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This topic is very difficult for me to understand and also boring. Explain me this in a very very simplified manner and make me memorise this instantly so that I don’t forget about it.

Pure-Tone Audiometry (PTA) - Made Super Simple! 🎧

Let me break this down like you're hearing it for the first time (pun intended).

🧠 THE BIG IDEA IN ONE SENTENCE

PTA = A test where you play beeps at different volumes & frequencies to find out the softest sound a person can hear.

🏗️ THE 5 BUILDING BLOCKS

1. 🔧 THE MACHINE = Audiometer

Think of it as a fancy beep remote control that plays sounds at exact frequencies and volumes.

2. 🎧 HOW SOUND GETS TO YOUR EAR = Two Pathways

	Air Conduction (AC)	Bone Conduction (BC)
How	Headphones/earphones	Vibrator on skull behind ear
Tests	Outer + Middle + Inner ear	Inner ear (cochlea) mostly
Analogy	Sound travels through the air-filled tunnel of your ear	Sound bypasses the tunnel and vibrates directly to the cochlea

Golden Rule: Compare AC and BC to figure out WHERE the problem is.

3. 📊 THE GRAPH = Audiogram

Imagine a grid where:

X-axis (horizontal) = Frequency (pitch) → Low pitch (250 Hz) on left, High pitch (8000 Hz) on right
Y-axis (vertical) = Loudness → Goes DOWN (louder numbers at bottom = worse hearing)

Memory trick: "The worse your hearing, the deeper you sink on the graph" ⬇️

Symbols to remember:

Symbol	Meaning
O (open circle)	Right ear, Air conduction
X	Left ear, Air conduction
△ (triangle)	Bone conduction (unmasked)
[ or ]	Bone conduction (masked)

Right = Red = O (3 R's) | Left = bLue = X

4. 🔍 WHAT THE AUDIOGRAM TELLS YOU = 3 Types of Hearing Loss

Think of the ear as a pipe system:

Outer ear → Middle ear → Cochlea (inner ear) → Nerve
     ↑              ↑              ↑
  [AC tests all of these]   [BC bypasses to here]

🔴 Conductive Loss (pipe is blocked)

BC = Normal ✅ | AC = Bad ❌ → Big gap between them = Air-Bone Gap (ABG)
Cause: wax, fluid, perforated eardrum
Fix: usually treatable with medicine/surgery

🔵 Sensorineural Loss (SNHL) (cochlea/nerve damaged)

Both BC and AC are equally bad → No gap
Cause: noise damage, aging, genetic
Fix: hearing aids, cochlear implant

🟣 Mixed Loss

Both AC and BC are bad, but AC is worse → Gap still present
Combination of both above

Mega memory trick: "ABC Gap"

AC bad only = Conductive (has gap)

AC + BC both bad, no gap = Sensorineural

AC + BC both bad, gap still there = Mixed

5. 🎯 HOW THE TEST IS DONE = The "10 Down, 5 Up" Bracketing Method

Think of it like a guessing game:

Play a clearly audible beep → patient responds ✅
Turn it down 10 dB until they can't hear it ❌
Turn it up 5 dB until they hear it again ✅
Repeat until consistent → That's the threshold!

Standard frequency order tested: 1000 → 2000 → 4000 → 8000 → 500 → 250 Hz (Start at 1000 Hz because it's the most reliable, retest it at the end)

BONUS: 🎭 MASKING (The Tricky Part)

Problem: When you test one ear, the sound might sneak through the skull to the other (better) ear and give a false result. This is called cross-hearing.

Solution: Play noise (masking) into the non-test ear to keep it busy, so it can't "cheat" and hear the test signal.

When to mask (simple rules):

AC difference between ears ≥ 40 dB (with regular headphones) → mask!
BC of one ear is 10 dB better than the AC of either ear → mask!

