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PubMed1995

Orbital expansion of the congenitally anophthalmic socket.

BACKGROUND: Congenital anophthalmos is a rare condition in which intervention at an early age can stimulate orbital expansion and maximise facial symmetry. Much is still unknown, however, regarding the degree of soft tissue and bony orbital growth achieved using the orbital expanders presently available. METHODS: A retrospective review of 59 congenitally anophthalmic orbits in 42 patients was carried out. RESULTS: The soft tissue and bony orbital expansion achieved using serial solid shapes is reported, and experience with hydrophilic expanders and inflatable silicone expanders is reviewed. CONCLUSION: Although serially fitted solid shapes in the orbit lead to increased expansion of orbital soft tissue and bone compared with no orbital implant, further orbital tissue enlargement is required. The inflatable silicone expander may allow more rapid and extensive orbital tissue expansion, but design changes are needed to achieve this.

Anophthalmos↗

PubMed1995

Human orbital fibroblasts in culture express ganglioside profiles distinct from those in dermal fibroblasts.

Orbital fibroblasts appear phenotypically distinct from those derived from dermis and other extraorbital anatomical sites. In this study, we examined the profile of gangliosides expressed by orbital and dermal fibroblasts. Gangliosides have a wide range of functions including modulation of transmembrane signal transduction. The aim of this study was to examine the hypothesis that a differential expression of gangliosides by orbital and nonorbital fibroblasts could constitute an important determinant of the immunological properties peculiar to the orbit. Moreover, these differences could provide a molecular basis for the site-specific involvement of the orbit in Graves' ophthalmopathy. Total lipids were extracted from confluent cultures of six different orbital and six dermal fibroblast strains, and purified gangliosides were subjected to two-dimensional thin layer chromatographic analysis. Orbital and dermal fibroblasts contained qualitatively similar ganglioside contents, with two major peaks, one migrating in the mono- and the other in the disialoganglioside regions of the chromatogram. In orbital fibroblasts, the densities of these two peaks were nearly equal, whereas in dermal fibroblasts, the monosialoganglioside peak was 5- to 6-fold greater. Minor ganglioside peaks were resolved and were equally abundant in orbital and dermal fibroblasts. Ganglioside profiles were invariant with respect to treatment of fibroblasts with interferon-gamma. These differences in expression of the two major ganglioside species may be relevant to the peculiarities associated with normal and pathological events in orbital connective tissue.

Cells, Cultured↗

PubMed1985

Volume measurements of normal orbital structures by computed tomographic analysis.

Computed tomographic digital data and special off-line computer graphic analysis were used to measure volumes of normal orbital soft tissue, extraocular muscle, orbital fat, and total bony orbit in vivo in 29 patients (58 orbits). The upper limits of normal for adult bony orbit, soft tissue exclusive of the globe, orbital fat, and muscle are 30.1 cm3, 20.0 cm3, 14.4 cm3, and 6.5 cm3, respectively. There are small differences in men as a group compared with women but minimal difference between right and left orbits in the same person. The accuracy of the techniques was established at 7%-8% for these orbit structural volumes in physical phantoms and in simulated silicone orbit phantoms in dry skulls. Mean values and upper limits of normal for volumes were determined in adult orbital structures for future comparison with changes due to endocrine ophthalmopathy, trauma, and congenital deformity.

Adult↗

PubMed2002

Pneumosinus dilatans associated with orbital neurilemmoma.

BACKGROUND: [corrected] Pneumosinus dilatans (PSD) is a rare condition. It has been reported in association with spheno-orbital meningioma, optic nerve sheath meningioma, orbital fibro-osseous diseases and intracranial meningioma, but never with orbital neurilemmoma. We report 4 cases of orbital neurilemmomas in association with PSD, and stress the importance of PSD in cases of orbital neurilemmomas. METHODS: We reviewed the hospital chart, and found 324 orbital tumors were found from 1974 to 1996. Eight consecutive cases of pathology-proven primary orbital neurilemmoma were studied. Clinical features, es pecially computed tomography (CT) scan, were completely reviewed to find the co-existence of orbital neurilemmoma and pneumosinus dilatans. RESULTS: Four cases (50%) among 8 cases of pathology-proven orbital neurilemmomas were found to have pneumosinus dilatans in their CT scan. All these four cases were extraconal tumors. Representative CT scan showed enlarged, aerated sinus with thinning of the affected sinus walls. Ethmoidal, frontal and maxillary sinuses were the most frequently affected. CONCLUSIONS: Pneumosinus dilatans is commonly associated with primary orbital neurilemmoma.

