case_images: PMC7227760_01
case_images: Patient 1 showing bilateral drooping of eyelids
case_images: JPN-15-45-g001.jpg
case_images: PMC7227760_01_JPN-15-45-g001.jpg
case_images: F1
case_images: Examination revealed optic atrophy in both eyes [Figure 1].
case_images: Histopathology shows (A) normal eosin and hematoxylin stain, (B) Gomori's trichrome normal stain, (C) normal succinic dehydrogenase, and (D) no Cytochrome C oxidase-deficient fibers
case_images: JPN-15-45-g002.jpg
case_images: PMC7227760_01_JPN-15-45-g002.jpg
case_images: F2
case_images: Electro myography showed myopathic pattern and left biceps biopsy showed normal architecture, including modified Gomori's trichrome stain [Figure 2].
case_images: Values of complexes in respiratory chain values revealing severe complex 1 deficiency
case_images: JPN-15-45-g003.jpg
case_images: PMC7227760_01_JPN-15-45-g003.jpg
case_images: F3
case_images: However respiratory chain assay showed severe complex 1 deficiency [Figure 3].
case_images: Preoperative MRI of patient 1 showing (A) retroflexed odontoid, (B) arachnoid cyst in thoracic region, (C) spinal cord pushed anteriorly and laterally, and (D) tethered cord
case_images: JPN-15-45-g004.jpg
case_images: PMC7227760_01_JPN-15-45-g004.jpg
case_images: F4
case_images: Magnetic resonance imaging (MRI) showed retroflexed dens with cervicomedullary compression, poorly developed anterior arch of atlas, brachycephaly, long arachnoid cyst with dural ectasia from cervical to lumbar region with anterior displacement of cord, and low lying cord tethered at L4 [Figure 4].
case_images: (A) Cord atrophy. (B) Partly decompressed lumbar cord. (C) Partly decompressed thoracic cord
case_images: JPN-15-45-g005.jpg
case_images: PMC7227760_01_JPN-15-45-g005.jpg
case_images: F5
case_images: He underwent lumbar drain placement, L2 left hemilaminectomy, and repair of dural defect, and at 2 months of follow-up, he is presently ambulant, and his postoperative imaging showed significant relief of compression [Figure 5].
case_images: Patient 2 showing dysmorphic features without ptosis
case_images: JPN-15-45-g006.jpg
case_images: PMC7227760_01_JPN-15-45-g006.jpg
case_images: F6
case_images: He did not undergo muscle biopsy; however, his MRI showed similar features [Figures 6 and 7].
case_images: MRI of patient 2 showing (A) retroflexed odontoid, (B) arachnoid cyst in dorsal cord, (C) arachnoid cyst extending along root sleeves, and (D) arachnoid cyst in lumbar region
case_images: JPN-15-45-g007.jpg
case_images: PMC7227760_01_JPN-15-45-g007.jpg
case_images: F7
case_images: He did not undergo muscle biopsy; however, his MRI showed similar features [Figures 6 and 7].