🩺 DEGREES OF HEARING LOSS

Degree	Average Threshold
Normal	0-20 dB
Mild	21-40 dB
Moderate	41-70 dB
Severe	71-95 dB
Profound	96+ dB

Memory trick - "My Mother Sings Profusely" = Mild, Moderate, Severe, Profound

⚡ INSTANT RECALL CHEAT SHEET

PTA = Find softest beep a person can hear

AC (headphones) vs BC (skull vibrator)
→ Compare them to find WHERE the problem is

GAP (AC worse than BC by >10dB) = Conductive problem
NO GAP (both bad equally) = Sensorineural problem
GAP + both elevated = Mixed

Audiogram: Right=Red=O, Left=bLue=X
Y-axis goes DOWN = worse hearing

Method: 10dB DOWN, 5dB UP until threshold found

Masking = noise in good ear to stop it cheating

🎬 THE REAL-WORLD MOVIE ANALOGY

Imagine your ear is a movie theatre:

AC = Normal ticket entry (through front door, hallway, seats)
BC = VIP secret entrance directly to the cinema screen

If the hallway is blocked (wax/fluid) but the screen works fine → Conductive loss (front blocked, VIP entry fine)

If the screen itself is damaged → Sensorineural loss (both entrances lead to a bad screen)

If both the hallway is blocked AND the screen is damaged → Mixed loss

That's everything in your 10 pages, simplified into one story. The key thing to remember every time: compare AC and BC → gap or no gap → that tells you everything about the type of hearing loss!

Pure tone Audiometry , impedance Audiometry, speech Audiometry , tuning fork tests, acoustic reflex, otoacoustic emission, bear, Sisi , recruitment, abbr and different other Audiometry tests all in detail from ENT standard textbooks for exam and teach me whole in simplified language

Reading File

Finding Sources

Reading File

Finding Sources

I now have all the textbook data I need. Let me write the full comprehensive simplified guide now.

🎧 THE COMPLETE AUDIOMETRY GUIDE

Everything from ENT Standard Textbooks - Simplified for Instant Memory

🗺️ THE BIG MAP FIRST

Think of the ear as a 3-part factory:

OUTER EAR → MIDDLE EAR → INNER EAR (Cochlea) → NERVE → BRAIN
  [Canal]   [Eardrum+Ossicles]  [Hair cells]    [VIII CN]  [Cortex]
     ↑              ↑                 ↑               ↑         ↑
   AC tests    Impedance          OAE / SISI       ABR/BEAR   Speech
  all of this  Audiometry         Audiometry       Audiometry  Audiometry

Every audiometry test is designed to pinpoint WHICH part of the factory is broken.

🔱 PART 1: TUNING FORK TESTS

Your cheapest, fastest, bedside tool. No electricity needed. The 512 Hz fork is the gold standard.

Why NOT below 512 Hz? - Low-frequency forks can be FELT (vibrotactile) instead of heard - confuses the patient.

🔔 Test 1: RINNE TEST

One word summary: Compares AC vs BC in the SAME ear

	Air Conduction (AC)	Bone Conduction (BC)
How	Fork 2cm from ear canal	Fork on mastoid bone
Tests	Full ear pathway	Inner ear only

Result:

AC > BC = Positive Rinne = Normal OR Sensorineural loss
BC > AC = Negative Rinne = CONDUCTIVE LOSS (minimum ~20 dB gap with 512 Hz)

Memory trick: "Positive = Perfect" (normal or SNHL). "Negative = Not conducting well" (conductive loss)

Watch out: In severe SNHL, the dead ear may give a FALSE negative Rinne! The fork on the mastoid of the deaf ear is actually being heard by the GOOD ear across the skull. This is called a "False negative Rinne."

🔔 Test 2: WEBER TEST

One word summary: Lateralization test - compares BOTH ears

Procedure: Fork placed on the MIDLINE (forehead, nasal dorsum, central incisors, or chin).

