Ⅰ型神经纤维瘤病周围神经病变的声像图表现

Ultrasonographic features of peripheral neuropathies in neurofibromatosis type Ⅰ

目的探讨Ⅰ型神经纤维瘤病（NF1）周围神经病变的声像图特征及分型。方法分析36例NF1周围神经病变的超声表现，并分析其病理意义。结果NF1周围神经病变（36例）为表现多样的神经纤维瘤，其高频声像图可分为四型：多发结节型、丛状型、弥漫型及混合型。多发结节型5例，肿瘤多发，呈椭圆形及分叶状，边界清晰，表现以低回声为主的混合性回声；丛状型12例，表现为肢体周围神经主干较长范围增粗，失去正常神经束结构，呈蔓丛状、串珠样低回声；弥漫型14例，肿瘤皮下浸润生长，皮下软组织明显增厚，结构紊乱，弥漫分布丛状及结节样低回声。混合型5例，周围神经病变为弥漫型及多发结节型神经纤维瘤并存，声像图兼具两型表现。结论NF1周围神经病变具有特征性声像图表现，与临床病理表现基本相符，有助于临床明确诊断并提供治疗依据。

Objective To investigate the ultrasonographic features corresponding to classification of peripheral neuropathies in neurofibromatosis type 1. Methods Thirty-six patients with peripheral neuropathies and diagnosis of neurofibromatosis type I were enrolled in this study. Ultrasound appearance of peripheral neuropathies was analyzed and divided into four groups according to their pathological classifications. There were 19 males and 17 females with age between 7 - 47 years. High frequency or board frequency ultrasound probes were used for scanning. Results The ultrasound findings were varied based on different pathological classifications. Multiple nodular class （n = 5） was presented as multiple nodes. Ultrasound demonstrated that tumors were multiple,oval or lobulated, and had well defined margin, and the echogenic of lesions was mainly hypoechoic. Plexiform class （ n = 12） was presented as cluster nodes along the peripheral nerve trunk. Ultrasound showed trunk nerves in extremities became thicker in a long range and lost the normal structure, and catenular or racemosum in shape. The echogenicity was hypoechoic. Diffuse class （ n = 14） was diffuse subcutaneous disease. Tumors range was infiltrative. The subcutaneous soft tissue was thicken and echogenicity was increased. The structure of nerve bundle was disturbed and associated with multiple hypoechoic nodes. Mixture class （ n = 5） was defined as mixture of multiple nodular class and plexiform class. In this group, diffuse disorders were co-existed with multiple nodes disorder. Conclusions The ultrasonographic appearances of peripheral nerve disorders in neurofibromatosis type I was closely corresponded to their pathological characters. And the ultrasonic examination would be helpful to diagnosis and provide important information for therapy.