Surgery Flashcards
1
Q
Anatomy and Physiology of Facial Nerve
A
- Special Visceral Afferent Fibers
- Sense of Taste on Anterior 2/3 of Tongue
- Via the Lingual and Chorda Tympani Nerves
- Geniculate Ganglion
- Nervus Intermedius to the Tractus Solitarius
- General Visceral Afferent Fibers
- Controversial
- Skin of the Concha and Auricle
- Special Visceral Efferent Fibers
- Stapedius Muscle
- Auricular Muscles
- Posterior Belly of Digastric Muscle
- Stylohyoid Muscle
- Platysma Muscles
- Superficial Facial Muscles
- General Visceral Efferent Fibers
- Parasympathetic System
- Greater Superficial Petrosal Nerve
- Lesser Petrosal Nerve
- Chorda Tympani Nerve → Lingual Nerve
- Parasympathetic System
2
Q
Pathophysiology of Nerve Injury
A
- Neurapraxia - Loss of Axoplasm Flow
- Axonotmesis - Wallerian Degeneration w/ the Preservation of Endoneural Sheaths
- Neurotmesis - Wallerian Degeneration + Loss of Endoneural Tubules
- Sunderland’s Five Levels of Neural Injury
- First Degree - Neurapraxia
- Second Degree - Axonotmesis
- Third Degree - Neurotmesis w/ Loss of Endoneurium
- Fourth Degree - Neurotmesis w/ Loss of Endoneurium and Perineurium
- Fifth Degree - Neurotmesis w/ Loss of Endo, Peri, and Epineurium
3
Q
Classification of Recovery From Facial Paralysis
A
- Grade I - Normal
- Grade II - Slight Weakness
- Grade III - Obvious, but not disfiguring difference b/t the two sides, Complete closure of eye w/ effort
- Grade IV - Obvious weakness and/or disfiguring asymmetry, Incomplete closure of eye
- Grade V - Slight Movement
- Grade VI - Total Paralysis
4
Q
Differential Diagnosis of Facial Paralysis
A
- Infection
- Bell’s Palsy
- Herpes Zoster Oticus
- Otitis Media/Mastoiditis
- Malignant Otitis Externa
- Tuberculosis
- Lyme Dz
- Acquired immunodeficiency Syndrome
- Infectious Mononucleosis
- Trauma
- Temporal Bone Fracture
- Birth Trauma
- Facial Contusions/Lacerations
- Penetrating Wounds
- Iatrogenic Injury
- Neoplasia
- Cholesteatoma
- Glomus Jugulare or Tympanicum
- Carcinoma
- Facial Neuroma
- Schwannoma
- Meningioma
- Leukemia
- Histiocytoses
- Rhabdomyosarcoma
- Congenital
- Compression Injury
- Mobius Syndrome
- Lower Lip Paralysis
- Idiopathic
- Recurrent Facial Palsy
- Melkersson-Rosenthal Syndrome
- Metabolic and Systemic
- Sarcoidosis
- Guillain-Barre Syndrome
- Autoimmune Disorders
5
Q
Evaluation of Facial Paralysis
A
- Hx
- Onset
- Duration
- Rate of Progression
- Recurrent or Familial
- Associated Symptoms
- Major Medical Illness/Major Surgery
- Physical Exam
- Microscopic Otoscopy
- URT Examination
- Cranial Nerve Assessment
- Palpation of Parotid Gland and Neck
- Neurologic
- Cerebellar Signs
- Motor
- Facial Nerve Function
- Complete vs. Incomplete (Paresis)
- Segmental vs. Uniform
- Unilateral vs. Bilateral
- Lab Studies
- Audiometry
- Electrophysiology Tests
- Nerve Excitability Test
- Maximal Stim Test
- Electroneurography
- Electromyography
- Radiographic Studies
- CT
- MRI
- Possible Additional Studies
- CBC w/ Differential
- Erythrocyte Sedimentation Rate
- Serum Antibody
- Serum Antinuclear
- Rheumatoid Factor
- CXR
- Lumbar Puncture w/ CSF Assay
- Topographic Testing
- Includes Schirmer Test, Stapedial Reflex, Electrogustometry, and Salivary Flow
- NOW considered “OBSOLETE”
6
Q
Electrophysiologic Tests
A
