Comprehensive Audiometry at Dr. Essa Lab

Audiometry at Dr. Essa Lab

Audiometry is the primary non-invasive diagnostic modality used to evaluate an individual’s hearing acuity, sensitivity, and range. By systematically measuring the ability to perceive various sound frequencies and intensities, this diagnostic evaluation plays a pivotal role in identifying, quantifying, and classifying hearing impairments. At Dr. Essa Lab, audiometry is performed in a controlled, clinical environment using state-of-the-art diagnostic audiometers and specialized soundproof testing booths. This ensures that external ambient noise does not interfere with the test results, providing the highest level of diagnostic precision for patients experiencing auditory symptoms.

The human auditory system is highly complex, consisting of the outer ear, the middle ear, the inner ear (cochlea), and the auditory nerve pathways leading to the brain’s temporal lobe. Audiometry evaluates the functional integrity of this entire pathway. The examination is divided into two primary testing methods: air conduction and bone conduction. Air conduction testing assesses the entire auditory system (outer, middle, and inner ear) by delivering sound waves through specialized headphones. Bone conduction testing bypasses the outer and middle ear by transmitting mechanical vibrations directly to the cochlea via a bone oscillator placed on the mastoid process. Comparing these two pathways allows clinicians to pinpoint the exact anatomical site of any hearing pathology.

The clinical importance of audiometry cannot be overstated. Hearing loss is not merely a sensory deficit; it is closely linked to cognitive decline, speech and language delays in children, social isolation, and reduced quality of life in adults. By establishing a precise baseline of a patient’s hearing thresholds, audiometry enables ENT specialists, audiologists, and primary care physicians to formulate targeted treatment plans. These interventions may range from medical management of middle ear fluid and surgical correction of structural abnormalities to the prescription of digital hearing aids or referral for cochlear implantation. At Dr. Essa Lab, we are committed to delivering accurate, reproducible, and clinically actionable audiometric data to support optimal patient outcomes.

Clinical Procedure: What to Expect

Patient Preparation

To ensure the utmost accuracy during an audiometry evaluation, patients should adhere to specific preparation guidelines. First and foremost, it is highly recommended to avoid exposure to loud noises, such as concerts, heavy machinery, personal audio devices at high volumes, or firearms, for at least 16 hours prior to the test. Exposure to loud sounds can induce a temporary threshold shift, which artificially worsens the test results and leads to an inaccurate diagnosis. If you work in a noisy environment, scheduling the test after a period of rest or over the weekend is ideal.

Additionally, patients should have their ears examined by a healthcare professional prior to the audiometry test to check for excessive cerumen (earwax) impaction. A significant accumulation of earwax can physically block sound waves, causing a false conductive hearing loss finding. If impaction is present, professional ear cleaning or wax removal should be performed before the evaluation. On the day of the test, patients should bring any previous audiograms or hearing reports for comparative analysis. No fasting, dietary restrictions, or sedation are required, and patients can safely take their routine medications.

During the Procedure

Upon arriving at Dr. Essa Lab, the patient is introduced to the clinical audiologist, who will conduct a brief interview regarding the patient’s medical history, symptoms, and noise exposure. The patient is then seated comfortably inside a specialized, double-walled sound-treated booth. This booth is engineered to block out all environmental noise, ensuring that only the test stimuli are perceived. The audiologist will place calibrated supra-aural or insert earphones over or inside the patient’s ears. These earphones are color-coded (typically red for the right ear and blue for the left ear) to ensure correct channel routing.

The test begins with pure-tone audiometry. The audiologist uses an audiometer to deliver tones at specific frequencies, ranging from low pitches (250 Hz) to high pitches (8000 Hz). The tones are presented at varying volumes, measured in decibels (dB). The patient is instructed to give a signal, such as pressing a hand-held button or raising a hand, every time they hear a tone, even if the sound is extremely faint. Each ear is tested individually. Following air conduction, a bone conduction oscillator is placed on the mastoid bone behind the ear to evaluate inner ear sensitivity directly. Speech audiometry may also be performed, where the patient repeats words spoken at different volumes to assess speech clarity and discrimination. The entire procedure is completely painless, non-invasive, and typically takes between 20 to 30 minutes.

When is an Audiometry Performed?

1. Evaluation of Age-Related Hearing Loss (Presbycusis)

Presbycusis is the gradual, progressive loss of hearing that occurs in many individuals as they age. It typically manifests as bilateral, symmetrical high-frequency hearing loss, making it difficult to understand speech, especially in noisy environments or when women and children are speaking. Physicians request audiometry for older adults presenting with these symptoms to determine the degree of hearing loss and to assess whether they are suitable candidates for hearing aids, which can significantly improve cognitive engagement and social communication.

