Ting Darren S J, Pradhan Sayali P, Barnes Eric, Ahmed Omar A, Figueiredo Francisco C
Birmingham and Midland Eye Centre, Birmingham, UK.
Academic Unit of Ophthalmology, Institute of Inflammation and Ageing, University of Birmingham, Birmingham, UK.
Am J Ophthalmol Case Rep. 2023 Jan 21;29:101804. doi: 10.1016/j.ajoc.2023.101804. eCollection 2023 Mar.
Neurotrophic keratopathy (NK) is an uncommon but challenging clinical condition characterized by altered corneal nerves and sensation leading to corneal damage. Corneal neurotization, a surgical technique that aims to "re-innervate" the cornea, has gained increasing popularity in view of the potential to permanently improve or even restore the normal corneal sensation. In this study, we aimed to report the outcomes of two cases of NK that underwent indirect minimally invasive corneal neurotization (MICN) with a sural nerve autograft, and to provide plausible explanations for the observed clinical outcomes.
This was an interventional case series of two patients who underwent MICN for severe unilateral NK. The MICN technique was adapted from the technique originally described by Elbaz et al., in 2014. Clinical severity of NK was graded according to Mackie's grading system. Corneal sensation was measured using the Cochet-Bonnet esthesiometer (0-60mm) and corneal nerves were examined using confocal microscopy (IVCM) with Heidelberg HRT3 Rostock Corneal Module. Patient 1 was a 70-year-old man with a right grade III NK following trigeminal nerve decompression for trigeminal neuralgia. Patient 2 was a 62-year-old man with a left grade II NK following a left-sided acoustic neuroma resection. The denervation time was 23 years for both patients. Following the MICN surgery, none of the patients achieved sustained improvement in the corneal sensation (though patient 1 achieved a transient improvement in central corneal sensation to 20mm at 4 months' postoperative before returning to 0mm at 6 months' postoperative). IVCM did not reveal any changes in the corneal nerve density and morphology post-MICN.
Based on our observations and the literature, we postulate that long denervation time, proximal injury to the trigeminal nerve and older patient age may serve as poor prognostic factors for MICN. As CN is being increasingly adopted in clinical practice for treating NK, understanding of these potential factors will facilitate better risk-benefit stratification and patient counselling. Future larger studies are required to elucidate these findings.
神经营养性角膜病变（NK）是一种罕见但具有挑战性的临床病症，其特征是角膜神经和感觉改变，导致角膜损伤。角膜神经化是一种旨在“重新支配”角膜的手术技术，鉴于其有可能永久性改善甚至恢复正常角膜感觉，该技术越来越受欢迎。在本研究中，我们旨在报告两例接受腓肠神经自体移植间接微创角膜神经化（MICN）的NK病例的结果，并对观察到的临床结果提供合理的解释。
这是一个涉及两名因严重单侧NK接受MICN的患者的介入性病例系列。MICN技术改编自Elbaz等人于2014年最初描述的技术。NK的临床严重程度根据Mackie分级系统进行分级。使用Cochet-Bonnet触觉计（0-60mm）测量角膜感觉，并使用带有海德堡HRT3罗斯托克角膜模块的共聚焦显微镜（IVCM）检查角膜神经。患者1是一名70岁男性，因三叉神经痛接受三叉神经减压术后出现右侧III级NK。患者2是一名62岁男性，左侧听神经瘤切除术后出现左侧II级NK。两名患者的去神经时间均为23年。MICN手术后，所有患者的角膜感觉均未实现持续改善（尽管患者1在术后4个月时中央角膜感觉短暂改善至20mm，术后6个月时恢复至0mm）。IVCM未显示MICN术后角膜神经密度和形态有任何变化。
基于我们的观察结果和文献，我们推测去神经时间长、三叉神经近端损伤以及患者年龄较大可能是MICN预后不良的因素。由于CN在临床实践中越来越多地被用于治疗NK，了解这些潜在因素将有助于更好地进行风险效益分层和患者咨询。未来需要更大规模的研究来阐明这些发现。
