MRI Evaluation of Vestibular Endolymphatic Space in Patients with Isolated Cystic Lateral Semicircular Canal Malformation

Isolated lateral semicircular canal dysplasia (LSCCD) is one of the most frequent malformations of the bony labyrinth. The aim of this study is to depict morphology and size of the vestibular endolymphatic space in patients with isolated LSCCD using a dedicated 3D high resolution MR sequence called 3D inversion recovery with REAL reconstruction (3D-REAL-IR). From January 2018 to February 2020, we reviewed 281 CT and 241 MR temporal bone studies, and 103 MR studies performed for the evaluation of endolymphatic hydrops (EH). Five patients with LSCCD were found, one of them with bilateral malformation. Three patients (four affected ears) underwent specific MR examination for the evaluation of EH, consisting of a heavily T2-weighed cisternography sequence (T2 SPACE) and a 3D inversion-recovery with REAL reconstruction. The endolymphatic volumetric ratio (ELR) was calculated as the total endolymphatic volume divided by the total lymph (vestibular) volume multiplied by 100. Hydrops MR imaging was available in four of the affected ears. ELR ranged from 22% to 81%. Both extremes were present in the same patient, corresponding to a patient with right unilateral Ménière’s syndrome but with bilateral LSCCD. A patient affected with hearing loss had an ELR of 33% and the last patient with unilateral probable Ménière’s syndrome showed an ELR of 42%. Endolymphatic hydrops imaging is feasible and can be performed on patients with inner ear malformations like LSCCD. The endolymphatic volumetric ratio could be a useful and reproducible tool in daily clinical practice.

Download Full-text

Unilateral Horizontal Semicircular Canal Malformation Causing Recurrent Vertigo

Philippine Journal of Otolaryngology Head and Neck Surgery ◽

10.32412/pjohns.v32i2.87 ◽

2018 ◽

Vol 32 (2) ◽

pp. 58-59

Author(s):

Nathaniel W. Yang

Keyword(s):

Hearing Loss ◽

Inner Ear ◽

Temporal Bone ◽

Semicircular Canal ◽

Lateral Semicircular Canal ◽

Vestibular Loss ◽

Vestibular Neurectomy ◽

Horizontal Semicircular Canal ◽

Ear Malformations ◽

Vestibular Symptoms

A 62-year-old man consulted for recurrent episodes of vertigo lasting from seconds to several minutes. The vertigo was variably described as spinning, lateral swaying, and a feeling of being “unsure of his position in space.” These episodes were noted to have begun when the patient was still in his 20’s. Standard pure tone audiometry revealed a mild-to-moderate downsloping mixed hearing loss in the left ear. Bithermal caloric testing indicated the presence of a significant left-sided peripheral vestibular loss. Due to the fact that the vertigo episodes presented relatively early in life, the possibility of a congenital inner ear malformation was considered as a cause for his symptoms. Computerized tomographic (CT) imaging of the temporal bone was performed. This clearly showed the left horizontal semicircular canal lacking a central bony island. (Figure 1 and 2) The cochlea, superior and posterior semicircular canals, vestibular and cochlear aqueducts, and ossicular chain were grossly normal. A malformation of the horizontal or lateral semicircular canal is one of the most common inner ear malformations, as it is the last vestibular structure to be formed during inner ear embryogenesis. As such, it may occur in isolation or may be associated with other vestibular, cochlear, or middle ear malformations.1,2 Although vertigo and dizziness are symptoms to be expected in such a condition, existing data indicates that it may be totally asymptomatic, or it may also present as a sensorineural, conductive, or mixed type of hearing loss.1,3 Radiologic imaging is of prime importance in diagnosing such conditions, especially when auditory and/or vestibular symptoms manifest early in life. This case perfectly illustrates the need for such studies, as the patient went undiagnosed for more than forty years! No definitive statements can be gleaned from existing medical literature with respect to treatment. However, in patients with debilitating vestibular symptoms, management with modalities that selectively target the vestibular system, but spare the auditory system, such as vestibular neurectomy and trans-tympanic aminoglycoside therapy appear to be reasonable options. References Johnson J, Lalwani AK. Sensorineural and conductive hearing loss associated with lateral semicircular canal malformation. Laryngoscope 2000 Oct;110(10):1673–1679. DOI:10.1097/00005537-200010000-00019 PMID: 11037823 Casselman JW, Delanote J, Kuhweide R, van Dinther J, De Foer B, Offeciers EF. Congenital malformations of the temporal bone. In: Lemmerling M, De Foer B, editors. Temporal bone imaging. Berlin Heidelberg: Springer-Verlag; 2015, pp. 120-154. Kim CH, Shin JE, Lee YJ, Park HJ. Clinical characteristics of 7 patients with lateral semicircular canal dysplasia. Res Vestib Sci 2012;11(2):64-68.

