Smoker's criteria

Smoker’s criteria use three quantitative measures of basilar artery morphology to diagnose dolichoectasia: 

• laterality
• bifurcation height
  • ​surrogate measures for tortuosity and elongation
• basilar artery diameter represents the degree of dilatation

The application of Smoker’s criteria provides a means to diagnose dolichoectasia of the basilar artery ^1,2. Elongation is indicated by abnormal laterality or height, ectasia is indicated by abnormal diameter, and doliechoectasia is indicated by the presence of both elongation and ectasia ⁶.

Criteria

Basilar artery diameter

Score of 1 is abnormal:

• 0: 1.9–4.5 mm
• 1: >4.5 mm

Laterality

Score ≥2 is abnormal:

• 0: midline throughout
• 1: medial to the lateral margin of the clivus or dorsum sellae
• 2: lateral to lateral margin of clivus or dorsum sellae
• 3: at the cerebellopontine angle

Height of bifurcation

Score ≥2 is abnormal:

• 0: at or below the dorsum sellae
• 1: within the suprasellar cistern (one cut above dorsum)
• 2: at the 3^rd ventricle floor (one cut above suprasellar cistern)
• 3: indenting and elevating the floor of the 3^rd ventricle (two or more cuts above suprasellar cistern)

The above criteria were defined on 5 mm thick slices ¹.

History and etymology

Wendy R K Smoker (fl. 2020) is an American neuroradiologist who developed her eponymous criteria in the mid-1980s ^1,2.