Procedures and Imaging Flashcards
Purpose of X-ray in ENT?
- detect sinusitis (can help confirm)
- detect fluid in sinuses
- detect polyps
Indications for X-ray?
- pain and pressure in face, especially lowering head
- when clinical sxs need supportive evidence to make the dx
Different types of X-ray for ENT?
- water’s view, waters projection: posterioranterior radiographic view of the skull made with orbitomeatal line at angle of 37 degrees from the plane of the film, to show the orbits and maxillary sinuses
- maxillary sinus: a frontal view of maxillary sinuses, orbits. nasal structures. and zygomas, permits direct comparison of sides
What can you detect on x-ray?
- epiglottitis
- croup (steeple sign)
- retropharyngeal abscess (imaging test of choie is CT scan of neck)
When is CT use preferred?
- good for bone involvement, better than x-ray
- sensitive to bone destruction: trauma, infection
- sensitive to inflammatory changes: retropharyngeal abscess. ludwig’s angina
- preferable to MRI for scanning larynx for neck nodes, tumor volume, cartilage sclerosis, and destruction
CT of sinuses is useful for?
- gives further info about certain tumors of nasal cavity and sinuses
- can provide impt info about sinus and nasal obstruction
- able to detect sinuses that are filled with fluid
- can detect if sinus membranes are thickened
- assist with dx of sinusitis
when is a MRI useful?
- valuable in demonstrating soft tissue involvement
- sensitive enough to evaluate mucous membranes
- can distinguish tumor from inflammation and inspissated mucus
- useful if malignancy suspected (acoustic neuroma)
Indications for throat swab and culture?
- sore throat
- fever of unknown origin
- chronic carriers with recurrent infection
Indications for nose swab and culture?
- nasal or sinus infections
- carriers of pathogenic bacteria
What pathogens are identified by throat cultures?
- Bordatella pertussis
- streptococci, esp b-hemolytic strep
- meningococci, corynebacterium diptheriae
Nasal cultures are used to ID what bacteria?
- staph aureus
- MRSA
nasopharyngeal swabs are used to ID what bacteria?
- H-flu
- RSV
- influenza
- pertussis
Difference b/t nasal and nasopharyngeal swab?
- nasopharyngeal: in deeper, more delicate swab that is flexible
Rapid strep test use?
- posterior pharyngeal swab
- has an antiserum against group A strep
- very accurate w/o cultures
- takes about 5 minutes to perform
- if negative, and sxs consistent with GAS, culture should be done
- culture will take at least 2 days
- if culture is negative, no strep infection exists
Diff methods of testing throat culture?
- diff media:
chocolate, strep-specific, other agar - may quickly gram stain bacteria and initiate therapy based on whether gm + (blue) or - (red).
Cerumen disimpaction method?
- if cerumen can be removed using curette or otoloop, this is safest method, and usually only mildly uncomfortable to pt
- Ear canal is much less sensitive along top compared to bottom
When shouldn’t you do ear irrigation on a pt?
- if pt has hx of ruptured TM or has FB such as insect in ear (possibility of having ruptured TM)
Tx of epistaxis?
- topical vasoconstrictors/analgesics
- direct pressure
- silver nitrate cautery
When should you use topical vasoconstrictors? Types?
- ongoing bleeding
use: - inhaled afrin
- cotton balls soaked in Epi and lidocaine
Direct pressure for epistaxis?
- tape 2 tongue blades together and leave in place for up to 20 minutes
Nasal cautery use? Method?
- after 20 min of direct pressure:
remove cotton balls, gently evacuate clot by suction or gentle nose blowing - inspect nare with nasal speculum
- if ongoing bleeding is seen apply a silver nitrate stick to site for 10 sec then roll it over surrounding area
(have to be able to see source of bleed) - don’t cauterize both sides of nasal septum at same time becuase of risk of septal perforation
- must be able to directly visualize the bleeding area
- apply abx ointment over cauterized area
Most cases of epistaxis occur where?
- anterior part of nose
Posterior nasal packing should be done by whom?
- experienced physician or ENT doc
Anterior nasal packing utensils?
- gauze: petroleum soaked
- commercial nasal tampon: rhino rocket, mercel
Nasal packing follow up? Result if packing too tight?
- f/u reqd w/in 24 hrs
- leave in place for 48 hrs usually
- may cause necrosis if packing too tight
- may develop sinusitis, otitis media, or TSS
Use of pneumatic otoscopy?
