Neuro Anatomy (Chap 6-11)

Front 1

Chap 6

What does the gray mater contain?

Back 1

Gray communicating rami contain unmyelinated postganglionic sympathetic fibers.

Found at all levels of the spinal cord.

Front 2

FA: p.358

What are neural tube defect associated with?

Back 2

Associated with low folic acid intake during pregnancy.

Also can be identified with elevated alpha-fetoprotein in amniotic fluid and maternal serum (so its increased in patients carrying children with neural tube defects)

Front 3

Oops..chap 4

What is a decrease in alpha-fetoprotein associated with?

Back 3

Down's sydrome = decrease in alpha fetoprotein

Front 4

FA: 358

What is spina bifida occulta?

Back 4

Spina bifida occulta: failure of bony spinal canal to close, but no structural herniation.

Will see tuft of hair
Usually seen at the lower vertebral levels.

Front 5

FA: p.358

What is a meningocele?

Back 5

Meningocele: meninges herniated through a spinal canal defect

Front 6

FA: p.358

What is a meningomyelocele?

Back 6

Meningomyelocele: meninges and spinal cord herniate through spinal canal defect

Front 7

Chap 6

What does the white mater contain?

Back 7

White communicating rami contain myelinated preganglionic sympathetic fibers. They are found from T-1 to L-3 (the extent of the lateral horn)

Front 8

Chap 6

Cord segment and Muscle of:

Ankle jerk reflex

Back 8

Ankle jerk reflex: S1 and gastrocnemius

Front 9

Chap 6

Cord segment and Muscle of:
Knee jerk

Back 9

Knee jerk:
L2-L4
Quadriceps

Front 10

Chap 6

Cord segment and Muscle of:
Biceps jerk

Back 10

Biceps jerk:
C5 and C6
Biceps

Front 11

Chap 6

Cord segment and Muscle of:
Forearm jerk

Back 11

Forearm jerk:
C5-C6
Brachioradialis

Front 12

Chap 6

Cord segment and Muscle of:
Triceps jerk

Back 12

Triceps jerk
C7-C8
Triceps

Front 13

Chap 6

Where is the phrenic nucleus located?
Function?

Back 13

Phrenic nucleus: from C3-C6

Function: respiratory center

Front 14

Chap 6

Where is the nucleus dorsalis of Clark?

Back 14

Nucleus dorsalis of Clark:
from C8-L3

It gives rise to the dorsal spinocerebellar tract (proprioceptive info from body to cerebellum)

Front 15

Chap 6

Where is the spinal accesory nucleus?
Function?

Back 15

Spinal accessory nucleus: from C1-C6

Function: it is the motor portion of CN XI (spinal accessory n.) that provides innervation to the trapezius and sternomastoid

It is located in the medulla.

Front 16

Chap 6

What is the myotatic reflex?

Back 16

Myotatic reflex:
monosynaptic and ipsilateral muscle stretch reflex. Like all reflexes, it has an afferent and efferent limb. Afferent limb = muscle spindle (receptor) and DRG and its Ia fiber
Efferent limb = ventral horn motor neuron that innervates striated muscle effector.

Interruption = areflexia

Front 17

Chap 7

What is the function of the dorsal column-medial lemniscus pathway?

Back 17

The dorsal column-medial lemniscus pathway mediates tactile discrimination, vibration, form recognition, and joint/muscle sensation (proprioception).

Front 18

FA p.353

Primitive reflexes:
Moro reflex

Back 18

Moro reflex: extension of limbs when startled

Front 19

FA p.353

Primitive reflexes:
When do they disapear? Reemerge?

Back 19

Disappear: within first year
Reemerge: with frontal lobe lesion

Front 20

FA p.353

Primitive reflexes:
Rooting reflex

Back 20

Rooting reflex: nipple seeking

Front 21

FA p.353

Primitive reflexes:
Palmar reflex

Back 21

Palmar reflex: grasps objects in palm

Front 22

FA p.353

Primitive reflexes:
Babinski reflex

Back 22

Babinski: large toe dorsiflexes with plantar stimulation

Front 23

FA p.352

Where is a pudendal nerve block administered?

Back 23

Ischial spine

Front 24

FA p.352

Where is appendix located in reference to the anterior superior iliac spine?

Back 24

Appendix: 2/3 of the way up from the umbilicus to the anterior superior iliac spine (Mc.Burneys point)

Front 25

FA p.352

What procedure uses the iliac crest as a ID point?

