The Efficacy of Modified Olfactory Training Method for Patients With Post-viral Olfactory Dysfunction
Trial statusRecruiting
Trial phaseNot applicable
Trial typeInterventional
Biological sexAll
Age18-80
SponsorPeking University Third Hospital
About this trial
The goal of this clinical trial is to validate the effectiveness of the modified olfactory training device, the main questions it aims to answer are: Is the modified olfactory training device effective in treating patients with post-viral olfactory dysfunction? Compared to the conventional device, how efficient is the modified olfactory training device for improving olfactory function?
Eligibility criteria
This trial does not accept healthy volunteersQualifiers
Age 18-80 years old, gender not limited.
Patients diagnosed with olfactory dysfunction following infections of the upper respiratory tract, as determined by Sniffin' Sticks test (including TDI value test).
Voluntarily signs the informed consent form.
Disqualifiers
Patients with post-traumatic olfactory dysfunction, rhinosinusitis-related dysfunction and olfactory dysfunction caused by other reasons.
Patients with concomitant sinonasal disease.
Patients with chronic diseases, such as hypertension, diabetes, bronchopneumonia, chronic obstructive pulmonary disease, etc.
Patients with serious coexisting diseases: such as malignant tumors, etc., with a life expectancy of less than 2 years.
Trial design
Design model
Parallel
Treatments tested in this trial
Conventional olfactory training device
DeviceConventional olfactory training was designed by Hummel et al. They performed OT using four odors (phenyl ethyl alcohol, rose; eucalyptol, eucalyptus; citronella, lemon; and eugenol, cloves), which are representative of four odor categories on the odor prism proposed by Henning.
Modified olfactory training device
DeviceParticipants will use a modified olfactory training device based on expiratory pressure. Its bidirectional airflow and unidirectional pressure characteristics significantly increased the deposition rate of olfactory odors in the olfactory cleft area, making the patient feel stronger in the nasal cavity during olfactory training.
Conventional olfactory training device with placebo
DeviceBased on the traditional olfactory training device, four olfactory odors are replaced by placebo。
Treatment groups
150 Participants
are divided into 3 treatment groupsGroup A: The Conventional olfactory trainingActive comparator 1 intervention
Group B: The Control groupSham comparator 1 intervention
Group C: The Modified olfactory trainingExperimental treatment 1 intervention
Trial outcomes
Primary outcomes
1
The total scores in the "Sniffin 'Sticks" test
This olfactory test consists of three subtests that respectively measure odor threshold (T), odor discrimination (D), and odor identification (I). Each subtest has a maximum score of 16, and the sum of the scores from the three subtests provides the global olfactory score (TDI score; Threshold, Discrimination, Identification) with a maximum of 48 points. Patients with a TDI composite score≥30.5 are defined as normosmic. In contrast, those with a TDI composite score between 16.5 and 30.5 are defined as hyposmic, and patients with a TDI composite score\<16.5 are defined as functionally anosmic. Based on previous literature, we have established a 5.5 points improvement in the TDI composite score as a significant change.
Time frame
Baseline,Month 3,Month 6,Month 12,Month 24Secondary outcomes
1
OB volume and shape measurement
OB volumetric evaluations will be performed with a 3-Tesla MRI system with coronal T2-weighted fast spin-echo images that included the anterior and the middle parts of the skull base. The OB volume will be measured using manual segmentation. The contours of the left and the right OBs will be manually delineated. The proximal limit of the OB will be determined on the basis of the sudden change in the diameter at the beginning of the olfactory tract. After all surfaces are added and multiplied by the slice thickness, the volume in cubic millimeters will be obtained for the right and the left OBs, and the total OB volume will be calculated as the sum of the two values. Measurements will be performed blindly twice by two examiners. When the difference in volume is \> 10%, the examiners will perform a third measurement together. We have interpreted oval, round, triangular, and bean/boat/banana shapes as normal variants of OB shape.Atrophy will be interpreted as flattened OB.
Time frame
Baseline,Month 3,Month 6,Month 12,Month 242
MRI volumetric evaluation related to GM
Magnetic resonance imaging (MRI) scans will be performed on a 3T Siemens Verio scanner with a 12-channel phased-array head coil,measuring gray matter(GM) volumes to explore the connection between olfactory function and brain regions.
Time frame
Baseline,Month 3,Month 6,Month 12,Month 243
MRI volumetric evaluation related to WM
Magnetic resonance imaging (MRI) scans will be performed on a 3T Siemens Verio scanner with a 12-channel phased-array head coil,measuring white matter(WM) volumes to explore the connection between olfactory function and brain regions.
Time frame
Baseline,Month 3,Month 6,Month 12,Month 244
MRI volumetric evaluation related to CSF
Magnetic resonance imaging (MRI) scans will be performed on a 3T Siemens Verio scanner with a 12-channel phased-array head coil,measuring cerebrospinal fluid(CSF) volumes to explore the connection between olfactory function and brain regions.
Time frame
Baseline,Month 3,Month 6,Month 12,Month 24Sponsors and contacts
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Source ClinicalTrials.gov