A recent Neurosurgery digest,
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Study Type: Technical note ("how I do it"); no patient cohort or comparative data reported.

Key Question: Can a dual-step burr hole combined with periosteal anchoring improve fixation of proximal ventricular catheters in VPS and Ommaya reservoir insertion?

Key Findings:

• Technique: a shallow outer burr hole seats a right-angle catheter guide, and a smaller central inner burr hole exposes the dura for catheter passage.
• The connector is sutured to preserved pericranium with nonabsorbable sutures, and the periosteal flap is then reapproximated.
• The authors propose this creates a multiplanar mechanical barrier against migration and kinking. No outcome data (migration, revision or infection rates, follow-up) are provided in the abstract.

Clinical Relevance: Proximal catheter migration and obstruction drive shunt revision burden in NHS practice, so a simple, low-cost fixation option may interest surgeons seeking to reduce avoidable reoperations.

Limitations: No reported patient numbers, outcomes or comparison with standard fixation, so the claimed robustness is unsubstantiated by clinical evidence.

Study Type: Mixed-methods evidence review: trial registry search, Cochrane database review, and survey of anaesthetists and neurosurgeons.

Key Question: Is there sufficient evidence to guide choice between local (± sedation) and general anaesthesia for cSDH surgery, and what would a definitive trial need to address?

Key Findings:

• Few high-quality studies exist, particularly RCTs, comparing LAS with GA in cSDH surgery.
• Existing literature and practitioner survey responses suggest LAS may give equivalent outcomes, but current studies are significantly confounded.
• All registered trials are single-centre; Cochrane reviews from other surgical fields highlight equipoise, trial design, and outcome selection as key barriers. The abstract gives no quantitative data (e.g. survey response numbers or effect sizes).

Clinical Relevance: cSDH commonly affects frail, comorbid patients, so a multicentre UK trial on anaesthetic technique is clearly needed, and this paper supports its feasibility and design considerations.

Limitations: Findings rest on a narrative review and survey rather than systematic synthesis; survey size, response rate, and representativeness are not reported in the abstract.

Study Type: Retrospective single-centre cohort study (n=246), with propensity-matched subgroup analysis.

Key Question: Is early post-operative pharmacological thromboprophylaxis safe, in terms of haematoma risk and VTE, after primary VP shunt insertion in adults?

Key Findings:

• 76.0% (187/246) received pharmacological prophylaxis (median post-operative day 1) alongside universal mechanical prophylaxis; one VTE (PE) occurred (0.4%).
• Routine imaging detected 12 haematomas (4.9%); 2 (0.8%) were clinically significant, including one ICH requiring evacuation.
• Prophylaxis was not associated with increased haematoma risk (unadjusted p>0.99; propensity-matched p=0.36).

Clinical Relevance: Supports early chemoprophylaxis after VP shunt insertion, where UK practice varies and guidance is limited, though it does not establish equivalence.

Limitations: With only one VTE and two clinically significant haematomas, the study is underpowered to detect meaningful differences in either outcome, and the retrospective single-centre design leaves residual confounding.

Study Type: Single-centre retrospective cohort study (n = 80).

Key Question: Does intracatheter thrombolysis with urokinase or tPA carry a different rebleeding risk after navigation-guided catheter evacuation of spontaneous supratentorial ICH?

Key Findings:

• Rebleeding: 26.7% (12/45) with tPA vs 5.7% (2/35) with urokinase (p = 0.032). Adjusted OR for tPA 5.03 (95% CI 1.12–22.64) after adjusting for IVH, onset-to-surgery time and baseline volume.
• Mean hematoma volume reduction at day 4 was similar between groups, but more variable with tPA.
• Early mRS and GCS changes favoured urokinase; concurrent IVH was a strong rebleeding risk factor.

Clinical Relevance: Relevant to UK units using or considering catheter-based MIS for ICH, where tPA is the usual agent and urokinase availability is limited; these data raise a safety signal but do not support practice change alone.

Limitations: Small, non-randomised sample with baseline imbalances (higher BP and larger volumes in the tPA group), only 14 rebleed events, and a very wide confidence interval, so residual confounding and imprecise effect estimates are likely.

Study Type: Systematic review and meta-analysis of observational studies (29 studies, 4,711 patients).

