目的：探讨三维可变翻转角快速自旋回波序列（three dimensional sampling perfection with application optimized contrasts by using different flip angle evolution，3D-SPACE）神经成像技术显示腰骶丛肿瘤性病变的价值。方法：回顾性分析2018年1月至2023年12月间16例累及腰骶丛神经的肿瘤性病变患者的MRI资料，所有病例均经病理检查确诊。测量病灶的最大径，统计病灶数目，观察病变累及的腰骶丛神经位置，统计受累神经数目，描述肿瘤与神经间的关系。结果：16例患者中，单发病灶10例，多发病灶6例，病灶平均最大径为（57.1±37.2） mm。累及单根神经5例，累及多根神经11例。肿瘤与神经关系，沿神经生长5例，神经受压5例，神经受肿瘤侵袭、包绕6例。结论：3D-SPACE神经成像技术能清晰、直观地显示受累神经的位置、数目及肿瘤与神经间的关系，在显示腰骶丛肿瘤性病变的定位及诊断中具有重要价值。

Objective To investigate the value of the magnetic resonance neurography three-dimensional sampling perfection with application optimized contrasts by using different flip angle evolution (3D-SPACE) in displaying the neoplasms of the lumbosacral plexus. Methods MRI 3D-SPACE images of 16 cases with neoplasm in the lumbosacral plexus collected during January 2018 to December 2023 were retrospectively analyzed. All cases were confirmed by pathology. The maximum diameter of the tumors was measured and the number of lesions was counted. The location of the involved lumbosacral plexus was observed and the number of the involved nerves was counted. The relationship between the tumors and nerves was evaluated. Results Ten cases were of single lesion and 6 cases were of multiple lesions. The average maximum diameter of tumors was （57.1±37.2）mm. Single nerve involved was detected in 5 cases while multiple nerves involved were in 11 cases. The relationship between the tumor and nerve was divided into three types. The tumor grew along the nerve in 5 cases. The nerves were compressed by the tumors in 5 cases, and were invaded and surrounded in 6 cases. Conclusions MRI 3D-SPACE can reveal the location and numbers of the tumor, displaying the relationship between the tumor and nerve clearly and intuitively, which is important for localization and diagnosis of the neoplastm in the lumbosacral plexus.