POSTERIOR SEGMENT TRAUMA FOLLOWING AN IMPROVISED EXPLOSIVE DEVICE DETONATION
AMANDA S LEGGE, B.S.
ABSTRACT
CASE REPORT: A nineteen-year-old private first class was several feet away from an improvised explosive device (IED) upon
detonation. Consequentially his right optic nerve was severed by metal debris. Fundus exam showed an inferior retinal
detachment with multi-layered hemorrhages in that eye. Because that eye had no light perception, the patient is being
followed closely to detect signs of ocular discomfort, inflammation, traumatic glaucoma, or sympathetic ophthalmia of the
left eye.
DISCUSSION: Blast injuries, particularly from IEDs, are the most common injury in the Iraq and Afghanistan wars 1. Three
distinct types of blast injuries are recognized and each has the potential to cause devastating visual damage. Treatment
must be individualized for each IED blast patient initially. Long term sequelae, such as traumatic glaucoma and sympathetic
ophthalmia, must be considered. Rehabilitation is provided once eye health and prognosis has been assessed.
A significant percentage of military personnel
have sustained blast-induced injuries since the
start of the Iraq and Afghanistan wars2. Of
particular importance are traumatic brain
injuries and ocular injuries resulting from
improvised explosive devices (IEDs). IEDs are the
most common cause of blast exposures to our
current military personnel3. Therapeutic
measures vary by the nature and mechanism of
injury sustained, therefore each IED injury case is
unique and must be treated independently. The
following case report illustrates multiple ocular
injuries often encountered following an IED blast
and the individualized ocular treatment as
appropriate for this patient. Also included are
considerations for long term care related to the
eye and rehabilitation as needed.
CASE REPORT
HISTORY
The patient is a 19-year-old Hispanic male who is
a Private First Class soldier. He served in a U.S.
Army Infantry in Afghanistan until he sustained
multiple injuries from an IED. He reports that he
was walking a road in Afghanistan with other
soldiers when an IED detonated approximately
10 feet from them. He was apparently in the
front of the group and was propelled into a wall
subsequent to the blast.
He was medically evacuated to Germany and
presented there with multiple soft tissue
wounds, loss of vision in the right eye, and loss of
hearing from the right ear.
CT imaging revealed a 1.2 cm retro-orbital
metallic foreign body severing the right optic
nerve. The metal was not removed because of its
sensitive location.
He also suffered a right zygomatic arch fracture,
right tympanic membrane rupture, partial right
femoral nerve laceration with right lower
extremity weakness and a mild traumatic brain
injury. The patient denied loss of consciousness
at the time of the explosion and denied new or
unusual headaches since that time.
Prior to the blast, the patient’s medical and
ocular history was unremarkable.
dilated O.D., but anatomically normal, and
normal O.S.
The soldier presented to our office two months
after the blast injury. At that time he was
medicated with Oxycodone 5mg / APAP 325mg
as needed. He was using prednisolone acetate
1% four times a day and erythromycin ointment
four times a day in the right eye.
Hertel exophthalmometry with base 105 was
13mm O.D. and 11mm O.S.
The patient did not report any discomfort with
his eyes. He denied any visual or mobility issues
secondary to his monocular status. However he
did admit being slightly nervous while driving,
especially when merging into a new lane.
DIAGNOSTIC DATA
Upon our evaluation, 8 weeks after the blast, the
patient’s unaided visual acuity was no light
perception O.D. and 20/20 O.S. at distance and
near. The right pupil was fixed and dilated, the
left was normally reactive. Extraocular motility
testing found no restrictions of muscle
movement. Confrontation visual fields were full
to finger counting O.S.
Intraocular pressures were measured to be
13mm Hg O.D., O.S. Anterior segment evaluation
revealed a well-healed horizontal scar on the
upper and lower lids of the right eye with
resulting mild cicatricial ectropion of the lateral
lower lid. The left lids were normal. A resolving
subconjunctival
hemorrhage
was
noted
supratemporally in the right eye with minimal
injection inferiorly and associated mild diffuse
chemosis O.D. The left conjunctiva was white
and quiet. The corneal surface was smooth O.U.
The right anterior chamber had 3+ cells, most
were pigmented, and 1+ flare. The left anterior
chamber was deep and quiet. The iris was widely
Humphrey 30-2 visual field O.S. showed no signs
of visual pathway damage at or behind the
chiasm.
Gonioscopy revealed the most posterior
structure in all quadrants to be the ciliary body
face with minimal pigment O.U. There was no
sign of angle recession or microhyphema O.D.
Posterior segment examination of the right eye
revealed a dense, recent, vitreous hemorrhage
as well as a preretinal hemorrhage obscuring the
optic nerve. A significant, resolving, vitreous
hemorrhage was settled inferiorly near a
localized retinal detachment. Due to bleeding,
the extent of the detachment could not be
determined; however all other visible retina was
flat and attached. The left posterior segment
showed normal anatomy with a cup-to-disc ratio
of 0.6/0.55.
