Vascular tumors of the orbit

Do Minimally Invasive Approaches to Pediatric Orbital Tumors Provide an Advantage on Outcome and Efficiency?

OBJECTIVE

The present study evaluated whether minimally invasive approaches to orbital lesions could improve surgical, clinical, and aesthetic outcomes compared with more invasive ones. This is the first study specifically addressing this topic in children.

METHODS

Children consecutively operated on from January 2010 to January 2020 were analyzed. Thirty patients matched the inclusion criteria and were divided into group A: 14 cases treated with traditional surgical approaches; and group B: 16 cases managed by minimally invasive approaches.

RESULTS

There were no significant differences between the 2 groups in terms of demographic data and extent of tumor resection. Mean surgical time for the approach (40 minutes vs. 70 minutes, P < 0.0001), surgical complication such as periorbital edema (37% vs. 78%, P = 0.02) and dural tear (0 vs. 21%, P = 0.05), and procedures cost (P < 0.0001) were significantly reduced in group B. Regarding clinical outcomes, group B showed a significant reduction both in terms of postoperative pain (mean score based on visual pain scale was 2.9 vs. 4.1 P = 0.003) and mean hospitalization time (4.5 days vs. 5.5 days, P = 0.0004). The cosmetic outcome according to the Sloan classification was significantly better in group B as well (81% vs. 36% class I patients, P = 0.005).

CONCLUSIONS

The use of mini-invasive approaches to orbital tumor has clear advantages in terms of surgical, clinical, and cosmetic outcomes in comparable patients; therefore, they should be preferred whenever feasible. Craniotomic approaches remain necessary for very large tumors.

Prognosis Analysis and Clinical Features of Orbital Cavernous Venous Malformations With Refractory Insidious Onset

Objective

The present study aims to analyse the clinical presentation, treatment and prognosis of a group of patients with orbital cavernous venous malformation (OCVM) with an insidious onset.

Method

The clinical data of 35 patients with OCVM treated at our centre between 2003 and 2020 were retrospectively analysed. The OCVMs were classified as one of six types (I–VI) according to the orbital position of the tumour. The clinical characteristics, treatment methods and follow-up results were recorded.

Results

A total of 35 patients with OCVM under the optic nerve sheath in the orbital apex area or the common tendon ring (Types I and II) were included in the present study. In 20 cases (57.1%), patients were misdiagnosed with optic neuritis, and in 20 cases (57.1%), the tumour was not identified based on imaging. The presentation was acute or subacute in 23 cases (65.7%). All patients underwent surgery: transnasal surgery in 22 cases (62.9%) and craniotomy in 13 cases (37.1%). A total of 9 patients (25.7%) experienced postoperative complications, and 17 patients (48.6%) experienced vision improvement. The average patient age at first diagnosis was 43.3 ± 10.3 years, and the median follow-up period was 64.5 months. Overall, 14 patients (40%) experienced postoperative complications: postoperative blindness in 6 cases, postoperative vision loss in 8 cases and orbital apex syndrome in 7 cases.

Conclusion

Patients with Type I and Type II OCVMs are the most complex cases. They have an insidious onset and are associated with a high rate of misdiagnosis and missed diagnosis. Acute and subacute decreases in visual acuity are mainly caused by OCVM haemorrhage. The difficulty of surgical treatment and the poor prognosis of postoperative vision are characteristics of this tumour. Transnasal surgery and craniotomy can be used to remove OCVMs located in the common tendon ring or optic canal as well as those involving the intracranial area through the supraorbital fissure. Meanwhile, the orbital approach (orbitotomy) has proven to be an effective method of treating OCVMs not involving the deep orbital apex and intracranial area.