Adult↗

PubMedDate not supplied

[Indications of exploration and repair of the orbital floor in fractures of the maxillozygomatic complex].

UNLABELLED: Patients with orbital fractures may develop late complications like enophthalmos, orbital dystopia or diplopia, as a result of untreated orbital floor lesions, with herniation of orbital fat. Clinical and radiological findings are not enough for diagnostic and indication of orbital floor repair. PURPOSE: To evaluate the indication of repair of the orbital floor, during the surgical treatment of maxillozygomatic or zygomatic-maxillary compound fractures, by means of systemic exploration and to compare clinical with surgical findings. METHODS: 112 patients with unilateral zygomatic-maxillary compound fracture were submitted to exploration of the orbital floor, during the surgical treatment of the fracture. Open reduction and rigid internal fixation was performed with steel wire or miniplates. An autogenous conchal cartilage graft was used to repair the floor lesion, when there was bone loss of the inferior orbital wall and periorbita discontinuity, with fat herniation. RESULTS: The repair of the orbital floor was indicated in 46.4% of the patients. Early diplopia (before surgery) was observed in 26.6% and enophthalmos in 3.30% of the cases. Among patients with early diplopia, 60% needed repair, while 36.6% of the patients without early diplopia received cartilage graft. No important complications was observed. CONCLUSION: Orbital floor exploration is a complementary maneuver for the treatment of zygomatic-maxillary compound fractures that permits the precise diagnostic of the lesion and the correct indication of repair.

Adult↗

PubMed2001

Reconstruction with rectus abdominis myocutaneous free flap after orbital exenteration in children.

OBJECTIVE: To present a 1-stage technique for orbital reconstruction after exenteration with the use of myocutaneous rectus abdominis free flap in children. SURGICAL TECHNIQUE: After orbital exenteration, a myocutaneous rectus abdominis free flap with long vascular pedicle is harvested from the abdomen. The flap is transferred to the orbit and the vascular pedicle is passed through an opening made in the lateral orbital wall, where it is anastomosed to superficial temporal vessels. The skin of the flap is trimmed to correspond to the eyelid defect and the incisions are closed. METHODS: After informed consent was obtained, 2 children, 3 and 8 years old, underwent orbital reconstruction with a rectus abdominis free flap after exenteration for orbital rhabdomyosarcoma and orbital osteosarcoma in the setting of retinoblastoma. RESULTS: This technique allowed easy postoperative wound care. Viability of the flap was excellent. The technique provided sufficient volume to fill the orbit, with improved aesthetic results and minimal donor site deformity. CONCLUSIONS: The postoperative care and aesthetic outcome in patients with rectus abdominis free flap after exenteration are much improved over those provided with traditional surgical techniques. This primary reconstruction is recommended for any patient requiring orbital exenteration, but particularly for pediatric patients who tolerate debridement of traditional exenteration sites poorly.

Child↗

PubMed1997

[Diagnosis and therapy of lymphoid tumors of the orbits].

For the evaluation of neoplastic orbital lesions an interdisciplinary concept is crucial and includes modern imaging techniques as well as rhinosurgical approaches to the orbit. During a 14-year period 6 primary malignant orbital lymphomas and 9 cases of orbital pseudotumors were managed at our department. In most of the cases an exophthalmus with painful swelling of the eyelids, diplopia and a loss of vision were the clinical symptoms. Imaging using CT or MRI revealed homogeneous tissue formations that could not be clearly demarcated from adjacent orbital structures. By a rhinosurgical approach a biopsy was performed of each lesion without surgical complications. Following diagnosis the localized malignant lymphomas of the orbit were irradiated. In one patient systemic spread of tumor required multi-drug chemotherapy. Two patients died as the result of the sequleae of disseminated plasmocytomas. Patients with orbital pseudotumors were treated with systemic steroids. Two patients were also irradiated. No malignant transformation of any orbital pseudotumor was observed in this series. Our experiences show that careful histological evaluation of lymphoid orbital masses is necessary for correct diagnosis, especially since this has great impact on treatment and prognosis. Depending on the localization of a lesion medial orbitotomy by a rhinosurgical approach has proven to be a safe method for performing a biopsy or extirpating tumor.

