The Neurosurgery Signal — Signal, Not Noise

Rapid review note

Journal Club is a rapid, AI-assisted appraisal layer. It highlights study design, effect estimates, and practice relevance, but it is still a briefing, not a replacement for the paper.

For education only. Not medical advice.

Paper snapshot

Rapid study overview

Open paper

DOI

10.1097/MAO.0000000000004404

PMID

N/A

PICO

Population

Adults aged 18 years or older with small sporadic vestibular schwannoma of 15 mm or less who underwent hearing-preservation microsurgery at one tertiary academic center; prior surgery, radiation, meningioma, and NF2 were excluded.

Intervention

Microsurgical resection through a middle cranial fossa or retrosigmoid approach by the same neurotology-neurosurgery team with intraoperative facial EMG and auditory brainstem response monitoring.

Comparator

Within-cohort prognostic comparisons, especially tumors 10 mm or smaller versus 10.1 to 15 mm and patients with versus without preoperative vertigo.

Outcomes

Postoperative hearing preservation defined as word recognition score of at least 50%, facial nerve function, audiometric change, and extent of resection.

Design

Type

Retrospective single-center consecutive cohort

Randomized

Multicenter

Blinded

N/A

Follow-up

Audiogram at about 4 weeks; facial nerve at last follow-up

Primary endpoint

Postoperative hearing preservation defined as a word recognition score of at least 50%.

Secondary endpoints

House-Brackmann facial nerve function at last follow-up
Change in pure-tone average and word recognition score
Clinical and tumor predictors of hearing preservation

Practice impact

What this means

This consecutive 230-patient vestibular schwannoma microsurgery series says that hearing-preservation surgery can work well in experienced hands, but timing matters. Overall hearing preservation was 61%, it rose to 72% when tumors were 10 mm or smaller, and facial nerve outcomes remained excellent. The result is useful for counseling patients already leaning toward surgery, but it does not compare surgery with observation or radiosurgery.

Bottom line

For patients who already favor microsurgical hearing-preservation treatment of a small sporadic vestibular schwannoma, counseling should emphasize that outcomes were best when tumors were 10 mm or smaller.

Strength of evidence

low

Recommendation

consider change

Why it matters

Hearing preservation was 72% for tumors 10 mm or smaller versus 48% above 10 mm in this consecutive series.
Facial nerve outcomes were excellent, with House-Brackmann grade 1 or 2 in 95% of patients.
Confidence is still limited because this was a retrospective single-center cohort without a nonsurgical comparator.

What would change my mind

A prospective multicenter study confirming the same tumor-size gradient for hearing preservation across different skull base teams.
Comparative data showing that earlier microsurgery for 10 mm or smaller tumors preserves hearing better than observation or radiosurgery in similar patients.

Critical appraisal

How strong is the paper?

Methods critique

Risk of bias

This was a single-center retrospective surgical series of patients who elected microsurgery, so referral patterns and treatment preference create substantial selection bias.

Confounding

Surgical approach was chosen by age, tumor anatomy, and fundal extension rather than randomized, and the same tumor-size factors that guided approach also predicted hearing outcome.

Missing data

Two of 230 patients did not complete postoperative audiography and were excluded from final hearing analysis, and the authors acknowledge limited long-term audiometric follow-up.

Multiplicity

Many candidate predictors were screened in univariate logistic regression before multivariable modeling, with no reported correction for multiple testing.

Notes

Using the same neurotology-neurosurgery team likely reduced technical variability but may limit generalizability.
The study offered hearing-preservation surgery even to some patients with class D hearing who strongly desired any retained hearing.

Stats check

NNT

N/A

Effect sizes

Preoperative vertigo was associated with lower odds of hearing preservation (OR 0.33, 95% CI 0.17-0.62; p<0.001).
Tumor size 0-5 mm and 5.1-10 mm were associated with higher odds of hearing preservation than tumors larger than 10 mm (OR 3.62, 95% CI 1.39-9.4; and OR 2.52, 95% CI 1.30-4.9).
Middle fossa surgery showed only a nonsignificant trend toward better hearing preservation than retrosigmoid surgery (OR 1.95, 95% CI 0.98-3.88; p=0.06).

Absolute effects

Hearing was preserved in 61% of analyzed patients (139 of 228).
Hearing preservation was 72% for tumors 10 mm or smaller versus 48% for tumors larger than 10 mm.
House-Brackmann grade 1 or 2 facial function was maintained in 95% of patients (218 of 230), and gross-total resection was achieved in 98% (226 of 230).

Concerns

There was no observation or radiosurgery comparator, so the study supports prognostic counseling within microsurgery rather than comparative effectiveness.
The main hearing outcome was based on early postoperative audiography obtained on average within 4 weeks, which may not reflect long-term durability.
The regression model identifies associations, but it does not prove that operating earlier causes better hearing preservation.

External validity

Who it applies to

Adults with small sporadic vestibular schwannoma considering hearing-preservation microsurgery at experienced skull base centers.

Who it does not

Patients with NF2, prior radiation or surgery, tumors larger than 15 mm, or centers without comparable microsurgical and neurophysiology expertise.

Generalizability notes

Eighty-two percent of patients underwent the middle cranial fossa approach, reflecting this center's selection pattern.
Results came from one high-volume tertiary team, so performance may be less favorable in lower-volume programs.
The paper is most useful for microsurgical counseling and not for choosing microsurgery over observation or radiosurgery.

Evidence trace

Source trace and metadata

Citations (13)

claim_id

methods_critique.risk_of_bias

locator

p. 1; p. 2

claim_id

methods_critique.confounding

locator

p. 2; p. 4 Table 4

claim_id

methods_critique.missing_data

locator

p. 2; p. 5

claim_id

methods_critique.multiplicity

locator

p. 2; p. 4 Table 3; p. 4 Table 4

claim_id

methods_critique.notes

locator

p. 2; p. 5

claim_id

stats_check.effect_sizes

locator

p. 4 Table 4

claim_id

stats_check.absolute_effects

locator

p. 2; p. 3 Table 2

claim_id

stats_check.nnt

locator

p. 2; p. 4 Table 4

claim_id

stats_check.concerns

locator

p. 2; p. 5

claim_id

practice_impact.bottom_line

locator

p. 4; p. 5

quote

proactive early intervention when tumors are less than 10 mm merits consideration

claim_id

practice_impact.strength_of_evidence

locator

p. 5

claim_id

practice_impact.recommendation

locator

p. 4; p. 5

claim_id

practice_impact.rationale

locator

p. 2; p. 3; p. 5

Metadata

Generated at

2026-03-08T20:55:00Z

Version

manual-pdf-repair-v1