Table 3.

Tissue blocks and regions for staging of pTDP-43 pathology in ALS

Stage 1:	block 1: agranular motor neocortex – Brodmann areas 4, 6 block 2: medulla oblongata at the level of N. XII – bulbar somatomotor neurons of N. XII optional: spinal cord layer 9 – ventral horn α-motoneurons
Stage 2:	block 1 block 2: inferior olive, medullary reticular formation optional: parvocellular portion of the red nucleus
Stage 3:	blocks 1 and 2 block 3: prefrontal neocortex (e.g., gyrus rectus, orbital gyri) block 4: striatum optional: postcentral neocortex
Stage 4:	blocks 1-4 block 5: hippocampal formation, entorhinal region, adjoining temporal neocortex

Staging is based on a minimum of five tissue blocks, additional blocks, e.g., from the spinal cord or midbrain, are optional. When assigning stages, the extent (topographical distribution pattern) is accorded more weight than the degree (severity) of the pTDP-43 pathology in each region.