Prognostic Value of Retinal Nerve Fiber Layer and Ganglion Cell Complex after Optic Chiasmal Decompression

Abstract

This paper is an attempt to ascertain the role of the optical coherence tomography by measuring the retinal nerve fiber layer thickness and ganglion cell complex area to predict postoperative visual outcome after chiasmal decompression. 16 eyes scheduled for chiasmal decompression surgery were assessed before and 3 months after surgery with standard automated perimetry and OCT (optical coherence tomography). Preoperative RNFL (retinal nerve fibre layer) thickness and GCC (ganglion cell complex) area were compared with 20 normal control eyes. 13 cases were operated by microscopic assisted endoscopic endonasal transsphenoidal approach; the remaining 3 cases were operated transcranially. Spearman's correlation analysis was used to evaluate the relationship between preoperative RNFL thickness, GCC area, postoperative mean deviation and temporal visual field sensitivity (1/Lambert). Preoperative measurements of RNFL thickness and all GCC area were significantly reduced in the patients compared with normal control. 3 months postoperative evaluation showed improvement of the visual field, but reduction in global and sectorial RNFL thickness except for nasal sector. Moreover, absolute postoperative (not pre-post change) visual field parameters were significantly correlated to preoperative RNFL (P = 0.00399 for mean deviation, P = 0.0023 for temporal sensitivity), GCC thickness (P = 0.00736 for mean deviation, P = 0.0469 for temporal sensitivity), with FLV (focal loss value) (P = 0.0012 for mean deviation, P = 0.0021 for temporal sensitivity) showed a higher correlation. Reduced RNFL thickness mainly, and GCC area minimally, were associated with the worst visual field outcome. FLV is a new prognostic value.

Bi-nasal sectors of ganglion cells complex and visual evoked potential amplitudes as biomarkers in pituitary macroadenoma management

“…Retinal cells are closely interacting with each other and the death of a single cell releases glutamate which triggers an excitotoxic cascade, resulting in nitric oxide production and other metabolite deregulation affecting the survival of surrounding cells ( Pietrucha-Dutczak et al, 2018 ). In the present study, global GCC thickness decreased over time; such reduction was less significant than RFNL thinning, which is in accordance with Salah’s study ( Salah and Ali, 2018 ). VEP amplitude increasing after decompression due to axonal traffic unblocking was more significant than structural variation, so electrophysiology sensed vision recovery better than OCT.…”

“…Tieger et al described persistent damage in the nasal sector at 1-year follow-up in eight patients that attended surveillance visits ( Tieger et al, 2017 ). Other authors also reported the thinning of RFNL and global GCC ( Moon et al, 2011 ; Salah and Ali, 2018 ; Poczos et al, 2022 ). Our results presented in Table 3 data are consistent with the abovementioned findings, and global RNFL and, in less degree, GCC still decrease after surgery (p < 0.05).…”

“…Several authors have suggested that an RNFL thinning could be an indicator of optic nerve atrophy secondary to compression, but it does not imply that ganglion cells were lost ( Moon et al, 2011 ; Danesh-Meyer et al, 2015 ; Salah and Ali, 2018 ). Retinal ganglion cell death occurs after axonal injury and seems to depend on the initiation of apoptosis due to the failure of neuroprotective mechanisms ( Levin, 1999 ; Horton, 2017 ).…”

“…Tieger et al described persistent damage in the nasal sector at 1-year follow-up in eight patients that attended surveillance visits (Tieger et al, 2017). Other authors also reported the thinning of RFNL and global GCC 10.3389/fnint.2022.1034705 (Moon et al, 2011;Salah and Ali, 2018;Poczos et al, 2022).…”

“…Then, after decompression, nerve transmission can be restored in those axons that survived the sustained injury but still a subset of ganglion cells will go into apoptosis (Horton, 2017;Pietrucha-Dutczak et al, 2018). Several authors have suggested that an RNFL thinning could be an indicator of optic nerve atrophy secondary to compression, but it does not imply that ganglion cells were lost (Moon et al, 2011;Danesh-Meyer et al, 2015;Salah and Ali, 2018). Retinal ganglion cell death occurs after axonal injury and seems to depend on the initiation of apoptosis due to the failure of neuroprotective mechanisms (Levin, 1999;Horton, 2017).…”