Adult↗

PubMed1997

Orbital venous anomalies.

PURPOSE: The purpose of the study is to establish the natural history, probable nature, and optimal treatment of lesions within the orbit described previously as lymphangiomas or orbital varices. METHODS: The clinical and radiologic records of 158 patients with these lesions were reviewed. Of these, 91 had surgery, and histologic specimens from 57 were re-examined. RESULTS: Most patients were infants or children with a dark blue swelling in the superomedial part of the orbit, orbital hemorrhage, or proptosis. Computed tomography showed smooth, contoured lesions denser than brain extending posteriorly. Half enlarged with the Valsalva maneuver, 31% contained phleboliths. Surgery was performed in 91 patients, mainly for cosmesis. Excised tissue included endothelium-lined channels containing blood in the orbit and clear fluid in many superficial specimens. CONCLUSIONS: The behavior of these lesions and their prevalence in infancy and childhood favor a hamartoma. The authors observed a seamless range of clinical features that they could not subdivide, particularly in relation to any connection with the orbital veins. Many bleed and enlarge permanently and need excision, but surgery is difficult and management should be as conservative as possible. The origin of these lesions cannot be determined by histopathologic analysis, although the authors have evidence of venous features in the orbit and lymphatic features more superficially. The authors' clinical findings support a venous origin. Two-thirds have either a free venous connection or phleboliths. Their distribution corresponds with that of the normal orbital veins, and at surgery they derive from or replace those veins. "Orbital venous anomaly" is the most accurate term for their description.

Adolescent↗

PubMed1990

Current status of magnetic resonance imaging of the orbit.

MR plays an important role in evaluating pathologic conditions that affect the orbit. MR appears to be superior to ultrasound and computed tomography in evaluation of intraocular tumors and fluid collections. In evaluation of noncalcified intraorbital tumors, MR can provide more information regarding orbital apex involvement and intracranial extension. Inflammatory lesions, particularly orbital pseudotumor, can be differentiated from metastatic disease based on differences in signal intensity providing greater specificity than CT. Specific prognostic information may be obtained regarding potentially treatable cases of Graves' disease. Using MR, vascular lesions of the orbit can be assessed for patency or thrombosis without use of intravenous contrast. Demonstration of secondary extension by para-orbital sinus tumors by MR is often helpful in evaluating involvement of the soft tissue structures of the orbit. Potential applications in evaluation of orbital trauma include characterization of orbital hematomas and orbital blow-out fractures.

Humans↗

PubMed1995

Management of the orbital contents in radical surgery for squamous cell carcinoma of the maxillary sinus.

We reviewed retrospectively 139 patients with squamous cell carcinoma of the maxillary sinus who were treated with planned combinations of preoperative radiotherapy and maxillectomy between 1958 and 1987. The 5-year survival rate of these patients was 30%. In 111 patients who had tumor invasion of the orbital floor 88 underwent radical surgery with orbital exenteration and 23 had their orbital contents preserved. If orbital exenteration was performed, the 5-year survival rate was 27.3% (24/88) and the rate of recurrence within the orbit was 12.5%. In patients with preservation of the orbital contents, the corresponding rates were 34.8% (8/23) and 8.6% respectively (P = 0.65). Histological study after maxillectomy with orbital exenteration showed that in 95% of 65 specimens (62/65) invasion of the orbit was limited. These tumors could be completely resected by total maxillectomy with limited removal of the periorbital tissues after preoperative radiotherapy. We conclude that after preoperative radiation, the eyeball could be safely preserved in most selected patients with maxillary sinus carcinoma invading the orbital floor.

Adult↗

PubMed1995

Limbic connections of the orbital and medial prefrontal cortex in macaque monkeys.

