The Journal of the Arkansas Medical Society Issue 4 Volume 115 | Page 20

CASE STUDY
Traumatic Extradural Internal Carotid Artery Pseudoaneurysm
Resulting in Insidious Onset Carotid Cavernous Fistula
Lindsay Mohney, DO; 1 Sarah Hunton, MD; 1, Rani Lindberg, MD; 2
1
Resident Physician, Department of Physical Medicine and Rehabilitation, UAMS
2
Associate Professor, Department of Physical Medicine and Rehabilitation, UAMS
Abstract
arotid cavernous fistula (CCF) is
a condition resulting from abnor-
mal cavernous sinus and carotid
artery communication from a ruptured
infraclinoid aneurysm. Traumatic aneurysms
C
represent 0.15-0.4% of intracranial aneurysms,
usually affecting young males, and are vulnerable
to fractures due to typically anterior locations. In
this case, a 59-year-old woman with traumatic
brain injury had initial imaging revealing skull
fractures, hemorrhages, and 3.5mm right inter-
nal carotid artery pseudoaneurysm. Three weeks
later, exam revealed right ocular bruit. CTA head
confirmed CCF. Acute injuries can mask symptoms
of CCF and delay diagnosis. Early intervention of
asymptomatic aneurysms may reduce or eliminate
risk of CCF.
3mm right pupil and sluggish 2mm left pupil, loss
of right corneal reflex, and progressive midline shift
on repeat CT head. Pre-operative CT Angiogram
revealed 3.5mm probable pseudoaneurysm involv-
ing the right internal carotid artery in the lacerum
segment just inferior to the cavernous segment;
due to emergent issues requiring craniectomy,
pseudoaneurysm was not addressed during acute
management.
Post operatively, patient had left periorbital
ecchymosis, right ptosis, and right-sided facial
and periorbital swelling, but pupils were reactive
bilaterally. Right corneal edema was noted post op
day four, and lubrication was ordered for her eyes.
Patient was transferred to long-term acute care,
and ophthalmology was consulted to evaluate
right-eye redness and swelling that began post-
operatively. PM&R was consulted 16 days after
injury; on exam, patient was able to open eyes on
command, but was noted to have mild right-eye
proptosis and conjunctival injection. Ophthalmol-
ogy assessment also noted similar ocular exam
findings and unremarkable bedside internal ocu-
lar exam without a clear cause for symptoms. On
follow-up PM&R exam (21 days post-injury), pa-
tient was unable to open right-eye. Exam revealed
worsening right-eye proptosis and conjunctival
injection. An ocular bruit was noted with right-eye
Case Diagnosis
A 59-year-old traumatic brain injury patient
with acute traumatic extradural pseudoaneurysm
that resulted in a CCF complicating her post-op-
erative course.
Case Description
A 59-year-old woman was admitted to the
hospital after an unhelmeted motorcycle accident
that resulted in traumatic brain injury, GCS 8. Initial
CT imaging showed: non-depressed right parietal
and temporal skull fractures, right mastoid frac-
ture extending to the temporal squamous bone
with pneumocephalus, bi-frontal and right tem-
poroparietal intraparenchymal and subarachnoid
hemorrhages, 5mm right-to-left midline shift, and
small bi-frontal and right frontotemporal subdu-
ral hemorrhages. Patient underwent a large right
decompressive hemi-craniectomy approximately
eight hours after admission due to persistently el-
evated, acute onset of anisocoria with nonreactive
Figure 1: CT angiogram of the head demonstrating right internal CCF with marked
exophthalmos and dilated orbital veins.
92 • THE JOURNAL OF THE ARKANSAS MEDICAL SOCIETY
VOLUME 115