A recent Neurosurgery digest,
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Study Type: Retrospective cohort study

Key Question: Does pregnancy or vaginal delivery affect shunt function or disease recurrence in women with idiopathic intracranial hypertension (IIH) previously treated with VP shunting?

Key Findings:

• Among 61 shunted IIH patients, 9 women had 12 pregnancies (live births) at a median of 40.5 months post-shunting; 9/12 deliveries were vaginal, with no shunt adjustment, infection, or malfunction.
• IIH onset was unrelated to pregnancy in all but one case; that patient developed refractory visual loss in the first trimester, managed successfully with VP shunting at 11 weeks' gestation followed by elective Caesarean section.

Clinical Relevance: Provides reassurance for UK neurosurgical and obstetric teams that pregnancy and vaginal delivery are generally safe in women with programmable/gravitational VP shunts for IIH, supporting multidisciplinary, individualised management rather than routine Caesarean or shunt revision.

Limitations: Small sample size (9 women, 12 pregnancies) from a single centre limits generalisability and statistical power.

Study Type: Cadaveric anatomical study with illustrative surgical case review

Key Question: What is the detailed microsurgical anatomy of the posterior cavernous sinus compartment relevant to safe endoscopic endonasal resection of invasive pituitary adenomas?

Key Findings:

• Posterior compartment shape was triangular in 66.7% and quadrilateral in 33.3% of hemispheres, determined by ICA posterior genu angulation.
• Posterior parasellar ligament identified in 64% (42% two-anchor, 58% net-like); Gruber's ligament seen as a robust band in 78% (59% ossified), forming potential corridors for tumour invasion/residual disease.
• Four consistent venous outlets (basilar, foramen lacerum, inferior and superior petrosal plexuses) were mapped as key landmarks.

Clinical Relevance: Provides UK skull-base neurosurgeons with anatomical landmarks and ligamentous/venous corridors to improve safety and completeness of EEA resection for invasive pituitary adenomas extending into the posterior cavernous sinus.

Limitations: Findings are based on cadaveric dissection, which may not fully replicate tumour-distorted anatomy or intraoperative variability seen in vivo.

Study Type: Modelling study (discrete-time Markov pipeline simulation with Monte Carlo uncertainty analysis)

Key Question: How will the African neurosurgical workforce evolve by 2030 under different policy scenarios, and what infrastructure/training constraints limit subspecialisation?

Key Findings:

• Baseline projection: workforce grows from a median of 10 neurosurgeons/country to 5888 by 2030 (+43.1%); a policy pack (scholarships, mentorship, equipment) increases this to 8809 (+49.6% over baseline).
• Training bottlenecks are severe: ~231 interested medical students annually vs. limited residency capacity, with waiting lists growing by ~154 applicants/year.
• Equipment readiness varies extremely (only Egypt scores 0.81; 21 countries <0.10), limiting subspecialisation; policy pack significantly raised projected female workforce share (OR 1.28, 95% CI 1.01–1.61, p=0.04).

Clinical Relevance: Highlights systemic training and infrastructure bottlenecks relevant to UK-Africa neurosurgical partnerships, fellowship programmes, and global health engagement/workforce planning initiatives.

Limitations: Findings rely on modelled projections and survey-derived inputs with inherent uncertainty, rather than direct empirical workforce tracking.

Study Type: Historical/biographical commentary (not original clinical research)

Key Question: What were Eugène-Louis Doyen's contributions to the early development of neurosurgical technique, particularly for trigeminal neuralgia?

Key Findings:

• Doyen combined the Hartley-Krause subtemporal and Rose sphenoidal routes to develop a refined trigeminal ganglionectomy technique aimed at reducing complications.
• He innovated surgical instrumentation, including an electric craniotome, dural detachment tools, and devices enabling en bloc ganglion resection.
• He pioneered a minimally invasive retrosigmoid approach using a speculum and custom neurotome to divide the trigeminal sensory root, prefiguring modern cerebellopontine angle endoscopic techniques.

Clinical Relevance: Provides historical context for the evolution of skull base and trigeminal neuralgia surgery, illustrating the technical lineage underpinning contemporary retrosigmoid and endoscopic approaches used in UK neurosurgical practice.

Limitations: As a historical narrative review, it lacks primary clinical data or outcome analysis to substantiate efficacy claims.