Cribra orbitalia is a vascular phenomenon unrelated to marrow hyperplasia or anemia: Paradigm shift for cribra orbitalia

The orbital phenomenon, cribra orbitalia, has long been a source of controversy, especially with regard to its nature, derivation, and relationship to anemia. Therefore, the external surfaces of orbital roofs were systematically examined microscopically in human skulls from historical collections. Superior orbital surfaces of 278 individual crania within the Hamann-Todd collection were assessed at various magnifications using epi-illumination microscopy to identify the presence of cribra orbitalia and characterize its nature. Also, 12 additional individuals with diagnosed anemia in the Hamann-Todd collection were evaluated. Orbital roof alterations, present in one-third of examined crania, had two discrete appearances: Vascular grooves (45%) and application of new bone in a vascular branching pattern on the orbit surface (55%). Porosity of the orbit was not observed. Evaluation of the orbits of 12 individuals with diagnosed anemia revealed one with a single deep defect, suggesting a space-occupying phenomenon, but no evidence of bone accretion, vascular grooves, or porosity. Cribra orbitalia has often been lumped indiscriminately as an indicator of organismal stress, rather than identified as a indicating a specific etiology. Neither that perspective nor porosity are supported by high resolution examination of orbital roof changes. Recognition of the blood vessel imprint pattern falsifies previous speculations and provides a new paradigm. The actual character of cribra orbitalia is documented and new hypotheses generated. While population prevalence of cribra orbitalia seems excessive for explanation on the basis of these hypotheses, the imprints are clearly vascular in origin.

[A rare cause of exophthalmia: intraorbital cavernous hemangioma (about a case)]

Cavernous hemangioma is the most frequent primary benign vascular tumor of the orbit in the adult; the median age of diagnosis is 42 years with a female predominance. This tumor develops slowly and has no tendency for spontaneous regression; it is electively located at the level of the retro-ocular muscular cone but it can develop in the extraconic space. Clinically it appears as progressive irreducible, non-pulsating, painless (unless there's an unexpected complication) exophthalmia, associated with decrease in visual acuity in 2/3 of cases. The diagnosis is easily confirmed by imaging, which allows to precisely locate the tumor in relation to the optic nerve and the oculomotor muscles and to indicate the type of surgical approach. Surgical resection should be complete; it is usually simple because the tumor is limited and perfectly cleavable. Surgical approach is established on the basis of tumor volume and above all of the seat of the lesion. Functional prognosis is good and recurrences are rare. We here report the case of a 44-year old patient with orbital cavernous hemangioma revealed by exophthalmia.

Use of an intravenous sclerosing foam (3% sodium tetradecyl sulfate) for treatment of orbital varix in a dog

A 6-month-old intact male Standard Dachshund was referred for evaluation of a soft tissue swelling above the right eye. Examination of the right eye revealed mild lateral deviation of the globe, normal vision, and a dorsonasal soft tissue swelling. Examination of the posterior segment was normal. Dual-phase computed tomography angiography was consistent with an orbital varix of the angularis oculi and right dorsal external ophthalmic veins with no evidence of arterial involvement. Treatment involved fluoroscopically guided coil embolization of the venous outflow with nine platinum microcoils, followed by sclerotherapy of the varix using 1.5 mL of 3% sodium tetradecyl sulfate foam. Moderate-to-marked swelling was noted at the treatment site in the weeks following therapy, which gradually resolved. At final reexamination 3 months post-therapy, complete sclerosis and resolution of the orbital varix were documented. To the authors' knowledge, this is the first reported case involving the use of a sclerotic agent for successful treatment of a venous malformation in a dog.

Periocular hemangiomas and lymphangiomas

Infantile hemangiomas are the most common benign tumor of childhood. Lymphangiomas are benign hamartomatous vascular tumors. Both lesions can be problematic when located in the periocular region. Pediatricians must be familiar with the characteristics of each which would necessitate referral to an ophthalmologist or other subspecialist for evaluation, including obstruction of the visual axis which can lead to amblyopia of the affected eye. Additional potential complications include proptosis, ocular motility limitation, optic nerve injury, and poor eyelid closure with or without corneal surface disease. All children with periocular hemangiomas or lymphangiomas should be referred to an ophthalmologist for further evaluation.

An analysis of 2,480 space-occupying lesions of the orbit from 1976 to 2011

PURPOSE

To evaluate the frequencies of orbital space-occupying lesions seen at single orbital unit in a period of 35 years.

