Tinnitus

Introduction

Tinnitus is a common auditory symptom that presents significant challenges in diagnosis and management. This comprehensive guide is designed to help Canadian medical students prepare for the Medical Council of Canada Qualifying Examination Part I (MCCQE1), focusing on tinnitus within the context of Ear, Nose, and Throat (ENT) surgery.

Definition and Epidemiology

Tinnitus is defined as the perception of sound in the absence of an external acoustic stimulus. It's crucial for MCCQE1 candidates to understand its prevalence and impact in the Canadian population.

• Prevalence in Canada: Approximately 37% of adult Canadians report experiencing tinnitus, with about 7% describing it as severe enough to affect sleep or concentration.
• Demographics: More common in older adults, but can affect all age groups.
• Risk Factors: Noise exposure, age-related hearing loss, and certain occupations (e.g., musicians, industrial workers) are significant risk factors in the Canadian context.

Pathophysiology

Understanding the underlying mechanisms of tinnitus is essential for MCCQE1 preparation. The pathophysiology can be complex and multifactorial.

Classification

For MCCQE1 success, candidates should be familiar with the classification of tinnitus:

1. Subjective Tinnitus

   • Heard only by the patient
   • Most common form (95% of cases)

2. Objective Tinnitus

   • Can be heard by an examiner
   • Rare (5% of cases)
   • Often due to vascular or muscular causes

Etiology

A comprehensive understanding of tinnitus etiology is crucial for MCCQE1 preparation. Common causes include:

Clinical Presentation

MCCQE1 candidates should be well-versed in recognizing the clinical features of tinnitus:

• Sound Characteristics: Ringing, buzzing, hissing, or clicking
• Unilateral vs. Bilateral: Can affect one or both ears
• Continuous vs. Intermittent: May be constant or come and go
• Associated Symptoms: Hearing loss, vertigo, or balance problems
• Impact on Quality of Life: Sleep disturbances, concentration difficulties, anxiety, or depression

Diagnostic Approach

A systematic diagnostic approach is essential for MCCQE1 success:

1. Detailed History

   • Onset and duration of tinnitus
   • Characteristics of the sound
   • Associated symptoms
   • Exposure to loud noise
   • Medications
   • Impact on daily life

2. Physical Examination

   • Otoscopy
   • Cranial nerve examination
   • Auscultation for objective tinnitus

3. Audiological Assessment

   • Pure tone audiometry
   • Speech audiometry
   • Tympanometry

4. Imaging Studies (if indicated)

   • MRI of the internal auditory canal and cerebellopontine angle
   • CT scan of the temporal bone

5. Laboratory Tests (based on clinical suspicion)

   • Thyroid function tests
   • Lipid profile
   • Complete blood count
   • Vitamin B12 levels

Management

MCCQE1 candidates should be familiar with the multidisciplinary approach to tinnitus management in the Canadian healthcare context:

Conservative Management

1. Patient Education and Counseling

   • Explain the nature of tinnitus
   • Reassurance about benign nature (if appropriate)
   • Stress management techniques

2. Sound Therapy

   • Masking devices
   • White noise machines
   • Hearing aids (if hearing loss is present)

3. Cognitive Behavioral Therapy (CBT)

   • Widely available in Canadian healthcare settings
   • Helps patients cope with tinnitus-related distress

Pharmacological Management

• Antidepressants (e.g., nortriptyline)
• Anxiolytics (for short-term use)
• Melatonin (for sleep disturbances)

Specialized Treatments

• Tinnitus Retraining Therapy (TRT)

  • Combines counseling and sound therapy
  • Available in specialized clinics across Canada

• Transcranial Magnetic Stimulation (TMS)

  • Emerging treatment, available in some Canadian research centers

Canadian Guidelines

The Canadian Academy of Audiology (CAA) provides guidelines for tinnitus management:

1. Comprehensive audiological assessment is recommended for all patients with tinnitus.
2. A multidisciplinary approach involving ENT specialists, audiologists, and mental health professionals is encouraged.
3. Patient education and counseling should be the first-line intervention.
4. Sound therapy and CBT are recommended as primary management strategies.
5. Pharmacological interventions should be used judiciously and primarily for managing associated symptoms.

