|Year : 2019 | Volume
| Issue : 1 | Page : 129-131
A case report of anterior visual pathway aplasia
Jakkidi Prathibha Reddy, Prabhu M Shanker, Geetha Ganesan, Rajesh Prabu
Department of Medical Retina, Sankara Eye Hospital, Coimbatore, Tamil Nadu, India
|Date of Submission||05-Mar-2018|
|Date of Acceptance||20-Aug-2018|
|Date of Web Publication||21-Dec-2018|
Dr. Jakkidi Prathibha Reddy
Sankara Eye Hospital, Sathy Road, Sivanandapuram, Coimbatore - 641 035, Tamil Nadu
Source of Support: None, Conflict of Interest: None
Keywords: Central nervous system malformations, no light perception, ocular malformations, Optic nerve aplasia
|How to cite this article:|
Reddy JP, Shanker PM, Ganesan G, Prabu R. A case report of anterior visual pathway aplasia. Indian J Ophthalmol 2019;67:129-31
|How to cite this URL:|
Reddy JP, Shanker PM, Ganesan G, Prabu R. A case report of anterior visual pathway aplasia. Indian J Ophthalmol [serial online] 2019 [cited 2019 Jun 18];67:129-31. Available from: http://www.ijo.in/text.asp?2019/67/1/129/248139
| Case Report|| |
A 6-year-old male child presented with no vision in both eyes, born to a nonconsanguineous marriage with uneventful perinatal period. Physical and general examination was normal. Ocular examination showed no light perception in both eyes. Anterior segment was within normal limits. Dilated fundus examination showed absence of optic disk and central retinal vessels [Figure 1]a and [Figure 1]b, [Figure 2]a and [Figure 2]b. B-scan echography showed normal globe on both sides and absence of optic nerve shadow. Flash visual evoked potential (VEP) showed no reproducible and consistent response suggesting absent response from both visual pathways. Magnetic resonance imaging (MRI) of the orbits and brain disclosed bilateral absence of the optic nerves, chiasm, and proximal part of optic tracts with no other significant abnormality in brain.
|Figure 1: (a) Fundus picture of RE showing no optic disk, choroidal tessellation is seen and (b) fundus picture of LE showing no optic disk, choroidal tessellation is seen|
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|Figure 2: (a) Right eye B-scan image showing normal globe with no optic nerve shadow and (b) left eye B-scan image showing normal globe with no optic nerve shadow|
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| Discussion|| |
Optic nerve aplasia (ONA) falls within a malformation complex which is fundamentally distinct from optic nerve hypoplasia, as evidenced by its tendency to occur unilaterally with frequent association of microphthalmos and other ocular malformations which are confined to the involved eye., Histopathological examination usually demonstrates a vestigial dural sheath entering the sclera in its normal position, as well as retinal dysplasia with rosette formation. Weiter et al. believed that the failure of the paraxial mesoderm to develop was probably not the cause of aplasia of the optic nerve because the dural sheath was present in the majority of their cases. Instead, they suggested that the ventral invagination of the optic vesicle causes nerve fiber misdirection and secondary atrophy. This was concurrent with Mann that failure of the fetal fissure to form causes misdirection of the nerve fibers [Figure 3] and [Figure 4]. This leads to their failure to reach the lateral geniculate body and their necrosis.
| Conclusion|| |
Bilateral optic nerve aplasia is rare, with most reported cases having ocular and major Central nervous system (CNS) malformations., Our case is peculiar as the child presented with bilateral aplasia of optic nerve, chiasm, and tracts with no other ocular anomalies and no neurological abnormalities.
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.
Financial support and sponsorship
Conflicts of interest
There are no conflicts of interest.
| References|| |
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Storm RL, PeBenito R. Bilateral optic nerve aplasia associated with hydranencephaly. Ann Ophthalmol 1984;16:988-92.
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[Figure 1], [Figure 2], [Figure 3], [Figure 4]