Cranial computed tomography and TIA

Transient ischaemic attack (TIA) is a focal neurological deficit of vascular deficit of vascular etiology, the evidence of which completely resolves within 24 hours. TIAs were thought to cause no permanent damage to the brain before the introductionof cranial computed tomography (CCT) in 1975. Thereafter, some patients with typical TIA were found to have had cerebral infarction. Though CCT has been extensively used for establishing the diagnosis of TIA and stroke, the factors determining infarctionand prognostic significance of CCT abnormalities has not been analysed. Variables such as image quality, generation of CCT equipment, duration of the TIA, timing of CCT in relation to the event, territory of TIA, degree of arterial stenosis, plaque characteristics, age of the patient - all affect the likelihood of unrecognized (silent) cerebral infarction. The chance of secondary stroke and premature vascular death are increased, if silent infarction is found.