Perera Dinan, Rana Khizar, Caltabiano Carmelo, Patel Sandy, Selva Dinesh
Department of Ophthalmology & Visual Sciences, University of Adelaide, North Terrace, Adelaide, SA, 5000, Australia.
South Australian Institute of Ophthalmology, Royal Adelaide Hospital, Port Road, Adelaide, SA, 5000, Australia.
Surg Radiol Anat. 2025 Jan 29;47(1):69. doi: 10.1007/s00276-025-03573-4.
To report the normative dimensions of the frontal nerve (FN) on fat-suppressed suppressed gadolinium (fs-gad) enhanced magnetic resonance imaging (MRI).
A retrospective cohort study of patients who underwent coronal fs-gad T1-weighted MRI. Orbits were excluded if there was unilateral or bilateral pathology of the FN or optic nerve sheath (ONS), incomplete MRI sequences, poor image quality or indiscernible FN on radiological assessment. The maximum diameter of the FN and ONS was measured.
The mean age of participants was 58 ± 16 years and 50% were females (n = 42). The mean normative measurements (mean ± standard deviation) on coronal T1-weighted imaging: optic nerve sheath, 5.08 ± 0.67mm. On coronal fs-gad T1-weighted imaging: frontal nerve, 0.74 ± 0.18mm. No significant differences were found between male or female participants in both the frontal nerve (p = 0.913) or optic nerve sheath (p = 0.646). There was no significant correlation between age and mean diameter of the frontal nerve (r = 0.14, p = 0.067) or optic nerve sheath (r = 0.075, p = 0.336). Additionally, no significant difference was identified between the mean diameter of the frontal nerve (p = 0.075) and optic nerve sheath (p = 0.120) across age groups. The mean frontal nerve to optic nerve sheath ratio was 0.15 ± 0.04.
Normative dimensions of the FN may provide quantitative cut-offs that can aid the diagnosis of FN enlargement seen in instances such as IgG4-related ophthalmic disease (IgG4-ROD) and neoplastic perineural spread.
报告脂肪抑制钆增强磁共振成像（MRI）上额神经（FN）的正常尺寸。
对接受冠状位脂肪抑制钆增强T1加权MRI检查的患者进行回顾性队列研究。如果存在FN或视神经鞘（ONS）的单侧或双侧病变、MRI序列不完整、图像质量差或在影像学评估中FN不可辨认，则排除眼眶。测量FN和ONS的最大直径。
参与者的平均年龄为58±16岁，50%为女性（n = 42）。冠状位T1加权成像的平均正常测量值（平均值±标准差）：视神经鞘，5.08±0.67mm。冠状位脂肪抑制钆增强T1加权成像：额神经，0.74±0.18mm。男性和女性参与者在额神经（p = 0.913）或视神经鞘（p = 0.646）方面均未发现显著差异。年龄与额神经平均直径（r = 0.14，p = 0.067）或视神经鞘（r = 0.075，p = 0.336）之间无显著相关性。此外，各年龄组之间额神经平均直径（p = 0.075）和视神经鞘平均直径（p = 0.120）无显著差异。额神经与视神经鞘的平均比值为0.15±0.04。
FN的正常尺寸可能提供定量界限，有助于诊断IgG4相关眼病（IgG4-ROD）和肿瘤性神经周围扩散等情况下出现的FN增粗。
