OPEN ACCESS GUIDE TO AND HEARING AIDS FOR OTOLARYNGOLOGISTS

PNEUMATIC OTOSCOPY AND OTOSCOPY Tashneem Harris

Most problems can be very adequately bulbs should be changed periodi- assessed by clinical examination alone cally (after 20h use) as adequate viewing which includes otoscopy, pneumatic oto- requires >100 foot candles light. The scopy, otomicroscopy and clinical hearing handle contains the batteries, which may evaluation. be rechargeable.

Pneumatic otoscopy delivers both positive Ear Specula (Figure 2) and negative pressure through a pneumatic otoscope and allows one to gain infor- Several sizes of specula should be mation about the status of the available. Types of specula include: space by determining tympanic membrane Reusable ear specula: 2.5mm, 3mm, mobility. 4mm, and 5mm Single-use ear specula: 2.75mm and Otoscopy involves systematic inspection of 4.25mm the external and tympanic mem- SofSpecTM reusable specula have a brane with an otoscope. soft tip specially contoured for a pneumatic seal: 3mm, 5mm and 7mm

Pneumatic Otoscopy

Pneumatic otoscopy provides a dynamic assessment of the tympanic membrane and the middle ear and is a useful means to evaluate disease in the middle ear cleft.

Advantages are that are widely Figure 2a: Reusable ear specula available and cheap compared to the cost of . With appropriate train- ing and experience it is simple and easy to perform.

One requires a pneumatic otoscope (Figure 1), a selec- tion of ear specula that pro- Figure 2b: Single-use ear specula vide a tight seal with the ear canal, and an insufflator bulb.

Pneumatic Otoscope (Fig 1)

It must be fully charged or supplied with new batteries and the bulb (halogen / xenon) must be bright.

TM Figures 2c: SofSpec ear specula Figure 1: Pneumatic otoscope:

Note insufflation port on side of otoscope head

Insufflator bulb movement, but also the degree of mobility compared to the normal tympanic mem- The insufflator bulb is attached tightly to brane. the head of the otoscope by means a tube and a tip to avoid loss of an air seal Reasons for an immobile tympanic (Figure 3). membrane in response to pressure changes in the external canal include: Fluid (mucus, blood, pus, CSF) in the middle ear cavity Perforation of the tympanic membrane Adhesive media

Diagnostic applications of pneumatic otoscopy

1. with effusion (OME)

Pneumatic otoscopy is one of the principal diagnostic measures used to diagnose Figure 3: Insufflator bulb and tube OME; it may indicate OME even when the appearance of the gives no other indication of middle ear pathology. Mechanism of pneumatic otoscopy The American Academy of Family A normal tympanic membrane moves Physicians, American Academy of 1mm medially and laterally when pressure Otololaryngology-Head and Neck Surgery, in the external auditory canal is increased and American Academy of Pediatrics and reduced respectively. Subcommittee published evidence-based clinical practice guidelines related to diag- The degree of tympanic membrane nosing and managing OME in children. mobility depends on a number of factors The subcommittee strongly recommended including: that clinicians use pneumatic otoscopy as Presence of a middle ear effusion the primary diagnostic method. Tympano- Amount of effusion; tympanic mem- metry is recommended as an adjunct to brane mobility is one of the most im- confirm the diagnosis when the diagnosis portant otoscopic findings used to is uncertain.2 Otoscopy alone, without determine whether a middle ear effu- using of the pneumatic otoscope to test sion is present1 tympanic membrane mobility, is not Degree of alteration of negative or recommended. positive pressure in the middle ear space compared to an ambient state The Agency for Healthcare Research

Condition of the tympanic membrane Quality Evidence Report systematically e.g. thickening, atrophic areas, tym- reviewed the sensitivity, specificity, and panosclerosis or perforation. predictive values of eight methods to diagnose OME and used myringotomy as It is therefore important for clinicians not the gold standard.3 Meta-analyses revealed only to note the presence or absence of that pneumatic otoscopy and professional

