Limited literature on cognitive outcomes in low-grade glioma (LGG) resection often suggest cognitive decline following surgery. This pilot study implements a brief, targeted neurocognitive evaluation to identify potential cognitive interference which may be secondary to the presence of lesions, as well as monitor cognitive functioning following resection of LGG. This helps to offer specific insight into focal cognitive deficits/changes, as well as potentially aid neurosurgeons in preserving specific cognitive skills.  This provides a paradigm for both positive and negative interference; that is, to either identify any particular deficit that may be secondary to localized lesions, or “clear” a region of any cognitive interference, providing neurosurgeons with data about the potential for any cognitive interruption or potential return following their procedure.

Neurosurgery patients (n=5) undergoing resection of LGGs participated in a brief semi-structured clinical interview designed to solicit any cognitive, motor, or sensory changes/concerns, as well as document affiliated symptoms including syncopal episodes or seizures (with a description of auras, as well as frequency, quality, and duration of events), and psychiatric/emotional changes.  They then participated in a pre-selected brief battery of neuropsychological measures known to evaluate cognitive skill of functional/eloquent areas within and surrounding the region of the identified lesion.  They will also be re- evaluated at one-year post-operatively.

Patients received a standardized mental status exam, as well as measures estimating their premorbid functioning, visuospatial integration/planning, and working memory (i.e., MMSE-2, WTAR, Clock Drawing Test, RCFT-Copy, WAIS-IV Digit Span).  Patients with imaging-confirmed L temporal/temporoparietal lesions participated in HVLT-R, MAE Sentence Repetition, Phonemic and Semantic Fluency.  Patients with imaging-confirmed R temporal/temporoparietal lesions participated in BVMT-R, Benton Visual Form Recognition, and Benton Judgement of Line Orientation (JOLO).  Patients with image-confirmed frontal lesions received the Stroop Test, D-KEFS Design Fluency Subtest, and Trail Making Test (A&B).  Patients with occipital lesions confirmed on imaging will receive the Beery VMI, Benton Visual Form Recognition, and JOLO.

Early results indicate four patients with positively-identified focal cognitive weaknesses (i.e., statistically significant deficits in functioning attributable to eloquent areas adjacent to neuroimaging-confirmed lesions) and one patient negative for cognitive diminution.  Four of the five patients who underwent the protocol have subsequently undergone surgical resection, and three have described subjective cognitive improvement during neurosurgical follow-up.  No patients have yet undergone post-operative neurocognitive evaluation (but assessments are planned).  Neurosurgeons have also reported an enhanced understanding of involved areas secondary to neurocognitive evaluations.

Neuropsychological evaluation is a useful tool in characterization of cognitive functioning for patients with LGG, which is particularly important as deficits may not be observable unless objectively examined. Cooperation with neurosurgical colleagues and appropriate assessment of pre- and post-surgical cognition allows for improved treatment planning, timely intervention, and enhanced patient outcomes.