Download Full-text

Partial Duplication of the Lateral Semicircular Canal—A Novel Anatomical Malformation in a Child with Barakat Syndrome

Journal of Pediatric Neurology ◽

10.1055/s-0041-1740366 ◽

2021 ◽

Author(s):

Varun Kannan ◽

Brandon Tran

Keyword(s):

Hearing Loss ◽

Inner Ear ◽

Semicircular Canal ◽

Sensorineural Deafness ◽

Anatomical Variations ◽

Lateral Semicircular Canal ◽

Partial Duplication ◽

Posterior Limb ◽

Ear Malformations ◽

Ear Anomalies

AbstractSeveral known genetic causes of sensorineural deafness are associated with dysplasia of inner ear structures, including the cochlea and labyrinth. Here, we present a child with Barakat syndrome and sensorineural hearing loss, found to have multiple inner ear anomalies including partial duplication of the posterior limb of the left lateral semicircular canal. To our knowledge, duplication of the semicircular canal has not previously been reported. This finding expands our understanding of the range of anatomical variations observed in congenital inner ear malformations, and further characterizes the phenotypic manifestations of Barakat syndrome.

Download Full-text

Bilateral, isolated, lateral semicircular canal malformation without hearing loss

The Journal of Laryngology & Otology ◽

10.1017/s0022215108002740 ◽

2008 ◽

Vol 122 (8) ◽

pp. 858-860 ◽

Cited By ~ 8

Author(s):

I Dallan ◽

S Berrettini ◽

E Neri ◽

A P Casani

Keyword(s):

Hearing Loss ◽

Inner Ear ◽

Semicircular Canal ◽

Imaging Techniques ◽

Three Dimensional ◽

Lateral Semicircular Canal ◽

Normal Limits ◽

Dimensional Reconstruction ◽

Ear Malformations ◽

Molecular Aspects

AbstractHypothesis:Inner-ear malformations are frequently found in patients with sensorineural hearing loss. However, isolated anomalies of the vestibular part of the inner ear are seldom described, and for this reason their impact on balance is poorly understood.Care report:We present the case of a 38-year-old Caucasian man with recurrent vestibular complaints, with a sensation of linear tilting, but no hearing impairment. Clinical and neuro-otological examinations showed peripheral involvement of the vestibular system, while audiological investigation was within normal limits. High-resolution magnetic resonance imaging of the inner ear, with three-dimensional reconstruction, demonstrated isolated vestibular anomalies involving both the lateral semicircular canal and the utricle.Conclusions:Bearing in mind this case, we speculate that isolated vestibular malformation may not be as rare as previously thought, and should be investigated with the aid of sophisticated imaging techniques. A review of the relative literature, focussing attention on the molecular aspects, is also reported.

Download Full-text

A test of the lateral semicircular canal correlation to head posture, diet and other biological traits in “ungulate” mammals

Scientific Reports ◽

10.1038/s41598-020-76757-0 ◽

2020 ◽

Vol 10 (1) ◽

Author(s):

J. Benoit ◽

L. J. Legendre ◽

A. A. Farke ◽

J. M. Neenan ◽

B. Mennecart ◽

...

