Long term predictive ability of preoperative retinal nerve fiber layer thickness in visual prognosis after chiasmal decompression surgery

Prognostic Value of Optical Coherence Tomography Characteristics in Anterior Visual Pathway Meningiomas

BACKGROUND

Anterior visual pathway meningiomas (AVPM) represent 2.5%-18% of all meningiomas. They may affect visual function, including visual acuity (VA) and visual field (VF). The principal modes of treatment are surgery and radiotherapy. The prognostic value of macular ganglion cell complex count (GCC) thickness has not been assessed in the literature thus far. The purpose of this study was to evaluate the prognostic value of pre-treatment optical coherence tomography (OCT) parameters (retinal nerve fiber layer and GCC) for visual outcomes in patients with AVPM.

METHODS

We retrospectively reviewed the medical records of all patients with AVPM who were treated in the Sheba Medical Center between 2011 and 2020. Included were patients with valid data containing preintervention OCT findings on the CIRRUS device and a minimum follow-up of 6 months. Preintervention and postintervention data on comprehensive ophthalmic examinations and OCT parameters of the affected eyes were retrieved. The correlation between preintervention OCT parameters and the visual outcome was assessed. The patients were also divided into 2 groups according to preintervention GCC (thin vs normal), and the visual outcome was compared between groups.

RESULTS

In total, 186 patients' medical records were analyzed, and 38 patients who met the inclusion criteria were included in the study (mean age at diagnosis 52.8 ± 12.2 years, 28 women). Twenty-nine patients had 1 affected eye, and 9 had bilateral insult. A higher preinterventional average GCC was associated with better VA at 6 months, 1 year, and 2 years after intervention (r = -0.5, P ≤ 0.004, 0.005, and 0.03, respectively). There was a significant correlation between preinterventional GCC and VF mean deviation 2 years after intervention (r = 0.7, P ≤ 0.001). The thinner the GCC, the more prominent was the change in VA from before intervention to 2 years after intervention ( P ≤ 0.008). Correction for multiple comparisons with the Benjamini-Hochberg procedure did not change the significance of our findings.

CONCLUSIONS

OCT parameters (GCC) have a predictive value in AVPM. There is strong correlation between preinterventional GCC and VA shortly after the intervention. Although a thin GCC is generally considered a negative prognostic factor, improvement in clinical parameters was also evident in patients with thin GCC. The potential of improvement despite preinterventional GCC thinning can add to the clinical discussion of the prognosis, and therefore, we recommend the patients with AVPM to undergo OCT and to be advised that GCC thinning alone should not be used as a major criterion in deciding whether treatment should be pursued.

Ocular Optical Coherence Tomography in the Evaluation of Sellar and Parasellar Masses: A Review

Compression of the anterior visual pathways by sellar and parasellar masses can produce irreversible and devastating visual loss. Optical coherence tomography (OCT) is a noninvasive high-resolution ocular imaging modality routinely used in ophthalmology clinics for qualitative and quantitative analysis of optic nerve and retinal structures, including the retinal ganglion cells. By demonstrating structural loss of the retinal ganglion cells whose axons form the optic nerve before decussating in the optic chiasm, OCT imaging of the optic nerve and retina provides an excellent tool for detection and monitoring of compressive optic neuropathies and chiasmopathies due to sellar and parasellar masses. Recent studies have highlighted the role of OCT imaging in the diagnosis, follow-up, and prognostication of the visual outcomes in patients with chiasmal compression. OCT parameters of optic nerve and macular scans such as peripapillary retinal nerve fiber layer thickness and macular ganglion cell thickness are correlated with the degree of visual loss; additionally, OCT can detect clinically significant optic nerve and chiasmal compression before visual field loss is revealed on automated perimetry. Preoperative values of OCT optic nerve and macular parameters represent a prognostic tool for postoperative visual outcome. This review provides a qualitative analysis of the current applications of OCT imaging of the retina and optic nerve in patients with anterior visual pathway compression from sellar and parasellar masses. We also review the role of new technologies such as OCT-angiography, which could improve the prognostic ability of OCT to predict postoperative visual function.