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PubMed2004

On the relationship between orbit orientation and binocular visual field overlap in mammals.

The orbital apertures of Primates are among the most convergent (i.e., facing in the same direction) among mammals. It is often assumed that orbit convergence is associated with binocular visual field overlap and stereoscopic depth perception in primates. Likewise, it is also assumed that orbit orientation reflects the shape of the visual field across mammals. To date, however, no study has demonstrated that orbit and visual field orientation are correlated, much less comparable, across mammals. In this study, data on orbit convergence were collected for a representative sample of mammals for which data on the extent of the visual field are available. Both standard and phylogenetically controlled comparisons were made. The results demonstrate that orbit convergence and binocular visual field overlap are significantly correlated and display a linear relationship. Based on orbit convergence, Primates as a group have the largest binocular visual fields among mammals.

Adaptation, Physiological↗

PubMed2002

Reference values of fetal orbital measurements by transvaginal scan in early pregnancy.

OBJECTIVE: To construct reference ranges of orbital diameters, measured in early pregnancy by transvaginal sonography. METHODS: The study group consisted of 2717 fetuses of pregnant women referred to our center and examined by transvaginal ultrasound between 11-16 week's gestation. Nomograms with confidence intervals (5th and 95th percentile) for each orbital measurement (orbital diameter, interocular and binocular distance) versus gestational age were produced. RESULTS: The orbital measurements increased in a linear fashion throughout early pregnancy with a good correlation with gestational age. CONCLUSION: Transvaginal sonography is able to visualize and measure orbital diameters with accuracy in early pregnancy; reference ranges were developed that can be used to evaluate normal orbital development and can be helpful in the detection of syndromes with orbital growth defects and other associated fetal anomalies.

Adult↗

PubMed2006

Neurosurgical concepts and approaches for orbital tumours.

Orbital tumours are lesions that appear within the orbital craniofacial borders. To this end, treatment of these tumours is assured by teams of different specialists. Furthermore, these pathologies are different in adults and in children. We have endeavoured, in this chapter, to highlight the specifically neurosurgical features of orbital tumours or, to be more precise, tumours affecting the posterior two thirds of the orbit and tumours originating in or intruding into the optic canal. The list of aetiologies is long. After recapitulating the main types of tumour (as well as those of most concern), we have also studied the different stages of surgery, namely approaches and reconstructions which we have illustrated at each stage by a tumour that, in our view, seemed emblematic of the problem in question: the lateral eyebrow approach for schwannoma and cavernous angioma, the transorbital subfrontal approach for optic nerve glioma, the pterional and orbital approaches for spheno-orbital meningioma, problems with reconstruction and with plexiform neurofibroma affecting the orbit and fibrous dysplasia of bone.

Adult↗

PubMed1996

CT assessment of orbital volume in late post-traumatic enophthalmos.

The potential of CT to facilitate preoperative planning of reconstructive maxillofacial surgery by orbital volume quantification was analysed in 11 patients with traumatic enophthalmos as a late sequela of zygomatic fractures. We carried out biplanar CT examination of the orbits, and calculated total orbital and fat volumes for the healthy and enophthalmic sides. Displacement of the orbital floor and lateral wall was present in 11 and 7 cases respectively. Indentation of the medial wall was noted in 9 cases. Quantitative evaluation of the orbital cavity revealed a significant increase (P < 0.0188) in total volume on the enophthalmic side, the difference between the two sides ranging from 9.2% to 36.4%, mean 17.9%. The degree of enophthalmos, measured radiologically as 2.5-5 mm, correlated with the increase in orbital cavity volume (P = 0.000076). Enophthalmos was 2.5-3 mm in 7 cases (63.6%) and 3.5-5 mm in 4 (36.4%). This corresponded with a mean increase in orbital volume of 3.4 ml (12.3%) and 7.1 ml (27.8%) respectively. Fat atrophy was not an aetiological factor in the production of post-traumatic enophthalmos.

Adult↗

PubMed1994

Immunoglobulin A in Graves' orbital tissue: deoxyribonucleic acid amplification by polymerase chain reaction.

