Lateral Orbital Wall Research Articles

Management of Displaced Lateral Orbital Wall Fractures Associated with Visual and Ocular Motility Disturbances

Management of Displaced Lateral Orbital Wall Fractures Associated with Visual and Ocular Motility Disturbances

Lateral approach to the orbit: an anatomical study.

The authors have identified and described three lateral approaches to the intraorbital portion of the optic nerve in cadavers. The structures exposed via the superior, inferior or central approaches were directed through the lateral orbital wall. The superior approach in which the lateral rectus muscle is retracted inferiorly exposes the superolateral aspect of the orbit. The inferior approach in which the lateral rectus muscle is retracted superiorly, provided the inferolateral aspect of the optic nerve from the globe to the muscle cone. The central approach in which the lateral rectus muscle was disinserted and retracted provided excellent exposure of the structures of the lateral part of the orbit and the optic nerve. There were no structures blocking access to the ciliary ganglion and two third anterior optic nerve and lateral surface of the globe. The structures encountered in these approaches are demonstrated under magnification in cadavers, and the exposure of the optic nerve is discussed.

New instrument for orbital anthropometry

A new instrument for orbital anthropometry is described. It consists of the base for a slit-lamp upon which the patient's head rests and rulers mounted on three independently movable axes. The z-axis probe is used to measure sagittal relationship between the corneal apices and points on the orbital perimeter. The instrument was tested against a sliding caliper and its accuracy was found to be within 0.2 mm or 2%. Intra- and inter-observer reliability were assessed by repeated measurements of two subjects by three observers. The intra-observer reliability was 0.99. Variations between observers was not significantly different for points orbitale inferius (oi), nasion (n), and orbitale superius (os), however, there was a statistically significant difference for measurement of orbitale laterale (ol). The correlation between anthropometric readings for lateral orbital wall to apex corneal (ol-ac) and CT scans for the same landmarks was assessed. Analysis of variance showed no difference between the measurement methods. This anthropometer is convenient and accurate for measurement of the sagittal orbital-globe relationships. A disadvantage is that it cannot be used intraoperatively.

Maximal, Three-Wall, Orbital Decompression Through a Coronal Approach

Only limited volume expansion is offered by traditional lateral orbital decompressions in which the anterior segment of the lateral wall is removed to allow lateral soft tissue prolapse. A great deal of additional soft tissue expansion can be obtained, not only laterally, but also posteriorly by removing the deep portion of the sphenoid wing. The authors report their experience in removing this bone through a coronal approach. The authors performed maximal, three-wall, orbital decompressions through a coronal approach for 20 patients with thyroid-related orbitopathy. A disfiguring proptosis resulting from stable Graves' disease orbitopathy was the indication for surgery in all cases. Through a coronal approach, the lateral rim was left in place and thinned, augmented with specialized orbital rim onlay implants, or repositioned with osteosynthesis systems. The bone over the lacrimal fossa was sculpted to form a "keyhole" for the lacrimal gland, thereby providing additional orbital expansion. Once the medial canthal tendon and lacrimal sac had been elevated from their periosteal attachment, excellent exposure was obtained for medial and inferior orbital decompression. The authors report the results of 20 coronal orbital decompressions during a period of 44 months. Seven cases included lateral rim advancement. Up to 6 mm of retrodisplacement was achieved without rim augmentation, 9 mm with rim augmentation. The deep lateral orbital wall can provide significant room for volume expansion. The authors found that up to 6 mm of proptosis reduction can be obtained using the lateral wall alone. The coronal approach provides access to all four orbital walls for deep orbital decompression. The authors' philosophy of treatment in cases without compressive optic neuropathy is evolving toward the use of the lateral wall as the first approach with the incorporation of additional walls as needed.

