cm or multifocal = Bone scan

ALL, treated with 2nd necrosis

LOW SIGNAL DITZEL Single ditzel: Multiple ditzels: <1cm: CT >1cm: in and out of phase +/- thin slice MR >2cm: x-ray vs bone scan Multiple ditzels: <1cm: halo/ bullseye consider bone scan >1cm: bone scan vs. biopsy IF indeterminate, still low probability and f/u Moderate to High probability, need biopsy

Bone island-does not drop In phase is not a substitute for T1

T1W T2W (halo) Diffusion out of phase Breast met

L5 ditzel Subtle halo

T2- central high signal indeterminate T1-halo= benign

Lung mets

Rim bright on T1W Center bright on T2W

Lung mets

T2W gad Is there a role for contrast In short no Only to see epidural component T2W gad

Is that a bone island or a sclerotic met? Many sclerotic mets are not that low on T2W √ for reactive interface and homogeneity Size also, but helps to a lesser degree

T1 Bone island T2 T1

mets Malig schorl’s T1 Gad T2

T1 T2 Sclerotic mets

Sclerotic breast mets

Compression? Yes No Benign Benign Benign Benign Vertebral Body Is the marrow diffusely involved? Follow up Bone Scan Biopsy Yes No Fracture line? OUT OF PHASE No drop NO Sequential? Yes Drop > 16% Benign Benign Benign Benign

Ditzel Focal T1 low signal Is it low on T2? Yes: probable met No; Is there a halo? Yes =Bone island/ Endplate Δ Is there central fat? >2cm out of phase Yes: red marrow 1-2 cm CT No and smaller than 1 cm or multifocal = Bone scan

Compression? Yes No Benign Benign Benign Benign Vertebral Body Is the marrow diffusely involved? Follow up Bone Scan Biopsy Yes No Fracture line? OUT OF PHASE No drop NO Sequential? Yes Drop > 16% Benign Benign Benign Benign

T1 T2 Question: What is the probability that this is malignant? 20% 50% 75% 90% Lymphoma contiguous

Breat met

HALO AND BULLSEYE SIGNS periphery/center of a focal lesion HALOs T1: Benign T2: Malignant Bullseye sign = focal central fat Also benign Bullseye sign = central fluid Usually benign

in out Halo on out only

Mets variable sizes

SUBSETS OF METS Large soft tissue mass Calcification Isolated Thyroid, renal, hepatoma Calcification GI, usually colon Isolated Renal, breast Skeletal carcinomatosis Breast, prostate Distal Breast, renal If femur, lung Soft tissue Breast, lymphoma Cortical Lung Across joints/disc MM, prostate, lymphoma

MM across (around) disc space T1 Gad MM across (around) disc space

DISC SPACE INFECTIONS Usually bad luck Only a fraction immune function Only slight increase in DM Usually goes to only slightly degenerated disc vs. septic arthritis 2 º to transient bacteremia from skin or dental Often partially treated May result in peculiar appearances

Post op infection

DISC SPACE INFECTION Majority hematogenous spread Xray: MR: Also post-op Xray: Loss of disc height and erosions Look for paraspinal mass in T spine MR: Loss of disc space height, but increased T2W signal Endplate erosions or edema Epidural abcess, may look like phlegmon Dark on T2 or have vacuum phenomenon- o/w DDD Nuclear: gallium preferred

infection

Infection indium and sulfa colloid

ADVANCED IMAGING Infections begin in endplate Just beneath subchondral bone Concomitant osteomyelitis frequent Use overtness on T1 Epidural abscesses can look different than abscesses elsewhere Have more of a phlegmon appearance

Disc infection s/p tx

Infection

ORGANISMS Usually mono-except 1/3 of TB Blood cultures positive in 50% Staph > 76% Strep 2nd most common TB: 5%

disciits

Np spine no ghost sign

Atypical myco

Disc space infection

DISC SPACE INFECTION DDX Should not be anterior, skip, or show extensive spread to psoas- o/w TB Should not spread to facets, or show new bone formation- o/w chronic or NP spine Should not be dark on T2 or have vacuum phenomenon- o/w DDD or instability Other ddx:amyloid, subacute fractures, ank spond

tb

Disc space infection

Facet effusion with cyst

Midic/isstabil Instability

DISC SPACE INFECTION DDX Should not be anterior, skip, or show extensive spread to psoas- o/w TB Should not spread to facets, or show new bone formation- o/w chronic or NP spine Should not be dark on T2 or have vacuum phenomenon- o/w DDD Other ddx: amyloid, subacute fractures, ank spond

