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At least 37 records · Page 2Linked to original sources
PubMed1992

Stimulation of orbital growth by the use of expandable implants in the anophthalmic cat orbit.

We evaluated the efficacy of expandable orbital implants to stimulate bone growth in the anophthalmic cat orbit. Eighteen cats unilaterally enucleated at 2 weeks of age received either expandable orbital implants (groups A1 and A2), solid silicone sphere implants of 12 mm or 8 mm (groups B1 and B2), or no implant (group C). Those cats with expandable implants (group A) had the implant size increased by 0.5 ml injections of saline at 2-week intervals starting at 8 weeks of age until a final volume of 4 cc was reached. Four of the expandable implants were found to be only partially inflated at 20 weeks and were subgrouped A2. At 20 weeks of age, the anophthalmic orbits with fully inflated expanders showed no significant difference in either orbital volume or orbital entrance area when compared with control orbits: volume (91.2%), area (95.7%) (p = 0.01). These same orbits also showed a significant increase in both orbital volume and orbital entrance area when compared with the growth obtained by any other group. These other groups showed growth, expressed as a percentage of normal growth, as follows: partially inflated implant: volume (63.0%), area (69.0%); 12-mm sphere implant: volume (57.0%), area (54.5%); 8-mm sphere implant: volume (46.5%), area (44.6%); no implant: volume (47.6%), area (43.6%) (p = 0.01). This study suggests that the use of expandable orbital implants stimulates bony growth in the immature cat orbit. Bony stimulation was proportional to volume implanted, and expandable orbital implants achieved maximum bony stimulation in the groups studied.

Animals↗
PubMed2006

Frontal mucocele with an accompanying orbital abscess mimicking a fronto-orbital mucocele: case report.

BACKGROUND: Mucoceles are slowly expanding cystic lesions with respiratory epithelium containing mucus most commonly affecting the frontal and ethmoidal sinuses. They are caused by obstruction of sinus ostium. Mucoceles exert pressure on the bony boundaries and due to the proximity to the brain and orbit extension to these areas are common. CASE PRESENTATION: A case of a frontal mucocele with an accompanying orbital abscess mimicking a fronto-orbital mucocele is reported. A 77 year old female patient suffering from left sided proptosis and pain around the left eye was admitted to our department. She had a history of left frontal sinus mucocele one year ago that was offered an osteoplastic frontal sinus surgery that the patient refused. Patient had limitation of eye movements. Fundoscopic examination revealed a minimal papilledema. Coronal computerized tomography and orbital magnetic resonance imaging showed a frontal mucocele with suspicious erosion of the orbital roof and a superiorly localized extraconal mass displacing the orbit lateroinferiorly. Frontal and orbital masses had similar intensities. Thus surgery was planned for a fronto-orbital mucocele. During surgery no defect was found on the orbital roof. Frontal mucocele and orbital cystic mass was removed separately. Pathological examination showed a frontal mucocele and an orbital abscess wall. Postoperatively eye movements returned to normal and papilledema resolved. CONCLUSION: Fronto-orbital mucoceles are commonly encountered pathologies, but frontal mucocele with an orbital abscess is a rarely seen and should be kept in mind because their treatments differ.

Journal Article↗
PubMed1992

Complex orbital fracture repair using rigid fixation of the internal orbital skeleton.

Large orbital fractures involving more than one orbital wall are frequently associated with enophthalmos and vertical globe dystopia. The authors repaired 22 orbits in 20 patients using the technique of rigid fixation of the internal orbital skeleton. Eleven orbits were reconstructed with titanium or vitallium implants that were custom-shaped to span the bony defect and fixed to the orbital rim. Seven orbits were reconstructed with bone grafts rigidly supported by a miniplate, and, in four cases, direct lag screw support of bone grafts was used. The intraoperative goal was to restore the native orbital anatomy and volume. Autologous calvarial bone grafts were used to supplement the repair to achieve the desired volumetric effect and to cover additional wall defects. A reoperation for additional orbital augmentation was needed in one enophthalmic and one anophthalmic orbit. There were no cases of overcorrection, migration, infection, or extraocular muscle entrapment. In complex orbital fractures, the technique of rigid internal orbital fixation appears to yield a stable and predictable result with the prevention of postoperative globe malposition.

Adult↗
PubMed2006

[The orbital implant after exenteration of the orbit with the preservation of the eyelids and the conjunctival sac].

