The Case Series of Contralateral Interhemispheric Transfalcine Approach to Medial Parietooccipital Pathologies: Surgical Technique and Results

Operative Neurosurgery 29:495–504, 2025

This retrospective case series evaluates the contralateral interhemispheric transfalcine approach (PITTA) for medial parietooccipital and peritrigonal brain lesions. The technique offers improved visualization and minimized brain manipulation, with acceptable complication rates, but requires careful venous management and is best suited for experienced neurosurgeons.

The contralateral interhemispheric transfalcine (PITTA) approach is used for challenging medial parietooccipital and peritrigonal brain lesions.

• A retrospective study of 19 cases showed PITTA was applied to vascular lesions (AVMs) and tumors (glioblastomas, meningiomas, metastases, pilocytic astrocytoma).

• The approach improves visualization and reduces manipulation of eloquent cortex and white matter compared to traditional ipsilateral approaches.

• Mean surgery time was about 4 hours 15 minutes, and most patients had temporary neurological deficits that resolved within days.

• Superior sagittal sinus injury and small vein sacrifice occurred in a few cases but were managed without lasting complications.

• No new visual deficits or permanent ipsilateral parietal lobe injuries were observed; most complications were minor and transient.

• PITTA is technically demanding and best suited for experienced neurosurgeons; careful preoperative planning and venous anatomy assessment are critical.

• The study concludes PITTA is a valuable option for selected cases, but larger prospective studies are needed to compare it with standard approaches.

Development and internal validation of a risk score for subsidence of expandable spacers in transforaminal lumbar interbody fusion (TLIF) surgery

Brain and Spine 5 (2025) 104322

This study developed and internally validated the Expandable TLIF Subsidence Index (ETSI) to predict risk of cage subsidence after TLIF surgery with expandable spacers. Key risk factors include high ASA score, non-degenerative indication, lower lumbar levels, small cage size, and posterior cage position.

• A risk score (Expandable TLIF Subsidence Index, ETSI) was developed to predict cage subsidence (CS) after transforaminal lumbar interbody fusion (TLIF) using expandable spacers.

• The study analyzed 388 patients (482 levels), finding a 31.7% CS rate at 3 months.

• Independent risk factors for CS included high ASA score, non-degenerative surgical indication, lower lumbar level, small cage size, and posterior cage position.

• The ETSI score ranges from -2 to 6; higher scores indicate higher CS risk (each point increases CS odds by about 2x).

• Modifiable risk factors (cage size and position) can reduce CS risk if addressed during surgery.

• Higher ETSI scores are also associated with increased risk of non-union/pseudarthrosis.

• The ETSI demonstrated moderate predictive performance (AUROC ≈ 0.68).

• The score may aid surgical planning and should be externally validated in future studies.

Cervical deformity correction: comparison of neurological, radiographic, and patient-reported outcome measures by three-column osteotomy level

J Neurosurg Spine 43:433–442, 2025

Three-column osteotomy (3CO) for cervical deformity at C7–T1 is linked to higher neurological deficits, less radiographic correction, and worse Neck Disability Index outcomes compared to T2–6 levels. Surgeons should prefer 3CO below T1 when feasible for better neurological and functional results.

• Study compared outcomes of three-column osteotomy (3CO) for cervical deformity at C7–T1 vs T2–6 levels.

• Patients with 3CO at C7–T1 had higher rates of new postoperative neurological deficits (56% vs 18%).

• T2–6 3CO resulted in greater radiographic correction (T1 slope and C2–T4 SVA) than C7–T1 3CO.

• Neck Disability Index (NDI) improved after T2–6 3CO but worsened after C7–T1 3CO at 1 year.

• All patients with neurological deficits had at least partial recovery; 20% achieved complete recovery.

• 3CO level selection is multifactorial, but caudal to T1 is recommended when feasible due to better outcomes.

• Study limitations include retrospective design and single-institution data.

