Assessment of acalculia in patients with glioma: systematic review of the literature

Background: Acalculia is an acquired disorder of numerical skills whose assessment is not traditionally included in the three-stage protocol specific to awake glioma neurosurgery. Nevertheless, this disorder can significantly impact patient’s daily life. This review aims to describe the importance of assessing numerical and practical skills to optimize quality of life.Method: Ninety-eight articles from three databases were reviewed by at least two authors, selecting 17 for qualitative analysis (n=297 patients). Most scored 75–100% on the CARE grid, with robustness classifying 10 as C, 3 as D, and 4 as B.Results : Among the 297 patients, 239 were preoperatively investigated for a potential acalculia with 8.8% (n=21) showing numerical disorders. Postoperatively, among 132 patients assessed for an acalculia, 14.4% (n=19) had numerical disorders. Of these, 42.1% (n=8) were inaugural cases while 36.8% (n=7) had no specific numerical skills assessment. Lastly, among 162 patients assessed at all three phases, 88.9% (n=144) showed no postoperative numerical disorder. Then, this review highlights disparities in numerical assessment during awake neurosurgery: none of the 17 studies follows the same evaluation protocol, especially for numerical tasks.Conclusion : These findings suggest assessing numerical skills during operative phases specific to awake surgery helps prevent the onset of postoperative acalculia. However, it is regrettable that these data cannot be completed and compared with the percentage of patients who performed some numerical tasks 90.6% (n=269) without being screened for a postoperative acalculia 39.7% (n=107). Finaly, this analysis highlights significant disparities between protocols used to assess numerical skills.