DIAGNOSIS AND MANAGEMENT
Surgical repair of the retina would be of no
benefit because of the optic nerve severance.
Although once the vitreal hemorrhages resolve,
the entire retina can be assessed and retinal
repair may be considered. The patient
understands this would not restore his vision.
The goal of the surgery would be to stabilize the
nerve lining. This would allow for the possibility
of a future intervention such as stem cell
regeneration to the optic nerve and therapeutics
that promote neural recovery5.
The patient was thoroughly educated of the
findings. Adaptation to his monocular status was
discussed. A motor vehicle education course was
offered to aid in monocular adaptation to
driving. This course would also suggest additional
mirror placement on the vehicle to aid in
awareness to his right periphery. He declined the
offer at this time.
He continued to use prednisolone acetate 1%
four times a day until the right intraocular
inflammation decreased. After 2 additional
weeks of treatment the steroid was
appropriately tapered.
An oculoplastics consultation was suggested for
the right lower lid ectropion. He declined at this
time. He continues with GenTeal gel drops at
night to protect the cornea from exposure
keratopathy.
Baring any change or setback, the patient will be
monitored at four month intervals for one year
to monitor for any signs of ocular discomfort,
increased inflammation, traumatic glaucoma of
the right eye, or sympathetic ophthalmia of the
left eye.
Protective eye wear and monocular safety was
discussed with the patient. A pair of
polycarbonate lenses was dispensed to be worn
on a daily basis. A pair of safety goggles and sun
lenses were dispensed to the patient for when
he returns to active duty in a few months.
DISCUSSION
IEDs are the most common cause of blast injury
in the Iraq and Afghanistan wars3. These are
typically fabricated from a 155-mm artillery shell
buried under asphalt. It is commonly triggered by
a cell phone from a remote location. The shell is
composed of improvised, easily obtainable,
shrapnel that may also be associated with
flammable
explosion1.
substances
to
enhance
the
Three distinct categories of blast injuries are
recognized based on mechanism of structural
damage. Primary blast injuries are caused by the
changes in atmospheric pressure from the blast
waves itself. Secondary wounds are related to
foreign bodies from the metal casing or other
materials projected from the IED. Tertiary
injuries are caused via the propulsion of the
victim from the blast into a stationary object and
result in a sudden, halting, impact4,5. This patient
presumably suffered all three types of blast
injuries, although there is arguable evidence that
primary blast injuries are sustained in survivors
of explosions6.
Each of these mechanisms of blast injury can
easily cause visual impairment. Percussive forces
can disrupt axons of the many nerves responsible
for clear and single vision. Penetrating injuries,
the majority of ocular injuries sustained in a
blast6, can be responsible for a multitude of ill
effects based on trajectory and endpoint.
Visual impairment resulting from blast injuries
can range from mild to severe. The most
common cause of severe vision loss is secondary
to optic nerve and retinal damage, or globe
rupture7. Other common causes of moderate to
severe visual impairment include diplopia,
corneal scar opacities, large hyphema, and vitreal
hemorrhage8,9.
Treatment must be individualized to each IED
blast patient based on the nature and
mechanism of each injury sustained. A
meticulous history must be obtained to elicit the
possible extent of all injuries. Careful inspection
of the eyes is necessary to rule out an intraocular
foreign body or globe rupture. Then injuries must
be documented in detail.
traumatized eye14 or any vision loss in the
subsequent eye13.
After any initial surgeries, final visual outcome
can be predicted in approximately four weeks.
An initially poor visual acuity does not guarantee
a similar end result5. In some cases, minimal
therapeutics and frequent monitoring is the
most appropriate treatment, as in this case.
Rehabilitative care is needed once eye health is
stabilized and prognosis is assessed. This must
also be individualized to the patient’s injuries
and concerns. Rehabilitation may include the use
of prism to neutralize diplopia or nystagmus,
visual spatial training, accommodative and/or
vergence facility training, ocular prosthetics,
mobility training, or driving education8.
Two long term considerations following ocular
injury from an IED blast include traumatic
glaucoma and sympathetic ophthalmia. Each can
present within a few days to many decades after
the initial injury10,11,12,13. Careful follow up and
patient education is required to detect these
issues early and prevent evisceration of the
IEDs can cause multiple and diverse injuries
throughout the body. Visual outcome greatly
varies by the type and extent of blast injury
sustained. Therefore it is important to consider
each case individually with regard to initial
treatment, long-term care, and rehabilitation.
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Hyer, R., Iraq and Afghanistan Producing New Pattern of Extremity War Injuries. Medscape Medical News, 2006. Accessed 4
January 2012: <http://www.medscape.com/viewarticle/528624>.
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Okie, S., Traumatic Brain Injury in the War Zone. N Engl J Med, 2005; 352: 2043-2047.
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