40 DAVID SUTTON

DAVID SUTTON PICTURES

DR. Muhammad Bin Zulfiqar PGR-FCPS III SIMS/SHL

• Fig. 40.1 Fibrous cortical defect arising in posteromedial aspect of the distal medial femur. (A) The abnormality is confined to the cortex with very fine shell of overlying bone and a sharply defined endosteal margin. (B) A bone scan demonstrates a slight increase in activity (arrow) at the site of the lesion.

• Fig. 40.2 Fibrous cortical defect in the upper medial tibia is shown on CT (arrow). Note the purely cortical position of the defect and its sharply defined margin. The thin shell of overlying bone is not seen completely because of the partial volume effect.

• Fig. 40.3 Non-ossifying fibroma of the distal tibia presenting with a fracture. The well-defined outline and eccentric position of the tumour are demonstrated together with sharply defined sclerotic margins.

• Fig. 40.4 Sclerosis of a non-ossifying fibroma. Incidental finding following multiple ligamentous injuries to the knee. (A) Conventional radiograph. Only a faint band of sclerosis is shown around the margins of the fibroma (arrows). Coronal T,-weighted (B) and STIR (C) MR images showing mixed fibrous and normal marrow replacement (arrows) within the involuted lesion. Tears of the anterior cruciate and medial collateral ligaments are also evident.

• Fig. 40.5 Desmoplastic fibroma. A destructive, lobulated lesion is present in the distal metadiaphysis of the humerus. Bone expansion is present with sclerotic margins around the tumour. A soft-tissue component has caused consolidated periosteal new bone formation.

• Fig. 40.6 Fibrosarcoma presenting with pathological fracture of the femur in a woman of 50. Ill-defined bone destruction, particularly of the medulla, is associated with very minor periosteal new bone formation and no sclerosis. The cortex has been thinned on the endosteal surface.

Fig. 40.7 Fibrosarcoma arising in the medulla of the femoral head and neck. This 35-year-old man presented with poorly localised pain in the hip. (A) At presentation an ill-defined area of bone destruction on the medial aspect of the femoral head and neck. The cortex is preserved with no new bone formation. (B) Three months later a pathological fracture has occurred through the destructive lesion.

• Fig. 40.8 Malignant fibrous histiocytoma arising in the sacral ala of a 60-year-old woman. (A) A purely destructive, lytic lesion is present with slight sclerosis around its margins. Note that the lower border of L5 has also been destroyed together with part of the iliac wing. (B) A radionuclide bone scan shows the tumour to be photon deficient but a rim of increased activity corresponds to reactive bone sclerosis.

• Fig. 40.9 Adamantinoma of the tibia. Eccentric areas of bone destruction are present anteriorly with thinning of the cortex. The cortex is expanded. In addition to this abnormality, sclerosis and ill-defined cortical thickening are present throughout the whole of the tibia, which is also bowed. These features are due to associated fibrous dysplasia (or a close variety sometimes known as ossifying fibroma which occurs only at this site). (A) AP view. (B) Lateral view.

• Fig. 40.10 Giant cell tumour arising in the distal radius of an adult man. A characteristic, eccentric, immediately subarticular position makes this diagnosis very probable. The margins are ill defined with no sclerotic reaction.

• Fig. 40.11 Giant cell tumour of the patella. Giant cell tumours can arise in almost any bone but those around the knee are particularly affected. Note the immediately subarticular, eccentric position of the tumour which is purely osteolytic with no sclerotic reaction. The epiphyses have fused.

• Fig. 40.12 Giant cell tumour of the distal femur. AP (A) and lateral (B) radiographs showing a large immediately subarticular osteolytic lesion with apparent trabeculation and a wide zone of transition proximally. A localised area of cortical expansion is demonstrated posteriorly with a thin overlying shell of bone.

• Fig. 40.12 Giant cell tumour of the distal femur. (C, D) CT sections through the lesion demonstrating the localised dorsal expansion and intact overlying cortex. The apparent trabeculation demonstrated on the conventional radiographs is shown to be due to unresorbed ridges of cortical or trabecular bone at the margins of the lesion.

• Fig. 40.13 A giant cell tumour of humerus. Coronal T 1 -weighted (A) and axial STIR (B) sequences demonstrate a large lobulated mass in the humeral head and neck replacing all normal bone structures. Note the close approximation to the articular surface and the displaced axillary vessels.

