Imaging of inflammatory and infectious diseases in the temporal bone

Imaging Update of Congenital Hearing Loss: A Recent Insight Imaging Including 3D MRI Cisternography Prior to Cochlear Implant

SNHL in children is an important issue. Cochlear implant is a highly technological device that is surgically inserted in the cochlea to solve this issue. To evaluate types of anomalies of the inner ear in children with sensorineural hearing loss in a tertiary care hospital and confirm that the routine MRI, MR cisternography and HRCT provides the surgeon with the imaging finding and criteria of patients candidates for CI. Patients and method: 600 patients with SNHL underwent HRCT and MRI. CT examinations were normal in 457 patients (76.2%) and 143 patients (23.8%) with inner ear anomalies. MRI examinations were normal in 440 patients (73.3%) and had inner ear anomalies in 160 patients (26.7%). 3D bFFE and 3D DRIVE was summarized. The 3D bFFE sequence was statistically significantly better than the 3D DRIVE for the demonstration of the cochlear vestibule. Superior, inferior vestibular nerves and facial nerves while 3D DRIVE is superior to 3D bFFE in the visualization of the semicircular canals. HRCT and MRI provide accurate anatomical delineation of complex inner ear structures and 3D improves pre-implant evaluation.

Cochlear Implantation: Systematic Approach to Preoperative Radiologic Evaluation

Sensorineural hearing loss results from abnormalities that affect the hair cells of the membranous labyrinth, inner ear malformations, and conditions affecting the auditory pathway from the cochlear nerve to the processing centers of the brain. Cochlear implantation is increasingly being performed for hearing rehabilitation owing to expanding indications and a growing number of children and adults with sensorineural hearing loss. An adequate understanding of the temporal bone anatomy and diseases that affect the inner ear is paramount for alerting the operating surgeon about variants and imaging findings that can influence the surgical technique, affect the choice of cochlear implant and electrode type, and help avoid inadvertent complications. In this article, imaging protocols for sensorineural hearing loss and the normal inner ear anatomy are reviewed, with a brief description of cochlear implant devices and surgical techniques. In addition, congenital inner ear malformations and acquired causes of sensorineural hearing loss are discussed, with a focus on imaging findings that may affect surgical planning and outcomes. The anatomic factors and variations that are associated with surgical challenges and may predispose patients to periprocedural complications also are highlighted. ^© RSNA, 2023 Quiz questions for this article are available through the Online Learning Center. Online supplemental material and the slide presentation from the RSNA Annual Meeting are available for this article.

The Relationship Between Temporal Bone Pneumatization Pattern and Sinus Mucosal Thickness Grading on Computed Tomography Scans of Paranasal Sinuses

The relationship between temporal bone pneumatization (TBP) pattern and sinus mucous thickness grading on computed tomography scans of paranasal sinuses was investigated. In this cross-sectional study, a total of 200 temporal bones and paranasal sinuses were evaluated in CT scans of 100 patients with chronic sinusitis (CRS). The mucosal thickness of paranasal sinuses was classified into two groups (0-6 and 7-12) according to the Lund-Mackay (LM) staging system. Also, pneumatization patterns of petrous apex and perilabyrinthine regions were classified according to Jadvah et al. method. Data were analyzed using Chi-square and Fisher's exact tests. The most common pneumatization pattern in the petrous apex was pattern A (49.5%) and in the perilabyrinthine region was pattern B (50%). In the petrous apex, the highest frequencies of pattern A (51.7%) and pattern C (24.6%), among other pneumatization patterns, were found in score range of 7-12 and 0-6, respectively, which was statistically significant (P = 0.017). Although in the perilabyrinthine region, the highest frequencies of pattern A (24.1%) and pattern C (32.7%) were in LM score ranges of 7-12 and 0-6, respectively, no significant difference was found (P = 0.589). The petrous apex pneumatization decreases with an increase in the severity of CRS, which can be in response to the eustachian tube dysfunction and common pathogens with CRS. A similar relationship was also found in the perilabyrinthine region, although it was not statistically significant. No significant relationship between TBP and severity of CRS was found in the age and sex groups.

Petrositis caused by fluconazole-resistant candida: case report and literature review

Background

Petrositis is a rare and fatal complication associated with otitis media. It is most likely caused by bacterial infections, but in some cases it is caused by fungal infections.