2 tympanometry had the highest sensitivi- 4. Helps to assess tympanic membrane ties.3 Although professional tympanometry landmarks had the highest sensitivity, pneumatic otoscopy optimised both sensitivity and 5. Used in fistula test (Hennebert’s specificity.3 Pneumatic otoscopy is there- sign) fore useful in a setting where tympano- metry is not readily available. The A positive fistula test is marked by nystag- diagnostic accuracy of pneumatic otoscopy mus and when pneumatic otoscopy in OME has been shown in several studies is done. Clinical examples include the to be dependent on clinicians’ training and following: experience.4,5,6 One of the limitations With it suggests erosion mentioned in this review was that most of the labyrinth, most commonly of the studies fail to provide enough information lateral semicircular canal. Reports to assess the qualifications of testers show that this test is positive in 40- performing pneumatic otoscopy.3 50% of patients who have a fistula. A Pneumatic otoscopy therefore requires negative test therefore does not exclude appropriate training to optimise diagnos- a fistula 9, 10 tic accuracy. In trauma to the middle and inner ear it alerts one to the presence of a peri- 2. Acute otitis media lymphatic fistula With superior semicircular canal dehis- Diagnosing acute otitis media can be quite cence syndrome, pressure changes in- challenging, particularly in young children. duced in the external auditory canal Diagnostic criteria include a rapid onset of evoke stereotyped eye movements that symptoms, symptoms and signs of middle align in the plane of the dehiscent ear inflammation as well as the presence of semicircular canal.11 It thereby helps to 7 a purulent middle ear effusion. While distinguish associated with otoscopy detects inflammation (erythema, superior semicircular canal dehiscence bulging of tympanic membrane, cloudi- syndrome from other conditions such ness, opacification and loss of landmarks), as detection of reduced movement of the tympanic membrane on pneumatic otos- 6. Brown’s sign copy is the key to diagnosing a middle ear 8 effusion. Otoscopic examination of a middle ear paraganglioma (glomus tympanicum) may 3. Tympanic membrane retraction reveal a reddish-blue pulsatile mass behind an intact tympanic membrane. When When the tympanic membrane is retracted application of positive pressure with a due to negative middle ear pressure, it is pneumatic otoscope causes the mass to often flaccid and hypermobile. Movement blanch it is referred to as "Brown's sign" It of the tympanic membrane is therefore occurs in a third of glomus tympanicum exaggerated when negative pressure is cases.12 applied i.e. when the bulb is released rather than when the bulb is compressed. Pneumatic otoscopy helps one to identify such a retracted tympanic membrane and also to differentiate retraction from a large central perforation.

3 Technique of Pneumatic Otoscopy

There are a number of prerequisites to do the procedure correctly:

Test the pneumatic otoscope for air leaks

1. Attach an aural speculum to the otoscope and occlude the end of the speculum with the tip of an index finger Figure 4: Holding the otoscope and 2. Attach the insufflator bulb by its bulb rubber/plastic tube to the otoscope head Slightly compress the pneumatic 3. Occlude the open end of the oto- bulb, and then insert the aural scope and apply positive pressure speculum into the ear canal by squeezing the bulb 4. Listen for an air leak at the junction The reason why the pneumatic bulb between the otoscope and the aural should be slightly compressed before speculum or of the rubber/plastic insertion, and then released, is to tubing that connects the otoscope generate negative pressure in the ear with the pneumatic bulb, or at the canal. Application of gentle negative joint between the lens and the pressure in pneumatic otoscopy is often otoscope head neglected and is important for the following reasons:

Snuggly fitting aural speculum 1. OME is often associated with a negative middle ear pressure, which Another common site for a leak is at can be more accurately assessed by the junction between the tip of the releasing the already-compressed aural speculum and the skin of the ear bulb canal. The pressurised air then leaks 2. Pneumatic otoscopy allows one to out of the external auditory meatus and differentiate between a retracted the tympanic membrane appears to be tympanic membrane which is not immobile or poorly mobile. This may adherent to any middle ear structure cause the examiner to over-look a and therefore moves laterally with middle ear effusion the application of negative pres- 1. For this reason it is important to use sure; and adhesive otitis media the largest aural speculum to ob- where the TM is adherent to a tain a good seal between the specu- middle ear structure and therefore lum and the external ear canal remains immobile 2. If a leak still persists then apply gentle tragal pressure to achieve an Reseal the system, if necessary by airtight seal around the speculum compressing the tragus against the ear canal opening Correctly hold the otoscope and bulb (Figure 4) Once an airtight seal has been secured, release the compression on

4 the bulb: This causes the tympanic hand and when examining the left ear the membrane to move laterally otoscope is held with the physician’s left hand. The bulb is gently, not firmly, squeezed: A common error is to apply excessive amounts of compression to the pneumatic bulb

Negative pressure is followed by positive pressure and this is repeated several times

Otoscopy Technique

Before performing otoscopy, always do a general examination of the ear. Inspect the pinna and postauricular skin noting any scars, erythema and deformity. Both must be examined; if the disease affects only one ear, then the normal ear is examined first. This allows you to appre- ciate the normal anatomical variation for Figure 5: Holding a child that particular patient. Inspect the entrance to the ear canal to ensure that there is no Find the largest speculum, which com- debris or wax which might interfere with fortably fits into the ear canal in order to the examination. The ear canal must be maximise the amount of light passing into cleared of all debris. A common mistake is the ear canal and to optimise the view of to peek through a small hole in the the tympanic membrane. Rule of thumb: cerumen, thus only visualising a tiny part adults size 4-5mm, children 3-4mm and of the tympanic membrane. 2,5mm for infants.

