Harvey E. L. Teo

Skeletal tuberculosis in children

The objective of this review is to present the imaging findings of skeletal tuberculosis in children. The incidence of tuberculosis is increasing and skeletal tuberculosis accounts for 10–20% of all extra-pulmonary cases. The most common manifestations of skeletal tuberculosis in children are spondylitis, arthritis and osteomyelitis. Tuberculous spondylitis involves the intervertebral disc only late in the disease. Subligamentous spread of the infection may lead to multiple levels of vertebral body involvement that may either be continuous or skipped. Extension of the disease into the paravertebral or extra-dural space may occur. Tuberculous arthritis usually occurs as a result of metaphyseal spread to the joint. Tuberculous osteomyelitis may appear as cystic, well-defined lesions, infiltrative lesions or spina ventosa. The latter is a term used to describe a form of tuberculous osteomyelitis where underlying bone destruction, overlying periosteal reaction and fusiform expansion of the bone results in cyst-like cavities with diaphyseal expansion. Radiographs are still the mainstay of evaluation of patients with bony lesions. Ultrasonography can detect soft-tissue extension of the bony lesions and guide drainage or biopsy procedures. CT accurately demonstrates bony sclerosis and destruction, especially in areas difficult to assess on radiographs such as the posterior elements of the vertebral body. MRI is the modality of choice in evaluating early marrow involvement and soft-tissue extension of the lesion.

Infantile lipofibromatosis of the upper limb

The imaging features of extensive lipofibromatosis presenting in a 1-day-old female infant are reported. This lesion involved her entire right upper limb, extending from the axilla to the palm of the hand. Radiographs showed marked deformity and thinning of all the right upper-limb bones due to pressure effect of soft-tissue enlargement, especially affecting the distal humerus and proximal forearm bones. Magnetic resonance imaging showed a huge soft-tissue mass infiltrating most of the muscles of the entire upper limb, with bony erosion. The mass was largely T1-isointense, moderately T2-hyperintense and showed marked enhancement. There were intra-lesional signal changes consistent with fatty elements. A lesion debulking procedure was performed and the histology was that of lipofibromatosis. The limb was found to be non-viable after the procedure and a subsequent above-elbow amputation was performed. Although the resection margins were not clear, she had no further recurrence over a subsequent 3-year follow-up period.

Intralobar Sequestration of the Lung Is a Congenital Anomaly: Anatomopathological Analysis of Four Cases Diagnosed in Fetal Life

The origin of intralobar sequestration of the lung (ILS)—whether congenital or acquired—has often been controversial, since firm anatomical evidence of prenatal origin has been sparse. We describe four cases in which anomalous arterial supply from the aorta to abnormally echogenic lower lung lobes was demonstrated on routine antenatal ultrasound examination, and the diagnosis of ILS was subsequently confirmed by postmortem examination including bronchography of the fetuses at between 20 and 23 wk. One right-sided lesion was supplied from a branch of the coeliac axis, and three left-sided lesions were supplied from the thoracic aorta. In two cases, the arterial supply was shown to be multiple. All lesions were situated in the lower lobes. They showed a cystic transformation of the affected lung tissue which was histologically indistinguishable from cases diagnosed as congenital cystic adenomatoid lesion (CCAM) at the same gestational age, but clearly different from that seen in bronchial obstruction due to laryngeal stenosis at that age. Similar vascular lesions have been reported in otherwise normal lungs. The character of the anomalous arterial vessels is consistent with origin from the embryonic splanchnic plexus. The precise sequence of pathogenetic events is unclear but there appears to be a close relationship of this condition not only with CCAM but also with the condition of anomalous arterial supply to the lower lobe.

Tropical pyomyositis and necrotizing fasciitis.

Pyomyositis is a purulent infection of skeletal muscle that arises from hematogenous spread, usually with abscess formation. Necrotizing fasciitis is a more severe, rapidly progressive infection involving the superficial and deep fascia with necrosis and fluid collections that can be life threatening if left untreated. Both conditions may coexist, and concomitant cellulitis is often seen. A high incidence of these diseases occurs in the tropics, but they are increasingly being seen in temperate countries, due in part to their association with immunodeficiency conditions such as human immunodeficiency virus (HIV) infection, diabetes mellitus, and organ transplantation. This article aims to familiarize physicians with these entities, review their clinical manifestations and imaging features, and highlight the role of imaging in the management of patients with these conditions.

Congenital osteofibrous dysplasia associated with pseudoarthrosis of the tibia and fibula

The association between congenital pseudoarthrosis and osteofibrous dysplasia of the tibia and fibula is a rare entity that has been recently recognized. We report a male newborn who was found to have swelling and deformity of the left lower leg. Radiographs and magnetic resonance imaging showed an extensive destructive lesion of the tibial shaft, with dysplastic congenital pseudoarthrosis of the lower fibula. Histopathologial examination confirmed the diagnosis of congenital pseudoarthrosis of the tibia and fibula with underlying osteofibrous dysplasia involving both bones. Immunohistochemical stains showed cytokeratin positivity.

The role of imaging in the staging and treatment planning of primary malignant bone tumors in children

The accurate staging of primary bone tumors in children is critical for treatment planning. Limb salvage operations can now be performed with excellent outcomes in suitable patients. The purpose of this article is to review the current state of imaging techniques and their roles in enabling accurate staging and treatment planning to be performed in pediatric patients with primary bone tumors.

Primary bone tumors of adulthood

Imaging plays a crucial role in the evaluation of primary bone tumors in adults. Initial radiographic evaluation is indicated in all cases with suspected primary bone tumors. Radiographs are useful for providing the diagnosis, a short list of differential diagnosis or at least indicating the degree of aggressiveness of the lesion. More detailed information about the lesion, such as cortical destruction or local spread, can be obtained using cross-sectional imaging techniques such as computed tomography and magnetic resonance imaging. This article discusses the characteristic features of the more common primary bone tumors of adulthood, and also the pre-treatment evaluation and staging of these lesions using imaging techniques.