Addressing Temporal Muscle Atrophy and Enhancing Cranioplasty Outcome

Operative Neurosurgery 30:588–594, 2026

This multicenter prospective study evaluates a dual-layer dural substitute technique during decompressive craniectomy to prevent adhesions between the temporalis muscle and dura, thereby improving subsequent cranioplasty outcomes. Across 59 patients, the method reduced adhesions, preserved temporalis muscle thickness, shortened cranioplasty operative time, minimized blood loss, and eliminated postoperative cranioplasty-related seizures.

The paper details surgical steps, material selection (Neuro-Patch), intraoperative placement of two dural layers, and cranioplasty retrieval of the superficial patch to restore muscle function. Results show improved wound healing metrics, shorter hospital stays, and a low complication profile, while noting limitations including lack of a control group and nonstandardized long-term follow-up.

Problem: After decompressive craniectomy (DC), adhesions commonly form between the temporalis muscle (TM), dura, and brain surface, making later cranioplasty (CP) dissection difficult and increasing risks such as TM injury/atrophy and poor cosmetic outcome.

Technique: During DC, place a dual-layer dural substitute—a large patch for duraplasty plus a second patch beneath the TM (and sometimes an additional patch between TM and subcutaneous tissue)—to preserve a separable plane for future CP.

CP approach: During CP, reopen the prior incision and elevate the musculocutaneous flap between the two Neuro-Patch layers, then remove the patch under the TM and reposition the TM anatomically over the implant.

Study design: Three-year prospective multicenter series of 59 patients undergoing DC then CP; outcomes included adhesion formation, ease of dissection, TM thickness (CT-based), operative time, blood loss, and postoperative events.

Adhesion/TM preservation results: TM elevation during CP was consistently facilitated with nearly absent fibrotic adhesion, and TM thickness remained essentially unchanged pre- vs postoperatively (median 5.6 mm vs 5.5 mm).

Operative metrics: Median CP operative time was 66 minutes vs a previously estimated 105 minutes in centers not using the technique; mean blood loss was 24 mL.

Safety/complications: No reported infections, wound dehiscence, or CSF leak after DC and CP; 0% post-CP new-onset seizures in this cohort.

Conclusion: Dual-layer dural substitute placement during DC can prevent adhesions and improve subsequent CP by facilitating TM elevation, reducing operative time and blood loss, preserving TM integrity, and potentially lowering post-CP epilepsy rates.

Percutaneous Trigeminal Ganglion Stimulation as a Treatment Modality for Anesthesia Dolorosa

Neurosurgery Practice 2026;7(1):e000191.

This case report describes successful percutaneous trigeminal ganglion stimulation (TGS) in a 71-year-old woman with anesthesia dolorosa (AD) after multiple rhizotomies for trigeminal neuralgia related to multiple sclerosis. The authors detail implantation technique, trial and permanent lead placement, stimulation parameters, and sustained clinical improvement over three years without major complications.

The article situates TGS within neuromodulation strategies for refractory deafferentation pain, reviews prior peripheral nerve stimulation evidence, and discusses mechanisms, patient selection considerations, and hardware anchoring challenges. The authors conclude TGS is a promising option for refractory AD and call for further research to refine indications and device fixation.

Condition Anesthesia dolorosa (AD) is a rare, debilitating deafferentation pain syndrome (incidence ~0.3%–2%) that often follows iatrogenic trigeminal nerve injury such as trigeminal rhizotomy and is frequently refractory to medications.

Patient case A 71-year-old woman with trigeminal neuralgia secondary to multiple sclerosis developed severe, medically refractory AD after multiple rhizotomies, with burning jaw pain and substantial numbness that impaired eating, talking, and oral hygiene.

Intervention An off-label percutaneous trigeminal ganglion stimulation (TGS) externalized trial was offered because some sensation was preserved.

Procedure Under fluoroscopic guidance, an electrode was advanced via a Jamshidi needle through the foramen ovale to the trigeminal ganglion region and secured on the cheek/postauricular area; an external generator was connected for the trial.

Trial outcome Over ~2 weeks of continuous stimulation, pain during episodes improved from 9/10 to 0–1/10, and relief persisted until permanent implantation 2 months later.

Durability After permanent implantation (St. Jude Octrode lead; generator in left chest wall), the patient reported 0–1/10 burning pain with return to baseline activities, with stable relief for 3 years with minimal setting adjustments alongside baclofen and pregabalin.

Rationale TGS is proposed to help restore tonic signaling to the trigeminal nucleus to rebalance excitatory/inhibitory processing and alleviate pain, potentially even with severe peripheral deafferentation.

Implications/limits This single case supports TGS as a promising option for refractory AD and warrants further investigation; practical challenges include achieving robust facial lead anchoring and defining optimal indications/trial criteria.

Microsurgery Versus Embolization for Spinal Cord Arteriovenous Malformations: A Proposed Grading System

Neurosurgery 98:786–798, 2026

This study proposes a four-parameter grading system to stratify angioarchitectural complexity of spinal cord arteriovenous malformations (SCAVMs) and compares clinical outcomes of microsurgery versus endovascular embolization across five grades in a 714-patient multicenter cohort. The grade sums points for metameric manifestation, lesion diameter ≥2 cm, anterior sulcal artery supply, and lesion depth, predicting incomplete resection with strong ROC (receiver-operating characteristic) performance.

Results show embolization as the preferred primary treatment owing to lower immediate risk, while microsurgery achieves higher complete obliteration for low-grade lesions (scores 0–1) but carries greater treatment-related deterioration and worse long-term prognosis for higher grades (scores 2–4). Recommendations prioritize embolization, reserving microsurgery for select low-grade or high-risk patients when embolization fails.

Study aim Compare outcomes of microsurgery vs endovascular embolization for SCAVMs by introducing a grading system that stratifies angioarchitectural complexity to enable fairer comparisons.

Cohort & design Retrospective multicenter analysis of 714 SCAVM patients treated (2007–2022); 308 received microsurgery (often after failed/partial embolization) and 406 received exclusive embolization.