• Fig. 40.14 Giant cell-rich osteosarcoma. (A) A radiograph of this boy at presentation demonstrates an eccentric, purely osteolytic lesion in the upper tibial metaphysis. The cortex has been breached but there is no periosteal new bone and only very faint surrounding sclerosis. (B) Six months later, following curettage and packing with bone chips, the flagrantly aggressive nature of this tumour is obvious. Note now the Codman's triangle on the lateral aspect of the tibial shaft and a substantial soft-tissue mass that contains ossification.

• Fig. 40.15 Brown tumour of hyperparathyroidism simulating the appearance of a giant cell tumour. An osteolytic lesion in the proximal ulna is shown extending to the immediate subarticular region. The margins are poorly defined and there is marked thinning and expansion of the dorsal cortex (arrowheads). A clue to the correct diagnosis, however, is provided by the subtle chondrocalcinosis of the articular surface radial head (curved arrow).

• Fig. 40.16 Large subarticular geode mimicking a giant cell tumour. (A) Conventional AP radiograph showing a large subarticular osteolucency with well defined distal margins in the proximal tibia. Prominent medial compartment osteoarthritis is shown. Sagittal T1 -weighted (B) and coronal STIR (C) MR images showing the multiloculated cystic nature of the tibial geode and the well-marked knee joint osteoarthritis.

• Fig. 40.17 Aneurysmal bone cyst arising from lamina and internal mass of C6 resulting in a unilateral dislocation of the facet joints in a 10 year old girl. Some extension into the adjacent vertebra of C7 is evident.

• Fig. 40.18 Aneurysmal bone cyst (boy aged two). This film was taken because of an asymptomatic swelling and shows the characteristic features of metaphyseal involvement, cortical expansion and thinning, with a relatively well defined endosteal margin.

• Fig. 40.19 Aneurysmal bone cyst of the proximal fibula. Considerably greater expansion has occurred in this example. The cortex is now very thin though apparently intact. The zone of transition between the lesion and adjacent bone is narrow but ill defined. Note apparent multiple septa within the lesion.

Fig 40.20 Aneurysmal bone cyst of the distal tibia. (A) Coronal T 1 -weighted image showing an expansile lesion of the distal metaphysis containing heterogeneous areas of low signal intensity. (B) Coronal T2 -weighted image. Apparently multiloculated high-signal intensity expansile lesion of the metaphysis. (C) Axial T2 -weighted image. Multiple fluid levels are demonstrated in the vascular spaces.

• Fig 40.21 Vertebral haemangiomas showing characteristic high signal intensity due to the associated fatty matrix on both the T1 - weighted (A) and T2 -weighted (B) images of the upper lumbar spine. The circular nature and speckled low-signal areas within the lesion are typical features.

• Fig. 40.22 Haemangioma of the vertebral body of L3. The whole body is marked by the characteristic vertical striation, which in this example does not extend into the pedicles.

• Fig. 40.24 Haemangioma of the middle finger middle phalanx with associated prominent soft-tissue component. (A) Conventional radiograph showing sclerotic striated phalanx of the middle finger and soft-tissue swelling. Coronal T 1 -weighted (B) and gradient-echo (C) MR images showing the extensive soft-tissue component of the cavernous haemangioma. The dilated abnormal vessels and vascular spaces appear as characteristic low-signal serpiginous channels on the T,-weighted sequence but have a high signal intensity on the gradient-echo image.

• Fig 40.23 Axial T2 -weighted image through the lumbar spine showing a vertebral haemangioma with a substantial extraosseous component. This results in considerable compromise to the thecal sac and widening of the right neural foramen.

• Fig. 40.25 Haemangioma of the inferior pubic ramus in a young woman. (A) Conventional radiograph showing an expansile osteolytic lesion within the inferior pubic ramus with cortical thinning and fine trabeculation extending into the posterior column of the acetabulum. An aneurysmal bone cyst, giant cell tumour or metastasis from a thyroid carcinoma or renal cell tumour should be considered in the differential diagnosis. Coronal T i -weighted (B), STIR (C) and axial T2 - weighted (D) MR images of the pelvis show the extent of the expansile lesion within the inferior pubic ramus and posterior acetabulum. Marked bony expansion is evident but there is no soft-tissue component to the tumor.

