TPP1 and mitochondrial disease: In our study, brain MRI abnormalities were mainly seen in TPP1, GBA, MFSD8, and mt-DNA mutations, which were unrelated to photosensitivity but related to the disease itself (e.g., progressive parenchymal atrophy caused by NCLs, abnormal signals in the cerebral cortex caused by mitochondrial disease) (4, 12).