Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “Orbit”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 955 records · Page 53Linked to original sources
PubMed2006

Free rectus abdominis myocutaneous flap with anterior rectus sheath to provide the orbital support in globe-sparing total maxillectomy.

Reconstruction after total maxillectomy with preservation of the orbital contents is technically more challenging than when the maxillectomy is combined with orbital exenteration. It results in severe complications if the orbital content is not supported. We would like to introduce a new technique using free rectus abdominis myocutaneous (RAM) flap with anterior rectus sheath to support the orbital content in a patient who underwent globe-sparing total maxillectomy. The large resection of the recurrent maxillary peripheral nerve sheath tumor was performed in a 34-year-old male patient. Right free RAM flap was harvested simultaneously with the tumor resection. The anterior sheath of upper portion of the rectus muscle was also incorporated into the flap. The free edge of the upper anterior rectus sheath was anchored to three different points: Lateral rim, medial rim and the posterior remnant of the bony orbital floor with non-absorbable suture. Consequently, orbital support was achieved with well-vascularized, thin, strong fascia with smooth surface. Right facial artery and vein were chosen as recipient vessel. Duration of the operation was 5.5 hours. Postoperative period was uneventful. Six months after the surgery, the right eye was in good position without inferior dystopia. Eyeball movement could be done without restriction. The patient also denied diplopia. Reconstruction of globe-sparing total maxillectomy defects with free RAM flap with anterior rectus sheath has several advantages that enable the reconstructive surgeon to solve the multiple complex reconstructive task with one flap: 1) elimination of the secondary donor site morbidity; 2) more simply addressing the challenging task of the eye support than the other techniques; 3) obliterating the maxillectomy defect and closing the palate; 4) restoring the large skin defect; and 5) reducing the operation time. It is difficult to conclude that this technique is the best choice in such cases based on a report of the single case. However, presented technique should be kept in mind as a practical and effective reconstructive option in cases that have underwent the total maxillectomy with the preservation of the orbit.

Adult↗
PubMed2006

Abscess of the orbit arising 48 h after root canal treatment of a maxillary first molar.

AIM: To discuss a rare, but severe complication arising following routine root canal treatment. SUMMARY: An orbital abscess is reported that occurred following routine root canal treatment. A young, healthy female patient, with no history of chronic paranasal infection had undergone root canal treatment of the right maxillary first molar. On hospital admission, she presented with extensive periorbital swelling and discreet diplopia. Computed tomography imaging identified massive purulent sinusitis and subsequent involvement of the orbit via the inferior and medial orbital wall within 48 h after completion of root canal treatment. Immediate surgical drainage of the maxillary sinus and the orbit was established and a high dose of perioperative antibiotics (Amoxicillin/Clavulanic acid, Gentamycin, Metronidazole) were administered. Vision remained undisturbed and mobility of the globe recovered within 10 days. KEY LEARNING POINTS: Rapid exacerbation of a periapical inflammation may occur following root canal treatment and may even involve the orbit. A typical speed of disease progression or ophthalmic symptoms should alert the clinician to at least consider unusual early orbital spread of odontogenic infection. When extra-alveolar spread and especially orbital spread is suspected, immediate referral to a maxillofacial or other specialized unit is mandatory.

Abscess↗
PubMed1997

Atypical choristomatous cysts of the orbit.

BACKGROUND: The commonset choristomatous cysts of the orbit are dermoid and epidermoid cysts, which are lined by kerantinizing squamous epithelium. They typically occur in the superior orbit, most commonly superotemporally. Other types, lined by different epithelia, and other orbital sites are much less common. METHODS: Five cases of atypical orbita cystic choristomas that presented over the past 6 years are reported. The clinical and radiological features, surgical approach and findings, and histology, are described. Similar cases from the literature are reviewed and possible aetiology discussed. RESULTS: Four of the cysts were lined by a non-keratinizing epithelium resembling conjunctiva; two had adnexal structures in their walls. Compared with typical dermoid and epidermoid cysts, these 'conjunctival dermoids' and 'conjunctival cysts' of the orbit tended to present later in life, none were associated with bony defects, and three of the four occurred in the superomedial quadrant. One case occurred inferiorly, a rare site for orbital conjunctival dermoids and cysts, or typical dermoids and epidermoids. The fifth case, also inferior, is an example of a cyst within choristomatous lacrimal tissue. CONCLUSION: Choristomatous cysts of the orbit may occur with non-keratinizing epithelial linings, and such cysts tend to differ clinically from the commoner dermoids and epidermoids. They may also occur in atypical sites such as the inferior orbit.

