Ross
327 lines
34 KiB
Markdown
327 lines
34 KiB
Markdown
---
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title: "Sensorineural Hearing Loss in Adult"
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docid: "08d468da-fbc3-44f8-8212-6480e0a152c4"
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authors:
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- key: "eef2f839-5706-47b9-89c3-60d8315b2b3a"
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value: "Nicholas A. Koontz, MD"
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breadcrumbs:
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-
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name: "Head and Neck"
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slug: "head-and-neck"
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treeNodeId: "ed24ed8c-5d57-4629-879b-447b82d2973d"
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-
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name: "Differential Diagnosis"
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slug: "differential-diagnosis"
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treeNodeId: "40d68862-8975-4dde-ac2b-ebc43ab0fb5c"
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-
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name: "CPA-IAC and Posterior Fossa"
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slug: "cpa-iac-and-posterior-fossa"
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treeNodeId: "c590eedb-4a3b-4158-a04f-ad880564c992"
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-
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name: "Clinically Based Differentials"
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slug: "clinically-based-differentials"
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treeNodeId: "55dd15ac-e67d-48dd-8134-f52884dab28b"
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-
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name: "Sensorineural Hearing Loss in Adult"
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slug: "sensorineural-hearing-loss-in-adult"
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treeNodeId: null
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category: "Head and Neck"
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documentVersionId: "2268573f-6f13-4d60-b402-841d07de264c"
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imageCount: 32
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lastUpdated: "07/24/18"
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pageDescription: "Sensorineural Hearing Loss in Adult"
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pageKeywords: "Head and Neck, Differential Diagnosis, CPA-IAC and Posterior Fossa, Clinically Based Differentials, Sensorineural Hearing Loss in Adult"
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pageTitle: "Sensorineural Hearing Loss in Adult | STATdx"
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enhancedTitle: "Sensorineural Hearing Loss in Adult"
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type: "DDX"
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references: true
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breadcrumbs:
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- "Head and Neck"
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- "Differential Diagnosis"
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- "CPA-IAC and Posterior Fossa"
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- "Clinically Based Differentials"
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- "Sensorineural Hearing Loss in Adult"
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---
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# ESSENTIAL INFORMATION
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- ## Key Differential Diagnosis Issues
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- Many diagnoses cause sensorineural hearing loss (SNHL)
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- Relative statistical incidence of major differential diagnoses
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- **Vestibular schwannoma**: **90%** of lesions causing SNHL
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- CPA meningioma, epidermoid cyst, aneurysm: 5% of all lesions causing SNHL
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- All other diagnoses in SNHL differential diagnosis list: 5%
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- Best imaging tool
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- MR best for SNHL patients
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- High-resolution/volumetric T2: Best for surgical anatomy, nerve of origin, & fundal CSF cap in setting of vestibular schwannoma
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- T1 C+ T1 fat-saturated: Helps make labyrinthitis, vestibular neuritis, Ramsay Hunt syndrome diagnoses
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- Increasing role of pre- & postcontrast 3D FLAIR in assessing sudden (onset < 72 hours) SNHL
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- Differentiates vascular (methemoglobin → bright inner ear signal on T1 C- & 3D FLAIR C-) from inflammatory (proteinaceous exudate → bright inner ear signal only on 3D FLAIR C-) etiologies