Keyword(s):

Semicircular Canal ◽

Ct Scanning ◽

Biological Traits ◽

Large Sample Size ◽

Strongly Correlated ◽

Lateral Semicircular Canal ◽

Extinct Species ◽

Head Posture ◽

Bony Labyrinth ◽

Phylogenetic Regression

Abstract For over a century, researchers have assumed that the plane of the lateral semicircular canal of the inner ear lies parallel to the horizon when the head is at rest, and used this assumption to reconstruct head posture in extinct species. Although this hypothesis has been repeatedly questioned, it has never been tested on a large sample size and at a broad taxonomic scale in mammals. This study presents a comprehensive test of this hypothesis in over one hundred “ungulate” species. Using CT scanning and manual segmentation, the orientation of the skull was reconstructed as if the lateral semicircular canal of the bony labyrinth was aligned horizontally. This reconstructed cranial orientation was statistically compared to the actual head posture of the corresponding species using a dataset of 10,000 photographs and phylogenetic regression analysis. A statistically significant correlation between the reconstructed cranial orientation and head posture is found, although the plane of the lateral semicircular canal departs significantly from horizontal. We thus caution against the use of the lateral semicircular canal as a proxy to infer precisely the horizontal plane on dry skulls and in extinct species. Diet (browsing or grazing) and head-butting behaviour are significantly correlated to the orientation of the lateral semicircular canal, but not to the actual head posture. Head posture and the orientation of the lateral semicircular canal are both strongly correlated with phylogenetic history.

Download Full-text

The Surgical Management of Labyrinthine Fistulae in Chronic Otitis Media with Cholesteatoma

Annals of Otology Rhinology & Laryngology ◽

10.1177/00034894740830s101 ◽

1974 ◽

Vol 83 (1_suppl) ◽

pp. 1-19 ◽

Cited By ~ 22

Author(s):

Richard R. Gacek

Keyword(s):

Hearing Loss ◽

Sensorineural Hearing Loss ◽

Otitis Media ◽

Surgical Management ◽

Semicircular Canal ◽

Chronic Otitis Media ◽

Semicircular Canals ◽

Sensorineural Hearing ◽

Large Area ◽

Bony Labyrinth

The author's series of 168 consecutive cases of chronic otitis media from the years 1965 to 1972 were reviewed with regard to the occurrence and management of pathological fistulae in the bony labyrinth. Fourteen cases (incidence 8.3%), of which nine involved only the semicircular canals and five involved primarily the cochlear wall occasionally associated with a semicircular canal fistula, were examined particularly in terms of postoperative sensorineural hearing loss following removal of cholesteatoma matrix from the fistula. The results indicated that the matrix can be removed with reasonable safety from most small semicircular canal fistulae. Only when the cholesteatoma matrix is firmly adherent to a large area of membranous semicircular canal is removal not recommended. When the cholesteatoma was removed from three cochlear fistulae, sensorineural hearing loss resulted. In two cases with cochlear fistula, hearing was preserved when the cholesteatoma matrix was not removed from the fistulized area. These results have been used to formulate guidelines for the surgical management of pathological fistulae of the bony labyrinth.

Download Full-text

Inner ear Hemorrhage and Endolymphatic Hydrops in a Leukemic Patient with Sudden Hearing Loss

Annals of Otology Rhinology & Laryngology ◽

10.1177/000348947708600412 ◽

1977 ◽

Vol 86 (4) ◽

pp. 518-524 ◽

Cited By ~ 33

Author(s):

Isamu Sando ◽

Tetsuya Egami

Keyword(s):