Results:

Sound goes to...	Meaning
Midline (equal)	Normal OR equal loss in both ears
Affected (blocked) ear	CONDUCTIVE loss in that ear
Opposite (good) ear	SENSORINEURAL loss in the bad ear

The trick to remember Weber:

Conductive = sound goes to the BAD ear (because background bone noise is blocked, so the test signal is clearer)

SNHL = sound goes to the GOOD ear (because the bad cochlea can't pick it up)

Mnemonic: "SHE" = SNHL goes to the Healthy Ear

🔔 Test 3: SCHWABACH TEST

One word summary: Compares patient's BC to a normal-hearing EXAMINER

Prolonged Schwabach = Patient hears LONGER than examiner = Conductive loss (sound not escaping through middle ear normally)
Diminished Schwabach = Patient hears SHORTER than examiner = SNHL (damaged cochlea)
Equal Schwabach = Normal

🔔 Test 4: BING TEST (Occlusion Effect)

One word summary: Tests if blocking the ear canal INCREASES bone conduction

Fork on mastoid. Then block the ear canal with a finger.
Positive Bing = Sound gets LOUDER when you block the ear = Normal OR SNHL (occlusion effect present)
Negative Bing = No change in loudness = CONDUCTIVE LOSS (occlusion effect absent - because the middle ear is already "blocked")

📊 COMPLETE TUNING FORK SUMMARY TABLE

(Source: KJ Lee's Essential Otolaryngology, Scott-Brown's, Shambaugh)

Test	Normal	Conductive Loss	SNHL
Rinne	AC > BC (+ve)	BC > AC (-ve)	AC > BC (+ve)
Weber	Midline	To BAD ear	To GOOD ear
Schwabach	Equal to examiner	Prolonged	Diminished
Bing	Positive (louder with occlusion)	Negative (no change)	Positive

📊 PART 2: PURE TONE AUDIOMETRY (PTA)

(Already covered in the previous session - quick recap with new exam points)

The 10 DOWN, 5 UP Bracketing Method:

Start audible → ↓10dB until NO response → ↑5dB until RESPONDS
Repeat until 2 out of 3 ascending responses = THRESHOLD

Standard test order: 1000 → 2000 → 4000 → 8000 → 500 → 250 Hz (retest 1000 Hz at the end)

Why start at 1000 Hz? Most reliable frequency, easiest for patients to detect.

Air-Bone Gap (ABG): Difference between AC and BC thresholds at same frequency.

ABG ≥ 10 dB = Conductive component
ABG ≥ 15 dB = Clinically significant

🫙 PART 3: IMPEDANCE AUDIOMETRY (Immittance)

Think of the middle ear as a spring system. Impedance = how much it resists sound. Admittance = how easily sound flows through. The machine measures ADMITTANCE (compliance).

3A: TYMPANOMETRY

What it does: Varies air pressure in the sealed ear canal (+200 to -400 daPa) and measures how compliant (floppy/stiff) the eardrum is at each pressure.

The output = TYMPANOGRAM

Jerger Classification of Tympanograms:

Type	Peak	Pressure	Meaning	Example
Type A	Normal peak	Near 0 daPa	Normal middle ear	Normal
Type As	Shallow peak (low compliance)	Near 0 daPa	Stiff middle ear	Otosclerosis, tympanosclerosis
Type Ad	Deep/tall peak (high compliance)	Near 0 daPa	Discontinuity or lax TM	Ossicular discontinuity, flaccid TM
Type B	Flat line (NO peak)	-	Fluid or perforation	Otitis media with effusion, perforation
Type C	Peak present but shifted LEFT	Negative pressure	Eustachian tube dysfunction	Early OME, negative ME pressure

Memory trick: "A = Aight (fine), As = Arthritic (stiff), Ad = Abnormally floppy, B = Blocked (no peak), C = Can't equalize pressure"

Type B with:

Small ear canal volume = Fluid in middle ear (intact drum)
Large ear canal volume = Perforated drum or patent grommet

3B: ACOUSTIC REFLEX (Stapedial Reflex)

The reflex arc:

Sound → VIII Nerve → Cochlear nucleus → Superior olive → VII nerve → Stapedius muscle → Contracts → Stiffens ossicular chain