2. Assessment of Noise-Induced Hearing Loss

Individuals exposed to chronic high-level noise, such as industrial workers, military personnel, musicians, or those using firearms, are at a high risk for noise-induced hearing loss. This condition often presents with a characteristic drop in hearing sensitivity at specific high frequencies, typically around 4000 Hz. Audiometry is performed as a routine screening tool in occupational health programs to detect early signs of cochlear damage before the patient notices significant communication difficulties, allowing for timely intervention and the implementation of hearing protection protocols.

3. Investigation of Unilateral or Bilateral Tinnitus

Tinnitus, often described as a ringing, buzzing, roaring, or hissing sound in the ears, is a common symptom that frequently accompanies underlying hearing loss. When a patient presents with persistent tinnitus, especially if it is unilateral (in one ear only), an audiometry test is crucial. The test helps identify any associated hearing deficits and assists ENT specialists in ruling out serious retrocochlear pathologies, such as an acoustic neuroma (vestibular schwannoma), which requires advanced imaging like an MRI if asymmetrical hearing loss is detected.

4. Monitoring Ototoxic Medication Effects

Certain medical treatments and medications are known to be ototoxic, meaning they can cause permanent or temporary damage to the sensory hair cells within the cochlea. Common ototoxic agents include platinum-based chemotherapy drugs (such as cisplatin), aminoglycoside antibiotics (such as gentamicin), and high-dose loop diuretics. Oncologists and infectious disease specialists routinely order baseline and serial audiometry tests during treatment to monitor for early signs of subclinical hearing loss, enabling them to adjust medication dosages if necessary to prevent permanent deafness.

5. Diagnosis of Chronic Otitis Media and Middle Ear Pathology

Chronic middle ear infections, fluid accumulation (otitis media with effusion), eustachian tube dysfunction, and structural issues like otosclerosis or a perforated tympanic membrane can significantly impair sound transmission. Physicians request audiometry to evaluate the impact of these middle ear pathologies on the patient’s hearing. The test identifies the presence and magnitude of an air-bone gap, which confirms conductive hearing loss and helps guide surgical decisions, such as tympanoplasty, myringotomy, or stapedectomy.

What Does an Audiometry Detect?

Audiometry is a highly sensitive diagnostic test capable of detecting a wide range of auditory system abnormalities. By analyzing the resulting audiogram, clinical specialists can identify and diagnose the following conditions and findings:

• Normal Hearing Thresholds: Hearing sensitivity within the normal range of 0 to 20 dB HL across all tested frequencies.
• Mild Conductive Hearing Loss: Mild impairment in sound transmission through the outer or middle ear, with thresholds between 21 and 40 dB HL.
• Moderate Conductive Hearing Loss: Moderate blockage of sound transmission, often due to fluid, ossicular stiffness, or tympanic membrane perforation.
• Severe Conductive Hearing Loss: Significant disruption of the physical sound conduction pathway, reaching thresholds up to 60 dB HL.
• Mild Sensorineural Hearing Loss: Early damage to the cochlea or auditory nerve, with thresholds between 21 and 40 dB HL.
• Moderate Sensorineural Hearing Loss: Moderate inner ear damage, affecting speech clarity and requiring amplification.
• Moderately-Severe Sensorineural Hearing Loss: Pronounced inner ear deficit, where normal conversational speech is highly difficult to perceive.
• Severe Sensorineural Hearing Loss: Severe cochlear or neural damage, where only very loud sounds can be detected.
• Profound Sensorineural Hearing Loss: Extreme hearing impairment, where most sounds are completely imperceptible without advanced amplification or cochlear implants.
• Mixed Hearing Loss: A combination of both conductive and sensorineural hearing loss in the same ear.
• High-Frequency Hearing Loss: Reduced sensitivity to high-pitched sounds, characteristic of presbycusis or early noise damage.
• Low-Frequency Hearing Loss: Impaired perception of low-pitched sounds, occasionally associated with conditions like Meniere’s disease.
• Noise-Induced Hearing Loss Notch: A distinct dip in hearing thresholds typically localized around 4000 Hz.
• Unilateral Hearing Loss: Hearing impairment isolated to one ear, requiring further diagnostic investigation.
• Bilateral Symmetrical Hearing Loss: Equal hearing loss in both ears, commonly seen in systemic, genetic, or age-related conditions.
• Bilateral Asymmetrical Hearing Loss: Discrepancies in hearing thresholds between the left and right ears, warranting retrocochlear evaluation.
• Presence of an Air-Bone Gap: A difference of 15 dB or more between air and bone conduction thresholds, confirming conductive pathology.
• Absence of an Air-Bone Gap: Overlapping air and bone conduction thresholds, confirming a purely sensorineural pathology.
• Elevated Speech Reception Threshold (SRT): The lowest level at which a patient can recognize speech is abnormally high, correlating with pure-tone loss.
• Poor Word Recognition Score (WRS): Impaired ability to understand speech even when presented at a comfortable volume, indicating cochlear or neural distortion.
• Carhart’s Notch: A specific decrease in bone conduction thresholds at 2000 Hz, highly indicative of otosclerosis.
• Fluctuating Hearing Loss: Variations in hearing thresholds over time, a classic hallmark of endolymphatic hydrops (Meniere’s disease).
• Pseudohypacusis: Discrepancies between subjective pure-tone thresholds and objective speech tests, suggesting non-organic or functional hearing loss.
• Eustachian Tube Dysfunction Effects: Mild, low-frequency conductive hearing loss associated with middle ear pressure imbalances.

