DIFFERENTIAL DIAGNOSIS OF PIGMENTED CHOROIDAL LESIONS

Introduction. Pigmented lesions of the choroidal layer of the eye are challenging to diagnose, yet proper identification is critical due to the potential life-threatening risk of malignant melanoma. Lesions that appear benign may in fact be primary or secondary malignancies, while lesions that initially appear ominous are benign. This poster will present two different cases of pigmented posterior segment lesions along with a strategy for differential diagnosis, management, and follow up. Case presentation. Case 1 is a 65 YO WM with a 25 year history of heavy smoking presenting for routine care. A raised suspicious lesion was detected in the posterior pole of one eye. The lesion was evaluated by a retinologist and was diagnosed as a choroidal nevus. The patient was remanded to yearly follow up. Case 2: A 61 YO HF presented for routine care with complaints of blurry vision in both eyes, with a past history of laser vision corrective surgery in one eye. Examination of the fundus showed a pigmented lesion involving 60% of the posterior segment in the left eye, and a similar but smaller lesion in the right eye. Ultrasonography revealed that both lesions were moderately elevated with high acoustical signaling. An Optical Coherence Tomography (OCT) analysis showed unusual contouring of the posterior segment in the left eye, with moderate thickening of the peri-macular space in the right eye. The patient was referred for a retina consult, but due to financial constraints the appointment was not immediately scheduled. Deviation From the Expected. Case 2 presents with very large basal diameter lesions in the absence of visual symptoms. Typical growth would involve not only the basal dimension but also a dramatic increase in apical height. Case 1 presented with an expected basal and apical size relationship, yet the lesion was deemed to be benign. Discussion. Analysis of pigmented posterior segment lesions should include an evaluation of size, height, presence or absence of drusen, lipofuscin, subretinal fluid, and associated disruptions to adjacent tissues\u27 structure and function. Ancillary testing may include OCT, ultrasonography, visual field analysis, fluorescein angiography, photography, and possibly CT and/or MRI in certain cases. A discussion of prevalence of malignant lesions is included, along with a review of the Collaborative Ocular Melanoma Study (COMS). Conclusion. A careful approach to diagnosis of pigmented posterior segment lesions is essential for proper management and follow up. Improperly managed malignant melanoma can results in catastrophic vision loss, loss of independence, and death. Grants. N/