Normal reflex threshold: 70-100 dB above HTL (Hearing Threshold Level)

Two ways to measure:

	Ipsilateral	Contralateral
Signal & measurement	Same ear	Different ears
Tests	Whole reflex arc	Full crossed pathway (both sides)

What Acoustic Reflex Tells You:

Finding	Meaning
Reflex present	At minimum, VII nerve and stapedius are working; cochlea must be working somewhat
Reflex absent - normal tympanogram	Suspicion of retrocochlear lesion (VIII nerve/brainstem)
Reflex at lower-than-normal level	Cochlear loss with RECRUITMENT
Reflex absent - flat tympanogram	Middle ear problem (already expected)

Acoustic Reflex DECAY Test:

Stimulus held for 10 seconds at 10 dB above reflex threshold
Normal: Reflex amplitude stays the same
Abnormal (decay): If reflex amplitude falls to 50% within 5 seconds = retrocochlear lesion (VIII nerve tumor = Acoustic Neuroma/Vestibular Schwannoma)

Memory trick: "Decay = Dying nerve"

🗣️ PART 4: SPEECH AUDIOMETRY

Tuning forks use pure beeps. PTA uses pure tones. Speech audiometry uses REAL WORDS - tests how well the brain actually understands speech.

Three Main Measures:

1. Speech Detection Threshold (SDT) / Speech Awareness Threshold (SAT)

Lowest level at which patient can DETECT speech is present (doesn't need to understand it)
Used in: infants, non-verbal patients, language barrier

2. Speech Recognition Threshold (SRT) - THE MAIN ONE

Lowest level at which patient can correctly repeat SPONDEES in 50% of presentations
Spondee = 2-syllable word with EQUAL stress on both syllables (railroad, eardrum, sidewalk, icecream, cowboy)
Gold rule: SRT should be within ±6 dB of the Pure Tone Average (PTA at 500, 1000, 2000 Hz)
If SRT and PTA disagree by more than 10 dB → suspect pseudohypacusis (fake hearing loss)

3. Word Recognition Score (WRS) / Speech Discrimination Score (SDS)

Percentage of Phonetically Balanced (PB) monosyllabic words correctly repeated at 25-35 dB above SRT
Tests the quality of hearing, not just the quantity

Interpretation of WRS:

Score	Meaning
90-100%	Normal
76-88%	Slight difficulty
60-74%	Moderate difficulty
40-58%	Poor
≤ 40%	Very poor

Performance-Intensity (PI) Function & ROLLOVER:

Plot WRS at multiple intensity levels. The curve should RISE then PLATEAU.

Cochlear loss: Rises normally, may plateau slightly lower
Retrocochlear (VIII nerve) lesion: Rises then FALLS sharply at high intensities = "Rollover"
Rollover ratio = (PB max - PB min) / PB max
Rollover ratio ≥ 0.30 = VIII nerve lesion (retrocochlear)

Memory trick: "Rollover = nerve is rolled over and not working at high volumes"

⚡ PART 5: OTOACOUSTIC EMISSIONS (OAE)

One of the coolest discoveries in audiology! Healthy cochlear outer hair cells (OHCs) don't just RECEIVE sound - they also EMIT sound back out! We can record these emissions.

The principle: When sound goes IN, OHCs vibrate and produce a faint echo that travels BACK through the middle ear and into the ear canal, where we record it with a tiny microphone.