METHODS

In this retrospective case series, the authors reviewed the medical records of 2,480 consecutive patients referred to the authors' Orbital Unit for evaluation of an orbital mass between 1976 and 2011. The final diagnosis in each case was established by a combination of history, ocular findings, diagnostic imaging, and histopathologic analysis, when available. The number and percentage of benign and malignant tumors were determinated, also according to the age of the patients and the tumor location within the orbit. This study adhered to the principles of the Declaration of Helsinki.

RESULTS

Of the 2,480 lesions, 1,697 (68%) were benign and 783 (32%) were malignant. The most frequent benign tumors were dermoid cyst (14%) and cavernous hemangioma (9%). The most common malignant tumors were non-Hodgkin lymphoma (12%), basal cell carcinoma (3%), and orbital metastases (3%). In patients younger than 60 years, benign tumors are more frequent, whereas in patients older than 60 years, the frequency of malignant tumors increased. Regarding the distribution in the orbit, the most common tumors were dermoid cyst (206 cases) in the upper-outer quadrant, mucocele (155 cases) in the upper-inner quadrant, basal cell epithelioma (35 cases) in the lower-inner quadrant, cavernous hemangioma (68 cases) in the lower-outer quadrant, and meningioma (90 cases) in central space. Most of the tumors were located in the upper-outer quadrant. In the lower-inner quadrant, malignant tumors were more frequent than benign tumors.

CONCLUSIONS

The authors' findings highlight the distinctive nature of the orbital oncology experience at an ocular oncology department.

Endoscopic endonasal resection of medial orbital lesions with intraoperative MRI

BACKGROUND

Various approaches have been described and used for operating on lesions in the orbit. The approach selection is based on the pathology in the orbit and its exact location. This study was performed to evaluate the endoscopic endonasal approach (EEA) for orbital lesions and application of intraoperative MRI (iMRI).

METHODS

Since 2006, the present authors have performed 614 endoscopic endonasal procedures. iMRI was used in 409 of these cases. Three orbital lesions approached via the endonasal route with a minimum follow-up of 1 year were analysed.

RESULTS

EEA was used in one case of intraconal cavernoma, one extraconal cavernoma and one solitary fibrous tumour in the orbit. The lesion was located medially to the optic nerve in all cases. Radical resection was achieved and the patient's vision was improved in two cases with a preoperative visual field deficit. iMRI was useful in two cases. In one case intraoperative MRI helped to find an intraconal lesion; in the other case iMRI led to evacuation of haemostatic material and blood, which was causing compression in the orbit.

CONCLUSIONS

The EEA should be considered whenever a lesion in the orbit is located medially to the optic nerve. Excellent results were achieved. iMRI proved useful in selected cases.

The role of surgical treatment in orbital vascular anomalies

BACKGROUND

The details of the surgical treatment of orbital vascular anomalies (OVAs) are not fully defined in the literature.

METHODS

Two hundred forty-nine patients who underwent surgical treatment of OVAs at our institution between January 1995 and December 2005 were included in a consecutive-series study. Each patient's clinical data, technique details, and clinical outcomes were prospectively collected. The aesthetic results were analyzed according to clinical features and treatment by using the χ (2) association test or Fisher's exact test.

RESULTS

Thirty-seven percent of the patients had OVAs involving the upper eyelid, 23% the lower lid, and 40% both eyelids. A complete resection was performed in 65.9% of the patients. A total of 379 surgeries were performed to achieve the final result. The majority of patients (98.3%) had no complaints about surgical scars. The majority of patients had no clinical treatment prior to the surgery. One or more clinical deformities were identified in association with the OVA. Those deformities included ptosis, scar sequelae due to ulceration/infection, eyelash or tarsal/ligament distortions, fibroadipose tissue residues, proptosis, or strabism. Bone deformities were present in 11.3% of the patients. A complete functional and aesthetic restoration was achieved in 66.6% of the patients.

CONCLUSIONS

Outcomes with a significant relationship to not obtain complete functional and aesthetic restoration included involvement of both eyelids, upper-eyelid involvement, older age, bilateral involvement, diffuse facial pattern OVAs, and OVAs with dimensions greater than one third of the orbit dimension.

Surgical treatment of orbital cavernomas: clinical and functional outcome in a series of 20 patients

PURPOSE

The aim of this study is to assess the efficacy and safety of surgical treatment of orbital cavernomas in terms of clinical and functional results.

