Characteristic MR findings suggesting presumed labyrinthine hemorrhage

Four-hour-delayed 3D-FLAIR MRIs in patients with acute unilateral peripheral vestibulopathy

OBJECTIVE

Conventionally, MRI aids in differentiating acute unilateral peripheral vestibulopathy/vestibular neuritis (AUPV/VN) from mimickers. Meanwhile, the diagnostic utility of MRIs dedicated to the inner ear remains to be elucidated for diagnosing AUPV/VN.

METHODS

We prospectively recruited 53 patients with AUPV/VN (mean age ± SD = 60 ± 15 years, 29 men). Initial MRIs were performed with a standard protocol, and an additional axial 3D-fluid-attenuated inversion recovery (3D-FLAIR) sequence was obtained 4 h after intravenous injection of gadoterate meglumine. Abnormal enhancement was defined as a signal intensity that exceeded the mean + 2SD value on the healthy side. The findings of neurotologic evaluation and MRIs were compared.

RESULTS

Overall, the inter-rater agreement for gadolinium enhancement was 0.886 (Cohen's kappa coefficient). Enhancement was observed in 26 patients (49%), most frequently in the vestibule (n = 20), followed by the anterior (n = 12), horizontal (HC, n = 8), posterior canal (n = 5), and superior (n = 3) and inferior (n = 1) vestibular nerves. In multivariable logistic regression analysis, the enhancement was associated with decreased HC gain in video head-impulse tests (p = 0.036), increased interaural difference in ocular vestibular-evoked myogenic potentials (p = 0.001), and a longer onset-to-MRI time span (p = 0.024). The sensitivity and specificity were 92.3% and 81.5%, respectively, with an area under the curve of 0.90 for predicting gadolinium enhancement.

INTERPRETATION

Robust gadolinium enhancement was observed on 4-hour-delayed 3D-FLAIR images in nearly half of the patients with AUPV/VN, with a good correlation with the results of neurotologic evaluation. The positivity may be determined by the extent of vestibular deficit, timing of imaging acquisition, and possibly by the underlying etiology causing AUPV/VN. MRIs may aid in delineating the involved structures in AUPV/VN.

White Matter Hyperintensity in Patients with Sudden Sensorineural Hearing Loss

OBJECTIVE

To compare white matter hyperintensities (WMHs) on T2-weighted magnetic resonance imaging (MRI) of patients with sudden sensorineural hearing loss (SSNHL) and analyze subpopulations with age-matched controls.

METHODS

T2-weighted MRI scans of 150 patients with SSNHL were assessed for WMHs and compared with the data of 148 healthy age-matched adults. Assessments of WMHs included independent grading of deep white matter hyperintensities (DWMHs) and periventricular hyperintensities (PVHs). WMH severity was visually rated using the Fazekas and Mirsen scales by two independent observers.

RESULTS

Fazekas grades for PVHs (p < 0.001) and DWMHs (p < 0.001) of SSNHL patients were found to be significantly greater than those of healthy participants. The average Mirsen grades for DWMHs of healthy and SSNHL patients were evaluated to be 0.373 ± 0.550 and 2.140 ± 0.859, respectively. Mirsen grades for DWMHs of SSNHL patients were found to be significantly greater (p < 0.001) than those of healthy participants. The Mirsen scale was found to have higher sensitivity (p < 0.001) than the Fazekas scale in grading PVHs and DWMHs. No significant difference (p = 0.24) was found in specificities between the two scales.

CONCLUSIONS

Patients with sudden hearing loss have a much higher likelihood of having periventricular and deep white matter hyperintensities compared to age-matched controls. These findings indicate that sudden hearing loss patients are more likely to have microvascular changes in the brain, which may indicate a vascular and/or migraine origin to sudden sensorineural hearing loss.

Sudden unilateral audiovestibular loss due to acute labyrinthine haemorrhage can be missed on early MRI brain sequences: case report

Background

Labyrinthine haemorrhage is a rare vascular disorder often presenting with the triad of acute vertigo, sudden sensorineural hearing loss and tinnitus. There are minimal reports on imaging progression over the acute period.

