??? ??? ?? ? ? ?? ?? ??? ????? ??? ?? ??? ???? ??? ???? ?????.???? ??? ? ?? ??: ??? ??? ???? ???? ??? ? ????.A variant of ependymoma, normally found in the spinal twine, with tumor cells organized in fascicles of variable width and cell density.By adolescence, all persons with MLIV have serious visual impairment. A neurodegenerative ingredient of M