• Fig. 40.25 Haemangioma of the inferior pubic ramus in a young woman. (A) Conventional radiograph showing an expansile osteolytic lesion within the inferior pubic ramus with cortical thinning and fine trabeculation extending into the posterior column of the acetabulum. An aneurysmal bone cyst, giant cell tumour or metastasis from a thyroid carcinoma or renal cell tumour should be considered in the differential diagnosis. Coronal T i -weighted (B), STIR (C) and axial T2 - weighted (D) MR images of the pelvis show the extent of the expansile lesion within the inferior pubic ramus and posterior acetabulum. Marked bony expansion is evident but there is no soft-tissue component to the tumor.

• Fig. 40.26 Haemangioma of the skull is shown on a localised view of the temporal fossa. Note the purely osteolytic lesion with stippled radio densities.

• Fig. 40.27 Cavernous haemangioma of the soft tissues of the forearm is diagnosed by the presence of soft-tissue swelling within which there are phleboliths. The presence of extensive consolidated periosteal new bone and bowing of the ulna suggest an intimate relationship with the periosteum.

Fig. 40.28 Vertebral haemangioma was detected initially (A) on a whole body radionuclide bone scan in this middle-aged woman with carcinoma of the breast. A marked increase in activity is present throughout the whole of L3. (B) A radiograph demonstrates fine striation within an enlarged vertebral body. The pedicles, particularly that on the right, are enlarged. (C) CT confirms multiple radiolucencies throughout the vertebral body. This patient remained free of metastasis on annual follow-up for 5 years.

• Fig. 40.28 Vertebral haemangioma was detected initially (A) on a whole body radionuclide bone scan in this middle-aged woman with carcinoma of the breast. A marked increase in activity is present throughout the whole of L3. (B) A radiograph demonstrates fine striation within an enlarged vertebral body. The pedicles, particularly that on the right, are enlarged. (C) CT confirms multiple radiolucencies throughout the vertebral body. This patient remained free of metastasis on annual follow-up for 5 years.

• Fig. 40.29 Soft-tissue haemangioma of the great toe. This patient complained of a swollen great toe with a purple area of discoloration. (A) A plain film reveals soft-tissue swelling and pressure erosion of the plantar aspect of the distal phalanx. (B) A blood-pool scan confirms an intense focus of activity (arrow) corresponding to the cavernous haemangioma.

• Fig. 40.30 Vanishing bone disease. A 70-yearold woman presented with poorly localised pain in her right hip. (A) A radiograph at presentation reveals ill defined destruction at the anterior inferior iliac spine. (B) Nine months later there is total destruction of the whole of the hemipelvis and hip joint. Note the faint outline of the residual femoral head (curved arrow), pathological fracture of the femoral neck and the articular surfaces of the sacrum and symphysis pubis which no longer articulate with bone (open arrows

• Fig. 40.31 Cystic angiomatosis of bone. Shortly before taking his university entrance examination this young man complained of a vague discomfort in his right shoulder. Note multiple well-defined radiolucencies involving the acromion, coracoid, glenoid and upper humeral shaft. The latter has a rather 'woodworm'-like appearance. Lesions were present elsewhere in the skeleton but he had no soft tissue abnormality.

• Fig. 40.32 Glomus tumour. Intermittent swelling of the index finger had been present for many years and had, intermittently, been exquisitely painful. A discrete soft-tissue mass caused pressure erosion on the radial side of the terminal phalanx.

• Fig. 40.33 Neurofibroma arising in the exit foramen of the first sacral segment. The patient presented with sciatic pain and two views (A) from a water-soluble radiculogram reveal amputation of the S1 nerve root sheath, displacement of the S1 and S2 roots and a large well-defined rounded radiolucency with sclerotic margins in the exit foramen. (B) Frontal tomograms confirm a large bony defect (arrow), compared with the normal right foramen.

• Fig. 40.33 Neurofibroma arising in the exit foramen of the first sacral segment. The patient presented with sciatic pain and two views (A) from a water-soluble radiculogram reveal amputation of the S1 nerve root sheath, displacement of the S1 and S2 roots and a large well-defined rounded radiolucency with sclerotic margins in the exit foramen. (B) Frontal tomograms confirm a large bony defect (arrow), compared with the normal right foramen.

• Fig. 40.34 Neurofibroma demonstrated by coronal T 1 -weighted (A) and axial (B) MR images. A typical dumb-bell tumour is shown with large extraneural component. Note, however, there is extension into the exit foramen and other intrathecal abnormalities.

• Fig. 40.35 Neurofibroma arising in the obturator ring has caused considerable pressure erosion of both right pubic rami, particularly the superior one. The margins of the pressure defect are sharply defined.

