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764
Injuries of the Globe: What Can
the Radiologist Offer?1
Edward K. Sung, MD
Rohini N. Nadgir, MD
Akifumi Fujita, MD2
Cory Siegel, MD
Roya H. Ghafouri, MD
Anastasia Traband, MD
Osamu Sakai, MD, PhD
RadioGraphics 2014; 34:764–776
Published online 10.1148/rg.343135120
Content Codes:
From the Departments of Radiology (E.K.S.,
R.N.N., A.F., C.S., O.S.), Ophthalmology
(R.H.G., A.T.), and Otolaryngology–Head and
Neck Surgery (O.S.), Boston Medical Center,
Boston University School of Medicine, 820 Harrison Ave, FGH Building, 3rd Floor, Boston, MA
02118; and the Department of Radiology (A.F.),
Jichi Medical University School of Medicine,
Shimotsuke, Tochigi, Japan. Presented as an education exhibit at the 2012 RSNA Annual Meeting. Received June 3, 2013; revision requested
July 11 and received August 19; accepted August
29. For this journal-based SA-CME activity, the
author O.S. has disclosed financial relationships;
the other authors, editor, and reviewers have no
relevant relationships to disclose. Address correspondence to E.K.S. (e-mail: edward.sung@
bmc.org).
1
Current address: Department of Radiology, Boston Medical Center, Boston University
School of Medicine, Boston, MA.
2
SA-CME LEARNING OBJECTIVES
After completing this journal-based SACME activity, participants will be able to:
■■Describe normal ocular anatomy at CT
and MR imaging.
■■List
the advantages and disadvantages
of various imaging modalities for evaluating globe injuries.
■■Discuss
the various types of traumatic
injuries of the globe and their potential
mimics at CT and MR imaging.
See www.rsna.org/education/search/RG.
An earlier version of this article
was published in print and contains an error in Figure 1.
Traumatic ocular injuries are a significant cause of blindness and
visual deficits. In the setting of acute orbital trauma, urgent ophthalmologic evaluation and intervention are critical in preserving
vision. However, in the acute trauma setting, clinical evaluation of
the globe may be difficult in the presence of surrounding periorbital
soft-tissue swelling and other associated injuries, and patient cooperation may be limited because of unresponsiveness, altered mentation, or sedation. Often, rapid access to imaging is part of the initial
diagnostic evaluation, and radiologists may be the first to identify
traumatic injuries of the globe. Because of this, radiologists should
be familiar with normal orbital and globe anatomy at various imaging modalities and have a thorough understanding of the various
patterns of ocular injury and their imaging appearances. Radiologists should also be familiar with the various mimics of ocular injury, including congenital and acquired conditions that may alter
the shape of the globe, various types of ocular calcifications, and the
different types of material used to treat retinal detachment. Such
knowledge may help radiologists make accurate diagnoses, which
facilitates prompt and appropriate patient care.
©
RSNA, 2014 • radiographics.rsna.org
Introduction
Eye injuries account for approximately 3% of all emergency room
visits in the United States (1,2). The World Health Organization estimates that eye injuries result in blindness in about 1.6 million people
and unilateral blindness or decreased vision in almost 19 million
people each year (3). Thus, it is apparent that eye injuries are a significant cause of disability, especially in young men, in whom ocular
trauma is predominant (3–6).
The overall prevalence of trauma-related eye injuries is approximately 2%–6%, with as many as 97% of cases resulting from blunt
trauma (7,8). Common mechanisms of injury include motor vehicle
accidents, sports-related accidents, industrial accidents, falls, and violent trauma (1,2,7–9). Patients with trauma-related facial fractures
are at an increased risk for associated eye injuries, and the incidence
of vision loss and blindness related to facial fractures may be as high
as 10.8% (7,9–12). Ocular involvement may also be seen in as many
as 84% of patients with head injuries (13). For this reason, the presence of facial fractures or head injuries should prompt a thorough
assessment for potential ocular injury.
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Figure 1. Diagram shows normal ocular
anatomy. AC = anterior chamber, C = cornea,
CB = ciliary body, Ch = choroid, I = iris, L =
lens, ON = optic nerve, PS = posterior segment (vitreous body), R = retina, Sc = sclera.
