Glioma surgery in eloquent areas: can we preserve cognition?

Abstract

BackgroundCognitive preservation is crucial in glioma surgery, as it is an important aspect of daily life functioning. Several studies claimed that surgery in eloquent areas is possible without causing severe cognitive damage. However, this conclusion was relatively ungrounded due to the lack of extensive neuropsychological testing in homogenous patient groups. In this study, we aimed to elucidate the short-term and long-term effects of glioma surgery on cognition by identifying all studies who conducted neuropsychological tests preoperatively and postoperatively in glioma patients.MethodsWe systematically searched the electronical databases Embase, Medline OvidSP, Web of Science, PsychINFO OvidSP, PubMed, Cochrane, Google Scholar, Scirius and Proquest aimed at cognitive performance in glioma patients preoperatively and postoperatively.ResultsWe included 17 studies with tests assessing the cognitive domains: language, memory, attention, executive functions and/or visuospatial abilities. Language was the domain most frequently examined. Immediately postoperatively, all studies except one, found deterioration in one or more cognitive domains. In the longer term (3–6/6–12 months postoperatively), the following tests showed both recovery and deterioration compared with the preoperative level: naming and verbal fluency (language), verbal word learning (memory) and Trailmaking B (executive functions).ConclusionsCognitive recovery to the preoperative level after surgery is possible to a certain extent; however, the results are too arbitrary to draw definite conclusions and not all studies investigated all cognitive domains. More studies with longer postoperative follow-up with tests for cognitive change are necessary for a better understanding of the conclusive effects of glioma surgery on cognition.

Recovering and Worsening at Design Fluency in 22 Neurosurgical Patients: Preimmediately Post-surgery and Follow-up Testing

“…This is consistent with previous studies showing a frequent deterioration in one or more cognitive domains in patients with glioma. For a meta-analysis of studies comparing neuropsychological test scores pre-and postsurgery [7]. This is also in line with previous studies showing a deficit in design fluency after surgery [5,6,20]).…”

“…In a recent meta-analysis [7] the need of more studies with longer post-op cognitive follow-up testing to better understand the conclusive effects of glioma surgery on cognition has been highlighted. This is the first preliminary report on data collected pre-and postsurgery and at follow-up in the same patient sample, indicating that an impaired ability in generating novel responses can be subjected to an effect of re-organization/adaptation.…”

“…As fluency refers to the ability to use one or more strategies to achieve the maximum number of new responses and avoiding repetitions [4], it is reasonable to assume that the use of strategies in design fluency tasks can be characterized by flexibility. In a recent meta-analysis [7] the need of more studies with longer post-op cognitive follow-up testing to better understand the conclusive effects of glioma surgery on cognition has been highlighted.…”

“…Similarly, Correa et al [9] studied twenty-five low-grade glioma patients pre-surgery and at 6 and 12 months and found a mild decline 12-month after surgery, and a mild improvement slightly at an additional follow-up (before the 18 th month). In their meta-analysis of studies on glioma patients undergoing neuropsychological tests preand post-surgery, Satoer et al [7] found a highly frequent deterioration in one or more cognitive domains in the immediate post-surgery period, whereas at 3-6/6-12 months postoperatively some patients recovered at some tasks, i.e., language and executive functions.…”

Language neuroplasticity in brain tumour patients revealed by magnetoencephalography

“…There is limited information on language impairment in brain tumour patients and on the relationship between impairment and lesion location (Satoer, Visch-Brink, Dirven, & Vincent, 2016). The present study examines pre-surgical brain tumour patients performing an attentional demanding picture-naming task while their brain activity was monitored with magnetoencephalography (MEG).…”