Retinal Nerve Fiber Layer Thickness Measurement for Predicting Visual Outcome after Transsphenoidal Surgery: Optic Disc Atrophy Is Not the Deciding Indicator

Correlation of pre-operative and post-operative retinal nerve fibre layer thickness with visual outcome following decompression of pituitary macroadenoma

OBJECTIVE

To (i) correlate preoperative retinal nerve fibre layer (RNFL) thickness with visual parameters in patients with pituitary macroadenomas. (ii) study the predictive role of preoperative RNFL in visual outcome following surgery for pituitary macroadenomas (iii) correlate change in postoperative RNFL thickness (RNFLT) with visual outcome.

METHODS

Preoperative and post-operative RNFL thickness of thirty-three consecutive patients operated for pituitary macro adenoma between June 2022 and May 2023 were measured using Optical Coherence Tomography (OCT) and compared with standard visual examination findings and Magnetic Resonance Imaging (MRI) measurements.

RESULTS

A total of 66 eyes of 33 patients who underwent surgical excision of pituitary macro adenoma between June 2022 and May 2023 were studied. The mean age in years of the study group was 44.36 ± 13.77 and both sexes were equally represented (Male: Female = 16:17). RNFL thinning predominantly involved the temporal (51.21+/-15.19 μm) followed by nasal quadrants (62.67+/- 17.03 μm) and correlated well with the visual field (VF) deficit (p <0.001). Patients with severe disc pallor had extremely thin RNFL (less than 67 +/- 8.68 μm). Patients with moderate to severe visual acuity (VA) deficits had significantly thinner RNFLs (65.08±7.09) compared to patients with normal to mild impairment in vision. (83.185±1.2) (p<0.05). RNFL values were significantly thinner for patients with Wilson Grade C, D and E tumours (66.13 ±12.19 μm) compared to those in Grade A and B (77.67±22.12 μm). The mean preop RNFL of patients who showed post-operative improvement in vision was 87.025± 15.02 μm, of patients in whom vision remained static was 74.58 ±18.31 μm. The mean VA (Decimal) increased from a minimum of 0.60 at the pre-operative timepoint to a maximum of 0.68 at the post-operative timepoint. (Wilcoxon Test: V = 42.5, p = <0.001). The mean RNFLT (µm) increased from 77.14 μm at the pre-operative timepoint to 83.77 μm at the post-operative timepoint. (Wilcoxon Test: V = 218.0, p = <0.001). The mean change of RNFL in patients in whom vision improved was 3.6 μm and the mean change of RNFL in patients in whom vision remained static was 9.51 μm. Absence of postoperative visual improvement was noted despite postoperative RNFL thickness improvement in eyes which showed significant preoperative thinning of the nasal (<65 μm) and temporal (<52μm) quadrants.

CONCLUSION

RNFL thinning corelates directly with visual acuity, visual field, and optic disc pallor. Patients with pituitary adenoma have preferential thinning of temporal and nasal quadrants. Visual outcome is better in patients with preserved RNFLT of values more than 82 +/- 5 μm. Reversal of RNFL thinning postoperatively need not necessarily correlate with visual improvement especially in patients who showed significant preoperative thinning of nasal and temporal quadrants.

Optical coherence tomography detects early optic nerve damage before visual field defect in patients with pituitary tumors

Optical coherence tomography (OCT) is a useful tool for predicting visual recovery after the removal of pituitary tumors. However, the utility of OCT in patients with pituitary tumors and a normal visual field is unclear. We aimed to analyze OCT features in pituitary tumors without visual field defects. Pituitary tumors without visual field defects were selected. A total of 138 eyes from 69 patients, assessed by the Humphrey visual field test and OCT, were enrolled in this study. Using preoperative coronal sections of MR images, patients were divided into chiasmal compression (CC) and non-chiasmal compression (non-CC) groups, and OCT characteristics were examined. The CC and non-CC groups consisted of 40 and 29 patients, respectively. There were no differences in age, sex, tumor type, or degree of visual field testing, but the tumor size was different between the two groups. On OCT, macular thickness ganglion cell complex (mGCC) was significantly thinner in the CC group than that in the non-CC group (112.5 vs 117.4 um, P < 0.05). Based on a database of healthy participants, 24% and 2% of eyes in the CC and non-CC groups had abnormal mGCC thickness (P < 0.01), respectively. In a sub-analysis of the CC group, patients with an abnormal mGCC thickness were older than a normal one (58.2 vs 41.1 years, p < 0.01). OCT can detect early optic nerve damage due to optic CC by pituitary tumors, even in normal visual fields. The degree of mGCC thinning may provide an appropriate surgical timing for pituitary tumors that compress the optic chiasm.