Figure 2. Normal orbital anatomy. Axial unenhanced CT (a) and T1-weighted MR (b) images show
normal orbital anatomy. AC = anterior chamber, C = cornea, CB = ciliary body, Ch = choroid, L = lens,
LR = lateral rectus muscle, MR = medial rectus muscle, ON = optic nerve, PS = posterior segment (vitreous body), R = retina, Sc = sclera.
Urgent ophthalmologic evaluation is important for prompt and appropriate management
of ocular injuries (10,11). However, because of
surrounding periorbital soft-tissue swelling and
other associated injuries, physical examination of
the globe may be difficult in the setting of acute
trauma, and patient cooperation may be limited
by unresponsiveness, altered mentation, or sedation. In the presence of such factors, imaging is
necessary to assess the extent of injuries. Radiologists may be the first to identify any injuries of
the globe; thus, knowledge of the various ocular
injuries and their imaging appearances is crucial
in making accurate diagnoses to guide proper
patient treatment. In this article, we discuss the
normal ocular anatomy, the various patterns of
ocular injury and their imaging appearances, and
potential mimics of injury.
Normal Anatomy
Understanding the normal anatomy and terminology of the globe is crucial to accurately identify and describe globe injuries (Fig 1). The globe
consists of three layers: the sclera and cornea,
which make up the protective outer layer of the
globe and maintain its shape and pressure; the
retina, which makes up the sensory inner layer;
and the uveal tract, which makes up the middle
vascular layer and contains the choroid, ciliary
body, and iris (14). Often, the various layers of
the globe are difficult to distinguish at imaging,
especially computed tomography (CT) (Fig 2a).
However, the sclera may be distinguished from
the choroid at high-resolution magnetic resonance (MR) imaging (Fig 2b).
The globe is also divided into anterior and posterior segments by the lens. The anterior segment
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contains aqueous humor and is further divided
into anterior and posterior chambers, which are
separated by the iris. The posterior chamber is
often small and difficult to visualize at imaging.
The posterior segment is posterior to the lens and
contains vitreous humor. It is also known as the
vitreous body.
Imaging Modalities
CT is the modality of choice for the initial evaluation of a traumatic injury to the globe, especially
when intraorbital or intraocular foreign bodies
are suspected (1,2,15–20). Access to CT scanners is widely available, and images may be rapidly acquired during evaluation of head injuries.
CT also has excellent resolution of bones and
soft tissue and easily depicts most foreign bodies.
However, the presence of metallic foreign bodies or medical devices may cause streak artifact,
which may obscure some findings. The main disadvantage of CT is its use of ionizing radiation.
The increasing role of CT in medical imaging,
especially in the acute trauma setting, has led to
increased exposure to ionizing radiation. Therefore, every attempt to minimize radiation dose
while maintaining image quality should be made,
including modifying the scanning mode, voltage,
current, exposure time, pitch, section thickness,
and reconstruction algorithms (21). At our institution, orbital CT images are acquired helically
from the frontal to the maxillary sinuses with the
following parameters: 120 kVp, 100 mAs, 1.25mm section thickness with 1.25-mm intervals,
and a pitch of 0.969. Images are reconstructed in
soft tissue and bone kernels in both axial and coronal planes. Iterative reconstruction techniques
are applied for further dose reduction, with resulting CT dose index values of 20 mGy or less.
CT protocols vary among institutions, and optimal imaging parameters should be established by
a joint effort among radiologists, technologists,
and physicists.
Ultrasonography (US) may also be performed
to evaluate for globe injuries and may depict
various ocular injuries, including hyphema, lens
dislocations, globe rupture, intraocular foreign
bodies, and vitreous and retinal hemorrhage
(18,22,23). US is easily accessible and does not
expose patients to ionizing radiation. However,
the image quality is operator dependent, and
US is considered contraindicated in those with
suspected globe rupture (1,2,16,18,20,22,23). In
addition, US is less sensitive than CT for depicting intraocular foreign bodies (18–20,22).
Magnetic resonance (MR) imaging offers superior definition of orbital soft-tissue without the
use of ionizing radiation (1,16). However, it may
not be widely accessible, may be time-consum-
Figure 3. Corneal laceration in a 12-year-old boy.
Photograph shows a full-thickness corneal laceration
with iris prolapse (arrow).
ing, has poor definition of bone structures, and
is contraindicated in those with metallic foreign
bodies (1,2,15,16,18,20). Therefore, MR imaging is usually reserved for patients with suspected
ocular injuries that are not readily apparent at
CT, such as subtle open-globe injuries or organic
foreign bodies (17,18,24–26).
