From the Guidelines
A head CT with contrast is not recommended as the first-line imaging test for acute mental status change, delirium, and new onset psychosis, but it can be considered if intracranial infection, tumor, or inflammatory pathologies are suspected. The use of contrast-enhanced head CTs as a first-line test in the acute setting may not add significant value over noncontrast head CT examinations 1. However, in certain cases, such as suspected intracranial infection, tumor, or inflammatory pathologies, a contrast-enhanced CT examination can be valuable.
Some key points to consider when deciding on a head CT with contrast include:
- The patient's medical history, including any allergies to iodine or contrast materials, kidney problems, or pregnancy 1
- The potential risks and benefits of the procedure, including the risk of contrast-induced nephropathy and the importance of adequate hydration before and after the procedure 1
- The availability of alternative imaging modalities, such as MRI, which may be more sensitive for certain conditions 1
In general, a noncontrast head CT is the first-line neuroimaging test of choice for acute mental status change, delirium, and new onset psychosis, and can be performed safely and rapidly in all patients 1. However, if a contrast-enhanced CT is deemed necessary, it is essential to weigh the potential benefits against the potential risks and to take steps to minimize the risks, such as using low or iso-osmolar contrast agents and ensuring adequate hydration 1.
The procedure for a head CT with contrast typically takes about 15-30 minutes, during which the patient lies still on a table that moves through a donut-shaped scanner. Patients may experience a warm sensation or metallic taste when the contrast is injected, which is normal and temporary. It is essential to inform the healthcare provider about any allergies or medical conditions that may affect the safety of the procedure.
Overall, the decision to use a head CT with contrast should be made on a case-by-case basis, taking into account the individual patient's needs and medical history, and considering the potential risks and benefits of the procedure 1.
From the Research
Head CT with Contrast
- The use of noncontrast head computed tomography (CT) is common in emergency departments, but the use of contrast can be beneficial in certain situations 2.
- Iodinated contrast media is increasingly used in CT perfusion or angiographic examinations in acute stroke, but its use has not been shown to increase the risk of intracranial hemorrhage 3.
- In head trauma cases, CT is the modality of first choice, and the use of contrast can help identify subtle findings such as skull fractures and intracranial hemorrhage 4.
Indications for Contrast-Enhanced Head CT
- Contrast-enhanced head CT can be useful in evaluating patients with acute stroke, particularly those who have received intravenous thrombolysis 3.
- It can also be useful in head trauma cases, particularly when there is a high suspicion of intracranial hemorrhage or skull fracture 4.
- In some cases, contrast-enhanced head CT can help identify areas of blood-brain barrier disruption, which can be indicative of underlying pathology 5.
Interpretation of Contrast-Enhanced Head CT
- When interpreting contrast-enhanced head CT scans, it is essential to consider the clinical context and the patient's symptoms 2.
- The use of dual-energy CT can help differentiate between hemorrhage and contrast staining, which can be challenging to distinguish on non-contrast CT scans 5.
- A structured approach to reading head CT scans, including the use of a consistent search pattern, can help identify key findings that may warrant further specialist referral 6.