Previous studies have shown that the orbital and medial prefrontal cortex (OMPFC) is extensively connected with medial temporal and cingulate limbic structures. In this study, the organization of these projections was defined in relation to architectonic areas within the OMPFC. All of the limbic structures were substantially connected with the following posterior and medial orbital areas: the posteromedial, medial, intermediate, and lateral agranular insular areas (Iapm, Iam, Iai, and Ial, respectively) and areas 11m, 13a, 13b, 14c and 14r. In contrast, lateral orbital areas 12o, 12m, and 12l and medial wall areas 24a,b and 32 were primarily connected with the amygdala, the temporal pole, and the cingulate cortex. Data were not obtained on the posteroventral medial wall. Three distinct projections were recognized from the basal amygdaloid nucleus: 1) The dorsal part projected to area 12l; 2) the ventromedial part projected to most areas in the posterior and medial orbital cortex except for area Iai, 12o, 13a, and 14c; and 3) the ventrolateral part projected to orbital areas 12o, Iai, 13a, 14c, and to the medial wall areas. The accessory basal and lateral amygdaloid nuclei projected most strongly to areas in the posterior and medial orbital cortex. The medial, anterior cortical, and central amygdaloid nuclei and the periamygdaloid cortex were connected with the posterior orbital areas. The projection from the hippocampus originated from the rostral subiculum and terminated in the medial orbital areas. The same region was reciprocally connected with the anteromedial nucleus of the thalamus, which received input from the rostral subiculum. The parahippocampal cortical areas (including the temporal polar, entorhinal, perirhinal, and posterior parahippocampal cortices) were primarily connected with posterior and medial orbital areas, with some projections to the dorsal part of the medial wall. The rostral cingulate cortex sent fibers to the medial wall, to the medial orbital areas, and to lateral areas 12o, 12r, and Iai. The posterior cingulate gyrus, including the caudomedial lobule, was especially strongly connected with area 11m.

Amygdala↗

PubMed2006

Orbital based electronic structural signatures of the guanine keto G-7H/G-9H tautomer pair as studied using dual space analysis.

Electronic structural signatures of the guanine-7H and guanine-9H tautomers have been investigated on an orbital by orbital basis using dual space analysis. A combination of density functional theory (B3LYP/TZVP), the statistical average of model orbital potentials (SAOP/TZ2P) method and outer valence Green's function theory (OVGF/TZVP) has been used to generate optimal tautomer geometries and accurate ionization energy spectra for the guanine tautomer pair. The present work found that the non-planar form for both of the guanine keto pair possesses lower energies than their corresponding planar counterparts, and that the canonical form of the guanine-7H tautomer has slightly lower total energy than guanine-9H. This latter result is in agreement with previous experimental and theoretical findings. In the planar guanine pair the geometric parameters and anisotropic molecular properties are compared, focusing on changes caused by the mobile proton transfer. It is demonstrated that the mobile proton only causes limited disturbance to isotropic properties, such as geometry and the energetics, of the guanine keto tautomer pair. The exception to this general statement is for related local changes such as the N((7))-C((8)) and C((8))-N((9)) bond length resonance between the single and double bonds, reflecting the nitrogen atom being bonded with the mobile proton in the tautomers. The mobile proton distorts the electron distribution of the tautomers, which leads to significant changes in the molecular anisotropic properties. The dipole moment of guanine-7H is altered by about a factor of three, from 2.23 to 7.05 D (guanine-9H), and the molecular electrostatic potentials also reflect significant electron charge distortion. The outer valence orbital momentum distributions, which were obtained using the plane wave impulse approximation (PWIA), have demonstrated quantitatively that the outer valence orbitals of the tautomer pair can be divided into three groups. That is orbitals 1a''-7a'' and 18a', which do not have visible alternations in the tautomeric process (which consist of either pi orbitals or are close to the inner valence shell); a second group comprising orbitals 19a'-22a', 25a', 26a', 28a', 29a' and 31a', which show small perturbations as a result of the mobile hydrogen locations; and group three, orbitals 23a', 24a', 27a', 30a' and 32a', which demonstrate significant changes due to the mobile proton transfer and are therefore considered as signature orbitals of the G-7H/G-9H keto tautomeric process.

Guanine↗

PubMed2005

Away from generalized gradient approximation: orbital-dependent exchange-correlation functionals.