Back 25

Lumbar puncture

Front 26

Chap 7

What receptors feed into the dorsal column-medial lemniscus pathway?

Back 26

Dorsal column:
Pacini's and meissner's corpuscles
(joint receptors, muscle spindles, Golgi tendon organs)

Front 27

Chap 7

What are the first-order neurons of the dorsal column? Where are they located?

Back 27

First order neurons of dorsal column:
Located in the dorsal root ganglia at all levels. They give rise to:
1. lower extremity: gracile fasciculus
2. upper extremity: cuneate fasciculus

Front 28

Chap 7

Describe the pathway of the dorsal column:

Back 28

From skin --> dorsal root ganglia at all levels --> goes to gracile fasciculus (if from LE) and cuneate fasciculus (if from UE) --> turns into nucleus gracilis and cuneatus in the medulla(?) --> internal arcuate fibers --> decussates as medial lemniscus --> enters medulla as medial lemniscus --> ascends to ventral posterolateral nucleus of the thalamus --> cerebral cortex (postcentral gyrus in distribution of homunculus)

Front 29

Chap 7

Where are the second order neurons of the dorsal column/medial lemniscus tract?

Back 29

Second order neurons of dorsal column are located in the gracile and cuneate nuclei of caudal medulla. They give rise to the axons and internal arcuate fibers that decussate and form a compact fiber bundle (ie medial lemniscus). The medial lemniscus ascends through the contralateral brain stem and terminates in the ventral posterolateral nucleus of the thalamus.

Front 30

Chap 7

Where are the third order neurons of the dorsal column/medial lemniscus tract?

Back 30

Third order neurons: located in the ventral posterolateral nucleus of the thalamus.
They project through the POSTERIOR LIMB of the INTERNAL CAPSULE to the postcentral gyrus (primary somatosensory cortex) which is Brodman's area 3, 1, 2.

Front 31

Chap 7

What happens in a transection of the dorsal column:
1. above the sensory decussation?
2. in the spinal cord?

Back 31

1. Above the sensory decussation: transection results in contralateral loss of the dorsal column modalities
2. In the spinal cord: transection results in ipsilateral loss of dorsal column modalities (pressure, vibration, touch, position, movement, proprioception)

Front 32

Chap 7

What is the function of the lateral spinothalamic tract?

Back 32

Lateral spinothalamic tract:
mediates pain and temperature sensation

Front 33

Chap 7

What are the receptors for the lateral spinothalamic tract?

Back 33

Receptor for lateral spinothal tract:
free nerve endings transmit via slow (C-IV) and fast (A-delta, III) pain fibers.

Front 34

Chap 7

What are the first order neurons of the lateral spinothalamic tract?

Back 34

First order neurons of the lateral spinothalamic tract:
found in dorsal root ganglia at all levels.
They project axons to the spinal cord through the dorsolateral tract of Lissauer (lateral root entry zone) to second-order neurons.

Front 35

Chap 7

What are the second order neurons of the lateral spinothalamic tract?

Back 35

Second order neurons of the lateral spinothalamic tract:
Found in the dorsal horn. They give rise to axons that decussate in the ventral white commissure and ascend in the contralateral spinal column.

Front 36

Chap 7

What are the third order neurons of the lateral spinothalamic tract?

Back 36

Third-order neurons of lateral spinothalamic tract:
Found in the ventralposterolateral nucleus (VPL).
They project through the posterior limb of the internal capsule to the primary somatosensory cortex (Brodmans 3, 1, 2)

Front 37

Chap 7

Transection of the lateral spinothalmic tract?

Back 37

CONTRALATERAL loss of pain and temperature below the lesion.

Front 38

Chap 7

What is the function of the lateral corticospinal tract?

Back 38

Lateral corticospinal tract:
Mediates voluntary skilled motor activity, primarily of the upper limbs.
It is not fully myelinated until the end of the second year (Babinski)

Front 39

Chap 7

Where does the lateral corticospinal tract originate?

Back 39

Lateral corticospinal tract originates from layer V of the cerebral cortex from three cortical areas:
1. premotor cortex (Brodmans 6)
2. primary cortex (Brodmans 4)
3. primary sensory cortex (Brodmanns 3, 1, 2)

All of these areas come specifically from the arm, face, and foot area of homunculus (arm,face: lateral; foot: paracentral)

Front 40

Chap 7

Where does the lateral coricospinal tract terminate?