Ank spond

amyloid

Is this infection or… Segmental instability Bad Modic I change Neuropathic spine

Instability occult on MR

Bright T2 endplates T2 Listhesis = Instability Disc dark Disc Bright Abnl facets= NP  GE for vacuum Modic I O/W infection Yes = DDD

SPREAD OF DISC INFECTIONS Adjacent disc spaces Most often TB Facets Atypical in infections Psoas Through greater sciatic notch Lumbar plexus Iliopsoas bursa Hip

Facet infection

TB and ATYPICAL Immigrants/HIV: Massive worldwide frequency Lung disease present but seeding site usually GI/GU Looks like chronic/smoldering osteo difficult ddx May be osteo, articular or spondylitic In spine: Anterior Psoas abscesses May skip levels May result in Gibbus deformity Common superimposed pyogenic Often mimics typical discitis Parasites and ST TB- ca++

Pott’s

tb

tb

Diffuse marrow Lower than disc on T1 Drops on Salt and pepper out of phase = red marrow Salt and pepper = myeloma Look for nodes = lymphoma Check acetabulum and for bullseyes If yes benign if no o/w carcinomatosis, leukemia

MM Salt n’ peppa T2 T1

Two years later Early MM in out in out

CML CML T1 T2

Is this just weird normal marrow or multiple myeloma? MULTIPLE MYELOMA MR PATTERNS Multiple nearly similar sized Small areas  T2W Apparently red marrow (infiltration) Salt and pepper May have too many or atypical location of fxs Focal lesion (plasmacytoma)

T1 T2 Multiple myeloma almost nl Except for plasmacytoma

T1 T2 out MM normal except out-of-phase

Patchy Marrow on T1/T2-ignore T2 neither – in/out phase Check location Peripherally based = Benign Drop <16% = Benign Less or not drop – Bone Scan or BX Patchy Acetab also = Benign

Why is there fluid in that facet joint?

No, still likely OA vs. Instability Facet Fluid Focal Bilat Multifocal OA NP < lower = OA Focal Nl Geodes?/Spurs? Yes = OA No, still likely OA vs. Instability

Septic facet joint

Why is the marrow diffusely dark on T1W images? Skeletal carcinomatosis Too much normal red marrow Lymphoma Gauchers and other infiltrative Myelofibrosis Transfusions Multiple myeloma

Skeletal carcinomatosis

Red marrow

Carcinomatatous lowt2

WHY IS THE MARROW SO BRIGHT ON A T1 WEIGHTED IMAGE? Normal Too little normal red marrow Prior radiation therapy or other injury Aplastic anemia

Normal distribution of red/fatty marrow Normal fatty mimiking rt

Aplastic anemia

Increased fatty with red above s/p rt RT and Mets outside field

Why is the marrow so dark on T2W images? Normal Too much normal red marrow Anemia Transfusions Diffuse mets Lymphoma

Red marrow

CML cml

Transfusions

Why is there edema about the pedicle? OA Pars Met Extension of endplate reactive change

Pedicale edema from facet OA

Facet edema from OA

Thyroid ca with large soft tissue mass

Is this a met or an aggressive hemangioma? atypical hemangiomas often ST mass often subtle T1 multifocality

Could that be a vacuum in the vertebral body? And what does that mean?

charcot

AVN  KUMMEL’S Fx Collapse Delayed  collapse 2o to AVN Vacuum accentuated on extension

Kummel’s

Is that Paget’s or a Met?

PAGET’S Cortical thickening Double horizontal line sign Expansion Peculiar T1/T2 patterns

met

Could that Schmorl’s node be symptomatic?

TYPES OF SCHMORL’S Juvenile: low T1/T2 Vascularized-adj edema Acute/Traumatic- also edema Usually subacute Neoplastic-usu. Inferior endplates/ “chronic/slow growing” tumors prostate/breast

Malignant Schmorl’s

Neuropathic spine