The local-density approximation of density functional theory (DFT) is remarkably accurate, for instance, for geometries and frequencies, and the generalized gradient approximations have also made bond energies quite reliable. Sometimes, however, one meets with failure in individual cases. One of the possible routes towards better functionals would be the incorporation of orbital dependence (which is an implicit density dependency) in the functionals. We discuss this approach both for energies and for response properties. One possibility is the use of the Hartree-Fock-type exchange energy expression as orbital-dependent functional. We will argue that in spite of the increasing popularity of this approach, it does not offer any advantage over Hartree-Fock for energies. We will advocate not to apply the separation of exchange and correlation, which is so ingrained in quantum chemistry, but to model both simultaneously. For response properties the energies and shapes of the virtual orbitals are crucial. We will discuss the benefits that Kohn-Sham potentials can offer which are derived from either an orbital-dependent energy functional, including the exact-exchange functional, or which can be obtained directly as orbital-dependent functional. We highlight the similarity of the Hartree-Fock and Kohn-Sham occupied orbitals and orbital energies, and the essentially different meanings the virtual orbitals and orbital energies have in these two models. We will show that these differences are beneficial for DFT in the case of localized excitations (in a small molecule or in a fragment), but are detrimental for charge-transfer excitations. Again, orbital dependency, in this case in the exchange-correlation kernel, offers a solution.

Journal Article↗

PubMed2005

Coexistence of 1,3-butadiene conformers in ionization energies and Dyson orbitals.

The minimum-energy structures on the torsional potential-energy surface of 1,3-butadiene have been studied quantum mechanically using a range of models including ab initio Hartree-Fock and second-order Møller-Plesset theories, outer valence Green's function, and density-functional theory with a hybrid functional and statistical average orbital potential model in order to understand the binding-energy (ionization energy) spectra and orbital cross sections observed by experiments. The unique full geometry optimization process locates the s-trans-1,3-butadiene as the global minimum structure and the s-gauche-1,3-butadiene as the local minimum structure. The latter possesses the dihedral angle of the central carbon bond of 32.81 degrees in agreement with the range of 30 degrees-41 degrees obtained by other theoretical models. Ionization energies in the outer valence space of the conformer pair have been obtained using Hartree-Fock, outer valence Green's function, and density-functional (statistical average orbital potentials) models, respectively. The Hartree-Fock results indicate that electron correlation (and orbital relaxation) effects become more significant towards the inner shell. The spectroscopic pole strengths calculated in the Green's function model are in the range of 0.85-0.91, suggesting that the independent particle picture is a good approximation in the present study. The binding energies from the density-functional (statisticaly averaged orbital potential) model are in good agreement with photoelectron spectroscopy, and the simulated Dyson orbitals in momentum space approximated by the density-functional orbitals using plane-wave impulse approximation agree well with those from experimental electron momentum spectroscopy. The coexistence of the conformer pair under the experimental conditions is supported by the approximated experimental binding-energy spectra due to the split conformer orbital energies, as well as the orbital momentum distributions of the mixed conformer pair observed in the orbital cross sections of electron momentum spectroscopy.

Butadienes↗

PubMed2000

Atoms in parallel fields: analysis with diffractive periodic orbits

We show that fluctuations in the density of states of nonhydrogenic atoms in parallel fields are strongly influenced by diffractive periodic orbits. Unlike typical systems with a diffractive point scatterer, the atomic core of small atoms like lithium and helium is best understood as a combined geometric and diffractive scatterer. Each Gutzwiller (geometric) periodic orbit is paired with a diffractive orbit of the same action. We investigate, particularly, amplitudes for contributions from repetitions, and multiple scattering orbits. We find that periodic orbit repetitions are described by "hybrid" orbits, combining both diffractive and geometric core scatters, and that by including all possible permutations we can obtain excellent agreement between the semiclassical model and accurate fully quantal calculations. For high repetitions, we find even one-scatter diffractive contributions become of the same order as those of the geometric periodic orbit for repetition numbers n approximately Planck's over 2pi(-1/2). Although the contribution of individual diffractive orbits is suppressed by O(Planck's over 2pi(1/2)) relative to the geometric periodic orbits, the proliferation of diffractive orbits with increasing period means that the diffractive effect for the atom can persist in the Planck's over 2pi-->0 limit.

Journal Article↗

PubMed1987

Orbital recurrence of retinoblastoma.

