 There is mixed response to therapy with increasing number of enhancing lesions in the cerebellum, and decreasing size of pre-existing supratentorial enhancing lesions. In the cerebellum, there are greater than 10 punctate foci of enhancement in the bilateral middle cerebellar peduncles and in the inferior cerebellar hemispheres today as compared to less than 6 lesions on the prior exam (series 13 images 38 -- 56). Many of these lesions show associated punctate foci of T2 hyperintense signal.In the supratentorial brain there is interval decrease in size/prominence of the enhancing lesions. For example, there is a punctate lesion in the right periatrial white matter on series 13 image 90 which measured 5 mm previously. A punctate right basal ganglia lesion on series 13 image 100 measured 4 mm previously. A punctate left parietal subcortical lesion on series 13 image 104 measured up to 7 mm previously. A cluster of small enhancing lesions in the left superior frontal gyrus is less prominent on current exam. However, on series 13 image 134, there is a small focus of enhancement in the left posterior frontal lobe medially measuring up to 3 mm, not clearly present on the prior examination, and suspected to be new.There is no acute infarct, mass effect or midline shift. There is no hydrocephalus.There is persistent moderate left mastoid and mild ethmoid sinus mucosal thickening.
Mixed response to interval therapy with increasing number of punctate cerebellar lesions and decreasing size of pre-existing supratentorial lesions. A 3-mm posterior left frontal lobe enhancing lesion is not definitely present on the prior exam, and is suspected to be new.