Abstract:

Objective Simple fingers weakness caused by small cortical infarction is rarely found in clinical practice. This study aimed to investigate the pathogenesis mechanism, clinical presentation and imaging features of such cases. 

Methods Outpatients with the main manifestation of fingers dysfunction caused by small cortical infarcts from Zhengzhou People’s Hospital from July 2009 to December 2016 were included in this study. The analyzed clinical data included sensory and moter functions in fingers, muscle strength of fingers (bending, stretching, adduction and outreach), and the possible pathogenesis mechanism or etiology in medical records. According to the predominant impaired fingers, the patients were divided into ulnar-lateral group and radial-lateral group. The locations of cerebral infarction were identified by diffusion weighted imaging. Based on the imaging, the distance from cerebral falx to lesion core (B) and distance from cerebral falx to the lateral margin of brain (A) were measured and the ration of B/A were calculated. 

Results A total of 13 cases with small cortex infarction were included, with 6 ones in ulnar-lateral group and 7 ones in radial-lateral group. B/A in ulnar-lateral group was (0.50±0.07), while B/A in radial-lateral group was (0.71±0.06), and the difference between the two groups had statistical significance (t =-5.67, P <0.05). The possible pathogenesis mechanism or etiology in ulnar-lateral group were as follows: large artery stenosis/impaired clearance of emboli in 5 cases and unexplained embolism in 1 case; and that in radial-lateral group were the following: artery-to-artery embolism in 4 cases, cardiogenic embolism in 2 cases, and Moyamoya disease in 1 case. 

Conclusions The simple impaired finger function is associated with small cortical infarction. The ulnar-lateral finger impairment is associated with medial cortex infarction, which may be associated with hypoperfusion. The radial-lateral finger impairment is associated with lateral cortex infarction, which may be associated with embolism.

Key words: Small cortical infarction; Finger dysfunction; Pathogenesis

摘要：

目的 以皮层小梗死引起单纯手指无力的临床表现较为少见，本文旨在探讨其发病机制、临床及影像学特点。 

方法 连续入选2009年7月-2016年12月来郑州人民医院就诊的以手指功能障碍为临床表现的皮层 小梗死患者，临床上记录患侧手部肌力、手部感觉异常情况及手指无力的详细查体（屈、伸、内收和 外展，依据0～5级肌力记录法），并记录患者可能的发病机制或病因，依据主要功能障碍手指为小指 或拇指分为主要尺侧手指功能障碍组和主要桡侧手指功能障碍组。影像学上应用弥散加权成像进 行病灶定位，并测量大脑镰至病变中心及大脑最外侧缘的距离（其比率定义为B/A）。 

结果 共入组符合标准的皮层小梗死患者13例，根据临床及影像学分析表明，主要累及尺侧手指 6例，主要累及桡侧手指7例。主要累及尺侧手指功能组B/A=0.50±0.07，主要累及桡侧手指功能组 B/A=0.71±0.06，两组比较差异有统计学意义（t =-5.67，P＜0.05）。主要累及尺侧手指功能组5例发 病机制为大动脉狭窄／栓子清除障碍，1例为不明原因栓塞；主要累及桡侧手指功能组4例发病机制主 要为动脉-动脉栓塞，2例为心源性栓塞，1例为烟雾病。 

结论 尺侧手指代表区靠近皮层内侧，梗死部位位于大血管分水岭区，发病机制可能与低灌注有 关。桡侧手指代表区靠近皮层外侧，梗死部位位于大脑皮层，发病机制可能与栓塞事件有关。

关键词: 皮层小梗死; 手指功能障碍; 发病机制