Clinical Features

Clinically, orbital lymphangioma usually presents with a slowly progressive proptosis, globe displace-

ment, ptosis, and eye motility restriction (Figures 14.8 and 14.9).37 The eyelids may have a bluish discoloration due to subcutaneous involvement of the lym-phangioma (Figure 14.8). The conjunctiva may show clear or hemorrhagic lymph channels (Figure 14.8).38 Rarely, a focal lesion may remain asymptomatic.

Spontaneous hemorrhage is the most dreaded occurrence in a lymphangioma and may lead to eyelid ecchymosis, subconjunctival hemorrhage, and acute proptosis (Figure 14.6). This may create diagnostic difficulty in a patient with a previously undiagnosed asymptomatic lymphangioma. Acute increase in intraorbital pressure can result in compressive optic neuropathy and vision loss.37,39 In the clinical differential diagnosis of spontaneous orbital hemorrhage, the following possibilities should be considered in addition to lymphangioma: trauma, bleeding disorder, orbital varix, and, rarely, cavernous hemangioma. One characteristic feature of lymphangioma is that the proptosis is exacerbated after trauma or upper respiratory tract infection.38,40 Under these circumstances, hemorrhage into the channels of the tumor may lead to the development of chocolate cysts.

Orbital lymphangioma may occupy an intraconal or extraconal (Figures 14.9 and 14.10) location.41 Differential diagnosis of this tumor should include cavernous hemangioma, hemangiopericytoma, fibrous histiocytoma, or neurilemoma and solitary neural tumors.

Orbital lymphangioma can rarely be associated with an orbital and/or intracranial arteriovenous malformation.42,43 Another rare complication of orbital

FIGURE 14.8. (A) Facial and (B) slit lamp photographs show swelling of the right periorbital tissues in a 4-year-old girl with right orbital lymphangiomas; note lateral displacement and clear conjunctival lymph channels on the medial conjunctiva. (C) Photograph of the open mouth showing a similar lesion affecting the soft palate. (D) T2-weighted axial MR image demonstrating various lymphatic cysts hyperintense to the extraocular muscle and cerebral gray matter in the right orbit. The cysts contain higher and lower intensity fluid, demonstrating a fluid-fluid level. The higher intensity fluid is due to the release of methemoglobin into the superior portion of the cyst. Histopathologic examination reveals large bloodless ectatic lymph channels lined by thinned endothelial cells. There are lymph follicles within the connective tissue trabeculae. The lymphangioma channels may appear empty, if intralesional hemorrhage has occurred; however, they will contain blood. Inset: Gross photograph of the partially excised lymphangioma. (F) Postoperative facial appearance showing complete resolution of right proptosis and eyelid swelling after partial excision of the lesion.

lymphangioma is association with orbital cellulitis. Because of its infiltrating nature, orbital lymphan-gioma may provide a route of entry for infections into the orbit from otherwise minor infections of the periocular skin and eyelids.44

Patients with orbital lymphangioma can have similar lesions in the skin and mucous membranes of the head including the soft palate (Figure 14.8). It is important to examine the skin and soft palate of the patient with orbital lymphangioma.38

FIGURE 14.9. (A) Lymphangioma in a 24-year-old woman causing marked axial proptosis due to multicystic tumor. The lesion is well depicted in the B-scan ultrasonography (B) gross, and (C) microscopic (D) specimens of the tumor. Photomicrograph shows two cystic lesions within the same area, one filled with blood and the other empty. Note the aggregates of lymphocytes with and without germinal centers within the fibrous skeleton of the tumor (ls, lymphatic space).

FIGURE 14.9. (A) Lymphangioma in a 24-year-old woman causing marked axial proptosis due to multicystic tumor. The lesion is well depicted in the B-scan ultrasonography (B) gross, and (C) microscopic (D) specimens of the tumor. Photomicrograph shows two cystic lesions within the same area, one filled with blood and the other empty. Note the aggregates of lymphocytes with and without germinal centers within the fibrous skeleton of the tumor (ls, lymphatic space).

FIGURE 14.10. (A) An eyelid and anterior orbit lymphangioma prolapsing from the superior eyelid with bluish purple glistening surface. The Tl-weighted axial MR images (B,D) reveal the multiloculated tumor anterior and posterior to the orbital septum. (C) The multicystic appearance of the tumor is also seen clearly in the intraoperative photograph with yellowish, transparent cystic structures. (D) Some of the cystic structures posterior to the globe show fluid-fluid level (arrow).

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