METHODS

Twenty consecutive patients underwent surgical removal of a unilateral orbital cavernoma between 1999 and 2009. Indications for surgical treatment were: visual impairment, diplopia due to ocular movement impairment, progressive and disfiguring unilateral proptosis, severe retroorbital pain clearly related to the orbital cavernoma. We used a topographic classification of the lesions within the orbit. The orbit has been divided into an anterior and a posterior compartment on the axial plane and into three sectors on the coronal plane. The proptosis was quantified on MRI scans.

RESULTS

The location of the cavernoma determined the choice of the surgical approach. We performed eight lateral orbitotomies and 12 fronto-orbito-zygomatic approaches. All the tumors were completely removed as assessed at follow-up MRI. We did not record any intraoperative or major postoperative complication requiring a reoperation. The postoperative visual acuity improved in four of five patients with visual impairment, it worsened in the other case. Proptosis improved in all the patients. Diplopia improved in four patients, and did not recover in another case.

CONCLUSION

Surgical treatment of symptomatic orbital cavernomas is safe and effective. Tumor location dictates the choice of surgical approach. Visual function and cosmetic result are the main parameters to evaluate the clinical outcome. Surgical approach and dissection technique are crucial in determining the visual outcome.

Distensible superficial venous orbital malformations involving the lower eyelid in two horses

CASE DESCRIPTION

2 horses were examined because of vascular masses involving the lower eyelid.

CLINICAL FINDINGS

Both horses had a unilateral, fluctuant mass involving the lower eyelid. For horse 1, the mass had been present since birth and had slowly increased in size over time. The mass also changed in size in response to various environmental stimuli, alterations in the position of the horse's head, and digital obstruction of superficial vessels adjacent to the mass. Horse 2 was brought to the hospital for euthanasia, and no historical or antemor-tem data were available. A combination of contrast angiography, Doppler ultrasonography, surgical exploration, and blood gas analysis (horse 1) and postmortem and histologic examination (horse 2) were used to determine that the masses consisted of non-neoplastic distended venous channels with anastomoses to the inferior lateral palpebral and angularis oculi veins (both horses) as well as the facial vein (horse 2). Histologic examination (horse 2) revealed large, endothelial cell-lined, blood-filled spaces within the deep dermis consistent with a distensible superficial venous orbital malformation.

TREATMENT AND OUTCOME

Horse 1 underwent surgical exploration and ligation of the vascular malformation. Six months after surgery, the mass was markedly reduced in size, and size of the mass was static regardless of head position or environmental stimuli.

CLINICAL RELEVANCE

Thorough preoperative planning with Doppler ultrasonography, contrast angiography, and blood gas analysis is recommended when attempting surgical correction of these malformations in horses. Surgical ligation can result in a successful cosmetic and functional outcome.

Endoscopic endonasal approach to the orbital apex and medial orbital wall: anatomic study and clinical applications

OBJECTIVE

The objective of this study was to recognize the endoscopic anatomy of the orbital apex and medial orbital wall to understand the pure endoscopic endonasal approaches to this region and their clinical applications. These basic information will facilitate our surgical procedures and decrease the rate of surgical complications.

MATERIAL AND METHODS

Five fresh adult cadavers were studied bilaterally (N = 10). We used Karl Storz 0- and 30-degree 4-mm, 18-cm, and 30-cm rod-lens rigid endoscopes in our dissections. After cadaver specimen preparation, we approached each orbital apex and medial orbital wall through each nostril. After resection of medial orbital wall, an endoscopic intraorbital approach was performed.

RESULTS

The orbita could be exposed by using 0- and 30-degree endoscopes. We preferred to start the approach from the sphenoid sinus instead of transethmoidal approaches that are less familiar to the neurosurgeons. The posterior and anterior ethmoidal arteries are in close relation to the supralateral wall of ethmoid sinus, thus care must be taken not to injure these arteries during dissection. In this way, we can safely expose the whole medial wall of the orbita. Optic canal decompression can be safely done by bone resection starting from the optic nerve toward the optic canal. We continued bone resection from the posterior to the anterior of the medial orbital wall, thus we can perform medial orbitotomy. The intraorbital approach can be done medially by introducing the endoscope between the medial and inferior rectus muscles.