Study Type: Retrospective multicenter cohort study

Key Question: Can a standardised voxel-based mapping system (Brain-Grid) quantify glioblastoma location and invasiveness to improve prognostic stratification?

Key Findings:

• Greater tumor infiltration (≥6 BG voxels) was associated with shorter OS (p=0.012); mean OS was 14.4±8.86 months across 116 patients.
• Tumors most frequently involved basal ganglia/subventricular zone voxels; posterior tumor location predicted better survival (AUC 0.71), and resection involving voxel A2-C2-S3 correlated with improved OS (p=0.03).
• Higher pre-/postoperative tumor volume and lower extent of resection independently predicted worse survival (p=0.012, 0.001, 0.002); MGMT methylation showed no survival or spatial correlation (p=0.15).

Clinical Relevance: Offers UK neurosurgical teams a reproducible, voxel-based framework to integrate tumor topography and infiltration extent into preoperative MDT planning and prognostic counselling, complementing molecular data.

Limitations: Retrospective design with modest sample size limits causal inference and generalisability of voxel-based cutoffs.

Study Type: Retrospective cohort study (National Trauma Data Bank, 2023)

Key Question: Does trauma center level (I vs II) influence in-hospital mortality after operative spine trauma, and does this vary by whether patients are directly admitted or transferred?

Key Findings:

• Among 12,516 operative spine trauma patients, direct admission to a level I centre was associated with significantly lower adjusted mortality odds versus level II (aOR 0.62, 95% CI 0.39–0.97, p=0.037).
• No mortality benefit was seen for interfacility transfers to level I centres (aOR 0.88, 95% CI 0.47–1.68, p=0.693).
• Level I centres treated more severely injured and comorbid patients, and received a disproportionate share of transfers.

Clinical Relevance: Supports prioritising direct prehospital transport to major trauma centres for spine trauma patients within UK trauma networks, as delayed transfer may negate survival benefits of specialist care.

Limitations: Retrospective registry data cannot fully capture prehospital timing, transfer delays, or unmeasured confounders influencing triage decisions.

Study Type: Retrospective cohort study (propensity-matched, multicenter database analysis)

Key Question: Does postoperative ketorolac use increase pseudarthrosis risk following anterior lumbar interbody fusion (ALIF)?

Key Findings:

• Among 2408 matched patients per cohort, ketorolac was associated with a *lower* pseudarthrosis rate at 2 years (3.99% vs 5.44%; RR 0.733, 95% CI 0.567–0.948, p=0.017), not increased risk.
• No significant difference in reoperation rate (4.82% vs 5.31%; RR 0.906, p=0.430) or postoperative opioid use (21.7% vs 21.8%; p=0.972).
• No difference in 90-day complications (bleeding, hematoma/seroma, infection, ileus)—none occurred in either group.

Clinical Relevance: Supports safe use of short-course postoperative NSAIDs as opioid-sparing analgesia after ALIF, relevant to NHS enhanced recovery and opioid-reduction pathways in spinal surgery.

Limitations: Retrospective database design relies on coding accuracy and lacks granular data on ketorolac dose/duration, limiting causal inference.

Study Type: Prospective multicentre cohort study (registry-based, Quality Outcomes Database)

Key Question: Do patient-reported outcomes after MIS versus open surgery for grade 1 lumbar spondylolisthesis diverge over 5-year follow-up?

Key Findings:

• No difference in ODI, EQ-5D, or pain scores between MIS and open surgery at 3 and 12 months.
• By 24 and 60 months, MIS showed greater ODI improvement (e.g., -25.8 vs -20.9 at 24 months, p=0.0116) and higher MCID achievement (72.8% vs 61.1% at 24 months, p=0.009); effect persisted on multivariable analysis (OR 1.6–2.0).
• Divergence was significant in arthrodesis patients but not in decompression-only subgroups; MIS also had less blood loss and shorter length of stay, with no difference in complications or reoperation.

Clinical Relevance: Supports considering MIS with fusion for long-term disability benefit in appropriately selected spondylolisthesis patients, relevant to NHS spinal units balancing resource use, training capacity, and patient selection for MIS pathways.

Limitations: Non-randomised registry design with baseline differences between groups (age, BMI, arthrodesis rate) introduces potential residual confounding despite multivariable adjustment.