Sudden sensorineural olfactory loss: a structured narrative review and proposal for a standardised terminological...

Area of Science:

• Neurology
• Otolaryngology
• Medical Terminology

Background:

• Sudden sensorineural olfactory loss is a clinically significant condition lacking standardized nomenclature, diagnostic codes, and treatment guidelines.
• This deficit leads to diagnostic delays, inconsistent research reporting, and difficulties in synthesizing scientific evidence.
• The COVID-19 pandemic highlighted the inadequacy of current frameworks for addressing widespread olfactory dysfunction.

Purpose of the Study:

• To review the evidence on sudden sensorineural olfactory loss.
• To demonstrate the inadequacy of existing terminology for this condition.
• To propose a single, unified clinical term: Sudden Sensorineural Olfactory Loss (SSNOL).

Main Methods:

• A structured narrative review of studies published between 2000 and 2024.
• Databases searched included PubMed, Embase, and Scopus.
• Selection criteria focused on sudden olfactory dysfunction, neural mechanisms, diagnostics, and clinical management.

Main Results:

• Sudden sensorineural olfactory loss can lead to severe and permanent neural consequences.
• Current diagnostic tools and treatments are limited, with olfactory training being the only intervention with consistent evidence.
• The lack of standardized terminology hinders research synthesis and clinical response.

Conclusions:

• The term Sudden Sensorineural Olfactory Loss (SSNOL) is proposed, modeled after Sudden Sensorineural Hearing Loss (SSNHL).
• Two descriptive etiological categories, SSNOL-Viral and SSNOL-Idiopathic, are suggested for future research.
• Traumatic olfactory loss is excluded from the SSNOL definition and will be managed separately.