OAEs are present ONLY if:

The middle ear is healthy (to transmit the emission out)
The outer hair cells are healthy (to generate the emission)

Two Types of OAE:

	TEOAE (Transient Evoked OAE)	DPOAE (Distortion Product OAE)
Stimulus	Clicks (broad frequency)	Two simultaneous pure tones (f1 and f2)
Response	Echo after the click	Distortion product at 2f1-f2
Frequency range	500-4000 Hz	1000-8000 Hz (better for high freq)
Best for	Newborn hearing screening	Detailed cochlear mapping, ototoxicity monitoring
Clinical use	Neonatal screening (quick pass/fail)	Serial monitoring, detailed assessment

OAE Clinical Rules:

OAE Present + Normal hearing = Outer hair cells fine ✅
OAE Absent + Normal ABR = Possible central issue
OAE Present + Absent ABR = Auditory Neuropathy Spectrum Disorder (ANSD) - outer hair cells fine but nerve is not conducting
OAE Absent = Hearing loss > 25-30 dB OR middle ear problem

Memory trick: "OAE = Outer hair cells' Answer to Everyone. If they're alive, they reply."

🧠 PART 6: ABR / BEAR (Brainstem Evoked Auditory Response)

This test bypasses the patient's cooperation entirely. It records electrical brain waves in response to clicking sounds. The patient can be asleep, sedated, or a newborn baby.

Full name: Auditory Brainstem Response (ABR) = BERA = BEAR = BAER

Setup: Electrodes on scalp. Clicks or tone pips presented. Computer averages hundreds of responses to produce a waveform.

The 5 Waves & Their Origins:

Wave	Origin	Latency
I	Distal VIII nerve (cochlear nerve)	~1.5 ms
II	Proximal VIII nerve / cochlear nucleus	~2.5 ms
III	Superior olivary complex (pons)	~3.5 ms
IV	Lateral lemniscus	~4.5 ms
V	Inferior colliculus (midbrain)	~5.5 ms

Memory trick: "Ear Enters Every Lateral Inferior" = VIII nerve → Cochlear nucleus → Superior olive → Lateral lemniscus → Inferior colliculus

Clinically we focus on Waves I, III, and V (most reliable)

How to Interpret ABR:

Finding	Meaning
All waves delayed (increased absolute latency)	Conductive hearing loss
Normal wave I, delayed wave V (increased I-V interpeak latency)	Retrocochlear lesion (VIII nerve or brainstem)
Wave V threshold elevated	Hearing loss (can estimate audiogram)
No waves at all	Profound deafness OR no response pathway
Present OAE + Absent ABR	Auditory Neuropathy

Key interpeak intervals:

I-III = ~2 ms (normal)
III-V = ~2 ms (normal)
I-V = ~4 ms (normal)
I-V > 4.4 ms = ABNORMAL = retrocochlear pathology

Clinical Uses of ABR:

Newborn hearing screening (universal)
Threshold estimation in non-cooperative patients (infants, malingerers)
Acoustic neuroma detection (vestibular schwannoma)
Intraoperative monitoring during posterior fossa surgery

🔬 PART 7: SITE-OF-LESION TESTS

(SISI, ABLB, Tone Decay, Recruitment, Bekesy)

These tests help determine: Is the hearing loss in the COCHLEA or in the VIII NERVE? (Note: Most are now replaced by ABR + MRI, but still tested in exams)

7A: RECRUITMENT

What is it? An abnormal rapid growth of loudness. A person with cochlear hearing loss cannot hear soft sounds (raised threshold), but once the sound crosses threshold, it becomes loud VERY quickly - almost normally loud.

Imagine: A light switch that only turns ON when you push it very hard, but once it turns on, it's BLINDING bright.

Recruitment = COCHLEAR (inner hair cell) damage
No recruitment = RETROCOCHLEAR (nerve) damage

How to detect recruitment:

Acoustic reflex at low levels above threshold
ABLB test
SISI test (high score)
Loudness discomfort level (UCL) is not raised despite elevated threshold

7B: SISI TEST (Short Increment Sensitivity Index)

What it does: Tests if a person can detect tiny 1 dB increases superimposed on a continuous tone at 20 dB above threshold.

Procedure: 20 brief 1 dB increments are given. Patient presses button when they notice a change.

Scoring: % of increments detected out of 20 presentations.

