Cavernous hemangiomas are the most common intraorbital tumors found in adults. These benign, vascular lesions are slow growing and can manifest as a painless, progressively proptotic eye. Most of these tumefactions are exceedingly unilateral. Bilateral cases have been reported but are rare.
Orbital cavernous angiomas can increase intraorbital volume with a resultant mass effect. Although cavernous hemangiomas are histologically benign, they can encroach on intraorbital or adjacent structures and can be considered anatomically or positionally malignant. Visual acuity or field compromise, diplopia, and extraocular muscle or pupillary dysfunction can result from compression of intraorbital contents by the angioma. Lagophthalmos can result in exposure keratopathy, keratitis, and corneal perforation.
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Henderson reported an incidence of 4.3% among orbital neoplasms.[1]
The morbidity associated with cavernous hemangiomas is the threat of compressive optic neuropathy, extraocular muscle dysfunction, and cosmetic disfigurement.
Mortality can result from intraoperative complications, such as bleeding and the risk of general anesthesia.
No predilection exists for race or ethnicity.
Harris and Jakobiec found a 7:3 occurrence ratio of women to men, while Henderson reported an almost equal ratio, 8:7 in women and men.[2, 1]
Patients usually manifest symptomatically during the third to fifth decades of life.
Patients who present with clinically significant cavernous hemangiomas usually are middle-aged. Some of the more salient clinical symptoms are listed below.
Patients commonly describe a painless, slowly progressive protrusion or bulging of their globe accompanied by mild eyelid fullness.
A change in visual acuity secondary to induced hyperopia or reduction of the myopic refractive error can result from an anteriorly directed mass effect. In some cases, a compressive optic neuropathy can be the etiological basis for the visual acuity or field disturbance.
Extraocular muscle dysfunction and the resultant diplopia secondary to extraocular muscle impingement can cause a patient to seek consultation.
Some patients may describe the feeling of something next to or behind their eye and describe swelling or fullness of their upper lid.
Rarely, a patient harboring a cavernous angioma may describe gaze-evoked amaurosis fugax or headache.
Zauberman and Feinsod described a pregnancy-induced increase in symptomatology.[3]
Performing a complete ophthalmologic examination on patients is beneficial.
As with any examination, a thorough history and review of symptoms is paramount in formulating a comprehensive list of differential diagnoses.
Examination of patients should commence with an observation of facial features, noting any asymmetry or scarring. Palpation of the lids and globes allows one to assess differences in lid fullness and increased resistance to retropulsion. Hertel exophthalmometry can detect axial proptosis and should be documented for comparison on follow-up visits.
Visual and color acuities, as well as visual fields, should be assessed, followed by testing of pupillary and extraocular muscle function. Decreased color vision, visual field deficits, and relative afferent pupillary defects warrant immediate imaging to rule out a compressive optic neuropathy. Additionally, any extraocular motility disturbance should be quantitated with prismatic measurements.
Rarely, slit lamp or penlight evaluation may find dilated and tortuous epibulbar vessels, an epibulbar cherry-red spot, or a darkening over insertions of extraocular muscles.
Dilated funduscopic examination may elucidate choroidal folds secondary to compression of the globe by the mass. If the tumefaction is in close proximity to the optic nerve, visible changes may include edema, elevation, pallor, and even atrophy in severe cases.
CT scan detects an oval or round shaped, sharply marginated, homogenous lesion. Uptake of contrast medium by this tumefaction is highly variable and has limited diagnostic value. Computerized tomography should not be solely relied upon since it does not allow one to make a definitive diagnosis.
Ultrasound study can find a uniform high-echogenicity on A-scan. These reflections are secondary to the septae found within the lesion. Doppler flow study may reveal subdued blood flow within the angioma.[4]
Histopathologic study finds engorged vascular channels, which are tightly knit and separated by fibrous septae. These channels can have diameters measuring 1 mm and are lined by a single layer of endothelial cells.
Most cavernous angiomas require no intervention. If surgical extirpation is indicated, the approach to the orbit is dictated by tumor location within the orbit.[5]
Most cavernous angiomas are found between the optic nerve and extraocular muscles within the intraconal space. A lateral orbitotomy, or a variant thereof, is a typical approach. Tumors within the medial aspect of the orbit are approached best through an upper eyelid or a transcaruncular-based medial orbitotomy. Additionally, an anterior orbitotomy via a lower eyelid transconjunctival approach can be used. This approach was used for removal of intraconal hemangiomas extending to the orbital apex.[6]
See the images below.