- normal light reflex from tympanic membrane provides info regarding middle ear fxn
- degree of mobility of TM using pneumatic otoscopy or tympanometry is more helpful
- movement is best visualized in posterosuperior quadrant of ear drum
Procedure of pneumatic otoscopy?
- insert otoscope far enoguh to create good seal, this prevents air leakage b/t speculum and ear canal wall
- gently squeeze bulb on otoscope to create positive pressure on tympanic membrane and observe degree of tympanic membrane mobility
- release bulb to create negative pressure on TM and observe degree of TM mobility
Interpretation of pneumatic otoscopy?
- increased mobility: may be caused by atrophy, previous perforation or tympanostomy tube
- absent or decreased mobility of TM may be caused by:
acute otitis media, scarring
What is audiometry?
- formal measurement of hearing
- it involves the presentation of tones or speech to each ear
- a range of frequencies is used, and the pt’s pattern of response is analyzed
- pt raise hands in response to sound or in case of children, CPA is used
- can also test speech recognition
- measurement is usually performed using an audiometer by an audiologist (non medical healthcare professional specializing in eval and rehab of people with hearing loss)
What is pure tone audiometry?
- hearing measured at frequencies varying from low (250 Hz) to high pitches (8000 Hz)
- Hearing Level is quantified relative to normal hearing in dbs, with higher numbers of dB indicating worse hearing
- the dB score isn’t really percent loss, but 100 db hearing loss is nearly equal to complete deafness for that particular frequency
- score of 0 is normal
- you can have scores less than 0, indicate better than average hearing
- PTA (pure tone average) is average of pure tone hearing thresholds at 500, 1000, and 2000 Hz
Purpose of Weber/Rinne test?
- to determine if hearing loss is caused by sensory problem (sensorineural hearing loss) or mechanical problem (conductive)
- tests should be done together
- Rinne should be done first
Results of Rinne?
- normal: AC will be greater than BC
- Test is mainly for conductive hearing loss
- if BC is greater than AC there is something that is blocking air conduction = conductive hearing loss
- if sensorineural hearing loss the AC and BC will be equally diminished and AC will be greater than BC still
- normal Rinne is +
- abnormal Rinne is -
Weber test results?
- normal is for pt to hear sound equally in both ears
- can’t determine if ear that heard sound best is normal or abnormal w/o Rinne test
- if Rinne was completely normal than there is SNHL in ear opp of where Weber was heard best
- if Rinne abnormal in same ear that weber lateralizes to then there is CHL in that ear
What does tympanometry measure?
- impedance of middle ear to sound
- uses airtight seal and microphone to deliver sound to ear canal
- amt of sound that is absorbed or reflected from middle ear is measured at microphone at normal, positive, and negative air pressures
When is tympanometry useful? What can it detect?
- useful in IDing middle ear effusions in children and it may also detect facial nerve paralysis and may diff sensory from neural hearing loss
- detects fluid in middle ear, negative middle ear pressure, disruption of ossicles, and otosclerosis
- can also detect abnormally stiff ear drums (often due to fluid behind them, scarring or otosclerosis) as well as abnormally floppy ear drums (hyper compliant) usually due to excessive clearing of ears
- can also be used to detect abnormal contractions of stapedius and tensor tympani muscles. This reqrs a machine that can run tympanogram over 30 sec, at single frequency, looking for blips in trace
How is tympanometry performed?
- soft proble placed in ear canal and small amt of pressure is applied
- instrument then measures movement of TM in responses to pressure changes
Results of tympanometry?
- result recorded in visual output, called tympanogram
- if there is fluid in middle ear, TM won’t vibrate properly and the line on tmypanogram will be flat
- if there is air in middle ear (normal) but the air is higher or lower pressure than the surrounding atm, the line on tympanogram will be shifted in position
What is vestibular caloric testing?
- used to test disorders of the ear or brainstem
- Part of ENG (electronystanography):
used in dx of BPPV, perilymph fistula, vestibular neuritis, gentamycin ototoxicity - may be useful in work up of dizzy pt
What happens when cold and warm water enters ear in vestibular caloric testing?
- cold water enters: ear and inner ear changes temp, should cause fast nystagmus - eyes should move away from cold water and slowly back
- warm water: eyes should move toward warm water and then slowly away
Use of ice water caloric test?
- can be used to confirm absence of brainstem fxn in comatose pt
- if eyes don’t move with instillation of ice water in ear canal, there is lack of brainstem fxn