Intra-operative navigation for orbital reconstruction to correct diplopia and enophthalmos with endoscopic assisted technique: first case report in Thailand

BACKGROUND AND OBJECTIVE

In an orbital fracture involving diplopia, enophthalmos is a major problem to be corrected because ofsoft tissue swelling and limited incision, which causes inaccurate restoration oforbital anatomy and reestablishing orbital volume. Pre-operative computerized planning combined with intra-operative navigation and endoscopy are used to create the accurate anatomical orbital position and effectively correct the posttraumatic diplopia and enophthalmos.

CASE REPORT

An 18-year-old Thai male with diplopia and enophthalmospresented aposttraumatic left orbital fracture two months prior Three-dimensional CTscan of the facial bone confirmed the fracture. The patient required surgical treatment for correction of the orbital fracture. The intra-operative navigator and endoscopy-assisted technique were used. Pre- and post-operative pictures were compared, indicated the successful correction of enophthalmos and clinical correction of diplopia.

CONCLUSION

Intra-operative navigator combined with endoscopy-assisted technique were a new surgical procedure that could correct the orbital deformity problem involving enophthalmos and diplopia more effective.

Silent sinus syndrome causing cyclovertical diplopia masquerading as superior oblique paresis in the fellow eye

Silent sinus syndrome is an insidious maxillary sinus inflammatory disease causing a lowering, thinning, or even absorption of the orbital floor. Patients usually present with progressive enophthalmos and hypoglobus. We report a 41-year-old man with silent sinus syndrome who presented with cyclovertical diplopia masquerading as superior oblique muscle paresis in the fellow eye. Inferior oblique myectomy in the fellow eye resulted in excellent alignment.

Silent sinus syndrome with spontaneous orbital floor reconstruction

PROBLEM

Silent sinus syndrome is rare and its pathophysiology is unclear. We report a case of silent sinus syndrome characterized by progressive enophtalmos with chronic maxillary atelectasis and asymptomatic chronic maxillary sinusitis.

METHODOLOGY

The patient had no history of sinusitis, facial trauma, or sinus surgery. Computed tomography revealed opacification of the right maxillary sinus and inferior bowing of the osteopenic orbital floor. Silent sinus syndrome was diagnosed and functional endoscopic maxillary antrostomy without orbital floor reconstruction was performed.

RESULTS

At one-year follow-up, computed tomography showed optimal ventilation of the maxillary sinus, restoration of the orbital floor, and withdrawal of the orbital content to its normal position.

CONCLUSION

Endoscopic maxillary antrostomy without orbital floor reconstruction is effective and associated with limited risks for complications; however, the results are observed in the long term.

Non-traumatic enophthalmos: a review

Enophthalmos can be defined as a relative, posterior displacement of a normal-sized globe in relation to the bony orbital margin. Non-traumatic enophthalmos has a wide variety of clinical presentations and may be the first manifestation of a number of local or systemic conditions. It may present with cosmetic problems such as deep superior sulcus, pseudoptosis or eyelid retraction; or functional problems such as diplopia or exposure keratopathy. There are three main pathogenic mechanisms: structural alterations in the bony orbit; orbital fat atrophy; and retraction. Evaluation of enophthalmos patients includes orbital imaging and a thorough ophthalmic and systemic examination. In this review, we discuss the presenting features of non-traumatic enophthalmos and include a brief description of the more important causes. An approach to the clinical evaluation of these patients is also discussed together with a brief overview of the principles of management.

[An alternative method for the correction of enophthalmos: deep lateral orbital approach]

Both increased orbital volume due to inadequate orbital floor reconstruction and loss of orbital volume may result in enophthalmos. Enophthalmos, vertical dystopia, and "lateral scleral show" deformity were detected in a 33-year-old female patient who presented with periorbital deformities after three operations for the correction of traumatic zygomatic fracture. First, vertical dystopia was repaired by reinforcing the orbital base with cranial bone grafting. Since enophthalmos was not successfully corrected, orbital volume augmentation was performed using the deep lateral wall through an upper eyelid crease incision. The only postoperative complaint was edema which was controlled by application of ice.