In ophthalmology, the orbital exenteration presents the most mutilating surgical procedure. The surgical technique presented by authors, preserves the eyelids and conjunctival sac. This surgical procedure was suggested and repeatedly performed in adult patients with extensive benign tumors (mostly meningeomas) by J. Otradovec and J. Safár. The enucleation of the eyeball preceded this type of surgery. The final state made it possible to put the prosthesis into the conjunctival sac. Today we inform about further development of this surgical technique and according to our own experiences we widen its indications to some malignant tumors (rhabdomyosarcoma and metastases of the retinoblastoma, etc.) in children. The initial cutaneous incision starts in the eyebrow area and is directed toward the bone of the orbital rim. The preparation of the tissue underneath the intact conjunctival sac to the lower aspect of the bone orbital rim follows. After folding the conjuctival-cutaneous sac back, the real content of the orbit is exenterated in the classical manner. After the hemostasis in the orbital apex, the flap is returned to its primary position and suturing of the primary incision in anatomical layers terminates the surgery. The authors refer about a boy, now 17 years old, who underwent at the age of three years the exenteration of the orbit in this manner due to a rhabdomyosarcoma. The authors also refer about the development and application of a special type of prosthesis made from silicone rubber--implant grade--filling out the orbital space and forming the anterior segment of the eye. The prosthesis was created from a classical orbital implant, regularly used in enucleation surgery and a conjunctival implant, a convex-concave plate with diameter of 20 mm. Both parts are made from the same type of silicon rubber and were connected together by vulcanization. The orbital implant was eliptically extended according to the measurements of the orbital casting made from dental impression matter. The cosmetic part, simulating the colored iris and the pupil, was prepared from a polyester sheet, painted with acrylic paint. It was fixated on the conjunctival prosthesis and covered with a transparent silicone foil. For the first time, the prosthesis was applied at the age of seven years, and during the next ten-years period, it was three times exchanged mostly for a bigger model. This procedure guaranteed proper growing of the orbital area and symmetrical development of the face. The prosthesis also carries out the prosthetic role and cosmetically it looks similarly like after the enucleation without the implant.

Child, Preschool↗
PubMed2000

Dimensions and volumes of the orbit and orbital fat in posttraumatic enophthalmos.

OBJECTIVES: To estimate from 2D and 3D-CT the anatomical defects that are most likely to be responsible for posttraumatic enophthalmos. MATERIALS AND METHODS: The morphology and dimensions of the orbit and of fat content were investigated in 25 patients 6-12 months after treatment for complex orbital fractures by image analysis and volumetric estimation from 2D and 3D-CT. RESULTS: The shape of orbit was very often changed from conical to more rounded due to enlargement of the posterior segment. The retrobulbar fat appeared fragmented and dislocated posteriorly. No changes were observed in the structural appearance or radiodensity of either the orbital fat or muscles. There was reduced sagittal eye projection, increased width of the orbital rim, downward dislocation of the posteromedial orbital floor, and increased volume in the posttraumatic orbits which was significantly different (P < 0.05). Enophthalmos was correlated with orbital volume and height of the retrobulbar portion of the orbit. The volume of fat did not correlate with enophthalmos. CONCLUSIONS: Posttraumatic enophthalmos appears to be more commonly related to failure in correcting the orbital volume and in reducing the outward dislocation of the posterior orbital floor and not to changes in the fat content.

Adipose Tissue↗
PubMed2002

[Orbital volume measurement of enophthalmos of orbital blowout fractures].

OBJECTIVE: To measure the volumetric changes of enophthalmos of orbital blowout fractures, and to study the relation between the change of the orbital volume and the degree of enophthalmos. METHODS: In 16 patients with enophthalmos of orbital blowout fractures, the measurement of orbital volume was carried out during 3 months to 2 years after injury by using the computed tomography (CT), computer image processing and computer orbital three-dimensional measuring method. The relation between the orbital volume discrepancy and enophthalmos was assessed by using Pearson correlation coefficients. RESULTS: There were significant linear correlation between the increment of the orbital volume and the degree of enophthalmos (r = 0.95, P < 0.001), with each 1.0 cm(3) increment in bony volume causing approximately 0.9 mm of enophthalmos. CONCLUSIONS: Orbital blowout fractures can expand the orbital volume. The measurement of orbital volume may predict the risk and the final degree of the enophthalmos at the late stage, thus it may provide useful information in surgical intervention to estimate the size and volume of the orbital implant for an individual case.

Adolescent↗
PubMed1988

[A new technique for the removal of orbital tumors--combined fronto-orbital approach].