Evaluation of preoperative visual pathway impairment in patients with non-functioning pituitary adenoma using diffusion tensor imaging coupled with optical coherence tomography

Objective

Optic chiasma compression and associated visual impairment induced by a non-functioning pituitary adenoma (NFPA) is commonly assessed by the optic disk and retina but is inadequate to understand the entire visual pathway impairment. We aim to evaluate the use of optical coherence tomography (OCT) coupled with diffusion tensor imaging (DTI) for the preoperative evaluation of visual pathway impairment.

Methods

Fifty-three patients with NFPA (categorized into mild and heavy compression subgroups) were subjected to OCT to calculate the thickness of the circumpapillary retinal nerve fiber layer (CP-RNFL), macular ganglion cell complex (GCC), macular ganglion cell layer (GCL), and macular inner plexus layer (IPL), as well as to DTI to calculate the fractional anisotropy (FA) and apparent diffusion coefficient (ADC) values.

Results

Compared to mild compression, heavy compression caused decreased FA value, increased ADC value of several segments of the visual pathway, thin temporal CP-RNFL, and quadrant macular GCC, IPL, and GCL. Average CP-RNFL thickness, inferior-macular inner-ring IPL and GCC thicknesses, inferior CP-RNFL thickness, and superior CP-RNFL thickness were the best indicators of the impairment of the optic nerve, optic chiasma, optic tract, and optic radiation, respectively.

Conclusion

DTI and OCT parameters can effectively evaluate visual pathway impairment and are beneficial for the objective preoperative evaluation of visual pathway impairment in patients with NFPA.

Retinal nerve fiber layer thickness and its correlation with visual symptoms and radiological features in pituitary macroadenoma

Objective

The aim of the study was to evaluate the association of the thickness of retinal nerve fiber layer (RNFL) with (i) visual symptoms and (ii) suprasellar extension defined by magnetic resonance imaging (MRI) in patients with pituitary macroadenoma.

Materials and Methods

RNFL thickness of 50 consecutive patients operated for pituitary macroadenoma between July 2019 and April 2021 were compared with standard visual examination findings and MRI measurements such as optic chiasm height, distance between the optic chiasm and adenoma, suprasellar extension, and chiasmal lift.

Results

The study group included 100 eyes of 50 patients operated for pituitary adenomas with suprasellar extension. RNFL thinning predominantly involved the nasal (84.26 ± 16.43 μm) and temporal quadrants (70.72 ± 14.80 μm) and correlated well with the visual field deficit (P < 0.001). Patients with moderate-to-severe deficit in visual acuity had a mean RNFL thickness <85 μm and patients with severe disc pallor had extremely thin RNFLs (<70 μm). Suprasellar extension defined as Wilsons Grade C, D, and E and Fujimotos Grades 3 and 4 were significantly associated with thin RNFLs <85 μm (P < 0.01). Chiasmal lift more than 1 cm and tumor chiasm distance of <0.5 mm were associated with thin RNFL (P < 0.002).

Conclusion

RNFL thinning correlates directly with the severity of visual deficits in patients with pituitary adenoma. Wilsons Grade D and E, Fujimoto Grade 3 and 4, chiasmal lift more than 1 cm, and chiasm tumor distance <0.5 mm are strong predictors of RNFL thinning and poor vision. Pituitary macro adenoma and other suprasellar tumors need to be excluded in patients with preserved vision but having obvious RNFL thinning.

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.

Predictive Factors of Favorable Visual Outcomes After Surgery of Tuberculum Sellae Meningiomas: A Multicenter Retrospective Cohort Study

BACKGROUND

Because of their proximity to the visual structures, tuberculum sellae meningiomas are frequently revealed by ophthalmologic impairment. The goal of surgery is gross total resection and improvement of visual function. The purpose of the present study was to identify the predictors of favorable visual outcomes after surgery of tuberculum sellae meningioma.

