Orbital Tumors

Alison V. Crum

Samantha F. Bordonaro

THE CLINICAL CHALLENGE

There are many types of orbital tumors or masses that can occur in and around the orbit. The diagnosis and management can vary greatly depending on the cause. Owing to the potentially slow progression of this type of orbital disease, diagnosis can be difficult, and exam findings may be extremely subtle. The urgency required in terms of identification and treatment may also vary, making it important for any type of provider to have some baseline knowledge about orbital tumors and their identification and early management.

PATHOPHYSIOLOGY

When considering the pathophysiology of orbital tumors, there are several main categories to consider. These can be broken down into several groups: inflammatory lesions, orbital cystic lesions, orbital vascular and hemorrhagic lesions, orbital peripheral nerve and other neural tumors, lacrimal gland primary epithelial tumors, orbital histiocytic tumors/pseudotumors, and neoplastic tumors (Table 29.1, Figures 29.1, 29.2, 29.3, 29.4 and 29.5).¹^,²^,³ Neoplastic tumors include lymphoid tumors and leukemia, which may be primary or secondary or represent metastases.

APPROACH/THE FOCUSED EXAM

Findings related to orbital tumors on exam may be subtle and may have developed over time, making it difficult for the patient to have noticed much change. On exam, looking at the position of the eyeballs within the face and determining whether the face appears completely symmetric is an important place to start (Figure 29.6).

In the emergency department (ED) or urgent care center, providers may have access only to rulers. However, more sophisticated devices for a more objective symmetry assessment may be available with the McCoy facial trisquare or Hertels exophthalmometer (Figure 29.7).

Assessing the patient with a “worm’s eye view” may also be helpful. This is when you have the patient look up to the ceiling and view the face from the chin looking upward (Figure 29.8).

When approaching the exam, consider “the P’s” of orbital lesions.⁴

Proptosis

Proptosis describes one eye being farther forward in the eye socket than normal. There are two types of proptosis to recognize. Axial proptosis occurs owing to thyroid orbitopathy or thyroid eye disease. You can assess firmness of proptosis with “resistance to retropulsion.” Have the patient close their eyes, and with equal pressure from your two thumbs, press gently onto their upper eyelid. The globe will move posteriorly into the eye socket. This can be described as “soft” or “no resistance to retropulsion,” like compressing a grape or cherry tomato. Patients’ upper lids with orbital

masses or thyroid orbitopathy will resist your thumb’s pressure and will feel harder, like pressing on your chin/on a bone. This can be described as “moderate to severe resistance to retropulsion.”

TABLE 29.1 Pathophysiology of Common Orbital Tumors

Orbital Tumor	Pathophysiology
Inflammatory lesions (61%)	Inflammatory lesions can often masquerade as orbital tumors and include diagnoses such as preseptal and orbital cellulitis, conjunctivitis, uveitis, and episcleritis.
Orbital cystic lesions (10%)	Orbital dermoid cysts are the most common (37%). This is a congenital lesion that forms from epithelial cells that are entrapped during embryogenesis beneath the surface epithelium, often near bony sutures. Mucoceles usually arise from frontal or ethmoid sinuses owing to chronic inflammation that invades the orbit. If pus filled, this is called mucopyocele. If children, may be from cystic fibrosis.
Orbital vascular and hemorrhagic lesions (5%)	Cavernous hemangioma: Most common benign adult vascular orbital tumor. A congenital abnormality resulting in slow growth of endothelial cell-lined vessels surrounded by a fibrous capsule. Usually become apparent during middle age and may not exhibit swelling or external signs (Figure 29.1). Arteriovenous fistulas: Occur from abnormal communications between previously normal arteries and veins. 75% occur owing to trauma, often in younger patients. 25% can occur spontaneously and are more likely in the elderly. Two forms: Carotid cavernous fistulas are considered high flow (Figure 29.2). Dural cavernous fistulas are considered low flow and often caused by systemic hypertension and atherosclerosis.
Orbital peripheral nerve tumors/other neural tumors	Orbital neurofibroma (Figure 29.3): Benign peripheral nerve tumor Often presents with proptosis, globe displacement, diplopia May be localized or plexiform. The plexiform type is always associated with Neurofibromatosis Type 1 (NF-1)
Lacrimal gland primary epithelial tumors	Lacrimal gland duct epithelial cyst (dacryops): Inclusion cyst develops secondary to occlusion of one or more of the ducts that drains from the lacrimal gland to the conjunctival fornix. Usually arises from the palpebral lobe, may be unilateral or bilateral, will often be painless and nontender.
Orbital histiocytic tumors/pseudotumors	Langerhans cell histiocytosis (eosinophilic granuloma and formerly known as Histiocytosis X) (Figure 29.4): Pathologic Langerhans cells proliferate, often with inflammatory cells (primarily eosinophils) causing local, often bony, destruction. Typically occur in the 1st decade of life and often present as swelling in the superotemporal aspect of the orbit and often accompanied by pain, redness, tenderness, rarely bilateral.
Neoplasms	Primary orbital neoplasms: Lymphoma is the most common in the orbit (Figure 29.5). Malignant proliferation of abnormal lymphocytic cells (often B-cell origin) and include the following: Extranodal marginal cell lymphoma (EMZL) a.k.a. mucosal associated lymphoid tissues (MALT) Follicular lymphoma Diffuse large B-cell lymphoma (DLBCL) Mantle cell lymphoma (MCL) Most common presenting symptoms include swelling (48%), mass (49%), and proptosis (37%). Primary intraorbital lymphomas are often associated with autoimmune disease. Orbital metastatic neoplasms: The most frequent adult metastatic cancers include breast, lung, renal cell, thyroid, and prostate cancer.