Imaging in Diabetic Imaging in Diabetic footfoot

Department of Endocrinology Department of Endocrinology Postgraduate Institute of Medical Education and Postgraduate Institute of Medical Education and

Research Research ChandigarhChandigarh

Dr. Anil Bhansali

Mortality in DMMortality in DM Western WorldWestern World

Coronary artery disease Coronary artery disease 50-60%50-60% End stage renal disease End stage renal disease 30-40%30-40%

IndiaIndiaa) Sepsis a) Sepsis 46.5%46.5%- Pulmonary - Pulmonary 21%21%- Foot - Foot 8.3%8.3%- Others - Others 17%17%b) CAD b) CAD 17.4%17.4%c) ESRD c) ESRD 9.7%9.7%

Bhansali et al, Diab Res Clin Prac 2003

Why Imaging?Why Imaging? Sensorymotor neuropathySensorymotor neuropathy VasculopathyVasculopathy Lazy leukocyte syndromeLazy leukocyte syndrome Alters signs of inflammation Alters signs of inflammation Clinical examination may be Clinical examination may be

deceptive deceptive

Imaging modalitiesImaging modalities X-rayX-ray UltrasonographyUltrasonography Vascular DopplerVascular Doppler DSADSA CTCT MRIMRI Bone ScintigraphyBone Scintigraphy DEXADEXA

Major IssuesMajor Issues ForefootForefoot-- UlcerationUlceration-- OsteomyelitisOsteomyelitis Mid and HindfootMid and Hindfoot- Charcot’s joint Charcot’s joint

(with or without infection)(with or without infection)

X-ray FootX-ray Foot Soft tissue swellingSoft tissue swelling Foreign bodyForeign body Gas gangreneGas gangrene Vascular calcificationVascular calcification Loss of foot archLoss of foot arch Charcot’s arthropathyCharcot’s arthropathy AmputationsAmputations OsteomyelitisOsteomyelitis

Limitations of X-rayLimitations of X-ray OsteomyelitisOsteomyelitis-- Demineralization, periosteal Demineralization, periosteal

reactions and bony destruction reactions and bony destruction 30-50% of bone destruction30-50% of bone destruction Accuracy 50-60%Accuracy 50-60%

UltrasonographyUltrasonography Plantar abscessPlantar abscess Soft tissue collectionSoft tissue collection Associated DVTAssociated DVT

Doppler ImagingDoppler Imaging Vascular status Vascular status Site and extent of obstructionSite and extent of obstruction Collaterals Collaterals

DSADSA Better delineation than dopplerBetter delineation than doppler Higher sensitivityHigher sensitivity Before revascularisation procedure –Before revascularisation procedure –

mandatorymandatory Contrast induced nephropathyContrast induced nephropathy

Foot CT scanFoot CT scan Intraosseous gasIntraosseous gas SequestrumSequestrum Cortical bone defectsCortical bone defects Periosteal new bone formationPeriosteal new bone formation

Limitations of CT scanLimitations of CT scan SuppurationSuppuration Tissue edemaTissue edema Tissue fibrosisTissue fibrosis Granulomatous tissuesGranulomatous tissues

Foot: MR ImagingFoot: MR Imaging Anatomical detailsAnatomical details Osteomyelitis (Abnormal marrow Osteomyelitis (Abnormal marrow

signal, soft tissue mass and cortical signal, soft tissue mass and cortical destruction) destruction)

Neuropathic jointNeuropathic joint-- Disorganised destruction, dislocation, Disorganised destruction, dislocation,

marrow edema, effusion, loss of joint marrow edema, effusion, loss of joint definitiondefinition

Limitations of MRI Limitations of MRI ImagingImaging

Reactive marrow edema vs Reactive marrow edema vs osteomyelitis osteomyelitis

Hyperintensity on T2WI -marrow Hyperintensity on T2WI -marrow edemaedema

Expensive Expensive

Bone scintigraphyBone scintigraphy 99m99mTc MDP scanTc MDP scan Leucocyte scan (HMPAO-Leu)Leucocyte scan (HMPAO-Leu) Ciproflox scanCiproflox scan Marrow scan Marrow scan Radioabelled monoclonal antibodiesRadioabelled monoclonal antibodies

99m99mTc MDP ScanTc MDP Scan OsteomyelitisOsteomyelitis-- Sensitivity 100%Sensitivity 100%-- Specificity 30%Specificity 30% Non-infective inflammationNon-infective inflammation NeuroarthropathyNeuroarthropathy Traumatic fracturesTraumatic fractures

99m99mTc Ciproflox ScanTc Ciproflox Scan

OsteomyelitisOsteomyelitis Bone specific Bone specific

(sensitivity and specificity 90%)(sensitivity and specificity 90%) Ciplox sensitive organismCiplox sensitive organism Negative in sterile inflammationNegative in sterile inflammation

Bhansali and Dutta et al, Diab Res Clin Prac 2004

DEXADEXA Diabetic osteopathyDiabetic osteopathy Useful for monitoring bisphosphonate Useful for monitoring bisphosphonate

therapytherapy

ConclusionConclusion Foot sepsis is an important cause of Foot sepsis is an important cause of

morbidity and mortalitymorbidity and mortality Clinical examination is not a Clinical examination is not a

substitute for imaging substitute for imaging Leucocyte labelled scan and MRI are Leucocyte labelled scan and MRI are

useful modalities for diagnosing useful modalities for diagnosing osteomyelitisosteomyelitis