• Fig. 40.36 Multiple neurofibromas in the cauda equina. This middle aged patient was investigated for low back pain by radiculography. Two large ovoid neurofibromas (arrows) are shown as filling defects within the thecal sac at the L4/5 level.

• Fig. 40.37 Neurofibromatosis. Pseudarthroses of the tibia and fibula shown in an infant. Bowing of bone and absence of any evidence of bone repair are typical.

• Fig. 40.38 Neurofibromatosis. ,4 lateral tomogram of the lumbar spine demonstrates typical posterior scalloping, part of the general dysplasia of the neural canal and its contents found in this condition.

• Fig. 40.39 Neurofibromatosis. A coronal T,-weighted sequence of the thighs demonstrates an obvious abnormality on the right. In addition to a solitary neurofibroma displacing the femoral vessels (shown by a signal void), there is clear mesenchymal dysplasia, with extensive abnormalities of subcutaneous tissue and hemihypertrophy.

• Fig. 40.40 Intraosseous lipoma within the calcaneum. Lateral (A) and axial (B) conventional radiograph showing an osteolytic lesion characteristically located between the major trabecular groups of the bone. A thin sclerotic margin surrounds the lesion that contains an eccentric stellate calcified focus. (C) Coronal CT of the hindfoot establishing the fat content of the lesion.

• Fig. 40.40 Intraosseous lipoma within the calcaneum. Lateral (A) and axial (B) conventional radiograph showing an osteolytic lesion characteristically located between the major trabecular groups of the bone. A thin sclerotic margin surrounds the lesion that contains an eccentric stellate calcified focus. (C) Coronal CT of the hindfoot establishing the fat content of the lesion.

• Fig. 40.41 Parosteal lipoma. Two examples are shown of parosteal lipomas arising in middle-aged patients. Both presented with a painless, rather firm mass, apparently attached to bone. (A) A large lesion arising on the lateral aspect of the femur. Note the strands of ossification surrounding the radiolucent areas of fat. (B, C) A more discrete tumour arises from the interosseous membrane of the forearm. A fatty radiolucency is present, together with ossification in the soft tissues and some periosteal bone formation.

• Fig. 40.41 Parosteal lipoma. Two examples are shown of parosteal lipomas arising in middle-aged patients. Both presented with a painless, rather firm mass, apparently attached to bone. (A) A large lesion arising on the lateral aspect of the femur. Note the strands of ossification surrounding the radiolucent areas of fat. (B, C) A more discrete tumour arises from the interosseous membrane of the forearm. A fatty radiolucency is present, together with ossification in the soft tissues and some periosteal bone formation.

• Fig. 40.42 Chordoma of the distal sacrum. (A) A lateral film demonstrates a large soft-tissue mass displacing bowel anteriorly. The anterior cortex of the distal sacral vertebrae is ill defined and the coccyx is not seen. (B) CT demonstrates the typical well-defined soft tissue mass extending anteriorly from the sacrum. The anterior cortex of the sacrum has been destroyed. Chordomas usually exhibit an apparent disproportion between the size of the soft-tissue mass and the extent of the bony involvement.

• Fig. 40.43 Implantation dermoid cyst. A cystic lesion in the terminal phalanx of the thumb was found in an elderly woman many years after a penetrating injury. The sharp definition of its margins and the location of the lesion are characteristic.

• Fig. 40.44 Synovial chondromatosis. Hundreds of calcified lesions are shown in relation to the synovium, all of them approximately the same size. Nearly all were loose bodies at arthroscopy.

• Fig. 40.45 Synovial chondromatosis of the knee. (A) Axial T2 - weighted fat-suppressed image showing numerous low-signal-intensity filling defects within the joint and thickened nodular synovium due to intrasynovial calcification. (B) In another patient a number of ossified masses of uniform size are present in a popliteal cyst. Medial compartment osteoarthritis is evident.

Fig. 40.46 Pigmented villonodular synovitis of the hip. (A) The conventional radiograph illustrates sharply defined radiolucent defects involving the acetabulum and the femoral head and neck. (B) The sharply defined nature of the lesions confirmed on tomography. Note the sclerotic. This patient has relatively advanced disease and joint space narrowing is present. (C) In another patient the well-defined radiolucencies are confined to the acetabular side of the joint and the joint space is preservedor widened.

Fig. 40.46 Pigmented villonodular synovitis of the hip. (A) The conventional radiograph illustrates sharply defined radiolucent defects involving the acetabulum and the femoral head and neck. (B) The sharply defined nature of the lesions confirmed on tomography. Note the sclerotic margins. This patient has relatively advanced disease and joint space narrowing is present. (C) In another patient the well-defined radiolucencies are confined to the acetabular side of the joint and the joint space is preserved or widened.