Grading system (0–4 points) One point each for anterior sulcal artery supply, metameric manifestations, maximum lesion diameter ≥2 cm, and embedded (deep) lesion depth; total score defines grade.

Predictors basis & performance The four grading variables were independent predictors of incomplete resection in microsurgical cases, and the score showed strong ROC discrimination in modeling and validation groups (AUC ≈ 0.83).

Overall treatment tradeoff Microsurgery achieved a higher complete obliteration rate (61.7% vs 24.4%) but had higher treatment-related deterioration (19.8% vs 4.2%) and higher poor prognosis at last follow-up (52.3% vs 36.2%) than exclusive embolization.

Low grades (0–2) obliteration For scores 0–2, microsurgery produced significantly higher complete obliteration than embolization; for scores 3–4, complete obliteration rates were similar between methods.

Long-term deterioration & prognosis by grade Long-term clinical deterioration after embolization was higher for score 1 (significant) and also higher for score 0 (not significant); for scores 2–4, long-term deterioration risk was comparable, while poor prognosis was generally worse with microsurgery except score 0 (similar).

Treatment strategy Embolization should be the primary approach for SCAVMs; microsurgery is an alternative if embolization fails to fully obliterate lesions in score 0 (recommended) and selected 1-point patients (optional, especially higher clinical risk), but not first-line for scores 2–4.

Pineal cyst surgery beyond morphology: a critical evaluation of a consecutive surgical series

Acta Neurochirurgica (2026) 168:85

This study evaluates surgical management of symptomatic pineal cysts in a consecutive single-center cohort, comparing microsurgical, endoscopic, and stereotactic techniques. Radiological measures — notably aqueduct diameter and predominant cyst expansion — were analyzed alongside clinical outcomes using the Chicago Chiari Outcome Scale, showing durable benefit when surgery is guided by clinicoradiological criteria.

Findings indicate aqueduct narrowing and anterior expansion better predict positive postoperative outcomes than cyst size alone. Each surgical approach demonstrated specific indications: microsurgery for suspicious lesions, endoscopy for hydrocephalus/anterior compression, and stereotactic drainage for deep or high-risk cases, with overall high rates of sustained improvement.

Clinical problem: Surgical management of pineal cysts is especially controversial in non-hydrocephalic symptomatic patients because clinical–radiological correlations are inconsistent and many studies rely mainly on size/morphology for decisions.

Study design: Retrospective single-center cohort of 46 symptomatic pineal cyst patients (2008–2024), comparing surgical (n=18) vs non-surgical (n=28) groups and analyzing radiological markers (e.g., cyst dimensions, aqueduct diameter, predominant expansion) alongside outcomes measured by CCOS over time.

Key differentiators for surgery: Compared with non-surgical patients, surgical patients had larger cysts, narrower aqueducts (0.9 vs 1.6 mm, p<0.001), and much more frequent predominant anterior expansion (67% vs 7%, p<0.001).

Overall outcomes: After surgery, 94% achieved good/excellent CCOS (≥12) at 12 months, and 93% maintained good/excellent outcomes at long-term follow-up (mean 62 months).

Predictors: Aqueduct diameter was more closely associated with outcome than pineal cyst size; neither cyst volume nor hydrocephalus consistently predicted postoperative outcome.

Technique comparison: Microsurgical resection (n=12) had favorable long-term outcomes (mean CCOS 14.9) but the highest complication rate (3 patients) and the highest recurrence of headache despite total excision.

Endoscopic approach: Endoscopic fenestration + ventriculostomy (n=3) produced the best long-term outcomes (mean CCOS 15.7) with no recurrences reported.

Stereotactic option: Stereotactic drainage + Rickham reservoir (n=3) achieved stable decompression but lower long-term CCOS (mean 13.0) than other approaches.

The effect of paraspinal sarcopenia on postoperative sagittal balance: a multivariate analysis following multilevel lumbar fusion surgery

The Spine Journal 26 (2026) 709−719

This clinical study examines how paraspinal sarcopenia influences long-term sagittal alignment and functional outcomes after multilevel posterior lumbar interbody fusion. Using preoperative MRI/CT and serial radiographs, muscle cross-sectional area, fat infiltration, and spinopelvic parameters were measured to compare sarcopenic and nonsarcopenic patients over at least two years.

Results show multifidus atrophy and fatty infiltration, plus inadequate preoperative lumbar and segmental lordosis, independently predict postoperative sagittal imbalance and worse pain and disability. The authors recommend preoperative paraspinal muscle assessment, nutritional and rehabilitation optimization, and tissue-sparing techniques to improve long-term outcomes.

Study aim: Assessed how paraspinal sarcopenia affects long-term sagittal alignment and persistent pain/disability after multilevel posterior lumbar interbody fusion (PLIF), and identified risk factors for postoperative sagittal imbalance.

Design & cohort: Retrospective single-institution study of 213 multilevel PLIF patients with imaging follow-up through ≥2 years; sarcopenic (n=69) vs nonsarcopenic (n=143/144) groups were compared.

Sarcopenia definition: Grouping based on psoas muscle index (MI) at L3 with thresholds <6.36 cm²/m² (men) and <3.92 cm²/m² (women).

Key measurements: Quantified L3 psoas/erector spinae/multifidus muscle MI, fat infiltration (Goutallier grading), and muscle density (CT HU); tracked spinopelvic parameters including LL, SL, PT, PI-LL, SVA plus VAS and ODI outcomes.

Muscle differences by group: Sarcopenic patients had lower muscle indices and higher fat infiltration (especially erector spinae and multifidus), with no significant difference in muscle density reported.

Alignment & outcomes: Sarcopenic patients showed worse long-term sagittal alignment at final follow-up (differences in LL, SL, PT, PI-LL, SVA) and worse long-term VAS and ODI scores, despite similar preoperative clinical scores.