Advances in the surgical approach to the orbital fossa have resulted in an increase in the cure of tumors involving the optic nerve and the external ocular muscles. In the past 10 years we have encountered 12 cases with orbital fossa tumors, excluding ocular tumors and inflammatory disease case. After tumor removal surgery, new neurological deficits such as total ophthalmoplegia were caused in many cases, where surgery was performed by classical Krönlein's technique or Dandy's transfrontal approach. So we thought that a new method for tumor removal should be contrived to improve postoperative results. Recently we have had four cases with large orbital tumors (3 cavernous angiomas and one schwannoma). In order to protect visual acuity and external ocular muscle function, we have devised a modification of the frontal craniotomy technique, the "combined fronto-orbital approach". Using our new method, we have successfully removed these four orbital tumors and with good postoperative results. We have concluded that our new technique is superior to other transfrontal approaches on several points as follows: 1) Decreased avoidable compression against the orbital contents and a decrease in the risk of tearing the frontal lobe dura and the peri-orbital during fronto-orbital craniotomy. 2) Satisfactory external decompression and a wide operative field are obtained with simple and safe procedures. 3) Previously detaching the superior rectal muscle makes it easy to distinguish the orbital fossa pathoanatomy and to remove a tumor. 4) Good results are easily obtained in the reconstruction of the orbital roof and the orbital rim, especially in the prevention of postoperative bulbar pulsation and from cosmetic view point.

Frontal Bone↗
PubMed1996

[The measurement of orbital volume in reconstruction of the orbital walls].

Before reconstruction of the orbital walls and other surgical procedures involving the orbits leading to a modification of pathologically altered orbital volumes, it is useful to measure these volumes in order to allow a more precise correction. Orbital volumetric studies on 22 patients and 6 dry skulls were performed using high resolution computer tomography. Fourteen patients presented enophthalmos of various origin, 3 patients fibrous dysplasia involving the orbits and 5 patients showed orbital pathology. In 10 patients with unilateral post-traumatic enophthalmos an increase of the bony orbital volume of 20.1% in the average was found corresponding to an enophthalmos of 3.5 mm in the average. Correlation between the severity of the enophthalmos and the increase in orbital volume was found. Enophthalmos could not be correlated to the intraorbital fat volume, especially no atrophy of orbital fat could be demonstrated in these patients. Normal orbital volume measurements of patients and dry skulls were compared to those found in the literature. Planning of the surgery was therefore facilitated before correction of enophthalmos, reconstruction of bony orbital contour after tumor-resection and in patients with fibrous dysplasia. Results suggest that the bony enlargement, followed by a change in soft-tissue shape and position is the usual cause of posttraumatic enophthalmos. Changes in volume of soft-tissues themselves are less significant.

Cadaver↗
PubMedDate not supplied

Measurement of orbital volume by computed tomography: especially on the growth of the orbit.

PURPOSE: Using reconstructed x-ray computed tomography (CT) images of serial coronal sections, we measured the orbital volume and studied its changes with age. METHODS: The subjects consisted of 109 patients (74 male, 35 female) who had undergone x-ray CT. After the reproducibility of orbital volume measurements and laterality in individuals were confirmed, the relation between the orbital volume and age, sex, weight, and interlateral orbital rim distance were examined. RESULTS: The difference between two measurements in the same patient stood at 0.4% for measured volume, which showed good reproducibility of this measurement. The laterality in individuals stood at 0.06 cm(3); the difference was very small and no significant difference was found. Moreover, the orbital volume did not show any imbalance between the right and left eyes in any stage of growth. Both the height and the interlateral orbital rim distance had a strong correlation with the orbital volume. CONCLUSION: Referring to the relation between age and orbital volume, a strong correlation with an almost identical approximate equation was obtained for both sexes until the age of 12. Presumably, the rapid growth of the orbit comes to an end by 15 years of age in boys and by 11 years in girls. This means that more than 95% of the growth of the adult orbit has already been completed by the first half of the teens. The mean orbital volume in adult Japanese is 23.6 +/- 2.0 cm(3) in men and 20.9 +/- 1.3 cm(3) in women.

Adolescent↗
PubMed2001

Reossification of the orbital wall following ventral translocation of the fronto-orbital bar and cranial vault remodeling.

