What are the causes of Enophthalmos (posterior displacement of the globe of the eye) with Horner syndrome (a combination of ptosis, miosis, and anhidrosis)?

From the Guidelines

Enophthalmos in Horner syndrome is primarily caused by pseudoenophthalmos, which appears as a sinking of the eyeball into the orbit due to ptosis and elevation of the lower lid, rather than true recession of the eyeball. The causes of enophthalmos with Horner syndrome can be attributed to various conditions that damage the sympathetic nerve pathway, including stroke, tumor, trauma, or other conditions affecting the sympathetic pathway 1. Some of the key conditions that may lead to enophthalmos include:

• Developmental conditions resulting in an absent globe (anophthalmia) or small globe (microphthalmia)
• Traumatic injury to the bony orbit
• Silent sinus syndrome
• Processes that result in atrophy of the extraocular muscles
• Desmoplastic neoplastic or inflammatory processes 1 It is essential to note that enophthalmos can also be associated with other conditions, such as thyroid eye disease, IgG4-related disease, and idiopathic orbital inflammatory syndrome (IOIS), which may present with unilateral or bilateral proptosis as a clinical manifestation 1. In terms of diagnosis, imaging studies such as MRI, CT, or angiography are typically required to locate the lesion along the three-neuron sympathetic pathway 1. Pharmacological testing with drugs like cocaine or apraclonidine can help confirm the diagnosis of Horner syndrome 1. The prognosis depends entirely on the underlying cause, with some cases resolving completely if the primary condition is treatable, while others may result in permanent neurological deficits. Management of enophthalmos in Horner syndrome focuses on identifying and treating the underlying cause, rather than the enophthalmos itself. Initial treatment with prism may be helpful to manage diplopia while waiting for possible recovery, and botox, prism, or strabismus surgery may be considered for cases that do not resolve 1. The goals of surgery should be customized for the individual patient, who may be bothered to different degrees by diplopia, head tilt, and perceived tilting of the visual vertical. These interventions may help reduce both vertical and torsional diplopia, they may reduce the perceived tilting of the visual field, and in select cases they may prove successful at resolving head tilt 1.

From the Research

Causes of Enophthalmos with Horner Syndrome

The causes of Enophthalmos (posterior displacement of the globe of the eye) with Horner syndrome (a combination of ptosis, miosis, and anhidrosis) can be attributed to various factors. Some of the key causes include:

• Damage to the oculosympathetic pathway, which can be congenital or acquired 2
• Disruption along the oculosympathetic pathway, resulting from various diseases ranging from benign to life-threatening conditions 3
• Carotid dissection, which is a common cause of Horner's syndrome and can be diagnosed using magnetic resonance imaging and angiography scan of the head and neck 4
• Other underlying pathologic processes, which can be classified as central, pre- or postganglionic, depending on the anatomic location of the lesion 2

Diagnostic Approach

A targeted diagnostic strategy is advised, which may include:

• Clinical examination to predict etiology 2
• Pharmacological testing to confirm the presence of Horner syndrome and direct further testing and management 2, 3, 5, 6
• Imaging modalities, such as magnetic resonance imaging and angiography scan of the head and neck, to diagnose and localize the underlying pathology 4, 5

Key Considerations

• Horner syndrome can be a sign of a life-threatening condition, and a thorough diagnostic approach is essential to determine the underlying cause 2, 3
• A combined clinical, pharmacological, and imaging algorithm can be used to diagnose and manage Horner syndrome 5
• Pharmacologic testing can confirm the presence of Horner syndrome and direct further testing and management 6