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At least 163 records · Page 9Linked to original sources

PubMed2006

Orbital pseudotumour presenting as orbital cellulitis.

A 33-year-old woman presented to a community emergency department with a 4-day history of monocular orbital pain, photophobia and pain on extraocular movement. Findings included chemosis, conjunctival injection and restricted extraocular movements causing strabismus. She was diagnosed with orbital cellulitis during her initial emergency department visit and treated with intravenous antibiotics. On her second ED visit later the same day, a diagnosis of orbital pseudotumour was made after computed tomography revealed inflammation of the sclera, optic nerve, muscle and adipose tissue within the orbit. Antibiotics were discontinued and tapering steroids were initiated, with prompt resolution of symptoms.

Adrenal Cortex Hormones↗

PubMed2006

Rehabilitation of orbital cavity after total orbital exenteration using oculofacial prostheses anchored by osseointegrated dental implants posed as a one-step surgical procedure.

BACKGROUND: Total orbital exenteration is a radical surgical procedure, which typically involves the removal of the entire contents of the orbit including the periorbita, leaving the patient with a deep orbital deformity and results in devastating cosmetic, functional, and psychological consequences requiring difficult and challenging procedures for oculoplastic surgeons. Oculofacial prostheses retained by endosseous dental implants present an attractive and viable alternative when aesthetic and functional demands are beyond the capacity of local reconstructive efforts. PATIENTS AND METHODS: A 72-year-old woman presenting a malignant melanoma of the right eyelids and a 77-year-old man presenting a sebaceous carcinoma of the left upper eyelid underwent a total exenteration followed by positioning of endosseous implants (Straumann system Dental implants) as an integrated one-step combined surgical procedure. The oculofacial prosthesis was placed after epithelialization of the orbital cavity. RESULTS: The implants were perfectly osseointegrated without any complications, providing sufficient retention of the prostheses. A satisfactory aesthetic outcome has been achieved for both patients. CONCLUSIONS: Oculofacial prostheses anchored by osseointegrated dental implants placed as one-step surgical procedure ensure an adequate aesthetic result as well as a considerably decreased rehabilitation time and present a satisfactory solution when reconstruction is not a suitable option.

Dental Implants↗

PubMed1990

The transconjunctival approach to the orbital floor and orbital fat. A prospective study.

The transconjunctival approach to the inferior orbit and orbital fat offers the potential advantage of avoidance of scar creation in the lower eyelid skin and anterior lamellae. Complications of this approach, including conjunctival fornix shortening and eyelid margin malposition, have been occasionally reported. We prospectively observed 25 patients undergoing transconjunctival blepharoplasty and orbital floor surgery. Fornix depth, eyelid margin position, and the presence or absence of eyelid retraction were measured preoperatively and at each postoperative visit. No significant permanent change in these parameters was observed. Temporary entropion was observed in two patients; this resolved with conservative treatment. On self-limited suture granuloma was observed. In a subgroup of six patients, the conjunctival incision was closed on one side and left unclosed on the other. No adverse healing was noted on the unclosed side. We conclude that the transconjunctival approach is associated with a low incidence of complications, and that it does not significantly alter the fornix depth or eyelid margin position. A skin incision is avoided. The inferior orbital septum is not violated, greatly reducing the risk of development of lower eyelid retraction.

Adipose Tissue↗

PubMed1996

Differential expression of immunoreactive HLA-DR and ICAM-1 in human cultured orbital fibroblasts and orbital tissue.

Intercellular adhesion molecule-1 (ICAM-1) and class II major histocompatibility complex antigens (MHC II, HLA-DR), are two cell-surface ligands known to be critical to the initiation and propagation of immune-mediated inflammation. Their expression in tissue is induced by proinflammatory mediators, principally interferon-gamma, tumor necrosis factor-alpha, and interleukin-1 beta. We examined human orbital fibroblasts and intact human orbital tissue exposed to these mediators for the presence of immunoreactive ICAM-1 and HLA-DR antigen. These ligands were detectable on stimulated fibroblasts and on fibroblasts and vascular endothelium in samples of orbital fat and muscle. ICAM-1 reactivity was diffuse and occurred in response to all three proinflammatory mediators. In contrast, HLA-DR reactivity was intense but limited to fewer numbers of cells. Our results, demonstrating the differential expression of these two ligands, may help further to elucidate the underlying pathogenetic mechanisms involved in the initiation and perpetuation of immune-mediated orbital inflammatory diseases.

