Detailed Diagnostic Tests Performed by Specialist Audiologists

VNG (Videonystagmography) Test Battery, The VNG test battery consists of a series of tests used to evaluate the balance functions of the inner ear and central nervous system. The main tests included in the VNG test battery are as follows:

Tests Used to Evaluate Balance

1. Gaze Test: This test assesses the ability of the eyes to focus on a specific point and determines whether there is any deviation from it. It helps identify the presence of nystagmus (involuntary eye movements).

2. Spontaneous Nystagmus Test: This test evaluates whether there are involuntary, rhythmic oscillations (nystagmus) in the patient’s eye movements. It is conducted while observing the patient’s eyes in a free-gaze state, without focusing on any target.

To evaluate eye movements more precisely, the test may be conducted in a dark room with a light directed at the eyes or recorded using special video goggles (Videonystagmography – VNG).

3. Smooth Pursuit Test: Evaluates the ability of the eyes to track a slowly moving object. Central nervous system disorders can affect this test.

4. Saccadic Test: Assesses the ability of the eyes to quickly shift from one point to another. This test provides information about central nervous system functions.

5. Optokinetic Test: Evaluates repetitive eye movements in response to a moving visual pattern, providing information about the functions of both the central and peripheral vestibular systems.

6. Head Shake Test: Observes eye movements while the head is shaken rapidly. This test can reveal asymmetry in the vestibular system.

7. Positional Tests: Evaluates eye movements in different head positions. The presence of nystagmus in certain head positions may indicate an issue in the inner ear. Tests like Dix-Hallpike, Supine Head Roll, and Deep Head Hanging are especially important for diagnosing benign paroxysmal positional vertigo (commonly known as “crystal displacement”).

• Dix-Hallpike Test

• Supine Head Roll Test

• Deep Head Hanging Test

8. Caloric Test: In this test, warm and cold air or water are applied sequentially to the external ear canal. These stimuli create fluid movement in the inner ear, leading to nystagmus. The caloric test compares the function of the vestibular systems in both ears.

9. VEMP (Vestibular Evoked Myogenic Potentials) Test: A non-invasive test used to evaluate the function of the inner ear and vestibular system, particularly the saccule and vestibulospinal pathways.

Purpose of VEMP Test:

• Saccule Function: The saccule is sensitive to head movements and gravity. The VEMP test measures the function of this structure and its associated vestibular nerves.
• Vestibulospinal Reflex: This reflex enables automatic muscle responses to maintain balance. The VEMP test evaluates this reflex pathway.

Types of VEMP Tests:

1. cVEMP (Cervical VEMP): Measures contraction responses of the sternocleidomastoid muscle, assessing the saccule and inferior vestibular nerve function.
2. oVEMP (Ocular VEMP): Measures responses in the inferior eye muscles, evaluating the utricle and superior vestibular nerve function.

10. Saccadometry Test: Saccadometry is an advanced oculomotor test that assesses the functional performance of brain regions and circuits involved in generating saccadic eye movements. It traditionally analyzes saccades based on latency, amplitude, and velocity.

By adding new analysis parameters, such as phase data and fatigue/error measurements over extended testing periods, saccadometry provides deeper insights into conditions like concussions, head trauma, neurodegenerative diseases, movement disorders, depression, and attention deficit disorders.

11. vOCR – Ocular Counter Roll Test:
A clinical test that evaluates otolith function using torsional eye-tracking algorithms. It provides an assessment of the otolith organs and their central connections.

Purpose of OCR Test:

Evaluates the functionality of the vestibular system and otolith organs, particularly in cases of otolith dysfunctions, vestibular nerve lesions, central vestibular disorders, dizziness, and imbalance.

12. VHIT (Video Head Impulse Test): Evaluates the vestibular system, specifically the semicircular canals, by measuring the vestibulo-ocular reflex (VOR). VHIT provides a quick and non-invasive assessment of vestibular function in both ears.

Tests Used to Evaluate Hearing

1. Pure Tone Audiometry:

Measures hearing thresholds using pure tones. In our clinic, we use pure tone audiometry, speech tests, and free-field tests in a soundproof room to accurately diagnose and treat hearing loss.

Free-Field Audiometry: Available at our clinic, this test evaluates the benefit of hearing aids in patients using such devices.

2. Speech Audiometry:

Complements pure tone thresholds by assessing middle ear, cochlea, auditory nerve, central auditory system, and auditory pathways. It also includes tests like the uncomfortable loudness level test, which provides valuable information about the source of hearing loss.

3. Behavioral Observation Audiometry:

Used for infants (0–4 months). Observes behavioral responses (e.g., blinking, head-turning, limb movements, crying, or sucking reflexes) to sound stimuli like pure tones, speech, or noise to determine hearing thresholds.

4. Visual Reinforcement Audiometry:

Used for infants and children (5–24 months). Measures hearing thresholds by observing responses to sound stimuli paired with visual cues (e.g., lighted boxes or moving toys).

5. Play Audiometry:

Used for children (24 months and older). Involves conditioning the child to perform tasks (e.g., dropping a block into a box) in response to hearing a sound to determine hearing thresholds.

Tests Used to Evaluate Tinnitus

In the assessment of tinnitus (ringing in the ears), various audiometric tests are used to determine the characteristics of hearing loss and tinnitus. These tests help to understand the type and severity of tinnitus and its impact on a person’s hearing. Here are the main audiometric tests used to assess tinnitus:

1. Pure Tone Audiometry:

Identifies the degree and type of hearing loss, providing insights into whether tinnitus is associated with hearing loss.

2. Tinnitus Matching Test:

Determines the frequency and intensity of the tinnitus by presenting tones to the patient and asking which tones closely resemble their tinnitus.

3. Tinnitus Masking Test:

Identifies the level at which tinnitus can be masked (no longer heard) by applying certain sounds, aiding in assessing the severity and management of tinnitus.

4. Tinnitus Handicap Inventory (THI):

Evaluates the impact of tinnitus on a patient’s quality of life through a questionnaire assessing social, emotional, and functional effects.

5. Loudness Discomfort Level (LDL) Test:

Measures the sound levels at which the patient experiences discomfort, often used to plan sound therapy for tinnitus patients.

6. Speech Audiometry:

Assesses speech comprehension in tinnitus patients, providing insights into hearing loss and speech understanding difficulties.

7. Tympanometry:

Measures middle ear pressure to detect fluid in the middle ear or ossicular chain dysfunction, along with Eustachian tube problems.

8. Acoustic Reflex Test:

Helps identify middle ear issues, including ossicular chain movement disorders and Eustachian tube problems, by measuring reflexive responses in the middle ear.

These tests collectively help diagnose the causes, types, and severity of balance and hearing issues, enabling accurate treatment planning.