Doctor's Information

Name : Morteza
Family :Sanei Taheri
Email : This email address is being protected from spambots. You need JavaScript enabled to view it.
Resident : Samira Shahhamzei

Patient's Information

Gender : Male
Age : 52

Case Section

Head & Neck Imaging

Clinical Summary

A 52 y/o man with visual loss

Images

Imaging Procedures and Findings

Coronal and sagittal T1-weighted (picture 1,2) and coronal and axial T2-weighted images (picture 3,4) show a lesion in the posterior of right globe with high signal in T1WI and decreased signal in T2WI suggestive melanin content of tumor . Left vitreous cavity shows hyposignal in T1 and T2 due to degenerative changes.

Discussion

Primary orbital melanoma usually presents as an ocular lesion. It originates in the uveal tract (iris, choroid, and ciliary bodies) and may extend posteriorly to the rest of the orbit. On MRl studies, the amount of melanin contained in melanoma determines the signal characteristics. Melanin shortens T1 and T2, thereby causing increased signal on Tl-weighted images and mildly decreased signal on T2-weighted images. The presence of gadolinium enhancement favors melanomas and helps differentiate the tumor from retinal detachment. Nonpigmented melanomas cannot be reliably differentiated from other masses.

Final Diagnosis

Uveal melanoma

References

Hagga John R. CT and MRI of the Whole body , 5th edition. P486-487

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