Arnold Chiari Malformation: the Otological Assessment as an Objective Criteria for Surgical Treatment

Study Overview
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Brief Summary
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The aim of this study is to compare the value of multifrequency tympanometry between patients with surgical indication of treatment for a Chiari type I malformation and healthy volunteers.

Detailed Description
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Prevalence of Chiari type I malformation in population is between 0.1% and 0.5%. Chiari type I malformation is responsive in perturbation of the cerebro spinal fluid flow at the cranio-cervical junction. Those perturbations caused headaches, and various otological symptoms (dizziness, tinnitus, vertigo, nystagmus, hypoacousis…). The surgical treatment consists in an occipital craniotomy to restore the cerebro spinal fluid flow at the cranio-cervical junction. Symptoms are due to increasing of the pressure in the cerebellar fossa. 81% of the patients with Chiari type 1 malformation suffer of sub clinical otological perturbations especially alteration of the vestibular test. In the literature, hearing performance could be normalized after posterior fossa decompression. Furthermore, the multifrequency tympanometry measurement and particularly the width of conductance tympanograms at 2 kHz shows that variations of the cerebro spinal fluid pressure have consequences on the pressure of the perilymph. Investigator's hypothesis is that tympanometry (conductance) could be an effective test to show the variation of the cerebro spinal fluid pressure.

Official Title
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Arnold Chiari Malformation: the Otological Assessment as an Objective Criteria for Surgical Treatment

Conditions
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Arnold-Chiari Malformation, Type 1

Intervention / Treatment
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* Diagnostic Test: Multifrequency tympanometry at Inclusion
* Diagnostic Test: Multifrequency tympanometry 6 month after surgery


Participation Criteria
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Eligibility Criteria
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Inclusion criteria: Chiari type I malformation proved at MRI or CT-scan with an indication of cranio cervical decompression. Patients between 18 and 60 years old. Patient should benefit of the national health care system Agreement of the patient Inclusion criteria for healthy volunteers: Between 18 and 60 years old. Free of otologic pathology Benefit of the national health care system Agreement of the volunteers Exclusion criteria: Acute hydrocephaly Other type of Chiari disease (induced…) Medical history of neurosurgery Contraindication for MRI Cophosis Chronic otitis Medical history of ontological surgery Tympanic perforation Disturbance of tonal audiometry with air bone more than 20dB in 4 frequencies with abolition of stapedial reflex Pregnant women or nursing women Protected adults by French laws Exclusion criteria for healthy volunteers: Medical history of neurosurgery Cophosis Chronic otitis Medical history of ontological surgery Tympanic perforation Disturbance of tonal audiometry with air bone more than 20dB in 4 frequencies with abolition of stapedial reflex Pregnant women or nursing women Medical history of Chiari malformation Chronic headaches or neck pain Protected adults by French laws

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 60 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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Accepts Healthy Volunteers

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Diagnostic
Allocation: Non-Randomized
Intervention Model: Parallel Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Patients with Chiari type 1 malformation<br>Tympanometry measurement at inclusion and 6 months after surgery | Diagnostic Test: Multifrequency tympanometry at Inclusion<br>* Multifrequency tympanometry measurement and particularly width of conductance tympanograms at 2 kHz will be performed for both group at inclusion<br>Diagnostic Test: Multifrequency tympanometry 6 month after surgery<br>* Multifrequency tympanometry measurement and particularly width of conductance tympanograms at 2 kHz will be performed 6 months after surgery for Chiari type I malformation patient<br>|
| Experimental: Healthy volunteers<br>Tympanometry measurement at inclusion. Every healthy volunteer will be match with a patient for his age and his BMI (body mass index). | Diagnostic Test: Multifrequency tympanometry at Inclusion<br>* Multifrequency tympanometry measurement and particularly width of conductance tympanograms at 2 kHz will be performed for both group at inclusion<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Width of conductance tympanograms at 2 kHz measurement |  | Inclusion | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Multifrequency tympanometry |  | Inclusion and 6 months after surgery for patients with an indication of surgical management for a Chiari type I malformation | 
| Resonance frequency |  | Inclusion and 6 months after surgery for patients with an indication of surgical management for a Chiari type I malformation | 
| Audiometric parameters |  | Inclusion and 6 months after surgery for patients with an indication of surgical management for a Chiari type I malformation | 
| Otological symptoms |  | Inclusion and 6 months after surgery for patients with an indication of surgical management for a Chiari type I malformation | 
| Pain measurement with Headache Impact Test |  | Inclusion and 6 months after surgery for patients with an indication of surgical management for a Chiari type I malformation | 
| Cerebro spinal fluid pressure of the cranio cervical junction |  | Inclusion and 6 months after surgery for patients with an indication of surgical management for a Chiari type I malformation | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Arnold-Chiari Malformation, Type 1, Multifrequency tympanometry, Inner ear pressure