• Largest study to date comparing neurological, radiographic, and patient-reported outcomes by 3CO level.

Factors associated with poor prognosis in elderly biopsy‑only glioblastoma patients

Acta Neurochirurgica (2025) 167:273

In elderly glioblastoma patients undergoing biopsy only, poor preoperative performance status, central tumor location, and larger tumor volume were associated with reduced three-month survival and lower treatment completion rates, highlighting the need for careful preoperative assessment and personalized counseling in this vulnerable group.

Study investigated elderly patients (>65 years) with glioblastoma (GBM) who underwent biopsy only, not surgical resection.

• Median overall survival (OS) was 4.6 months; only half completed oncological treatment.

• Poor preoperative performance status (PS), central tumor location, and larger tumor volume were independently associated with reduced three-month survival.

• Poor PS was the only independent predictor for not completing oncological treatment; these patients had very poor survival (median OS 1.6 months).

• Completion of treatment was linked to longer survival (median OS 8.3 months for completers vs. 3.5 months for non-completers).

• Findings suggest limited benefit of biopsy and oncological treatment in elderly GBM patients with poor PS.

• Results can help guide preoperative counseling and decision-making for this vulnerable patient group.

Risk Factors of 90-Day Unplanned Readmission After Lumbar Spine Surgery for Degenerative Lumbar Disk Disease: A Systematic Review and Meta-Analysis

Neurosurgery 97:908–916, 2025

This meta-analysis identified a 7.72% 90-day unplanned readmission rate after lumbar spine surgery. Significant risk factors include older age, higher BMI, depression, diabetes, hypertension, renal failure, and ASA grade >2. Enhanced preoperative optimization and targeted strategies for high-risk patients are recommended to reduce readmissions.

• A meta-analysis of 11 studies (648,415 patients) found a 7.72% incidence of unplanned 90-day readmission after lumbar spine surgery.

• Significant risk factors for readmission include older age, higher body mass index (BMI), depression, diabetes mellitus (DM), hypertension (HTN), renal failure, and an American Society of Anesthesiologists (ASA) grade greater than 2.

• Surgical factors such as fusion and laminectomy were not significantly associated with readmission.

• Main causes for readmission included wound infection, wound dehiscence, and implant failure; disk reherniation was the leading cause at 90 days.

• Enhanced preoperative optimization and careful patient selection are recommended, especially for elderly and high-comorbidity patients.

• Targeted preventive strategies may reduce readmissions and improve healthcare resource utilization.

• Limitations include retrospective study designs and insufficient data on some perioperative risk factors.

Evaluation of Discrepancy Between Radiographic Success and Patient Satisfaction in Adult Spinal Deformity Surgery

Neurosurgery 97:821–828, 2025

Despite radiographic success in adult spinal deformity surgery, 24.1% of patients remained dissatisfied, mainly due to postoperative lumbar stiffness-related disability. Satisfaction was not linked to radiographic parameters but was independently predicted by the modified lumbar stiffness disability index, highlighting the importance of counseling patients about this trade-off.

• About 24.1% of patients were dissatisfied with adult spinal deformity (ASD) surgery despite radiographic success.

• Radiographic success was defined as optimal alignment, no mechanical complications, and no revision surgery.

• Patient satisfaction was measured using SRS-22; scores <4.0 indicated less satisfaction.

• Clinical outcomes (pain, disability, quality of life) improved after surgery, but lumbar stiffness (M-LSDI) worsened.

• No significant differences in radiographic parameters were found between satisfied and less satisfied groups.

• High postoperative lumbar stiffness (M-LSDI score) was the single independent risk factor for dissatisfaction.

• Longer fusion length was associated with higher lumbar stiffness and lower satisfaction.

• Patients should be informed about the trade-off between pain relief and increased lumbar stiffness before surgery.