Case study

The case in this report is associated with fungal petrositis. The clinical symptoms are: ear pain from chronic otitis media, severe headache, peripheral facial palsy and diplopia. The case was finally confirmed through imaging of middle ear, bacterial culture, pathology, and blood Metagenomic next-generation sequencing (mNGS) test. The patient was treated with sensitive antifungal drugs.

Conclusion

Drug treatment is conservative but efficient method in this case. mNGS can provide pathogenic reference, when antibiotic is not efficient enough for fungal infections or drug-resistant fungal infections cases. This allows we to adjust drug use for the treatment.

Floating labyrinth: A unique finding on CT scan

We report a case of a 67-year-old female patient that presented to the emergency department with complete right facial paralysis, progressive hearing loss and chronic otorrhea. A unique finding on CT scan is reported: a “floating labyrinth” – cochlea, vestibule and semicircular canals extensively surrounded by soft tissue density material but with intact thinned otic capsule walls. A transotic approach was performed for removal of noncholesteatomatous inflammatory tissue; intravenous antibiotics and corticosteroids led to partial recovery of facial nerve function. A chronic suppurative otitis media with necrotic osteomyelitis and bony sequestrum in a severe context of AIDS is the likely cause. An immunosuppressive disease should be suspected in atypical presentations of chronic suppurative otitis media without cholesteatoma.

MRI of the Internal Auditory Canal, Labyrinth, and Middle Ear: How We Do It

MRI is firmly established as an essential modality in the imaging of the temporal bone and lateral skull base. It is used to evaluate normal anatomic structures, evaluate for vestibular schwannomas, assess for inflammatory and/or infectious processes, and detect residual and/or recurrent cholesteatoma. It is also extensively used in pre- and postoperative evaluations, particularly in patients with vestibular schwannomas and candidates for cochlear implantation. Nevertheless, despite the widespread use of MRI for these purposes, many radiologists remain unfamiliar with the complex anatomy and expected imaging findings with such examinations. The purpose of this review is to provide an overview of the most useful MRI sequences for internal auditory canal and labyrinthine imaging, review the relevant anatomy, and discuss the expected appearances of the most commonly encountered pathologic entities. In addition, the features at pre- and postprocedural MRI will be discussed to help ensure that diagnostic radiologists may be of greatest use to the ordering physicians. © RSNA, 2020.

[Overview of modern methods for the diagnosis of exudative otitis media]

Modern methods for diagnosis of exudative otitis media (EOM) have great potential, however, the problem of diagnosis of EOM is still relevant. The article describes the methods of modern diagnostics that are widely used in the daily practice of an otolaryngologist. The basic principles, advantages and disadvantages of generally accepted diagnostic methods for EOM are presented. The method of optical coherence tomography (OCT) is described as a method of studying biological tissues, which is used in many fields of medicine. Information is provided on the possibilities of OCT in the diagnosis of diseases of the ENT organs and, in particular, of the middle ear. The results of studies of the tympanic cavity structures in various inflammatory conditions, the possibilities of intrasurgery use of OCT, as well as the possibilities and perspectives of introducing OCT into the practice of an otorhinolaryngologist in the diagnosis of exudative otitis media are described.

Conductive hearing loss with a "dry middle ear cleft"-A comprehensive pictorial review with CT

Conductive hearing loss (CHL) commonly results from middle ear fluid and inflammation (otitis media). Less commonly in patients with CHL, the middle ear cleft is well aerated or 'dry' with absence of soft tissue or fluid clinically and on imaging. There are numerous causes for this but they can be clinically challenging to diagnose. This pictorial review aims to illustrate and discuss the CT features of both common and less common causes of CHL in patients with a "dry middle ear cavity".

Bilateral Labyrinthine and Internal Auditory Canal Enhancement in an Infant With Severe Labyrinthine Dysplasia: A Previously Unreported Phenomenon

OBJECTIVE

To describe a novel case of congenital profound bilateral sensorineural hearing loss in a patient with bilateral nodular internal auditory canal and labyrinthine enhancement and temporal bone dysplasia.

PATIENTS

A 76-day-old female was referred to the authors' center for evaluation of congenital deafness. Behavioral observations and objective audiometric evaluation demonstrated bilateral profound sensorineural hearing loss and a comprehensive multidisciplinary evaluation identified compound heterozygous pathogenic variants in MYO7A, a gene associated with Usher Syndrome Type 1B or DFNB2. Computed tomography and contrast-enhanced magnetic resonance imaging studies demonstrated bilateral temporal bone anomalies with unique middle and inner ear malformations, as well as unique contrast enhancement in the membranous labyrinth, internal auditory canals, and cranial nerves, which have not been previously described with MYO7A variants.