Independent risk factors: Multifidus atrophy (lower MMI) and multifidus fat infiltration plus insufficient preoperative LL and SL were independent predictors of long-term postoperative sagittal imbalance; psoas, erector spinae, and other balance parameters were not independently associated.

Practical implication: Better sagittal-balance maintenance was associated with larger paraspinal MI, reduced fat infiltration, and favorable preoperative LL/SL, supporting preoperative evaluation of muscle health, nutritional status, and alignment.

Risk Factors and Reoperation Rate in Revision Lumbar Disc Herniation Surgery: A Systematic Review and Meta-Analysis of 1,031,348 Patients

Global Spine Journal 2026, Vol. 16(3) 1633-1647

This systematic review and meta-analysis examines reoperation rates and associated risk factors following primary lumbar disc herniation surgery across 25 studies totaling 1,031,348 patients. Pooled reoperation rate was 8.5% overall (adjusted to 10.3% for publication bias), with rates varying by follow-up: 4% at ≤1 year, 11.1% at 1–5 years, and 8.8% beyond 5 years.

Key risk factors identified include smoking, older age, diabetes, and large annular defects, while sex was not significant. The review highlights heterogeneity across study designs and follow-up durations, recommends careful patient selection, extended conservative management or closer surveillance for high-risk patients, and calls for trials comparing revision techniques.

Objective Estimate the reoperation rate after lumbar disc herniation surgery and identify associated risk factors.

Evidence base 25 studies (including observational studies and 3 RCTs) totaling 1,031,348 patients were included.

Overall reoperation rate Pooled reoperation rate was 8.5% (95% CI 6.2%–11.6%); after trim-and-fill adjustment for publication bias it was 10.3% (95% CI 7.6%–14.0%).

Follow-up pattern Reoperation rates differed by follow-up duration: 4% at ≤1 year, 11.1% at 1–5 years, and 8.8% at >5 years (significant subgroup differences).

Smoking risk Smoking was associated with higher odds of reoperation (OR 1.39, 95% CI 1.09–1.78).

Age risk Older age was associated with higher odds of reoperation (OR 1.52, 95% CI 1.25–1.85).

Annular defect risk Larger annular defect size was associated with higher odds of reoperation (OR 2.19, 95% CI 1.07–4.48).

Other factors Diabetes and certain surgical techniques were linked to higher reoperation risk in individual studies; sex was not a significant predictor (OR 1.22, 95% CI 0.96–1.55).

Treatment strategies, complications, and outcomes in spontaneous cerebellar hemorrhage

Acta Neurochirurgica (2026) 168:99

This single-center observational study examines treatment strategies, complications, and outcomes in 194 adults with spontaneous cerebellar hemorrhage (sCH) managed at a Swedish neurointensive care unit between 2008–2024. It compares conservative care, external ventricular drainage (EVD) alone, and combined hematoma evacuation with suboccipital decompression plus EVD, reporting short- and long-term mortality, functional outcome at discharge, and procedure-related complications.

Key findings show that conservative management often succeeds for neurologically stable patients with moderate hematomas (>15 mL), while combined evacuation/decompression with EVD is safe and effective for more severe presentations; EVD alone can suffice for selected hydrocephalus-predominant cases. Age, admission neurological status (GCS M), and hematoma volume independently predict 6-month mortality and functional outcome.

Study design Retrospective single-center cohort of adults with primary spontaneous cerebellar hemorrhage treated in a neurointensive care unit in Uppsala, Sweden (2008–2024), comparing conservative vs surgical management and analyzing predictors of 6‑month mortality and discharge functional outcome (GODS).

Treatment selection About half of 194 patients underwent surgery; surgically treated patients typically had worse neurological status, larger hematoma volumes, and more posterior fossa mass effect (e.g., fourth ventricle compression/hydrocephalus/IVH).

Conservative strategy for stable moderate-large bleeds In awake/stable patients with hematomas >15 mL initially managed conservatively, 78% did not need delayed surgery and most achieved favorable outcomes.

Surgical approach and safety Combined hematoma evacuation with suboccipital decompression plus EVD was associated with low complication rates and low early mortality in this cohort.

EVD-only option in selected cases Some patients with hydrocephalus and smaller hemorrhages were successfully treated with EVD alone, suggesting this may suffice when hydrocephalus predominates without dominant infratentorial mass effect.

Outcomes Overall mortality was 11% at discharge and 28% at 6 months; discharge outcomes differed by treatment group (higher early mortality but higher favorable discharge outcome in conservatively managed patients), while 6‑month mortality was similar between groups.

Key prognostic factors Age, neurological status (GCS motor score), and hematoma volume independently predicted 6‑month mortality; GCS motor score and hematoma volume independently predicted favorable discharge outcome (GODS > 3).

Clinical implication Favorable outcomes were achievable even in elderly patients; conservative care fit neurologically stable patients with moderate volumes, while surgery/EVD pathways were used for more severe presentations or deterioration.

Simple Microvascular Decompression for Hemifacial Spasm Caused by Dolichoectatic Vertebral Artery

Operative Neurosurgery 30:606–609, 2026

This operative case report describes a straightforward microvascular decompression (MVD) technique for hemifacial spasm (HFS) caused by a dolichoectatic vertebral artery (VA), emphasizing translocation and padding of the root entry zone (REZ) with Teflon pledgets. The 67-year-old patient underwent retrosigmoid craniotomy with safe mobilization of the VA, achieving immediate and sustained symptom resolution despite residual distal contact.

The authors compare REZ-focused decompression to more complex options such as sling transposition and binder-ring bypass, arguing that limited REZ decompression offers a simpler, lower-risk solution when complete arterial mobilization is unfeasible. Operative nuances, monitoring, outcomes, and literature context are provided to support this effective, pragmatic approach.

Condition Hemifacial spasm can be caused by neurovascular compression of the facial nerve at the root entry zone (REZ), and a tortuous/dolichoectatic vertebral artery (VA) is a rare culprit that makes complete decompression challenging.