The purposes of this study were to determine the extent of ossification of the orbit following ventral translocation of the fronto-orbital bar and to find out whether age at the time of the procedure and presence of a concomitant syndrome adversely affect ossification. A retrospective review of 27 patients with craniosynostosis was conducted at the St. Louis Children's Hospital and the Children's Hospital of Oklahoma. Patients with preoperative, perioperative, and postoperative three-dimensional computed tomography scans were included. Eighty-eight percent of the lateral orbital wall defects and 92 percent of the defects within the roof of the orbit ossified completely in the postoperative period. When syndromic patients were compared with nonsyndromic patients (based on clinical findings only), three of the 19 syndromic defects and three of the 30 nonsyndromic defects demonstrated incomplete ossification in the lateral orbital wall (p > 0.05). Similarly, two of the 19 syndromic defects and two of the 30 nonsyndromic defects demonstrated incomplete ossification within the roof of the orbit (p > 0.05). With respect to age at the time of the procedure, four of the 37 defects and two of the 12 defects demonstrated incomplete ossification in the lateral orbital wall for age at the time of the procedure less than 12 months and greater than 12 months, respectively (p > 0.05). Similarly, two of the 37 defects and two of the 12 defects had incomplete ossification within the roof of the orbit for age at the time of the procedure less than 12 months versus more than 12 months, respectively (p > 0.05). Ossification of the orbital wall and roof is complete in the majority of cases within 1 year after the procedure, and neither age at the time of the procedure nor presence of a concomitant syndrome adversely affects ossification of the orbit after ventral translocation of the fronto-orbital bandeau.

Bone Transplantation↗
PubMed2005

Theoretical revisit of regioselectivities of diels-alder reactions: orbital-based reevaluation of multicentered reactivity in terms of reactive hybrid orbitals.

When reactions proceed under kinetic control, stereoselectivities are determined from energetic properties of the transition state (TS). Orbital interaction at the TS plays a significant role in determining reactivity and selectivity, because it is directly related to lowering of the activation barrier. However, the orbital interaction at the TS cannot be represented only in terms of the frontier orbitals at the reactant state. A reactive hybrid orbital (RHO) that is localized at the reaction site is used to represent the orbital around the relevant TS in terms of a combination of the canonical molecular orbitals (MOs). This representation can make comparison of reactivities and selectivities among molecules of different sizes feasible. In this paper, the regioselectivities of Diels-Alder cycloaddition reactions of a monosubstituted butadiene and a dienophile (a monosubstituted ethylene) are investigated in terms of several parameters such as reactivity index and stabilization index, which are obtained on the basis of the newly developed multicentered version of the RHO method. These values can also be compared with the corresponding parameters defined on the basis of the frontier orbitals. Predictions of the regioselectivities based on the RHOs are consistent with experimental observations, while those based on the frontier orbitals are unreliable. This is because the RHO is superior to the frontier orbital as a descriptor of the orbital participating in orbital interactions around the TS.

Electrons↗
PubMed2005

[A comparative study between the results of antro-ethmoidal orbital decompression isolated and associated with orbital fat removal].

PURPOSE: To compare the results of isolated antral-ethmoidal orbital decompression and that associated with orbital fat removal in patients with dysthyroid orbitopathy. METHODS: Nineteen isolated antral-ethmoidal orbital decompressions were performed in a group of 12 patients (19 orbits) with the diagnosis of dysthyroid ophthalmopathy in the quiescent stage. The same procedure, but in association with orbital fat removal, were performed in another group of 8 patients (10 orbits) also with the diagnosis of dysthyroid ophthalmopathy in the quiescent stage. The results of both groups were compared. RESULTS: In the first group the amount of retroplacement of the globe achieved 1-5 mm (mean 3.68+/-1.10 mm) and in the second group it achieved 1-5 mm (mean 3.25+/-1.36 mm). CONCLUSIONS: There was no significant difference between the results of the isolated antral-ethmoidal orbital decompression and that associated with orbital fat removal. The removal of 1 ml of seems not to improve the retroplacement of the globe as an association with a 2-wall orbital decompression. However, many conditions must be considered to conclude any comparison between the two orbital decompression techniques, such as orbital soft tissue compliance, amount of fat removal and size of bone opening.

Adipose Tissue↗
PubMed2004

Orbital lymphoma: is it necessary to treat the entire orbit?

PURPOSE: Conformal radiotherapy (RT) has been used for all patients with orbital lymphoma treated at our institution since 1997. We retrospectively reviewed the charts of 23 consecutive patients to test the hypothesis that partial orbit RT is effective and less toxic than whole orbit RT. METHODS AND MATERIALS: Twelve patients with limited lesions were treated to partial orbital volumes and 11 patients (1 with bilateral disease) with more extensive lesions received whole orbit RT. The dose was 20-30 Gy (median, 25.2 Gy) for 19 patients with low-grade lymphoma and 24-40 Gy (median, 39.6 Gy) for 5 patients with intermediate- to high-grade lymphoma. The follow-up was 12-68 months (median, 34 months). RESULTS: All patients had a complete response to RT. Intraorbital recurrence developed in previously uninvolved areas not included in the initial target volume in 4 patients (33%) treated with partial orbit RT. All were salvaged by repeat RT or surgery. No patient treated with whole orbit RT developed intraorbital recurrence. The acute and long-term toxicity was similar in both groups. All but 1 patient retained good vision. CONCLUSION: Patients with orbital lymphoma should be treated to the entire orbit. An effective dose of RT for low-grade lesions is 25 Gy, which results in minimal morbidity even when delivered to the entire orbit.