Conventional radiography may be used to
evaluate for orbital fractures or radiopaque foreign bodies in the setting of a traumatic injury
(1,2,27). However, its sensitivity for depicting
fractures or foreign bodies is far less than that of
CT, and it provides limited information on orbital soft tissues (1,2,27).
Anterior Chamber Injuries
Anterior chamber injures are often difficult to diagnose radiologically, and are usually more readily identified at clinical examination. Common
injuries involving the anterior chamber include
corneal lacerations and hyphema.
Corneal Laceration
Lacerations of the cornea are usually associated
with penetrating trauma. The severity of the
injury may vary, from superficial to deeper penetrating injuries. Superficial injuries are usually
not apparent at imaging, but they may be readily
identified at clinical examination (Fig 3). Corneal lacerations with complete penetration of the
cornea may lead to globe rupture, which may be
seen at CT as decreased volume of the anterior
chamber (2,15,28).
Hyphema
Hyphema is defined as a collection of blood
in the anterior chamber of the globe that usually results from disruption of the blood vessels
in the iris or ciliary body (1,2,15). Usually, it
is readily apparent at clinical examination as a
blood-fluid level (Fig 4). At unenhanced CT, it
may be seen as an area of hyperattenuation in
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Figure 4. Hyphema in a 26-year-old man. Photograph
shows a blood-fluid level in the anterior chamber (arrow), a finding consistent with hyphema.
Figure 5. Partial lens dislocation in a 70-year-old man.
Axial unenhanced CT image shows a normally positioned left lens with an abnormal orientation (arrow), a
finding consistent with partial lens dislocation. The left
lens has relatively decreased attenuation compared with
the normal right lens, a finding indicative of traumatic
cataract. In addition, an area of hyperattenuation is seen
in the anterior chamber (arrowhead), a finding consistent with hyphema.
the anterior chamber (Fig 5) (1,2). Hyphema
may also be readily identified at US; however,
placing excessive pressure on the globe is not
recommended in patients with hyphema (22).
The presence of hyphema should prompt a
search for other globe injuries.
Lens Injuries
The lens is surrounded by a capsule and suspended by radially oriented zonular fibers that
are connected to the ciliary body. Blunt force that
is applied to the globe in the anterior-posterior
direction redistributes in the equatorial direction,
which may cause the attachments of the zonular
fibers on the lens to stretch and possibly tear.
This mechanism can result in partial or complete
dislocation of the lens (1,2,15).
Partial Lens Dislocation
A tear involving only one side of the zonular
fibers leads to partial dislocation of the lens, in
Figure 6. Posterior complete lens dislocation
in a 72-year-old man. Axial unenhanced CT (a)
and T2-weighted MR (b) images show the left
lens, which is completely dislocated and dependently layered in the posterior segment of the left
globe (arrow).
which the lens is freely mobile on the side of the
torn attachments but is still fixed on the side of
the intact attachments, causing the lens to be oriented in an abnormal direction, usually with the
torn segment dependently displaced. Displacement of the lens is readily identified at imaging
(Fig 5) (1,2,15,22).
Complete Lens Dislocation
A tear involving all of the zonular fibers around
the lens causes complete dislocation of the lens,
which usually dislocates into the posterior segment and may be dependently layered in the
posterior aspect of the globe at imaging (Fig 6)
(1,2,15,22). Lens dislocation into the anterior
segment is much less common because anterior
movement of the lens is restricted by the iris
(Fig 7) (15).
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Non-Traumatic Dislocation
In the absence of trauma, lens dislocation may occur in patients with certain connective tissue disorders, such as Marfan syndrome, Ehlers-Danlos
syndrome, and homocystinuria. In these cases, the
dislocation is often bilateral (2). Patient history is
important in distinguishing between traumatic and
nontraumatic lens dislocation that is related to an
underlying disorder.
Traumatic Cataract
Blunt trauma to the globe may also disrupt the
lens capsule, which may lead to edema within the
lens, which, in turn, may lead to the development
of a cataract. Cataracts are readily identifiable at
clinical examination (Fig 8). At CT, the affected
edematous lens may appear relatively hypoattenuating compared with the nonaffected lens (Fig 5)
(1). A mature cataract may be hyperattenuating
or even calcified (29).
