Thalassaemia

INTRODUCTION

• Thalassaemia, is an inherited blood disorder caused by defect in a gene causing microcytic anemia.

• The two types of thalassaemia is alpha and beta thalassaemia.

• Sign and symptoms of thalassaemia include weakness, fatigue, and failure to grow and organomegaly.

Radiographic features

• Skeletal• Marrow proliferation consists of expansion of the medulla,

thinning of cortical bone, and resorption of cancellous bone resulting in a generalized loss of bone density.

• skull : classic “hair on end” appearance• facial bones: rodent facies• ribs : “ribs within a rib” appearance, noted particularly in the

middle and anterior portions of the ribs• Extramedullary hematopoiesis• premature fusion of the epiphyses

The hair on end sign refers to a radiographic appearance on a skull which results from a periosteal reaction

Lateral skull from a patient with thalassemia major showing diploic widening with relative sparing of the occipital bone. Also note dental malocclusion and underpneumatized paranasal sinuses with rodent facies

“rib within a rib" appearance

marrow expansion and cortical thinning

Bilateral paravertebral soft-tissue masses as well as marked medullary expansion of the bony structures are associated with compensatory

extramedullary hematopoiesis.

Multiple myeloma

• In multiple myeloma, a group of plasma cells (myeloma cells) becomes cancerous and multiplies, raising the number of plasma cells to a higher than normal level.

• Clinical presentation of patients with multiple myeloma is varied, and includes :

• bone pain– initially intermittent, but becomes constant– worse with activity / weight bearing, and thus is worse during the day

• anaemia– typically normochromic / normocytic

• renal failure / proteinuria• Hypercalcaemia• pathological fracture

– vertebral compression fracture– long bone fracture (e.g. proximal femur)

• recurrent infection : e.g. pneumonia due to leucopoenia.

• Radiographic features• Radiology has a number of roles in the diagnosis and management or

multiple myeloma. • suggest the diagnosis / exclude other causes• assess possible mechanical complications (e.g. pathological fracture)• assess disease progression• Disseminated multiple myeloma has two common radiological

appearances:• numerous, well circumscribed lytic bone lesions : more common

– punched out lucencies e.g. pepperpot skull or raindrop skull– endosteal scalloping

• generalized osteopaenia : less common– often associated with vertebral compression fracture/ vertebral plana

The appearance of multiple, well-defined lytic lesions (punched out lesions) of various size scattered throughout the skull constitutes the raindrop skull / pepperpot

appearance of multiple myeloma.

• Endosteal scalloping refers to the focal resorption of the inner margin of cortical bones, typically seen in long bones,

due to slow growing medullary lesions.

LEUKEMIA

Leukemias are a group of heterogeneous neoplastic disorders of white blood cells.

INTRODUCTIONINTRODUCTION

Radiological Features

Radiographic osseous changes occur in 50-70% of children with leukemia

The radiological features Flat and long bonesCommon•Diffuse osteoporosis•Radiolucent submetaphyseal bands•Bone destruction•Periosteal reaction

Spine•Osteoporosis•Compression fractures•Radiolucent subendplate bands

Joints•Juxta-articular osteoporosis•Effusion•Soft tissue swelling

SKELETAL DISTRIBUTION OF LEUKEMIA

LEUKEMIA: RADIOLUCENT SUBMETAPHYSEAL BANDS. A.AP Knee.B.AP Hips.

Note that submetaphyseal bands (arrows) are often the first radiologic signs of childhood leukemia.

Radiolucent Submetaphyseal Bands.

A submetaphyseal band appears as a linear radiolucent region in the metaphysis beneath and parallel to the opaque zone of provisional calcification at the growth plate

LEUKEMIA: GROWTH ARREST LINES.

AP Knee. 

Note the multiple transverse linear opacities within the femur and tibia, which reflect the cyclic repression of bone growth in this child with leukemia.

LEUKEMIA: BONE DESTRUCTION. A.Early. Observe the discrete metaphyseal and diaphyseal lesions (arrows). 

B. Later. Note the more confluent, moth-eaten destruction, with periostitis, mimicking osteomyelitis.

LEUKEMIA. Lateral Thoracic Spine. Generalized osteoporosis and accentuated trabecular changes in this patient with chronic lymphatic leukemia.