Back 40

Lateral corticospinal tract terminates:
contralaterally (after decussation in medulla) on to ventral horn motor neurons

(note: ventral corticospinal tract does not decussate in medulla)

Front 41

Chap 7

Describe the full course of the lateral corticospinal tract:

Back 41

Lateral corticospinal tract:
1. from cortex to telencephalon (posterior limb of internal capsule)
2. to the midbrain (middle of crus cerebri)
3. to the pons (base of pons)
4. to the medulla (90% decussate)
5. to the spinal cord (dorsal quadrant of the lateral funiculus

Front 42

Chap 7

What happens in a transection of the lateral corticospinal tract?

Back 42

Lateral corticospinal tract transection:
1. above the motor decussation: contralateral spastic paresis and Babinski sign (upgoing toe)
2. In the spinal cord: results in ipsilateral spastic paresis and Babinski's sign

Front 43

Chap 7

What is the hypothalamospinal tract?

Back 43

The hypothalamospinal tract is one that projects without interruption from the hypothalamus to the intermediolateral column at T1 and T2 of the spinal cord.

Front 44

Chap 7

What is a clinical correlation to the hypothalamospinal tract?

Back 44

Horner's syndrome: it is associated with a lesion above T1. The 3-neuron oculosympatheitic pathway that is severed projects from the hypothalamus to the intermediolateral column and then to the superior cervical (symp) ganglion, and finally to the pupil, the smooth muscle of the eyelids, and the sweat glands of the forehead and face.

Horner's is associated with PAM (PAM is horny)
Ptosis (slight eyelid dropping)
Anhidrosis (absence of sweating) and flushing (rubor) on one side of face.
Miosis: pupil constriction

Front 45

FA, p.364

What two things are related to Horner's syndrome as causes?

Back 45

1. Pancoast tumor
2. Late-stage syringomyelia

Front 46

FA p.365

What two vessels may be affected in Horner's syndrome?
Why?

Back 46

Internal and external carotid arteries

They are located very close to the superior cervical ganglion that is effected in Horner's syndrome.

Front 47

Chap 8

What causes nonfacial upper motor neuron lesions?

Back 47

UMN lesions: caused by transection of the corticospinal tract or destruction of the cortical cells of origin.

They result in ipsilateral spastic paresis with pyramidal signs (Babinski, weakness, increase reflexes, and tone)

"Everything goes up: tone, DTR, and toes"

Front 48

Chap 8

What causes nonfacial lower motor neuron lesions?

Back 48

LMN lesions caused by damage to motor neurons (these are in the anterior/ventral horns gray mater - not any tract). This causes IPSILATERAL flaccid paralysis, decreased muscle tone and mass, decreased reflexes, and toes down.

"Everything goes down"

Front 49

Chap 8, FA p.364

Two examples of lower motor neuron disease?

Back 49

1. Poliomyelitis: poliovirus (ssRNA linear nonenv & in the picornavirus with echovirus, rhinovirus, coxsackievirus, and HAV -- PERCH). This virus comes in via fecal-oral, replicates in oropharnyx --> goes to SI and gets into blood headed to CNS.

2. Werdng-Hoffmann dz: auto-recessive, "floppy baby" at birth, tongue fasiculations, death avg 7 yo

Front 50

Chap 8, FA p.364

What disease is a combined upper and lower motor neuron dysfunction? Cause?

Back 50

ALS (Lou Gehrig's dz): both UMN and LMN degeneration. NO SENSORY deficit.

Cause: defect in SOD 1 (superoxide dismutase: neutralizes superoixde, O2 radical, and copper serves as a cofactor for SOD)

Front 51

Chap 8, FA p.364

What is an example of dorsal column disease?

Back 51

Tabes dorsalis (tertiary syphilis): degeneration of the dorsal roots of dorsal columns = impaired proprioception, locomotor ataxia (no jt or m. position sense) = positive Romberg sign!!!

Also has absence of DTR's

Front 52

Chap 8, FA p.364

What sign signifies dorsal column disease?

Back 52

Positive Romberg sign

Front 53

Chap 8, FA p.364

What are four things associated with tabes dorsalis that aren't from the direct problem with the dorsal column?