Figure 7. Anterior complete lens dislocation in a 56year-old man. Axial unenhanced CT image shows anterior dislocation of the lens in the left globe (arrow).
Posterior Segment Injuries
The wall of the posterior segment of the globe is
composed of three layers: the sclera, the outermost layer; the retina, the innermost layer; and
the choroid, the middle vascular layer. Trauma to
the globe may disrupt the attachments between
these layers and result in detachments.
Figure 8. Traumatic cataract in a 54-year-old man.
Photograph shows a cataract (arrow) that was caused
by an old traumatic injury.
Retinal Detachment
The retina, the innermost layer of the globe, is
firmly attached to the ora serrata anteriorly and
the optic disc posteriorly. A traumatic tear in
the retina allows vitreous fluid and blood to collect between the retina and choroid, resulting in
detachment of the retinal layer. Because of the
firm retinal attachments at the optic disc, retinal
detachments may have a characteristic V-shaped
appearance at imaging, with the apex at the optic
disc (Figs 9, 10) (1,2,22).
Choroidal Detachment
The choroid is a vascular layer located between
the retina and sclera. When a traumatic injury
results in decreased ocular pressure, the pressure
within the suprachoroidal space also decreases,
which allows fluid or blood to accumulate and
results in detachment of the choroidal layer. Usually, choroidal detachments have a lentiform or
biconvex shape at imaging and spare the posterior portion of the globe (Fig 11) (1,2,22).
Vitreous Hemorrhage
Trauma to the globe may disrupt retinal blood
vessels and result in hemorrhage in the vitreous humor of the posterior segment. Vitreous
hemorrhage is readily seen at CT as hyperattenuating fluid in the posterior segment (Fig 12)
(1,2). It may also be seen at US; however, severe
vitreous hemorrhage may obscure other ocular
findings (22).
Open-Globe Injuries
Open-globe injuries, also known as globe rupture, are a major cause of blindness (1–3,28).
Blunt trauma to the globe can disrupt the integrity of the sclera and result in globe rupture.
Scleral tears from blunt trauma typically occur
behind the insertions of the extraocular muscles,
where the sclera is thinnest (1,2). Penetrating
injuries may also disrupt the sclera and, when
they are deep enough, lead to globe rupture.
Open-globe injuries related to blunt trauma are
more frequently seen in women, whereas those
related to penetrating trauma are more frequently seen in men (3).
CT is the initial imaging modality of choice
in the setting of ocular trauma with a suspected
open-globe injury (2,15,26,28). Its sensitivity
for depicting an open-globe injury is approximately 56%–75% when the injury is clinically
suspected and 56%–68% when it is clinically
occult (2,15,28). MR imaging may provide
more detailed information about the globe and
should be considered when a clinically suspected open-globe injury is not identified at CT.
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Figures 9, 10. (9) Retinal detachment in a 69-yearold woman. US image shows a complex fluid collection (arrow) in the posterior aspect of the globe.
(10) Retinal detachment in an 82-year-old man.
Axial unenhanced CT (a) and fluid-attenuated
inversion-recovery (FLAIR) MR (b) images show a
V-shaped fluid collection (arrows) in the posterior
segment of the right globe, with the apex at the optic
disc. The fluid collection is hyperattenuating at CT
and hyperintense at FLAIR MR imaging, a finding
consistent with hemorrhage. Note that the right lens
was replaced.
Figure 11. Choroidal detachment in a 75-yearold woman. Axial unenhanced CT image shows
hyperattenuating fluid along the lateral and medial
margins of the posterior segment of the right globe
(arrows) with sparing of the most posterior portion
of the globe. Note that the right lens was replaced.
Figure 12. Vitreous hemorrhage in a 92-yearold woman. Axial unenhanced CT image shows
near-homogeneous hyperattenuation in the
posterior segment of the right globe (arrow), a
finding consistent with vitreous hemorrhage, and
periorbital soft-tissue swelling (arrowheads).
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Figure 13. Open-globe injury in a 68-year-old woman. Axial (a) and coronal (b) unenhanced CT images show an
abnormal contour of the left globe (arrows), a finding consistent with globe rupture.
Figure 14. Open-globe injury in a 48-year-old man. (a) Axial unenhanced CT image shows slight flattening of the
posterior aspect of the right globe (arrow) and adjacent vitreous hemorrhage. (b) Coronal unenhanced CT image
shows a more obvious contour abnormality of the right globe (arrowhead), a finding consistent with globe rupture.
