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Imaging of Adult Ocular Abnormaliyes

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Imaging of Adult Ocular Abnormaliyes 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 Associaon of Radiologists mee1ng, 76th Annual Learning Objec1ves Review the anatomy of the globe Describe the features of traumac globe injuries. Describe the imaging features of non-traumac globe abnormali1es such as detachments and provide a differen1al for globe calcificaon. Provide an approach to evaluang ocular neoplasms. Review the common post-surgical changes of the globe. Anatomy 1 - Globe has 3 layers : Anterior Chamber 1. Fibrous coat Ciliary Cornea - formed by cornea anteriorly Body Lens and sclera posteriorly Vitreous Chamber 2. Uvea Re1na – formed by choroid, ciliary Sclera Choroid body and the iris 3. Re4na – neural layer, converts light Axial T1w, contrast enhanced into neural signals 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 Axial CT – contour abnormality - Collapsed globe (‘Flat 4re’ of globe with increased density sign) within posterior chamber in keeping with vitreous hemorrhage and globe rupture Globe Rupture - PiYalls Axial CT – scleral buckle Axial CT – contour and intra-ocular gas abnormality of the used in treatment of posterior globe in keeping re1nal detachment 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 2 chamber is sugges1ve Axial CT – subtle flaening and Axial CT – increased density volume loss of le[ anterior within anterior chamber making chamber compared to right – the lens look large in paent surgically proven corneal tear with clinical hyphema Lens Injuries3 - Include lens dislocaon and subluxaon - Can be traumac or non-traumac - If non-traumac, suggest work-up for connec1ve 1ssue disorders such as Marfan’s or Ehlers-Danlos syndrome Axial CT – 1lted appearance to Axial CT – lens dislocated and this dislocated lens. Note the sing within posterior chamber intra-ocular gas in keeping with globe rupture. Posterior Chamber Injuries - Vitreous hemorrhage is common - Re1nal detachment – assess for funnel shaped density or 6 signal along re1nal layer Serial CT’s in the same paent Axial CT – Increased density along imaged on Day 1, 4, and 12 posterior globe (arrows) is in keeping show progression of posterior with re1nal detachment. Loss of chamber hemorrhage globe volume and gas are in keeping with traumac globe rupture. Re1nal Detachment - Re1na is firmly aached at op1c nerve and oro-serrata (point at which choroid and ciliary body fibers converge) 6-7 - Fluid tracking between layers leads to ‘funnel’ shape density Axial CT – Increased funnel-shaped Axial T2w (le[) and T1w contrast density along posterior globe (arrows) is enhanced (right) images from in keeping with re1nal detachment. the same paent – arrows demonstrate a re1nal detachment. Choroidal Detachment - Fluid accumulates between choroid and sclera - Fluid tracks in a circumferen1al paern along the lateral 6 walls of the globe Axial CT – Increased density along Axial T2w (le[) and T1w (right) lateral globe (arrows) is in keeping images– arrows demonstrate with hemorrhagic choroidal choroidal detachment. detachment in this trauma paent. Globe Calcificaon - Wide differen1al that ranges from benign to malignant - Most common en11es include drusen, dystrophic calcificaon and phthisis bulbi Axial CT demonstrates an Axial CT demonstrates likely atrophic, collapsed, calcified dystrophic calcificaon of the globe in keeping with phthisis choroid in this paent who had bulbi. undergone previous radiaon for an op1c glioma. Globe Calcificaon Axial non-contrast CT demonstrates calcificaon at the op1c discs bilaterally in keeping with drusen. Axial contrast-enhanced CT demonstrates an enhancing mass within the le[ eye associated with calcificaon in this paent with primary breast cancer . Ophthalmi1s - Inflammaon of the globe can be due to extrinsic process such as orbital celluli1s7 - Can be due to primary intraocular inflammaon (endo-ophthalmi1s) from an infec1ous e1ology or from extrinsic delivery of infec1ous agents via surgery or trauma CT - stranding around globe with subtle CT – thickening of the globe with choroidal increased density along lateral margins detachment in this case of endo-ophthalmi1s (arrows) sugges1ve of choroidal detachment or effusion in this case of orbital celluli1s. Coat’s disease - Exudave 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 calcificaon in this 20 year old male with Coat’s disease. Ocular Neoplasms - O[en present with vision changes, but can be asymptomac - 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 Axial contrast-enhanced CT shows a mass within the le[ mass within the le[ eye associated with calcificaon in mandible that was at the inferior most aspect of the orbital exam this paent with primary breast cancer . in the same paent. Uveal Melanoma - Account for the majority of melanomas whose primary site is not the skin9 - Most commonly present in paents 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 aer 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- Axial CT demonstrates a normal ocular silicone implant used to bilateral post-cataract treat a re1nal detachment. appearance (arrow on le[) Post-surgical appearance - Varying procedures used to treat re1nal detachments Axial CT shows a scleral buckle Axial CT demonstrates a scleral around the right globe. buckle with air inside the globe. Post-surgical appearance - Prostheses can have varying appearances A B Axial CT demonstrates an A. Axial CT demonstrates a prosthesis within the le[ orbit ocular prosthesis within B. Sagi]al CT with bone algorithm demonstrates the same the right orbit. prosthesis. Summary - Traumac injuries to the globe include: globe rupture, anterior and posterior chamber hemorrhage, lens subluxaon/dislocaon, and detachments - Re1nal detachments have a funnel shape towards the opc disc while choroidal detachments are more lateral and circumferen4al - Globe calcificaon 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 traumac dislocaon 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-traumac orbital condi1ons: diagnosis with CT and MR imaging in the emergent seng. 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 correlaon: 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. .
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