METHODS

We retrospectively collected tuberculum sellae meningiomas treated at 2 neurosurgical centers from 2010 to 2020. We collected the clinical, imaging and surgical data and analyzed their effects on the visual outcome. A favorable visual outcome was defined as an increase in visual acuity of ≥0.2 point and/or an increase of >25% of the visual field or complete recovery.

RESULTS

A total of 50 patients were included. At 4 months after surgery, 30 patients (60%) had experienced visual improvement. The predictors of a favorable visual outcome were a symptom duration of <6 months, preoperative visual acuity >0.5, a smaller tumor size, and tumor with T2-weighted/fluid attenuated inversion recovery hypersignal on magnetic resonance imaging. During surgery, a soft tumor and a clear brain-tumor interface were associated with favorable visual outcomes. Preoperative optic coherence tomography measurements of the retinal nerve fiber layer thickness >80 μM and ganglion cell complex thickness >70 μM were also associated with a better ophthalmologic outcome.

CONCLUSIONS

In tuberculum sellae meningiomas, rapid surgical treatment must be performed to optimize vision improvement. A hyperintense lesion on T2-weighted/fluid attenuated inversion recovery magnetic resonance imaging and minor vision impairment at the initial ophthalmologic presentation might give hope for a favorable outcome. Performing optic coherence tomography measurements before surgery could clarify patients' expectations regarding their recovery.

A pilot study of combined optical coherence tomography and diffusion tensor imaging method for evaluating microstructural change in the visual pathway of pituitary adenoma patients

Background

RNFL thickness measured by optical coherence tomography (OCT) and visual pathway measured by diffusion tensor imaging (DTI) can be used to predict visual field recovery, respectively. However, the relationship between RNFL thickness and visual pathway injury in patients with pituitary adenoma (PA) remains unclear. This study aims to evaluate the combining DTI and OCT methods in observing the microstructural change in the visual pathway in patients with PA.

Methods

Twenty-nine patients who were diagnosed with PA were included in the study group, and 29 healthy subjects were included as the control group. OCT detected the thickness of circumpapillary retinal nerve fiber layer (CP-RNFL) and ganglion cell layer (GCL). DTI measured the values of fractional anisotropy (FA) and apparent diffusion coefficient (ADC). Correlation between CP-RNFL and GCL thickness and FA and ADC values was analyzed in the study group.

Results

Compared with the control group, the FA values of the bilateral optic nerve, chiasma, bilateral optic tract, and left optic radiation in the study group were reduced, and the ADC values of the bilateral optic nerve and optic chiasma were increased. Correlation analysis showed that the FA value of the optic chiasma was positively correlated with the average thickness of RNFL, the CP-RNFL thickness in the nasal and temporal retinal quadrants in both eyes, as well as the thickness of macular ring GCL in the nasal, supra, and inferior quadrants. The FA values of the optic nerve, optic chiasma, optic tract, and optic radiation were positively correlated with CP-RNFL thickness in the nasal and temporal quadrants.

Conclusion

Combined DTI and OCT can provide a comprehensive understanding of the microscopic changes in the structure and function of the whole visual pathway in patients with PA.

Diagnostic and Prognostic Utility of Optical Coherence Tomography in Patients with Sellar/Suprasellar Lesions with Chiasm Impingement: A Systematic Review/ Meta-Analyses

BACKGROUND

In this review, we appraised the current literature on the utility of optical coherence tomography (OCT) as a diagnostic and predictive factor for postoperative visual function outcomes in patients with sellar/suprasellar lesions with chiasmal impingement.

METHODS

A systematic search of PubMed, CINAHL, Scopus, and Cochrane Library was conducted following PRISMA guidelines. Included studies described diagnostic or prognostic utility of OCT in patients with sellar/suprasellar lesions with chiasmal impingement. Meta-analysis was represented with mean difference (MD) with 95% confidence intervals. Meta-regression was performed to determine predictive factors of visual outcomes.