Figure 15. Open-globe injury resulting from a gunshot wound in a 20-year-old man. Photograph (a) and axial unenhanced CT image (b) show complete rupture of the left globe (arrow in b). Metallic bullet fragments are seen in
the left periorbital soft tissues (arrowhead in b).
In general, US is considered to be contraindicated when an open-globe injury is suspected
(1,2).
Direct Signs of Open-Globe Injury
Direct imaging findings of open-globe injuries
include alteration of the globe contour or volume and evidence of scleral discontinuity (Fig 13)
(1,2,15,28). These findings may range in conspicuity from obvious to very subtle, and evaluation of
the globe in multiple planes may be useful (Fig 14).
Obvious cases are often related to severe trauma,
such as a gunshot wound (Fig 15). When a clinically suspected open-globe injury is not readily
identified at CT, MR imaging has been shown to
have increased sensitivity in depicting subtle areas of scleral discontinuity (26).
Indirect Signs of Open-Globe Injury
One indirect imaging finding of open-globe injuries is alteration of the anterior chamber depth.
Anterior chamber depth may increase when
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Figure 16. Open-globe injury in a 44-yearold man. Axial unenhanced CT image shows
that the depth of the anterior chamber of
the left globe (arrow) is slightly increased
compared with the right side. Punctate areas
of hyperattenuation are seen in the posterior
segment (arrowhead), a finding consistent
with vitreous hemorrhage.
Figure 17. Open-globe injury in a 30-year-old man with an intraocular foreign body. Axial unenhanced
CT images obtained at the level of the lens (a) and more superiorly (b) show a metallic foreign body
(arrow in a) and air (arrowheads in b) in the posterior segment of the right globe. The shape of the right
globe is relatively preserved.
the sclera in the setting of a traumatic injury
(Fig 17) (1,2,15,28).
Mimics of Open-Globe Injury
Figure 18. Coloboma in a 35-year-old man. Axial
unenhanced CT image shows that the posterior aspect
of the right globe has an abnormal contour (arrow), a
finding consistent with coloboma.
a rupture is present in the posterior segment,
which decreases pressure and volume and allows
the lens to sink posteriorly (Fig 16) (1,2,15,28).
Conversely, decreased anterior chamber depth
may result from a severe corneal laceration,
which leads to decreased volume in the anterior
segment (2,15,28). Another indirect finding
of open-globe injuries is an intraocular foreign
body or air, which implies penetration through
Radiologists should be familiar with nontraumatic mimics of open-globe injuries, which include congenital and acquired deformities of the
globe such as coloboma, staphyloma, congenital
glaucoma, an elongated globe from myopia, and
phthisis bulbi (Figs 18–20) (1,2,15). Mass effect
from an orbital mass or hematoma may also alter
the globe contour (2,15). In addition, radiologists
should not mistake ocular calcifications or the
material used to treat retinal detachment as an
intraocular foreign body.
Intraocular Foreign Bodies
In the United States, an average of 3.1 penetrating eye injuries occur per 100,000 person-years
(6). Common mechanisms of injury include violent trauma, motor vehicle accidents, recreational
accidents, and work-related industrial accidents
(6). Intraorbital foreign bodies are present in
approximately 10%–17% of all ocular injuries,
and intraocular foreign bodies may be present in
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Figures 19, 20. (19) Myopia-related globe elongation in a 71-year-old man. Axial unenhanced CT image shows
that both globes have an elongated contour (arrow). (20) Phthisis bulbi in a 75-year-old woman. Axial unenhanced
CT image shows that the right globe is shrunken and calcified (arrow), a finding consistent with phthisis bulbi and
the result of an old injury.
Figures 21, 22. (21) Intraocular foreign body
in a 48-year-old man. Axial unenhanced CT image shows a metallic foreign body in the anterior
chamber of the left globe (arrow). (22) Intraocular foreign body in a 56-year-old man with nailgun injuries. Frontal radiograph (a) and axial
unenhanced CT image (b) show a nail in the
scalp and another extending into the right globe
(arrow in b).
as many as 41% of open-globe injuries (20,30).