Novel Delivery System Significantly Improves Technical Success and Safety of the Endovascular Clip System (eCLIPs) While Maintaining Efficacy for the Treatment of Wide-Necked Bifurcation Aneurysms

Neurosurgery 97:963–970, 2025

A prospective registry study found that the new eCLIPs electrolytic bifurcation system (eB) for wide-necked bifurcation aneurysms significantly improved technical success and safety over the prior generation, while maintaining high efficacy, with 96% satisfactory occlusion and low rates of neurological complications and retreatment.

• The eCLIPs device is an endovascular implant designed to treat wide-necked bifurcation aneurysms (WNBAs).

• This study compares two generations: the first-generation eCLIPs bifurcation remodeling system (eBRS) and the newer eCLIPs electrolytic bifurcation system (eB).

• A prospective registry included 280 patients; the eB system showed higher implantation success (92% vs 81% for eBRS, P = .007).

• Both systems achieved high rates of satisfactory aneurysm occlusion (mRROC 1+2: 96%).

• The eB system had lower all-cause (1.1%) and neurological (0.5%) death rates compared to eBRS (7% and 5%, respectively).

• Stroke and repeat procedure rates were low for both devices, with eB performing better (stroke: ~1.7%, repeat procedure: 2.2% vs 8.9% for eBRS).

• eCLIPs compares favorably in safety and efficacy to other devices like WEB and stent-assisted coiling.

• The eB system offers improved procedural success and safety, making eCLIPs a strong option for WNBAs; further studies are recommended.

Volume of parasagittal dura is associated with blood markers of systemic inflammation

Acta Neurochirurgica (2025) 167:255

Higher blood C-reactive protein (CRP), a marker of systemic inflammation, is significantly correlated with lower volume of the parasagittal dura (PSD). This suggests PSD volume may serve as a potential imaging marker of systemic inflammation. No significant association was found between PSD volume and subjective sleep quality.

• The study investigated the relationship between the volume of the parasagittal dura (PSD) and blood markers of systemic inflammation, mainly C-reactive protein (CRP).

• 76 patients underwent intrathecal contrast-enhanced MRI to measure PSD volume and CSF clearance, alongside blood tests for inflammatory markers.

• Higher CRP levels were significantly correlated with lower PSD volume, suggesting an association between systemic inflammation and PSD morphology.

• This inverse relationship was significant even after adjusting for confounders such as age, sex, and diagnosis.

• Other blood markers (hemoglobin, erythrocyte volume fraction) showed initial correlations with PSD volume, but these were not significant after accounting for confounders.

• Impaired sleep quality was associated with higher CRP but not with PSD volume.

• The findings suggest PSD volume may serve as a potential imaging marker of systemic inflammation, but causality remains unclear.

• Further research is needed to clarify mechanisms and clinical implications of the PSD-inflammation link.

Intraoperative vancomycin for preventing infection after open spine surgery: a systematic review and meta-analysis of randomized controlled trials

J Neurosurg Spine 43:509–518, 2025

A meta-analysis of seven randomized controlled trials found that intraoperative vancomycin use in open spine surgery did not significantly reduce rates of superficial or deep surgical site infections. Further large-scale studies are needed to clarify its efficacy and inform clinical guidelines.

• A systematic review and meta-analysis of 7 randomized controlled trials (RCTs) with 2235 patients assessed the efficacy of intraoperative vancomycin in preventing infections after open spine surgery.

• No significant reduction in overall surgical site infections (SSI), deep infections, or superficial infections was found with intraoperative vancomycin compared to control.

• Subgroup analyses showed no benefit in either instrumented or uninstrumented spine surgeries.

• There was no significant shift toward gram-negative or culture-negative infections with vancomycin use.

• Potential risks include local cytotoxicity and possible impairment of bone healing and spinal fusion.

• Current evidence is limited by small sample sizes, heterogeneity in vancomycin administration, and variable follow-up durations.

• The study concludes intraoperative vancomycin may not reduce infection risk and further large RCTs are warranted.

