The supraorbital and supratrochlear nerves for ipsilateral corneal neurotization: anatomical study

Abstract

Neurotrophic keratitis is a rare corneal disease that is challenging to treat. Corneal neurotization (CN) is among the developing treatments that uses the supraorbital (SON) or supratrochlear (STN) nerve as a donor. Therefore, the goal of this study was to provide the detailed anatomy of these nerves and clarify their feasibility as donors for ipsilateral CN. Both sides of 10 fresh-frozen cadavers were used in this study, and the SON and STN were dissected using a microscope intra-and extraorbitally. The topographic data between the exit points of these nerves and the medial and lateral angle of the orbit were measured, and nerve rotation of these nerves toward the ipsilateral cornea were attempted. The SON and STN were found on 19 of 20 sides. The vertical and horizontal distances between the exit point of the SON and that of the STN, were 7.3±2.1 mm (vertical) and 4.5±2.3 mm, respectively. The mean linear distances between the medial angle and the exit points of each were 22.2±3.0 mm and 14.5±1.9 mm, respectively, and the mean linear distances between the lateral angle and the exit points of the SON and STN were 34.0±2.7 mm and 36.9±2.5 mm, respectively. These nerves rotated ipsilaterally toward the center of the orbit easily. A better understanding of the anatomy of these nerves can contribute to the development and improvement of ipsilateral CN.

Corneal Neurotization—Indications, Surgical Techniques and Outcomes

“…Despite their differences, both the supraorbital and supratrochlear nerves can be reliably dissected and used for neurotization. An anatomical study on 10 cadavers performed by Kikura et al showed that both nerves have sufficient length for ipsilateral transfer and could be rotated to the center of the orbit without damage induced by excessive tension, supporting their use for neurotization [ 78 ]. Similarly, Leyngold et al showed how a minimally invasive endoscopic technique could be used to perform an ipsilateral supraorbital nerve transfer while avoiding the complications of an open coronal approach [ 41 ].…”

Neurotization of the human cornea – A comprehensive review and an interim report

“…This challenge is addressed with SCN or minimally invasive corneal neurotization (MICN), which utilizes a healthy donor nerve graft to re-innervate the diseased cornea. [ 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 ] Surgical neurotization is an established treatment option for brachial plexus injury. [ 83 ] The idea of SCN was first discussed in 1972 by Samii.…”

Customized Neurotization for Hindlimb Hemiplegia After a Hemorrhagic Stroke

“…Hypertensive intracerebral hemorrhage(HICH) generally contributes to a catastrophic, life-changing damage with an incidence of approximately 150 in 100,000 worldwide annually,wherein >81.3% of these damages includes severe hemiplegia in the contr-alateral limbs [1][2][3][4].The victims with a limb motor dysfunction signi cantly lose self-help ability, placing a burden on family or forfeiting social engagement to some extent [5][6][7][8][9][10]. Traditionally,fundamental interventions to hemiplegia after HICH revolve around subsequent physical rehabilitation or physiotherapy [11][12][13][14].Nevertheless,res-ultant outcomes usually are discouraging or dissatisfactory,rousing uninterrupted quest for patient-oriented therapies.Many studies conducted in both humans and rodents have demonstrated that an injured brain cortex can re-control the contralateral limbs through a neural network remodeling across perilesional regions and contralesional hemisphere after rewiring an afferent circuit [15][16][17][18].Recently,peripheral nerve transfer,which can ignite compensational cerebral plasticity,has been exploited to rescue partial knee extension or hand prehension in patients with acute accid myelitis or central neurological diseases [19][20][21][22].Noticeably,though current neurotization stays in early stage and yet need to be polished [23,24],its highlights have activated our aspiration for its extrapolation to a lower-limb paralysis after HICH,and further interrogation of maneuvers for a dexterous motion during neurotization.…”