Table 1.

Criteria for bone marrow fibrosis grading.

Grading	Description
MF-0	no reticulin fibers corresponding to normal bone marrow
MF-0.5	focal areas with a loose network of reticulin with many intersections alternated with areas with no reticulin fibers
MF-1	loose network of reticulin with many intersections evenly distributed over the entire length of the femurs
MF-1.5	focal areas with a diffuse and dense increase in reticulin with extensive intersections
MF-2	diffuse and dense increase in reticulin with extensive intersections evenly distributed over the entire length of the femurs, occasionally with only focal bundles of collagen and/or focal osteosclerosis
MF-3	diffuse and dense increase in reticulin with extensive intersections with coarse bundles of collagen, often associated with significant osteosclerosis