Study of EEG and Nasal Stimulus in Olfactory Disorders

Official title

Neuroscent: EEG Analysis of Cortical Signals Induced by Olfactory Stimuli in Normosmic Subjects and Individuals With Olfactory Disorders, With an In-depth Study of Olfactory Pathways in Patients With Tinnitus

Overview

Neuroscent aims to analyze EEG signals induced by olfactory stimuli in individuals with normal and impaired olfactory functions, with a focus on patients with tinnitus. The study seeks to develop reliable diagnostic methods using EEG to differentiate between normosmic and hyposmic subjects during olfactory tests, potentially enhancing our understanding of the brain's response to olfactory stimuli. This 24-month interventional study with a device to be patented will involve 1000 participants and aims to establish more effective diagnostic and therapeutic tools for olfactory disorders

Detailed description

The Neuroscent project investigates the EEG signals elicited by olfactory stimuli in both normosmic individuals and those with olfactory disorders, with a focus on tinnitus patients. The primary objective is to utilize EEG analysis to identify and quantify brain wave responses during olfactory tests with Sniffin' Sticks, aiming to accurately differentiate between normosmic and hyposmic subjects. This research aims to enhance the diagnostic precision and understanding of the interplay between olfactory and auditory stimuli in the brain. The 24-month, interventional study with a device to be patented, co-financed by the Ministry of Health and Ministry of the Interior under the PNRR 2023, will recruit 1000 participants divided into four groups: normosmics (550), hyposmics (150), tinnitus patients with hyposmia (150), and tinnitus patients without hyposmia (150). Participants will undergo comprehensive olfactory assessments, including the Sniffin' Sticks test, and EEG recordings will be taken during olfactory stimulation to capture brain wave patterns. Advanced data analysis techniques, such as Random Forest algorithms and t-SNE dimensionality reduction, will be employed to classify and interpret the EEG signals, aiming to develop effective diagnostic and therapeutic tools for olfactory disorders, thereby improving clinical outcomes and quality of life for affected individuals.

Interventions

• Diagnostic test Sniffin'Sticks
  The Sniffin' Sticks test, a validated method to evaluate olfactory functions, utilizes pen-like devices to dispense scents for testing identification, discrimination, and detection of odors. In this study, participants' responses to various scents are recorded. EEG (Electroencephalography) captures electrical activity in the brain during exposure to these odors by using an EEG cap fitted with electrodes on the scalp. This allows for the monitoring of brain wave patterns in response to olfactory

Primary outcome measures

• Enrollment and data collection [Time frame: 22 months]
• EEG Parameters (in µV²) [Time frame: 22 months]
• Behavioral/Performance Measures (Scores) [Time frame: 22 months]
• Model Performance Metrics (Accuracy) [Time frame: 22 months]
• Dimensionality Change Outputs (t-SNE) [Time frame: 22 months]

Secondary outcome measures (7)

• Pure Tone Audiometry Test [Time frame: 22 months (Simultaneously with the primary outcome)]
• Behavioral/Performance Measures (Scores) [Time frame: 22 months (Simultaneously with the primary outcome)]
• EEG Parameters [Time frame: 22 months (Simultaneously with the primary outcome)]
• Model Performance Metrics [Time frame: 22 months (Simultaneously with the primary outcome)]
• Power Analysis and Post-hoc Analyses [Time frame: 22 months (Simultaneously with the primary outcome)]
• Auditory Brainstem Response (ABR) [Time frame: 22 months (Simultaneously with the primary outcome)]
• Tympanometry [Time frame: 22 months (Simultaneously with the primary outcome)]

Eligibility criteria

Inclusion criteria

• Subjects over 18 years of age who have given consent for the collection of specified data, including medical history and personal information, for the purposes of project implementation and in accordance with the ethical standards of the institutions where the project will be conducted.

Exclusion criteria

• Previous fractures of the facial bones, particularly the ethmoid bone.
• Active tumors of the brain or face, including tumors of the nose, paranasal sinuses, oral cavity, or nasopharynx.
• Active nasal-sinus conditions, particularly radiologically proven sinusitis.
• Mass in the pontocerebellar angle, especially schwannoma of the VIII nerve.
• Patients with acute and chronic inflammatory diseases of the middle ear, otosclerosis, inner ear diseases (especially Meniere's disease), objective tinnitus, and tinnitus caused by middle ear pathologies and CPA tumors.
• Neurodegenerative diseases (especially Alzheimer's and Parkinson's disease).
• Known history of neuropsychiatric or cerebral disorders.
• Use of psychotropic drugs or drugs active on the central nervous system.
• Alcohol and drug abuse.

Criteria are shown verbatim from the registry (in English). Final eligibility is always assessed by the study center.

Healthy volunteers: Yes

Study design

Allocation

Non-randomized

Model

Parallel assignment

Masking

Open label

Primary purpose

Diagnostic

Study locations

Center list to be confirmed — check the primary protocol.

Identifiers

NCT: NCT06589375 · ID6911

Primary sources (government registries)

• ClinicalTrials.gov (US NIH)

View this study on ClinicalTrials.gov ↗