Hypertrophic olivary degeneration (HOD) is a rare phenomenon that occurs after various insults to the Guillain-mollaret triangle (GMT). HOD is unique because the degeneration of inferior olivary nucleus becomes hypertrophic rather than atrophic. In this study, a 31-year-old woman developed HOD after pontine cavernoma surgery had been performed. The clinical manifestation was involuntary intorsion of right lower extremity during walking, which has not been reported in the literature. The woman also presented with palatal tremor, the most classic symptom of HOD. HOD's imaging trait include olive hypertrophy with increased T2 signal intensity on MRI, which are corresponding to the pathological findings. HOD is a self-limiting disease and excessive treatments are unnecessary.

肥厚性橄榄色变性（HOD）是一种罕见的现象，发生在对吉兰-莫拉利特三角（GMT）的各种侮辱之后。HOD之所以独特，是因为下橄榄核的变性变得肥大而不是萎缩。在这项研究中，一名31岁妇女在进行了脑桥海绵状瘤手术后出现了HOD。临床表现为行走过程中右下肢非自愿性侵犯，文献中尚未报道。该妇女还表现出震颤，这是HOD最典型的症状。HOD的影像学特征包括橄榄肥大，MRI上的T2信号强度增加，这与病理结果相对应。HOD是一种自限性疾病，不需要过度治疗。