The relationship between enophthalmos, linear displacement, and volume change in experimentally recreated orbital fractures

PURPOSE

The purpose of this investigation was to establish the relationship between enophthalmos, linear displacement, and volume change for various patterns of experimentally recreated orbital fractures.

MATERIALS AND METHODS

We fabricated an experimental apparatus that permitted uniform displacement of simulated orbital wall fractures. Measurements of linear displacement, volume change, and degree of simulated enophthalmos were taken for 1- and 2-walled displacements. Means and standard deviations were derived, and analysis of variance was used to compare means for statistically significant differences ( P < .05) between groups and among major categories.

RESULTS

No statistically significant differences were found for any uniform displacement caused by 1-walled defects or for any given displacement caused by 2-walled defects The linear coefficient for displacement and enophthalmos or for displacement and volume change approached 1.0 for all groups (range, 0.9802 to 0.9999). However, statistically significant differences in mean enophthalmos and mean volume change at uniform displacements were found between 1- and 2-walled defects.

CONCLUSIONS

Displacement of 1- and 2-walled orbital defects results in a direct and linear change in both orbital volume and enophthalmos, regardless of the location of the defect.

Lagophthalmos in enophthalmic eyes

AIMS

To report a case series of enophthalmic patients with lagophthalmos.

METHODS

A retrospective review of the electronic medical records at a tertiary health care centre of all patients with the diagnoses of "enophthalmos" and "lagophthalmos". Patients who had a history of diseases (such as Graves' orbitopathy), trauma or surgery of the orbit and eyelid were excluded. Enophthalmos was defined as exophthalmometric reading of 14 mm or less in both eyes.

RESULTS

Seven patients (14 eyes) with bilateral enophthalmos were found to have concomitant lagophthalmos. All patients had deep superior sulci bilaterally. The upper eyelids were seen to be severely retro-placed behind the superior orbital rim. The extraocular motilities were full with no focal neurological deficit. The orbicularis oculi function was normal with no facial paralysis. The orbits were soft on retropulsion and no facial asymmetry was noted. The mean exophthalmolmetry reading measured 12.6 (SD 1.1) mm. The lagophthalmos varied from 1-5 mm. One patient (one eye) with 3 mm lagophthalmos developed a corneal ulcer and was treated with topical antibiotics and gold weight placement in the upper eyelid.

CONCLUSION

Enophthalmic patients with deep superior sulci and retro-placed upper eyelids may present with lagophthalmos and exposure keratopathy.

[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.

The silent sinus syndrome: a case series and literature review

PURPOSE

The purpose of this study is to describe the clinical and pathologic features of a form of chronic maxillary atelectasis referred to as the silent sinus syndrome, which is characterized by progressive enophthalmos secondary to maxillary collapse resulting from maxillary sinus hypoventilation.

METHODS

A retrospective medical record analysis was carried out to identify patients with enophthalmos secondary to maxillary collapse. Clinical records, including ophthalmology and otolaryngology evaluations as well as computed tomography scans and operative reports, were carefully examined. A complete literature review for relevant studies was performed to examine possible pathophysiology and similar cases.

RESULTS

Four patients with enophthalmos and asymptomatic maxillary sinus disease were identified. On computed tomography, all four of the patients had opacified, partially collapsed maxillary sinuses with osteopenia of the sinus walls and orbital floor displacement resulting in enophthalmos. All four underwent successful functional endoscopic sinus surgery and transconjunctival orbital floor repair.

CONCLUSION

In some instances, chronic maxillary atelectasis can present with enophthalmos secondary to collapse of the maxillary sinus. For reasons that are unclear, the sinus component of the disease remains asymptomatic and is discovered only after thorough evaluation of the enophthalmos.

Relationship between the extent of fracture and the degree of enophthalmos in isolated blowout fractures of the medial orbital wall

PURPOSE

This study investigated the relationship between the extent of fracture and enophthalmos in blowout fractures of the medial orbital wall.

PATIENTS AND METHODS

Nine patients with isolated blowout fractures of the medial orbital wall, confirmed by computed tomography scans, were evaluated. The area of fracture and the volume of herniated orbital tissue were determined from computed tomography scans using simple linear measurements. Each of the calculated values for area and volume were compared with the degree of enophthalmos to determine whether there was any significant relationship between them.

