Mallinckrodt Institute of Radiology, Washington University School of Medicine, St. Louis, MO 63110, USA.
AJNR Am J Neuroradiol. 2013 Jul;34(7):1438-42. doi: 10.3174/ajnr.A3388. Epub 2013 Jan 31.
Changes at the optic nerve head on DWI in the presence of papilledema have not been systematically studied. The purpose of this study was to evaluate if hyperintensity of ON heads on DWI is associated with papilledema.
In this retrospective study, 19 patients (4 men, 15 women; median age, 32 years) with papilledema and 20 control participants (7 men, 13 women; median age, 48 years) who had undergone prior MR imaging of the brain were identified. Two neuroradiologists blinded to the diagnosis independently reviewed the DWI for the presence of hyperintense signal at the ON head of each eye. If present, they graded the signal as mild or prominent. Groups with and without papilledema were compared for the prevalence of ON head hyperintensity by using the Fisher exact test, with analyses performed both for groups of patients and for individual eyes. Presence of ON head hyperintensity was also studied as a function of Frisen papilledema grade on fundoscopy, when available.
Hyperintensity of the ON heads on DWI was significantly associated with papilledema (P = .001). For the 2 readers, hyperintensity at both ON heads was 26.3% and 42.1% sensitive and 100% specific in the detection of papilledema. The presence of unilateral ON head hyperintensity was not specific for papilledema and was invariably graded as mild when seen in the control group. Patients with higher papilledema grades had a higher prevalence of hyperintensity at the ON heads.
Hyperintensity of the ON heads on DWI can serve as a useful imaging marker for papilledema, especially if bilateral. Its absence, however, does not exclude papilledema.
视盘头部在弥散加权成像（DWI）上的变化在伴有视乳头水肿的情况下尚未得到系统研究。本研究旨在评估视盘头部 DWI 上的高信号是否与视乳头水肿相关。
在这项回顾性研究中，共纳入 19 例（4 名男性，15 名女性；中位年龄 32 岁）伴有视乳头水肿的患者和 20 例（7 名男性，13 名女性；中位年龄 48 岁）经先前脑部 MRI 检查的对照参与者。两名神经放射科医生在不知道诊断的情况下，独立地对 DWI 进行了视神经头部存在高信号的审查。如果存在，则对信号进行轻度或显著分级。使用 Fisher 精确检验对有和无视乳头水肿的组进行视神经头部高信号的患病率比较，分析同时针对患者组和个体眼睛进行。当存在时，还研究了视神经头部高信号的存在作为眼底镜 Frisen 视乳头水肿分级的函数。
视神经头部 DWI 上的高信号与视乳头水肿显著相关（P=.001）。对于 2 名读者，视神经头部的高信号在检测视乳头水肿方面的敏感性分别为 26.3%和 42.1%，特异性均为 100%。单侧视神经头部高信号的存在对视乳头水肿不具有特异性，并且在对照组中始终被评为轻度。视乳头水肿程度较高的患者视神经头部高信号的患病率更高。
视神经头部 DWI 上的高信号可以作为视乳头水肿的有用成像标志物，尤其是双侧存在时。然而，其不存在并不能排除视乳头水肿。