Frontal Basilar Trauma: Classification and Treatment

We report our experience with 14 consecutive cases of frontal basilar trauma occurring in children and adolescents aged 18 months to 18 years (mean 9.5 years). Brain parenchymal injury resulting in functional deficit occurred in 5 patients (36 percent), 2 patients suffered bilateral blindness, and 1 suffered unilateral loss of vision. A classification system and treatment algorithm based on the clinical fracture pattern seen by computed tomography are introduced. Type I, central, is confined to the upper nasoethmoidal complex, central frontal bone, and medial third of the superior orbital rims. Type II, unilateral, involves the entire supraorbital rim and the upper lateral orbital wall, extending into the squamosa of the temporal bone and ipsilateral frontal bone. Type III, bilateral, involves fractures of the upper nasal ethmoidal complex, bilateral supraorbital and upper lateral orbital wall fractures, and bilateral frontal bone fractures. This classification was utilized to plan elective orbital and cranial osteotomies, similar to those used for frontal orbital advancement at the time of acute fracture repair. Frontal orbital osteotomies were used to access the anterior cranial fossa, orbital apices, and nasofrontal ducts and to obtain an intact bony template for side-table reassembly of the fracture fragments. There was no significant operative morbidity, one late cerebrospinal fluid leak, and no infections. Reoperation was necessary in four patients (29 percent) for aesthetic indications.

Frontal basilar trauma: classification and treatment.

We report our experience with 14 consecutive cases of frontal basilar trauma occurring in children and adolescents aged 18 months to 18 years (mean 9.5 years). Brain parenchymal injury resulting in functional deficit occurred in 5 patients (36 percent), 2 patients suffered bilateral blindness, and 1 suffered unilateral loss of vision. A classification system and treatment algorithm based on the clinical fracture pattern seen by computed tomography are introduced. Type I, central, is confined to the upper nasoethmoidal complex, central frontal bone, and medial third of the superior orbital rims. Type II, unilateral, involves the entire supraorbital rim and the upper lateral orbital wall, extending into the squamosa of the temporal bone and ipsilateral frontal bone. Type III, bilateral, involves fractures of the upper nasal ethmoidal complex, bilateral supraorbital and upper lateral orbital wall fractures, and bilateral frontal bone fractures. This classification was utilized to plan elective orbital and cranial osteotomies, similar to those used for frontal orbital advancement at the time of acute fracture repair. Frontal orbital osteotomies were used to access the anterior cranial fossa, orbital apices, and nasofrontal ducts and to obtain an intact bony template for side-table reassembly of the fracture fragments. There was no significant operative morbidity, one late cerebrospinal fluid leak, and no infections. Reoperation was necessary in four patients (29 percent) for aesthetic indications.

Lateral orbitectomy for correction of endocrine ophthalmopathy

Grave's disease is often associated with various symptoms summarized as endocrine orbitopathy. A surgical procedure is presented which reduces the exophthalmos by approximately 4.5 mm by resecting the caudal and lateral orbital wall through a subciliar incision. The surgical intervention regularly leads to an amelioration of the functional symptoms of endocrine orbitopathy, such as diplopia, corneal exposure and lid irregularities. In one case an acute reduction of vision on both eyes significantly ameliorated immediately after surgery. The operation described also improves the aesthetic appearance of the patients, who often suffer psychologic impairments associated with Grave's disease.

Idiopathic Hypertrophic Cranial Pachymeningitis

We present the clinical, radiological, and pathological findings in an elderly man who developed a progressive superior orbital fissure syndrome due to idiopathic hypertrophic cranial pachymeningitis. The unique aspect of this case concerned the increased density of the sphenoid ridge and lateral orbital wall observed by using computed tomography, and the enhancement of the marrow signal seen on magnetic resonance imaging. These neuroimaging abnormalities of bone resulted from an indirect nonspecific response of the marrow to the adjacent soft tissue and dural inflammatory process.

Evaluation of the anatomical position of the lateral canthal ligament: clinical implications and guidelines.

