Multiple Brain Abscesses due to Streptococcus anginosus: Prediction of Mortality by an Imaging Severity Index Score
Table 4
Image severity index score [3] and proposed modifications in italic letters.
Parameters
Points
Number (single, multilocular, or attached to each other like a bunch of grapes = 1; score increased for every additional abscess)
Solitary
1
Multiple
2–6
Location (superficial: cerebral, cerebellar hemispheres; deep: basal ganglia, thalamus, corpus callosum, brain stem, vermis, and within ventricles; extensive or combined: both superficial and deep)
Superficial
1
Deep
2
Empyema
3
Ventriculitis
4
Combined
5
Diameter (large diameter of abscess in transverse plane on CT and MRI; largest diameter of multilocular abscess is the largest diameter of the abscess taken as a whole)
<2 cm
1
2–4 cm
2
>4 cm
3
Perilesional edema (surrounding edema observed as high signal intensity on T2 weighted MRI image or hypodensity on CT image. For multiple abscesses, highest for edema was used)
Minimal (maximum thickness < radius of abscess)
1
Moderate (maximum thickness between the radius and diameter of abscess)
