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A 15-year-old girl with sudden onset proptosis
Digital Journal of Ophthalmology 2006
Volume 12, Number 5
December 12, 2006
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| Diagnosis and Discussion | Presented is the case of a 15-year-old girl with an orbital vascular malformation who developed an orbital hemorrhage two days after minor trauma to the globe. This case illustrates an interesting acute presentation of an orbital vascular malformation, which resolved with conservative management.
Orbital vascular malformations (OVMs) are anomalies of blood vessels caused by errors of vasculogenesis. They may occur isolated within the orbit or in association with vascular anomalies elsewhere [4].
Until recently, there has been controversy regarding the classification of OVMs, which reflects a poor understanding of the origin of these lesions and may complicate treatment decisions. In 1999 the Orbital Society published a consensus statement on the terminology of OVMs [2]. Vascular malformations were classified as no flow malformations (e.g. lymphangiomas), arterial flow malformations (e.g. arteriovenous malformations) or venous flow malformations according to communications with the systemic vascular system. Venous flow malformations are weakened segments of the orbital venous system of variable complexity. This group is further classified as distensible (clinical or radiological evidence of distensibility with increased venous pressure), or nondistensible. Distensible lesions have direct and rich communication with the venous circulation and nondistensible lesions have a direct communication but to a much lesser extent.
Spontaneous orbital haemorrhage and thrombosis can occur in all types of vascular malformations but may be more common in nondistensible lesions, which have stagnant blood flow [5].
The largest study of orbital vascular malformations demonstrated the varied presentations of such lesions [6]. This retrospective series examined 158 patients with a diagnosis of orbital venous anomaly or lymphangioma. Patients may present acutely with symptoms including pain, sudden proptosis, nausea, vomiting, diplopia or visual deterioration. An acute presentation may occur following an episode of hemorrhage or thrombosis within the lesion. OVMs may also present with intermittent proptosis as distensible lesions may expand during episodes of coughing, bending, or straining. OVMs with a superficial component may produce swelling and disfigurement of the eyelids or conjunctiva. Most patients have normal vision at presentation [7].
In Wright’s series, 55% of patients had at least one orbital hemorrhage and although this could occur at any age it was more common in patients less than 30 years of age. Bleeding into surrounding tissues was frequent often resulting in bruising of the eyelids and subconjunctival tissues. Compression of the optic nerve was uncommon and in most cases vision was not permanently impaired.
Orbital CT with contrast or MRI, are reliable ways of demonstrating OVMs. CT typically shows a smooth, rounded homogenous mass denser than brain. However, OVMs can produce variable appearances depending on the flow and the evolutional stage of any haemorrhage or thrombosis within the lesion.
This case raises important questions regarding the natural history of orbital venous anomalies. The lesion in this case had remained quiescent for more than ten years, only to re-present acutely following minor trauma. OVMs tend to enlarge either at haemorrhagic intervals or progressively without haemorrhage. Interestingly the incidence of haemorrhage decreases in later life. This suggests that malformations achieve stability perhaps secondary to fibrosis.
Patients should be treated as conservatively as possible. OVMs are difficult to remove surgically due to close associations with normal orbital structures and associated orbital wall defects [8]. There is also a risk of visual loss secondary to haemorrhage or optic nerve damage secondary to vascular compromise [9].
If intervention is indicated, the least invasive method should be employed first as these lesions are benign and symptomatic treatment will usually suffice. Indications for intervention may include severe pain, hemorrhage causing severe proptosis or optic nerve compression, or a well circumscribed lesion causing a cosmetic defect or significant proptosis. Surgical options include evacuation of haemorrhage, excision, carbon dioxide laser ablation, embolisation with platinum Guglielmi detachable coils and percutaneous alcohol sclerotherapy. | |
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