Tomography Essay

Computed tomography (CT) offers the advantages of 3D imaging with volumetric and multi-planar reconstructions (21, 22). Given the relatively high radiation doses involved, CT should not be used in place of conventional radiography, and should be restricted to critically ill children who may need neurosurgical intervention (21). Iterative reconstruction and all appropriate dose reduction techniques should be used to reduce radiation exposure (22). Non-contrast-enhanced CT is the imaging modality of choice for suspected head trauma, and has the advantage of being readily accessible with relatively quick acquisition times (1, 23, 25). It is highly sensitive and specific for the detection of acute cranial injury, intracranial haemorrhage, and secondary changes such as cerebral oedema and infarction (1, 23, 25). Fractures and soft tissue swelling can also be diagnosed on CT using appropriate window settings (26). Further evaluation with MRI may be helpful in the setting of an abnormal CT examination (22). Chest CT is highly sensitive at identifying fractures at all stages of healing, but exposes the child to significantly higher radiation dose than a chest x-ray (23). Contrast-enhanced CT of the

The effective dose of a skeletal survey using digital radiography is estimated to be 0.2mSv in infants up to 12 months old (2). The effective dose of a skeletal survey in children less than 2 years old is 0.8mSv (15). With an effective dose for bone scintigraphy of 3mSv in all age groups (15) and a head CT of 1.9mSv in a child up to 2.5 years old (24). Such low doses suggest that radiation should not be an overriding factor when deciding whether a skeletal survey is needed in suspected NAI cases (2). The risk of missed injuries and potentially returning a child to an abusive environment is the primary consideration