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- Inner ear enhancement on 3D FLAIR C+ identifies blood-labyrinth barrier breakdown
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- ## Helpful Clues for Common Diagnoses
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- **Vestibular Schwannoma**
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- Morphology
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- "Ice cream on cone" mass aligned with CPA-IAC
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- Imaging findings
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- T1 C+ MR: Enhancing lesion ± intramural cysts
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- High-resolution/volumetric T2: Fundal cap size, relationship of tumor to cochlear nerve canal, & (if small) nerve of origin
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- GRE/SWI: ± microhemorrhages with blooming artifact
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- **Meningioma in CPA**
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- Morphology
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- Dural-based mass often asymmetric to porus acusticus
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- Imaging findings
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- T1 C+ MR: Enhancing mass ± dural tails ± CSF-vascular cleft between mass & brainstem
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- **Epidermoid Cyst in CPA**
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- Morphology
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- Insinuating with brainstem margin
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- Imaging findings
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- T1 C+ MR: Nonenhancing mass may be difficult to see
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- DWI: Reduced diffusivity makes diagnosis
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- **Aneurysm in CPA**
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- Morphology
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- Ovoid or fusiform CPA mass; rarely in IAC
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- Imaging findings
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- T1 & T1 C+ MR: Complex signal mass from wall calcification, clot, & flow
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- MRA, CTA, or catheter angiography confirmatory
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- **T-Bone****Fracture**
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- T-bone CT essential; imaging findings
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- Transverse, longitudinal, or complex fracture crosses inner ear structures ± pneumolabyrinth
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- ## Helpful Clues for Less Common Diagnoses
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- **Cochlear Otosclerosis**
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- Pathophysiology: Etiology unknown; osteodystrophy of otic capsule
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- Imaging findings
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- Bone CT: Radiolucent foci in bony labyrinth
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- T1 C+ MR: Multiple enhancing foci in bony labyrinth
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- **Metastases in CPA-IAC**
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- Imaging findings
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- T1 C+ MR: Multiple enhancing lesions involving flocculus, choroid plexus, pia-arachnoid, or dura
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- **Facial Nerve Schwannoma in CPA-IAC**
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- Imaging findings
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- Bone CT: Labyrinthine segment facial nerve canal enlarged = labyrinthine tail
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- T1 C+ MR: Enhancing tubular mass affects CPA-IAC & labyrinthine segment of facial nerve
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- **Lipoma in CPA-IAC**
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- Imaging findings
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- NECT: Fatty lesion of CPA, IAC ± inner ear
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- T1 MR: High-signal lesion as above; fat saturation suppresses fat signal
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- **Large Endolymphatic Sac Anomaly (IP-2)**
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- Most common lesion found in children with bilateral congenital SNHL
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- Imaging findings
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- Bone CT: Large bony vestibular aqueduct ± mild cochlear malformation
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- Axial CT: ≥ 1 mm at midpoint, ≥ 2 mm at operculum
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- MR: Large endolymphatic sac & duct ± incomplete cochlear partitioning &/or deficient modiolus
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- **Intralabyrinthine Schwannoma**
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- Name based on anatomic location: Intracochlear, intralabyrinthine, vestibulocochlear, transmodiolar, transmacular, & transotic types
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- Imaging findings