Key Question: How well do preoperative imaging-derived bone quality and paraspinal muscle metrics predict radiographic pedicle screw loosening after degenerative lumbar fusion?

Key Findings:

• Radiographic PSL occurred in 25.4%. Affected patients had lower HU (MD -24.7), lower CT-BMD (MD -28.05), lower DEXA T-scores (MD -0.18) and higher MRI VBQ (MD 0.46).
• Discrimination was moderate and similar across modalities (pooled AUC 0.71–0.76; meta-regression P = 0.08). Nomograms improved risk reclassification but had limited rule-in/rule-out capacity.
• Reduced psoas CSA was consistently associated with PSL; posterior paraspinal metrics were heterogeneous and largely non-significant.

Clinical Relevance: Opportunistic HU or VBQ from routine preoperative CT/MRI can support risk stratification and planning (e.g. augmentation strategy, optimisation) without extra imaging or DEXA, though none can serve as a stand-alone test.

Limitations: The composite PSL endpoint used inconsistent definitions and adjudication (radiograph vs CT), and radiographic loosening was not tied to clinically meaningful construct failure.

Study Type: Retrospective registry-based descriptive cohort study (Swespine, 2006–2024); no non-operative comparator.

Key Question: What are the longitudinal patient-reported outcomes of ACDF for neck pain presumed to arise from segmental dysfunction, in the absence of radiculopathy or myelopathy?

Key Findings:

• Of 36 patients (mean age 51, 50% male), MCID was achieved at 1 year in 55% (18/33) for NRS neck pain, 48% (15/31) for NDI and 53% (16/30) for EQ-5D.
• Improvement occurred mainly by 1 year, with no clear further gain to 10 years.
• Satisfaction was 64% at 1 year and 64–71% across all time points, despite heterogeneous PROM trajectories.

Clinical Relevance: Roughly half of patients reached MCID, and the authors do not support surgery for isolated axial neck pain, which is relevant to UK referral and surgical selection decisions where evidence is scarce.

Limitations: Very small sample, no controls, registry-defined diagnosis and likely selection bias preclude causal inference.

Study Type: Retrospective single-centre diagnostic accuracy study (n=130, selected from 173 screened records).

Key Question: How accurately do general pathology and specialist neuropathology identify high-grade glioma, using EPIC DNA methylation classification as the reference standard?

Key Findings:

• General pathology: sensitivity 79%, specificity 100%, NPV 62%, accuracy 84%. All 20 errors were false negatives (13 called low-grade glioma, 5 non-neoplastic, 2 other lesions).
• Specialist neuropathology: sensitivity 100%, specificity 97%, NPV 100%, accuracy 99%. Three discordances: two HGGs refined to glioblastoma, IDH-wildtype, and one case called tumour on histology was tumour-free on methylation.
• Methylation profiling refined classification beyond binary HGG status.

Clinical Relevance: Under-diagnosis of HGG outside specialist neuropathology could delay or alter adjuvant treatment, supporting referral of suspected HGG specimens to neuropathology centres within NHS pathways.

Limitations: The cohort was selected (130 of 173 had complete results) and methylation was an operational reference standard rather than a true gold standard, risking selection and verification bias; no confidence intervals are reported.

Study Type: Retrospective single-cohort study (n=153)

Key Question: Is continuous intraoperative dorsal cochlear nucleus action potential (DNAP) monitoring via a depth electrode safe and better than standard ABR at predicting hearing outcomes in retrosigmoid vestibular schwannoma surgery?

Key Findings:

• Stable baseline signal was obtained in 80.4% (123/153) with DNAP versus 60.8% (93/153) with ABR; no complications were attributed to the electrode.
• Serviceable hearing (AAO-HNS A/B) was achieved in 41.2% and WRS ≥50% in 56.2% at 5-7 days, with similar rates at 6 months (137 with audiometry).
• DNAP preservation was the most consistent independent predictor of outcome; an optimal residual amplitude ratio cutoff of 0.41 was identified, with higher sensitivity than ABR (specific values not given in the abstract).

Clinical Relevance: DNAP monitoring may give more reliable, near real-time feedback than ABR during hearing-preservation surgery, though its availability and role in UK practice remain to be established.

Limitations: Retrospective, single-cohort design with no external validation of the 0.41 cutoff, which was derived from the same dataset it was tested on.