Controversy exists in the literature as to the precise anatomical location of the lateral canthal ligament. The ligament is a 3 mm-wide, two-tailed band; its average length is approximately 13 mm, while the width of the rima palpebralis is about 26 mm. The authors evaluated three different groups to pinpoint the anatomical position of the ligament's attachment to the lateral orbital wall, and to establish guidelines for placement of the ligament during surgery. In 90% of the cases, the ligament was attached to Whitnall's tubercle, which is located approximately 4 mm posterior to the lateral orbital rim, and 17 mm above the intersection of the lateral and inferior margins; this area is 9 mm below the zygomaticofrontal suture. Based on these anatomical criteria, a standardized procedure is suggested.

A surgical technique to avoid postoperative enophthalmos in the cranioorbital approach. Technical note.

The authors describe a surgical technique to avoid postoperative enophthalmos when using the cranioorbital approach. To perform osteotomies with a less demanding technique, two separate bone flaps were created: 1) a free frontotemporal bone flap and 2) en bloc removal of the superior and lateral orbital rims: Because the latter bone flap includes both the orbital roof and the posterolateral wall of the orbit with the greater wing of the sphenoid bone, unnecessary bone defects in the lateral orbital wall are avoided. The technique has been performed in seven patients treated for medially located skull base neoplasms or complex anterior circulation aneurysms without postoperative enophthalmos or other cosmetic problems. The authors believe this cranioorbital approach, with its simpler, less invasive surgical technique, offers a definite advantage by avoiding postoperative enophthalmos.

Functional anatomy of the levator palpebrae superioris muscle and its connective tissue system.

The connective tissue system of the levator palpebrae superioris muscle (LPS) consists of the septa surrounding its muscle sheath, the superior transverse ligament (STL) commonly referred to as 'Whitnall's ligament' and the common sheath which is the fascia between the LPS and the superior rectus muscle (SRM). The anterior band-like component of the common sheath is called transverse superior fascial expansion (TSFE) of the SRM and LPS. It mainly extends from the connective tissue of the trochlea to the fascia of the lacrimal gland. A detailed description of the relation between the LPS and its connective tissue is presented. Furthermore, the course of the LPS in the orbit is described. The study was conducted to provide a morphological basis for biomechanical and clinical considerations regarding ptosis surgery. Postmortem dissections were performed in 16 orbits from eight cadavers. The microscopical anatomy was demonstrated in six formalin preserved orbits from six cadavers which had been sectioned in the frontal and sagittal plane and stained with haematoxylin and azophloxin. Surface coil magnetic resonance imaging in the sagittal and coronal plane was performed in five orbits from five normal volunteers using a T1 weighted spin echo sequence. The STL and the TSFE surround the LPS to form a fascial sleeve around the muscle which has attachments to the medial and lateral orbital wall. The TSFE, which is thicker than the STL, blends with Tenon's capsule. The STL and the fascial sheath of the LPS muscle are suspended from the orbital roof by a framework of radial connective tissue septa. MR images show that the TSFE is located between the anterior third of the superior rectus muscle and the segment of the LPS muscle where it changes its course from upwards to downwards. In this area, the LPS reaches its highest point in the orbit (culmination point). The culmination point is located a few millimetres posterior to the equator and superior to the globe. Whitnall's ligament can be considered to consist of two distinct parts--the TSFE inferior to the LPS and the STL superior to the LPS. Since the medial and lateral main attachments of Whitnall's ligament are situated inferior to the level of the culmination point of the LPS, the ligament itself is unlikely to suspend the levator muscle. However, a suspension of the LPS may be achieved by the radial connective tissue septa of the superior orbit. The TSFE in connection with the globe may have an additional supporting function. The elasticity of Whitnall's ligament and its connections with highly elastic structures including Tenon's capsule, may provide the morphological substrate for the previously proposed passive (that is, without orbicularis action) lowering of the lid during downward saccades.