RESULTS

Enophthalmos increased proportionally as the area of fracture or the volume of herniated orbital tissue increased (P < .05). The area of fracture and the volume of herniated orbital tissue associated with 2 mm of enophthalmos were 1.9 cm2 and 0.9 mL, respectively, as calculated from the regression curve.

CONCLUSION

Enophthalmos of 2 mm or more, which is a frequent indication for surgery, can be expected when the area of fracture is 1.9 cm2 or more, or the volume of herniated orbital tissue is 0.9 mL or more.

Maxillary sinus atelectasis with enophthalmos

Chronic maxillary sinusitis may present as atelectasis of the sinus with changes to surrounding structures. Several mechanisms have been proposed for this problem. Chronic obstruction of the sinus ostium, with resultant retention of secretions and osteitic bone resorption, may account for these changes. Enophthalmos is one manifestation that may require corrective treatment. Titanium micromesh reconstruction of the orbital floor, with or without onlay concha cartilage, has reliably resolved the enophthalmos. Reconstruction of the orbital floor and ventilation of the obstructed sinus ostium may be carried out relatively safely in a single operation. The standard endoscopic technique of uncinate removal and middle meatal antrostomy should be modified to prevent orbital penetration. This report reviews our series of 6 patients with this problem, as well as a comprehensive review of the literature. Recommendations for management of both the obstruction and the secondary orbital manifestations are presented.

Anatomy, pathophysiology, and prevention of senile enophthalmia and associated herniated lower eyelid fat pads

We describe in detail the anatomy and function of the "Lockwood suspensory ligament" and the interrelated function of the orbital contents responsible for the intraorbital position of the eyeball and fat. With age, or because of genetic disposition, the eyeball descends, reducing the space between it and the floor of the orbit. This will inevitably cause forward projection of the extraconical orbital fat, creating herniated fat pads and resulting in enophthalmia. Based on the volume of the bony orbit and its contents, it is likely that relocating, rather then removing, herniated fat pads will greatly improve and prevent the enophthalmia of aging and give the globe a position and a projection of youth. Based on the results of surgery using the capsulopalpebral flap, it is likely that a descended Lockwood suspensory ligament, rather than a weakened orbital septum, is the cause of herniated fat pads and enophthalmia. We feel neither a weakened orbital septum nor an overabundance of orbital fat nor a shallow orbit is responsible for either of these conditions. We give a detailed description of how to raise the globe, preserve and relocate herniated fat pads, and manage and prevent enophthalmia and obtain a beautiful, youthful looking eye.

Displacements of eyeball in orbital blowout fractures

Thirty-two cases of orbital blowout fracture, excluding those of linear fracture with trap-door variety, were selected to study the changes of the eyeball position: posterior displacement or enophthalmos, medial and inferior displacement. Two-millimeter slices of computed tomographic scans were taken, and the eyeball positions were measured with the contralateral eye as a control. Intraorbital edema, if present, at least 10 days after injury had little effect on the position of the eyeball, nor was there any evidence to suggest the late onset of enophthalmos. Enophthalmos remains around 1 mm before total orbital enlargement reaches 2 ml in volume, thereafter increases proportionally with total orbital enlargement until 4 ml, then remains on a plateau. Enophthalmos increases proportionally with the increase of medial orbital wall enlargement when the inferior orbital wall enlargement is less than 2 ml. With inferior wall enlargement more than 2 ml, 3 to 4 mm of enophthalmos is seen irrespective of the increase of medial wall enlargement. The medial displacement of the eyeball increases proportionally with the increase of medial wall enlargement when inferior wall enlargement is less than 2 ml. The inferior displacement of the eyeball has little proportional relationship with medial or inferior wall enlargement when the former exceeds 2 ml. Relatively good proportional relationship is found between the enophthalmos and the medial displacement of the eyeball, but not between the enophthalmos and the inferior displacement of the eyeball.

Unilateral enophthalmos secondary to acquired hemilipodystrophy

PURPOSE

To report a case of acquired hemilipodystrophy with ipsilateral enophthalmos.

