Acute spontaneous extraconal hematic cyst of the orbit

Abstract

A 49 year old man presented with one day history of mild right eye pain and proptosis. There was no definite history of trauma. On examination there was limitation of movement in all directions of gaze and 6 mm proptosis of his right eye. CT scan showed extraconal lesion compressing the optic nerve and inferior rectus muscle. Right inferior conjunctival fornix based approach was performed with lateral canthotomy and inferior cantholysis and exploration revealed a cyst containing blood which was removed.

1. Introduction

Several terms have been used in the literature to describe cystic blood collection in the orbit, including hematic cyst, hematocele, blood cyst, hematoma and chocolate cyst (Amrith et al., 1990; Goldberg et al., 1992; Iwata et al., 2000).

Hematic cyst of the orbit may result from trauma or blood diseases or it may occur spontaneously (Amrith et al., 1990; Goldberg et al., 1992; Iwata et al., 2000).

Herein, we describe a case of non traumatic extraconal orbital hematic cyst with acute onset which was removed through the inferio-orbital approach.

2. Case report

A 49 year old man presented with mild eye pain and protrusion of his right eye for one day duration. There was no history of trauma or bleeding disorder. Physical examination revealed visual acuity of 20/20 in both eyes, normal ocular pressure and no afferent pupillary defect. There was marked limitation of ocular movements in all directions of gaze (Fig. 1) and 6 mm proptosis of his right eye. The bleeding profile was normal.

Figure 1.

External photographs of a 49 year-old man showing limitation of movement of the right eye and proptosis.

Funduscopic examination showed optic disc swelling of the right eye.

A computerized tomography (CT) scan showed homogenous extraconal lesion compressing the optic nerve and inferior rectus muscle (Fig. 2). Magnetic resonance imaging (MRI) showed elevation of the right inferior rectus muscle by extraconal lesion (Fig. 3).

Figure 2.

Contrast enhanced CT scan of the orbit (A) axial, (B) coronal and (C) sagittal showing right sided proptosis and an oblong shaped extraconal soft tissue mass displacing the right inferior rectus muscle with no bony changes.

Figure 3.

MRI of orbit (A) coronal T1WI, (B) sagittal T1WI, (C) coronal T2WI and (D) post contrast T1WI: oblong shape extraconal mass of high signal intensity in T1WI and of low signal in T2WI due to blood content with elevation of the right inferior rectus muscle with no contrast enhancement of the mass.

The patient underwent inferior conjunctival fornix based approach with lateral canthotomy and inferior cantholysis, after dissecting in the subperoistal space the periosteum was opened below the localized area, blood clot was exposed, which appeared dark brown in colour (Fig. 4). A biopsy of the wall was taken and histopathology revealed mostly blood clot and small foci showing fragment of fibroadipose tissue with inflammation.

Figure 4.

Hematic cyst.

3. Discussion

Hematic cyst of the orbit is classified in different ways, it can arise acutely or chronically. It can be spontaneous or secondary to trauma or blood disease.

The cyst can be with epithelial or endothelial lining or without epithelial or endothelial lining (pseudocapsule). It can also be classified according to the location as subperiosteal, extraconal and intraconal. The most common site for hematic cyst is the orbital roof.

Hemorrhage into a preexisting lesion, such as a lymphangioma, dermoid, or hemangioma is usually referred to as a chocolate cyst or blood cyst (Amrith et al., 1990; Goldberg et al., 1992; Iwata et al., 2000; Kersten et al., 1988; Mund, 1981).

Hematic cyst may occur as the result of traumatic fat necrosis which leads to the development of a cavity into which there may or may not be hemorrhage (Amrith et al., 1990; Goldberg et al., 1992; Iwata et al., 2000).

The spontaneous hematic cyst can be secondary to bleeding disorder or strain that increases the pressure in the jugular veins. As there are no valves in these veins, this unobstructed pressure is transmitted to the vessels of the skull and may cause an orbital hemorrhage (Pearson et al., 1986; Shapiro et al., 1986).

Most of the cases described have been post-traumatic. Our case shows spontaneous hematic cyst with acute onset which is very rare.

Post-traumatic hematic cysts are typically chronic and located Subperiosteally (Kersten et al., 1988; Shapiro et al., 1986).

Chronic hematic cysts account for less than 1% of all orbital tumors (Shapiro et al., 1986). Painless and nonprogressive unilateral proptosis is a common sign of chronic hematic cyst (Iwata et al., 2000).

Hematic cyst can be differentiated from cavernous hemangiomas by the absence of endothelium lining of the wall. The wall of cavernous hemangiomas is lined by endothelium (Yoshikawa et al., 2009).

The best way to treat patients with chronic hematic cyst is surgical excision (Iwata et al., 2000). Other modality of treatment includes needle aspiration but it is not recommended due to unknown nature of lesion.