Turnaround Time and Report Access at Dr. Essa Lab

At Dr. Essa Lab, we understand the importance of timely diagnostic results for guiding clinical decisions. The audiometry test is performed and analyzed in real-time by our qualified clinical audiologists. Once the test is completed, the audiogram is plotted, and a comprehensive report detailing the type, degree, and configuration of any detected hearing loss is compiled. This report is typically reviewed, finalized, and made available to the patient within a few hours of the procedure.

Patients can access their diagnostic reports conveniently through multiple channels. Dr. Essa Lab offers a secure online patient portal and a dedicated mobile application, allowing patients to view, download, and share their audiometry results with their referring physicians from the comfort of their homes. Physical copies of the report, complete with the plotted audiogram graphs, can also be collected directly from the front desk of the testing facility. Our administrative staff is always available to assist patients with any queries regarding report retrieval.

Audiometry Findings Overview

Structure / Parameter Evaluated	Normal Findings	Possible Abnormal Findings
Air Conduction (Right & Left Ear)	Thresholds between 0 to 20 dB HL across 250 to 8000 Hz	Thresholds > 20 dB HL, indicating some degree of hearing impairment
Bone Conduction (Right & Left Ear)	Thresholds between 0 to 20 dB HL; matches air conduction	Thresholds > 20 dB HL, indicating sensorineural or mixed hearing loss
Air-Bone Gap (ABG)	Less than 10 dB HL difference between air and bone conduction	ABG ≥ 15 dB HL, confirming a conductive hearing loss component
Speech Reception Threshold (SRT)	Within ± 6 dB of the Pure-Tone Average (PTA)	SRT significantly higher than PTA, indicating speech perception deficits
Word Recognition Score (WRS)	90% to 100% (Excellent speech discrimination and clarity)	Scores < 90%, indicating poor speech clarity (cochlear or neural pathology)
High-Frequency Sensitivity (4000 – 8000 Hz)	Thresholds ≤ 20 dB HL	Significant drop or notch, indicating noise damage or presbycusis
Low-Frequency Sensitivity (250 – 500 Hz)	Thresholds ≤ 20 dB HL	Elevated thresholds, indicating middle ear fluid or Meniere’s disease

Note: Diagnostic findings should always be interpreted by a qualified healthcare professional together with the patient’s symptoms, medical history, physical examination, laboratory investigations, previous imaging studies, and other relevant clinical information. Additional investigations or specialist consultation may be recommended depending on the findings.

Why Choose Dr. Essa Lab for Audiometry?

• Experienced Healthcare Professionals: Our audiometry tests are conducted by highly trained, certified clinical audiologists with extensive experience in diagnostic audiology.
• Patient-Focused Care: We prioritize patient comfort and clarity, ensuring that instructions are fully explained before and during the testing process.
• Quality Diagnostic Services: Dr. Essa Lab is committed to maintaining the highest standards of diagnostic accuracy and clinical excellence.
• Professional Reporting: Our reports feature detailed, easy-to-read audiograms that provide clear diagnostic insights for your referring physician.
• Modern Diagnostic Approach: We utilize advanced, regularly calibrated audiometers and sound-treated booths to eliminate external variables.
• Comfortable Environment: Our diagnostic centers are designed to provide a calm, welcoming, and professional atmosphere for patients of all ages.
• Convenient Locations: With an extensive network of branches across Karachi and other major cities, accessing quality diagnostic care is highly convenient.
• Commitment to Accurate Diagnosis: Established in 1987, Dr. Essa Lab has built decades of trust through reliable, evidence-based diagnostic reporting.