Three-dimensional expansion of growing orbit using a distraction device

Metopic synostosis is characterized by trigonocephaly, lateral supraorbital retrusion, and hypotelorism. Most phenotypic evaluations have focused on the forehead without much emphasis on the orbits. The study seeks to explore differences in orbital dysmorphology for metopic and control patients, along with different degrees of metopic synostosis.Demographic and craniometric data were compiled. CT scans were digitized (Materialise) and metopic and control groups were compared. Degree of trigonocephaly was classified into moderate and severe cases based on endocranial bifrontal angle. Orbital plane angle, width, depth, volume, and corneal projection were measured. Statistical two-paired t-tests were used, with significance determined as p < 0.05.Forty-six CT scans were analyzed (23 affected, 23 controls). Mean ages (6 months metopic, 7 months control) and genders (18 males metopic, 10 males control) were determined. Orbital plane angle measurements showed differences between the metopic and the control (p = 0.0002), along with a correlation to trigonocephaly (p = 0.0097). Orbital width and height were insignificant between controls and overall metopics, though height was less in severe metopics (p = 0.046 left, p = 0.0337 right). Orbital Depth was significant between control and metopics (p = 0.0106 left, p = 0.0025 right), and pronounced in severe cases p = 0.0349 left, p = 0.0071 right). Corneal Projection correlates with metopic severity (p < 0.01 left, right), while orbital volume showed insignificant change between control and metopic cases.Orbital dysmorphology worsens with increasing degree of trigonocephaly, presenting additional functional defects. The true exorbitism most directly correlates with worsening trigonocephaly. Expanding and advancing the lateral orbital wall is a critical treatment element in correction.III.

A radiologic and anatomic study of the lateral orbital wall osteotomy in orbital surgery: M. S. Dover, T. K. Mellor

A radiologic and anatomic study of the lateral orbital wall osteotomy in orbital surgery: M. S. Dover, T. K. Mellor

Technique for horizontalization of downward bowed, subluxated and ectropionic lower eyelids

Downward bowing and/or subluxation of the lower eyelid for reasons of paresis, tissue redundancy, or downward and outward push from behind and above (as in the shallow orbits of Crouzon's or trisomy 21 patients) but not from cicatrization is addressed surgically here with a new technique, designated 'horizontalization'. Herein, the geometric principle of three points of tension establishing a plane, beyond the confines of which deforming forces are hard put to act, is utilized.Starting with the 'tarsal strip procedure' of Anderson et al,16 18 an additional suture is passed through the disinserted and foreshortened lateral end of the inferior tarsotendinous sling. One of these sutures is then passed far posteriorly on the lateral orbital wall, to adhere to the periosteum about 1 cm behind the lateral orbital rim while the other is attached more or less at the orbital rim itself-both at the level of the normal lateral canthal attachments. When both of these sutures have been tied and cut, the inferior tarsotendinous sling behaves like a taut hammock and its edge tends to remain in a horizontal, axial plane despite downward pressure from the corneal bulge in downward gaze. It also follows the lower limbus in gaze upward rather than lag behind and below it.Patients with inferior corneal exposure problems benefit from this method both functionally and cosmetically (i.e, there are no skin incisions or palpebral deforming qualities as in tarsorrhaphies, tarsal pillar procedures, or lower lid elevating implants).

Intraorbital tissue expansion in the management of congenital anophthalmos

Seven cases of intraorbital tissue expansion for the treatment of congenital anophthalmos or microphthalmos are presented. The ages of the patients at insertion of the expander ranged from 4 months to 8 years. A 4ml spherical tissue expander with a remote injection port was inserted into the affected orbit via a bicoronal approach. Expansion periods ranged between 4 months and 3 years and are continuing in 2 patients. Results were assessed by clinical examination, comparison of photographs, 3D CT scans and orbital measurements taken from axial CT scans which were compared with established normal values. Results confirmed enlargement of the orbit with expansion. Long-term expansion over several years established near normal bony growth patterns. Placement of the expander within the orbital soft tissue cone resulted in more symmetrical expansion than subperiosteal placement. An osteotomy releasing the lateral orbital wall in older children allows expansion of the orbit and may reduce the incidence of expander extrusion. Although intraorbital tissue expansion successfully induces orbital growth, improvement in the form and size of the congenitally deficient eyelids is less marked.