When examining a child the head and the Switch on the otoscope by pressing the body need to be gently immobilised coloured button and turning it clockwise. (Figure 5). This is best achieved with the Hold the otoscope close to its head be- child seated in the parent’s lap. The parent tween the thumb and the first two fingers, restrains the child by placing one hand much like holding a pencil (Figure 6). firmly on the child’s forehead and holding the side of the child’s head against the The little finger of the hand holding the chest, while the other arm is placed firmly otoscope is placed firmly against the around the child’s body and both arms. It patient’s cheek and used as a fulcrum may help to show infants the otoscope and (Figure 7). In this way the hand moves in allow them to hold the otoscope before unison with the patient’s head, avoiding examining them so as to reassure them that injury should the patient move unexpec- the examination will not be painful. tedly.

When examining the patient’s right ear, the otoscope is held with the physician’s right

5 depth to adequately visualise the tympanic membrane.

Figure 6: Holding the otoscope

Figure 8: Gripping otoscope like a pistol

The outer third of the external ear canal (cartilaginous portion) has hair bearing skin, whereas the inner two-thirds is hair- Figure 7: Little finger used as a fulcrum less and very sensitive. To facilitate a non- traumatic insertion the speculum should Another technique of holding the otoscope not be inserted beyond the hair bearing is by gripping it like a pistol, with the skin of the external ear canal. otoscope held almost vertically in the palm of the hand (Figure 8). The dorsal aspect Now look through the magnifying lens and of the patient’s index finger is held against through the speculum. To view the entire the patient’s cheek. ear canal and tympanic membrane the position of the speculum often has to be The speculum is gently inserted into the adjusted to change the line of vision. external ear canal. The external ear canal is crooked; to straighten the canal, use the Assessing external auditory canal free hand to gently pull the pinna outward and downward in infants and upward and The external ear canal should be routinely posteriorly in older children and adults. In examined for: infants or children with very stenotic ear Tenderness on pulling the auricle, canals (e.g. Down’s syndrome) it helps to which indicates insert the speculum by gently rotating the Infection: swollen and narrow, mois- speculum in the external auditory canal so ture, pus that the speculum is inserted at the correct Bony narrowing Debris

6 Assessing tympanic membrane

The normal tympanic membrane is pinkish-gray in colour, fairly trans- lucent and mobile (Figure 9) Note the colour, translucency and position of the tympanic membrane and assess its mobility by pneumatic otoscopy Assess the landmarks of the tympanic membrane. The malleus normally lies in a slightly oblique position. Identify the pars tensa with its cone of light in the anteroinferior quadrant of the Figure 10: Otitis media with effu- tympanic membrane, the handle and sion (OME) lateral process of malleus, the anterior and posterior folds of the pars flaccida 2. Red (erythema): suggests acute and position of the malleus handle. otitis media; however crying in infants and young children can also cause reddening 3. Dull/loss of light reflex: otitis PF media with effusion or acute otitis media AMF 4. White plaques: LP 5. Translucency: A normal tympanic PMF membrane is translucent. A trans- parent tympanic membrane is MH typically seen in a very atrophic Light cone tympanic membrane due to loss of PT the fibrous layer

Figure 9: Otoscopic appearance of normal (right) tympanic membrane and its land- CT marks: Pars flaccida (PF); anterior mal- ISJ leolar fold (AMF); lateral process of mal- leus (LP); posterior malleolar fold (PMF); malleus handle (MH); pars tensa (PT)

Colour and appearance 1. Yellow (amber): serous fluid be- hind TM suggestive of otitis media with effusion (OME) (Figure 10) Figure 11: Chorda tympani (CT)

and incudostapedial joint ISJ) visible through a very atrophic TM

7 6. Landmarks: Absent landmarks oc- cur in acute otitis media 7. Perforation: Size and location; anterior/poste- rior quadrant (Figure 12) Condition of middle ear mucosa (granular, polypoid)

