Six manual measures of distance and area
| Measure | How to Measure |
|---|---|
| Biparietal width | Greatest distance between left and right parietal cortices, measured on a single coronal slice identifying bilateral  cochlea and basilar truncus |
| Interhemispheric distance | Distance between crowns of superior frontal gyri, measured on the same coronal slice as biparietal width |
| Callosal thickness | Thinning at the genu, midbody, splenium |
| Transcerebellar diameter | Single coronal slice at level of ventricular atrium |
| Lateral ventricular diameter | Same coronal slice as transcerebellar diameter |
| Deep grey matter area | Single axial slice showing caudate heads, lentiform nuclei, and thalami |