Score	Site of Lesion
≥ 70% (High SISI)	COCHLEAR lesion (recruitment present - they detect tiny changes)
≤ 30% (Low SISI)	RETROCOCHLEAR / Neural lesion OR Normal hearing
30-70%	Equivocal

Memory trick: "High SISI = Cochlear (they're SISIitive to small changes)"

7C: ABLB TEST (Alternate Binaural Loudness Balance)

Used in: Unilateral SNHL only

What it does: Patient alternately hears a tone in the GOOD ear and the BAD ear. They balance the loudness - adjust one until both feel equally loud.

Interpretation:

Recruitment present (Cochlear): Equal loudness is reached at EQUAL intensity levels (dB HL) - i.e., the bad ear "catches up" to the good ear in loudness
No recruitment (Retrocochlear): Equal loudness requires MORE intensity in the bad ear (the bad ear never catches up)

Memory trick: "ABLB: A Balance test. Loudness Balance = cochlear recruitment found"

7D: TONE DECAY TEST (Auditory Adaptation / Fatigue Test)

What it does: Plays a continuous tone at threshold level. The patient indicates when they can no longer hear it. If they stop hearing it, intensity is raised by 5 dB and timing restarts.

Principle: Normal ears can hear a continuous tone indefinitely. Damaged VIII nerve "fatigues" rapidly.

Decay	Meaning
0-5 dB	Normal
≤ 25 dB	Normal to cochlear
> 25 dB	Retrocochlear (VIII nerve lesion - ACOUSTIC NEUROMA)

Memory trick: "Tone Decay > 25 = Nerve is Decaying (acoustic neuroma)"

7E: BEKESY AUDIOMETRY

What it does: Patient controls their own threshold using a button. The audiometer sweeps across frequencies automatically. Two runs: one with pulsed tone, one with continuous tone.

Bekesy Types:

Type	Pattern	Meaning
Type I	Pulsed = Continuous (overlap)	NORMAL or Conductive
Type II	Continuous drops ~20 dB below pulsed (especially at high freq)	COCHLEAR
Type III	Continuous drops >20 dB, keeps falling	VIII NERVE lesion (acoustic neuroma)
Type IV	Continuous drops >20 dB across ALL frequencies	VIII NERVE lesion
Type V	Continuous is BETTER than pulsed (reverse)	Functional (non-organic) hearing loss

Memory trick: "Type I = Innocent. Type II = Cochlea. Type III/IV = Three/Four Nerve damage. Type V = V for Very fake"

🔁 PART 8: MASKING RULES (Clinical)

(Source: Scott-Brown's, Table 51.1)

When do you MASK (put noise in the non-test ear)?

Rule	Situation	Action
Rule 1	AC thresholds differ by ≥40 dB (supra/circum-aural headphones) OR ≥55 dB (insert earphones)	Retest AC of worse ear while masking better ear
Rule 2	BC threshold of one ear is better than the AC threshold of EITHER ear by ≥10 dB	Retest BC while masking opposite ear
Rule 3	Rule 1 not applicable, but BC of ear A is ≥40 dB (or 55 dB insert) better than not-masked AC of ear B	Retest AC of ear B while masking ear A

🧪 PART 9: OTHER TESTS

9A: STENGER TEST (for functional/malingering hearing loss)

Principle: When the same tone is presented to both ears simultaneously, only the louder one is perceived (Stenger principle).

Used when: Suspecting unilateral non-organic (faked) hearing loss.

Present tone at 10 dB ABOVE the supposed bad ear's threshold and at 10 dB BELOW the good ear's threshold.
Positive Stenger: Patient DENIES hearing the tone (because they can't admit the "bad" ear is hearing) → CONFIRMS functional/fake loss
Negative Stenger: Patient admits hearing the tone → organic loss

9B: SPEECH BANANA (on the Audiogram)

The region on the audiogram where all speech sounds fall = frequency 500-4000 Hz, levels 20-60 dB HL. Looks like a banana shape. Any hearing loss covering the speech banana = communication difficulty.