Identification of intraocular foreign bodies is
important because they may lead to infection,
retinal toxicity, or vision loss if not appropriately
treated. The location of an intraocular foreign
body may vary, but they are most commonly seen
in the posterior segment (20).
CT is the imaging modality of choice when
intraorbital or intraocular foreign bodies are suspected (1,2,17–20,22,25,30). Its sensitivity for
depicting foreign bodies varies widely depending
on the type and size of foreign bodies present,
but it may be as high as 100% (20). MR imaging
is contraindicated in the presence of a metallic
foreign body but is more sensitive than CT in
depicting organic material (17,18,25). US may
also depict intraocular foreign bodies, but it is
less sensitive than CT, and intraocular air may
mimic a foreign body (22). The rate of conventional radiography for depicting intraorbital and
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Figure 23. Intraorbital plastic foreign body in
a 48-year-old man. Coronal (a) and sagittal (b)
unenhanced CT images show a plastic chopstick in the right orbit (arrows) and extending
intracranially through the orbital apex.
Figure 24. Intraorbital wooden foreign bodies in
an 82-year-old woman. Axial unenhanced CT image
shows linear hypoattenuating foreign bodies in the
left orbit (arrows), a finding consistent with a known
penetrating trauma from wooden foreign bodies.
intraocular foreign bodies ranges from 40% to
90% and depends on the type of material present (20,27). In general, the sensitivity of radiographs for depicting intraocular foreign bodies
is lower than that of CT; however, it may be as
high as 96% when there is clinical evidence of a
penetrating ocular injury (27). Still, radiographs
play a limited role in the setting of acute trauma
because they provide little information about the
orbital soft tissues.
Types of Foreign Bodies
Intraorbital foreign bodies may be inorganic
or organic. Inorganic foreign bodies are more
frequently encountered and most commonly include metal and glass (17,19,20,30,31). Usually,
they are associated with vision loss and, because
they are inert, do not elicit an inflammatory response (17). Metal is readily identified at CT
(Figs 17b, 21, 22). However, because glass may
vary in composition, its attenuation at CT also
varies (18). CT is still considered the imaging
modality of choice and has been shown to depict
as many as 96% of glass foreign bodies that are at
least 1.5 mm and as many as 48% of glass foreign
bodies that are 0.5 mm (18). Another type of
inorganic foreign body that may be encountered
is plastic, which is hyperattenuating—but not as
hyperattenuating as metal—at CT (Fig 23).
The most commonly encountered organic
foreign body is wood (17). Organic foreign bodies may elicit a marked inflammatory response
and may cause a severe infection (17,25,30,31).
If they are initially undiagnosed, chronic or recurrent orbital infections may result (30). Detecting wood at CT may be difficult because
it appears hypoattenuating in the acute phase,
an appearance that mimics that of air (Fig 24)
(1,2,17,24,25,30). Typically, wood has a geometric shape, a feature that may help distinguish
it from air (1). In addition, its attenuation may
change over time, from isoattenuating relative to
orbital soft tissue in the subacute phase to hyperattenuating in the chronic phase (25,30). When a
wooden foreign body is clinically suspected and
not apparent at initial CT, MR imaging may depict inflammation, which is commonly associated
with organic foreign bodies (1,17,18,24,25).
Mimics of Intraocular Foreign Bodies
Radiologists should be familiar with different patterns of ocular calcifications, as well as the appearance of the various materials used to treat retinal
detachment to avoid misdiagnosing a foreign body
or other orbital injury. Calcifications that occur
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Figure 25. Optic drusen in a 42-year-old
woman. Axial unenhanced CT image shows a
punctate calcification near the optic disc in the
right globe (arrow), a finding consistent with an
optic drusen.
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Figure 26. Scleral plaques in a 90-year-old
woman. Axial unenhanced CT image shows
scleral calcifications at the insertion sites of the
medial and lateral rectus muscles (arrows), a finding consistent with scleral plaques.
Figure 27. Scleral band in a 40-year-old man. Axial (a) and coronal (b) unenhanced CT images show
a hyperattenuating band (arrows) around the right globe, a finding consistent with a scleral band.
near the optic disc are referred to as optic drusen
and are associated with macular degeneration (Fig
25). They may be a cause of benign pseudopapilledema (32). Calcifications that occur along the
insertions of the medial and lateral rectus muscles
are known as scleral plaques and are commonly
seen in elderly patients (Fig 26) (32). The lens
may also be calcified from a cataract. These ocular
calcifications should not be mistaken for intraocular foreign bodies. Common materials used
to treat retinal detachment include scleral bands,
silicon oil, and gas (Figs 27–30) (2,32).
