Can Olfactory Dysfunction Be Treated in ENT?
Yes, olfactory dysfunction can and should be treated in an ENT setting, as sinonasal-related smell loss is considered the most treatable form of olfactory dysfunction, though outcomes vary significantly by etiology and severity. 1
Diagnostic Approach in ENT
The ENT evaluation of olfactory dysfunction requires a systematic approach combining clinical examination with objective testing:
Rigid nasal endoscopy is essential to differentiate between conduction loss from sinonasal obstruction, inflammatory causes, and potential tumors that may explain smell decline 2, 3
Standardized psychophysical olfactory testing should be performed using validated instruments like UPSIT or Sniffin'Sticks, as patients are commonly not fully aware of their impairment or unable to estimate severity accurately 2, 4
Testing serves dual purposes: establishing baseline function and monitoring treatment outcomes following anti-inflammatory or surgical interventions 2, 4
When subjective symptoms and endoscopic findings don't correlate, imaging with MRI or CT should be pursued to exclude sinonasal or skull base tumors, olfactory bulb abnormalities, or pituitary lesions 2, 3
Treatment Modalities Available in ENT
Medical Management
Anti-inflammatory treatment can improve olfactory function in chronic rhinosinusitis (CRS) patients, though the EPOS 2020 guidelines note that monitoring with smell tests is recommended during follow-up 2
Olfactory training should be offered for post-infectious olfactory dysfunction, including COVID-19 cases, due to its simplicity, safety, and demonstrated effectiveness 3
Surgical Management
Endoscopic sinus surgery (ESS) significantly improves olfactory function in CRS patients with nasal polyposis (CRSwNP), with both objective UPSIT measurements and subjective VAS scores showing significant improvement 5
Patients with preoperative anosmia and nasal polyposis have the highest likelihood of olfactory improvement following ESS, though most remain with severe hyposmia despite improvement 6, 5
In CRS without nasal polyps (CRSsNP), surgical outcomes are less predictable, with one study showing no significant improvement in olfactory measurements 5
Historical data shows that ESS improved hyposmia and anosmia in 71% of patients with chronic sinusitis and nasal polyposis 7
Critical Clinical Considerations
Patient Selection
The presence of nasal polyposis is the strongest predictor of olfactory improvement following surgical intervention 6, 5
Mechanical blockage is only one pathophysiological factor causing olfactory loss in chronic sinusitis; inflammation affecting the olfactory epithelium plays a significant role 7, 1
Setting Realistic Expectations
Effects of treatment are usually transient and incomplete, even though sinonasal-related smell loss is the most treatable form of olfactory dysfunction 1
Most patients with anosmia who improve after surgery still have severe hyposmia, not complete recovery to normal function 6
Common Pitfalls to Avoid
Do not assume all olfactory complaints require imaging; most cases can be managed based on clinical examination and psychophysical testing alone 3
Avoid CT head or vascular imaging for olfactory evaluation, as these have no established role 3
Assessment before nasal surgery is important from a medico-legal standpoint to document baseline function 2
When to Refer Beyond ENT
Temporal lobe dysfunction should be assessed, as olfactory hallucinations (phantosmia) may indicate temporal lobe pathology, degenerative disease, or psychiatric conditions requiring neurological evaluation 3
Neurodegenerative disorders such as Alzheimer's, Parkinson's, and Lewy body dementia can cause central olfactory dysfunction and may require multidisciplinary management 3