Back 53

Tabes dorsalis (tertiary syphilis)
1. Charcot joints
2. shooting (lighting) pain
3. argyll robertson pupils (reactive to accomidation but not to light)
4. absence of DTR's

Front 54

Chap 8, FA p.364

Give one example of a spinal cord hemisection lesion (one half of the spinal cord is damaged):

What are the five features of this syndrome?

What happens if this lesion occurs above T1?

Back 54

Brown-Sequard syndrome:
1. ipsilateral UMN signs (corticospinal tract) - BELOW LESION
2. ipsilateral loss of vibration, proprioception sense (dorsal column) BELOW LESION
3. Contralateral pain and temperature loss (spinothalamic tract) BELOW LESION
4. LMN signs at LEVEL OF LESION (paralysis, down)

If lesion occurs above T1, presents with Horner's syndrome.

Front 55

Chap 8, FA p.364

What happens in ventral artery occlusion?

What if this happens at t-2 or above?

Back 55

Ventral artery occulsion: everything is damaged except dorsal column and tract of Lissauer.

1. bilateral pyramidal signs (lateral corticospinal)below the lesion
2. bilateral loss of pain and temp below the lesion (lateral spinothalamic)
3. bilateral LMN signs (down) from ventral/anterior horn damage
4. bilateral damage to sacral parasympatheitc centers at S-2 and S-4 = loss of voluntary bladder and bowel control.

At or above T-2 = bilateral Horner's syndrome

Front 56

Chap 8, FA p.364

What neuropathy is associated with vitamin B12 deficiency?

Back 56

Vitamin B12: subacute combined degeneration - caused by megaloblastic anemia.

Damages:
1. Demyelination of dorsal columns: bilateral loss of tactile discrimination and position/vibration sense
2. demyel of lateral corticospinal tract: bilateral UMN pyramidal signs (up)
3. demyel of spinocerebellar tract: bilateral arm and leg dystaxia (clumpsy movement)

Front 57

Chap 8, FA p.364

Other than Vit B12 deficiency what else causes subacute combined degeneration?

Back 57

Friedreich's ataxia:

Damages:
1. Demyelination of dorsal columns: bilateral loss of tactile discrimination and position/vibration sense
2. demyel of lateral corticospinal tract: bilateral UMN pyramidal signs (up)
3. demyel of spinocerebellar tract: bilateral arm and leg dystaxia (clumpsy movement)

Front 58

Chap 8, FA p.364

Damages in Syringomyelia?

Where does it along the spine does it most commonly effect?

What malformation is most commonly present?

Back 58

Syringomyelia: an idiopathic central cavitation of the cervical cord

Damages:
1. crossing fibers of spinothalamic tract are damaged = bilateral loss of pain and temp
2. HY says: LMN lesion too

MC effects: C8-T1

MC malformation: Arnold-Chiari - cerebellar herniation into brainstem

Front 59

Chap 8

What is a prime example of a syndrome causing PNS lesions? Describe clinical findings

Back 59

Guillain-Barre: inflammation and demyelination of peripheral nerves and motor fibers of ventral roots (sensory less severe than motor), causing symmetric ascending muscle weakness beginning at distal lower extremities.

Facial diplegia in 50%

Autonomic can be affected: cardiac prob, HTN/hypoTN

Findings: elevated CSF protein (papiladema) with nL cell count (albuninocytologic dissociation)

Front 60

Chap 8, FA p.361

Cause and treatment of Guillain-Bairre?

Back 60

Guillain-Barre: inflammation and demyelination of peripheral n. and motor fibers caused by infections with herpesvius or Campylobacter jejuni, as well as caused by stress.

Respiratory support is critical until recovery
Hx: plamaparesis, IV immunoglobulins

Front 61

Chap 8, FA

What are the nerve lesions associated with multiple sclerosis?

Some of the signs? (3)

Back 61

MS: mostly white matter of cervical region is effected in a random asymetric pattern due to demyelination.

Some signs are scanning speech, intention tremor, and nystagmus.

Front 62

Chap 8, FA p.361

How does the prevelance of multiple sclerosis change?

Back 62

Increased MS prevalence with increased distance from the equator.

Front 63

Chap 8, FA p.361

What is the specific (cell-wise) degeneration involved in multiple sclerosis?

Back 63

MS: oligodendrocytes are lost (forming periventricular plaques) and causing reactive gliosis.

Axons are preserved!

Front 64

Chap 8, FA p.361

Are there any interesting CSF findings in MS?

