FAST-AV or FAST-AB tool improves the sensitivity of FAST screening for detection of posterior circulation strokes


  • Conflict of interest: The authors have no financial interest or conflicts of interest.

Correspondence: Farhad Huwez, Department of Medicine, Southend University Hospital, Westcliffe on Sea, Essex, SS0 0RY, UK.


The simpler FAST tool (Face, Arms, Speech and Time to call 999 or emergency services) tool has been recommended to replace ROSIER (Recognition of Stroke in the Emergency Room) screening for initial assessment of patients with suspected acute stroke [1]. The FAST, however, fails to detect a significant number of patients with posterior fossa strokes, especially those with ataxia and visual disturbances [2]. The ABCD-E2 screening tool [Ataxia, Blindness (unilateral/bilateral), Consciousness, Dysphagia, Eye 1 (Diplopia), Eye 2 (Pupillary abnormalities)] has been suggested to identify patients in the emergency department with features of posterior circulation stroke [3, 4], but it may lack specificity. Therefore, we suggested that the incorporation of ataxia and visual symptoms to FAST screening [FAST-ataxia and visual disturbance (AV) or FAST-ataxia and blindness (AB)] may increase its sensitivity for detection of acute posterior circulation strokes.

We reanalyzed 35 consecutive stroke patients admitted to the Stroke Unit at Basildon Hospital [4] including their initial presentations, screening tools, and radiological diagnoses. There were 10 men and 25 women with a mean age of 79·6 years (range 58–99).

The presenting features included limb weakness (48·5%), speech abnormality (45·7%), facial weakness (22·8%), disturbed consciousness (11·4%), collapse (11·4%), visual disturbance (8·6%), dizziness (8·6%), confusion (5·7%), incoordination/ataxia (5·7%), and paraesthesia (2·9%).

The FAST screening was documented for 85·7% of patients by paramedics but ROSIER was not recorded in A&E (Accident & Emergency Department) or medical notes.

FAST was positive in 24 (68·5%) patients, while 11 (31·4%) were FAST negative. Among FAST negative patients, three presented with ataxia and two with blurred vision. Therefore, FAST-AV or FAST-AB screening would have been positive in 29/35 (83·8%) of the patients, 14% more than when using FAST tool alone.

Therefore, we believe that the addition of AV or AB to the FAST tool would certainly increase its sensitivity for early recognition of strokes (or transient ischemic attacks) affecting the posterior circulation. Larger prospective studies are needed.