Fibrolipomatous hamartoma of the nerve
A fibrolipomatous hamartoma of the nerve (also known as a neural fibrolipoma) is a benign neoplasm of nerves, resulting from anomalous growth of fibroadipose tissue of the nerve sheath.
Fibrolipomatous hamartoma may be related to hypertrophy of mature fat and fibroblasts in the epineurium
A fibrolipomatous hamartoma of the nerve can involve the median (80%), ulnar and or radial nerves and or dorsum of the hand.
Macrodactyly of the involved part can be present in ~ 66% of all cases of fibrolipomatous hamartoma of the median nerve.
A characteristic hypoechoic coaxial cabling encased by an echogenic substratum may be seen 3.
MRI features are often pathognomonic and typically shows a coaxial cable-like appearance on axial images and a spaghetti-like appearance on coronal images 2,6.
- T1 - the neural bundles were hyperintense to muscle and the surrounding substratum was isointense to muscle 3
- T2 - fat components are high signal and fibrous components are low signal
It is thought to have been first reported by M L Mason in 1953 5.
Treatment and prognosis
The lesion is benign and the preferred management of the lesion is conservative.
- 1. Silverman TA, Enzinger FM. Fibrolipomatous hamartoma of nerve. A clinicopathologic analysis of 26 cases. Am. J. Surg. Pathol. 1985;9 (1): 7-14. - Pubmed citation
- 2. Jain TP, Srivastava DN, Mittal R et-al. Fibrolipomatous hamartoma of median nerve. Australas Radiol. 2007;51 Spec No. : B98-B100. doi:10.1111/j.1440-1673.2007.01790.x - Pubmed citation
- 3. Toms AP, Anastakis D, Bleakney RR et-al. Lipofibromatous hamartoma of the upper extremity: a review of the radiologic findings for 15 patients. AJR Am J Roentgenol. 2006;186 (3): 805-11. doi:10.2214/AJR.04.1717 - Pubmed citation
- 4. Murphey MD, Carroll JF, Flemming DJ et-al. From the archives of the AFIP: benign musculoskeletal lipomatous lesions. Radiographics. 24 (5): 1433-66. doi:10.1148/rg.245045120 - Pubmed citation
- 5. Mason ML. Presentation of cases. Proceedings of the American Society of Surgery of the Hand. J Bone Joint Surg Am. 1953 Jan 1;35A(1):273–275.
- 6. Chiang CL, Tsai MY, Chen CK. MRI diagnosis of fibrolipomatous hamartoma of the median nerve and associated macrodystrophia lipomatosa. J Chin Med Assoc. 2010;73 (9): 499-502. doi:10.1016/S1726-4901(10)70107-6 - Pubmed citation
- 7. Ha JF, Teh BM, Abeysuriya DT et-al. Fibrolipomatous hamartoma of the median nerve in the elbow: a case report. Ochsner J. 2012;12 (2): 152-4. Free text at pubmed - Pubmed citation