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- T1 C+ MR: Intralabyrinthine enhancing lesion
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- High-resolution T2 MR: Focal filling defect within high-signal intralabyrinthine fluid
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- **Labyrinthitis**
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- Imaging findings
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- T1 C+ MR: Diffuse (less commonly focal) enhancement of labyrinth
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- Facial or vestibulocochlear nerves may also enhance
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- **Vestibulocochlear****Neuritis**
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- Imaging findings: T1 C+ MR: Linear enhancement in CPA-IAC cisterns
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- **Paget Disease in T-Bone**
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- Clinical: Patient > 50 years of age
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- Imaging findings
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- Bone CT: Expansile bony lesion with cotton-wool appearance; may involve otic capsule
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- T1 C+ MR: Heterogeneous enhancement within expanded T-bone, skull base, & calvarium
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- **Fibrous Dysplasia****in****T-Bone**
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- Clinical: Patient < 30 years of age
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- Imaging findings
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- Bone CT: Expansile lesion with ground-glass/sclerotic & cystic components; spares otic capsule
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- MR: Expansile lesion with heterogeneous signal
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- T1 C+ MR: Heterogeneous avid enhancement mixed with areas of minimal to no enhancement
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- ## Helpful Clues for Rare Diagnoses
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- **Endolymphatic Sac Tumor**
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- Tumor centered in endolymphatic duct or sac area of posterior T-bone
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- Imaging findings
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- Bone CT: Spiculated or coarse calcifications within tumor matrix with thin posterior marginal calcification
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- T1 MR: Multifocal high-signal tumor foci (blood products in tumor matrix)
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- **Sarcoidosis in CPA**
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- Laboratory: CSF lymphocystosis; increased blood angiotensin-converting enzyme (ACE)
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- Morphology: En plaque, nodular, or linear masses
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- Imaging findings
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- T1 C+ MR: Multifocal dural-based enhancing lesions
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- **Superficial Siderosis****in****CPA-IAC**
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- Clinical: Bilateral SNHL with ataxia
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- Imaging findings
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- GRE/SWI MR: Blooming dark signal (hemosiderin) along surface of cerebellum & cranial nerves
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- MR may also be used to identify site of chronic bleeding: Surgical site, aneurysm, tumor, or arteriovenous malformation, including spin
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- **IAC/Temporal Bone Facial Nerve Venous Malformation ("Hemangioma")**
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- Imaging findings
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- CT: Punctate calcification in IAC lesion
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- T1 C+ MR: Enhancing lesion in IAC with focal low-signal areas (calcifications)
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- **Ramsay Hunt Syndrome**
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- Clinical: External ear vesicles ± CNVII or CNVIII neuropathy
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- Imaging findings: T1 C+ MR: Linear enhancing foci in IAC
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- **Susac Syndrome (Retinocochleocerebral Vasculopathy)**
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- Clinical: Classic triad of branch retinal artery occlusions, SNHL (often with vestibular symptoms), & encephalopathy (including headaches)
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- Imaging findings
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- T2/FLAIR MR: Multifocal white matter (WM) lesions, often round & involving mid callosal region
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- T1 C+ MR: Variable enhancement of WM lesions; ± leptomeningeal enhancement
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## References
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# Selected References
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1. [Coffey N et al: Imaging findings in sensorineural hearing loss: a pictorial essay. Can Assoc Radiol J. 68(2):106-115, 2017](http://www.ncbi.nlm.nih.gov/pubmed/?term=27209216%5Bpmid%5D)