A role for IgA autoantibodies in Graves' ophthalmopathy is suggested by the presence of immunoglobulins of this class in Graves' orbital tissue, as detected by immunohistochemistry. We, therefore, investigated the possibility of using the polymerase chain reaction (PCR) to amplify IgA immunoglobulin genes from plasma cells infiltrating Graves' eye tissue. Template cDNA was reverse-transcribed from orbital muscle (M) mRNA of one patient (#7) and from orbital connective tissue/fat (F) mRNA of two patients (#1 and #7), both undergoing surgery for exophthalmos because of severe infiltrative ophthalmopathy. Preliminary studies to establish the PCR procedure were performed for kappa light chain DNA amplification. With the very small amount of orbital tissue template available, the sensitive "hot start" modification of the PCR was necessary to amplify significant amounts of kappa light chain DNA. Using this procedure, IgA heavy chain DNA was amplified from both connective tissue/fat (F7) and muscle (M7) cDNA of patient #7. The DNA yield was less for IgA than for IgG using the same template. There was no significant IgA (or IgG) DNA product using the connective tissue/fat cDNA of patient #1. While not implying that IgA-infiltrating plasma cells are specific for Graves' orbital tissue, our studies nevertheless demonstrate the feasibility of amplifying the genes coding for IgA antibodies from Graves' orbital tissue plasma cells. Expression of these immunoglobulin genes in future studies will make it possible to determine the antigen specificity of the antibodies expressed by Graves' orbital tissue plasma cells.

Aged↗

PubMed2006

Paranasal sinus inflammation and non-specific orbital inflammatory syndrome: an uncommon association.

OBJECTIVES: The aim of this study is to present a series of patients with orbital inflammatory symptoms associated with significant paranasal sinus inflammation, and to discuss the diagnostic and management modalities. METHODS: A retrospective, non-comparative, interventional case series of all patients diagnosed with orbital inflammatory syndrome and significant sinus inflammation, seen at two Orbital Units between January 1999 and October 2005. The clinical records of all patients were reviewed. RESULTS: Of 91 cases diagnosed with non-specific orbital inflammatory syndrome, six (6.6%, four males, two females mean age 51+/-17 years) had significant sinus inflammation. Symptoms and signs were periorbital swelling and erythema, proptosis, globe displacement and ocular motility restrictions with diplopia. On imaging, there was extraocular muscle enlargement and/or orbital fat haziness, as well as almost complete ipsilateral maxillary sinus opacification with varying degrees of opacification of adjacent sinuses. Sinus biopsy in four cases showed a non-specific inflammatory reaction. Treatment with steroids alone (four cases) or a combination of oral antibiotics and systemic steroids (two cases) resulted in resolution of signs and symptoms within 24-72 h. One case of recurrence was noted during a mean follow-up period of 9 months (range, 3-24 months), and this responded well to oral steroids. CONCLUSION: Although uncommon, paranasal sinusitis can be associated with a non-specific orbital inflammatory syndrome. When an infectious etiology is excluded, systemic steroids may play a major role in the management of these patients and result in prompt resolution of orbital signs and symptoms.

Adult↗

PubMedDate not supplied

Isolated caruncular approach for orbital decompression.

PURPOSE: To evaluate the effectiveness of the isolated caruncular approach to orbital decompression of thyroid ophthalmopathy. METHODS: In a retrospective, noncomparative, interventional case series, we reviewed the records of 29 patients (48 orbits) who had thyroid ophthalmopathy and had undergone orbital decompression using the caruncular approach. The medial wall was decompressed in two patients (three orbits), and the medial and inferior walls were decompressed in 27 patients (45 orbits). RESULTS: The mean retrodisplacement achieved was 2.7 mm of decompression of the medial wall, and 4.2 mm of decompression of the medial and inferior walls. Diplopia arose in the primary position in 4 of 17 previously asymptomatic patients. Persistent postdecompression strabismus was managed successfully with adjustable strabismus surgery. Other complications were minimal, including a hypertrophic scar in one eye and a pyogenic granuloma in another. CONCLUSIONS: Orbital decompression using the isolated caruncular approach offers rapid access to the medial and inferior orbital walls and makes graded decompression possible in each case. It is a useful approach for patients wishing surgery for cosmetic purposes and for those with compressive optic neuropathy as well.

Adolescent↗

PubMedDate not supplied

Posterior aspect of the orbital septum is reinforced by ligaments.

PURPOSE: To investigate the ligaments reinforcing the posterior aspect of the orbital septum. METHODS: Sixteen upper eyelids of eight cadavers of Asians were dissected. Ten were subjected to gross dissections to investigate the ligaments attached to the posterior aspect of the orbital septum and to investigate the relationships with the associated ligamentous structures, and six were used for histological sections to elucidate the ligament anchoring sites in the septum. RESULTS: The ligaments were attached to the posterior aspect of the orbital septum in both upper and lower eyelids in all cases. Some septa in the upper eyelids were supported by the lower-positioned transverse ligament in the lateral area. In all cases, part of the Lockwood ligament was attached to the posterior aspect of the orbital septum in the lower eyelids. Histologically, the ligaments were anchored to the posterior aspect of the orbital septum. CONCLUSIONS: The ligaments were attached to the posterior aspect of the orbital septum. These ligaments, in cooperation with the associated ligaments, are thought to complement the fragility of the orbital septum.