Adipose Tissue↗

PubMed1996

Late migration of an orbital implant causing orbital hemorrhage with sudden proptosis and diplopia.

A 31-year-old woman complained of sudden diplopia and proptosis associated with a headache. Approximately 10 years earlier, she had sustained a right orbital blowout fracture during a snow machine accident that was repaired using a Supramid implant. She presented with 4 mm of right-sided proptosis by Hertel exophthalmometry, with limitation of up and down gaze. She manifested a right gaze preference with a left head turn to achieve fusion. Visual acuity was 20/20 on both sides; however, there was 20% red desaturation and a subtle afferent pupillary defect on the right side. Goldmann visual fields were full and the retinal examination was normal. A computed tomography (CT) scan of the orbits with and without contrast demonstrated a large right posterior inferior orbital mass. Once the periorbita was breached during orbitotomy, a burgundy serosanguinous material emerged. Gram staining revealed red cells without organisms. The implant had not been fixed by wires or screws. Upon removal, the implant appeared oversized, encompassing the orbital floor, medial and lateral walls. Postoperatively, the proptosis, gaze preference with face turn, afferent pupillary defect, desaturation abnormality, and diplopia resolved.

Adult↗

PubMed2000

Orbital Ewing's sarcoma of the orbit.

PURPOSE: Ewing's tumor is a primary tumor of bone in childhood that only rarely involves the orbit. Most such cases are metastatic from distant sites. This tumor may be confused with other small round cell malignancies of childhood, and immunohistochemical studies are essential in making the diagnosis. METHODS: We present two cases of Ewing's tumor of the orbit. One was in a 22-year-old boy with an occult primary tumor in the frontal bone that became symptomatic after forehead trauma. The other example was in a 7-year-old boy with a known Ewing's primary of the clavicle. The clinical manifestations and diagnostic criteria are discussed. RESULTS: In most cases with orbital involvement, ophthalmic symptoms consist of proptosis, pain, and occasionally visual loss and motility restriction. The diagnosis is typically unsuspected before histologic evaluation. Electron microscopic and immunohistochemical analyses are essential in making the diagnosis and are necessary for all such small round cell tumors. CONCLUSIONS: Ewing's sarcoma is a rare orbital tumor of bone mainly affecting children. Local treatment relying on surgical extirpation and radiotherapy alone has proven inadequate, with 5-year survival rates of <10%. The addition of chemotherapy has improved survival rates significantly to approximately 50%.

Biopsy↗

PubMed2004

Mega dose corticosteroid treatment for traumatic superior orbital fissure and orbital apex syndromes.

The superior orbital fissure syndrome and orbital apex syndrome are rare complications of craniomaxillofacial traumas. The neurologic symptoms are generally due to reversible neuropathy caused by edema, contusion, and compression of the nerves. Much has been written but no firm conclusions have been reached on the best mode of treatment. Whereas some authors advocate emergency optic nerve decompression, others recommend mega dose corticosteroids alone. We have treated 11 patients with traumatic superior orbital fissure or orbital apex syndromes with mega dose corticosteroids in the last 10 years. No complications attributable to the very high dose of corticosteroids were observed. The long-term follow-up of the patients showed complete recovery. These satisfactory results have led to our recommendation of the mega dose corticosteroid treatment in the management of these patients.

Adult↗

PubMed1988

Ethmoid osteoma, orbital cellulitis and orbital emphysema.

A possibly unique association of an osteoma of the ethmoid sinus with orbital emphysema and orbital cellulitis is described. The osteoma, which had eroded through the orbital periosteum, was removed; the orbital periosteum was grafted with fascia lata and a partial external ethmoidectomy performed.

Adolescent↗

PubMed2001

Detection of sinus-induced orbital mycosis with standardized orbital ultrasonography: a case report.