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1. [Conte G et al: MR imaging in sudden sensorineural hearing loss. Time to Talk. AJNR Am J Neuroradiol. ePub, 2017](http://www.ncbi.nlm.nih.gov/pubmed/?term=28546251%5Bpmid%5D)
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1. [Lee JI et al: Prognostic Value of Labyrinthine 3D-FLAIR Abnormalities in Idiopathic Sudden Sensorineural Hearing Loss. AJNR Am J Neuroradiol. 37(12):2317-2322, 2016](http://www.ncbi.nlm.nih.gov/pubmed/?term=27516239%5Bpmid%5D)
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1. [Naganawa S et al: Heavily T₂-Weighted 3D-FLAIR Improves the Detection of Cochlear Lymph Fluid Signal Abnormalities in Patients with Sudden Sensorineural Hearing Loss. Magn Reson Med Sci. 15(2):203-11, 2016](http://www.ncbi.nlm.nih.gov/pubmed/?term=26597430%5Bpmid%5D)
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1. [Pakdaman MN et al: Blood-Labyrinth Barrier Permeability in Menière Disease and Idiopathic Sudden Sensorineural Hearing Loss: Findings on Delayed Postcontrast 3D-FLAIR MRI. AJNR Am J Neuroradiol. ePub, 2016](http://www.ncbi.nlm.nih.gov/pubmed/?term=27256854%5Bpmid%5D)
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1. [Cerqueira AC et al: Superficial siderosis of the central nervous system: an unusual cause of sensorineural hearing loss. Arq Neuropsiquiatr. 68(3):469-71, 2010](http://www.ncbi.nlm.nih.gov/pubmed/?term=20602058%5Bpmid%5D)
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1. [Goyault G et al: Leptomeningeal carcinomatosis and sensorineural hearing loss: correlation of labyrinthine enhancement patterns with symptoms. J Neuroradiol. 36(2):98-101, 2009](http://www.ncbi.nlm.nih.gov/pubmed/?term=19144408%5Bpmid%5D)
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1. [Thamburaj K et al: Intratumoral microhemorrhages on T2*-weighted gradient-echo imaging helps differentiate vestibular schwannoma from meningioma. AJNR Am J Neuroradiol. 29(3):552-7, 2008](http://www.ncbi.nlm.nih.gov/pubmed/?term=18079187%5Bpmid%5D)
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1. [Daniels RL et al: Causes of unilateral sensorineural hearing loss screened by high-resolution fast spin echo magnetic resonance imaging: review of 1,070 consecutive cases. Am J Otol. 21(2):173-80, 2000](http://www.ncbi.nlm.nih.gov/pubmed/?term=10733180%5Bpmid%5D)
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1. [Davidson HC et al: MR evaluation of vestibulocochlear anomalies associated with large endolymphatic duct and sac. AJNR Am J Neuroradiol. 20(8):1435-41, 1999](http://www.ncbi.nlm.nih.gov/pubmed/?term=10512225%5Bpmid%5D)
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1. [Swartz JD: Sensorineural hearing deficit: a systematic approach based on imaging findings. Radiographics. 16(3):561-74, 1996](http://www.ncbi.nlm.nih.gov/pubmed/?term=8897624%5Bpmid%5D)
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## Images
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### Selected Images
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**Vestibular Schwannoma**
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*Axial T1 C+ FS MR shows the typical appearance of a CPA-IAC vestibular schwannoma <img src='img/arrows/WS.png'/> with avid, heterogeneous enhancement. Note tumor growth along the location of the vestibular nerve within the posterior IAC <img src='img/arrows/WO.png'/>.*
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**Vestibular Schwannoma**
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*Axial T1 C+ FS MR shows the typical appearance of a CPA-IAC vestibular schwannoma <img src='img/arrows/WS.png'/> with avid, heterogeneous enhancement. Note tumor growth along the location of the vestibular nerve within the posterior IAC <img src='img/arrows/WO.png'/>.*
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**Vestibular Schwannoma**
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*Axial SWI MR in a CPA-IAC vestibular schwannoma <img src='img/arrows/WS.png'/> shows punctate foci of gradient susceptibility <img src='img/arrows/WC.png'/> from microhemorrhage, a feature that can help distinguish CPA-IAC schwannoma from meningioma.*
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**Meningioma in CPA**
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*Axial T1 C+ FS MR shows the typical appearance of a CPA meningioma <img src='img/arrows/WS.png'/>, which is avidly enhancing and extends into the IAC <img src='img/arrows/WO.png'/>. Note the characteristic dural tails <img src='img/arrows/WC.png'/>, which help differentiate meningioma from schwannoma.*
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**Epidermoid Cyst in CPA**
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*Axial DTI trace image through the posterior fossa shows a typical epidermoid cyst <img src='img/arrows/WS.png'/> with reduced diffusivity. Note the scalloped, insinuating margins <img src='img/arrows/WO.png'/>, which frequently encase cranial nerves and vessels and can make surgical resection fraught with peril.*
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**Aneurysm in CPA**
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*Axial T2WI MR shows a CPA vertebral artery aneurysm as an ovoid mass <img src='img/arrows/WS.png'/> with complex wall signal, which bows the vestibulocochlear nerve <img src='img/arrows/BO.png'/> posterolaterally.*