Hearing Loss ◽

Endolymphatic Hydrops ◽

Stria Vascularis ◽

Organ Of Corti ◽

Sudden Hearing Loss ◽

Lymphocytic Leukemia ◽

Endolymphatic Sac ◽

New Bone Formation ◽

Vestibular Aqueduct ◽

Endolymphatic Space

Several significant histopathological findings were noted in a case of sudden hearing loss in a patient with chronic lymphocytic leukemia. The major pathological findings were leukemic hemorrhage into both perilymphatic and endolymphatic spaces in the cochlear and vestibular systems, endolymphatic hydrops in the cochlea and sacculus, and a relatively narrowed and straightened vestibular aqueduct and endolymphatic sac. Additional interesting findings include: loss of hair cells in the organ of Corti and vestibular end-organs; destruction of the stria vascularis (possibly the origin of the blood); fibrosis in the perilymphatic spaces in the cochlea and the vestibule, and in the endolymphatic space in the vestibule; and new bone formation in the perilymphatic spaces in the vestibule. The leukemic infiltrate observed in both the cochlea and the vestibule was not considered to be significant. Hemorrhage into the cochlea is thought to be the most reasonable cause of the sudden hearing loss in this case. Also discussed are fibrosis and osteogenesis as a late consequence of hemorrhage, and the coexistence of endolymphatic hydrops with an anomaly of the vestibular aqueduct and endolymphatic sac.

Download Full-text

Sensorineural and Conductive Hearing Loss Associated With Lateral Semicircular Canal Malformation

The Laryngoscope ◽

10.1097/00005537-200010000-00019 ◽

2000 ◽

Vol 110 (10) ◽

pp. 1673-1679 ◽

Cited By ~ 30

Author(s):

Jacob Johnson ◽

Anil K. Lalwani

Keyword(s):

Hearing Loss ◽

Semicircular Canal ◽

Conductive Hearing Loss ◽

Lateral Semicircular Canal ◽

Conductive Hearing

Download Full-text

Audiological and Vestibular Functions in Patients With Lateral Semicircular Canal Dysplasia and Aplasia

Clinical and Experimental Otorhinolaryngology ◽

10.21053/ceo.2019.01053 ◽

2020 ◽

Vol 13 (3) ◽

pp. 255-260 ◽

Cited By ~ 1

Author(s):

Sang Hyun Kwak ◽

Min Ki Kim ◽

Sung Huhn Kim ◽

Jinsei Jung

Keyword(s):

Hearing Loss ◽

Inner Ear ◽

Semicircular Canal ◽

Pure Tone ◽

Lateral Semicircular Canal ◽

Vestibular Loss ◽

Horizontal Canal ◽

Canal Paresis ◽

Bilateral Hearing Loss ◽

Ear Anomalies

Objectives. The aim of the present study was to evaluate audiologic and vestibular functions in patients with lateral semicircular canal (LSCC) dysplasia/aplasia.Methods. We conducted a retrospective study of a patients with LSCC dysplasia and aplasia at tertiary referral center. The subjects included 15 patients with LSCC dysplasia or aplasia, with or without combined inner ear anomalies. Medical history, temporal bone computed tomography scans, pure-tone audiograms, and vestibular function test results were analyzed.Results. LSCC anomaly was identified in 15 patients (20 ears). Nine patients had unilateral LSCC dysplasia only and showed a mean pure-tone average of 45.5±28.7 dB, while three patients (33.3%) among them had normal hearing. Six patients had bilateral LSCC dysplasia/aplasia combined with other inner ear anomalies and profound bilateral hearing loss. Notably, only four out of 15 patients (26.7%) had dizziness symptoms. On caloric test, patients with isolated LSCC dysplasia showed a 51.8%±29.3% level of canal paresis (eight out of nine patients showed anomalies), whereas patients with bilateral LSCC dysplasia/aplasia presented bilateral vestibular loss. One patient with isolated LSCC underwent video-head impulse test; horizontal canal gain decreased to 0.62 (17% asymmetry) and anterior canal gain was 0.45 (52.6% asymmetry), whereas posterior canal gain was normal.Conclusion. Bilateral LSCC dysplasia/aplasia is comorbid with other inner ear anomalies and presents as profound bilateral hearing loss and vestibulopathy. In contrast, isolated unilateral LSCC dysplasia presents as ipsilateral horizontal canal paresis. Hearing function in isolated LSCC dysplasia is usually, but not always, impaired with varying severity.

Download Full-text