Cerebral Circulation During Treatment of Blood-Injury Phobia: A Case Study

A case of blood-injury phobia complicated by fainting is described. Measures of cerebral blood flow velocity (CBFV) and heart rate (HR) indicated that phobic exposure reliably precipitated a marked drop in CBFV, simultaneous with an increase in HR and onset of dizziness. It is suggested that hyperventilation was a factor exacerbating fainting in this case. Muscle tensing produced small increases in cerebral blood flow velocity but these were not of sufficient magnitude to prevent onset of dizziness. The patient improved with treatment involving graded exposure, respiratory control and muscle tensing. At seven months follow-up the patient maintained improvements in anxiety and avoidance but again became faint during exposure.