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**T-Bone Fracture**
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*Axial bone CT shows a complex, transversely oriented T-bone fracture <img src='img/arrows/WS.png'/> that involves the otic capsule and disrupts the cochlea <img src='img/arrows/WO.png'/>. The mastoid air cells and middle ear are opacified with blood, corresponding with hemotympanum on otoscopy.*
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**Cochlear Otosclerosis**
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*Axial bone CT shows cochlear otosclerosis yielding SNHL. Note confluent otic capsule lucency <img src='img/arrows/WS.png'/> adjacent to the cochlea. Patients commonly have fenestral involvement with lucency near the fissula ante fenestram <img src='img/arrows/WO.png'/>, contributing a conductive component to hearing loss. Note the prior partial ossicular replacement prosthesis <img src='img/arrows/WC.png'/>.*
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**Metastases in CPA-IAC**
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*Axial FLAIR C+ MR shows leptomeningeal metastases from melanoma with enhancement at the fundus of bilateral IACs <img src='img/arrows/WS.png'/> extending into the basal turn of the cochlea <img src='img/arrows/WO.png'/> bilaterally.*
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**Facial Nerve Schwannoma in CPA-IAC**
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*Axial T1 C+ SPGR MR shows a facial nerve schwannoma <img src='img/arrows/WS.png'/> involving the left CPA-IAC. In this case, the labyrinthine tail of enhancement <img src='img/arrows/WO.png'/> extends to the asymmetrically enhancing geniculate ganglion region <img src='img/arrows/WC.png'/>, following the expected course of the facial nerve.*
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**Lipoma in CPA-IAC**
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*Coronal T1 MR of a left CPA-IAC lipoma shows a T1-bright lobular mass <img src='img/arrows/WS.png'/> extending into the IAC <img src='img/arrows/WO.png'/>. The presence of chemical shift artifact <img src='img/arrows/WC.png'/> at the tumor-CSF (i.e., water) margin confirms the presence of fat within this mass.*
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**Large Endolymphatic Sac Anomaly (IP-2)**
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*Axial T2WI FS MR shows a large endolymphatic sac <img src='img/arrows/WS.png'/> along the posterior wall of the T-bone associated with a malformed cochlea (modiolar deficiency, incomplete apical septation, and bulbous apical turn) <img src='img/arrows/WO.png'/>.*
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**Intralabyrinthine Schwannoma**
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*Coronal T1 C+ FS MR of an intracochlear schwannoma shows abnormal enhancement in the middle turn of the right cochlea <img src='img/arrows/WS.png'/>. Note the normal postcontrast appearance of the contralateral cochlea for comparison <img src='img/arrows/WO.png'/>.*
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**Labyrinthitis**
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*Axial T1 C+ FS MR in a patient with acute otomastoiditis complicated by labyrinthitis shows enhancement in the cochlea <img src='img/arrows/WS.png'/>. There is additional vestibulocochlear neuritis with linear enhancement at the IAC fundus <img src='img/arrows/WO.png'/>. Note enhancing mastoid/middle ear disease <img src='img/arrows/WC.png'/> and dural enhancement <img src='img/arrows/BS.png'/> due to marked inflammation.*
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**Vestibulocochlear Neuritis**
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*Axial T1 C+ FS MR shows vestibulocochlear neuritis in a patient with rapid onset of sensorineural hearing loss. Note the area of linear enhancement in the proximal IAC <img src='img/arrows/WS.png'/>.*
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### Additional Images
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**Fibrous Dysplasia in T-Bone**
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*Axial bone CT shows expansile ground-glass density focus of fibrous dysplasia <img src='img/arrows/WS.png'/> affecting the squamous, tympanic, & mastoid portions of the T-bone. Note relative sparing of the otic capsule <img src='img/arrows/WO.png'/>.*
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**Endolymphatic Sac Tumor**
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*Axial T1WI MR reveals a tumor along the posterior wall of the T-bone with high-signal foci <img src='img/arrows/WO.png'/> that is highly suggestive of an endolymphatic sac tumor.*
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**Sarcoidosis in CPA**
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*Axial T1 C+ FS MR demonstrates thick enhancing dural-based sarcoidosis in the left CPA <img src='img/arrows/WS.png'/> and IAC <img src='img/arrows/WO.png'/> mimicking en plaque meningioma.*
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**Superficial Siderosis in CPA-IAC**
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*Axial T2* GRE MR shows superficial siderosis on the surface of the posterior fossa structures (linear low signal), including cerebellar folia <img src='img/arrows/WC.png'/>, flocculi <img src='img/arrows/WO.png'/>, and vestibulocochlear nerves <img src='img/arrows/WS.png'/>.*