Adult↗
PubMed2004

Orbital development in Hong Kong Chinese subjects.

The purpose of this study was to examine the development of the orbit in Hong Kong Chinese subjects. Orbit volume was determined from magnetic resonance images of 81 subjects aged from 1 to 42 years old. Results show that orbit volume ranged from 11.56 to 25.50 cm3. In the first year of life, the mean orbit volume was 12.36 cm3. The orbit showed rapid growth in the first 3 years of life. From about 1-3 years old, the mean volume was 15.31 cm3. The orbit grew steadily to the age of 10 years. From age 11 to 15 years old, the mean volume was 20.24 cm3. Orbit growth levelled off at about 16 years of age with the mean volume at 21.00 cm3.

Adolescent↗
PubMed1997

Orbital metastases: diagnosis and course.

AIMS: Three issues were investigated in adult outpatients with orbital metastases. One, how accurate are current diagnostic methods? Two, what is the survival associated with orbital metastases? Three, did any clinical factors correlate with prognosis in this patient cohort? METHODS: Retrospective analysis of patients with orbital metastases managed in an ocular oncology unit. RESULTS: 11 of 31 (35%) patients had no known primary malignancy at the time of orbital diagnosis. In eight of 31 (26%) computed tomography and/or magnetic resonance imaging data did not yield the diagnosis of metastases. In 15 of 17 (88%) cases a fine needle aspiration biopsy was diagnostic. Several types of therapy were used. The median survival was 1.3 years. CONCLUSION: Orbital metastases, even with newer diagnostic techniques can be difficult to diagnose. Management was based on location and extent of both orbital and systemic disease as well as vision. In most cases, orbital symptoms were palliated; however, survival was dismal. No clinical factor correlated with prognosis.

Adult↗
PubMed2006

Myoneural junctions of extraocular muscles: distances from the orbital rim and widths.

PURPOSE: To examine both the distances from the orbital rim to the myoneural junctions (MNJs) and the widths of the MNJs of all extraocular muscles. METHODS: Six orbits of 3 post-mortem cadavers were used. The cadavers (1 female and 2 males) were all Japanese with an average age of 76.3 years. The MNJs of the extraocular muscles and their motor nerves were exposed, and then the distance from the orbital rim to each MNJ and the width of each MNJ were examined. RESULTS: The distance from the orbital rim to each MNJ in the 6 extraocular muscles ranged from 24.4 to 33.6 mm and the width of each MNJ ranged from 5.0 to 8.5 mm. CONCLUSIONS: It is essential for orbital surgeons to understand both the distance from the orbital rim to MNJs and the widths of MNJs. This information not only aids the understanding of MNJ damage, but also prevents iatrogenic nerve impairment during orbital surgery.

Aged↗
PubMed2005

Autologous T-lymphocytes stimulate proliferation of orbital fibroblasts derived from patients with Graves' ophthalmopathy.

