EE024 Imaging of the Globe - CAR Lifelong Learning...Anatomy’ J 1Globe’has’3’layers :...
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Imaging of adult ocular abnormali1es. Sangha B, Agovida B, Forster BB, and Andrews G University of Bri1sh Columbia, Department of Radiology Vancouver, Bri1sh Columbia, Canada Canadian Associa1on of Radiologists mee1ng, 76 th Annual
Transcript of EE024 Imaging of the Globe - CAR Lifelong Learning...Anatomy’ J 1Globe’has’3’layers :...
Imaging of adult ocular abnormali1es.
Sangha B, Agovida B, Forster BB, and Andrews G
University of Bri1sh Columbia, Department of Radiology Vancouver, Bri1sh Columbia, Canada
Canadian Associa1on of Radiologists mee1ng, 76th Annual
Learning Objec1ves Review the anatomy of the globe
Describe the features of trauma1c globe injuries.
Describe the imaging features of non-‐trauma1c globe abnormali1es such as detachments and provide a
differen1al for globe calcifica1on.
Provide an approach to evalua1ng ocular neoplasms.
Review the common post-‐surgical changes of the globe.
Anatomy -‐ Globe has 3 layers1:
1. Fibrous coat -‐ formed by cornea anteriorly
and sclera posteriorly
2. Uvea – formed by choroid, ciliary
body and the iris
3. Re4na – neural layer, converts light
into neural signals
Sclera Choroid
Re1na
Vitreous Chamber
Lens
Anterior Chamber
Cornea
Re1na
Ciliary Body
Axial T1w, contrast enhanced fat saturated image
Globe Rupture – Findings2-‐5
-‐ Loss of volume or contour abnormality
-‐ Discon4nuity of the fibrous coat (sclera or cornea)
-‐ Intra-‐ocular foreign body -‐ Intra-‐ocular gas
-‐ Collapsed globe (‘Flat 4re’ sign)
Axial CT – contour abnormality of globe with increased density within posterior chamber in
keeping with vitreous hemorrhage and globe rupture
Globe Rupture -‐ PiYalls
Axial CT – scleral buckle and intra-‐ocular gas used in treatment of re1nal detachment
Axial CT – contour abnormality of the
posterior globe in keeping with a staphyloma
Anterior Chamber Injuries -‐ Hyphema or hemorrhage in anterior chamber is o[en
clinically evident (assess for increased density) -‐ Imaged to rule-‐out corneal rupture or other injuries
-‐ Corneal tear or rupture – decreased volume of anterior chamber is sugges1ve2
Axial CT – subtle fla]ening and volume loss of le[ anterior chamber compared to right – surgically proven corneal tear
Axial CT – increased density within anterior chamber making the lens look large in pa1ent
with clinical hyphema
Lens Injuries3 -‐ Include lens disloca1on and subluxa1on -‐ Can be trauma1c or non-‐trauma1c
-‐ If non-‐trauma1c, suggest work-‐up for connec1ve 1ssue disorders such as Marfan’s or Ehlers-‐Danlos syndrome
Axial CT – 1lted appearance to this dislocated lens. Note the intra-‐ocular gas in keeping with
globe rupture.
Axial CT – lens dislocated and sibng within posterior chamber
Posterior Chamber Injuries -‐ Vitreous hemorrhage is common
-‐ Re1nal detachment – assess for funnel shaped density or signal along re1nal layer6
Serial CT’s in the same pa1ent imaged on Day 1, 4, and 12
show progression of posterior chamber hemorrhage
Axial CT – Increased density along posterior globe (arrows) is in keeping with re1nal detachment. Loss of
globe volume and gas are in keeping with trauma1c globe rupture.
Re1nal Detachment -‐ Re1na is firmly a]ached at op1c nerve and oro-‐serrata (point at
which choroid and ciliary body fibers converge) -‐ Fluid tracking between layers leads to ‘funnel’ shape density6-‐7
Axial T2w (le[) and T1w contrast enhanced (right) images from the same pa1ent – arrows demonstrate a re1nal
detachment.
Axial CT – Increased funnel-‐shaped density along posterior globe (arrows) is in keeping with re1nal detachment.
Choroidal Detachment -‐ Fluid accumulates between choroid and sclera
-‐ Fluid tracks in a circumferen1al pa]ern along the lateral walls of the globe6
Axial T2w (le[) and T1w (right) images– arrows demonstrate
choroidal detachment.
Axial CT – Increased density along lateral globe (arrows) is in keeping
with hemorrhagic choroidal detachment in this trauma pa1ent.
Globe Calcifica1on -‐ Wide differen1al that ranges from benign to malignant
-‐ Most common en11es include drusen, dystrophic calcifica1on and phthisis bulbi
Axial CT demonstrates an atrophic, collapsed, calcified globe in keeping with phthisis
bulbi.
Axial CT demonstrates likely dystrophic calcifica1on of the choroid in this pa1ent who had undergone previous radia1on
for an op1c glioma.
Globe Calcifica1on
Axial contrast-‐enhanced CT demonstrates an enhancing mass within the le[ eye
associated with calcifica1on in this pa1ent with primary breast
cancer .
Axial non-‐contrast CT demonstrates calcifica1on at the op1c discs bilaterally in keeping
with drusen.
