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Head trauma with contralateral traumatic optic neuropathy
Brijesh Takkar, Digvijay Singh, Rohit Saxena, Vimla Menon
Department of Ophthalmology, Dr. Rajendra Prasad Centre for Ophthalmic Sciences, AIIMS, New Delhi, India
Introduction
There was also an extension of the fracture line with involvement
of the left foramen ovale and foramen spinosum.
Indirect traumatic optic neuropathy occurs in closed head trauma
with a reported incidence varying from 0.5 to 5%. The neuropathy
is typically seen on the same side as the blunt trauma.[1] We present
a case of traumatic optic neuropathy involving the contralateral
orbit, with a continuous fracture line running from the side that
sustained the trauma to the opposite optic canal.
Considering the late presentation at our center, no further
treatment was offered to the patient.[2,3] At the follow‑up after
a month, the patient started developing disc pallor and after a
Comment
A 20‑year‑old male presented with loss of vision in the left eye
seven days after sustaining trauma, to the right forehead, in a road
traffic accident (RTA). The patient displayed no signs of any brain
injury. On external examination, an abrasion on the right forehead
and a right facial palsy, possibly due to direct impact to the right
preauricular region, were seen [Figure 1a]. Ocular examination
revealed visual acuity of 6/5 in the right eye and no perception of
light in the left eye. Subconjunctival hemorrhage in the right eye
and an afferent pupillary defect (APD) in the left eye were noted
with the absence of any signs of intraocular trauma. The extraocular
movements of both the eyes and the Goldman visual field of the
right eye were within normal limits [Figure 1b]. There was no sign
of trauma to the midfacial region or the left side of the face.
Figure 1a: Right‑sided forehead abrasion and facial palsy along with subconjunctival
hemorrhage; left eye is diverging
Noncontrast computed tomography (NCCT) using a
high‑resolution algorithm in coronal and sagittal reconstructions
revealed a continuous fracture line running obliquely from the right
to the left side involving the superomedial margin of the right orbit,
along the floor of the anterior cranial fossa to involve the left optic
canal with a mildly thickened optic nerve [Figure 2]. Fracture of the
left optic canal had no bony spicule protruding into it. There was a
mild thickening of the intraorbital part of the left optic nerve. Both
globes, extraocular muscles, and right optic nerve were normal.
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DOI:
10.4103/0974-620X.111925
Figure 1b: Normal Goldman visual field of the right eye
Copyright:  2013 Takkar B, et al. This is an open‑access article distributed under the terms of the Creative Commons Attribution License, which
permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.
Correspondence:
Dr. Brijesh Takkar, Fellow, Vitreo‑Retina Services, Dr. R.P. Centre, AIIMS, New Delhi - 110 029, India. E‑mail: [email protected]
Oman Journal of Ophthalmology, Vol. 6, No. 1, 2013
61
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Takkar, et al.: Unusual case of traumatic optic neuropathy
Figure 2a: Axial noncontrast computed tomography (NCCT) scan in bone window
showing the fracture line (white arrow heads) extending from the right superomedial
orbital margin (white arrow) to the left optic canal (black arrow)
Figure 2b: Coronal noncontrast computed tomography (NCCT) scan showing
thickening of the left optic nerve (white arrow)
Figure 2c: Coronal noncontrast computed tomography (NCCT) scan in bone window
showing fracture of the superior margin of the left optic canal (white arrow) with
associated mucosal thickening of the sphenoid sinus (black arrow); also seen is the
fracture of the lateral wall of left pterygoid bone (white arrow head)
Figure 2d: 3d Reconstruction noncontrast computed tomography (NCCT) scan shows
the fracture line running obliquely (white arrow heads) from right to left along the
floor of the cranial fossa to involve the left optic canal (white arrow) and also the left
foramens of ovale and spinosum (black arrow)
period of three months, he had total optic atrophy and continued
to have no light perception vision in the left eye.
in one eye following trauma to the opposite side of the head and
also highlights the requirement of a detailed examination of both
eyes in all cases of trauma.
The human orbit has multiple weak areas vulnerable to fracture.
Fractures of such ‘eggshell areas’ of anterior cranial fossa maybe
produced by trivial injuries[4] as in our case. Conventionally, head
trauma results in ipsilateral indirect traumatic optic neuropathy
due to the unique arrangement and shape of the orbital bones.
Holographic interferometric analysis of the human skull
demonstrates that structural strain induced by frontal loading
results in deformation of the ipsilateral orbital roof near the optic
foramen.[5] Right orbital trauma is indicated by the presence of
subconjunctival hemorrhage, facial palsy, and forehead abrasion
on the right side The presence of a fracture line involving the
right orbital margins and the right anterior cranial fossa confirm
this. Unexpectedly, this fracture line continued to run through
the opposite optic canal resulting in left optic neuropathy, sparing
the right optic nerve, with the result that the patient maintained
normal visual acuity and a normal visual field in the right eye.
This case illustrates the possibility of traumatic optic neuropathy
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References
1.
2.
3.
4.
5.
Das H, Badhu BP, Gautam MA. Indirect traumatic optic neuropathyretrospective interventional case series from a tertiary care center in
eastern Nepal. JNMA J Nepal Med Assoc 2007;166:57‑61.
Steinsapir KD, Goldberg RA. Traumatic optic neuropathy: An evolving
understanding. Am J Ophthalmol 2011;6:928‑33.
Volpe NJ, Levin LA. How should patients with indirect traumatic optic
neuropathy be treated?. J Neuroophthalmol 2011;2:169‑74.
Hirsch CS, Kaufman B. Contrecoup skull fractures. J Neurosurg 1975;5:530‑4.
Gross CE, DeKock JR, Panje WR, Hershkowitz N, Newman J. Evidence
for orbital deformation that may contribute to monocular blindness
following minor frontal head trauma. J Neurosurg 1981;6:963‑6.
Cite this article as: Takkar B, Singh D, Saxena R, Menon V. Head trauma
with contralateral traumatic optic neuropathy. Oman J Ophthalmol 2013;6:61-2.
Source of Support: Nil, Conflict of Interest: None declared.
Oman Journal of Ophthalmology, Vol. 6, No. 1, 2013