Monobloc and facial bipartition osteotomies: Quantitative assessment of presenting deformity and surgical results based on computed tomography scans

The results of monobloc (MB) or facial bipartition (FB) osteotomies on 23 consecutive patients operated on between 1987 and 1991 were evaluated.A previously described method of clinically relevant linear measurements taken from preoperative and postoperative computed tomographic scans of these patients was used to document their presenting dysmorphology and the results of surgical correction initially and 1 year after operation. These data were compared with control values, and a percentage of normal for each measurement was derived for each patient.In the patients with craniofacial dysostosis undergoing an MB osteotomy, the initial cranial vault length (87% of normal), medial orbital wall length (87%), zygomatic arch length (84%), and extent of globe protrusion (134%) all indicated horizontal (anterior-posterior) deficiency of the upper and middle face. After surgery, these measurements moved closer to age-matched control values. At the 1-year interval a minor degree of relapse was evident. In the patients with craniofacial dysostosis who were believed to need an FB osteotomy, the globe protrusion (142% of normal), medial orbital wall length (85%), and zygomatic arch lengths (83%) all indicated horizontal (anterior-posterior) deficiency in the upper and middle face. In addition, the anterior interorbital distance (123% of normal), mid-interorbital distance (122%), and intertemporal distance (126%) all indicated upper face hypertelorism. As a result of the FB osteotomy, anterior bony projection was achieved, and the hypertelorism was improved, but fell short of age-matched normal values. In the patients with frontonasal dysplasia, cranio-orbital clefting, and isolated orbital hypertelorism who underwent an FB osteotomy, preoperative measurements showed a distinct widening of the whole upper midface with forward projection of the medial relative to the lateral orbital walls. The orbital measurements revealed a substantially widened anterior interorbital distance (175% of normal), increased mid-interorbital distance (123%), and an increased distance between the lateral orbital walls (106%). After the surgical procedure, these measurements were improved and relatively stable but not completely normalized.The use of quantitative measurements in the initial evaluation, intraoperative skeletal reshaping, and assessment of early and late reconstructive results provides useful benchmarks.

Monobloc and facial bipartition osteotomies: Quantitative assessment of presenting deformity and surgical results based on computed tomography scans

Purpose: The results of monobloc (MB) or facial bipartition (FB) osteotomies on 23 consecutive patients operated on between 1987 and 1991 were evaluated. Patients and Methods: A previously described method of clinically relevant linear measurements taken from preoperative and postoperative computed tomographic scans of these patients was used to document their presenting dysmorphology and the results of surgical correction initially and 1 year after operation. These data were compared with control values, and a percentage of normal for each measurement was derived for each patient. Results: In the patients with craniofacial dysostosis undergoing an MB osteotomy, the initial cranial vault length (87% of normal), medial orbital wall length (87%), zygomatic arch length (84%), and extent of globe protrusion (134%) all indicated horizontal (anterior-posterior) deficiency of the upper and middle face. After surgery, these measurements moved closer to age-matched control values. At the 1-year interval a minor degree of relapse was evident. In the patients with craniofacial dysostosis who were believed to need an FB osteotomy, the globe protrusion (142% of normal), medial orbital wall length (85%), and zygomatic arch lengths (83%) all indicated horizontal (anterior-posterior) deficiency in the upper and middle face. In addition, the anterior interorbital distance (123% of normal), mid-interorbital distance (122%), and intertemporal distance (126%) all indicated upper face hypertelorism. As a result of the FB osteotomy, anterior bony projection was achieved, and the hypertelorism was improved, but fell short of age-matched normal values. In the patients with frontonasal dysplasia, cranio-orbital clefting, and isolated orbital hypertelorism who underwent an FB osteotomy, preoperative measurements showed a distinct widening of the whole upper midface with forward projection of the medial relative to the lateral orbital walls. The orbital measurements revealed a substantially widened anterior interorbital distance (175% of normal), increased mid-interorbital distance (123%), and an increased distance between the lateral orbital walls (106%). After the surgical procedure, these measurements were improved and relatively stable but not completely normalized. Conclusion: The use of quantitative measurements in the initial evaluation, intraoperative skeletal reshaping, and assessment of early and late reconstructive results provides useful benchmarks.

