Sudden sensorineural hearing loss: mechanistic insights, therapeutic controversies, and a future blueprint toward precision medicine

Sudden sensorineural hearing loss (SSNHL) represents a complex otological emergency, historically managed through empiric strategies centered on systemic glucocorticoids. The diagnostic and therapeutic paradigm, however, is undergoing a fundamental shift from this one-size-fits-all approach toward mechanism-based precision medicine. This narrative review critically synthesizes and evaluates the latest evidence up to 2025 to chart this evolution. Etiologically, we transcend traditional parallel hypotheses (viral, vascular, immune) by proposing an integrated pathophysiological model centered on the possible dysfunction of the inner ear's neurovascular unit (NVU). We critically compare this model against classical frameworks, demonstrating how it may reconcile clinical observations of concurrent inflammation and vascular risk factors. We further employ insights from Mendelian randomization studies to critically re-evaluate the causal role of traditional risk factors. Diagnostically, we detail the transition from a mere “diagnosis of exclusion” to the ambitious goal of early biological subtyping, driven by multimodal data fusion. We propose a tiered diagnostic strategy, differentiating clinically ready tools from research-grade modalities. Therapeutically, we provide a granular analysis of core controversies, analyzed through an evidence hierarchy: the “triangular controversy” of glucocorticoid administration, the specific niche for salvage therapies like hyperbaric oxygen, and a pragmatic evaluation of adjuvant drugs. We present a risk-stratified, actionable treatment pathway that identifies candidates for initial combination therapy. We evaluate the emerging rationale for this approach and critically assess the translational gap facing regenerative medicine. Finally, we construct a forward-looking blueprint that draws lessons from other disciplines, advocates for building dynamic prognostic models, and implements a patient-centered, full-cycle management ecosystem that extends beyond acute hearing recovery to encompass rehabilitation, tinnitus management, and psychological support. This review concludes by framing the NVU dysfunction model as a hypothesis-generating framework and proposing a risk-stratified, cost-conscious precision treatment pathway, positioning SSNHL management as an integrated, lifelong health concern. Future research must bridge evidence gaps through rigorously designed, cross-disciplinary adaptive clinical trials and systems biology‑driven discovery of actionable biological subtypes, ultimately transforming SSNHL management into a proactive, preventive, and personalized paradigm.