INTERVENTIONS

Given the potential risk for progressive bilateral labyrinthitis ossificans, bilateral simultaneous cochlear implantation was performed at 4 months of age.

MAIN OUTCOME MEASURES

Subsequent audiologic follow up after implantation shows significantly improved access to auditory information and increased vocalizations. At last testing, speech and language skills for both receptive and expressive language abilities were found to be commensurate with her chronological age.

CONCLUSION

We report a novel presentation and imaging findings of congenital bilateral profound sensorineural hearing loss in a patient with nodular internal auditory canal and labyrinthine enhancement and coexisting inner ear dysplasia. Despite the multiple radiologic abnormalities, the patient has demonstrated good benefit from cochlear implantation. Future study of rare variants of congenital deafness, such as this, is critical toward defining new disease processes and determining optimal treatment.

Indications and radiological findings of acute otitis media and its complications

Most cases of acute otitis media resolve with antibiotics and imaging is not required. When treatment fails or a complication is suspected, imaging plays a crucial role. Since the introduction of antibiotic treatment, the complication rate has decreased dramatically. Nevertheless, given the critical clinical relevance of complications, the importance of early diagnosis is vital. Our objective was to review the clinical and radiological features of acute otitis media and its complications. They were classified based on their location, as intratemporal or intracranial. Imaging makes it possible to diagnose the complications of acute otitis media and to institute appropriate treatment. Computed tomography is the initial technique of choice and, in most cases, the ultimate. Magnetic resonance is useful for evaluating the inner ear and when accurate evaluation of disease extent or better characterization of intracranial complications is required.

Computed Tomography Staging of Middle Ear Cholesteatoma

Background

To establish computed tomography (CT) staging of middle ear cholesteatoma and assess its impact on the selection of the surgical procedure.

Material/Methods

Prospective study was conducted on 61 consecutive patients (mean age 26.8 years) with middle ear cholesteatoma. CT scan of the temporal bone and surgery were performed in all patients. CT staging classified cholesteatoma according to its location in the tympanic cavity (T); extension into the mastoid (M); and associated complications (C). Cholesteatoma was staged as stage I (T1, T2), stage II (T3, M1, M2, C1), and stage III (C2).

Results

The overall sensitivity of CT staging of cholesteatoma compared to surgery was 88% with excellent agreement and correlation between CT findings and intra-operative findings (K=0.863, r=0.86, P=0.001). There was excellent agreement and correlation of CT staging with surgical findings for T location (K=0.811, r=0.89, P=0.001), good for M extension (K=0.734, r=0.88, P=0.001), and excellent for associated C complications (K=1.00, r=1.0, P=0.001). Atticotympanotomy was carried out in stage I (n=14), intact canal wall surgery was performed in stage II (n=38), and canal wall down surgery was done in stage III (n=5) and stage II (n=4).

Conclusions

We established CT staging of middle ear cholesteatoma that helps surgeons to select an appropriate surgery.

Diagnostic imaging modalities in head and neck disease

BACKGROUND

Because of the complex anatomy of the head and neck region, conventional projection radiography alone is unreliable and carries a high risk of misdiagnosis. The poor risk-benefit ratio of conventional radiography has led to their replacement by tomographic imaging for nearly all studies in this region.

METHOD

This review is based on pertinent articles retrieved by a selective search in the PubMed database (January 1980 to May 2013) as well as on the relevant guidelines from Germany and abroad.

RESULTS

The indication for diagnostic imaging in the anatomically complex head and neck region should be established for a specific type of imaging study on the basis of a thorough clinical examination. Conventional films, though easy to obtain, often cannot answer the diagnostic question and may yield confusing information leading to misdiagnosis. Computed tomography (CT) has the best risk-benefit profile and a high diagnostic value, but low-dose protocols have not yet been put into use in all centers. Magnetic resonance imaging (MRI) is best for bone and soft-tissue diagnosis, but consumes more resources. Digital volume tomography (DVT) is another type of three-dimensional, sectional imaging with high local resolution; the associated radiation exposure and image quality are generally both low, but may vary depending on the apparatus used. DVT cannot be used to evaluate the soft tissues. Ultrasonography can be used to evaluate superficial structures in the head and neck region; nuclear imaging can be used to evaluate thyroid disease and cancer.

