Diagnostic accuracy of spirometry, CT, and virtual bronchoscopy for laryngotracheal stenosis: a meta-analysis and evidence-based pathway

Abstract Background Diagnostic delays in laryngotracheal stenosis (LTS) are common due to non-specific symptoms and reliance on invasive laryngotracheobronchoscopy (LTB). The comparative accuracy and optimal clinical roles of non-invasive alternatives—spirometry, computed tomography (CT), and CT virtual bronchoscopy (CTVB)—remain undefined, particularly for resource-limited settings. Methods This diagnostic meta-analysis was conducted according to a pre-registered protocol (PROSPERO CRD420251044416) and followed PRISMA-DTA guidelines. Data from 14 studies (30 evaluations) were pooled to compare the accuracy of spirometry, CT, and CTVB for diagnosing adolescent/adult LTS, using LTB as the reference standard. Pooled sensitivity, specificity, likelihood ratios, and diagnostic odds ratios were calculated using bivariate random-effects models. Meta-regression explored heterogeneity sources (PROGRESS-Plus framework), and the GRADE-Equity approach assessed evidence certainty. Results CTVB demonstrated the highest sensitivity (93·7%, 95% CI: 90·8–95·9) and optimal rule-out capacity (NLR 0·14). CT showed the highest specificity (97·1%, 94·9–98·5) and rule-in utility (PLR 9·7). Spirometry offered balanced accuracy (sensitivity 91·3%; specificity 90·1%) but with significant heterogeneity; its accuracy declined with increasing patient age (p < 0·05). Meta-regression identified key modifiers: retrospective design reduced CT sensitivity, and site-based (vs. diameter) CTVB measurement reduced specificity. Equity analysis revealed high-risk groups, including older adults for spirometry and populations in resource-limited settings for CT. Conclusions This analysis defines the complementary roles of CTVB and CT as the optimal non-invasive screening-confirmation duo for LTS. The proposed CTVB→CT diagnostic pathway can fundamentally shift the diagnostic paradigm, reducing the need for invasive endoscopy as a first-line test. Implementation of this strategy, particularly with standardized CTVB measurements and age-adjusted spirometry thresholds, can mitigate diagnostic delays and improve equity in patient care globally.