The 'Ear of Lynx Sign': A Radiodiagnostic Clue in Complicated Hereditary Spastic Paraplegia
Abstract
: Hereditary spastic paraplegia, also known as Strumpell-Lorrain disease, encompasses a group of hereditary neurological disorders characterized by progressive spasticity and lower limb weakness due to corticospinal tract degeneration. This condition can manifest clinically as a pure form with pyramidal signs or a complicated form exhibiting a spectrum of additional neurological and non-neurological manifestations. In this report, we present a compelling familial case of three male siblings, product of first-degree consanguinity, presented with complicated hereditary spastic paraplegia. The radiological evaluation of the case revealed noteworthy findings, including a thinning of the corpus callosum and an abnormal T2/FLAIR cone-shaped hyperintensity at the tip of the frontal horn of the lateral ventricles, resembling the tufts of hair crowning the ears of a lynx, termed the "ear of lynx sign." This unique radiological sign, combined with a thin corpus callosum, is commonly observed in genetic subtypes associated with mutations of the SPG11 and SPG15 genes. Considering the limited access and high cost of genetic studies in our region, the recognition and clinical importance of the 'Ear of Lynx Sign' take on utmost significance. This distinctive radiological clue plays a crucial role in early identification of genetic forms of hereditary spastic paraplegia, leading to better disease management, progression control, and overall enhancement of patients' clinical outcomes and quality of life. Our study underscores the significance of such radiodiagnostic signs, particularlyin areas withrestricted availabilityofgenetictesting,emphasizing theirprofoundimpacton patientcareandprognosis.
How to Cite This Article
Bano S, Nawaz A, Iqbal H, Numan A, Iftikhar S, Khawaja MAA, et al.. The 'Ear of Lynx Sign': A Radiodiagnostic Clue in Complicated Hereditary Spastic Paraplegia. J Pak Soc Intern Med. 2023;4(4):324–329. doi:10.70302/jpsim.v4i4.2366
Conflict of Interest
All authors declare no competing interests.
Funding
No specific funding was received for this research.
Funder information follows the Crossref Funder Registry standard.
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