Sex Effect on Presurgical Language Mapping in Patients With a Brain Tumor.

Shun Yao,Einat Liebenthal,Adomas Bunevicius,Matthew Vera,Parikshit Juvekar,Alexandra J Golby,Yanmei Tie,Laura Rigolo

doi:10.3389/fnins.2020.00004

Abstract

Differences between males and females in brain development and in the organization and hemispheric lateralization of brain functions have been described, including in language. Sex differences in language organization may have important implications for language mapping performed to assess, and minimize neurosurgical risk to, language function. This study examined the effect of sex on the activation and functional connectivity of the brain, measured with presurgical functional magnetic resonance imaging (fMRI) language mapping in patients with a brain tumor. We carried out a retrospective analysis of data from neurosurgical patients treated at our institution who met the criteria of pathological diagnosis (malignant brain tumor), tumor location (left hemisphere), and fMRI paradigms [sentence completion (SC); antonym generation (AG); and resting-state fMRI (rs-fMRI)]. Forty-seven patients (22 females, mean age = 56.0 years) were included in the study. Across the SC and AG tasks, females relative to males showed greater activation in limited areas, including the left inferior frontal gyrus classically associated with language. In contrast, males relative to females showed greater activation in extended areas beyond the classic language network, including the supplementary motor area (SMA) and precentral gyrus. The rs-fMRI functional connectivity of the left SMA in the females was stronger with inferior temporal pole (TP) areas, and in the males with several midline areas. The findings are overall consistent with theories of greater reliance on specialized language areas in females relative to males, and generalized brain areas in males relative to females, for language function. Importantly, the findings suggest that sex could affect fMRI language mapping. Thus, considering sex as a variable in presurgical language mapping merits further investigation.

Highlights

Image-guided neurosurgery, including presurgical functional mapping with functional magnetic resonance image, is increasingly used by neurosurgeons to perform safer, more precise, and less invasive brain surgery (Golby, 2015)
The aggregate map of brain tumor location in male patients (Figure 1A) shows that the peak tumor locations in males were in the medial aspect of the left middle temporal [9/25 patients; peak coordinate (x, y, z): −34, −15, −10] and inferior frontal (6/25 patients; peak coordinate: −28, 25, 0) cortex, whereas the peak tumor location in females was in the lateral aspect of the left posterior middle temporal gyrus (MTG) (7/22 patients; peak coordinate: −52, −42, 1) (Figure 1B)
The tumor location was included as a covariate in all the functional magnetic resonance imaging (fMRI) analyses, and the interpretation of the fMRI results was constrained in the brain areas differentially affected by tumor in the male and female patients

Summary

Introduction

Image-guided neurosurgery, including presurgical functional mapping with functional magnetic resonance image (fMRI), is increasingly used by neurosurgeons to perform safer, more precise, and less invasive brain surgery (Golby, 2015). Accurate presurgical planning is critical for maximizing tumor removal and maximally preserving eloquent cortices that support critical brain functions, Sex on Presurgical Language Mapping such as motor control and language (Tharin and Golby, 2007; Silva et al, 2018). Presurgical language mapping can facilitate the neurosurgeon’s decision to limit the extent of tumor resection in order to preserve function; or give the neurosurgeon more confidence to proceed with tumor removal, when the tumor is in close proximity to classical language regions. Despite the progress in evaluating language paradigms for fMRI presurgical mapping in brain tumor patients (Tie et al, 2014, 2015; Black et al, 2017), the influence of demographic factors such as sex has not yet been systematically evaluated

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