RESULTS

Forty-eight articles were identified for final pooled analysis, representing a total of 2,435 patients with compressive sellar/suprasellar lesions and 952 healthy controls. Mean age was 43.3(11.4) years, with 1,494(48.8%) male and 1,566(51.2%) female patients. Mean retinal nerve fiber layer(RNFL) was significantly different in the study population compared to healthy controls(75.8μ[13.2] vs 91.4μ[10.8], p<0.00001). The nasal segment of RNFL had the largest mean difference (MD -9.76[-12.39, -7.13], p<0.0001). Visual acuity, visual field mean deviation (VF-MD), and visual field pattern standard deviation, all showed significant differences between the study population and healthy controls as well(p<0.0001). Meta-regressions showed significant predictive capability of preoperative RNFL in determining visual function outcome (p<0.05).

CONCLUSION

Our findings provide promising support for the growing evidence that OCT parameters can be utilized as both a diagnostic and prognostic tool for patients with compression of the optic apparatus. There is a need for further studies to gain a better understanding of OCTs and to improve patient outcomes.

Prognostic Utility of Optical Coherence Tomography for Visual Outcome After Extended Endoscopic Endonasal Surgery for Adult Craniopharyngiomas

INTRODUCTION

Owing to the close vicinity of the optic chiasma, visual dysfunction is known as one of the most common surgical indications and postoperative complications in adult patients with craniopharyngiomas, probably leading to poor quality of life. Historically, very few consistent predictive factors associated with the visual outcome are identified, which may not be helpful for patient counseling and preoperative decision making. Recently, optical coherence tomography (OCT) serving as a novel high-resolution imaging technique can assess the retinal morphology by measuring the circumpapillary retinal nerve fiber layer (cpRNFL) and macular ganglion cell complex thickness. However, few studies have examined the prognostic utility of OCT parameters for visual outcome after surgery for craniopharyngiomas. This study aims to use the largest series to evaluate the association between OCT parameters and visual outcome after extended endoscopic endonasal surgery (EEES) for primary craniopharyngiomas in adults.

MATERIAL AND METHODS

From October 2018 to October 2020, one hundred and seventy eyes in 88 adult patients with newly confirmed craniopharyngiomas were retrospectively reviewed and pertinent prognostic factors were analyzed.

RESULTS

Gross total resection was performed in 82 (93.2%) patients. The median postoperative follow-up time was 10.9 months. Multiple logistic regression analysis showed that increased temporal cpRNFL thickness was associated with higher odds of visual acuity (VA) improvement and maintenance (OR = 1.070; 95% CI, 1.005-1.140; p = 0.035), and greater inferior cpRNFL thickness was significantly associated with visual field (VF) improvement and maintenance (OR = 1.034; 95% CI, 1.001-1.068; p = 0.046). Furthermore, tight adhesion between optic nerves and craniopharyngiomas was demonstrated as an independent adverse factor for either postoperative VA or VF (p = 0.048, p = 0.030, respectively). The ROC results further verified the robustness of the prediction model either in VA (AUC = 0.843; 95% CI, 0.734-0.952; p < 0.001) or VF (AUC = 0.849; 95% CI, 0.741-0.958; p < 0.001).

CONCLUSION

Preoperative OCT can effectively predict visual outcome after EEES for adult craniopharyngiomas. It can also serve as a reliable alternative to evaluate preoperative visual field defects, especially for patients with lower compliance. Tight adhesion was confirmed as an independent risk factor for postoperative visual outcome. The OCT-based multivariable prediction models developed in the present study may contribute to patient counseling on visual prognosis.

Ocular manifestations of endocrine disorders

Endocrinopathies are prevalent diseases that typically affect multiple organs, and the eye and orbital tissues are often involved in endocrine disorders. Some conditions, such as diabetes and thyroid gland dysfunction, may cause serious eye pathology and even blindness. A clear insight into the pathogenesis of endocrinopathies and their ocular manifestations would enhance preventive and therapeutic measures and reduce the incidence of sight-threatening complications. This review discusses the ocular manifestations of several endocrine disorders that eye care providers are likely to encounter in clinical practice.