Which interbody device minimized nonunion, subsidence, and reoperation after anterior cervical discectomy and fusion?

J Neurosurg Spine 43:453–463, 2024

This meta-analysis found that allograft spacers in anterior cervical discectomy and fusion (ACDF) result in lower nonunion and revision rates compared to PEEK cages, with no significant difference in subsidence risk. Allograft offers enhanced fusion and minimizes revision without increasing subsidence.

• Allograft and PEEK cages are the most commonly used interbody spacers in anterior cervical discectomy and fusion (ACDF), replacing autograft due to lower donor site morbidity.

• This meta-analysis included 10 studies with 1462 patients comparing allograft and PEEK cages for ACDF, analyzing nonunion, subsidence, and reoperation rates.

• Allograft showed a significantly lower rate of nonunion than PEEK cages (OR 0.33, p = 0.01), indicating better fusion outcomes.

• Reoperation due to nonunion was significantly higher with PEEK cages compared to allograft (OR 0.28, p < 0.01), but overall reoperation rates for any cause were not significantly different.

• No significant difference was found in the incidence or amount of subsidence between allograft and PEEK cages.

• Allograft’s osteoconductive properties likely contribute to its higher fusion rate, while PEEK cages may lead to fibrous interface formation, reducing solid fusion.

• Meta-regression showed no significant effect of smoking, age, or number of fused levels on nonunion rates.

• Conclusion: Allograft is advantageous over PEEK cages in ACDF due to higher fusion rates and lower revision risk, without increasing subsidence

Outcome comparison between interposition and “contactless” transposition microvascular decompression approaches for trigeminal neuralgia

J Neurosurg 143:970–981, 2025

This study compared interposition and “contactless” transposition (Teflon and pericranial sling) microvascular decompression techniques for trigeminal neuralgia. Both were effective, but sling transposition showed improved midterm pain control and fewer complications. The only significant predictor of pain freedom was MRI evidence of clear nerve compression.

• Microvascular decompression (MVD) is a main surgical treatment for trigeminal neuralgia (TN), traditionally using Teflon interposition between nerve and artery.

• Recurrence of TN pain after MVD is often due to Teflon complications, prompting the development of “contactless” transposition techniques such as Teflon and pericranial sling transpositions.

• This retrospective study compared outcomes of interposition, Teflon transposition, and pericranial sling transposition in 305 TN patients.

• Sling transposition was mainly used for severe compression by the superior cerebellar artery and involved securing the artery to the tentorium with a pericranial graft.

• All techniques had similar short-term pain relief and complication rates, but sling transposition showed significantly higher pain-free rates at 2 years compared to other methods.

• Clear vascular compression on MRI was the only significant predictor of pain freedom in multivariate analysis.

• Sling transposition uses autologous tissue, avoids foreign body reactions, and may provide more durable pain control, but is technically more complex.

• Further long-term studies are needed to confirm the durability of sling transposition for TN pain control.

Enhanced Recovery After Surgery Protocol for Microvascular Decompression in Trigeminal Neuralgia: A Retrospective Matched Cohort Study

Neurosurgery 97:936–944, 2025

Implementation of an enhanced recovery after surgery (ERAS) protocol for microvascular decompression in trigeminal neuralgia significantly reduced hospital length of stay, improved postoperative pain scores, and decreased transient hearing alterations compared to conventional care, without increasing complications, according to a retrospective matched cohort study.

• Enhanced Recovery After Surgery (ERAS) protocol was implemented for microvascular decompression (MVD) in trigeminal neuralgia (TN) patients and compared to conventional care in a retrospective matched cohort study.

• ERAS protocol included preoperative counseling, scalp block, small incisions, minimal muscle dissection, total intravenous anesthesia without narcotics, early enteral feeding, and early mobilization.

• 130 patients (65 ERAS, 65 non-ERAS) were analyzed after propensity score matching for key demographics and comorbidities.