Adult↗
PubMedDate not supplied

Orbital growth after unilateral enucleation in infancy without an orbital implant.

PURPOSE: To measure the volume of the anophthalmic orbit in adults who had undergone enucleation during infancy and to determine its growth. METHODS: The orbital volume in 5 adults who had undergone unilateral enucleation during infancy without an orbital implant was measured on x-ray computed tomography images. Comparisons were made between the anophthalmic and normal sides. In addition, we evaluated the morphology of the orbits showing growth retardation and the association between the prosthesis, if present, and orbital growth. RESULTS: In adults who underwent unilateral enucleation as infants, without an orbital implant, orbital growth was more retarded on the anophthalmic side than on the normal side. The difference was most marked in the area corresponding to the equator of the eyeball. This growth retardation was more severe in patients whose prosthesis was not replaced during childhood than in those who had regular replacement of their prosthesis. CONCLUSION: For orbital growth in anophthalmic orbits, an intraorbital volume that replaces the eyeball is necessary. An orbital implant at the time of enucleation and the replacement of the prosthesis with growth are important.

Adult↗
PubMed1993

The role of orbital ultrasound in the diagnosis of orbital fractures.

The role of CT scanning in the diagnosis and management of craniomaxillofacial injuries is well documented. However, coexistent injuries, limitations on patient positioning, CT availability, or financial constraints may prevent or delay the diagnosis of significant orbital wall defects. Real-time ultrasound represents a safe, inexpensive, noninvasive, portable, and readily available diagnostic modality which has had a limited application in the diagnosis of orbital pathology. The objectives of this study were to define the role of orbital ultrasound in the assessment of the traumatized orbit and to provide correlation of pathology with CT imaging. Eighteen patients (16 males, 2 females) having sustained trauma to the orbitozygomatic region were assessed at a regional trauma center over a 6-month period. Each patient underwent an ultrasound examination of both orbits. Confirmatory CT scans (5-mm axial and 1.5-mm coronal orbital cuts) were then obtained for comparative assessment. Patients with open globe injuries, alteration of visual acuity, or life-threatening conditions were excluded from the study. The results of the study revealed a positive correlation between the ultrasound and CT findings in 17 (94 percent) of the patients. Ultrasound demonstrated satisfactory sensitivity (92 percent) and specificity (100 percent) and positive predictive value (100 percent) when compared with CT scanning. Soft-tissue herniation, orbital emphysema, and muscle entrapment were well visualized by means of real-time ultrasound. It is concluded that orbital ultrasound is an accurate diagnostic modality in the investigation of orbital trauma and correlates well with CT findings. A cost analysis will be presented, and details of the limitations and efficacy of orbital ultrasound will be discussed.

Adult↗
PubMed1976

Carcinoma metastatic to the eye and orbit III. A clinicopathologic study of 28 cases metastatic to the orbit.

Two hundred and twenty-seven cases of carcinoma metastatic to the eye and orbit have been reviewed previously. The orbit alone was involved in 28 cases: theses lesions constitute the basis of this clinicopathologic study. The most common signs and symptoms produced by orbital metastasis included exophthalmos (75%1, pain (29%), decreased vision (29%), periorbital swelling (25%), a visible mass (21%), ophthalmoplegia, and diplopia (18%). The ophthalmologists' preoperative (or premortem) clinical diagnoses were: orbital mass, 36%; metastatic carcinoma, 29%; leukemia, 7%; melanosarcoma, 4%; mixed tumor of lacrimal gland, 4%; and meningioma, 4%. The sites of the primary tumors in the 28 patients with orbital metastasis were as follows: breast, eight; lung, four; genitourinary tract, four; pancreas, one; and ileum, one. In 10 patients the site of the primary carcinoma was not determined. In 17 of the 28 patients, symptoms of orbital metastasis preceded detection of a primary tumor elsewhere in the body. In 10 of the remaining 11 patients, detection of the primary tumor had preceded the onset of orbital symptoms. In one patient, symptoms of the primary tumor and of orbital metastasis appeared at about the same time. The median survival of patients with carcinoma metastatic to the orbit was 15.6 months from the time of orbital surgery. This was much better than the median survival of the 227 patients in the overall study (7.4 months) and far better than the median survival of the patients with metastasis to the anterior segment of the eye (only 5.4 months).

Adenocarcinoma↗