PURPOSE: Graves' ophthalmopathy (GO) affects 50% to 60% of patients with Graves' hyperthyroidism, resulting in exophthalmos, periorbital edema, pain, double vision, optic neuropathy, and loss of vision. Fibroblasts are a key autoimmune target in GO and have effector functions that contribute to GO-associated pathologic conditions, including proliferation, production of excess glycosaminoglycans, and fat deposition. GO is also characterized by autoimmune inflammation of orbital connective tissue with mononuclear cell infiltration, including T cells. METHODS: To determine whether autologous T cells can drive proliferation of orbital fibroblasts and thus contribute to GO, a novel reverse autologous mixed-cell reaction (rAMCR) was performed. Fibroblasts cultured from orbital tissue of patients with GO that was removed during orbital decompression surgery were mixed with autologous T cells, and fibroblast proliferation was determined. RESULTS: Autologous T cells stimulated proliferation of orbital fibroblasts. Fibroblasts derived from blepharoplasty fat of two different patients did not proliferate, demonstrating that the effect is specific to cells derived from deep orbital fat. Proliferation was dependent on cell contact and on major histocompatibility complex (MHC) class II and CD40-CD154 (CD40 ligand) signaling. CONCLUSIONS: The results suggest that T cells and orbital fibroblasts participate in an antigen-dependent positive feedback loop in which presentation of autoantigens by fibroblasts via MHC class II and CD40-CD40L signaling results in T-cell activation. These activated T cells stimulate fibroblast proliferation, leading to fibroblast-associated diseases in GO. Thus, therapies that interfere with CD40-CD40L signaling, antigen expression by fibroblasts, or T-cell function may be effective in preventing progression of GO symptoms.

Antigen Presentation↗
PubMedDate not supplied

Computerized axial tomography in inflammatory pseudotumor of the orbit.

Although thyrotoxicosis and orbital complications of acute ethmoid or frontal sinusitis are among the most common causes of unilateral exophthalmos, inflammatory pseudotumor is frequently accompanied by progressive acute unilateral proptosis. Because the associated chemosis, scleral erythema, and ophthalmoplegia constitute a spectrum of clinical findings present in numerous inflammatory orbital disorders and systemic diseases, the diagnosis of inflammatory pseudotumor is one of exclusion, often requiring orbital biopsy. Four patients without evidence of sinusitis, endocrinopathy, collagen vascular disease, or Wegener's granulomatosis are described. The diagnosis of orbital pseudotumor was disclosed by computed axial tomography, thus avoiding orbitotomy. The finding of scleral and choroidal thickening with enhancement following intravenous contrast injection represents a select group of patients with orbital pseudotumor and differentiates them from patients with endocrine exophthalmopathy or neoplasms. This noninvasive technique is extremely valuable because early diagnosis is critical for successful treatment. All four patients responded dramatically to high-dose corticosteroid therapy. In the absence of significant clinical response, however, Wegener's granulomatosis, lymphoma, and rhabdomyosarcoma, especially in younger patients, must be carefully excluded. Orbital exploration or decompression or both are used when proptosis, headache, or orbital pain does not resolve promptly, visual acuity deteriorates, or the diagnosis remains unknown.

Adolescent↗
PubMed1991

Intraocular and orbital malignant schwannomas in F344 rats.

Intraocular and orbital malignant Schwannomas in two F344 rats are presented. The two Schwannomas were identified among approximately 60,000 male and 60,000 female F344 rats. The intraocular malignant Schwannoma occurred in the iris, invading the corneal stroma through the destroyed Descemet membrane. The malignant orbital Schwannoma occurred in the left orbit, invading the contralateral orbit along the optic nerve. Histologically, the intraocular Schwannoma consisted predominantly of a perivascular fascicular pattern of plump spindle cells associated with marked cytoplasmic vacuolization. The orbital Schwannoma consisted of Antoni type A and B pattern, but Antoni B tissues predominated. Antoni A tissues consisted of closely packed, elongated spindle cells arranged in interlacing fascicles, while Antoni B tissues were highly cellular and consisted of anaplastic, small cells associated with marked cyst formation. Immunohistochemically, the intraocular Schwannoma had a positive immunoreactivity for S-100 protein, while the orbital Schwannoma had a negative immunoreactivity. Ultrastructurally, the cells of both intraocular and orbital Schwannomas had long, thin cell processes and pericytoplasmic basal laminae. Particularly, the plump spindle cells of the intraocular Schwannoma were most strikingly characterized by the well developed, extremely attenuated cell processes arranged in a lamellar or spiral pattern. These cell processes and cell bodies were associated with numerous desmosomes. Intracytoplasmic filamentous granules and bodies, consisting of intermediate filaments approximately 7 nm in width, were additional characteristics of the plump spindle cells.

