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A case of intraneural perineurioma presenting with monomelic atrophy in a child
Ayako Miyahara-Katayama1, Yasushi Ohya, Tsuyoshi Omi
1Department of Child Neurology, National Center of Neurology and Psychiatry (NCNP), Masayuki Sasaki, 4-1-1 Ogawahigashi-cho, Kodaira, Tokyo 187-8551, Japan.
Insights
This case study details an 11-year-old girl with progressive leg atrophy due to a rare intraneural perineurioma. This finding highlights the importance of considering this nerve tumor in pediatric cases of monomelic weakness.
Area of Science:
- Neurology
- Oncology
- Pediatrics
Background:
- Intraneural perineurioma is a rare nerve sheath tumor, often affecting young individuals.
- Early diagnosis is crucial for managing pediatric neurological conditions.
Observation:
- An 11-year-old girl presented with progressive atrophy of her left lower extremity, noted since age 7.
- Imaging revealed muscle atrophy and low-density areas in the left leg, with sciatic nerve enhancement.
- Sural nerve biopsy showed pseudo-onion bulbs, positive for epithelial membrane antigen, indicative of perineurioma.
Findings:
- Histopathology confirmed intraneural perineurioma, characterized by nerve fibers surrounded by perineurial cells.
- The tumor extended from the nerve root to the ankle, representing the longest reported case.
- This diagnosis was made in the context of a pre-existing mild dilated cardiomyopathy.
Implications:
- Intraneural perineurioma should be considered in the differential diagnosis of children presenting with unilateral limb weakness or atrophy.
- This case underscores the extensive nerve involvement possible with intraneural perineurioma.
- Further research into the etiology and optimal management of pediatric intraneural perineurioma is warranted.
Abstract:
We report the case of an 11-year-old girl who developed slowly progressive atrophy of the left lower extremity. She suffered from mild dilated cardiomyopathy of unknown cause since 4years of age. When she was 7years old, her family noticed that her left extremity was thinner compared to the right one. Computed tomography showed atrophy and areas of low density in the left gluteus maximus, thigh, and calf muscles. The left sciatic nerve showed gadolinium enhancement on magnetic resonance imaging. A biopsy of the left sural nerve revealed pseudo-onion bulbs. Immunohistochemical staining was positive for epithelial membrane antigen and negative for S100 protein. Electron microscopy demonstrated myelinated or unmyelinated nerve fibers surrounded by concentric layers of perineurial cells. These results indicated intraneural perineurioma. The tumor was estimated at least from the nerve root to the ankle joint. The length of nerve involvement in this patient was the highest recorded in the literatures. Intraneural perineurioma is a very rare disorder, but is tend to be found in youth. This disorder should be considered when we see children with monomelic weakness and/or atrophy.