Transcript The *Guitar Pick* Sign: An expanding repertoire of

The “Guitar Pick” Sign:
An expanding repertoire of
orbital pathology
Vincent Dam MD, Joel Stein MD, PhD, Suyash Mohan MD
Department of Radiology
Perelman School of Medicine at the University of Pennsylvania
Control #: 1751, Poster #: EE-12
Disclosures
• Vincent Dam, MD: No disclosures
• Joel Stein, MD, PhD: No disclosures
• Suyash Mohan, MD: No disclosures
Purpose
• Posterior globe tenting, the “guitar pick” sign,
has been associated with acute and often
permanent visual impairment.
• The finding is usually seen in the context of
orbital trauma and other acute inflammatory
pathologies.
Guitar pick
Axial image of an orbital CT in a patient with ocular trauma and left retrobulbar
hemorrhage (not shown) with posterior tenting of the left globe.
Purpose
• Few cases to date have been reported in
association with progressive infiltrating
neoplasm.
• Our case serves to expand the clinical context in
which the “guitar pick” sign can be seen.
Case Report
• A 61-year-old man with locally advanced
sinonasal adenoid cystic carcinoma and
resultant left eye blindness presented to
outpatient clinic with acute right eye blindness
of 12 hours duration.
• The patient was transferred to the emergency
department where an unenhanced maxillofacial
CT was obtained followed by an MRI.
11/2014
b
a
Axial (a) & coronal (b)
maxillofacial CT
demonstrate extensive
infiltrating neoplasm
involving the sinonasal
cavity with bilateral
intraorbital extension
(yellow arrows) and
resultant bilateral "guitar
pick" signs (red arrows).
9/2014
c
d
Comparison to prior
sinus CT from 9/2014,
axial and coronal planes
(c & d), demonstrates
11/2014 findings are
new and likely
correspond to acute
symptomatology.
11/2014
MRI orbits: Axial & coronal post contrast T1 weighted images corroborate CT
findings with extensive infiltrating neoplasm involving the sinonasal cavity with
bilateral intraorbital extension (yellow arrows).
Notice, “guitar pick” signs are manifested in the bilateral globes, more
conspicuous on the left (red arrows).
Treatment & Follow-up
• Based on the imaging findings, the patient was
admitted and given a course of high dose
corticosteroids as well as targeted radiation.
Right eye vision returned after treatment.
• MRI of the orbits 1 month later demonstrated
improved left and resolution of right posterior
orbital tenting.
12/2014
a
b
Follow up axial (a) &
coronal (b) post
contrast T1 weighted
MRI shows marked
decrease in tumor
extent with
corresponding
resolution of bilateral
posterior globe
tenting.
11/2014
This is compared to
the MRI obtained at
the time of the
patient’s acute
presentation (c & d).
c
d
Summary
 In addition to prior reports, the guitar pick sign can be
seen with infiltrative neoplasms on both CT and MR
imaging modalities and corresponds to acute visual
impairment.
 Prompt medical intervention is essential and can prevent
permanent visual damage.
References
• Dalley RW, Robertson WD, Rootman J. Globe tenting: a sign
of increased orbital tension. AJNR Am J Neuroradiol
1989:10(1):181-6.
• Hrach CJ, Quint DJ. Globe tenting as a result of head
trauma. AJNR Am J Neuroradiol 1997:18(5):980-2.
• Theoret J, Sanz GE, Matero D, et al. The “guitar pick” sign: a
novel sign of retrobulbar hemorrhage. CJEM Can J Emerg
Med Care 2011:13(3):162-4.