Standard MVD outcomes Typical microvascular decompression for HFS (usually targeting AICA/PICA) provides >90% symptomatic relief at 1-year follow-up with notable complications including hearing loss (2.3%) and facial palsy (0.9%).

Limitations of sling transposition Macrovascular decompression with a Teflon/Gore-Tex sling can be effective but may be infeasible when anchoring is poor or when artery manipulation risks kinking/disrupted blood flow or distal nerve stretching.

Higher-complexity alternative The “binder ring” approach (VA transection, relocation, and reanastomosis) is described but is lengthy, requires temporary occlusion, and carries elevated risk (e.g., brainstem/cerebellar infarct).

Case presentation A 67-year-old woman with debilitating left HFS had a large tortuous VA abutting the facial nerve REZ; after retrosigmoid craniotomy, mobilization relieved REZ compression but residual distal cisternal contact persisted.

Key technique Simple REZ-focused decompression was achieved by mobilizing the VA as safely feasible and placing Teflon pledgets to pad the vessel away from the REZ; complete distal nerve decompression was not feasible and further manipulation was avoided due to risk to perforators/7th–8th nerve complex.

Outcome Despite residual cisternal segment contact, symptoms resolved immediately post-op and remained absent at 12-month follow-up after REZ decompression alone.

Core conclusion Targeting decompression of the REZ alone can be a simple, effective strategy for HFS due to dolichoectatic VA, potentially avoiding more complex and riskier techniques when full nerve-complex decompression is not achievable.

Which spine surgeries belong in the ambulatory surgical center?

Neurosurg Focus 60(4):E2, 2026

This study uses time-driven activity-based costing (TDABC) to quantify true costs of common cervical and lumbar spine procedures performed in an outpatient hospital setting and compares these costs to Medicare ambulatory surgical center (ASC) reimbursement. Findings show microdiscectomy, lumbar laminectomy/decompression, and ACDF most often fall below Medicare ASC reimbursement, while endoscopic discectomy and posterior lumbar fusion frequently exceed reimbursement.

The analysis identifies supplies and personnel as primary cost drivers, highlights heterogeneity in Medicare ASC facility fees that do not reflect procedural complexity or number of levels, and argues that reimbursement reform is needed to expand the range of spine procedures economically feasible in ASCs.

Objective Identify spine procedures that are economically suitable to move from an outpatient hospital setting to an ambulatory surgical center (ASC) by comparing true costs (via TDABC) with Medicare ASC reimbursement.

Methods Retrospective cohort (2020–2024) of outpatient hospital spine cases with length of stay ≤ 1 day; procedures: cervical disc arthroplasty, ACDF, lumbar laminectomy/decompression, microdiscectomy, endoscopic discectomy, and posterior lumbar fusion; primary outcomes were total costs and proportion of cases with cost below Medicare reimbursement; regression adjusted for age, sex, BMI, and number of levels.

Costing approach (TDABC) Episode mapped across preop, intraop (wheels-in to wheels-out), and recovery phases; costs included supplies (consumables, implants, meds), personnel time (per-minute rates by role), and overhead.

Key cervical finding ACDF was more often below corresponding ASC reimbursement than cervical disc arthroplasty (71.8% vs 40.0%); adjusted odds favored ACDF (OR 5.3, 95% CI 3.0–9.4).

Key lumbar cost levels Mean lumbar episode cost was $4,640 ± $6,475; posterior lumbar fusion had the highest mean cost ($25,042 ± $15,645) and microdiscectomy the lowest ($3,233 ± $2,142).

Key lumbar viability finding Microdiscectomy (95.3%) and laminectomy/decompression (94.5%) most often cost less than reimbursement; endoscopic discectomy (31.0%) and posterior lumbar fusion (30.0%) were least often below reimbursement; adjusted odds were higher for laminectomy/decompression (OR 6.0) and microdiscectomy (OR 4.7), and far lower for endoscopic discectomy (OR 0.01) and fusion (OR 0.02).

Conclusions (procedures best suited for ASC under current payments) Microdiscectomy, lumbar laminectomy/decompression, and ACDF appear most economically suitable for transition from hospital outpatient to ASC in existing payment structures.

Reimbursement implication Broader feasibility in ASCs likely requires reimbursement reform, given mismatches between procedural complexity/resource use and Medicare ASC payment patterns.

How Do Neurosurgeons Cope With Complications? Results of a Nationwide Survey

Neurosurgery 98:752–764, 2026

This study reports results of a nationwide survey assessing how neurosurgeons emotionally respond to surgical complications and which coping and defense mechanisms they use. It quantifies prevalence of patient harm, emotional impact, common adaptive and maladaptive behaviors, and associations with career effects such as limiting practice or contemplating leaving neurosurgery.

Findings show frequent use of intellectualization, humor, and affiliation alongside maladaptive behaviors that strongly predict career doubt and short-term practice changes, with junior surgeons reporting more coping strategies. The authors recommend institutional support, targeted interventions, and further longitudinal research to improve surgeon well-being and patient care.

Prevalence of serious complications Patient harm was commonly experienced: minor harm (87.3%), temporary harm (80.3%), long-term harm (79.6%), and patient death (58.4%).

Emotional impact Complications had a significant (55.6%) or profound (38.0%) immediate emotional impact, with long-term impact significant for 44.4% and profound for 12.7%.

Persistent preoccupation Respondents thought about complications weekly (41.5%) or daily (22.5%).

Common adaptive coping Frequent adaptive strategies included using errors as teaching opportunities (80.3%), speaking with a spouse/significant other (65.5%), exercise (61.9%), speaking with a mentor (51.4%), and speaking with friends (49.3%).

Common maladaptive coping Common maladaptive responses included sleep disturbances (52.8%), social withdrawal (38.0%), overeating (25.4%), procrastination (23.2%), and excessive alcohol consumption (11.3%).

Defense mechanisms used The most common defense mechanisms were intellectualization (68.3%) and humor (64.1), along with affiliation (61.2%) and altruism (53.5%).

