• Users Online: 54
  • Print this page
  • Email this page

Table of Contents
Year : 2020  |  Volume : 8  |  Issue : 2  |  Page : 92-93

When you find a tooth in the brain, call joubert for help

Department of Neurology, Bangalore Medical College and Research Institute, Bengaluru, Karnataka, India

Date of Submission21-Dec-2019
Date of Acceptance18-Jan-2020
Date of Web Publication18-Apr-2020

Correspondence Address:
Dr. Suhas Murali
Department of Neurology, PMSSY-Super Specialty Hospital, Victoria Hospital Campus, Bangalore Medical College and Research Institute, Fort Road, Bengaluru - 560 002, Karnataka
Login to access the Email id

Source of Support: None, Conflict of Interest: None

DOI: 10.4103/AJIM.AJIM_92_19

Rights and Permissions

Joubert syndrome is an extremely rare autosomal recessive condition characterized by agenesis of the cerebellar vermis. This has characteristic imaging features which have been described in this article.

Keywords: Batwing sign, Joubert syndrome, molar tooth sign

How to cite this article:
Murali S, Nagraj K. When you find a tooth in the brain, call joubert for help. APIK J Int Med 2020;8:92-3

How to cite this URL:
Murali S, Nagraj K. When you find a tooth in the brain, call joubert for help. APIK J Int Med [serial online] 2020 [cited 2020 Jul 5];8:92-3. Available from: http://www.ajim.in/text.asp?2020/8/2/92/282853

  Clinical Image Description Top

Joubert syndrome is an extremely rare autosomal recessive condition, which causes cerebellar vermis agenesis.[1] The phenotypic features include nystagmus, global developmental delay, breathing abnormalities, hypotonia, and oculomotor apraxia.[2],[3] Extraneural manifestations include retinal coloboma and multicystic kidney disease. Hence, some consider it as part of a wider cerebello-oculo-renal syndrome.[4],[5] It is an extremely rare disorder with an estimated incidence of one in 100,000 live births. It was first described by Dr. Marie Joubert in 1969, a pediatric neurologist. They described a family of four siblings in a French Canadian family, with consanguinity traced back to 11 generations.[6] Here, we describe the characteristic imaging feature of this rare condition.

Imaging in Joubert syndrome shows the presence of:

  1. A gross cerebellar vermis agenesis
  2. Thin and elongated superior cerebellar peduncle (SCP) = “molar tooth”[7],[8] As shown in [Figure 1] with comparative normal in [Figure 2]
  3. Deep interpeduncular fossa (along with first and second features mentioned above) gives rise to a “bat wing fourth ventricle” (not so classically seen in our case)
  4. On diffusion tensor imaging, evidence of absence of fiber decussation in the SCP
  5. Dysplasia and heterotopia of cerebellar nuclei
  6. Abnormal inferior olivary nuclei
  7. Corpus callosal dysgenesis
  8. Lateral ventricle enlargement.[9]
Figure 1: The classical “molar tooth” sign in Joubert syndrome

Click here to view
Figure 2: Normal T1-weighted axial magnetic resonance image at the level of the superior cerebellar peduncle. This image shows how a normal cerebellar vermis looks along with the length of the superior cerebellar peduncles and the interpeduncular fossa depth

Click here to view

Among these, the first three in the list are more commonly seen compared to the latter three. As described in our case in [Figure 3].
Figure 3: The features which are characteristic of Joubert syndrome

Click here to view

This clinical image is to shed light on this classical appearance of this rare condition.

Financial support and sponsorship


Conflicts of interest

There are no conflicts of interest.

  References Top

Parisi MA. Clinical and molecular features of Joubert syndrome and related disorders. Am J Med Genet C Semin Med Genet 2009;151C: 326-40.  Back to cited text no. 1
Parisi MA, Doherty D, Chance PF, Glass IA. Joubert syndrome (and related disorders) (OMIM 213300). Eur J Hum Genet 2007;15:511-21.  Back to cited text no. 2
Maria BL, Boltshauser E, Palmer SC, Tran TX. Clinical features and revised diagnostic criteria in Joubert syndrome. J Child Neurol 1999;14:583-90.  Back to cited text no. 3
Sghir M, Kesomtini W. A characteristic image in Joubert syndrome: Molar tooth sign. Pan Afr Med J 2015;21:69.  Back to cited text no. 4
Sturm V, Leiba H, Menke MN, Valente EM, Poretti A, Landau K, et al. Ophthalmological findings in Joubert syndrome. Eye (Lond) 2010;24:222-5.  Back to cited text no. 5
Joubert M, Eisenring JJ, Robb JP, Andermann F. Familial agenesis of the cerebellar vermis. A syndrome of episodic hyperpnea, abnormal eye movements, ataxia, and retardation. Neurology 1969;19:813-25.  Back to cited text no. 6
McGraw P. The molar tooth sign. Radiology 2003;229:671-2.  Back to cited text no. 7
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. 8
van Beek EJ, Majoie CB. Case 25: Joubert syndrome. Radiology 2000;216:379-82.  Back to cited text no. 9


  [Figure 1], [Figure 2], [Figure 3]


    Similar in PUBMED
   Search Pubmed for
   Search in Google Scholar for
 Related articles
    Access Statistics
    Email Alert *
    Add to My List *
* Registration required (free)  

  In this article
Clinical Image D...
Article Figures

 Article Access Statistics
    PDF Downloaded24    
    Comments [Add]    

Recommend this journal