• Fig. 40.47 Pigmented villonodular synovitis of the hip. Coronal T1 -weighted (A) and STIR (B) sequences demonstrate a lobulated synovial mass on the right with modestly high signal on the STIR sequence, though less so than the joint effusion associated with it. Note the replacement of the pulvina on the T i - weighted sequence by tumour.

• Fig. 40.48 Pigmented villonodular synovitis of the index finger metacarpophalangeal joint. (A) An arthrogram confirms an enlarged joint space and thickened nodular synovium. In another patient the corresponding MR features are shown on coronal T 1 - weighted contrast-enchanted (B) and T2 -weighted fat-suppressed (C) images.

• Fig. 40.49 Pigmented villonodular synovitis of the knee joint. Axial T,-weighted (A) and T2 -weighted fat-suppressed (B) MR images through the patella and suprapatellar recess showing a heterogeneous mass within the joint made up of fat, haemosiderin, fibrous tissue and cellular elements.

• Fig. 40.50 (A,B) Pigmented villonodular synovitis of the flexor tendon sheath of the middle finger. A sharply circumscribed soft-tissue mass has caused slight pressure erosion of the middle phalanx.

• Fig. 40.51 Lipoma arborescens of the knee joint. Axial T1 -weighted (A) and T2 -weighted (B) fat-suppressed MR images through the suprapatellar recess showing numerous fatty fronds of synovium and a large joint effusion. Note how the high signal intensity villous projections on the T,-weighted image are suppressed on the T2 -weighted fat-suppressed sequence.

• Fig. 40.52 Dialysis-related amyloidosis of the hip resulting in pressure like erosions of the femoral neck. Note the coarsened quality of the trabecular bone due to secondary hyperparathyroidism.

• Fig. 40.53 Dialysis-related amyloidosis of the knee. Axial T1 -weighted (A), sagittal proton density (B) and T 2 -weighted (C) MR images showing numerous erosions of the margin of the tibia and characteristic low-signal-intensity masses within the synovium, most evident posteriorly within the popliteal cyst. A large joint effusion is also present.

• Fig. 40.54 Synovioma. A large soft-tissue mass is present posterior to the distal femur within which there is some amorphous eccentrically located calcification.

• Fig. 40.56 Intraosseous ganglion of the proximal fibula shown at a typical location. A slightly expansile lytic lesion is evident with endosteal thinning of the cortex and a well-defined margin.

• Fig. 40.57 Intraosseous ganglion. An oval, eccentric, osteolytic lesion arises from the medial malleolus with a thin sclerotic margin.

• Fig. 40.58 Subarticular geodes. (A) An elderly female with rheumatoid arthritis and secondary degenerative arthritis has a typical, large geode immediately beneath the articular surface of the tibia. (B) A younger male with rheumatoid disease has an oval, well-defined defect in the upper femoral neck. This too has a sclerotic margin. (C) Aspiration of the defect yielded synovial fluid and injection of contrast medium confirmed communication between the subarticular geode and the joint cavity.

• Fig. 40.59 Solitary bone cyst of the proximal femur showing expansion and thinning of the cortex, clearly defined endosteal margins but no calcification or periosteal new bone formation.

• Fig. 40.60 Solitary bone of the cyst proximal humerus. (A) This child presented with a pathological fracture through this long centrally located lytic lesion. Endosteal thinning and slight expansion is evident. There is no periosteal reaction and the distal extent of the lesion is well defined. Some 'fallen fragments' are present near to the fracture site. Coronal T1 -weighted (B), T2-weighted (C) and T 1 -weighted (D) contrast-enhanced fat-suppressed images. The extent of the lesion is well shown and is confined to the medullary canal of the humerus. Only the margins enhance consistent with a fluid-containing lesion. Some adjacent soft-tissueenhancement results from the fracture.

• Fig. 40.60 Solitary bone of the cyst proximal humerus. (A) This child presented with a pathological fracture through this long centrally located lytic lesion. Endosteal thinning and slight expansion is evident. There is no periosteal reaction and the distal extent of the lesion is well defined. Some 'fallen fragments' are present near to the fracture site. Coronal T1 -weighted (B), T2-weighted (C) and T 1 -weighted (D) contrast-enhanced fat-suppressed images. The extent of the lesion is well shown and is confined to the medullary canal of the humerus. Only the margins enhance consistent with a fluid-containing lesion. Some adjacent soft-tissue enhancement results from the fracture.