Career/practice consequences tied to maladaptive coping Maladaptive coping was associated with higher odds of considering leaving the profession (OR 5.84) and limiting practice in the short term (OR 3.08).

Notable subgroup findings Junior neurosurgeons used more adaptive and maladaptive coping mechanisms than senior neurosurgeons, and academic neurosurgeons were more likely than private practitioners to question their clinical abilities (OR 2.68).

Prediction of Diffuse High-Grade Glioma Survival Outcomes Using Preoperative Whole-Brain Tractography–Based Resectability Metrics

Neurosurgery 98:836–847, 2026

This study presents novel whole-brain tractography (WBT)–derived resectability metrics—resectability index (RI) and unresectable tumor volume (UTV), plus modified versions mRI and mUTV—calculated from preoperative diffusion imaging to estimate how much of diffuse high-grade gliomas (HGG) can be safely resected. Metrics are derived by quantifying tumor overlap with critical white-matter tracts and deep structures, and compared with conventional postoperative measures.

Using retrospective data from 146 tumors (84 with WBT), mRI and mUTV strongly predicted biopsy versus resection and correlated with extent of resection, residual tumor, and overall survival. Accelerated failure time models incorporating mUTV/mRI provided accurate preoperative survival predictions, outperforming conventional metrics in postoperative models.

Problem: Extent of resection (EOR) predicts survival in diffuse high-grade glioma but is only measurable postoperatively, limiting preoperative decision-making.

Approach: Preoperative whole-brain tractography (WBT) was used to quantify tumor overlap with eloquent tracts and deep structures to estimate resectability before surgery.

Metrics: Unresectable tumor volume (UTV) = tumor overlap with eloquent tracts + deep structures; Resectability index (RI) = (preop tumor volume − UTV) / preop tumor volume.

Modified metrics: mUTV/mRI focused only on corticospinal tract and left arcuate fasciculus, and performed better than unmodified metrics in several analyses.

Surgical decision prediction: mRI (AUROC 0.953) and mUTV (AUROC 0.854) accurately predicted biopsy vs resection, with optimal cutoffs mRI 0.75 and mUTV 2.5 cm³.

Survival separation: Tumors with mRI > 0.65 vs ≤ 0.65 showed the largest median overall survival difference (not reached vs 82 days, P < .0001).

Best preop survival model: A log-logistic accelerated failure time (AFT) model using only preoperative covariates achieved validated C-index 0.788, with mUTV an independent predictor of overall survival (P = .008).

Overall conclusion: Preoperative WBT-based resectability metrics approximate postoperative EOR/residual tumor volume and can strongly predict survival outcomes after biopsy or resection.

Global economic differences in modern glioblastoma care – a systematic review

Acta Neurochirurgica (2026) 168:89

This systematic review quantifies global cost and cost-effectiveness differences in contemporary glioblastoma (GBM) care, analyzing 21 studies standardized to 2024 USD. It reports extreme heterogeneity in direct medical costs—from about $18,908 in India to $356,481 in the United States—and identifies inpatient care and adjuvant therapies as primary cost drivers in high-income settings.

Economic models reveal that the full Stupp protocol often exceeds willingness-to-pay thresholds in middle- and low-income countries, while surgical resection and 5‑ALA fluorescence-guided surgery show relatively favorable cost-effectiveness. The authors call for standardized cost reporting and inclusion of societal perspectives to improve cross-country comparisons and policy decisions.

Purpose Quantified global differences in costs and cost-effectiveness of modern Stupp-protocol–based glioblastoma care via a systematic review.

Methods Searched PubMed/MEDLINE/Cochrane to Dec 1, 2025 using (Glioblastoma OR GBM) AND (costs OR cost-effectiveness OR economic burden); included studies with quantifiable economic outcomes from 2005 onward, yielding 21 eligible studies.

Standardization Converted all reported costs to 2024 USD by inflating with country-specific CPI to 2024 and converting using 2024 PPP rates.

Direct costs range Direct medical costs were highly heterogeneous, from about $356,481 (United States) to about $18,908 (India), across 15,547 real-world patients.

Cost drivers (Western systems) Adjuvant treatment and inpatient care were major contributors to direct medical costs in western countries (with inpatient care and radiotherapy prominent in US analyses).

Stupp protocol affordability The Stupp protocol exceeded willingness-to-pay thresholds in middle-income/resource-limited settings, indicating substantial financial burden in those contexts.

TTF cost-effectiveness variability Tumor treating fields (TTF) showed very high ICERs in France (≈ $862k–$940k per LYG) and $252,590 per LYG in the US, but a more favorable estimate of $45,813.91 per QALY in China.

Key implication Uniform, standardized cost reporting is needed to better compare cost-effectiveness across countries; economic findings also underscore the role of surgery as a cost-effective component of modern GBM management.

Low Posterior Electromyographic Threshold and Functional Outcomes After L4-5 Lateral Lumbar Interbody Fusion

Operative Neurosurgery 30:566–570, 2026

This single-institution retrospective study evaluates whether low posterior electromyography (EMG) stimulation thresholds during lateral L4-5 lumbar interbody fusion (LLIF) correlate with postoperative femoral nerve motor or sensory neurapraxia. Forty-two lateral-position single-level L4-5 LLIFs with neuromonitoring data showed no significant association between posterior EMG threshold or retractor time and transient postoperative anterior thigh numbness or weakness.

The cohort experienced transient sensory neurapraxia in 38% at six weeks that resolved by six months; only one patient had temporary motor neurapraxia. Limitations include small sample size, retrospective design, and short follow-up, leading authors to conclude no demonstrable link between posterior EMG threshold and plexus injury in this series.

Context: In L4-5 transpsoas LLIF, the retractor is placed near the lumbar plexus; directional EMG stimulation thresholds are used intraoperatively to estimate nerve proximity and potentially reduce injury risk.

Objective: Assessed whether posterior EMG stimulation threshold was associated with lumbar plexus injury/neurapraxia after single-level L4-5 LLIF performed in the lateral position.

