home : about us : ahead of print : current issue : archives search instructions : subscriptionLogin 
Users online: 301      Small font sizeDefault font sizeIncrease font size Print this page Email this page

Previous Article  Table of Contents  Next Article  
NEUROIMAGING
Ahead of print publication
 

Dandy–Walker malformation presenting with hearing loss: A unique imaging diagnosis


1 Present address: Department of Radiodiagnosis, Post Graduate Institute of Medical Education and Research (PGIMER), Sector 12, Chandigarh, India
2 Department of Radiodiagnosis, Government Medical College and Hospital, Sector 32, Chandigarh, India

Date of Submission16-Dec-2020
Date of Decision18-Dec-2020
Date of Acceptance29-Dec-2020
Date of Web Publication12-Jul-2021

Correspondence Address:
Harsimran Bhatia,
Department of Radiodiagnosis, Post Graduate Institute of Medical Education and Research (PGIMER), Sector 12, Chandigarh.
India
Login to access the Email id

Source of Support: None, Conflict of Interest: None

DOI: 10.4103/jpn.JPN_321_20

 

   Abstract 

Dandy–Walker malformation (DWM) is a common congenital posterior fossa anomaly, however, its association with concomitant bilateral inner ear anomalies has been rarely reported so far. We present such a case that showed characteristic imaging features of DWM along with uncommon vestibulocochlear anomalies like cochlear hypoplasia and Internal Auditory Canal atresia.


Keywords: Cochlear hypoplasia, Dandy–Walker malformation, internal auditory canal (IAC) atresia, inner ear anomalies, macrocephaly



How to cite this URL:
Bhatia H, Aggarwal P. Dandy–Walker malformation presenting with hearing loss: A unique imaging diagnosis. J Pediatr Neurosci [Epub ahead of print] [cited 2021 Nov 28]. Available from: https://www.pediatricneurosciences.com/preprintarticle.asp?id=321166




A 3-year-old boy presented to the pediatric OPD with complaints of decreased hearing since birth and delayed motor milestones. Perinatal period was insignificant. Examination revealed an enlarged head circumference and bilateral profound sensorineural hearing loss (SNHL) on audiometry.

Magnetic resonance imaging (MRI) brain revealed a cystically enlarged posterior fossa communicating with a dilated fourth ventricle and a hypoplastic cerebellar vermis. An occipital bone defect was noted along with a high cervical meningocele. There was gross hydrocephalus along with severe thinning of the corpus callosum [Figure 1]. Features on MRI suggested a diagnosis of Dandy–Walker malformation (DWM). High-resolution computerized tomography (HRCT) of the temporal bone, however, revealed interesting unexpected findings. There were multiple anomalies involving bilateral (B/L) inner ear structures. The cochlea was hypoplastic bilaterally, consisted of less than two turns, and had an absent modiolus. Labyrinthine segment of the facial canal was anteriorly displaced with an atretic (absent) Internal Auditory Canal on the right. While the vestibule and semicircular canals (SCC) were absent on right, the left vestibule was dilated and fused with a dysplastic appearing lateral SCC (that lacked a normal bony island) [Figure 2].
Figure 1: A: Axial T2W MRI showing cystically dilated posterior fossa (red arrow) communicating with a dilated fourth ventricle (blue arrow); B: Sagittal T2W MRI showing gross hydrocephalus with thinned out corpus callosum (yellow arrow), hypoplastic cerebellar vermis (blue arrow), and high cervical meningocele (red arrow); C: Axial HRCT temporal bone showing the occipital bony defect (blue arrow)

Click here to view
Figure 2: A: Coronal HRCT section: Less than two turns of the cochlea bilaterally (red arrows); B, C: Axial sections (Magnified views) of inner ears, B: Right inner ear: Hypoplastic cochlea (red arrow) with the absence of ipsilateral vestibule, SCCs, and IAC (yellow arrow); anteriorly displaced facial canal (blue arrow); C: Left inner ear: Dilated vestibule fused with dysplastic lateral SCC (yellow arrow), hypoplastic cochlea (red arrow), and normal IAC (blue arrow)

Click here to view


DWM is a common congenital posterior fossa anomaly, presenting with macrocephaly in the first few months of life.[1],[2] Characteristic imaging features help clinch a definitive diagnosis.[3] Although often associated with concomitant brain abnormalities, association with inner ear anomalies has been rarely reported.

