Lymphoid Tumors of the Lacrimal Gland

Lymphoid tumors of the lacrimal gland range from pseudotumors to reactive lymphoid hyperplasia to malignant lymphomas of various types. They tend to involve the orbital and palpebral lobes of the lacrimal gland, resulting in anterior and posterior extension. Lymphoid tumors share similar acoustic characteris-tics.35 Topographically, there is diffuse enlargement of the lacrimal gland with quite regular internal structure and low reflectivity on A scan. Sound attenuation is minimal.

FIGURE 8.13. Lacrimal gland lesions. (A) Pleomorphic adenoma. A-scan echogram displays a regular internal structure with high reflectivity that relates histologically to the multiple contiguous tubular structures embedded in the dense connective tissue.33 L, lesion. Sound attenuation is moderate (angle k = 45°). These acoustic characteristics of pleomorphic adenomas are similar to those seen in cavernous hemangiomas. Since most cavernous hemangiomas occur within the muscle cone, the location and the clinical presentation of the tumor clearly are important diagnostic clues.5'34 (B)

FIGURE 8.13. Lacrimal gland lesions. (A) Pleomorphic adenoma. A-scan echogram displays a regular internal structure with high reflectivity that relates histologically to the multiple contiguous tubular structures embedded in the dense connective tissue.33 L, lesion. Sound attenuation is moderate (angle k = 45°). These acoustic characteristics of pleomorphic adenomas are similar to those seen in cavernous hemangiomas. Since most cavernous hemangiomas occur within the muscle cone, the location and the clinical presentation of the tumor clearly are important diagnostic clues.5'34 (B)

Carcinoma of the lacrimal gland. In the early development of these tumors, the echographic finding shows a V-shaped pattern on A scan, where the anterior and posterior parts of the lacrimal gland retain the normal high-reflective character while the central portion representing the carcinoma site is less reflective because of the condensed cellularity; hence the V-shaped pattern (arrow). With an increase in the size of the tumor, the central portion of the V area becomes less reflective. (C) Dacryoadenitis. B-scan echogram shows an enlarged lacrimal gland (L) with moderate echolucency.

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