- NET, MST, and ENOG provide the most accurate information w/in the first 3 weeks
- EMG cannot differentiate b/t a total neurapraxia vs. completely degenerated nerve in acute phase
- Paresis does NOT warrant electrophysiologic tests
7
Q
Bell Palsy
A
- ACUTE onset w/ limited duration
- Diagnosis of exclusion
- 1/3 develop only a paresis w/ >95% recovery
- 2/3 w/ paralysis w/ 85% havings some return of facial tone w/in 3 weeks
- 71% of all pts achieve H-B grade 1
- ENOG w/ 90% degeneration in the first 2 weeks recover to H-B grade I or II in only 50% of pts
- Maximal nerve injury occurs at meatal foramen
- Decompression is directed at the labyrinthine portion
- Treatment Regimen
- Prednisone 1 mg/kg/day in divided doses and tapered over 7-10 days
- Acyclovir 2000 mg/day in 5 doses for 7 days
- Delay of more than 3 days precludes any additional benefit
*
8
Q
Herpes Zoster Oticus
A
- Ramsay Hunt Syndrome
- Facial Paralysis, Ear Pain, and Vesicular Eruption
- Pain precedes paralysis by a few days
- SNHL and vestibular dysfunction in 20%
- Poorer prognosis for spontaneous recovery than Bell Palsy
- Management
- Steroid Taper
- Valacyclovir 1000 mg TID x 7days
- Consider IV Doses
9
Q
Otitis Media
A
- Incidence of facial palsy in AOM about 1:20,000
- COM w/ facial paralysis is more ominous
- Aural toilet and antibiotics
- Myringotomy and Tube
- CT Scan
- Consider Tympanomastoidectomy w/ decompression of the mastoid/tympanic facial nerve
- Incision of Epineurium not recommended
10
Q
Trauma Related Facial Paralysis
A
- Temporal bone fractures are categorized according to otic capsule involvement
- Less than 5% involve otic capsule
- Facial nerve injury occurs in 50% of all otic capsule fractures
11
Q
Eye Care Related to Facial Paralysis
A
- Corneal desiccation = Most Common Complication
- Warn pt about itching redness, FB sensation, and visual blurring
- Prevention = lubricants, tape or moisture chambers, and avoidance of wind, vents, and fans
- Consider gold weight implants, canthoplasty, tarsorrhaphy, and upper eyelid springs
12
Q
Swallowing Phases
A
- Preparatory and Oral Phase
- Voluntary Phase
- Pharyngeal Phase
- Reflexive Phase; < 1 second in normal pts
- Esophageal Phase
- Fluid is passive, solid is active
13
Q
Management of Dysphagia
A
- Treat underlying cause
- Iron, pyridostigmine, benzotropine, abx
- Reflux regimen
- Aspiration pneumonia
- Botox injections
- Swallowing rehabilitation
- Change food consistency
- Supraglottic swallow
- Mendelsohn maneuver
- Surgery
- Esophageal dilation
- Cricopharyngeal myotomy
- G or J tube
- Vocal fold medialization
- Tracheotomy
- Laryngectomy
14
Q
Upper Esophageal Sphincter
A
- Cricopharyngeus muscle
- Tonic closure prevents reflux, aspiration, and regurgitation
- Relaxes during pharyngeal phase
15
Q
Lower Esophageal Sphincter
A
- Normal tone: 10-40 mmHg
- Achalasia >40
- Scleroderma <10
- Physiologic Sphincter (Aided by Diaphragm)
- Hiatal Hernia = LES Above Diaphragm
16
Q
GERD/LPR Diagnosis
A
- May begin antireflux regimen from hx
- Flex Laryngoscopy
- Barium Swallow
- 24-hour pH Probe = Gold Standard (but not practical)
- Esophagoscopy/TNE
17
Q
Achalasia
A
- Degeneration of Auerbach’s Plexus
- Aperistalsis and Increased LES Pressure
- Increased Risk of Esophageal Cancer
- Treatment
- Dilation
- “Wash” meals down w/ fluids