CONCLUSION

Inflammatory, traumatic, and neoplastic diseases of the head and neck are best evaluated with cross-sectional imaging (CT, MRI) in accordance with current guidelines. Conventional x-rays should, in general, only be used for dental evaluation, with rare exceptions.

Temporal bone imaging

Temporal bone imaging is performed for a variety of clinical conditions addressed in the outpatient and acute care setting ranging from hearing loss to trauma. Recent advances in magnetic resonance technology have enhanced the assessment of fine anatomic temporal bone detail and improved the diagnostic sensitivity for important pathology. For example, non-echo planar diffusion weighted imaging increases detection rate and diagnostic confidence of recurrent cholesteatoma. This chapter will focus on relevant temporal bone clinical entities and new MR developments that have come into clinical practice.

A mistaken identity: rhabdomyosarcoma of the middle ear cleft misdiagnosed as chronic suppurative otitis media with temporal lobe abscess

A 5-year-old girl presented with a 3-month history of left side facial palsy, followed sequentially by purulent ear discharge, complete external ophthalmoplaegia and blurred vision. On clinical examination she was febrile with left-sided conductive hearing loss. She was clinically diagnosed to have chronic suppurative otitis media of the unsafe type with petrous apicitis, middle cranial fossa abscess and cavernous sinus involvement. Preliminary CT scan findings were reported as a large left temporal lobe abscess and left otitis media with cholesteatoma. MRI of the brain obtained later corroborated the abnormalities detected on the CT scan. Ten days after admission, a mass was seen protruding from the external auditory canal. A biopsy of the mass was obtained and sent for histopathological examination. Meanwhile, review of the MRI suggested an aggressive neoplasm such as sarcoma/rhabdomyosarcoma. Histopathology clinched the final diagnosis of an anaplastic type of embryonal rhabdomyosarcoma of the middle ear cleft.

High-resolution 3-D T2-weighted imaging in the diagnosis of labyrinthitis ossificans: emphasis on subtle cochlear involvement

BACKGROUND

Meningitis is the most common cause of acquired sensorineural hearing loss (SNHL) in children. Labyrinthitis ossificans develops in a significant number of patients with meningitis-related SNHL. Reduced T2 signal on MRI within the membranous labyrinth is often noted in the fibrous and ossifying stages of labyrinthitis ossificans.

OBJECTIVE

The purpose of this study is to demonstrate the distribution and extent of involvement of the cochlea in children being evaluated for labyrinthitis ossificans; using high-resolution 3-D T2-weighted imaging, and to evaluate for subtle involvement of the scala tympani within the basal turn of the cochlea.

MATERIALS AND METHODS

A retrospective review from 2002 to 2012 was performed using a cochlear implant database and PACS search function. Twenty-four patients were found to have MR findings consistent with labyrinthitis ossificans, 13 previously reported. Axial 3-D T2-weighted sequences were obtained in all patients. The presence of abnormal decreased T2 signal within the scala tympani and vestibuli of the cochlea was noted and graded according to the extent. The electronic medical record was reviewed for audiometry and risk factors as well as correlative operative findings.

RESULTS

The average age at imaging was 4.2 years. M:F ratio = 5:1. Eighty-eight percent (21/24) of patients had bilateral SNHL. The most common risk factor for labyrinthitis ossificans was meningitis (19/24 or 79%). Eighteen (75%) patients had a history of bacterial meningitis. The mean age for the onset of labyrinthitis was 1.2 years with an average of 2.2-year interval to imaging. Nineteen patients (79%) underwent placement of a cochlear implant. Cochlear obstruction was documented in 83% (40/48) of the ears. Lower grade (1) cochlear obstruction was present in 14 ears and limited to the scala tympani. Statistical analysis was performed correlating MRI imaging and surgical findings.

CONCLUSION

Subtle, isolated involvement of the scala tympani within the proximal basal turn is a common finding in labyrinthitis ossificans and history typical for meningitis is not uniformly present. The extent of cochlear obstruction is important and has surgical implications.

Reliability of preoperative multidetector computed tomography scan in patients with chronic otitis media

OBJECTIVE

The objectives of this study were to specify the objective criteria of existence of cholesteatoma in chronic otitis media on the preoperative multidetector computed tomography (MDCT) and to evaluate the complications of disease.

METHODS

We compared the results of preoperative MDCT scan with intraoperative findings in 71 patients (22 women, 49 men; mean age, 16-73 years) who had mastoidectomy operation between January 2008 and May 2012. Multidetector computed tomography evaluations of temporal bone were performed on a workstation using high-spatial-resolution magnified images with intended angle and plane.