Aged↗

PubMed2003

Orbital inflammation.

Orbital inflammation is a common problem in adults and children, accounting for the majority of all orbital processes. The presentation may be acute, subacute, or insidious. When the onset is acute, the process can be mistaken for orbital cellulitis. In insidious cases, such as the sclerosing subtype of inflammation, the chronic painless course may prompt concerns about a neoplastic infiltration such as lymphoma. Orbital inflammation can be divided into nonspecific, idiopathic, and other specific diagnoses. The differential diagnosis includes allergic, infectious (fungal, mycobacterial, and parasitic), and neoplastic (lymphoma or metastatic) disease. Orbital inflammation impacts neurologists and neuro-ophthalmologists because all of the entities can cause afferent dysfunction (decreased vision, abnormal color perception, afferent pupillary defect, and visual field defect) and dysmotility. The pattern of motility deficit may mimic the more familiar cranial nerve palsies. Advances in the diagnosis and management of nonspecific orbital inflammation and the specific entities that cause orbital inflammation are discussed.

Diagnosis, Differential↗

PubMed1984

Orbital recurrence of choroidal melanoma 20 years after enucleation.

A 54-year-old woman developed an orbital mass 20 years after enucleation of the left eye for a choroidal melanoma, which proved to be of spindle-A type. Computed tomography of the orbit suggested the diagnosis of a cavernous hemangioma, but orbital biopsy confirmed the diagnosis of recurrent malignant melanoma and the patient was managed by orbital exenteration followed by radiotherapy. The orbital recurrence was of the mixed cell type, suggesting a gradual 20-year transition of the spindle-A cells to spindle-B and epithelioid cells. We recommend that the selected surgical management of extrascleral extension of uveal melanomas be determined by the degree of extrascleral involvement and by whether the extrascleral extension is discovered clinically, at surgery, or in the pathology laboratory. We recommend that orbital computed tomography be performed periodically after enucleation in all patients who have orbital extension of uveal melanomas.

Choroid Neoplasms↗

PubMed1990

Cutaneous approaches to the orbital skeleton and periorbital structures.

Multiple cutaneous approaches to both the superior and inferior orbit have been reviewed. Incisional choices are optimally based on both facial esthetics and orbital function, which are achieved by an understanding of the unique anatomy of this region. The superior orbit is best approached by a blepharoplasty (lid crease) incision in conjunction with a lateral extension if additional exposure is necessary. Almost all aspects of the bony orbit can be reached with the exception of the frontal bone superior to the supraorbital rim. When wide exposure of the orbital skeleton is necessary, a bicoronal scalp flap is most effective in a nonalopecic patient. The inferior orbit can be approached by a ciliary, blepharoplasty, or conjunctival incision with a lateral canthotomy. None has proven esthetic advantages over the others, with the exception of the conjunctival incision when used alone. The lid incisions must be used with the understanding that orbital function must be assessed both pre- and postoperatively and meticulous attention paid to protection and care of the anterior globe. In addition, because of the thinness of the tissues being manipulated, edema, bruising, and final settling of lid form may require more postoperative time than is typical of more peripheral approaches.

Conjunctiva↗

PubMed1993

Radiotherapy is successful treatment for orbital lymphoma.

PURPOSE: To describe the clinical presentation, treatment technique, outcome and complications in a large single institutional experience using radiotherapy for treatment of orbital lymphoma. METHODS AND MATERIALS: Twenty-five patients with lymphoma of the orbit or ocular adnexa were treated with radiotherapy at Stanford University Medical Center during the fourteen year period, 1977-1991. Patients were staged using the Ann Arbor criteria with chest x-ray, computerized tomography of abdomen and orbits, lymphangiogram, and bone marrow biopsy. Patients with disease localized to the orbits as well as those with disseminated disease and symptomatic orbital lesions were treated. Thirty-one involved eyes were treated. Mean radiotherapy dose was 35.3 Gy, with a range of 28 Gy to 40.2 Gy. Lens protection was used in all cases. Two patients with diffuse large cell lymphoma also received chemotherapy as part of their initial treatment. Follow-up ranged from 10 months to 13 years, with a mean follow-up time of 4 years. RESULTS: Twenty patients had disease confined to one or both orbits (Stage I). One patient had a monoclonal atypical infiltrate, while the remainder had a histologic diagnosis of malignant lymphoma: diffuse small lymphocytic, 13; follicular mixed, 3; diffuse small cleaved, 3; diffuse large cell, 2; follicular small cleaved, 1; follicular and diffuse small cleaved, 1; undifferentiated, 1. Two local relapses occurred; the actuarial 5-year freedom from local relapse is 89%. Actuarial 5-year freedom from distant relapse, freedom from any relapse and overall survival are 77%, 70%, and 93%, respectively. Acute complications of treatment were mild. Late complications included transient cystoid macular edema (one patient), asymptomatic subcapsular and medial sector cataract formation (two patients), retinopathy (two patients), mild eyelid retraction (one patient), and dry eye with secondary conjunctivitis (one patient). CONCLUSION: Carefully planned radiotherapy with lens shielding is an effective and safe treatment in the management of orbital lymphoma. We recommend megavoltage radiation doses of 30-35 Gy in 180-200 cGy fractions for low grade lesions, and 36-40 Gy for intermediate and high grade lesions.