View Image | MRI demonstrates enhancing mass in apex of left orbit. White arrow points to the superior portion of the optic nerve, showing its deviation. Mass was .... |
View Image | In A, final preoperative visual field of same patient as in Media file 2, demonstrating significant inferior altitudinal field loss; in B, postoperati.... |
View Image | Intraoperative photo of same patient as in Media file 2. Neurosurgical service performed craniotomy and decompression of the superior orbital fissure .... |
After adequate exposure, a well-circumscribed, purple, encapsulated lesion is seen with distinct vessels on its surface. Gentle blunt dissection allows for en-bloc removal after all vessels have been identified and cauterized with bipolar cautery.
See the image below.
View Image | Extirpation of an orbital cavernous hemangioma. Note en bloc removal and preservation of capsule. Courtesy of Robert Alan Goldberg, MD. |
The cryoprobe allows for removal of well-circumscribed lesions, reducing the incidence of capsular rupture and bleeding, making it an ideal tool for hemangioma extirpation. A disadvantage of the cryoprobe is that adjacent orbital structures also may be frozen, as is the case with deep orbital tumors.
Use of the carbon dioxide laser or Nd:YAG laser is another modality for the surgeon faced with the task of tumor removal.
Gamma knife surgery has been used with success. Liu et al found gamma knife surgery to be an effective treatment in 23 patients with orbital cavernous hemangiomas.[7]
If the cavernous hemangioma has an intracranial component or extends to facial structures outside the orbit, neurosurgical or otolaryngologic consultation should be sought.
Most patients with cavernous hemangiomas can be observed clinically with semiannual or annual formal visual field testing and dilated funduscopic examinations.
Complications are related to the angiomas mass effect within the orbit. Axial proptosis, extraocular muscle dysfunction, and compressive optic neuropathy are the sequelae that can transpire secondary to enlarging cavernous hemangiomas.
Most cavernous hemangiomas remain stable throughout a patient's life and cause no visual compromise.
If surgical intervention is warranted, most lesions excised in the hands of an experienced surgeon have an excellent prognosis and result in a low morbidity. There is no recurrence following excision or risk of malignant transformation.
Patients should have a clear understanding of the immediate need for follow-up care if a visual disturbance occurs or if proptosis increases significantly.
MRI demonstrates enhancing mass in apex of left orbit. White arrow points to the superior portion of the optic nerve, showing its deviation. Mass was pressing on superotemporal optic nerve and displacing it inferomedially at apex. Patient had 6 months of progressive decreased vision and visual field loss. Courtesy of M. Duffy, MD, PhD.
In A, final preoperative visual field of same patient as in Media file 2, demonstrating significant inferior altitudinal field loss; in B, postoperative visual field at approximately 3 weeks after orbital apex decompression and removal of mass; and in C, postoperative visual field at approximately 6 months.
Intraoperative photo of same patient as in Media file 2. Neurosurgical service performed craniotomy and decompression of the superior orbital fissure and optic canal (yellow arrows) at request of ophthalmology service. Orbital surgery service then opened the periorbita over a bulge (double black arrows) between optic nerve and cranial nerves (single black arrow) and bluntly dissected out mass. Pathology confirmed mass as a cavernous hemangioma. Cranial nerves V and IV were adhered, and careful blunt separation was performed. Postoperatively, a small left hypertropia resolved over 6 weeks. Courtesy of M. Duffy, MD, PhD.
MRI demonstrates enhancing mass in apex of left orbit. White arrow points to the superior portion of the optic nerve, showing its deviation. Mass was pressing on superotemporal optic nerve and displacing it inferomedially at apex. Patient had 6 months of progressive decreased vision and visual field loss. Courtesy of M. Duffy, MD, PhD.
In A, final preoperative visual field of same patient as in Media file 2, demonstrating significant inferior altitudinal field loss; in B, postoperative visual field at approximately 3 weeks after orbital apex decompression and removal of mass; and in C, postoperative visual field at approximately 6 months.
Intraoperative photo of same patient as in Media file 2. Neurosurgical service performed craniotomy and decompression of the superior orbital fissure and optic canal (yellow arrows) at request of ophthalmology service. Orbital surgery service then opened the periorbita over a bulge (double black arrows) between optic nerve and cranial nerves (single black arrow) and bluntly dissected out mass. Pathology confirmed mass as a cavernous hemangioma. Cranial nerves V and IV were adhered, and careful blunt separation was performed. Postoperatively, a small left hypertropia resolved over 6 weeks. Courtesy of M. Duffy, MD, PhD.