Division of Surgical Oncology, Department of Surgery, University of Louisville, 315 E. Broadway - M10 - Rm#312, Louisville, KY, 40202, USA.
Biomedical Engineering Laboratory, University of Louisville, 315 E. Broadway - M10 - Rm#312, Louisville, KY, 40202, USA.
Surg Endosc. 2017 Dec;31(12):5076-5082. doi: 10.1007/s00464-017-5571-4. Epub 2017 Apr 25.
The optimal use of esophageal stents for malignant and benign esophageal strictures continues to be plagued with variability in pain tolerance, migration rates, and reflux-related symptoms. The aim of this study was to evaluate the differences in radial force exhibited by a variety of esophageal stents with respect to the patient's esophageal stricture.
Radial force testing was performed on eight stents manufactured by four different companies using a hydraulic press and a 5000 N force gage. Radial force was measured using three different tests: transverse compression, circumferential compression, and a three-point bending test. Esophageal stricture composition and diameters were measured to assess maximum diameter, length, and proximal esophageal diameter among 15 patients prior to stenting.
There was a statistically significant difference in mean radial force for transverse compression tests at the middle (range 4.25-0.66 newtons/millimeter N/mm) and at the flange (range 3.32-0.48 N/mm). There were also statistical differences in mean radial force for circumferential test (ranged from 1.19 to 10.50 N/mm, p < 0.001) and the three-point bending test (range 0.08-0.28 N/mm, p < 0.001). In an evaluation of esophageal stricture diameters and lengths, the smallest median diameter of the stricture was 10 mm (range 5-16 mm) and the median proximal diameter normal esophagus was 25 mm (range 22-33 mm), which is currently outside of the range of stent diameters.
Tested stents demonstrated significant differences in radial force, which provides further clarification of stent pain and intolerance in certain patients, with either benign or malignant disease. Similarly, current stent diameters do not successfully exclude the proximal esophagus, which can lead to obstructive-type symptoms. Awareness of radial force, esophageal stricture composition, and proximal esophageal diameter must be known and understood for optimal stent tolerance.
在恶性和良性食管狭窄的治疗中，食管支架的最佳使用仍然存在患者疼痛耐受度、迁移率和反流相关症状的差异。本研究旨在评估各种食管支架的径向力差异，并与患者的食管狭窄有关。
使用液压机和 5000N 力计对四家制造商生产的 8 种支架进行径向力测试。使用三种不同的测试方法测量径向力：横向压缩、圆周压缩和三点弯曲测试。在支架置入前，对 15 名患者的食管狭窄成分和直径进行测量，以评估最大直径、长度和近端食管直径。
在横向压缩测试的中间（范围 4.25-0.66 牛顿/毫米 N/mm）和法兰处（范围 3.32-0.48 N/mm）的平均径向力存在统计学显著差异。圆周测试（范围从 1.19 到 10.50 N/mm，p < 0.001）和三点弯曲测试（范围 0.08-0.28 N/mm，p < 0.001）的平均径向力也存在统计学差异。在评估食管狭窄直径和长度时，狭窄的最小中位数直径为 10mm（范围 5-16mm），近端正常食管的中位数直径为 25mm（范围 22-33mm），目前超出了支架直径的范围。
测试的支架在径向力方面表现出显著差异，这进一步阐明了某些患者的支架疼痛和不耐受，无论是良性还是恶性疾病。同样，目前的支架直径不能成功地排除近端食管，这可能导致阻塞型症状。为了获得最佳的支架耐受性，必须了解和理解径向力、食管狭窄成分和近端食管直径。