Design/criteria: Retrospective, single-institution review of single-level L4-5 LLIF (Jan 2019–May 2022) with available neuromonitoring thresholds and retractor time; excluded cases with additional levels or missing monitoring data.

Cohort/intraop metrics: 42 patients (mean age 66 years); mean retractor time 12.4 minutes; mean posterior EMG threshold 10.4 mA.

Neurologic outcomes: Femoral motor neurapraxia occurred in 1 patient (2%); sensory neurapraxia (anterior thigh numbness) occurred in 16 patients (38%) at 6 weeks and resolved to 0% by 6 months.

Main finding: Posterior EMG threshold was not associated with postoperative motor neurapraxia or sensory neurapraxia at 6 weeks (including logistic regression showing OR 1.00; P=.98 for thigh numbness).

Other associations: No significant correlation between posterior EMG threshold and retractor time (Spearman ρ=0.11; P=.50) or postoperative ODI (ρ=0.17; P=.33).

Notable case/interpretation: The single motor neurapraxia case had 27-minute retractor time with posterior EMG 5 mA and recovered by 6 months; median retractor time in the cohort was low (10.8 minutes), limiting conclusions about longer retraction durations.

When the saline hits your brain: effects of standard irrigation solutions on neural function

J Neurosurg 144:995–1002, 2026

This report examines the physiological consequences of commonly used neurosurgical irrigation fluids, highlighting effects on synaptic transmission, vascular responses, spreading depolarization, and long-term cellular toxicity. Preclinical brain-slice and animal models demonstrate that normal saline, lactated Ringer’s, and PlasmaLyte can impair neuronal function, alter electrolytes and pH, and worsen recovery compared with artificial cerebrospinal fluid (aCSF).

Clinical observations and preliminary trials mirror experimental findings: aCSF associates with improved postoperative neurophysiology, reduced chronic subdural hematoma recurrence, and better outcomes after aneurysm surgery. The authors advocate prioritizing physiologically matched irrigation solutions and propose targeted clinical trials to evaluate aCSF or electrolyte-optimized fluids across neurosurgical and ICU applications.

Risk premise Nonphysiological neurosurgical irrigation solutions may be an underrecognized contributor to impaired neurological recovery and potentially long-term impairment.

High-volume exposure Irrigation volumes commonly exceed 1 L intraoperatively, and ICU intraventricular irrigation around 60 mL/hr can total ~1.5 L/day for multiple days—large relative to ~125 mL total CSF volume and ~500 mL/day CSF production.

Composition mismatch Commonly available fluids (normal saline, lactated Ringer’s, PlasmaLyte) are roughly iso-osmolar to CSF but differ substantially from CSF in pH and key ions/metabolites (e.g., NS lacks bicarbonate, Ca²⁺, Mg²⁺ and is acidic; LR lacks Mg²⁺ and is acidic).

Synaptic suppression (NS) Superfusion with normal saline rapidly abolishes excitatory postsynaptic potentials; adding Ca²⁺ only partially restores activity, implying multiple missing factors beyond Ca²⁺.

Mechanisms (pH/Mg²⁺ effects) Low pH in NS and LR can depress AMPA/NMDA receptor currents, while LR’s lack of Mg²⁺ can cause transient hyperexcitability followed by loss of synaptic transmission with continued exposure.

Spreading depolarization vulnerability After a spreading depolarization, tissue recovers fully in aCSF but shows profound, persistent suppression of synaptic transmission in LR (even with glucose/oxygen supplementation), with LR also prolonging the depolarization signal.

Preclinical harms In animal and cell models, NS and LR are associated with worse edema/cellular damage than aCSF, and ventriculocisternal NS infusion in rats caused seizures, death, and cortical/CA1 cell death not seen with aCSF.

Clinical signals favor aCSF In endoscopic and other neurosurgical contexts, NS irrigation has been linked to CSF acidification and decreases in glucose/calcium, and comparative studies/meta-analyses report better outcomes with aCSF (e.g., reduced chronic subdural hematoma recurrence; improved early recovery after aneurysm clipping; faster BAEP recovery in microvascular decompression).

Outpatient minimally invasive transforaminal lumbar interbody fusion performed at a single ambulatory surgery center: the Semmes Murphey Clinic experience

Neurosurg Focus 60(4):E5, 2026

This study reports outcomes from 179 patients undergoing single-level minimally invasive transforaminal lumbar interbody fusion (miTLIF) at a single ambulatory surgery center (ASC) between 2012–2024. It presents demographics, surgical details, complications, and validated patient-reported outcomes with 2-year follow-up showing sustained pain reduction, functional improvement, and high satisfaction.

The authors detail selection criteria, perioperative technique using tubular retractors and percutaneous pedicle screws, low complication and 90-day readmission/reoperation rates, and discuss economic and policy implications for ASC-based lumbar fusion care.

Objective Report 2-year outcomes for outpatient minimally invasive TLIF (miTLIF) performed at a single ambulatory surgery center (ASC).

Cohort 485 single-level miTLIFs were performed at the ASC (2012–2024); 179 registry-enrolled patients were analyzed (mean age 54; BMI mean 31).

Selection ASC eligibility exclusions included BMI > 50, weight > 350 lb, cardiac disease not cleared “low risk,” ASA class IIIb or above, family history of malignant hyperthermia, or inability to ambulate; Medicare primary insurance was also excluded for reimbursement reasons.

Disposition 98.3% were discharged within a few hours; 1.1% observed < 23 hours for pain control; 0.56% required hospital transfer for new-onset atrial fibrillation (treated and discharged within 23 hours).

Patient-reported outcomes Mean scores improved from baseline to 3 months and remained improved through 2 years (e.g., back pain NRS 6.98→2.40 at 3 months and 2.86 at 2 years; ODI 44.14→19.37 at 3 months and 13.87 at 2 years; EQ-5D 0.56→0.81 at 3 months and 0.82 at 2 years).