There were 16 cases of orbital recurrence in a consecutive series of 317 children with retinoblastoma referred to a specialist centre. The incidence of orbital relapse amongst children treated at the centre from the outset of their disease was 2.5%. In every case the patient was the first affected family member. The ocular tumour was therefore not anticipated and had commonly been detected at an advanced stage. Systemic staging investigations detected extraorbital spread in six of the 16 and none of these children survived. One of the remaining ten children with no evidence of dissemination at the time of diagnosis of orbital recurrence is a long-term survivor. No child survived after orbital exenteration or radical orbital radiotherapy alone. Three children received a combination of radiotherapy and adjuvant chemotherapy. Only one of the three was free from systemic disease at relapse and this child is the only survivor. In children apparently free from widespread retinoblastoma at diagnosis of orbital recurrence, distant relapse was the commonest cause of death though several children died from direct intracranial extension. It is advocated that orbital recurrence of retinoblastoma is treated by excision biopsy of the tumour mass followed by radical orbital radiotherapy to a dose of 50 Gy. This should be combined with adjuvant chemotherapy and, where a risk of direct intracranial extension exists, by neuraxis irradiation. No other child in this series with evidence of local extraocular extension of retinoblastoma at enucleation and who had received radical orbital radiotherapy to a full dose of 50 Gy subsequently recurred in the orbit.(ABSTRACT TRUNCATED AT 250 WORDS)

Child↗

PubMed1991

Orbit-related variation in spatial resolution as a source of artifactual defects in thallium-201 SPECT.

The cause of 180-degree diametrical artifactual defects in clinical thallium-201 SPECT imaging was investigated using phantom simulation. This artifact was observed on SPECT images acquired with a "body contour" or "peanut" orbit. It was hypothesized that this artifact was caused by differences in spatial resolution that occur when the heart-to-detector distance changes employing noncircular orbits. To test this hypothesis, a series of planar static images of a normal cylindrical phantom was obtained at varying distances from the camera detector head. From these images, tomographic acquisition files were created that simulated tomographic data acquired with circular orbits and elliptical orbits. The reconstructed phantom short-axis slices showed no artifacts for circular orbits. However, for various elliptical orbits, significant regional nonuniformity, similar to the artifacts noted in patients, was observed. The degree of nonuniformity correlated with the long-short axis ratio of elliptical orbits (r = 0.98). In addition, circular orbits with the phantom in an eccentric position resulted in similar nonuniformities. It is concluded that a noncircular tomographic orbit can create characteristic artifacts on thallium-201 SPECT images. For rotational thallium 201 SPECT, a circular orbit with the heart in the center of rotation should be employed.

Coronary Disease↗

PubMed2003

CT of orbital trauma.

In a patient with acute orbital trauma, visual acuity and extraocular muscle motility are the two most important ophthalmologic functions to be evaluated emergently. The assessment of these capabilities may sometimes be difficult due to the severity of the head injury, the extent of periorbital soft tissue edema, inadequate cooperation in alert patients, and a reduced level of consciousness in obtunded individuals. Consequently, computed tomography (CT) has come to play a major role in the orbital examination of acute trauma patients. In this study, in conjunction with clinical evaluation, we have sought to utilize CT to determine the various prevalences of the causes of decreased visual acuity and extraocular muscle motility resulting from orbital trauma. We retrospectively reviewed the records of all patients admitted to our emergency facility who, having suffered head trauma, underwent a CT study for diagnosis. CT examinations of the head using a multidetector scanner were performed from the base of the skull to the vertex at 5-mm intervals. Orbital CT was obtained when a routine CT of the head showed periorbital soft tissue edema and/or facial bone fractures. The orbital CT examination was performed using axial 1-mm and coronal 3-mm slices. Coronal reformation images were prepared if the patient was unable to tolerate the prone position for direct coronal imaging. The imaging findings were correlated with ophthalmologic observations. The orbit floor was the most common and the orbital roof the least common site of fracture of the bony coverings of the eye. Twenty-three patients suffered decreased visual acuity. In order of declining frequency, the causes of reduced vision consequent to trauma were retrobulbar hemorrhage, optic nerve thickening presumably secondary to edema, intraorbital emphysema, optic nerve impingement, detached retina and ruptured globe. Five patients had visual impairment without demonstratable radiographic abnormalities. The most common finding associated with diminished extraocular muscle motility was muscle impingement by fracture fragments, followed in decreasing frequency by thickened muscle due to edema or contusion, intraconal emphysema, muscle entrapment, and retrobulbar fat herniation. Six patients with decreased extraocular muscle activity had no abnormalities demonstrated on CT images. The overwhelming majority of patients with decreased visual acuity or reduced extraocular muscle motility consequent to trauma had abnormalities demonstrated by orbital CT. Hence, CT examinations should play a major role in the evaluation of the intraorbital contents in patients with orbital trauma.

Adolescent↗