Back 64

CSF in multiple sclerosis has increase in protein (IgG)

Front 65

Chap 8, FA p.361

What is the classic triad of signs in MS and what are five other possible symptoms?

Back 65

Triad: SIN
Scanning speech, Intention tremor, Nystagmus

Also: optic neuritis (sudden loss of vision), MLF syndrome (internuclear opthalmoplegia), hemiparesis, hemisensory symptoms, bladder/bowel incontience.
Color image 47

Front 66

Chap 8

Where is intervertebral disc herniation most commonly seen?

Back 66

At the L4-L5 or L5-S1 segments (90%)

Front 67

Chap 8

What is does "intervertebral disc herniation" consist of?

Back 67

Consists of prolapse (or herniation) or the nucleus pulposus through the defective anulus fibrosus and into the vertebral canal.

The nucleus pulposus impinges on the spinal roots, resulting in spinal root symptoms (paresthesia, pain, sensory loss, hyporeflexia, muscle weakness)

Front 68

Chap 8

What is cauda equina syndrome?

Back 68

Cauda equina syndrome: involves spinal roots L3-down to end.
Results usually from a nerve root tumor.

Signs/symptoms:
severe radicular unilateral pain
saddle-shapped sensory distribution, unilateral
unilateral m. atrophy
Absent quadriceps (L3) and ankle jerk reflex (S1)
incontinence
onset gradual and unilateral

Front 69

Chap 8

What is conus medullaris syndrome?

Back 69

Conus medullaris: results from a intramedullary tumor (ependymoma)
1. Pain bilateral and not severe
2. sensory distribution in saddle-shaped area
3. unilateral m. atrophy
4. quadreceps and ankle jerk reflexes normal
5. incontinence
6. onset sudden and bilateral
(compare to cauda equina syndrome)

Front 70

Chap 8, FA p.361

Name five demyelinating/dysmyelinating diseases:

Back 70

1. MS
2. Progressive multifocal leukoencephalopathy: assoc with JC virus and seen in AIDS patients
3. Acute disseminated (post infectious) encephalopathy
4. Metachromatic leukodystrophy (a lysosomal storage dz)
5. Guillain-Barre syndrome (postinfectious)

Front 71

Chap 8: FA p.361

What is the treatment for MS?

Back 71

Hx: beta-interferon or immunosuppressant therapy

Front 72

Chap 8: FA p.361

Most common age and race for MS?

Back 72

Age: 20-30's
Race: white

Front 73

Chap 8: FA p.360

What are the symptoms of polio?

Back 73

Polio:
Malaise
Headache
Fever
Nausea
Abdominal pain
Sore throat
Signs of LMN lesion (down)

Front 74

Chap 8: FA p.360

What are the lab findings in a pt with polio?

Where is virus recovered from

Back 74

Polio:
CSF with lymphocytic pleocytosis with slight elevation of protein.

Virus is recovered from stool or throat culture

Front 75

Chap 9

What three things does the brainstem contain?

Back 75

Medulla
Pons
Midbrain

Front 76

Chap 9

Where does the brainstem receive blood from and what CN's run through it?

Back 76

Brainstem
Blood: verebrobasilar system

CN: 3-12 (except the spinal part of CN 11)

Front 77

Chap 9

What are the medial and lateral structures in the medulla?

Back 77

Medial
1. hypoglossal nucleus of CN 12
2. medial lemniscus (crossed fiibers from the gracile and cuneate nuclei)
3. the pyramid of corticospinal tract
Lateral:
1. nucleus ambiguus (CN 9, 10, 11)
2. vestibular nuclei (CN 8)
3. Inferior cerebellar peduncle: houses dorsal spinocerebellar, cuneocerebllar, and olivocerebellar tracts
4. lateral spinothalamic tract
5. spinal trigeminal nucleus (tract of CN 5)

Front 78

Chap 9

What are the medial structures of the pons?

Back 78

Pons medial structures:
1. medial longitudinal fasciculus
2. abducens nucleus of CN 6 (underlies facial colliculus)
3. genu (internal) of CN 7 (underlies facial n.)
4. abducent fibers of CN 6
5. medial lemniscus
6. coriticospinal tract (in the base of the pons)

Front 79

Chap 9

What are the lateral structures of the pons?

Back 79

Lateral structures of the pons:
1. facial nucleus (CN 7)
2. facial nerve fibers
3. spinal trigeminal nucleus and tract (CN 5)
4. lateral spinothalamic tract (spinal lemniscus)
5. vestibular nuclei of CN 8
6. cochlear nuclei of CN 8

Front 80

Chap 9

What are the 9 structures of the midbrain?

