IMAGES IN NEUROLOGY
|Year : 2021 | Volume
| Issue : 4 | Page : 590-591
Transmantle heterotopia or closed lip schizencehaly: A diagnostic dilemma
Nishant Nayyar, Dinesh Sood, Preeti T Kapila, Narvir S Chauhan, Varsha Patial
Department of Radio-Diagnosis, Dr RPGMC, Tanda, Himachal Pradesh, India
|Date of Submission||19-Jan-2021|
|Date of Acceptance||26-Feb-2021|
|Date of Web Publication||21-May-2021|
Senior Resident, Department of Radiodiagnosis, Dr RPGMC, Tanda - 176 001, Himachal Pradesh
Source of Support: None, Conflict of Interest: None
|How to cite this article:|
Nayyar N, Sood D, Kapila PT, Chauhan NS, Patial V. Transmantle heterotopia or closed lip schizencehaly: A diagnostic dilemma. Ann Indian Acad Neurol 2021;24:590-1
|How to cite this URL:|
Nayyar N, Sood D, Kapila PT, Chauhan NS, Patial V. Transmantle heterotopia or closed lip schizencehaly: A diagnostic dilemma. Ann Indian Acad Neurol [serial online] 2021 [cited 2021 Oct 25];24:590-1. Available from: https://www.annalsofian.org/text.asp?2021/24/4/590/316502
| Case History|| |
A 41-year-old adult male presented with two episodes of generalized tonic clonic seizures. He had past history of seizures from childhood with seizure-free intervals, and the last episode was about 2 years back. The patient was taking phenytoin off and on for last 10 years which was prescribed by a local practitioner. On physical examination, the patient was afebrile, disoriented, and showing gum hypertrophy. The neurological examination suggested dysarthria, nystagmus, and positive cerebellar signs. The patient had not been evaluated with any previous imaging for the epilepsy. Magnetic resonance imaging (MRI) was done with 1.5 Tesla GE machine. On MRI, T1- and T2-weighted sagittal images showed continuous altered signal intensity areas at two sites in the right frontal lobe extending from the ventricular wall to the cortex [Figure 1]a & [Figure 1]b. The altered signal intensity areas were iso-intense to gray matter on all pulse sequences without obvious intervening cerebrospinal fluid (CSF) cleft. They were seen continuous with overlying gray matter of the cortex and causing bulge on the lateral ventricular wall. The left cerebral hemisphere showed multiple foci of similar signal intensity in the subcortical region of the frontal lobe on T1- and T2-weighted images [Figure 1]c and [Figure 1]d. In addition to the above imaging findings, there was diffuse bilateral cerebellar and vermian atrophy with prominent posterior fossa extra-axial spaces [Figure 1]e & [Figure 1]f. The bilateral cerebellar atrophy was developed as consequences of long-term phenytoin use explaining positive neurological examination.
|Figure 1: Magnetic resonance imaging (MRI) T1- (a) and T2- (b) weighted sagittal images showing continuous layer of gray matter in the right frontal lobe (arrows) at two sites extending from ventricular wall to cortex and causing bulge on the ventricular wall without intervening CSF cleft suggesting transmantle heterotopia (typical imaging features to differentiate from closed lip schizencephaly). T1- (c) and T2- (d) weighted axial MRI images showing multiple foci of gray matter in the left frontal lobe (arrows) suggesting subcortical heterotopia. T2-weighted coronal (e) and axial (f) MRI images showing bilateral cerebellar and vermian atrophy|
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| Discussion|| |
The continuous layer of gray matter extending from the ventricle to cortex is seen in transmantle heterotopia and closed lip schizencephaly, both of which are difficult to differentiate on imaging. Transmantle heterotopia is a rare entity in which gray matter is seen extending from the ventricular wall to overlying cortex without intervening white matter or CSF cleft.,,,, Schizencephaly refers to gray matter lined cleft extending from the ventricular wall to cortex and can be open or closed lip type. In open lip, the cleft walls are well separated and filled with CSF, whereas they are in apposition in closed type., The differentiating feature between closed lip schizencephaly and tranmantle heterotopia is the CSF cleft which is sometimes difficult to discern. In our opinion, the best differentiating feature between these two conditions is “dimple sign” which is always seen in closed lip schizencephaly. In closed lip schizencephaly, a dimple is seen on the ventricular outline where gray matter meets the ventricular wall while heterotopic gray matter bulges into the wall. In our case, the absence of CSF cleft and dimple sign with gray matter bulging on the ventricular wall suggested transmantle heterotopia in the right cerebral hemisphere with focal subcortical heterotopia in the contralateral hemisphere.
Declaration of patient consent
The authors certify that they have obtained all appropriate patient consent forms. In the form the patient(s) has/have given his/her/their consent for his/her/their images and other clinical information to be reported in the journal. The patients understand that their names and initials will not be published and due efforts will be made to conceal their identity, but anonymity cannot be guaranteed.
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Conflicts of interest
There are no conflicts of interest.
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