Relationship Among Preoperative and Intraoperative Contralateral Analysis along the Perivascular Space Indexes and...

Analysis along the Perivascular Space (ALPS) index has been proposed as a quantitative magnetic resonance imaging (MRI) marker for evaluating the function of the brain's glia-dependent waste clearance pathway, known as the glymphatic system. We hypothesized that the ALPS index on the contralateral side of the brain lesion may relate to postoperative memory disturbance. This study aimed to evaluate the relationship among the preoperative and intraoperative contralateral ALPS indexes and postoperative mini-mental state examination (MMSE) scores in patients with newly diagnosed glioblastoma (GBM).

Thirty-three patients with newly diagnosed, solitary GBMs who underwent intraoperative MRI and diffusion tensor imaging (DTI) were enrolled in this retrospective study. Patient data included tumor volume, peritumoral edema volume, preoperative and postoperative MMSE scores, and the preoperative and intraoperative contralateral ALPS index.

A higher preoperative ALPS index was associated with older age, and a significant negative correlation was observed between the preoperative ALPS index and MMSE scores both before and after surgery, while the index was unrelated to the degree of improvement in the MMSE scores. Unexpectedly, the intraoperative ALPS index tended to show a negative correlation with the postoperative MMSE score and showed a strong correlation with the degree of improvement in the MMSE scores.

These findings suggest that the contralateral glymphatic pathway may associated with irreversible higher brain dysfunction in GBM patients. However, further studies are needed to confirm this speculation.