Back 80

Midbrain
1. cerebral aqueduct
2. oculomotor nucleus (CN III)
3. medial longitudinal fasciculus (MLF)
4. red nucleus
5. substantia nigra
6. medial lemniscus
7. lateral spinothalamic tract (spinal lemniscus)
8. superior colliculi
9. crus cerebri: where corticospinal tract runs through.

Front 81

Chap 10:

What does the trigeminal nerve do?

Back 81

Trigeminal nerve system:
provides sensory innvervation to the face, oral cavity, and supratentorial dura through somatic afferent (GSA) fiber.

It also innervates the muscles of mastication through special visceral efferent fibers (SVE)

Front 82

Chap 10

What type of cells does the trigeminal ganglion house?

Back 82

Pseudounipolar ganglion cells

Front 83

Chap 10

What does V1 of the trigeminal system do?

Back 83

V1: Opthalmic nerve
In the cavernous sinus and enters orbit through superior orbital fissure and innervates the forehead, nose, cornea, and upper eyelid.
It mediates the afferent limb of the corneal reflex.

Front 84

Chap 10

What does V2 of the trigeminal system do?

Back 84

V2: Maxillary nerve
Runs through the cavernous sinus and innervates the upper lip, cheek, lower eyelid, temple, nose, pharynx, gums, teeth

It exits the skull through the foramen rotundum.

Front 85

Chap 10

What does V3 of the trigeminal system do?

Back 85

V3: Mandibular nerve
It does not run through the cavernous sinus.
It has a sensory component (GSA) that innervates the lower lip and chin, temple, floor of mouth, and anterior 2/3 of tongue.

It also has a motor (SVE) component that runs through the forament ovale to innervate the m. of mastication, mylohyoid, ant. belly of digastric, tensores tympano, lateral/medial pterygoids.

It exits the skull through the foramen ovale.

Front 86

Chap 10

What is tic douloureux?
What age is MC?

Back 86

Trigeminal neuralgia:
characterized by recurrent paroxysms of sharp, stabbing pain in one or more branches of the trigeminal nerve on one side of the face.

Age: >50yo

Front 87

Chap 10

What is the DOC for trigeminal neuralgia?

Back 87

Carbamazepine

Front 88

Chap 10

What non-cranial nerve fibers run through the cavernous sinus?

Back 88

Post-ganglionic sympathetic fibers

Front 89

Chap 11

What is the fetal derivation of the auditory system?

Back 89

Auditory system is formed from the thickening of the ectoderm which forms the otic vesicle and otic placode.

Front 90

Chap 11

Describe the path from the ears to the brain? (Auditory system)

Back 90

sound stimulates hair cells of the Organ of Corti --> this activates bipolar cells of the spiral ganglion --> cochlear nerve --> cochler nuclei --> superior olivary nucleus --> trapezoid body (in pons) --> lateral lemniscus --> inferior colliculus --> medial geniculate body --> primary auditory cortex (Brodman 41, 42)

Front 91

Chap 10

What causes CONDUCTION deafness? (3 examples)

Back 91

Conduction deafness:
caused by interruption of the passage of sound waves through the external or middle ear
(obstruction, otosclerosis, otitis media)

Front 92

Chap 10

What causes NERVE deafness? (not conduction)

What kind of sound loss does this involve?

Back 92

Nerve deafness is caused by a problem with the cochlear nerve (or cochlea, or central auditory connections).

It is usually caused by presbycussis that results from degeneration of the organ of Corti = = high frequency sound loss.

Front 93

Chap 10

What is Weber's test?

Back 93

Weber's test: putting tuning fork on the vertex of the skull.

NL: pt hears equally on both sides
Unilateral conduction deafness: hears the vibration more loudly in affected ear
Unilateral partial nerve deafness: hears the vibration more loudly in the normal ear

Front 94

Chap 10

What is the Renne test? What does it do?

Back 94

Renne test: compares air and bone conduction. It is performed by placing a vibrating tuning fork on the mastoid process until the vibration is not longer heard, then fork is held in from of ear.

nL: Pt hears the vibration in the air after bone conduction stops
Unilateral conduction deafness: does not hear the vibration in the air
Unilateral partial nerve deafness: does hear the vibration in the air