Adult↗

PubMedDate not supplied

CT values in orbital hydatid cyst.

The CT values of 15 cases of orbital hydatid cyst operated upon by the author were reviewed. It was found that hydatid cyst of the orbit has high CT value, contrary to the low CT value of nonorbital hydatid. This discrepancy was confirmed by an experiment using human skull and two balls simulating hydatid cyst. One ball was put in the orbit and the other in the cranial cavity. When the skull was CT scanned it was found that the orbital ball CT value was about five times higher than the cranial ball, in spite of the fact that both balls had the same content. It was concluded that the orbital bony pyramid is the cause of this high CT value in orbital hydatid. Hence it is recommended that an orbital lesion with a high CT value can be a hydatid cyst.

Adolescent↗

PubMed2004

Treatment and long-term outcome of patients with orbital cavernomas.

PURPOSE: To evaluate the long-term prognosis of visual function in patients with orbital cavernomas after conservative and surgical treatment. DESIGN: Interventional case series. METHODS: The authors describe the outcome of 20 patients with cavernous hemangiomas of the orbit treated in their departments between 1988 and 2003. This prospective study included five cases followed by clinical and radiologic observation and 15 cases of symptomatic tumors that were completely removed by means of a frontotemporal or by means of a transconjunctival approach. The clinical characteristics of orbital cavernomas were analyzed together with their appropriate treatment. Furthermore, the authors present the unusual case of a patient suffering from progressive visual deterioration from a cerebral cavernoma compressing the optic nerve. RESULTS: The follow-up period was between 3 and 10 years. All orbital cavernomas in the group of conservatively managed patients remained stable. The transconjunctival excision of a medially located lesion was uncomplicated. The frontotemporal approach was chosen for large tumors situated in the proximity of the orbital apex and was associated with a higher number of complications. A good overall outcome of visual function and patient satisfaction was achieved in 11 of 14 cases operated on by craniotomy. CONCLUSION: The combination of clinical signs and magnetic resonance imaging (MRI) is highly sensitive and specific for the diagnosis of orbital cavernomas. In the presence of visual deterioration clearly attributable to the tumor we recommend immediate surgery, while lesions producing solely exophthalmos can safely be followed by observation. The transcranial approach offers excellent exposure and a rewarding cosmetic result and may be considered for large lesions superior and medial to the optic nerve, especially if they involve the orbital apex.

Adult↗

PubMed2006

Primary orbital melanoma treated with iodine-125 plaque radiotherapy.

PURPOSE: To report a case of primary orbital melanoma successfully managed by custom-designed iodine-125 plaque. DESIGN: Case report. METHODS: A 59-year-old man with no systemic or secondary melanocytic tumor was diagnosed with primary orbital melanoma after transconjunctival incisional biopsy. He was treated with unshielded iodine-125 plaque (90 Gy) that was sutured to the sclera. The radiation plan was calculated to safely target the initial tumor volume and any residual intrascleral or loose orbital melanoma cells that could have been disseminated to the surrounding orbital tissues during incisional biopsy. RESULTS: After 66 months' follow-up, the patient was still alive with partial remission of his liver metastases. Routine orbital magnetic resonance imaging studies confirmed the lack of orbital recurrence. CONCLUSIONS: Plaque radiotherapy appears to be a reasonable alternative to exenteration or external irradiation for orbital melanoma after biopsy confirmation.

Brachytherapy↗

PubMed2005

Orbital complications of functional endoscopic sinus surgery: MR and CT findings.