Index case

A woman in her mid-40s presented with acute vertigo, sudden left-sided hearing loss and tinnitus, consistent with acute unilateral audiovestibular loss. Left peripheral vestibular hypofunction was confirmed acutely on video head impulse testing, and pure tone audiometry showed a profound left sensorineural hearing loss. An MRI brain including diffusion-weighted imaging within 24 hours was normal. Delayed MRI brain and internal acoustic canal after 7 days demonstrated increased 3D fluid-attenuated inversion recovery and T1 signal throughout the left cochlea and semicircular canals, without contrast enhancement. This was consistent with labyrinthine haemorrhage. She received early oral prednisone followed by three doses of intratympanic dexamethasone. At 12 months follow-up the patient remained profoundly deaf, however, balance and vestibular symptoms improved with early vestibular physical rehabilitation.

Conclusion

We report a case of acute labyrinthine haemorrhage missed on an early MRI brain sequence. This diagnosis should be considered in presentations of acute audiovestibular loss, and delayed MRI including internal auditory canal sequences may be important for diagnosis.

Advanced Magnetic Resonance Imaging Sheds Light on the Distinct Pathophysiology of Various Types of Acute Sensorineural Hearing Loss

OBJECTIVE

To compare the findings of magnetic resonance imaging (MRI) with advanced protocols in patients with various types of acute sensorineural hearing loss (ASNHL).

STUDY DESIGN

Retrospective case review.

SETTING

Tertiary referral center.

PATIENTS

Two hundred eighty-seven patients with ASNHL.

INTERVENTIONS

All patients underwent MRI scanning, including heavily T2-weighted three-dimensional fluid-attenuated inversion recovery before and 4 hours after the intravenous administration of gadolinium contrast medium (delayed 3D-FLAIR). A hybrid of the reversed image of the positive endolymph signal and the native image of the perilymph signal image was constructed to visualize the endolymphatic space.

RESULTS

The detection rates of abnormal MRI findings vary significantly among different types of ASNHL. A hyperintense signal on delayed 3D-FLAIR was observed in all patients with intralabyrinthine schwannoma or vestibular schwannoma and 20.5% of patients with idiopathic sudden sensorineural hearing loss (ISSNHL) but was rarely observed in definite Ménière's disease (MD, 2.6%). In contrast, endolymphatic hydrops (EH) was frequently observed in patients with definite MD (79.5%) but was observed much less frequently in patients with ISSNHL (11.0%). In patients with cochlear MD and ALHL, detection rates of cochlear EH were similar to those with definite MD, whereas detection rates of vestibular EH were significantly lower than in patients with definite MD.

CONCLUSIONS

The significantly different detection rates of abnormal MRI findings among various types of ASNHL shed light on the distinct pathophysiology of each disorder. A diagnosis based on MRI findings with advanced protocols may help select treatment strategies and provide prognostic information for patients.

Vascular vertigo and dizziness: Diagnostic criteria

This paper presents diagnostic criteria for vascular vertigo and dizziness as formulated by the Committee for the Classification of Vestibular Disorders of the Bárány Society. The classification includes vertigo/dizziness due to stroke or transient ischemic attack as well as isolated labyrinthine infarction/hemorrhage, and vertebral artery compression syndrome. Vertigo and dizziness are among the most common symptoms of posterior circulation strokes. Vascular vertigo/dizziness may be acute and prolonged (≥24 hours) or transient (minutes to  < 24 hours). Vascular vertigo/dizziness should be considered in patients who present with acute vestibular symptoms and additional central neurological symptoms and signs, including central HINTS signs (normal head-impulse test, direction-changing gaze-evoked nystagmus, or pronounced skew deviation), particularly in the presence of vascular risk factors. Isolated labyrinthine infarction does not have a confirmatory test, but should be considered in individuals at increased risk of stroke and can be presumed in cases of acute unilateral vestibular loss if accompanied or followed within 30 days by an ischemic stroke in the anterior inferior cerebellar artery territory. For diagnosis of vertebral artery compression syndrome, typical symptoms and signs in combination with imaging or sonographic documentation of vascular compromise are required.