• ERAS group had significantly shorter hospital length of stay (1.46 vs 2.95 days, P < .001) and lower postoperative verbal pain scores (1.63 vs 2.48, P = .03) than controls.

• ERAS patients experienced fewer transient postoperative subjective hearing alterations (0 vs 6 cases, P = .03).

• No significant difference in postoperative Barrow Neurological Institute (BNI) pain scores or major complications between groups.

• Subgroup analysis showed ERAS patients discharged at 24 hours had even lower pain scores than controls.

• Study limitations include retrospective design, small sample size, and use of subjective pain scores; larger randomized trials are needed.

Awake surgery with direct electrical stimulation mapping and real‑time cognitive monitoring for functionally guided tumor resection

Acta Neurochirurgica (2025) 167:239

Awake surgery with direct electrical stimulation and real-time cognitive monitoring enables maximal safe brain tumor resection by mapping individual functional networks, preserving quality of life and cognitive abilities. This multidisciplinary, patient-centered approach is gold standard for low-grade gliomas and is increasingly applied to other brain tumors.

• Awake surgery with direct electrical stimulation (DES) mapping is the gold standard for low-grade glioma resection and can also be applied to other brain tumors.

• This approach uses real-time cognitive monitoring to guide tumor removal based on the patient’s individual brain connectome, preserving neurocognitive functions and quality of life.

• A multidisciplinary team—including neurosurgeons, anesthesiologists, and neuropsychologists or speech therapists—is essential for patient selection, preparation, and intraoperative mapping.

• The asleep–awake–asleep protocol with continuous cognitive testing and tailored tasks optimizes functional mapping and minimizes permanent deficits.

• Subpial dissection and limited coagulation reduce vascular injury and promote better cognitive outcomes.

• Early postoperative rehabilitation is crucial for neuroplasticity and functional recovery.

• Careful patient selection and preparation are vital; conditions impairing intraoperative testing are relative contraindications.

• This personalized surgical philosophy has led to high cognitive preservation, low permanent deficit rates, and high return-to-work rates.

Surgical outcomes for spinal arachnoid cysts and webs: a case series

Acta Neurochirurgica (2025) 167:248

This retrospective case series found that surgical treatment for spinal arachnoid cysts (SAC) and webs (SAW) resulted in favorable outcomes (mMC I-II) in 90% and 83% of patients, respectively, with low complication and recurrence rates. Surgery should be considered for symptomatic patients.

• Spinal arachnoid cysts (SAC) and spinal arachnoid webs (SAW) are rare intradural pathologies causing pain and myelopathic symptoms.

• MRI is the main diagnostic tool, but distinguishing between SAC and SAW can be difficult; both may show the “scalpel sign”.

• This retrospective study reviewed 35 patients (29 SAC, 6 SAW) treated surgically from 2011–2023.

• Most patients presented with pain, gait disturbance, sensory, or motor deficits; preoperative neurological status was often not severe.

• Surgical treatment (fenestration or resection) led to favorable outcomes (mMC I-II) in 90% of SAC and 83% of SAW patients.

• Complications occurred in 14.7% of SAC cases but resolved without lasting deficits; no complications in SAW group.

• Recurrence was rare (2.7% in SAC, none in SAW) during short-term follow-up.

• Surgery is recommended for symptomatic patients, with generally favorable short-term results, but larger and longer-term studies are needed.

Microsurgical Resection Versus Stereotactic Radiosurgery for Trigeminal Schwannoma: A Meta-Analysis of 949 Patient Treatment Outcomes

Neurosurgery 97:545–558, 2025

Meta-analysis of 949 trigeminal schwannoma patients found stereotactic radiosurgery (SRS) led to greater improvement in facial hypesthesia and motor deficits, but surgery was superior for facial pain relief. Both approaches provided similar tumor control. Treatment should be individualized based on patient characteristics, tumor profile, and symptoms.

