肥大性下橄榄核变性的MRI诊断

目的 分析继发于中脑及桥脑被盖束病变的肥大性下橄榄核变性（HOD）的MRI表现。以提高对该病7变的认识，资料与方法 回顾分析7例继发于脑干病变的HOD者的MRI表现，其中原发病变为血管畸形4例，高血压病脑干出血2例。颅脑外伤1例。结果 脑干病变后最早1个月出现下橄榄核信号异常，8个月显示最清晰，MRI表现为T2WI高信号，T1WI呈等或稍低信号，均位于原发病变的同侧下橄榄核。结论 桥脑及中脑被盖束病变可以引起同侧下橄榄核发生肥大性变性。MRI可以清晰显示HOD病变，可提高对该病变的认识。避免误诊。

MRI Diagnosis of Hypertrophic Degeneration of Olivary Nucleus

Objective To analyze MR appearance of hypertrophic olivary degeneration (HOD) secondary to lesions of brainstem or pons tegmental tract, and to make a further understanding of this disease.Materials and Methods MRI findings in 7 patients with HOD were retrospectively analyzed. HOD was secondary to arterial venous malformation (n=4), brainstem hemorrhage due to hypertension (n=2) or craniocerebral injury (n=1).Results Abnormal signal in inferior olivary nucleus appeared as early as one month after the brainstem was diseased, which became most apparent in 8 months. HOD presented as high intensity signal on T 2WI and iso or hypo intensity signal on T 1WI. All HOD lesions were located in the inferior olivary nucleus at the same side of the primary disease. Conclusion Hypertrophic degeneration of olivary nucleus can be caused by the lesions of brainstem or pons tegmental tract at the same side. MRI can clearly demonstrate HOD, thus, improve its diagnosis.