Fungal involvement of the paranasal sinuses is frequently observed in the immunocompromised host, and it can become life-threatening if it is not diagnosed. Although the definitive diagnosis is made by tissue biopsy and culture, imaging is of vital importance in the clinical workup and in planning treatment. We present a case of fulminant ethmoidal sinusitis caused by Aspergillus flavus with orbital involvement in an immunocompromised patient. Standard computed tomography of the paranasal sinuses was complemented by the use of standardized orbital ultrasonography, which was able to identify the intraorbital extension. We discuss the role of standardized orbital ultrasonography as a complementary imaging modality in the diagnosis of fungal sinusitis and in the assessment of local extension. To the best of our knowledge, the role of SOU in diagnosing an orbital extension of a fungal infection of the paranasal sinuses has not been previously discussed in the literature.

Aged↗

PubMed2004

Causes and effects of zygomatico-orbital and zygomatico-maxillo-orbital fractures managed by open reduction and rigid internal fixation.

Progressive violence, the quickening pace of life and transport facilities' development have as a consequence an increased number of traumas. Midface fractures involving zygomatic bone fractures take one of the leading positions in the total number of traumas. It seems appropriate to study the causes and the effects of zygomatico-orbital and zygomatico-maxillo-orbital fractures managed by open reduction and rigid internal fixation at the present time of the medical service being reformed and economic rules being included in the treatment. The analysis of the economic consequences of midface traumas and their causes as well as the search for the influence of social and cultural changes on fracture management was the aim of the study. Histories of 61 injured patients treated by open reduction and rigid internal fixation in 1st Department of Maxillofacial Surgery of the Silesian Medical University in Zabrze between 1996 and 2001 were studied. Patients' sex, the most frequent trauma causes and their disposition in different age groups were taken into consideration. It was observed that certain symptoms of the fracture tend to coexist with high energy traumas (traffic accidents, violent assaults). The influence of injury's extension on the prolongation of hospitalization time was emphasized. It was concluded that assaults and traffic accidents are the most frequent and devastating causes of zygomatico-orbital and zygomatico-maxillo-orbital fractures. The fractures usually involve men aged from 21 to 40 years. The rapid growth of violence and the pace of life have in recent times necessitated the general use of advanced and expensive operating techniques in injured patients recently. The break in social and professional activity of injured individuals and the scale of the problem indicate the necessity of change in medical service financing.

Adolescent↗

PubMed1988

Orbitotonography, the dynamic assessment of orbital tension: 2. Results in patients with orbital disease.

Dynamic orbitotonography was done in 17 patients with Graves' disease, 25 patients with orbital tumours and 15 healthy subjects. The mean orbital pressure for both patient groups was significantly different from that for the healthy subjects at each time interval (p less than 0.001). Healthy patients may be differentiated from those with orbital disease with a good degree of reliability with this technique. As well, the technique may provide information about the location of disease within the orbit.

Adult↗

PubMed1982

Bony interorbital distance (BIOD), head size, and level of the cribriform plate relative to orbital height: II. Possible pathogenesis of orbital hypertelorism.

This investigation was designed to test hypothesized pathogenetic mechanisms for orbital hypertelorism (OrH). Serial measurements of bony interorbital distance (BIOD), level of cribriform plate relative to orbital height (LOCP), and cranial width (CW) were made from postero-anterior cephalometric radiographs on two pathologic groups craniofacial clefts (FC) and premature craniofacial synostosis syndromes (PCS) compared with normal controls matched for age and sex. Both groups of malformations showed significantly larger mean values (P less than 0.01) for BIOD alone and when adjusted for CW. The LOCP relative to the orbital height was found to be positioned at a significantly lower level (P less than 0.01) than the norm in both groups. When the growth increments for BIOD were plotted to analyze rates of growth, individuals with FC showed increments similar to those seen for the normal. However, patients with Apert and Crouzon syndromes showed greater than normal increments for BIOD. In these cases, the LOCP remained at a relatively lower level in relation to orbital height. These findings support the hypothesis of a time-specific event during fetal development causing morphokinetic arrest in FC syndromes. In Apert and Crouzon, another mechanism continuing postnatally produces OrH.

Adolescent↗

PubMed2005

Optimal virtual orbitals to relax wave functions built up with transferred extremely localized molecular orbitals.