Neuro-ophthalmologic outcomes of standard versus hypo-fractionated stereotactic radiotherapy of AVPM

BACKGROUND

Most anterior visual pathway meningiomas (AVPM) are benign and slow-growing, but these tumors may affect visual functions, including visual acuity (VA) and visual field (VF). Due to location, most are treated non-surgically by fractionated stereotactic radiotherapy (FSRT), aiming to prevent tumor progression and visual functions deterioration. Unfortunately, FSRT in itself may affect visual functions. The current preferred treatment regimen (in terms of safety and effectiveness) is undetermined. While most cases are treated with conventional fractionation (cFSRT)-50.4-54 Gy in 28-30 fractions of 1.8-2 Gy, advances in technology have allowed shortening of total treatment length to hypofractionation (hSRT)-25-27 Gy in 3-5 fractions of 5-9 Gy. Our aim was to evaluate the association of radiotherapy regimen for treating AVPM (cFSRT vs. hSRT) with visual function outcomes (VA, VF) at the last neuro-ophthalmologic evaluation.

METHODS

We conducted a retrospective cohort study of AVPM cases treated at Sheba Medical Center during 2004-2015. We compared cFSRT and hSRT regimens regarding visual function (VA, VF) outcomes at the last neuro-ophthalmologic evaluation. VA was determined by the logarithm of the minimum angle of resolution (LogMAR). VF was determined by the mean deviation (MD). A clinically relevant change in VA was defined as 0.2 LogMAR.

RESULTS

48 patients (13 receiving hSRT, 35 receiving cFSRT) were included, with a median follow-up of 55 months. No significant difference was evident regarding LogMAR or MD of involved eyes at the last evaluation. Six (17%) patients in the cFSRT group experienced clinically relevant VA deterioration in the involved eye, compared with six (46%) in hSRT (p = 0.06).

CONCLUSION

Our findings, using comprehensive and meticulous investigation of visual outcomes, suggest that hSRT may be associated with higher risk for VA and VF deterioration in AVPM especially in ONSM. We recommend the use of cFSRT for ONSM.

The outcomes of conservatively observed asymptomatic nonfunctioning pituitary adenomas with optic nerve compression

OBJECTIVE

The authors investigated the natural history of asymptomatic nonfunctioning pituitary adenomas (NFPAs) with optic nerve compression.

METHODS

This study retrospectively analyzed the natural history of asymptomatic NFPAs with documented optic nerve compression on MRI diagnosed between 2000 and 2016 from 2 institutions. The patients were followed up with regular endocrinological, ophthalmological, and radiological evaluations, and the endpoint was new endocrinopathy or neurological deficits.

RESULTS

The study comprised 81 patients. The median age at diagnosis was 58.0 years and the follow-up duration was 60.0 months. As the denominator of overall pituitary patients, 2604 patients were treated with surgery after diagnosis at the 2 institutions during the same period. The mean initial and last measured values for tumor diameter were 23.7 ± 8.9 mm and 26.2 ± 11.4 mm, respectively (mean ± SD). Tumor growth was observed in 51 (63.0%) patients; however, visual deterioration was observed in 14 (17.3%) patients. Ten (12.3%) patients experienced endocrine deterioration. Fourteen (17.3%) patients underwent surgery for either visual deterioration (in 12 patients) or endocrine dysfunction (in 2 patients). After surgery, all patients experienced improvements in visual or hormonal function. The actuarial rates of treatment-free survival at 2, 3, and 5 years were 96.1%, 93.2%, and 85.6%, respectively. In the multivariate analysis, initial cavernous sinus invasion (HR 4.985, 95% CI 1.597-15.56; p = 0.006) was the only independent risk factor for eventual treatment.

CONCLUSIONS

The neuroendocrinological deteriorations were not frequent and could be recovered by surgery with early detection on regular follow-up in asymptomatic NFPAs with documented optic nerve compression on MRI. Therefore, conservative management could be an acceptable strategy for these tumors. Careful follow-up is required for tumors with cavernous sinus invasion.

Optical Coherent Tomography Predicts Long-Term Visual Outcome of Pituitary Adenoma Surgery: New Perspectives From a 5-Year Follow-up Study

BACKGROUND

Compressive optic neuropathy is the most common indication for transsphenoidal surgery for pituitary adenomas. Optical coherence tomography (OCT) is a useful visual assessment tool for predicting postoperative visual field recovery.

OBJECTIVE

To analyze visual parameters and their association based on long-term follow-up.