CONCLUSIONS

Our anatomic study offered the facility to learn the endoscopic anatomy of the orbital apex and the medial wall of the orbita and understand the appropriate approaches (such as medial orbitotomy and optic canal decompression) to some pathologic lesions of this region. With skilled and experienced hands, it can superimpose many traditional orbital approaches with minimal invasiveness and less postoperative complications.

The supraorbital approach--a minimally invasive approach to the superior orbit

BACKGROUND

We present a minimally invasive approach to the superior orbit via an eyebrow incision with a small osteotomy, minimal orbital rim resection and small frontal craniotomy.

METHODS

This approach was used in 20 patients with a well-defined intra-and extraconal lesion superior to the optic nerve, who underwent surgery between 2000 and 2007.

RESULTS

This approach is purely extradural with minimal brain and orbital retraction. The size of the lesion was not a limiting factor. Sensory deficits in the territory of the supraorbital nerve resolved within 7 months on average.

CONCLUSION

This approach presents a combination of an extra-and transcranial approach, which is indicated in all orbital lesions superior to the optic nerve. The clinical and cosmetic results are excellent.

Malignant solitary fibrous tumour of the orbit

PURPOSE

We aimed to report a case of orbital solitary fibrous tumour (SFT) in a child and to review the relevant literature.

METHODS

We describe an SFT in a 13-year-old boy with a 1-month history of painless proptosis in the left eye.

RESULTS

Magnetic resonance imaging revealed a well circumscribed mass filling most of the left intraconal orbit. The lesion was excised and histopathological examination revealed a malignant SFT. Postoperative follow-up for 18 months was uneventful.

CONCLUSIONS

Malignant SFT of the orbit should be included in the differential diagnosis of paediatric orbital tumours. Complete surgical excision remains the preferred method of management and the longterm prognosis is guarded.

[Intraorbital cavernous hemangioma]

Cavernous hemangioma is the most frequent primary vascular orbital tumor in adults. This slowly evolving lesion is usually located behind the ocular globe, between the extrinsic muscles. It leads to axial exophthalmia. Surgical treatment is indicated when there is a risk of visual impairment. The prognosis is related to the size of the lesion and its extension. CT scan is rather unspecific, but MRI is highly sensitive and specific in case of progressive painless exophthalmia.

Computed Tomographic Evaluation of Anatomic Relationship between the Paranasal Structures and Orbital Contents for Endoscopic Endonasal Transethmoidal Approach to the Orbit

Objective:

Some recent reports have described the endoscopic endonasal removal of orbital tumors. However, the surgical anatomy for an endoscopic endonasal approach has not yet been clearly described. The first aim of this study is to examine the anatomic relationship between the paranasal and orbital structures with the use of computed tomographic imaging and to find useful landmarks for a transethmoidal approach to the orbital retrobulbar space. The second aim is to determine a procedure to minimize the possibility of bleeding via the endonasal transethmoidal approach.

Methods:

One hundred axial and coronal computed tomographic scans obtained between January 2004 and December 2005 were evaluated.

Results:

The third lamella was located posteriorly to the posterior end of the eyeball on all axial computed tomographic scans, thus indicating that it may be a useful landmark for the localization of the retrobulbar space. There was a large variation in the relationship among the inferior and medial rectus muscles and the ethmoid–maxillary plate regarding their location. These results demonstrate that the route into the orbit via the ethmoid–maxillary plate gains no access to the medial side of the medial rec-tus muscle, the region with abundant blood vessels.

Conclusion:

These results suggest that the third lamella and ethmoid–maxillary plate are the most important anatomic landmarks for an endoscopic endonasal transethmoidal approach to the orbital retrobulbar space.

Transconjunctival orbitotomy for orbital cavernous hemangiomas

BACKGROUND

Orbital cavernous hemangiomas, particularly those within the retrobulbar space, are approached by neurosurgeons as well as by ophthalmic surgeons. Several surgical techniques have been applied over the past decades. Less traumatic approaches in this functionally and cosmetically important region are desirable. We describe a transconjunctival approach in 39 patients with orbital cavernous hemangiomas.