Complications Durotomy occurred in 1.7% (treated with fibrin glue, discharged within hours); superficial surgical site infection 0.56% (oral antibiotics only); postoperative hematoma 0.56%; urinary tract infection 0.56%.

Readmissions/reoperations (90-day) 2.2% readmissions and 1.1% reoperations within 90 days (including hardware failure and delayed hematoma).

Conclusion For carefully selected patients, ASC-based miTLIF showed significant, durable PROM improvement with acceptably low complications, readmissions, and reoperations.

Impact of lateral plate and screw fixation on long-term radiographic subsidence in lateral lumbar interbody fusion

J Neurosurg Spine 44:493–497, 2026

This clinical study evaluates long-term radiographic subsidence after lateral lumbar interbody fusion (LLIF), comparing stand-alone procedures with those augmented by lateral plate and screw fixation. Retrospective analysis of 146 patients (219 levels) with ≥1-year CT follow-up shows lateral plating significantly reduced subsidence odds, while 3D-printed porous titanium cages trended toward lower subsidence than PEEK.

Results note similar reoperation rates between groups, no grade III subsidence, and rare adverse events including one delayed vertebral fracture with plating; methodology included multivariate logistic regression and Marchi subsidence grading. Conclusions support lateral plate and screw fixation, particularly with porous titanium cages, as protective against severe radiographic subsidence.

Objective Assess whether adding lateral plate and screw fixation changes the long-term rate/grade of radiographic cage subsidence after LLIF (excluding posterior instrumented fusion).

Design/Population Retrospective review (2014–2022) of degenerative lumbar spondylosis LLIF cases at two centers; required ≥1-year postoperative CT; 146 patients/219 levels (45% plated, 55% stand-alone).

Subsidence grading Long-term imaging graded by Marchi criteria (grade 0: 0%–24% disc height loss; I: 25%–49%; II: 50%–74%; III: 75%–100%); no intraoperative subsidence included.

Main finding (plating effect) Lateral plate + screws was significantly associated with reduced long-term radiographic subsidence (multivariable OR 0.484, p = 0.006).

Severity pattern All grade II (severe) subsidence cases occurred in the stand-alone LLIF group (4 patients); no grade III subsidence observed.

Cage material trend 3D-printed porous titanium cages trended toward lower subsidence versus PEEK but did not reach statistical significance (OR 0.401, p = 0.071).

Reoperation/fusion No significant difference in reoperation rate between plated and stand-alone groups; radiographic fusion rates were similar (83.1% plated vs 86.4% stand-alone; p = 0.58).

Noted complications/implant details One lateral-plate patient had a delayed vertebral body fracture; plated cases used 18-mm-wide cages, while nearly all stand-alone cases used 22-mm-wide cages.

Quantitative MRI Tractography of White Matter Tracts After Tumor Craniotomy Surgery: Comparative Analysis Between Tubular Retractor and Open Craniotomy Surgery

Operative Neurosurgery 30:525–532, 2026

This study compares quantitative diffusion MRI tractography outcomes after deep-seated brain tumor resections using tubular retraction (TR) versus open craniotomy (OC) with spatula/cottonoid retraction. In a matched cohort of 20 patients, TR achieved comparable extent of resection with improved postoperative fractional and geodesic anisotropy metrics and a greater mean increase in Karnofsky Performance Score.

Methods include pre/postoperative 1.5T DTI, autosegmented tractography of ipsilateral tracts, and statistical comparison of FA, GA, diffusivity metrics, and tract volume. Results suggest TR reduces certain retraction-related white matter distortion without worsening diffusivity markers, supporting TR as a viable technique for deep subcortical lesions with potential functional benefit.

Goal Quantitatively compare cerebral retraction–related white matter tract changes after deep-seated tumor surgery using tubular retraction (TR) vs open craniotomy (OC) with spatula retraction via diffusion MRI tractography metrics.

Design Retrospective matched-pair analysis of 20 patients (10 TR vs 10 OC), matched by tumor size, depth, and age; all surgeries performed by a single surgeon.

Tractography process/metrics Pre- and postoperative DTI tractography (1.5T MRI) autosegmented ipsilateral supratentorial tracts; quantified FA, GA, MD, RD, AD, and tract volume across specified tracts (e.g., corticospinal, arcuate/SLF, ILF, IFOF, fornix, uncinate, optic radiations).

Extent of resection Resection was comparable between groups (TR 90.4% vs OC 94.8%, P = .395).

Functional outcome Change in Karnofsky Performance Score (KPS) favored TR (mean +11 points) vs OC (no change), P = .035.

Key quantitative findings Postoperative FA and GA differed significantly in favor of TR (FA 0.322 TR vs 0.029 OC, P = .011; GA increased in TR 0.441 vs decreased in OC 0.411, P = .012).

Other imaging metrics Postoperative tract volume was higher in TR than OC (14.9 cm³ vs 10.6 cm³, P = .036), while diffusivity metrics (MD, RD, AD) were broadly comparable between cohorts.

Conclusion TR offers a viable approach for deep-seated tumors with similar resection extent while mitigating some components of retraction injury as reflected by quantitative tractography changes and improved KPS.

Stereotactic Radiosurgery Versus Observation in Small- and Medium-Sized Vestibular Schwannoma Patients With Normal Hearing: A Retrospective International Multicenter Study

Neurosurgery 98:887–894, 2026

This multicenter retrospective study compares stereotactic radiosurgery (SRS) with observation (OBS) for small-to-medium vestibular schwannomas (Koos I–II) in patients presenting with normal (AAO‑HNS class A) hearing. Propensity-score–matched cohorts (57 SRS, 57 OBS) were analyzed for serviceable hearing preservation (SHP), tumor control (TC), and cranial nerve outcomes over median follow-ups of 49 and 37 months.

Results show SRS achieved markedly superior tumor control (≈98% at 5–10 years) while producing noninferior hearing outcomes versus observation (5‑year SHP: SRS 76.2% vs OBS 56.1%; difference not statistically significant). The authors conclude SRS is preferable for TC without compromising hearing, emphasizing individualized decision-making given study limitations.

