Symptoms: Bilateral Mixed Hearing Loss

Abstract

A 22-year-old patient with hearing loss beginning at age 12 presented to the clinic for hearing aid clearance. She reports bilateral hearing loss more severe on the right with aural fullness and occasional otalgia. She additionally endorses allergic rhinitis and recurrent otitis media. On exam, there were multiple pre-auricular pits present. On microscopic exam of the ear the right ear showed mucoid effusion and pale middle ear mucosa on the right with a normal exam of the left ear. Tympanic membranes were otherwise intact bilaterally except for some thickening observed on the right (see Figure 1). Tympanogram was flat on the right and normal on left. Her audiogram is shown in Figure 2.Figure 1: Image of patient’s tympanic membrane showing some thickening of the tympanic membrane. Clinical Consultation, bilateral mixed hearing loss, congenital cholesteatoma.Figure 2: Image of patient’s audiogram. Clinical Consultation, bilateral mixed hearing loss, congenital cholesteatoma.Figure 3: Axial (horizontal) CT of right temporal bone showing the middle ear opacification indicating fluid or soft tissue. Clinical Consultation, bilateral mixed hearing loss, congenital cholesteatoma.Figure 4: Coronal (parallel to the face) CT of right temporal bone showing the entire middle ear and mastoid is opacified indicating fluid or soft tissue. Clinical Consultation, bilateral mixed hearing loss, congenital cholesteatoma.Figure 5: Axial (horizontal) T2-weighted MRI showing hyperintensity (bright white) in middle ear and mastoid indicating either fluid or cholesteatoma. Clinical Consultation, bilateral mixed hearing loss, congenital cholesteatoma.Figure 6: Coronal (parallel to the face) HASTE sequence MRI showing hyperintensity (brightness) in middle ear indicating cholesteatoma presence. Clinical Consultation, bilateral mixed hearing loss, congenital cholesteatoma.Diagnosis: Congenital Cholesteatoma Madelyn Frank, BA; Karen Tawk, MD; Mehdi Abouzari, MD, PhD; and Hamid R. Djalilian, MD A 22-year-old presenting with hearing loss since childhood can have a range of etiologies including congenital, autoimmune, infectious, or neoplastic. A thorough diagnostic workup should include a detailed history, physical exam, audiological evaluation, and imaging. This patient’s preauricular pits, otorrhea, otalgia, and aural fullness in addition to bilateral asymmetric mixed hearing loss invite a wide differential diagnosis. Preauricular pits and sinuses are a result of incomplete fusion of the first and second brachial arch that does not usually result in middle or inner ear abnormality. In patients with bilateral preauricular pits, an evaluation for brachio-oto-renal spectrum disorders (BORSD) is warranted. While patients typically present in childhood, health care access challenges can lead to presentation as an adult. BORSD is a syndrome with variable phenotypes consisting of second brachial arch malformations, otologic abnormalities, and renal pathology. Brachial cleft cysts present as a palpable mass under the sternocleidomastoid and sinus tracts typically appear as a pinpoint opening anterior to the sternocleidomastoid. Hearing loss is present in 95% of patients and is most frequently mixed and bilateral. 1 The external ear may have atresia or stenosis. The middle ear may be small or malformed with fixed or displaced ossicles. Abnormalities of the inner ear can include hypoplasia of the semicircular canal or cochlea, or enlargement of the cochlear and vestibular aqueducts. Renal features are varied including agenesis, uretero-pelvic junction obstruction, and calyceal diverticulum. Presence of renal pathology is not essential to diagnosis, however renal ultrasound and renal function testing should be included when suspecting BORSD. Of note, if the patient has a known affected family member, only one major criteria is needed to diagnose. There is an autosomal dominant hereditary pattern with 100% penetrance; although, presentation may differ within families. Variants have been identified in the genes EYA1, SIX1, SIX5, and SALL1 and a confirmatory multigene panel can be performed. Treatment is aimed at resolving the individual’s manifestations including hearing aids, brachial cyst repair, and renal surveillance. For patients with frequent discharge or recurrent infections of preauricular pits, surgical excision of the sinus can be performed. Unlike congenital etiologies, autoimmune causes of hearing loss are potentially reversible if diagnosed early in the disease course. 