Dynamic nature of the CT angiographic “spot sign”

The "spot sign", first described in 2007, has shown that a focal area of contrast extravasation within an intracerebral haematoma (ICH) can be correlated with haematoma expansion. We describe a case where time-resolved dynamic CT angiography (dCTA) shows the appearance of the "spot sign" only in later images. This finding highlights the importance of timing of the static CT angiogram which, if performed too early, might result in a false-negative diagnosis.