The Volume of Tumor Mass and Visual Field Defect in Patients with Pituitary Macroadenoma

PURPOSE We used the Swedish interactive threshold algorithms (SITA) standard strategy of Humphrey perimetry, to analyze the pattern of visual field (VF) defects and evaluate the quantitative correlation between the tumor volume and severity of VF defects in patients with pituitary macroadenoma. METHODS We reviewed 50 patients with pituitary macroadenoma who received VF test and 11 patients were excluded. VF analysis was performed with Humphrey perimeter using the SITA standard strategy. The tumor volume was assessed radiologically via brain magnetic resonance images and was calculated using Cavalieri's principle. We used the mean deviation (MD) and pattern standard deviation (PSD) of the Humphrey parameter to measure VF defect severity, and then analyzed the correlation of tumor volume with VF defects. RESULTS Twenty nine patients (74%) showed abnormal VF and bitemporal field changes, which were the most common field defects on presentation. Seven patients (18%) had unilateral VF defects, 22 patients (56%) had bilateral VF defects. The tumor volume of the patients with VF defects was significantly larger than that of patients with normal VF (p = 0.006). The tumor volume exhibited significant negative correlation with MD (r = -0.693; p < 0.001) and significant positive correlation with PSD (r = 0.589; p < 0.001). CONCLUSIONS In patients with pituitary macroadenoma, there was a variety of VF defects and a high correlation between the tumor volume and the severity of VF defects. SITA standard strategy can be a fast and quantitative method for evaluating central VF defects.