9C: AUDITORY PROCESSING DISORDER (APD)

PTA can be NORMAL
Patient complains of difficulty understanding speech in NOISE
Tests: Dichotic listening, speech in noise tests, gap detection, time-compressed speech
Site: Central auditory nervous system (above brainstem)

🏆 MEGA SUMMARY TABLE: THE CHEAT SHEET FOR EXAMS

Test	What it measures	Cochlear finding	Retrocochlear finding
PTA	Hearing threshold	Elevated threshold, config varies	Elevated threshold, often asymmetric
Rinne	AC vs BC	AC > BC (+ve)	AC > BC (+ve)
Weber	Lateralization	To good ear	To good ear
Tympanometry	Middle ear compliance	Normal (Type A)	Normal (Type A)
Acoustic reflex	Stapedial reflex	Present at low SL (recruitment)	Absent or decays
Reflex decay	Nerve fatigue	Absent/minimal	POSITIVE (>50% in 5 sec)
OAE	OHC function	Absent (if >30 dB loss)	Usually PRESENT (if cochlea OK)
ABR	Neural pathway	Normal I-V interval	Prolonged I-V > 4.4 ms
SISI	Small increment detection	HIGH ≥70%	LOW ≤30%
ABLB	Loudness balance	Recruitment present (equal HL)	No recruitment
Tone decay	Auditory fatigue	≤25 dB	>25 dB
Bekesy	Auditory adaptation	Type II	Type III/IV
WRS/Rollover	Speech discrimination	Normal/slight rollover	ROLLOVER ≥0.30

🧠 INSTANT MEMORY ANCHORS

For Tuning Fork Tests:

"Weber SHE CONFERS"

SNHL → Healthy Ear
CONductive → FERS to the bad ear (confers = conferring with the bad side)

For Impedance Types:

"A = OK, As = Stiff, Ad = Dangling, B = Blocked, C = Can't equalize"

For Site of Lesion:

"Cochlea = HIGH, Neural = LOW" (SISI scores) "Cochlea = Recruits, Neural = Decays" (loudness growth vs fatigue)

For ABR Waves:

"Eight-Eleven-Five" = Wave I at 1.5, Wave III at 3.5, Wave V at 5.5 ms Or: "Ear Enters Every Lateral Inferior" (anatomical pathway)

For Speech Audiometry:

"SRT ± 6 dB from PTA" (if bigger gap = suspect fake/non-organic hearing loss) "Rollover ≥ 0.30 = VIII nerve"

Degrees of Hearing Loss:

"My Mother Sings Professionally" = Mild (21-40), Moderate (41-70), Severe (71-95), Profound (96+)

🎯 EXAM QUICK FIRE Q&A

Q: Weber lateralizes to right ear. What does it mean? A: Either RIGHT ear has conductive loss OR LEFT ear has SNHL.

Q: OAE present but ABR absent. Diagnosis? A: Auditory Neuropathy Spectrum Disorder (ANSD) - outer hair cells fine, nerve not conducting.

Q: Type B tympanogram with small ear canal volume. Diagnosis? A: Fluid in middle ear (otitis media with effusion) - intact TM.

Q: Type B tympanogram with large ear canal volume. Diagnosis? A: Tympanic membrane perforation OR patent grommet.

Q: Tone decay > 25 dB. Diagnosis? A: Retrocochlear lesion - acoustic neuroma (vestibular schwannoma).

Q: High SISI + present recruitment + Bekesy Type II. Site? A: COCHLEA.

Q: Absent SISI + absent recruitment + Bekesy Type III + ABR prolonged I-V interval. Site? A: RETROCOCHLEAR (VIII nerve - acoustic neuroma).

Q: SRT is 40 dB but PTA average is 20 dB. What do you suspect? A: Pseudohypacusis (non-organic/functional hearing loss).

Q: Acoustic reflex decays to 50% within 5 seconds. What lesion? A: Retrocochlear - VIII nerve lesion.

Sources: Scott-Brown's Otorhinolaryngology Vol 2, KJ Lee's Essential Otolaryngology, Shambaugh Surgery of the Ear, Cummings Otolaryngology

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