• Fig. 40.61 Solitary bone cyst arising in a typical site in the os calcis. The margins in this bone tend to be less well defined.

• Fig. 40.62 Solitary bone cyst of the distal femur. The lesion is rather atypical (A), and plain film diagnosis is not easy. However, it illustrates how further investigations can help in differential diagnosis. A bone scan in the blood pool phase (B) and in the delayed phase (C) shows increased activity around the margin of the lesion corresponding to sclerosis on plain film. (D) A CT scan demonstrates a soft-tissue density expansile lesion with no calcification. The differential diagnosis includes aneurysmal bone cyst, fibrous dysplasia ( monostotic) and a chondroma. Aneurysmal bone cyst is vascular in the blood-pool phase of a bone scan, fibrous dysplasia markedly so on the delayed scan. Calcification may be expected on CT in a chondroma.

• Fig. 40.62 Solitary bone cyst of the distal femur. The lesion is rather atypical (A), and plain film diagnosis is not easy. However, it illustrates how further investigations can help in differential diagnosis. A bone scan in the blood pool phase (B) and in the delayed phase (C) shows increased activity around the margin of the lesion corresponding to sclerosis on plain film. (D) A CT scan demonstrates a soft-tissue density expansile lesion with no calcification. The differential diagnosis includes aneurysmal bone cyst, fibrous dysplasia ( monostotic) and a chondroma. Aneurysmal bone cyst is vascular in the blood-pool phase of a bone scan, fibrous dysplasia markedly so on the delayed scan. Calcification may be expected on CT in a chondroma.

• Fig. 40.63 Ewing's sarcoma. The only abnormal sign here is of lamellar periosteal new bone arising from the superior pubic ramus on the right.

• Fig. 40.64 Ewing's sarcoma. This tumour is much more advanced, with a well-defined soft-tissue mass, Codman's triangles, ossification and calcification in the soft tissues and ill-defined bony destruction. The radiological distinction from osteosarcoma is difficult.

Fig. 40.65 Ewing's sarcoma arising primarily in the soft tissues of the thigh. A well-marked erosion ('saucerisation') defect has been caused with periosteal new bone formation. type of periosteal reaction is classically

• Fig. 40.66 Ewing's sarcoma of bone arising in the proximal fibula of an 8 year old. (A) An advanced tumour is shown on plain films, with Codman's triangles, a soft-tissue mass and ill-defined bone destruction. (B) The subtraction print of a femoral arteriogram demonstrates a very abnormal circulation with a large soft-tissue mass. (C) A bone scan, in the delayed phase, demonstrates increased activity where new bone formation is present on plain films. The lesion itself is photon deficient. Osteosarcoma may presentsi milar appearances.

• Fig. 40.66 Ewing's sarcoma of bone arising in the proximal fibula of an 8 year old. (A) An advanced tumour is shown on plain films, with Codman's triangles, a soft-tissue mass and ill-defined bone destruction. (B) The subtraction print of a femoral arteriogram demonstrates a very abnormal circulation with a large soft-tissue mass. (C) A bone scan, in the delayed phase, demonstrates increased activity where new bone formation is present on plain films. The lesion itself is photon deficient. Osteosarcoma may presentsi milar appearances.

• Fig. 40.67 Ewing's sarcoma of a lower rib. The conventional radiograph (A) shows a long moth-eaten lesion of the eleventh right rib which demonstrates prominent increased scintigraphic activity on the posterior bone scan (B). The extent of the associated soft-tissue mass, however, is best demonstrated on the CT (C) of the upper abdomen (dynamic enhanced scan).

• Fig. 40.68 Ewing's sarcoma of the anterior aspect of the right second rib. (A) On the conventional radiograph the appearances simulate an intrapulmonary lesion. (B) CT section showing destruction of the second rib and associated soft-tissue mass. (C) On the axial T 1 - weighted image the soft tissue component of the lesion has an intermediate signal intensity, and with the STIR sequence (D) an extremely high signal intensity.

• Fig. 40.68 Ewing's sarcoma of the anterior aspect of the right second rib. (A) On the conventional radiograph the appearances simulate an intrapulmonary lesion. (B) CT section showing destruction of the second rib and associated soft-tissue mass. (C) On the axial T 1 - weighted image the soft tissue component of the lesion has an intermediate signal intensity, and with the STIR sequence (D) an extremely high signal intensity.

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