摘要
BACKGROUND Diagnosis of a dementia subtype can be complex and often requires comprehensive cognitive assessment and dedicated neuroimaging.Clinicians are prone to cognitive biases when reviewing such images.We present a case of cognitive impairment and demonstrate that initial imaging may have resulted in misleading the diagnosis due to such cognitive biases.CASE SUMMARY A 76-year-old man with no cognitive impairment presented with acute onset word finding difficulty with unremarkable blood tests and neurological examination.Magnetic resonance imaging(MRI)demonstrated multiple foci of periventricular and subcortical microhaemorrhage,consistent with cerebral amyloid angiopathy(CAA).Cognitive assessment of this patient demonstrated marked impairment mainly in verbal fluency and memory.However,processing speed and executive function are most affected in CAA,whereas episodic memory is relatively preserved,unlike in other causes of cognitive impairment,such as Alzheimer’s dementia(AD).This raised the question of an underlying diagnosis of dementia.Repeat MRI with dedicated coronal views demonstrated mesial temporal lobe atrophy which is consistent with AD.CONCLUSION MRI brain can occasionally result in diagnostic overshadowing,and the application of artificial intelligence to medical imaging may overcome such cognitive biases.