RESULTS

We observed cholesteatoma formation in all patients with scutum erosion (n = 11), dural exposure (n = 6), and lateral semicircular canal fistula (n = 5). Computed tomography revealed these findings with 100% sensitivity. Distortion of ossicular integrity (n = 11) and facial canal dehiscence (n = 5) was significantly higher in cholesteatoma patients. Using the criteria of osteolysis, the sensitivity, specificity, and the accuracy rates of MDCT in detecting cholesteatoma were 71%, 93%, and 88%, respectively. The best diagnostic clue of a cholesteatoma was a mass-like soft tissue located in a retraction pocket in the posterosuperior quadrant of the Shrapnell membrane, causing widening of Prussak space and scutum erosion. Evaluation of computed tomography scan showed nearly 100% sensitivity in detecting tympanic opacification, dural height, dehiscence of lateral semicircular canal, tegmen tympani erosion, and deformation of malleoincudal articulation. However, its contribution to detecting minor ossicular erosion, facial canal dehiscence, and incudostapedial joint evaluation was limited.

CONCLUSIONS

Preoperative assessment of chronic otitis media via MDCT with intended angle and plane produces important guidance to understand the extent of disease and to prevent possible intraoperative complications.

Colesteatoma: utilidade da sequência de difusão sem echo-planar

Colesteatomas são lesões císticas congênitas ou adquiridas que acometem as orelhas e que podem apresentar padrões típicos aos estudos de tomografia computadorizada, em função de suas características expansivas e tendência a promover erosão óssea. Entretanto, particularmente nos casos de resíduo ou recorrência pós-cirúrgica, a distinção entre colesteatoma e tecido inflamatório pode ser bastante difícil e, não raro, impossível com base somente nos achados tomográficos. A avaliação por ressonância magnética pode ser útil, particularmente neste contexto, uma vez que as sequências pós-contraste obtidas tardiamente e a difusão podem demonstrar padrões distintos nestas duas situações. Os artefatos condicionados pela interface ar/osso na região das mastoides podem limitar bastante a utilização da sequência de difusão echo-planar. A sequência de difusão sem echo-planar é uma alternativa na solução deste problema por estar menos sujeita a este tipo de artefato, fornecendo ainda imagens com maior resolução espacial e com espessuras de corte mais finas, as quais permitem a detecção de colesteatomas de pequenas dimensões.

Pediatric sensorineural hearing loss, part 2: syndromic and acquired causes

This article is the second in a 2-part series reviewing neuroimaging in childhood SNHL. Previously, we discussed the clinical work-up of children with hearing impairment, the classification of inner ear malformations, and congenital nonsyndromic causes of hearing loss. Here, we review and illustrate the most common syndromic hereditary and acquired causes of childhood SNHL, with an emphasis on entities that demonstrate inner ear abnormalities on cross-sectional imaging. Syndromes discussed include BOR syndrome, CHARGE syndrome, Pendred syndrome, Waardenburg syndrome, and X-linked hearing loss with stapes gusher. We conclude the article with a review of acquired causes of childhood SNHL, including infections, trauma, and neoplasms.

Diffusion-weighted magnetic resonance imaging of the temporal bone

This paper summarizes the value of diffusion-weighted magnetic resonance imaging in the evaluation of temporal bone pathology. It highlights the use of different types of diffusion-weighted magnetic resonance imaging in the different types of cholesteatoma, prior to first stage surgery and prior to second look surgery. The value of diffusion-weighted magnetic resonance imaging in the evaluation of pathology of the apex of the petrous bone and the cerebellopontine angle is also discussed.

Different imaging techniques in the head and neck: Assets and drawbacks

In this review, the gold standard imaging techniques for the head and neck and the latest upcoming techniques are presented, by comparing computed tomography (CT), magnetic resonance imaging and positron emission tomography-CT, as well as ultrasound, depending on the examined area. The advantages and disadvantages of each examination protocol are presented. This article illustrates the connection between the imaging technique and the examined area. Therefore, the head and neck area is divided into different sections such as bony structures, nervous system, mucous membranes and squamous epithelium, glandular tissue, and lymphatic tissue and vessels. Finally, the latest techniques in the field of head and neck imaging such as multidetector CT, dual-energy CT, flash CT, magnetic resonance angiography, spectroscopy, and diffusion tensor tractography using 3 tesla magnetic resonance are discussed.