Labyrinthine lesions in presumed inner ear hemorrhage-related sudden deafness

PURPOSE

Inner ear hemorrhage (IEH) is a rare cause of sudden sensorineural hearing loss (SSNHL). This study aimed to evaluate the lesional patterns in patients with presumed IEH from morphological and functional aspects.

METHODS

Seventeen patients with SSNHL and presumed IEH who completed audio-vestibular tests were included. The main outcome measures included clinical characteristics, radiology, and functional test results.

RESULTS

The morphological findings and functional tests revealed differences in locations and lesional spectrums. The magnetic resonance imaging (MRI) hyperintensity was likely to involve the vestibule (88.2%), the cochlea (76.5%), and the posterior and lateral semicircular canals (76.5% and 70.6%, respectively). Furthermore, 70.6% of cases showed abnormality in the entire labyrinth, and abnormalities in the vestibule/semicircular canals were observed in 17.6% of cases. Meanwhile, dysfunction was sequentially detected in the cochlea (100%), semicircular canals (94.1%), and vestibule (70.6%); 64.7% of cases showed combined deficit in the entire labyrinth, and 29.4% of cases showed combined deficit in the cochlea/semicircular canals. Although lesions in the labyrinth were frequently detected, the results of the radiological and functional tests did not always match and significantly differed in either cochlear or superior semicircular canal damage detection (p < 0.05 each).

CONCLUSIONS

In this cohort, IEH preferentially caused sudden audio-vestibular impairment, which was well demonstrated by a combination of MRI and functional tests. The specific lesional configurations revealed in this study may suggest a possible pathomechanism that could be further explored as a therapeutic target.

Clinical usefulness of labyrinthine three-dimensional fluid-attenuated inversion recovery magnetic resonance images in idiopathic sudden sensorineural hearing loss

PURPOSE OF REVIEW

Literature on the use of current magnetic resonance imaging (MRI) for patients with idiopathic sudden sensorineural hearing loss (ISSNHL) is reviewed, emphasizing the role of three-dimensional fluid-attenuated inversion recovery (3D-FLAIR) MRI. The discussion focuses on the diagnostic role of temporal bone MRI using 3D-FLAIR and the relationship between MRI findings, clinical symptoms, and hearing outcome.

RECENT FINDINGS

The currently suggested MRI protocol for SSNHL includes a 3D T2-weighted steady-state free procession sequence or its equivalent, pre and postcontrast T1-weighted, and pre and postcontrast 3D-FLAIR sequences. The 3D-FLAIR image identifies an underlying labyrinthine condition in 24-57% of patients with ISSNHL, contributing to understanding the pathophysiologic mechanisms (e.g., labyrinthitis or labyrinthine hemorrhage). Recent studies demonstrated consistent results that initial hearing loss could be related to the signal change on the 3D-FLAIR image. Various results on 3D-FLAIR image value prediction for the final hearing outcome were shown.

SUMMARY

3D-FLAIR MRI application identifies an underlying labyrinthine condition. Abnormal MRI findings correlate with initial hearing loss and accompanying symptoms and hearing outcome. Performing temporal bone MRI with 3D-FLAIR sequence may clarify probable ISSNHL pathophysiology, improve diagnostic accuracy, provide prognostic information to physicians, and possibly guide toward a more specific treatment.

Diagnostic value of 3D-FLAIR MRI in children with sudden deafness caused by inner ear hemorrhage

Objective

To investigate the diagnostic value of three-dimensional fluid-attenuated inversion recovery (3D-FLAIR) MRI in children with sudden deafness caused by inner ear hemorrhage.

Methods

The diagnostic efficacies of three different MRI sequences in the examination of the inner ear for 32 children with sudden deafness were compared. Hearing examination results and 3-month follow-up outcomes were analyzed.

