Leukemic leptomeningeal carcinomatosis causing 4th and 6th nerve palsies

This is a 55-yo-man with CML that recurred as AML. Diagonal diplopia developed, and on examination he was found to have a partial right 6th nerve palsy, in addition to a left hypertropia that increased in right gaze, down gaze, and in left head tilt consistent with a left 4th nerve palsy. There was 10 degrees of excyclodeviation OS with double Maddox rod testing. MRI showed enhancement of the right 6th nerve, and he was ultimately diagnosed with leukemic leptomeningeal carcinomatosis. Upon looking down and to the right and left, there was a clear left superior oblique (SO) paresis. He also had a V-pattern esotropia, presumably given his right 6th NP left SO palsy, as the tertiary action of the SO muscle is abduction (V-pattern esodeviation is typically seen with bilateral 4th nerve palsies).