Animals↗
PubMedDate not supplied

Orbital emphysema and diplopia following thoracotomy.

PURPOSE: To describe the clinical and radiological findings in a patient with diplopia and orbital emphysema following thoracotomy. METHODS: Reported is a 71-year-old woman who presented with diplopia several days following thoracotomy. RESULTS: Physical examination revealed diffuse subcutaneous emphysema and a right hypertropia. Head computed tomography revealed facial and palpebral subcutaneous emphysema extending into the infratemporal fossa and orbits bilaterally. A chest tube was replaced and her diplopia resolved. CONCLUSIONS: Subcutaneous emphysema can lead to diplopia and orbital emphysema in the absence of orbital trauma. Contrary to previously suggested mechanisms of orbital emphysema associated with subcutaneous emphysema, computed tomography imaging suggested that air entry into the orbit in this case was through the inferior orbital fissure.

Aged↗
PubMed2002

Stimulation of adipogenesis, peroxisome proliferator-activated receptor-gamma (PPARgamma), and thyrotropin receptor by PPARgamma agonist in human orbital preadipocyte fibroblasts.

The symptoms and signs of Graves' ophthalmopathy (GO) result from both an accumulation of hydrated hyaluronan in the orbital muscles and connective tissues and an expansion of the orbital adipose tissues. Recent studies have suggested a link between the stimulation of adipogenesis within the orbit in GO and the expression in these tissues of TSH receptor (TSHR), the putative orbital autoantigen. To further investigate this association, we treated orbital fibroblasts from patients with GO with rosiglitazone, a thiazolidinedione agonist of the PPARgamma receptor that stimulates adipocyte differentiation. We found this compound to be a potent stimulator of functional TSHR expression as well as TSHR and PPARgamma mRNA levels in differentiated cultures. In addition, rosiglitazone treatment stimulated recruitment and differentiation of a subset of cells within these cultures into mature lipid-laden adipocytes. These results suggest that TSHR expression in GO orbital preadipocyte fibroblasts is linked to adipogenesis, and that ligation of the PPARgamma receptor results in differentiation of these cells. It is possible that endogenous PPARgamma ligands play a role in stimulating orbital adipogenesis in GO, and that future treatments may be aimed at antagonism of various components of the PPARgamma signaling system.

Adipocytes↗
PubMed2005

MacCarty keyhole and inferior orbital fissure in orbitozygomatic craniotomy.

OBJECTIVE: This study had two objectives. The first was to define the ideal position of the MacCarty keyhole, a commonly used craniotomy entry site into which three of the bone cuts in orbitozygomatic craniotomy extend. The second objective was to examine the relationships in the inferior orbital fissure, a site into which two of the bone cuts in orbitozygomatic craniotomy extend. METHODS: Twenty frontotemporal regions from adult skulls were examined to delineate the relationships between the surface anatomy of the fronto-orbitozygomatic region and the underlying frontal fossa and orbit. Drill holes placed along, above, and below the frontosphenoid suture were made beginning anteriorly at an area referred to as the three-suture junction, located at the junction of the frontozygomatic, sphenozygomatic, and frontosphenoid sutures. The site of the deep end of each hole was recorded to clarify the ideal position of the keyhole. The relationships in the inferior orbital fissure, the site of the lower end of the bone cut that begins in the orbital portion of the keyhole and extends along the lateral orbital wall, were also examined. CONCLUSION: Placing the MacCarty keyhole on the frontosphenoid suture 5 to 6 mm behind the three-suture junction results in greater preservation of the lateral wall and roof of the orbit than when the hole is placed at a more anterior site, as previously recommended. The anterolateral part of the inferior orbital fissure, which faces the temporal fossa and into which the bone cuts in the orbitozygomatic craniotomy extend, has a lower density of vascular and neural structures than the middle and posteromedial parts, which are related to the infratemporal and pterygopalatine fossa.

