a) List the common CT and MRI features of severe hypoxic ischaemic encephalopathy (HIE) that appear after 72 hours. (40% marks)
b) Outline how neuro-imaging findings may assist in prognostication for HIE. (60% marks)
What was required to score well in this question was an understanding of positive and negative predictive value of these imaging modalities, and how they need to be used and interpreted in conjunction with other prognostication tests. Many candidates mentioned a multimodal prognostic model, however, they failed to elaborate on how they are utilised in a multimodal approach.
If "what was required to score well in this question was an understanding of positive and negative predictive value", then perhaps the words "positive and negative predictive value" should have appeared in the stem, otherwise it would seem unfair to expect the exam candidates to guess their way to the optimum marks. Still, one may be able to argue that the stem is about diagnostic tests, and is phrased in a way that leads naturally to the discussion of their validity, of which NPV and PPV are an important part.
a)
CT features of hypoxic ischaemic encephalopathy:
MRI features of hypoxic ischaemic encephalopathy:
b)
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