METHODS

Thirty-nine patients with orbital cavernous hemangiomas were treated with transconjunctival orbitotomy. The clinical and radiologic characteristics of orbital cavernous hemangiomas were analyzed in the course of their appropriate treatment.

RESULTS

In all patients, cavernous hemangiomas were just behind the globe or were compressing it. Computed tomography and magnetic resonance imaging showed orbital cavernous hemangiomas as round, well-defined intraconal masses. In 37 cases, the tumors were removed intact, and only 1 patient suffered permanent vision loss as a result of intraoperative hemorrhage. In the other 2 cases, the tumor fragments were incompletely removed. Visual acuity increased in 6 of the 9 cases with primary visual impairment. Thirty-two patients with primary proptosis were resolved completely. Six patients with visual field defect were also improved.

INTERPRETATION

Retrobulbar intraconal cavernous hemangiomas can be removed successfully through a transconjunctival approach. However, if the tumor is close to, or touching, the orbital apex, adhering tightly to retrobulbar tissue, or combined with large draining veins, operation through other approaches must be considered.

Giant cavernoma of the orbit: clinical and surgical considerations

Cavernous hemangiomas of the orbit are benign, hamartomatous, vascular lesions, more frequent in middle-aged women, representing the most common benign primitive neoplasm of the orbit. Several therapeutic modalities and surgical approaches have been described, in order to preserve the normal orbital structures. We describe the case of a patient with a volumous orbital cavernoma, approached by a fronto-orbito-zigotomy. A review on diagnostic modalities and surgical approaches is also presented.

Solitary fibrous tumor of the orbit: Morphological, cytogenetic and molecular features

Solitary fibrous tumor (SFT), a benign neoplasm arising in mesenchymal structures, was initially described in the pleura but subsequently has also been documented in other locations. It is uncommon in the orbit, where it closely resembles other benign spindle-shaped mesenchymal tumors of this area such as schwannoma, meningioma or hemangiopericytoma. We present a case of orbital SFT in a 34-year-old woman. The radiological study showed the presence of an enhanced uptake lesion measuring 2 cm in major diameter. The histopathological evaluation revealed alternating cellular and hypocellular areas with spindle-shaped cells. The cellular organization displayed a broad variety of irregular morphological patterns. The neoplastic cells were intensely positive for CD34 and vimentin, while S100, epithelial membrane antigen (EMA), Caldesmon, Calretinin and WT-1 proved negative. The pericellular matrix exhibited strong positivity for CD44 and collagen IV. Scarce mitotic figures, a Ki-67 nuclear labeling index of <5%, and focal expression of p53 were also observed. Measurement of DNA content revealed a DNA index of 1, indicating a diploid peak in 95% of the tumor cells. A normal 46,XX karyotype was present. No TP53 (exons 5-8) mutations or MDM2 and CDK4 amplifications were observed. No p14(ARF), p15(INK4B) and p16(INK4A) deletions or hypermethylation were observed in this benign tumor. Following surgical resection and radiotherapy, the patient showed no tumor relapse after one year of follow-up.

Removal of an orbital apex hemangioma using an endoscopic transethmoidal approach: technical note

OBJECTIVE

The posterior orbit contains a number of important and vulnerable structures, including the optic nerve, the ophthalmic artery and vein, and the ocular muscles and their motor nerves, which makes surgical access to the lesion in this region quite difficult. Transfrontal, transfrontal-ethmoidal, and transmaxillary procedures have the disadvantage of possible injuries to a number of nontumor structures, whereas an endoscopic transethmoidal approach is a minimally invasive surgery for the retrobulbar lesions. Retrobulbar cavernous hemangioma was successfully removed by a transethmoidal approach.

METHODS

Tumor removal was performed in a patient with an intraconal cavernous hemangioma of approximately 15 mm in diameter. By a transethmoidal approach, the medial-inferior part of the orbit, as well as the apex of the orbit, were clearly visualized after endonasal ethmoidectomy. After the removal of the medial orbital bone, the orbital periosteum was incised and elevated. By elevating the orbital fat, the tumor could be identified separately from the orbital contents.

RESULTS

Cavernous hemangioma at the orbital apex was removed without complications.