Blast Injuries
Radiologists should also be aware of the potential
for ocular involvement in blast injuries. Although
explosions are rare in industrial and recreational
accidents, the increasing rate of terrorist- and
combat-related explosions have increased the
likelihood that health-care providers will encounter these injuries (33–35). Injuries from a blast
may be primary or secondary. Primary blast injuries result from the high-pressure blast waves
generated from an explosion, which cause direct
tissue damage (35). Secondary blast injuries result from debris that is physically displaced by the
blast wave (35).
Ocular injuries may occur in 10%–28% of
blast injuries (34,35). Among blast survivors,
most ocular injuries result from penetrating or
blunt trauma from debris from a blast wave (a
secondary blast injury) (34,35). The patterns
of ocular blast injuries vary; the most common
injuries include corneal lacerations, open-globe
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Figure 28. Intraocular silicon oil in a 79-year-old man.
Axial unenhanced CT image shows hyperattenuating
material (arrow) in the posterior segment of the left
globe, a finding consistent with silicon oil.
Figure 29. Intraocular silicon oil in a 79-year-old man. Axial T1-weighted (a) and T2-weighted (b) MR images
show material in the posterior segment of the right globe (arrow) that is isointense at T1-weighted imaging and hypointense at T2-weighted imaging, a finding consistent with silicon oil.
Figure 30. Intraocular gas from pneumatic
retinopexy in a 44-year-old woman. Axial unenhanced CT image shows hypoattenuating
gas with attenuation similar to that of air layering in the nondependent portion of the posterior segment of the left globe (arrow), a finding
consistent with prior pneumatic retinopexy.
cal evaluation may be challenging in the acute
trauma setting. Often, CT is the initial imaging
modality of choice in the setting of traumatic
facial injuries, and radiologists may be the first
to diagnose ocular injuries. Familiarity with the
various types of ocular injuries and their imaging
appearances, as well those of potential mimics of
injury, are crucial in making accurate diagnoses
that will appropriately guide patient care.
injuries, intraocular foreign bodies, and vitreous
hemorrhage (33–35). Radiologists should thoroughly evaluate the globes for any type of injury
in patients who sustained a blast.
Conclusions
Ocular injuries are fairly common and are a significant cause of blindness and vision deficits.
Urgent ophthalmologic evaluation is critical to
prevent permanent visual deficits, but physi-
Disclosures of Conflicts of Interest.—O.S.: Related
financial activities: receives royalties from McGraw-Hill
and honoraria for lectures from Bracco Diagnostics,
Inc, and Kyorin USA, Inc. Other financial activities:
none.
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TM
This journal-based SA-CME activity has been approved for AMA PRA Category 1 Credit . See www.rsna.org/education/search/RG.
Teaching Points
May-June Issue 2014
Injuries of the Globe: What Can the Radiologist Offer?
Edward K. Sung, MD • Rohini N. Nadgir, MD • Akifumi Fujita, MD • Cory Siegel, MD • Roya H. Ghafouri,
MD • Anastasia Traband, MD • Osamu Sakai, MD, PhD
RadioGraphics 2014; 34:764–776 • Published online 10.1148/rg.343135120 • Content Codes:
Page 768
Because of the firm retinal attachments at the optic disc, retinal detachments may have a characteristic
V-shaped appearance at imaging, with the apex at the optic disc (Figs 9, 10) (1,2,22).
Page 768
Usually, choroidal detachments have a lentiform or biconvex shape at imaging and spare the posterior
portion of the globe (Fig 11) (1,2,22).
Page 770
One indirect imaging finding of open-globe injuries is alteration of the anterior chamber depth.
Page 771
Radiologists should be familiar with nontraumatic mimics of open-globe injuries, which include congenital and acquired deformities of the globe such as coloboma, staphyloma, congenital glaucoma, an elongated globe from myopia, and phthisis bulbi (Figs 18–20) (1,2,15). Mass effect from an orbital mass or
hematoma may also alter the globe contour (2,15).
Page 773
Detecting wood at CT may be difficult because it appears hypoattenuating in the acute phase, an appearance that mimics that of air (Fig 24) (1,2,17,24,25,30).