METHODS

Only pituitary adenoma patients with abnormal visual field defects were selected. A total of 188 eyes from 113 patients assessed by visual field index (VFI) and 262 eyes from 155 patients assessed by mean deviation (MD) were enrolled in this study. Postoperative VFI, MD, and retinal nerve fiber layer (RNFL) thickness were evaluated and followed up. After classifying the patients into normal (>5%) and thin (<5%) RNFL groups, we investigated whether preoperative RNFL could predict visual field outcomes. We also observed how RNFL changes after surgery on a long-term basis.

RESULTS

Both preoperative VFI and MD had a linear proportional relationship with preoperative RNFL thickness. Sustained improvement of the visual field was observed after surgery in both groups, and the degree of improvement over time in each group was similar. RNFL thickness continued to decrease until 36 mo after surgery (80.2 ± 13.3 μm to 66.6 ± 11.9 μm) while visual field continued to improve (VFI, 61.8 ± 24.5 to 84.3 ± 15.4; MD, -12.9 ± 7.3 dB to -6.3 ± 5.9 dB).

CONCLUSION

Patients with thin preoperative RNFL may experience visual recovery similar to those with normal preoperative RNFL; however, the probability of normalized visual fields was not comparable. RNFL thickness showed a strong correlation with preoperative visual field defect. Long-term follow-up observation revealed a discrepancy between anatomic and functional recovery.

Undetected pituitary adenoma in a patient with retinitis pigmentosa

Background

Retinitis pigmentosa (RP) is one of the most severe hereditary retinal disorders with a worldwide prevalence reaching 1 in every 3000-5000 people and a total of almost one million affected individuals. RP is heterogeneous in its clinical presentations but typically presents as progressive visual dysfunction, including nyctalopia in adolescence, restricted peripheral vision (tunnel vision) in young adults, and loss of central vision at an advanced age.

Case description

Herein, we want to report a case of RP who presented with gradual worsening of vision and headache, and further evaluation revealed a concomitant non-functional pituitary macroadenoma. Ophthalmologic evaluation revealed a little chance for him to regain his vision, so the patient refused to undergo endoscopic surgical resection. However, he is still under clinic-radiologic follow-up, to be evaluated for progression in tumor size and obstructive hydrocephalus.

Conclusion

Presenting with similar symptoms of tunnel vision, the simultaneous occurrence of these two diseases in a patient may delay the diagnosis of the latter, leading to its progression.

Segmented retinal layer analysis of chiasmal compressive optic neuropathy in pituitary adenoma patients

AIMS

To evaluate changes in the segmented retinal layers of pituitary adenoma (PA) patients and to identify the relationship between these changes and visual function.

METHODS

A total of 47 (PA patients) and 22 (healthy subjects) eyes were reviewed from the medical records. The PA patients performed a visual field (VF) test before surgery and 1 month after surgery. By optical coherence tomography scanning, eight retinal layers were measured: retinal nerve fiber layer (RNFL), ganglion cell layer (GCL), inner plexiform layer (IPL), inner nuclear layer (INL), outer plexiform layer, outer nuclear layer, retinal pigment epithelium, and photoreceptor layer.

RESULTS

The PA group showed reduced RNFL, GCL, and IPL thicknesses (p = 0.004,< 0.001,< 0.001) and thicker INL thickness (p = 0.012) than did the controls. The mean deviation of preoperative VF in the PA group was positively correlated with RNFL, GCL, and IPL thicknesses (R = 0.664, 0.720, 0.664; p < 0.001,< 0.001,< 0.001) and negatively correlated with the INL thickness (R = -0.400; p = 0.010). Among the 47 eyes, 32 eyes (68%) were included for subgroup analysis. Preoperative RNFL, GCL, and IPL thicknesses were thicker in the postoperatively improved VF group (p = 0.019, 0.009, 0.005). The preoperative cutoff values for visual recovery were 23.6 μm for RNFL thickness, 30.6 μm for GCL thickness, and 28.9 μm for IPL thickness.

CONCLUSION

During chiasmal compression, the thickening of the INL has presented in addition to thinning of the inner retinal layers. Also, changes in retinal anatomical structures are related to the extent of VF defect and can be used as a predictor of postoperative visual recovery.