SNHL is a major cause of childhood disability worldwide, with an estimated prevalence of 1 in 2000 neonates and inner ear malformations, accounting for about 5–15% of these cases.[4],[5] Cochlear hypoplasia with internal auditory canal (IAC) atresia in itself is an uncommon entity[6] and its association with DWM, is indeed a unique imaging diagnosis. HRCT with its 3D reconstruction algorithm and high spatial resolution, not only delineates the bony labyrinth anatomy, instead, facial canal course, middle ear status, and mastoid pneumatisation are also well depicted, thus predicting feasibility for cochlear implantation [Figure 3].[7] Due to the gross degree of malformations observed, the child was not considered a suitable candidate for the same and was advised to use conventional hearing aids.[8]
Figure 3: Normal inner ear anatomy, magnified views of the axial HRCT temporal bone sections. A: Axial section of left inner ear showing a normal lateral SCC with a bony island within (red arrow) and vestibule (yellow arrow); B: Axial section of right inner ear showing: normal trifoliate cochlea with a modiolus (red arrow) and normal IAC (blue arrow); C: Coronal HRCT section showing: Normal turns of the left cochlea (red arrow) and normal right SCCs (yellow arrow)

Click here to view


Financial support and sponsorship

Nil.

Conflicts of interest

There are no conflicts of interest.



 
   References Top

1.
Doherty D, Millen KJ, Barkovich AJ. Midbrain and hindbrain malformations: advances in clinical diagnosis, imaging, and genetics. Lancet Neurol 2013;12:381-93.  Back to cited text no. 1
    
2.
Alexiou GA, Sfakianos G, Prodromou N. Dandy-Walker malformation: analysis of 19 cases. J Child Neurol 2010;25:188-91.  Back to cited text no. 2
    
3.
Bosemani T, Orman G, Boltshauser E, Tekes A, Huisman TA, Poretti A. Congenital abnormalities of the posterior fossa. Radiographics 2015;35:200-20.  Back to cited text no. 3
    
4.
Billings KR, Kenna MA. Causes of pediatric sensorineural hearing loss: yesterday and today. Arch Otolaryngol Head Neck Surg 1999;125:517-21.  Back to cited text no. 4
    
5.
Mafee MF, Selis JE, Yannias DA, Valvassori GE, Pruzansky S, Applebaum EL, et al. Congenital sensorineural hearing loss. Radiology 1984;150:427-34.  Back to cited text no. 5
    
6.
Sennaroglu L, Saatci I. A new classification for cochleovestibular malformations. Laryngoscope 2002;112:2230-41.  Back to cited text no. 6
    
7.
Joshi VM, Navlekar SK, Kishore GR, Reddy KJ, Kumar EC. CT and MR imaging of the inner ear and brain in children with congenital sensorineural hearing loss. Radiographics 2012;32:683-98.  Back to cited text no. 7
    
8.
Ramos A, Cervera J, Valdivieso A, Pérez D, Vasallo JR, Cuyas JM. Cochlear implant in congenital malformations. Acta Otorrinolaringol Esp 2005;56:343-8.  Back to cited text no. 8
    


    Figures

  [Figure 1], [Figure 2], [Figure 3]



 

Top
 
Previous Article   Next Article

    

 
  Search
 
   Ahead of print
  
 
     Search Pubmed for
 
    -  Bhatia H
    -  Aggarwal P


    Abstract
    References
    Article Figures

 Article Access Statistics
    Viewed375    
    PDF Downloaded4    

Recommend this journal