• Trigeminal schwannomas (TS) are rare, benign nerve sheath tumors, with no clear consensus on optimal treatment between surgical resection and stereotactic radiosurgery (SRS).

• Meta-analysis included 29 retrospective studies with 949 patients: 589 had SRS, 360 had surgery; larger tumors were more likely to be treated surgically.

• SRS led to significantly higher rates of facial hypesthesia (numbness) improvement (44% vs 12%) and lower rates of new hypesthesia (4% vs 15%) compared to surgery.

• Surgery was more effective for improving facial pain (81% vs 58% after SRS).

• Both SRS and surgery provided high and similar tumor control rates (89% SRS vs 91% surgery).

• Trigeminal motor function improved more after SRS, but data were limited.

• Treatment choice should be individualized, considering tumor size, patient characteristics, and presenting symptoms.

• Limitations include retrospective design, heterogeneous data, and lack of standardization for outcome measures.

Training on a 3D-Printed Simulation Model Improves Accuracy in External Ventricular Drain Placement

Operative Neurosurgery 29:418–427, 2025

Training neurosurgeons on a 3D-printed simulation model with a standardized protocol significantly improved external ventricular drain (EVD) placement accuracy, reduced variability, and increased confidence, benefitting both junior and experienced practitioners. Regular simulation-based training is recommended to maintain high clinical performance and standardize EVD procedures.

• 3D-printed head models were developed for training neurosurgical residents in external ventricular drain (EVD) placement.

• Training included pre-training, standardized protocol with neuronavigation, and post-training rounds.

• EVD placement accuracy improved significantly after training, with optimal placement rates rising from 55% to 84%.

• Distances to ideal entry and target points, as well as procedure times, were significantly reduced post-training.

• Experience alone did not predict accuracy; even senior neurosurgeons improved, and post-training results were similar across experience levels.

• Right-handed participants achieved better outcomes using their right hand for both sides; left-sided EVDs were more often misplaced.

• Participants’ confidence in EVD placement and direction increased after training.

• Regular, standardized simulation training is recommended for all neurosurgeons, regardless of experience, to maintain high clinical performance.

Surgery for mesial temporal pathology: a 26-year experience

J Neurosurg 143:738–747, 2025

Over 26 years, keyhole craniotomy via the inferior temporal gyrus for mesial temporal lobe surgery showed a low complication rate (5.3%), with only 0.3% permanent neurological deficits. Technique refinement and perioperative strategies minimized risks, supporting this approach as safe and effective for temporal lobe pathology.

A 26-year, single-surgeon study reviewed 717 mesial temporal lobe (MTL) surgeries using a keyhole inferior temporal gyrus (ITG) approach for epilepsy and other pathologies.

• Overall complication rate was low (5.3%), with only 0.3% of patients experiencing permanent neurological deficits and no perioperative deaths.

• Most common complications were hemorrhage (1.5%), postoperative seizure (1.3%), and cosmetic defects (0.6%).

• Neurological complications included transient cranial nerve deficits, visual field deficits, and speech difficulty, all rare.

• No significant correlation found between complications and age, sex, pathology type, operative time, or blood loss.

• Technical strategies such as meticulous closure, careful muscle reapproximation, and limiting brain retraction reduced complications over time.

• The ITG keyhole approach provided safe, effective, and cosmetically favorable access to the MTL, with complication rates improving as technique and teaching matured.

• Long-term follow-up (97% at 36 months) confirmed sustained safety and efficacy of this approach.

Long-term outcomes after microvascular decompression for glossopharyngeal neuralgia

Neurosurg Focus 59(3):E19, 2025

Microvascular decompression (MVD) without neurectomy is effective and safe for glossopharyngeal neuralgia (GPN), with 86% long-term pain freedom and minimal complications. Pain location or radiation did not affect outcomes. Redo MVD is effective for persistent neurovascular compression. High-resolution MRI is useful for preoperative assessment.