Results

The age of 32 children with sudden deafness ranged from 5 to 18 years. MRI was performed from 1 to 18 days after onset. Six cases of sudden deafness caused by inner ear hemorrhage were finally diagnosed clinically. For different MRI sequences, the 3D-FLAIR sequence detected five positive cases; the conventional T1-weighted image sequence also detected five positive cases; but the conventional T2-weighted image sequence only detected three positive cases. The sensitivity and specificity of the 3D-FLAIR sequence in the diagnosis of inner ear hemorrhage were 83.3% (5/6) and 96.2% (25/26), respectively, and the area under the curve value of the receiver operating characteristic curve was 0.897. In the hemorrhage group, all six cases had extremely severe sensorineural hearing loss, and the hearing recovery was ineffective after 3 months of follow-up. The degree of hearing impairment, 3-month short-term treatment efficacy, and 3D-FLAIR MRI in the diagnosis of inner ear hemorrhage between hemorrhage group and non-hemorrhage group were statistically significant (p=0.043, p=0.000, p=0.000).

Conclusions

3D-FLAIR MRI is helpful for the diagnosis of inner ear hemorrhage in children with sudden deafness. Besides, short-term treatment indicates poor effects on children with severe hearing impairment.

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.

The prognostic value and pathophysiologic significance of three-dimensional fluid-attenuated inversion recovery (3D-FLAIR) magnetic resonance imaging in idiopathic sudden sensorineural hearing loss: A systematic review and meta-analysis

BACKGROUND

The underlying pathophysiology of idiopathic sudden sensorineural hearing loss (ISSNHL) is still unknown. However, an increasing number of observational studies report intralabyrinthine signal alterations in patients with ISSNHL using three-dimensional fluid-attenuated inversion recovery (3D-FLAIR) magnetic resonance imaging (MRI). These findings warrant a meta-analysis.

OBJECTIVE OF REVIEW

To conduct a meta-analysis assessing the value of 3D-FLAIR MRI in identifying possible underlying labyrinthine pathophysiologic mechanisms and prognostication in patients with ISSNHL.

SEARCH STRATEGY

Two reviewers independently searched the Pubmed, Embase and Cochrane Library from inception until October 10, 2018 and evaluated eligibility based on titles and abstracts of all retrieved studies. All studies reporting on 3D-FLAIR imaging in ISSNHL were included. Subsequently, the full text of eligible studies were evaluated.

EVALUATION METHOD

Adhering to the MOOSE guideline, two independent reviewers extracted data, assessed risk of bias and evaluated the relevance and quality of evidence. Data on the number of patients and events were extracted and hearing levels were converted to standardised mean differences (SMD) for conducting meta-analyses. Random effects models for meta-analyses were applied.

RESULTS

Eight observational studies met our inclusion criteria (n = 638 patients). In 29%, high signal intensity was found on 3D-FLAIR imaging, suggesting labyrinthine pathology (labyrinthitis [79%], intralabyrinthine haemorrhage [21%]). High signal intensity on 3D-FLAIR was associated with poorer hearing (SMD: 14 dB, 95% CI 5.67-22.94) and vertigo (RR: 1.92, 95% CI 1.16-3.17) at baseline. Multivariate analyses demonstrated that patients with high 3D-FLAIR signal intensity had 21 dB lower final hearing pure-tone averages (SMD: 21 dB, 95% CI 9.08-33.24).

CONCLUSIONS

Three-dimensional fluid-attenuated inversion recovery MR imaging can identify an underlying labyrinthine condition in up to 29% of patients with sudden hearing loss in whom previously no cause could be identified. Their final pure-tone averages are more than 20 dB worse than 3D-FLAIR-negative patients, suggesting more severe labyrinthine damage. Findings such as these may contribute to our understanding of pathophysiologic mechanisms of ISSNHL.

The Natural History of Labyrinthine Hemorrhage in Patients With Sudden Sensorineural Hearing Loss