Extremely localized molecular orbitals (ELMOs), namely orbitals strictly localized on molecular fragments, are easily transferable from one molecule to another one. Hence, they provide a natural way to set up the electronic structure of large molecules using a data base of orbitals obtained from model molecules. However, this procedure obviously increases the energy with respect to a traditional MO calculation. To gain accuracy, it is important to introduce a partial electron delocalization. This can be carried out by defining proper optimal virtual orbitals that supply an efficient set for nonorthogonal configurations to be employed in VB-like expansions.

Journal Article↗

PubMed1996

Effects of orbit progression on the radiation exposures from solar proton fluxes in low Earth orbit under geomagnetic storm conditions.

The present study examines the effects of orbit progression on the exposures within a Space Station Freedom module in a 51.6-degree inclined orbit at 450 km. The storm evolution is modeled after the November 1960 event, and the solar proton flux evolution is taken from the August 1972 solar proton event. The effects of a strong magnetic shock, such as was observed during the October 1989 event, is also modeled. The statistics on hourly average storm fields for the last forty years reveal that the largest geomagnetic storms approach a Dst value of -500 nanotesla at the storm peak. Similarly, one of the largest satellite-measured proton flux (> 10 MeV) for space exposures is the event of August 1972. The effects of orbit progression (advance of the line of nodes) is examined for the above conditions to study the variation of exposures under differing times of occurrence of the solar proton peak intensity, attainment of geomagnetic storm maximum, and the location of the line of nodes of the last geomagnetically protected orbit. The impact of the inherent inhomogeneity of the space station module is examined as a limiting factor on exposure with regard to the need of additional parasitic shielding.

Algorithms↗

PubMed1976

Correlation of nonorthogonality of best hybrid bond orbitals with bond strength of orthogonal orbitals.

An expression is derived for the bond length of two spd orbitals with maximum values in two directions forming a given bond angle by consideration of the nonorthogonality integral of two best orbitals in these directions. This equation is equivalent to the expression derived by formulating the pair of orthogonal orbitals. Similar expressions are derived for spdf orbitals. Applications are made to icosahedral and cuboctahedral bonds and to the packing of nucleons in atomic nuclei.

Journal Article↗

PubMed1991

The acute orbit: differentiation of orbital cellulitis from subperiosteal abscess by computerized tomography.

A series of 65 patients suffering from acute inflammatory disease of the orbit was studied by CT. Ethmoiditis was the cause in the vast majority; trauma and dental extraction played a lesser role in causation. Orbital cellulitis was diagnosed in 17 and subperiosteal abscess in the remaining 48. It was not possible to differentiate 33 pus-containing abscesses from the six with inflammatory masses (phlegmons). The satisfactory response to aggressive medical treatment in those patients with inflammatory masses that were not drained justifies a more conservative approach; surgical drainage being reserved for those with a deterioration in proptosis, ocular movements or vision. Six abscesses arose de novo, of which some were in the orbital fat rather than the subperiosteal space.

Abscess↗

PubMed1995

The use of silastic as an orbital implant for reconstruction of orbital wall defects: review of 311 cases treated over 20 years.

PURPOSE: A retrospective review of silicone rubber (Silastic; Dow Corning, Midland, MI) implants placed in orbits was undertaken. These implants were used to reconstruct defects in the orbital floor and/or walls secondary to trauma, or those created during malar or orbital osteotomies. The purpose of the study was to determine the incidence of removal of these implants from the surgical site. MATERIALS AND METHODS: The records of 311 patients treated over a 20-year period were reviewed. Of these, 302 had received silastic implants secondary to trauma. RESULTS: Forty-one patients (13%) had their implant removed at a second operation. The reasons for removal included infection, migration of the implant, worsening eye sign such as diplopia, and others. CONCLUSION: Because there was a clinically significant rate of removal of this material, consideration should be given to the use of other available materials.

Adolescent↗

PubMed1996

Orbital emphysema and the medial orbital wall: a review of the literature with particular reference to that associated with indirect trauma and possible blindness.

Orbital emphysema is not an uncommon finding following fractures of the facial skeleton. Both its significance as a threat to sight and its diagnostic value may well be underestimated. Fractures of the paranasal sinuses may occur as a result of indirect trauma. This article reviews the literature on the subject with particular reference to blindness as a possible sequel. Two cases of orbital wall fracture that occurred as a result of indirect trauma and which produced orbital emphysema are discussed.

Adult↗