• Microvascular decompression (MVD) without neurectomy is effective for glossopharyngeal neuralgia (GPN), including redo procedures.

• In a cohort of 29 patients, 86% were pain free at long-term follow-up (mean 65.3 months); 83% were immediately pain free post-op.

• Complication rates were low: 10% immediate and 11% long-term, with mostly mild symptoms.

• Redo MVD was successful in 3 out of 4 patients with persistent neurovascular compression after prior procedures.

• Pain location or direction of radiation did not affect pain outcomes after MVD.

• Most patients had neurovascular compression (NVC) visible on preoperative MRI, commonly involving the posterior inferior cerebellar artery (PICA).

• MVD is effective even in elderly patients and those with failed prior treatments, provided NVC is present.

• Findings support MVD as a primary treatment for classical GPN, guiding patient selection and management.

The neuronal reserve in glioma surgery: functional reorganization of the motor network examined by navigated transcranial magnetic stimulation and diffusion tensor imaging tractography

J Neurosurg 143:793–804, 2025

This study demonstrates that glioma-induced reorganization of the motor cortex, measured by navigated transcranial magnetic stimulation and diffusion tensor imaging, is linked to functional recovery. Individual neuronal reserve—reflected in motor area resizing, excitability, and tract integrity—may explain differences in disease progression and surgical outcomes.

• Glioma surgery outcomes vary due to individual differences in motor network compensation and adaptation.

• This study used navigated transcranial magnetic stimulation (nTMS) and diffusion tensor imaging (DTI) tractography to measure motor cortex reorganization in glioma patients.

• Motor area relocation, resizing, and changes in excitability were observed in both affected and unaffected hemispheres, indicating bilateral reorganization.

• Greater preoperative motor area size and excitability were associated with better postoperative motor function and recovery.

• Reduced integrity of the corticospinal tract correlated with motor impairment and limited reorganization capacity.

• Functional recovery was linked to increased motor area size, excitability, and area relocation, supporting the concept of an individual neuronal reserve.

• Reorganization patterns were independent of tumor grade, highlighting the importance of personalized risk stratification and treatment planning.

• The study recommends using nTMS data for tailored preoperative risk assessment and patient counseling in glioma surgery.

Dynamic Tumor in Situ Fluid Circulating Tumor DNA Postsurgery Effectively Predicts Recurrence and Clinical Benefits for Glioblastomas

Neurosurgery 97:671–680, 2025

Dynamic monitoring of tumor in situ fluid circulating tumor DNA (TISF-ctDNA) after glioblastoma surgery predicts recurrence earlier than imaging, effectively identifies molecular residual disease, and serves as a robust prognostic biomarker. TISF-ctDNA status guides treatment response assessment and may enable more personalized, timely interventions for GBM patients.

• TISF-ctDNA (tumor in situ fluid circulating tumor DNA) is a promising biomarker for monitoring molecular residual disease (MRD) and recurrence in glioblastoma (GBM) patients after surgery.

• In a prospective study of 37 GBM patients, TISF-ctDNA positivity after surgery was detected in 62.2% of cases and predicted a higher risk of recurrence and shorter progression-free survival (PFS).

• TISF-ctDNA positivity preceded imaging-detected recurrence by a median of 71 days, allowing for earlier intervention.

• Conversion from TISF-ctDNA positive to negative during adjuvant therapy was associated with improved overall survival.

• TISF-ctDNA showed high sensitivity (86.2%) and specificity (100%) in detecting postsurgical MRD recurrence.

• Common tumor gene mutations (EGFR, TP53, PTEN, NF1) did not significantly impact prognosis in this cohort.

• TISF-ctDNA monitoring is less effective for detecting distant tumor recurrences.

• The study supports TISF-ctDNA as an early, noninvasive tool for personalized GBM management, though larger studies are needed for validation.