Section of Neuroradiology, Division of Diagnostic Imaging, Sheba Medical Center, Ramat-Gan, Israel.
Sackler School of Medicine, Tel Aviv University, Tel Aviv, Israel.
J Magn Reson Imaging. 2023 Dec;58(6):1875-1881. doi: 10.1002/jmri.28734. Epub 2023 Apr 13.
Papilledema is thought to be the hallmark sign of increased intracranial pressure (ICP). Distension of the subarachnoid space within the optic nerve sheath is also commonly reported in MR studies as an indirect sign of increased ICP.
General anesthesia and positive pressure ventilation might result in changes in optic sheath diameter (OSD) observed on clinical brain MRI.
Retrospective.
One hundred forty-five patients (154 MRI scans, 7.3 years ± 5.1); 97 studies in the anesthesia group (4.4 years ± 3.4) of which 22 had papilledema, and 57 in the non-anesthesia group (12.3 years ± 3.2), of which 28 had papilledema.
FIELD STRENGTH/SEQUENCE: 1.5T or 3.0T volumetric T2 images. T2 images were obtained from different vendors.
OSD, optic nerve diameter (OND), and peri-optic cerebrospinal fluid (CSF) were measured manually on T2-weighted MR images for various population subgroups (with and without anesthesia; with or without papilledema). The correlation between these measurements and the clinical diagnosis of papilledema was evaluated via receiver operating characteristic (ROC) analysis.
Chi-square test; Mann-Whitney Test; Spearman's test and ROCs; Interclass correlation coefficient, P = 0.05.
General anesthesia resulted in significantly larger mean OSD in patients with or without papilledema (7.3 ± 1.0 mm vs. 6.1 ± 1.1 mm and 6.7 ± 1.0 mm vs. 5.4 ± 0.9 mm, respectively). In the non-anesthesia group, the average OSD values (6.1 ± 1.1 mm) were significantly higher in papilledema patients compared to non-papilledema patients (5.4 ± 0.9 mm), with larger peri-optic CSF rim (1.6 ± 0.4 mm vs. 1.3 ± 0.3 mm). In the anesthesia group, OND was significantly larger in papilledema patients (3.4 ± 0.4 mm vs. 3.1 ± 0.5 mm), though the average peri-optic CSF rim did not reach a significance in papilledema compared with non-papilledema patients (2.0 ± 0.3 mm vs. 1.8 ± 0.4 mm, P = 0.06). In patients with general anesthesia, peri-optic CSF rim had a limited correlation with increased ICP.
In the pediatric population, imaging findings of increased OSD on brain MRI might be related to general anesthesia rather than increased ICP. The interpretation of optic nerve sheath distention should be reported cautiously in conjunction with anesthesia status, especially in the pediatric population.
4 Technical Efficacy: 5.
视乳头水肿被认为是颅内压（ICP）升高的标志性特征。蛛网膜下腔在视神经鞘内的扩张在磁共振研究中也常被报道为 ICP 升高的间接征象。
全身麻醉和正压通气可能导致临床脑 MRI 上观察到的视神经鞘直径（OSD）发生变化。
回顾性。
145 例患者（154 次 MRI 扫描，7.3±5.1 岁）；麻醉组 97 项研究（4.4±3.4 年）中有 22 项有视乳头水肿，非麻醉组 57 项（12.3±3.2 年）中有 28 项有视乳头水肿。
磁场强度/序列：1.5T 或 3.0T 容积 T2 图像。T2 图像来自不同的供应商。
手动在 T2 加权 MR 图像上测量 OSD、视神经直径（OND）和视周脑脊髓液（CSF），用于各种人群亚组（有和无麻醉；有和无视乳头水肿）。通过受试者工作特征（ROC）分析评估这些测量值与视乳头水肿临床诊断之间的相关性。
卡方检验；曼-惠特尼检验；斯皮尔曼检验和 ROC；组内相关系数，P=0.05。
全身麻醉导致有或无视乳头水肿的患者的平均 OSD 显著增大（7.3±1.0mm 与 6.1±1.1mm 和 6.7±1.0mm 与 5.4±0.9mm，分别）。在非麻醉组中，视乳头水肿患者的平均 OSD 值（6.1±1.1mm）明显高于非视乳头水肿患者（5.4±0.9mm），视周 CSF 边缘更大（1.6±0.4mm 与 1.3±0.3mm）。在麻醉组中，视乳头水肿患者的 OND 明显更大（3.4±0.4mm 与 3.1±0.5mm），尽管与非视乳头水肿患者相比，视周 CSF 边缘在视乳头水肿中未达到显著水平（2.0±0.3mm 与 1.8±0.4mm，P=0.06）。在接受全身麻醉的患者中，视周 CSF 边缘与 ICP 升高的相关性有限。
在儿科人群中，脑 MRI 上 OSD 增大的影像学表现可能与全身麻醉有关，而不是与 ICP 升高有关。在解释视神经鞘扩张时，应谨慎报告麻醉状态，尤其是在儿科人群中。
4 级 技术功效：5 级。