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**IAC/Temporal Bone Facial Nerve Venous Malformation ("Hemangioma")**
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*Axial bone CT reveals punctate calcifications <img src='img/arrows/WS.png'/> in the IAC suggesting the diagnosis of IAC hemangioma. Enhanced MR showed an enhancing mass in this location.*
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**Ramsay Hunt Syndrome**
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*Axial T1 C+ MR shows area of crescentic enhancement in the IAC fundus <img src='img/arrows/WS.png'/> associated with tympanic segment of the facial nerve asymmetric enhancement <img src='img/arrows/WO.png'/>. EAC vesicles were present, characteristic of Ramsey Hunt syndrome.*
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**Susac Syndrome (Retinocochleocerebral Vasculopathy)**
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*Coronal T2 FS MR in a patient with retinocochleocerebral vasculopathy (Susac syndrome) shows a characteristic round, hyperintense lesion in the splenium of the corpus callosum <img src='img/arrows/WS.png'/>.*
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**Vestibular Schwannoma**
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*Axial T1 C+ FS MR shows typical mid sized CPA-IAC vestibular schwannoma. "Ice cream" (CPA component) <img src='img/arrows/WS.png'/> "on cone" (IAC component) <img src='img/arrows/WO.png'/> morphology is highly suggestive of this diagnosis.*
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**Meningioma in CPA**
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*Axial T1 C+ FS MR shows the sessile morphology of meningioma as it "sits" on the posterior T-bone wall. Note the characteristic dural tail <img src='img/arrows/WO.png'/> and dural artery <img src='img/arrows/WS.png'/> feeding the tumor center.*
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**Epidermoid Cyst in CPA**
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*Axial DWI MR shows a CPA epidermoid identified by its reduced diffusivity <img src='img/arrows/WC.png'/>. CPA epidermoids often are not directly over the porus acusticus, as in this case.*
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**T-Bone Fracture**
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*Axial bone CT shows an oblique T-bone fracture <img src='img/arrows/WS.png'/> traversing the oval window and extending to the IAC area <img src='img/arrows/WO.png'/>. Notice the air bubble (pneumolabyrinth) along the anterior margin of the vestibule <img src='img/arrows/WC.png'/>.*
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**Cochlear Otosclerosis**
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*Axial bone CT shows severe otosclerosis as radiolucent foci along the medial middle ear wall <img src='img/arrows/WS.png'/> (fenestral otosclerosis) and within the bony labyrinth <img src='img/arrows/WO.png'/> (cochlear otosclerosis).*
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**Metastases in CPA-IAC**
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*Axial T2WI MR demonstrates a right floccular metastasis <img src='img/arrows/WS.png'/> with associated high-signal cerebellar and brachium pontis edema. A normal left flocculus <img src='img/arrows/WO.png'/> is also seen.*
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**Facial Nerve Schwannoma in CPA-IAC**
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*Axial T1 C+ FS MR reveals an enhancing facial nerve schwannoma traversing the CPA <img src='img/arrows/WC.png'/> and IAC <img src='img/arrows/WS.png'/> into the facial nerve labyrinthine segment <img src='img/arrows/WO.png'/>. This labyrinthine tail is characteristic.*
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**Lipoma in CPA-IAC**
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*Axial T1 MR demonstrates a CPA <img src='img/arrows/WS.png'/> and intravestibular <img src='img/arrows/WO.png'/> lipoma. Notice that the CPA lipoma effaces the most proximal vestibulocochlear nerve bundle <img src='img/arrows/WC.png'/>. These lesions are left alone.*
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**Intralabyrinthine Schwannoma**
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*Axial T1 C+ FS MR demonstrates a nodule of enhancing tissue in the vestibule <img src='img/arrows/WS.png'/> of the inner ear secondary to intralabyrinthine schwannoma. CT of the T-bone was normal.*
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**Paget Disease in T-Bone**
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*Axial bone CT shows late-phase Paget disease with diffuse bony expansion with areas of demineralization <img src='img/arrows/WS.png'/>. Notice that the bony labyrinth along the anterior cochlear surface is involved <img src='img/arrows/WO.png'/>.*
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**Labyrinthitis**
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*Axial T1 C+ FS MR shows enhancement of the middle ear <img src='img/arrows/WC.png'/>, inner ear membranous labyrinth <img src='img/arrows/WS.png'/>, and IAC <img src='img/arrows/WO.png'/> in this pediatric patient with acute actinomycosis.*
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