Figure 13: Pars tensa and pars flaccida retractions with bony erosion – cholesteatoma case

References

1. Karma PH, Penttila MA, Sipila MM, Figure 12: Small anterior inferior Kataja MJ. Otoscopic diagnosis of quadrant perforation middle ear effusion in acute and non- acute otitis media. I. The value of 8. Note the position of the handle of different otoscopic findings. Int J malleus (neutral/medialised) Pediatr Otolaryngol.1989;17:37– 49 9. Squamous debris: A cholesteatoma 2. Rosenfeld RM, Culpepper L, Doyle is a collection of keratinising squa- KJ, Grundfast KM, Hoberman A, mous epithelium in the middle ear Kenna MA, Lieberthal AS, Mahoney cleft associated with bone resorp- M, Wahl RA, Woods CR Jr, Yawn B; tion. It may be congenital or ac- American Academy of Pediatrics quired. Acquired Subcommittee on Otitis Media with most commonly originate from a Effusion; American Academy of large posterosuperior perforation or Family Physicians; American Academy attic perforation. There is usually a of Otolaryngology-Head and Neck history of chronic infection with Surgery. Clinical practice guideline: discharge Otitis media with effusion. Otolaryngol 10. Position of tympanic membrane Head Neck Surg. 2004 ;130(5 Suppl): Bulging suggests acute otitis S95-118 media 3. Shekelle P et al. Diagnosis, natural Retraction suggests eustachian history, and late effects of otitis media tube or middle ear mucosal dys- with effusion. Evid Rep Technol function Assess. 2002 ;55:1-5 11. If retracted: Is pars flaccida or the 4. Pichichero ME, Poole MD. Assessing pars tensa retracted? (Figure 13) diagnostic accuracy and tympanocen- tesis skills in the management of otitis media. Arch Pediatr Adolesc Med. 2001;155:1137-42

8 5. Pichichero ME, Poole MD. Compari- Author son of performance by otolaryngolo- gists, pediatricians, and general prac- Tashneem Harris MBChB, FCORL, tioners on an otoendoscopic diagnostic MMed (Otol) video examination. Int J Pediatric ENT Specialist Otorhinolaryngol. 2005;69(3):361-6 Division of Otolaryngology 6. Adams MT, et al. Prospective com- University of Cape Town parison of handheld pneumatic otos- Cape Town, South Africa copy, binocular microscopy, and tym- [email protected] panometry in identifying middle ear effusions in children. Int J Pediatr Editors Otorhinolaryngol. 2010; 74(10):1140-3 7. Ramakrishnan K, Sparks RA, Berryhill Johan Fagan MBChB, FCORL, MMed WE. Diagnosis and treatment of otitis Professor and Chairman media. Am Fam Physician. 2007; Division of Otolaryngology 76(11):1650-8 University of Cape Town 8. Subcommittee on Management of Cape Town, South Africa Acute Otitis Media. Diagnosis and [email protected] Management of Acute Otitis Media. Pediatrics. 2004;(113):1451-5 Claude Laurent, MD, PhD 9. Busaba NY. Clinical presentation and Professor in ENT management of labyrinthine fistula ENT Unit caused by chronic otitis media. Ann Department of Clinical Science Otol Rhinol Laryngol. 1999;108(5): University of Umeå 435-9 Umeå, Sweden 10. Parisier SC, Edelstein DR, Han JC, [email protected] Weiss MH. Management of labyrin- thine fistulas caused by cholesteatoma. De Wet Swanepoel PhD Otolaryngol Head Neck Surg. Associate Professor 1991;104(1):110-5 Department of Communication Pathology 11. Shuman AG, Rizvi SS, Pirouet CW, University of Pretoria Heidenreich KD. Hennebert's sign in Pretoria, South Africa superior semicircular canal dehiscence [email protected] syndrome: a video case report. Laryngoscope. 2012; 122(2):412-4 12. Forest JA 3rd, Jackson CG, McGrew OPEN ACCESS GUIDE TO BM. Long-term control of surgically AUDIOLOGY & HEARING AIDS treated glomus tympanicum tumors. Otol Neurotol. 2001;22(2):232-6 FOR OTOLARYNGOLOGISTS www.entdev.uct.ac.za

The Open Access Atlas of Otolaryngology, Head & Neck Operative Surgery by Johan Fagan (Editor) [email protected] is licensed under a Creative Commons Attribution - Non-Commercial 3.0 Unported License

9