To investigate the application of inner ear 3-dimensional fluid-attenuated inversion recovery (3D-FLAIR) magnetic resonance imaging (MRI) in patients with sudden sensorineural hearing loss (SSNHL) accompanied by inner ear hemorrhage. A total of 1252 SSNHL patients who were admitted from January 2010 to April 2018 were included in the study. The patients' clinical features, complete blood counts, coagulation profiles, audiometry data, and MRI scans were retrospectively reviewed. Twenty-four patients had high labyrinth signals on inner ear 3D-FLAIR MRI (24/1252, 1.9%) that were diagnosed as inner ear hemorrhage. One patient had endolymphatic hydrops on the contralesional side. In the 24 patients, pure tone audiometry curves revealed profound deafness (19/24) and flat moderate hearing loss (5/24); most patients had associated vertigo (23/24) and tinnitus (19/24). Patients with SSNHL (N = 24) were treated. Sixteen patients had invalid improvement, 3 patients were markedly improved, 4 patients had effective treatment, and only 1 patient was cured, for a therapeutic efficacy of 33.3% (8/24). Follow-up 3D-FLAIR MRI in patients showed absorbance of labyrinthine hemorrhage and disappearance of the high signal intensity in the inner ear within 2 weeks to 4 months. Inner ear 3D-FLAIR MRI indicate that most cases of inner ear hemorrhage are spontaneous and that high labyrinth signals are absorbed within 4 months. The site of labyrinth hemorrhage is irregular and independent of hearing loss. Conventional treatment is not very effective, and an appropriate therapy for SSNHL requires further investigation.

Audiological outcomes in sudden sensorineural hearing loss with presumed inner ear hemorrhage

OBJECTIVE

To explore the hearing outcomes and prognostic factors in patients with sudden sensorineural hearing loss resulting from inner ear hemorrhage.

METHODS

42 patients (22 male and 20 female) were recruited from January 2016 to December 2017. Intravenous methylprednisolone and/or intratympanic corticosteroid were used as salvage therapy. The main measures included systemic risk factors and audiometric outcomes as proposed by American Academy of Otolaryngology-Head and Neck Surgery Hearing Loss Scale. All individuals were assessed at baseline, discharge (2 weeks post-treatment) and at 1, 3 and 6 months.

RESULTS

The mean ages of patients were 39.3 ± 14.8 yrs. Cardiovascular disorders were seen in 19.0-33.3% of cases. Restoration of hearing and speech discrimination abilities were assessed at the first month post-treatment versus initial levels (95.5 ± 15.5 vs. 109.2 ± 9.6 dB, p = 0.000; and 17.6 ± 24.4 vs. 1.3 ± 4.0%, p = 0.003, respectively). Word recognition scores continued to recover at month 6 (38.7 ± 35.4%, p = 0.000), whereas puretone ceased to change (90.8 ± 16.2 dB, p = 0.139). The final percentages of complete, partial and no recovery were 0%, 57.1% and 42.9% respectively. The prognosis was independent of accompanying systemic risk factors as analyzed in this study. Intratympanic intervention was associated with improved word recognition scores, although intravenous corticosteroid was not.

CONCLUSIONS

Profound sudden sensorineural hearing loss caused by inner ear hemorrhage often has an unsatisfactory prognosis. However, this cohort did experience partial audiological recovery with delayed onset. Immediate and effective intratympanic corticosteroid may have therapeutic potential for this intractable disease.

Delayed Recovery in Pediatric Sudden Sensorineural Hearing Loss Predicted via Magnetic Resonance Imaging

Objectives:

To evaluate the potential origins via magnetic resonance imaging and the relevant hearing recovery course of pediatric sudden sensorineural hearing loss.

Methods:

We retrospectively analyzed data of 25 pediatric patients from our center with sudden sensorineural hearing loss from January 2011 to December 2016. All individuals were closely followed up at baseline and 1 and 6 months.

Results:

Magnetic resonance imaging identified presumed causes in 9 cases, 5 of which showed intralabyrinthine hyperintensity, suggesting presumptive intralabyrinthine hemorrhage. The remaining 20 patients showed no hyperintensity. Restoration of hearing and speech discrimination abilities were noted in these 25 children at 6 months versus the initial levels (74.2 ± 22.6 vs 93.5 ± 20.5 dB, p = .000, and 45.8 ± 36.0 vs. 18.3 ± 22.1%, p = .004, respectively). The prognosis of the individuals with intralabyrinthine hemorrhage were superior in terms of frequency and hearing threshold at 6 months compared with that of the no-hemorrhage participants. Word recognition scores improved in either studied group.

Conclusion:

The potential recovery of hearing in children raises concerns about very early surgical intervention within the first 6 months. Rational imaging and sequential audiometric evaluation to monitor the progression of recovery may be beneficial.