How would a sonographer identify a choroidal melanoma on ultrasound?

A choroidal melanoma can be effectively identified on ultrasound primarily through its echogenicity, size, and shape. This type of intraocular tumor presents with specific ultrasound characteristics that differentiate it from other lesions.

In terms of echogenicity, choroidal melanoma typically appears as a medium to high echogenic mass. The size of the lesion is significant, as choroidal melanomas can grow to a considerable diameter, usually more than 5 mm in height or width. The shape is also important; these tumors often have a dome-shaped appearance, which can help in distinguishing them from other types of lesions, such as retinal detachments or hemangiomas that may have different echogenic features and contours.

In contrast, while the location of the tumor in the eye can provide additional information, it is not a definitive method for identification solely based on standard ultrasound imaging. Colors are not discerned through ultrasound imaging in the same way as optical techniques; therefore, color is not a reliable characteristic. Patient symptoms can guide the diagnostic process but are subjective and not directly visualized through ultrasound. Thus, echogenicity, size, and shape remain the most crucial factors in accurately identifying choroidal melanoma via ultrasound.