2 Granulomatosis with polyangiitis (GPA) is a small vessel vasculitis that can present initially as hearing loss. 3 The onset is typically in patients ages 40-60 and 20%-40% of patients have otologic manifestations. Patients may present with chronic otitis media, hearing loss, tinnitus, and otalgia. Pale granulation tissue in the middle ear and middle ear effusions are the common findings on exam. Conductive hearing loss can be a consequence of hypertrophied submucosa and chronic presence of inflammatory cells. Hearing loss is often mixed; however, vasculitis of the cochlea can lead to sensorineural hearing loss of varying degrees of severity. A flat audiometric pattern has been associated with autoimmune vasculitis processes. Workup for GPA includes the anti-neutrophil cytoplasmic antibody (ANCA). A negative ANCA test does not rule out GPA as there may not be an elevated ANCA titer in a patient without generalized disease. Definitive diagnosis is achieved by biopsy of affected tissue, typically skin, nasal mucosa, or kidney. Immunosuppressive treatment including cyclophosphamide and prednisone can reverse hearing loss and should not be delayed if a biopsy cannot be evaluated. GPA was determined to be unlikely in this case as the patient had ANCA, CRP, ESR, and urinalysis within normal limits and no other systemic manifestations. Imaging is essential to assess for structural, inflammatory, or neoplastic causes. The CT imaging of this patient identified a right-sided opacification of the temporal bone (Figures 3 and 4) in close proximity to the labyrinthine segment of the right facial nerve canal with thinning and possible dehiscence of the inferior aspect of the canal. Soft tissue in the middle ear with erosion of the ossicles or mastoid is suspicious for cholesteatoma with a high negative predictive value. However, without evidence of bony erosion on CT, cholesteatoma can be difficult to differentiate from granulation tissue, mucosal edema, fibrosis, and fluid. Half-Fourier acquisition single-shot turbo spin-echo (HASTE) MRI is a variation of diffusion-weighted imaging (DWI) and has been found to have a sensitivity of 94.1% and specificity of 100% for cholesteatoma. 4 In this patient, T2-weighted and HASTE MRI findings of a diffusion restricting mass in the right middle ear were consistent with cholesteatoma (Figures 5 and 6). Her audiologic finding of right greater than left hearing loss coincides with a right sided cholesteatoma with underlying bilateral hearing loss. The question then is: what led to the development of this cholesteatoma or was it present at birth? The findings are most consistent with a congenital cholesteatoma given intact tympanic membrane with no history of perforation or surgery. In these cases, ectoderm fails to stop migrating at the tympanic ring. Trapped squamous epithelium in the temporal bone can develop into a cholesteatoma; however, presenting symptoms can take many years to manifest. While the diagnosis of congenital cholesteatoma aligns with this patient’s imaging, BORSD may still be of relevance. A case study has reported bilateral congenital cholesteatomas in a patient with BORSD. 5 Additionally, there has been a reported case of right-sided congenital cholesteatoma, right asymptomatic preauricular pits, and bilateral sensorineural hearing loss presenting at 5 years old in both a mother and daughter. 6 For this patient, surgical resection is planned. Hearing aid devices will likely continue to be utilized for residual impairment given the mixed nature of the hearing loss. BONUS ONLINE VIDEOS: VISUAL DIAGNOSIS Read this month’s Clinical Consultation case, then watch the accompanying videos from Hamid R. Djalilian, MD, to review the patient’s imaging for yourself. Video 1. Axial (horizontal) CT of right temporal bone showing an area anteriorly in middle ear not filled with the fluid or soft tissue density. Video 2. Coronal (parallel to the face) CT of right temporal bone showing the middle ear and mastoid are nearly filled with fluid or soft tissue density. Video 3. Sagittal (vertical parallel to the ear) CT of right temporal bone showing the involvement of nearly the entire middle ear and mastoid. Video 4. Axial (horizontal) T2-weighted MRI showing the middle ear and mastoid opacification is hyperintense (brighter than brain) indicating fluid or cholesteatoma filling those areas. Video 5. Axial (horizontal) T1-weighted MRI showing the middle ear and mastoid opacification is isointense (same color as brain). Video 6. Coronal (parallel to the face) HASTE sequence MRI showing the areas seen on CT in the middle ear and mastoid are filled with cholesteatoma. Watch the patient videos online at thehearingjournal.com.