CONCLUSION

An endoscopic transethmoidal approach, which requires no skin incision, is a minimally invasive surgery for retrobulbar orbital tumor, leading to excellent cosmetic results with less bleeding.

Cavernous haemangioma in the orbital apex: stereotactic-guided transcranial cryoextraction

A 55-year-old Caucasian woman presented with an orbital cavernous haemangioma superior to the optic nerve in the orbital apex. Preoperative imaging demonstrated a mass involving the superomedial and superolateral quadrants of the posterior orbit. A stereotactic fronto-orbital approach was performed by the neurosurgical team, and cryoextraction of the lesion was accomplished by the ocular plastic surgical team.

Vascular Lesions of the Orbit in Children

Hemangioma and venous lymphatic malformation are the two most common orbital vascular lesions occurring in the pediatric patient. MR imaging precisely delineates and characterizes these lesions and thus plays an important role in their diagnosis and management. This article discusses the characteristic clinical and imaging findings of hemangiomas and venous lymphatic malformations and the controversies regarding the origin and nomenclature of vascular lesions.

Orbital Cavernous Hemangioma: Role of Imaging

CT and MR imaging are particularly important in the diagnostic investigation of patients with vascular disorders of the orbit. The improved image quality of CT and MR imaging, along with dynamic CT angiography, MR angiography, MR venography, and multiphase dynamic contrast CT/MR imaging, has proven useful to delineate as well as differentiate various orbital vascular lesions. This article presents the current classification of orbital vascular disorders and describes the CT/MR imaging characteristics of orbital cavernous hemangiomas and simulating lesions.

Surgical treatment of orbital cavernomas

BACKGROUND

There are numerous descriptions for the operative techniques applied in orbital lesions. We present a systematic overview of the surgical approaches, as determined by the location and extension of orbital cavernomas.

METHODS

In our study, 37 patients (12 m, 25 f, aged 21-74 years, mean 51.22 years) underwent surgical removal of their orbital cavernoma at our clinic between 1988 and 2002.

RESULTS

In ten cases the cavernoma was located in the lateral part of the intraconal space and a lateral orbitotomy was performed. Nine cavernomas were located more inferiorly and a transconjunctival approach was used. Seven cavernomas involving the optic canal, orbital apex and superior orbital fissure were operated on via an ipsilateral intradural approach. Four cavernomas of the superior orbital fissure or of the laterobasal intraconal space were approached extradurally. In one patient, a combined extra- intradural pterional operation was performed. Four patients with a lesion located medially in the posterior intraconal space were operated on via a contralateral pterional approach. One superior, medial, intraconal cavernoma was approached supraorbitally. In one cavernoma with direct contact to the sinus a transantral approach was used. The postoperative visual acuity improved in 14 of 19 cases with visual impairment, but in none with primary visual loss. Proptosis resolved completely in 21 of 27 patients. Ocular motility recovered in four of six patients, two patients with involvement of the superior orbital fissure presented with new oculomotor palsy postoperatively.

CONCLUSIONS

The location of the cavernoma determines the recommended surgical approach. Because of their tendency to lead to irreversible loss of visual acuity due to the mass effect, we favor early surgery after the onset of symptoms.

A case of orbital hemangiopericytoma in a dog

A 7-and-a-half-year-old-dog was presented with progressive unilateral exophthalmos. Computed tomography imaging revealed an orbital mass that was surgically excised by lateral orbitotomy to preserve vision. The tumor was diagnosed histologically as a hemangiopericytoma. Twelve months postoperatively there were no signs of a local recurrence. This is the first case report of a hemangiopericytoma involving the orbit of a dog.

Orbital vascular lesions. Role of imaging

Vascular lesions represent an important subgroup of orbital abnormalities; however, there is much controversy regarding their pathophysiology and nomenclature. Attempts at resolution of some of the issues have resulted in changes of names of some of the lesions (e.g., lymphangioma to venolymphatic malformation). Imaging plays an important role in delineation and characterization of these lesions. A radiologist informed about the pathophysiology and attentive to the internal architecture of the lesions shown on images, particularly MR images, often can predict the histologic diagnosis. Imaging information helps clarify some of the controversies surrounding these lesions.