Study design and subjects
This case-control study included patients with pituitary adenoma in the Neurosurgery Department of Shanxi Provincial People’s Hospital between October 2019 and June 2021. The inclusion criteria were 1) diagnosed with pituitary adenoma by cranial magnetic resonance imaging (MRI) on hospital admission, underwent transsphenoidal resection of pituitary adenoma, and confirmed as pituitary adenoma by postoperative pathological examination; 2) preoperative cranial MRI showed optic chiasm compression (or not), and cranial MRI in 3 months after the surgery did not show any optic chiasm compression; 3) corrected visual acuity (CVA) ≥0.1, and could cooperate with the VF test; 4) VF test showed typical temporal VF defect accompanied with (or not) nasal VF defect, and 5) age ≤ 70-years-old. The exclusion criteria were 1) patients with recurrent pituitary adenoma; 2) patients with anterior segmen,retinal or optic nerve disease ; 3) VF test results were unreliable (i.e., the rates of false positive, false negative, or fixation loss were >25%); 4) history of glaucoma and IOP >21 mmHg; 5) patients with diabetes, high myopia, or other systemic diseases or condition that influenced the retina or optical nerve; or 6) could not adhere to follow-up. This study followed the Declaration of Helsinki and was approved by the Ethics Committee of Shanxi Provincial People’s Hospital.
Cranial MRI examination was performed before and at 3 months after the surgery to clarify the correlation between pituitary adenoma and optic chiasma. Optic chiasma compression was defined as a visible contact of the highest point of pituitary adenoma to the optic chiasma on at least one image, with optic chiasma up-shifting. MRI images were evaluated tumor size,because the shape of pituitary tumor is irregular,and the vertical diameter has greatest influence on optical chiasma,the latter is used to defined the size of the tumor.Vertical diameter refers to the height from the bottom to the top of the tumor measured on the largest coronal plane of the tumor,the MRI images was performed by a radiologist who was blinded to the patients, data.The bilateral VA and CVA were assessed using a standard VA chart. The VF test was repeated after correction of refractive errors using the Central 24-2 SITA FAST software and a Humphrey Field Analyzer II750 (Carl Zeiss AG, USA). The reliability parameters, including false-positive rate, false-negative rate, and fixation loss rate, were maintained at <20%. The mean deviation (MD) of the VF indices was measured to reflect the degree of VF defect. The OCT examination was performed using three-dimensional (3D) OCT (3D OCT-2000 software version 8.00; Topcon, Tokyo, Japan) at a scanning rate of 50,000 A scans/s. The 3D disc 6×6 mode was used to measure the average and superior, inferior, nasal, and temporal RNFL by scanning the peri-optic disk. The macular mode included a 512 (vertical scan) × 128 (horizontal scan) matrix with the raster scanning of the central fovea s 7 mm2 and the scanning of the central fovea with an area of 6×6 mm. The average value of a 10×10 square was automatically calculated by the software, and the quadrants that centered on the macular central fovea were divided into four sections: nasal superior, nasal inferior, temporal superior, and temporal inferior. All patients were examined by the same investigator. Only well-focused, well-centered images with high signal intensities (≥25) and no artifacts from eye movements were used for analysis. The distance between the external border of RNFL and IPL was defined as the mGCIPL.
The demographic characteristics of the patients, including sex and age,duration of symptom from the first visual symptoms to diagnosis of the tumor,tumor size,tumor type were collected. The optical examination parameters, such as VA, best CVA, IOP, diopter, ocular fundus, VF defect degree, RNFL, and GCIPL, were measured before and 6 months after the surgery. In addition, the data of the optic chiasma before and at 3 months after the surgery were recorded.
Temporal VF defect was defined as complete or partial temporal VF defect. No VF defect was defined as the absence of ≤3 continuous scotomas with the probability <5%, shown by pattern deviation probability plot (PDPP).The recovery of VF defect was defined as mean deviation (MD) ≥ -4dB and the absence of ≤3 continuous scotomas with the probability <5%, shown by pattern deviation probability plot (PDPP).The patients were divided into the VF did not recover group (VFNR), and the VF recovered group (VFR).
SPSS 22.0 (IBM Corp., Armonk, NY, USA) was used for statistical analysis. A normality test was performed for the continuous data. Normally distributed continuous data were presented as means ± standard deviations and compared using the t-test. Continuous data with a skewed distribution were described as median (Q25, Q75) and compared using a non-parametric test. The categorical variables were described as n (%) and analyzed using the chi-square test or Fisher’s exact test. The risk factors for VF defect improvement were assessed by multivariable logistic regression analysis. Receiver operating characteristics (ROC) curve analyses were performed. Two-sided P-values <0.05 indicated statistical significance.