Key Points to Remember for MCCQE1

• Tinnitus affects a significant portion of the Canadian population, with higher prevalence in older adults.
• Subjective tinnitus is much more common than objective tinnitus.
• A thorough history and physical examination are crucial for diagnosis and management planning.
• No single treatment works for all patients; management should be individualized.
• Canadian guidelines emphasize a multidisciplinary approach and non-pharmacological interventions.
• Understanding the impact of tinnitus on quality of life is essential for patient-centered care (CanMEDS Communicator role).

Sample Question

# Sample Question

A 65-year-old man presents with a 6-month history of constant ringing in both ears. He reports difficulty sleeping and increased anxiety. His medical history includes hypertension and type 2 diabetes. Physical examination and audiometry reveal bilateral sensorineural hearing loss. Which of the following is the most appropriate initial management step?

- [ ] A. Prescribe amitriptyline
- [ ] B. Refer for MRI of the internal auditory canal
- [ ] C. Recommend cognitive behavioral therapy
- [ ] D. Start a trial of ginkgo biloba
- [ ] E. Prescribe hearing aids

Explanation

The correct answer is:

• C. Recommend cognitive behavioral therapy

Explanation: In this case, the patient presents with chronic bilateral tinnitus associated with sleep disturbances and anxiety. Given the bilateral nature and associated sensorineural hearing loss, this likely represents subjective tinnitus related to age-related hearing loss (presbycusis). According to Canadian guidelines, the initial management should focus on non-pharmacological interventions.

Cognitive Behavioral Therapy (CBT) is recommended as a first-line treatment for tinnitus, especially when it's affecting the patient's quality of life, as in this case with sleep disturbances and anxiety. CBT helps patients develop coping strategies and reduce tinnitus-related distress.

Let's review the other options:

A. Prescribing amitriptyline is not the first-line treatment. While it may be used in some cases, it's not recommended as an initial step.

B. MRI is not indicated as the initial step for bilateral tinnitus with a clear association with hearing loss, unless there are other neurological symptoms or signs.

D. Ginkgo biloba is not recommended by Canadian guidelines for tinnitus management due to lack of strong evidence.

E. While hearing aids may be beneficial, especially given the hearing loss, they are typically considered after initial management steps like CBT have been implemented.

This question tests the candidate's knowledge of appropriate initial management of tinnitus in the Canadian healthcare context, aligning with the CanMEDS roles of Medical Expert and Communicator.

References

1. Bhatt, J. M., Lin, H. W., & Bhattacharyya, N. (2016). Prevalence, Severity, Exposures, and Treatment Patterns of Tinnitus in the United States. JAMA Otolaryngology–Head & Neck Surgery, 142(10), 959. https://doi.org/10.1001/jamaoto.2016.1700 (opens in a new tab)

2. Tunkel, D. E., Bauer, C. A., Sun, G. H., Rosenfeld, R. M., Chandrasekhar, S. S., Cunningham, E. R., Archer, S. M., Blakley, B. W., Carter, J. M., Granieri, E. C., Henry, J. A., Hollingsworth, D., Khan, F. A., Mitchell, S., Monfared, A., Newman, C. W., Omole, F. S., Phillips, C. D., Robinson, S. K., … Whamond, E. J. (2014). Clinical Practice Guideline: Tinnitus. Otolaryngology–Head and Neck Surgery, 151(2_suppl), S1–S40. https://doi.org/10.1177/0194599814545325 (opens in a new tab)

3. Canadian Academy of Audiology. (2019). Tinnitus and Hyperacusis: Assessment and Management. Retrieved from https://canadianaudiology.ca/professional-resources/ (opens in a new tab)

4. Fuller, T. E., Haider, H. F., Kikidis, D., Lapira, A., Mazurek, B., Norena, A., Rabau, S., Lardinois, R., Cederroth, C. R., Edvall, N. K., Brueggemann, P. G., Rosing, S. N., Kapandais, A., Lungaard, D., Hoare, D. J., & Cima, R. F. F. (2017). Different Teams, Same Conclusions? A Systematic Review of Existing Clinical Guidelines for the Assessment and Treatment of Tinnitus in Adults. Frontiers in Psychology, 8. https://doi.org/10.3389/fpsyg.2017.00206 (opens in a new tab)

5. Henry, J. A., Roberts, L. E., Caspary, D. M., Theodoroff, S. M., & Salvi, R. J. (2014). Underlying Mechanisms of Tinnitus: Review and Clinical Implications. Journal of the American Academy of Audiology, 25(1), 5-22. https://doi.org/10.3766/jaaa.25.1.2 (opens in a new tab)