Neurological outcomes and survival in patients with intracranial lesions undergoing awake craniotomy: a descriptive retrospective single-center study

Abstract

To descriptively evaluate short-term (48–72 h postoperatively) neurological functional outcomes in patients undergoing awake craniotomy for intracranial lesions located within eloquent brain areas, and conduct univariate exploratory analyses of clinical factors correlated with acute postoperative neurological deterioration. Secondary exploratory survival analyses are included solely for hypothesis generation; all survival-related findings carry no definitive clinical prognostic interpretation given the study’s critical limitations of small sample size, pathological heterogeneity, absent long-term functional follow-up, and missing key perioperative covariates. A single-center descriptive retrospective analysis was performed on 30 patients who received awake craniotomy between January 2019 and November 2024. The primary predefined endpoint was new or exacerbated neurological deficits within 48–72 h after surgery, quantified via Karnofsky Performance Status (KPS), Glasgow Coma Scale (GCS), Mini-Mental State Examination (MMSE), and manual muscle strength testing. Early postoperative dysfunction was categorized into three distinct phenotypes: transient global systemic functional decline, focal motor neurological deficits, and isolated language impairment (aphasia). Secondary exploratory endpoints included overall survival and all-cause mortality, with follow-up completed by February 28, 2025. Univariate logistic regression screened correlates of acute neurological decline; Kaplan–Meier survival curves, log-rank subgroup comparisons, and Cox proportional hazards regression were applied for exploratory survival modeling. All survival analyses are interpreted as purely descriptive and hypothesis-generating, with no confirmatory clinical value; the specific constraints are addressed in the Limitations section. The cohort contained 30 patients, with an awake craniotomy intraoperative mapping completion rate of 90.0% (27/30). Within 48–72 h postoperatively, 30.0% (9/30) of patients developed new or aggravated acute neurological dysfunction. Most acute impairments reflected transient global functional decline, including KPS reduction (30.0%) and MMSE cognitive decline (26.7%), while permanent focal injury surrogates (new motor weakness 16.7%; new-onset aphasia 10.0%) were far less frequent. We emphasize that early KPS/MMSE reductions largely stem from temporary perioperative cerebral edema, postoperative fatigue, and residual sedation recovery rather than irreversible focal brain injury. Patients with successful intraoperative awake mapping exhibited a numerically lower rate of acute neurological decline (25.9%) versus patients with mapping failure (66.7%), though this trend did not reach statistical significance (P = 0.20). Univariate logistic regression identified no statistically significant independent predictors of acute postoperative neurological deficits. Median overall survival for the entire cohort was 43.0 months; all subgroup survival comparisons and Cox regression hazard models yielded non-significant results, with no reliable prognostic factors identified in this limited cohort. Awake craniotomy combined with direct electrical stimulation mapping is technically feasible and effectively limits permanent language dysfunction in patients with eloquent cortex lesions. Transient short-term global functional deterioration is common in the immediate postoperative window, driven by reversible perioperative physiological disturbances rather than definitive surgical neurological injury. Owing to the retrospective single-center design, small sample size, heterogeneous intracranial pathology, absence of long-term (≥ 3-month) functional outcome assessments, lack of a general anesthesia control group, and unmeasured critical covariates (including extent of resection), all survival and mortality-related analyses are strictly exploratory and cannot support clinical prognostic judgements. Large, pathology-stratified controlled prospective studies incorporating serial long-term neurological evaluations are required to validate definitive risk factors and long-term functional benefits of awake craniotomy.