Clinical question Comparison of stereotactic radiosurgery (SRS) vs observation (OBS) for small/medium Koos I–II vestibular schwannomas in patients with AAO-HNS class A (normal) hearing at presentation, focusing on hearing preservation and tumor control

Design Retrospective international multicenter study with propensity score matching (age, sex, tumor volume, PTA, SDS) yielding 57 SRS vs 57 OBS matched patients

Serviceable hearing preservation No statistically significant difference in long-term serviceable hearing preservation between SRS and OBS in the matched analysis (log-rank P = .17), despite numerically higher SRS rates

Hearing rates over time Matched-cohort 5-/9-year serviceable hearing preservation: SRS 76.2% / 42.4% vs OBS 56.1% / 16.8%

Class A hearing Class A preservation was similar: 57.9% (SRS) vs 52.6% (OBS) (P = .70)

Tumor control SRS achieved markedly superior tumor control (log-rank P < .0001); 5-/10-year tumor control: SRS 97.9% / 97.9% vs OBS 40.9% / 15.1%

Other clinical outcomes No significant matched-cohort differences in cranial nerve deficits, vestibulopathy, or composite CN/tinnitus worsening; tinnitus worsening trended higher with OBS (21.1% vs 8.8%) but was not significant (P = .066)

Overall conclusion SRS provided noninferior hearing outcomes while being significantly better for tumor control, supporting SRS as a favored option while still emphasizing individualized decision-making

Long-term tumor control after Gamma Knife radiosurgery for sporadic vestibular schwannoma

J Neurosurg 144:965–971, 2026

This clinical study evaluates long-term tumor control after single-fraction Gamma Knife stereotactic radiosurgery (SRS) for sporadic vestibular schwannoma in 749 adults treated from 2000–2022, reporting Kaplan–Meier control rates of 100%, 98%, 96%, 92%, and 91% at 1, 3, 5, 10, and 15 years respectively. Patient demographics, SRS dosing, and complication rates—including low persistent facial paresis—are summarized with statistical analysis and clear definitions for growth, pseudoprogression, and salvage.

The authors detail three post-SRS tumor behavior patterns, finding 13% pseudoprogression (mostly within 5 years) and 42 salvage treatments (median 3.7 years), and conclude that SRS offers durable control while emphasizing the need for prolonged surveillance and nuanced clinical decision-making about retreatment.

Objective Assess long-term efficacy of single-fraction stereotactic radiosurgery (SRS) as primary treatment for adult, treatment-naïve sporadic vestibular schwannoma (Gamma Knife), treated from 2000–2022.

Cohort 749 adults included; 76% had tumors extending into the cerebellopontine angle (CPA) at SRS; median age 62; 50% women; 99% had House-Brackmann (HB) grade I facial nerve function at SRS.

Long-term tumor control Tumor control after SRS remained high: 100% (1 yr), 98% (3 yr), 96% (5 yr), 92% (10 yr), and 91% (15 yr).

Radiosurgical failure/salvage 42 patients required salvage (35 microsurgery, 7 repeat SRS), median 3.7 years post-SRS; 3 salvage treatments occurred >10 years after SRS, indicating late failures can occur.

Risk factors Age, macrocystic tumor presence, and treated tumor volume were not significantly associated with risk of salvage in univariable analysis.

Post-SRS tumor patterns Three post-SRS behaviors were observed: (1) stability/shrinkage, (2) pseudoprogression (growth then stability/shrinkage), and (3) continued growth without stability at last follow-up.

Pseudoprogression timing 13% experienced pseudoprogression; all but 4 showed it by year 5 post-SRS, though some initial growth occurred later (e.g., 5.1–8.6 years) with subsequent stability on follow-up imaging.

Conclusion/implication SRS provides durable control through 15 years for most patients (91%), but ongoing long-term surveillance is needed because failures may occur even beyond 10 years and pseudoprogression can be seen out to ≥5 years.

Clinical Significance and Utility of Early Postoperative Computed Tomography Scan Head after Brain Surgery

Neurosurgery 98:810–817, 2026

This prospective single-center study assesses the clinical value of routine early (within 6 hours) postoperative CT scans in 339 adults after intracranial surgery, correlating immediate neurological status with CT findings and resulting management changes. Results show 97.3% had only expected postoperative changes, 2.7% had hematoma without mass effect, and none required surgical intervention; only six patients had medical management altered.

The authors conclude that routine early CT provides minimal benefit for extubated, neurologically stable or expected-deficit patients and advocate selective imaging for clinical deterioration or unreliable examinations, highlighting cost, radiation, and logistical considerations particularly relevant to resource-limited settings.

Aim Evaluate whether an early postoperative head CT within 6 hours after intracranial surgery changes patient management and assess its clinical utility.

Design/setting Single-center prospective cohort of 339 intracranial surgery patients; all received CT within 6 hours and were grouped clinically as no deficit, expected deficit, or unexpected deficit.

CT classification Imaging findings were categorized as postoperative changes only, operative site hematoma without mass effect, or hematoma with mass effect (with management options: no change, medical change, or surgery).

Key findings (imaging) 97.3% (330/339) showed postoperative changes only; 2.7% (9/339) had operative site hematoma without mass effect; 0% had hematoma with mass effect.

Key findings (management impact) 98.2% (333/339) had no change in management based on early CT; 1.8% (6/339) had a change in medical management; 0% required surgical intervention.

Neurological status distribution Postoperatively, 90.9% had no fresh deficit, 7.1% had an expected deficit, and 2.1% had an unexpected deficit.

Association signal Patients with unexpected neurological deficits were more likely to have abnormal CT findings (reported OR 6.22, wide CI, P = .193, not statistically significant).

Bottom line Early postoperative CT offers minimal benefit for extubated patients with no or expected deficits; CT should be reserved for clinical deterioration or unreliable neurological examination.