Cadaver↗
PubMed1998

Orbital sinus blood sampling in rats as performed by different animal technicians: the influence of technique and expertise.

In this study the influence of orbital sinus blood sampling on clinical signs was studied within the framework of various nutritional experiments. In order to assess the clinical signs in a random design, the rats were punctured in either the left or the right orbit. Thus, the effect of puncture within rats could be determined by comparing the left and right eye. Four animal technicians punctured a total of 303 rats, using different techniques. Orbital sinus blood sampling caused clinically visible alterations. The type, frequency and prognosis of the alterations differed with the person performing the puncture. Two experienced animal technicians were able to perform the technique without causing a statistically significant increase in alterations in punctured orbits. One less experienced animal technician caused severe abnormalities. The use of either a Pasteur pipette or a haematocrit capillary did not necessarily produce different results. Neither did puncturing the lateral vs the medial canthus of the orbit. By not applying chloramphenicol eye ointment in the conjunctival sac after puncture, the number of abnormalities in 'ocular discharge' and 'corneal alterations' in the punctured orbits was significantly decreased. Four punctures in the same orbit with 14-day intervals by a skilled animal technician did not cause a significant increase in abnormalities.

Animals↗
PubMedDate not supplied

[Surgical treatment of post-contusion orbital hematoma in the late phase].

OBJECTIVE: The object of the study was to present successfully performed decompression of the orbit in orbital hematoma. MATERIAL AND METHODS: Male, 51 years of age sustained the contusion injury of the right eye during his fall on the bath tap. It caused the development of a large orbital hematoma with protrusion, restricted movement of the eyeball, pain, diplopia, folding of the retina due to hemtoma compression to bulbus oculi and retinal hemorrhages, higher intraocular pressure and impaired visual acuity to 2/60. He was treated by medicaments for a month, but the results were not favorable. After one month from the injury, anterior-inferior transcutaneous orbitotomy was performed. During the surgical intervention, hematoma and a part of orbital fat tissue were removed. RESULTS: The globe of the eye was retracted and the exophthalmos disappeared immediately after the surgery, while the mobility of the eyeball, disappearance of retinal folds with gradual receding of hemorrhage, normal intraocular pressure, abatement of pain and diplopia as well as the restoration of visual acuity to normal ensued in a few subsequent days. CONCLUSION: This study illustrated that decompression of the orbit in orbital hematoma might be successful even in the late phase, e.g., one month following the injury. It is assumed that surgical intervention would be performed by experienced orbital surgeon.

Contusions↗
PubMed2006

Recognition and management of an orbital blowout fracture in an amateur boxer.

STUDY DESIGN: Case report. OBJECTIVES: To identify key elements in the recognition and management of a patient with an orbital blowout fracture and make recommendations on diagnosis, treatment, referral, imaging, and return to sports. BACKGROUND: Orbital blowout fractures are uncommon but important injuries for physical therapists to recognize. Immediate management is essential in preventing complications. The mechanism of injury is a direct blow to the orbital rim or orbit. CASE DESCRIPTION: The patient reported to the athletic training room 15 minutes after completing a boxing match and reported that his left eye had suddenly inflated after blowing his nose. We suspected an orbital blowout fracture and referred him immediately to the emergency department where conventional radiographs were ordered. On follow-up the next day, after determining that the radiographs were normal, but still having a high index of suspicion for an orbital blowout fracture, we referred him to his primary care manager. The primary care manager ordered a computed tomography scan that revealed the fracture and referred the patient to ophthalmology. OUTCOMES: The patient was restricted from the remaining 4 weeks of the boxing season. He completed a rigorous Army physical fitness test 7 days postinjury and the Marine Corps Marathon 47 days postinjury. DISCUSSION: Orbital blowout fractures without double vision, extraocular muscle entrapment, or persistent numbness can be treated with time and protection. The patient can continue with normal fitness activities except contact or collision sports.

