Department of Radiology, University of Michigan Health System, 1500 E Medical Center Dr, B2 A209P, Ann Arbor, MI 48109, USA.
Radiology. 2013 Jun;267(3):727-34. doi: 10.1148/radiol.12121508. Epub 2013 Jan 29.
To determine whether the intravenous administration of low-osmolality contrast material is associated with exacerbation of disease-related symptoms in patients with myasthenia gravis.
This HIPAA-compliant, retrospective cohort study was approved by the institutional review board. The requirement to obtain patient consent was waived. Computed tomography (CT) was performed in 267 patients with clinically confirmed myasthenia gravis between January 1, 1995, and December 31, 2011. CT was performed without intravenous administration of contrast material in 155 patients and with intravenous administration of low-osmolality contrast material in 112. Electronic medical records were searched to identify myasthenia gravis-related symptoms before (≤ 14 days) and after (≤ 45 days) each CT examination. The Mantel-Cox log-rank test was used to compare the time to symptom progression between the two groups. The Fisher exact test was used to compare rates of disease-related symptoms during three time periods: (a) 0-1 day after CT, (b) 2-7 days after CT, and (c) 8-45 days after CT.
The unenhanced and contrast-enhanced CT groups had similar thymectomy rates (P = .97) and disease-related symptom trends before CT (P = .58). The contrast-enhanced CT group was associated with a significant reduction in time to disease-related symptom progression following CT (median time to onset of symptom progression, 2.5 days with contrast-enhanced CT vs 14.0 days with unenhanced CT; P = .05). There were significantly more disease-related symptom exacerbations within 1 day of CT in the contrast-enhanced CT group compared with the unenhanced CT group (6.3% [seven of 112 patients] vs 0.6% [one of 155 patients], respectively; P = .01). Acute exacerbations were primarily respiratory (five patients with new-onset dyspnea [four in contrast-enhanced CT group and one in unenhanced CT group], two patients with progressive dyspnea [both in the contrast-enhanced CT group], and one patient with progressive weakness [in contrast-enhanced CT group]). There was no difference in symptoms between groups at 2-7 days (P = .70) or 8-45 days (P = .99).
Intravenous administration of low-osmolality contrast material is significantly associated with exacerbation of myasthenia gravis-related symptoms. Exacerbations most commonly manifest as new or progressive acute respiratory compromise.
确定在患有重症肌无力的患者中，静脉内给予低渗透压造影剂是否会加重与疾病相关的症状。
这项符合 HIPAA 规定的回顾性队列研究得到了机构审查委员会的批准。豁免了获得患者同意的要求。1995 年 1 月 1 日至 2011 年 12 月 31 日期间，对 267 例经临床确诊的重症肌无力患者进行了计算机断层扫描（CT）检查。155 例患者未行静脉内给予造影剂的 CT 检查，112 例患者行静脉内给予低渗透压造影剂的 CT 检查。检索电子病历以确定每次 CT 检查前（≤14 天）和后（≤45 天）与重症肌无力相关的症状。采用 Mantel-Cox 对数秩检验比较两组之间症状进展的时间。采用 Fisher 确切概率法比较 CT 后 3 个时间段（a）0-1 天，（b）2-7 天，（c）8-45 天内疾病相关症状的发生率。
未增强 CT 组和增强 CT 组的胸腺切除术率相似（P =.97），且 CT 前疾病相关症状趋势相似（P =.58）。增强 CT 组 CT 后与疾病相关症状进展的时间明显缩短（出现症状进展的中位时间，增强 CT 组为 2.5 天，未增强 CT 组为 14.0 天；P =.05）。与未增强 CT 组相比，增强 CT 组 CT 后 1 天内疾病相关症状恶化的发生率显著更高（分别为 6.3%[112 例患者中 7 例]和 0.6%[155 例患者中 1 例]；P =.01）。急性恶化主要是呼吸系统（5 例患者出现新发呼吸困难[增强 CT 组 4 例，未增强 CT 组 1 例]，2 例患者出现进行性呼吸困难[均在增强 CT 组]，1 例患者出现进行性肌无力[增强 CT 组]）。两组在 2-7 天（P =.70）或 8-45 天（P =.99）时症状无差异。
静脉内给予低渗透压造影剂与重症肌无力相关症状的加重显著相关。恶化最常见的表现为新发或进行性急性呼吸功能障碍。