Correction of post-traumatic orbital deformities: operative techniques and review of 26 patients

The skeletal reconstruction of post-traumatic orbital deformities includes the zygomatic complex, the nasoethmoid area and the internal orbit. Repositioning of the malpositioned zygoma is the key element and the first step. Due to remodelling processes, most of the landmarks for proper positioning are lost, leaving the lateral orbital wall as the only reliable landmark in secondary revisions. The details of the skeletal reconstruction are discussed. Between January 1988 and December 1992, 31 patients with major post-traumatic orbital deformities have been operated on, of which 26 could be followed for a minimum of 6 months. A total of 61 operative procedures using craniofacial techniques have been performed. Complications occurred in 5 (15%) of the 26 patients, the most severe being visual loss caused by a displaced bone graft. The most frequent deformity was enophthalmos. Most patients presented with more than one deformity. The aesthetic results were rated as 'good' in 12, 'satisfactory' in 8 and 'unsatisfactory' in 6 patients. Of the patients suffering from double vision, 55% were improved after orbital reconstruction. Craniofacial techniques allow radical correction of post-traumatic skeletal deformities. The functional and aesthetic results, however, are limited by the soft tissues.

Cranio-Orbito-Zygomatic Measurements from Standard CT Scans in Unoperated Treacher Collins Syndrome Patients: Comparison with Normal Controls

Fourteen reproducible cranio-orbito-zygomatic measurements taken from 26 standard axial computed tomographic (CT) scans of unoperated individuals with symmetric forms of Treacher Collins syndrome (TCS) were compared to age-matched controls. The interorbital measurements of the TCS patients were at the mean when compared to their cohort group (medial and lateral orbital wall separation), while the zygomatic measurements were significantly less than normal confirming the extent of malar hypoplasia. The congenitally deficient lateral aspect of the orbits in TCS patients was confirmed by the greater than normal values measured for globe protrusion and medial orbital wall protrusion in conjunction with the diminished lateral orbital wall lengths, all of which use the lateral orbital rim as a reference point. The abnormal shape of the anterior cranial vault in patients with TCS was documented as a diminished intercoronal distance (width) and decreased cephalic length when compared to normal age-matched controls.

Cranio-Orbito-Zygomatic Measurements from Standard CT Scans in Unoperated Treacher Collins Syndrome Patients: Comparison with Normal Controls

Fourteen reproducible cranio-orbito-zygomatic measurements taken from 26 standard axial computed tomographic (CT) scans of unoperated individuals with symmetric forms of Treacher Collins syndrome (TCS) were compared to age-matched controls. The interorbital measurements of the TCS patients were at the mean when compared to their cohort group (medial and lateral orbital wall separation), while the zygomatic measurements were significantly less than normal confirming the extent of malar hypoplasia. The congenitally deficient lateral aspect of the orbits in TCS patients was confirmed by the greater than normal values measured for globe protrusion and medial orbital wall protrusion in conjunction with the diminished lateral orbital wall lengths, all of which use the lateral orbital rim as a reference point. The abnormal shape of the anterior cranial vault in patients with TCS was documented as a diminished intercoronal distance (width) and decreased cephalic length when compared to normal age-matched controls.