Adult↗
PubMed2004

Immunohistochemical determination of the sympathetic pathway in the orbit via the cranial nerves in humans.

OBJECT: The present study was undertaken to elucidate the extent and precise distribution of the postganglionic sympathetic fibers in the cranial nerves projecting to the orbit and to reconstruct sympathetic routes in the orbit in humans. For this purpose, the authors made an immunohistochemical determination of the sympathetic fibers by using an antibody against norepinephrine-synthetic enzyme, tyrosine hydroxylase (TH). METHODS: Specimens containing the orbit and the cavernous sinus were obtained from formalin-fixed human cadavers. First, it was confirmed that the superior cervical ganglion contained strongly immunostained TH-positive neuronal cell bodies and fibers. After careful dissection of the cranial nerves projecting to the orbit, different segments of each cranial nerve were processed for immunohistochemical analysis for TH. All of the intraorbital cranial nerves contained TH-positive sympathetic fibers, although the amounts were very different in each cranial nerve. At the proximal site of the common tendinous ring, TH-positive fibers were found mainly in the abducent and trochlear nerves. At the distal site of this ring, TH-positive fibers were lost or markedly reduced in number in the abducent and trochlear nerves and were distributed mostly in the ophthalmic and oculomotor nerves. Among the cranial nerves projecting to the orbit, the ophthalmic nerve and its bifurcated nerves--frontal, lacrimal, and nasociliary--contained numerous TH-positive fibers. CONCLUSIONS: The authors conclude that the postganglionic sympathetic fibers are distributed to all cranial nerves projecting to the orbit and that the ophthalmic nerve provides a major sympathetic route in the orbital cavity in humans.

Abducens Nerve↗
PubMed2000

Two cases of orbital infarction syndrome.

Orbital infarction syndrome is defined as ischemia of all intraorbital and intraocular structures. It is a rare disease caused by rich anastomotic vascularization of the orbit. It can occur secondary to different conditions, such as, acute perfusion failure, systemic vasculitis, orbital cellulitis and vasculitis. It results in orbital and ocular pain, total ophthalmoplegia, anterior and posterior segment ischemia, and acute blindness. We report here upon two cases of orbital infarction with similar presentations but with different causes, namely, mucormycosis and as a postoperative complication of intracranial aneurysm, discuss the possible mechanisms of orbital infarction, and present a review of the literature on the topic. The prompt recognition of clinical pictures and rapid diagnosis is essential for the early treatment of orbital infarction, since its progression is very rapid and it can be even fatal.

Adult↗
PubMed2001

Orbital exenterations and squamous cell carcinoma of the conjunctiva at Sekuru Kaguvi Eye Unit, Zimbabwe.

OBJECTIVES: The aim of the audit was to determine the common orbital diseases necessitating orbital exenterations at Sekuru Kaguvi Hospital (SKH) between January and December 1999 and recommend ways of reducing the numbers of procedures done annually. DESIGN: Retrospective cross sectional study. SETTING: Department of Surgery, Parirenyatwa Hospital, University of Zimbabwe. SUBJECTS: 23 patients who underwent orbital exenterations at SKH over a one year period. MAIN OUTCOME MEASURE: The nature of orbital tumours requiring orbital exenteration in Zimbabwe. RESULTS: A total of 23 patients underwent orbital exenteration during the period under review. Of the 23 patients, 13 (56.5%) had squamous cell carcinoma (SCCA) of the conjunctiva with orbital extensions, 69% of the 13 patients were females and the mean age of these patients was 37.2 years (interquartile range 28, 48). CONCLUSIONS: People in tropical regions, where there is a high risk of squamous cell carcinoma of the conjunctiva in terms of increased predisposition to solar radiation, high prevalence of HIV and inadequate eye care services, should seek medical attention as soon as they notice a persistent conjunctival growth. Conjunctival tumours should be widely excised and material sent for histology to confirm diagnosis and clarity of excision margins. All patients diagnosed as having SCCA of the conjunctiva should be closely monitored to facilitate early detection of recurrences and institute appropriate treatment.

Adult↗