Ophthalmi1s -‐ Inflamma1on of the globe can be due to extrinsic process such as
orbital celluli1s7 -‐ Can be due to primary intraocular inflamma1on (endo-‐ophthalmi1s)
from an infec1ous e1ology or from extrinsic delivery of infec1ous agents via surgery or trauma
CT -‐ stranding around globe with subtle increased density along lateral margins
(arrows) sugges1ve of choroidal detachment or effusion in this case of orbital celluli1s.
CT – thickening of the globe with choroidal detachment in this case of endo-‐ophthalmi1s
Coat’s disease -‐ Exuda1ve re1ni1s
-‐ Predominantly occurs in young males around age 10, but can present in adult males8
Axial CT shows increased density of exudate between layers of re1na (arrow) with
associated calcifica1on in this 20 year old male with Coat’s disease.
Ocular Neoplasms
-‐ O[en present with vision changes, but can be asymptoma1c
-‐ Metastases are most common malignant neoplasm presen1ng within the globe in adults
-‐ Uveal melanoma is most common primary malignant neoplasm in adults
-‐ Intraocular schwannoma is a benign neoplasm which can mimic an uveal melanoma
Metastases -‐ Breast and lung cancers tend to be most frequent primary
site of metastases presen1ng within the globe -‐ Look for addi1onal lesions on rest of images
Axial contrast-‐enhanced CT demonstrates an enhancing mass within the le[ eye
associated with calcifica1on in this pa1ent with primary breast
cancer .
Axial contrast-‐enhanced CT shows a mass within the le[
mandible that was at the inferior most aspect of the orbital exam
in the same pa1ent.
Uveal Melanoma -‐ Account for the majority of melanomas whose primary site
is not the skin9 -‐ Most commonly present in pa1ents in their 50’s
Axial T2w, axial T1w and axial T1w contrast-‐enhanced images – demonstrate a low T2 signal, high T1 signal, enhancing mass in
posterior chamber that was pathologically an uveal melanoma with re1nal detachment.
Intra-‐ocular Schwannoma -‐ Mimic uveal melanomas on imaging
-‐ Tend to be located in cilio-‐choroidal region10 -‐ O[en diagnosed on pathology a[er surgical removal
Axial T1w, fat-‐saturated, Axial T2w and Axial T1 contrast-‐enhanced images – demonstrate a high T1
signal, low T2 signal, enhancing mass in the region of the ciliary body that was pathologically a schwannoma.
Post-‐surgical appearance -‐ Post surgical appearances are commonly mistaken for
pathology11
Axial CT demonstrates intra-‐ocular silicone implant used to treat a re1nal detachment.
Axial CT demonstrates a normal bilateral post-‐cataract
appearance (arrow on le[)
Post-‐surgical appearance -‐ Varying procedures used to treat re1nal detachments
Axial CT shows a scleral buckle around the right globe.
Axial CT demonstrates a scleral buckle with air inside the globe.
Post-‐surgical appearance -‐ Prostheses can have varying appearances
A. Axial CT demonstrates a prosthesis within the le[ orbit B. Sagi]al CT with bone algorithm demonstrates the same
prosthesis.
A B
Axial CT demonstrates an ocular prosthesis within
the right orbit.
Summary -‐ Trauma1c injuries to the globe include: globe rupture,
anterior and posterior chamber hemorrhage, lens subluxa1on/disloca1on, and detachments
-‐ Re1nal detachments have a funnel shape towards the op1c disc while choroidal detachments are more lateral
and circumferen4al -‐ Globe calcifica1on can be of benign or malignant e1ology.
-‐ Most common malignant globe masses in adults are metastases and uveal melanoma.
-‐ Post-‐surgical changes of the globe can have varying appearance.
Thanks References: 1. Mafee MF, Karimi A, Shah J et al. Anatomy and pathology of the eye: role of MR imaging and CT. Neuroimaging Clin N Am 2005; 15: 23-‐47. 2. NovellineRA, Liebig T, Jordan et al. Computed tomography of ocular trauma. Emerg Radiol 1994; 1: 56–67 3. JosephDP, Pieramici DJ, Beauchamp NJ. Computed tomography in the diagnosis and prognosis of open globe injuries. Ophthalmology 2000; 107:1899–1906 4. Hardjasudarma M, Rivera E, Ganley JP, McClellan RL. Computed tomography of trauma1c disloca1on of the lens. Emerg Radiol 1994; 1: 180–182 5. Kubal W. Imaging of orbital trauma. Radiographics 2008; 28: 1729-‐39. 6. Mafee MF, Peyman G. Re1nal and choroidal detachments: role of magne1c resonance imaging and computed tomography. Radiol Clin North Am 1987. 25:487-‐507. 7. Lebedis CA, Osamu S. Non-‐trauma1c orbital condi1ons: diagnosis with CT and MR imaging in the emergent sebng. Radiographics 2008; 28: 1741-‐53. 8. Kadom N, Sze RW. Radiologic reasoning: leukocoria in a child. Am J Roentgenol 2008; 191: 40-‐44. 9. Houle V, Belair M, Allaire GS. AIRP best cases in radiologic-‐pathologic correla1on: choroidal melanoma. Radiographics 2011; 31:1231-‐36. 10. Xian J, Xu X, Wang Z et al. MR imaging findings of the uveal schwannoma. AJNR 2009; 30: 7669-‐773. 11. Hunter TB, Yoshino MT, Dzioba RB et al. Medical devises of the head, neck, and spine. Radiographics 2004; 24:257-‐285.