AIM: To describe the radiological findings of ophthalmic complications during functional endoscopic sinus surgery (FESS) and correlate them with the clinical manifestations and mechanisms of injury. METHODS: This was a retrospective review of the clinical and cross-sectional imaging findings of 9 patients with orbital complications during FESS. RESULTS: The most common site of entry into the orbit during FESS was the lower medial orbital wall (7 of 9), followed by the inferior orbital wall, resulting in injury to the medial rectus (4 of 9) and, less frequently, the inferior rectus (2 of 9) or superior oblique muscles (1 of 9). Extensive scarring on imaging (3 of 9) was associated with global ocular motility dysfunction. In contrast, localized scarring (3 of 9) or extraocular muscle trauma (6 of 9) resulted in disturbance of eye movement in the direction of gaze from the injured site. CONCLUSIONS: Orbital magnetic resonance and computed tomography findings correlate very well with the abnormal eye movements clinically observed, and can assist in clarifying the cause of injury and guide surgical corrective management of patients suffering orbital complications from FESS. Radiologists should be familiar with the recent developments in FESS instrumentation as well as with the most commonly injured structures within the orbit.

Adolescent↗

PubMed2005

MRI patterns in orbital malignant lymphoma and atypical lymphocytic infiltrates.

OBJECTIVE: To evaluate the potential of MRI in differentiating between malignant lymphomas and atypical lymphocytic infiltrates in the orbit. MATERIALS AND METHODS: MRI, clinical and histopathological findings in 30 patients presenting with orbital lymphoproliferative diseases (malignant lymphoma and atypical lymphocytic infiltrates) were evaluated. RESULTS: MRI detected 28 out of 30 (93%) orbital lymphoid tumors. Seven out of eight (87.5%) atypical lymphocytic infiltrates and 21/22 (95.4%) of malignant lymphomas were detected. One conjunctival malignant lymphoma and one conjunctival atypical lymphocytic infiltrate were missed. Only malignant lymphoma lesions were hyperintense compared to the extraocular muscles on precontrast and postcontrast T1-weighted images. The lacrimal duct was involved only with malignant lymphoma. Bilateral disease was more likely to be malignant lymphoma. Intraconal lesions were more likely to be associated with lesions elsewhere. No malignant lymphoma involved the extraconal fat. Only intraconal atypical lymphocytic infiltrates had indistinct margins. CONCLUSION: In the orbit, MRI features alone may not allow clear-cut differentiation of malignant lymphomas from atypical lymphocytic infiltrates. However, certain imaging features increase the likelihood of distinguishing them. MRI may miss conjunctival disease. Both orbits should be imaged when orbital lymphoid disease is a probability. The presence of intraconal disease should prompt a search for lesions elsewhere. The use of a head coil instead of a superficial coil may be advantageous by eliminating coil shine effect and allowing evaluation of both orbits. Comparison of lesion signal to extraocular muscle signal appears to be a better alternative than cerebral gray matter or periorbital fat in differentiating malignant lymphoma from atypical lymphocytic infiltrates. Since imaging findings overlap, histopathological diagnosis is necessary in all cases.

Adult↗

PubMed2004

Simultaneous intracranial and orbital complications of acute rhinosinusitis in children.

OBJECTIVE: To evaluate the frequency of intracranial and orbital complications occurring as simultaneous but separate complications of acute rhinosinusitis in the pediatric population. METHODS: Records of children admitted to St. Louis Children's Hospital between 1 January 1990 and 31 December 2002 were reviewed. Relevant literature was reviewed with the assistance of Medline. RESULTS: We identified 74 patients with orbital complications related to acute rhinosinusitis. A bimodal age distribution was identified with one group above and one group below the age of 7 years. The frequency of intracranial complications in pediatric patients already admitted for orbital complications of acute rhinosinusitis was 0% for those less than 7 years of age and 9.3% (4/43) for patients 7 years and older. If surgery was required for orbital disease, these risks were 0 and 24% (4/17), respectively. The review found that patients with dual complications had a mean age of 15 years, 11 months, were male (100%), had subperiosteal abscesses located superiorly or superolaterally within the orbit, and presented with significant frontal sinus disease. All intraoperative cultures were polymicrobial. MRI was superior to CT for identification of intracranial extension. CONCLUSIONS: Simultaneous intracranial and orbital complications are rare but significant occurrences in acute pediatric rhinosinusitis. Because of the high incidence of intracranial findings, we recommend MRI in addition to CT scan along with aggressive management in children older than 7 years of age admitted with orbital complications of acute rhinosinusitis who also demonstrate risk factors for intracranial disease. These risk factors are discussed.

Abscess↗