Bijbij Aymane, Remmal Adib, Bellamlih Habib, Africha Taoufik, Belabbes Soufiane, Zainoun Brahim
Service de Radiologie, Hôpital Militaire Moulay Ismail, Meknès. Sidi Mohamed Ben Abdellah University, Fez, Maroc.
Radiol Case Rep. 2024 Nov 15;20(1):837-840. doi: 10.1016/j.radcr.2024.09.158. eCollection 2025 Jan.
Hereditary spastic paraplegias represent a rare set of monogenic disorders encompassing 79 distinct genetic variations. The principal culprit behind recessive hereditary spastic paraplegia is frequently attributed to mutations in the spastic paraplegia gene, particularly type 11, closely followed by type 15. This category is typically characterized by nonspecific clinical features, including cognitive decline, which may precede the development of progressive lower limb weakness and spasticity. While the thinning of the spinal cord is recognized as the magnetic resonance imaging hallmark of hereditary spastic paraplegia, insights into specific subtypes can be gleaned from brain magnetic resonance imaging findings. Notably, thinning of the corpus callosum emerges as a prominent abnormality in almost one-third of recessive hereditary spastic paraplegias, providing pertinent diagnostic clues. Additionally, recent observations introduce a distinctive anomaly termed the "ears of the lynx" sign, primarily affecting the forceps minor of the corpus callosum. This sign is highly indicative of type 11 and 15 hereditary spastic paraplegias. We present the case of a patient diagnosed with hereditary spastic paraplegia type 15 through exome genetic testing, with the initial magnetic resonance imaging revealing the characteristic "ears of the lynx" sign.
遗传性痉挛性截瘫是一组罕见的单基因疾病，包含79种不同的基因变异。隐性遗传性痉挛性截瘫的主要病因通常归因于痉挛性截瘫基因的突变，尤其是11型，其次是15型。这类疾病的典型特征是临床表现不具特异性，包括认知功能下降，这可能先于进行性下肢无力和痉挛的出现。虽然脊髓变薄被认为是遗传性痉挛性截瘫的磁共振成像特征，但通过脑磁共振成像结果可以了解特定亚型的情况。值得注意的是，胼胝体变薄在近三分之一的隐性遗传性痉挛性截瘫中表现为突出异常，提供了相关诊断线索。此外，最近的观察发现了一种独特的异常，称为“猞猁耳”征，主要影响胼胝体的小钳。该征象高度提示11型和15型遗传性痉挛性截瘫。我们报告一例通过外显子组基因检测诊断为15型遗传性痉挛性截瘫的患者，其最初的磁共振成像显示出特征性的“猞猁耳”征。
