CONTRIBUTION OF HIGH RESOLUTION ULTRASOUND IN THE ASSESSMENT OF BONE TUMORS A. MAALEJ, M. CHELLI BOUAZIZ, I. CHERIF, MF. LADEB Institut M.Kassab d’orthopédie. Ksar Said. Tunisia ARAB CONGRESS OF RADIOLOGY 2012MUSCULOSKELETAL : MK 20

INTRODUCTION  The diagnostic efficiency of high resolution ultrasound (US) is now admitted in a large variety of musculoskeletal diseases.  The purpose of our presentation is to demonstrate the diagnostic value of US in the assessment of bone tumors.

 Cortical bone constitutes a barrier to ultrasound transmission  However, juxtacortical and intra-osseous tumors with thinned or interrupted cortex remain accessible to ultrasound exploration  US allows :  distinction between liquid and solid tumor content;  Diagnosis of complicated osteochondromas;  Assessment of tumoral echotexture;  Post operative follow up INTRODUCTION

DISTINCTION BETWEEN SOLID AND LIQUID TUMOR CONTENT  Cystic tumors as well as ganglion bone cysts, can be diagnosed with a high level of confidence  Differential diagnoses: abcesses and haematomas

Subperiosteal ganglion cyst of the tibia. Radiograph, US and CT DISTINCTION BETWEEN SOLID AND LIQUID TUMOR CONTENT

ASSESSMENT OF TUMORAL ECHOTEXTURE  Internal septations or lobulations are easily seen as well as fluid-fluid levels.  Tumoral vascular pattern can be analyzed using Color Doppler

Chondrosarcoma of the phalanx: high resolution US shows a lobulated mass with cartilaginous calcifications and Color Doppler enhancement. ASSESSMENT OF TUMORAL ECHOTEXTURE

Essential bone cyst : high resolution US shows a homogeneous hypoechoic mass without lobulations or Doppler vascularity. CT and MRI show the same mass with a homogeneous cystic component.

Subperiosteal aneurysmal bone cyst of the radius. Fluid-fluid levels are easily seen on US ASSESSMENT OF TUMORAL ECHOTEXTURE

Aneurysmal bone cyst of the first metatarsal. US shows Fluid-fluid levels and Color Doppler enhancement of septa.

ASSESSMENT OF TUMORAL ECHOTEXTURE Osteoid osteoma of the ulna. US and CT appearance

CARTILAGINOUS TUMORS  Assessment of osteochondroma’s cartilaginous cap in appendicular skeleton.  Local complications: bursitis or pseudoaneurysms.

Femoral osteochondroma with thin cartilaginous cap: US and MRI. CARTILAGINOUS TUMORS

Tibial osteochondroma with thin and regular cartilaginous cap.

Malignant transformation of an osteochondroma: US shows thickening of the cartilaginous cap CARTILAGINOUS TUMORS

Local complications such as bursitis or pseudoaneurysms are easily diagnosed with US. Bursitis complicating a femoral osteochondroma: US and MRI appearance

CARTILAGINOUS TUMORS Bursitis complicating a tibial osteochondroma with peripheral color Doppler increased signal.

Psuedoaneurysm of the femoral artery in a patient with multiple osteochondromas. CARTILAGINOUS TUMORS

MALIGNANT BONE TUMORS The tumor, as well as cortical interruption and periosteal bone formation may be seen on US. US is also useful in the assessment of the articular and vascular extension of the tumor

Ewing’s tumor of the fibula. US shows a juxtacortical solid mass with irregular cortical interruption, new bone formation and important enhancement on color Doppler MALIGNANT BONE TUMORS

 Ultrasound can also be interesting in the follow up of malignant bone tumor after surgery because of CT and MRI artifacts. MALIGNANT BONE TUMORS Recurrence of an osteosarcoma of the distal femur. US shows a hypoechoic mass around the proximal end of the prothesis; Color Doppler shows a tumoral calcified thrombosis of the iliac vein (arrows)

MALIGNANT BONE TUMORS Recurrence of an osteosarcoma of the distal femur. US shows better than the CT the mass with important enhancement on color Doppler; Color Doppler shows also a tumoral thrombosis of the femoral vein.

CONCLUSION  High resolution ultrasound is useful in the the diagnosis and follow up of juxtacortical and intra-osseous tumors with thinned or interrupted cortex.  It allows a good assessment of tumoral echotexture  The use of Color Doppler shows tumoral vascular pattern