Expert Witness Journal Issue 64 December 2025 - Flipbook - Page 78
Indirect Optic Nerve Trauma
Resulting In Visual Field Loss
by Nicholas A Jacobs
acuity was not a昀昀ected. This 昀椀eld loss means that
she has di昀케culty noticing people and objects on her
right.
Introduction
Classical teaching holds that a traumatic optic nerve
injury will result in a major loss of visual acuity and
pallor of the optic disc a few weeks later. [Ref. 1]
Investigation showed a normal appearing optic disc
(Fig 1a) a normal OCT scan of the nerve 昀椀bre layer
thickness (Fig 1b) and a visual 昀椀eld loss of the Right
eye (Fig 1c)
I present a series of thirteen patients who su昀昀ered
indirect optic nerve injury. That is to say a blow to
the head (10 cases) or to the eyeball itself (3 cases)
without anatomical disruption of the optic nerve.
The salient feature of these cases is that they all
have a degree of visual 昀椀eld loss, but they all have
completely normal appearing optic discs. The other
test which is carried out on patients, apart from
examination of the optic nerve and assessment of
the visual 昀椀eld test is the OCT scan of the retina
and retinal nerve 昀椀bre layer. Optical Coherence
Tomography is a painless imaging test that uses
light waves to create detailed cross-sectional 3 D
images of the retina and its layers. In this series 6
out of the 13 had OCT scans, which were not helpful
in predicting the visual 昀椀eld losses in these cases.
The message of this review is that even in relatively
minor head injuries, not necessarily resulting in
loss of consciousness, a visual 昀椀eld test is mandatory.
This also applies to a direct eyeball blunt injury
where a visual 昀椀eld test is feasible.
Fig. 1a
Case Presentations
I now present three (part-昀椀ctitious) cases.
As well as the visual 昀椀eld loss, symptoms such
as photophobia and 昀椀ndings such as PTSD-like
symptoms were common.
Patient A - Miss A had a road tra昀케c accident (car
v lorry). She sustained a blow to the right side of
the head and lost consciousness. She noticed some
loss of vision immediately after the accident. On
testing 30% of the 昀椀eld of vision of the Right eye was
missing on the outer side. Fortunately, the visual
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Fig. 1b
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DECEMBER/JANUARY 2025-2026
