Georgetown University School of Medicine, Washington, District of Columbia, USA
University of Arizona College of Medicine Phoenix, Phoenix, Arizona, USA.
Br J Ophthalmol. 2020 Oct;104(10):1458-1461. doi: 10.1136/bjophthalmol-2019-315524. Epub 2020 Feb 5.
In patients with optic nerve hypoplasia (ONH), the visualisation of the optic disc can be challenging and the definitive diagnosis difficult to ascertain without fundus photography. The use of MRI for diagnosis has been reported as a diagnostic alternative with conflicting results. We retrospectively analysed a disease registry to determine the reliability of orbital MRI measurements of the optic nerve diameter to diagnose ONH, and the correlation with vision outcomes.
From a cohort of 140 patients with ONH (13% unilateral) that had reached age 5 years, we identified 43 subjects who had orbital MRI in addition to fundus photography performed prior to 2 years of age. We compared measurements of the optic nerve diameter from orbital MRI scans to the standard relative optic disc size (disc diameter/disc-macula (DD/DM) distance) by fundus photography. All patients had visual acuity tested at age 5 years. Spearman's correlation coefficient was used to determine the correlation of orbital MRI measurements and fundus photography with the diagnosis of ONH, and with vision outcomes.
Relative disc size (DD/DM)<0.35 showed 100% sensitivity and 100% specificity for the diagnostic confirmation of ONH. The optic nerve diameter measurements by orbital MRI displayed a moderate correlation (r=0.471; p<0.001) with DD/DM and moderate sensitivity for the diagnosis of ONH. Final visual acuity correlated well with DD/DM measurements by fundus photography (r=-0.869; p<0.001) and moderately with optic nerve diameter by orbital MRI (r=-0.635; p<0.001).
Orbital optic nerve diameter from MRI scans has moderate reliability in diagnosing ONH and predicting vision outcomes. Fundus photography for measurements of the optic nerve size should remain the reference for diagnostic confirmation of ONH. These data further support the prognostic value of fundus photography for eventual vision outcomes in this population.
在视神经发育不全（ONH）患者中，如果没有眼底照相，视盘的可视化可能具有挑战性，并且难以确定明确的诊断。MRI 用于诊断的报道被认为是一种具有冲突结果的诊断替代方法。我们回顾性地分析了一个疾病登记处，以确定眼眶 MRI 测量视神经直径诊断 ONH 的可靠性，以及与视力结果的相关性。
从一个达到 5 岁的 140 例 ONH（13%单侧）患者队列中，我们确定了 43 例患者在 2 岁之前除了眼底照相外还进行了眼眶 MRI。我们比较了眼眶 MRI 扫描的视神经直径测量值与眼底照相的标准相对视盘大小（视盘直径/视盘黄斑（DD/DM）距离）。所有患者在 5 岁时均接受了视力测试。使用 Spearman 相关系数确定眼眶 MRI 测量值和眼底照相与 ONH 诊断以及与视力结果的相关性。
相对视盘大小（DD/DM）<0.35 对 ONH 的诊断确认具有 100%的敏感性和 100%的特异性。眼眶 MRI 测量的视神经直径与 DD/DM 呈中度相关性（r=0.471；p<0.001），对 ONH 的诊断具有中度敏感性。最终视力与眼底照相的 DD/DM 测量值高度相关（r=-0.869；p<0.001），与眼眶 MRI 的视神经直径中度相关（r=-0.635；p<0.001）。
眼眶 MRI 扫描的视神经直径在诊断 ONH 和预测视力结果方面具有中等可靠性。用于视神经大小测量的眼底照相应仍然是诊断确认 ONH 的参考标准。这些数据进一步支持眼底照相对该人群最终视力结果的预后价值。