METHODS

Case report. We examined a 25-year-old woman who developed progressive unilateral enophthalmos secondary to fat atrophy on the corresponding left side of her body.

RESULTS

Computed tomography confirmed that atrophy in the left orbit, loss of fat in the preorbital area, and partial loss of eyebrow cilia on the same side were present. A biopsy specimen from the left arm was consistent with lipodystrophy. The systemic examination and laboratory values were within normal limits.

CONCLUSION

Although it is a rare condition, lipodystrophy may be a cause of unilateral enophthalmos.

[Enophthalmos caused by orbital metastasis of breast carcinoma]

BACKGROUND

Orbital metastatic disease usually leads to exophthalmos but rarely to enophthalmos. We report a case of a metastasis causing enophthalmos.

PATIENT

A 68-year-old woman had mastectomy for breast cancer six years prior to presentation. She complained of double vision when looking sideways. The right eye showed a motility reduction in all directions and a slight ptosis. She had 4 mm enophthalmos, and the eyelids were sunk into the orbit. There were no signs of optic nerve damage. Magnetic resonance imaging showed a retrobulbar mass surrounding the optic nerve and infiltrating the muscles. The space of the orbital fat was reduced. A biopsy confirmed the diagnosis of metastatic breast carcinoma. Histologically, the connective tissue was infiltrated by lymphocytes, and the nuclei of the tumor cells where aligned in a linear "indian file" pattern. 30% of the tumor cells contained the estrogen-receptor protein, 40% the progesterone-receptor protein. The CA-15/3 and CEA levels were elevated. The patient underwent orbital radiation with 50 Gy. During the following 2 months, the enophthalmos increased to 6 mm.

DISCUSSION

We suggest the following hypothesis as the cause of enophthalmos in orbital metastases: The tumor growth goes along with fibrosis. Subsequent shrinkage of the connective tissue pulls the eye back into the orbit. The ensuing elevation of tissue pressure leads to atrophy of the retrobulbar fat. The increase of tumor volume is too slow to compensate for the fat atrophy. Slowly progressive enophthalmos with reduced motility is nearly pathognomonic of metastatic scirrhous breast carcinoma. In rare cases, a diffusely infiltrating carcinoma of the gastrointestinal tract may cause a similar picture.

[Resorbable synthetics (PDS foils) for bridging extensive orbital wall defects in an animal experiment comparison]

In a long term animal study (min 2 weeks; max 48 weeks) on 6 minipigs, clinical related defects of the medial orbital wall extending in the orbital roof (2.5 cm x 3.5 cm) were created. The defects were bridged by slowly resorbable polydioxanon implants (so called PDS-foils, Ethicon) of different thickness (0.25/0.50 mm) and compared to control defects of identical size. The histological findings reveal: 1. After 29 weeks the resorption of both PDS-implants had been completely finished. Only the morphological intact implants had osteoconductive capabilities. 2. The osseous regeneration of the orbital defects started from the osteotomized margins of the orbital wall. The regenerates were covered by unaffected mucosa. 3. The bony regeneration was supported by the activated periosteal membrane. 4. The resorbed PDS-implants were being replaced by a tight scar tissue, which did not had any adjection to the orbital content. 5. The control defects showed a prolapse of the soft tissue with resulting enophthalmos. 6. According to the material specific characteristics, PDS-foils allow a sufficient bridging of even great and anatomically demanding orbital defects. 7. Notice: The hydrolytical broken down implant material may produce an irritation of the surrounding tissue causing a foreign body granuloma.

[Orbital volumetry as a planning principle for reconstruction of the orbital wall]

Before reconstruction of the orbital walls and other surgical procedures concerning the orbits leading to a modification of pathologically altered orbital volumes, it is useful to measure these volumes in order to allow preciser correction. Orbital volumetric studies on 22 patients and 6 dry skulls were performed using high resolution computer tomography. 14 patients presented enophthalmos of various origin, 3 patients fibrous dysplasia involving the orbits and 5 patients showed no orbital pathology. In 10 patients with unilateral posttraumatic 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 orbital enlargement, followed by a change in soft-tissue shape and position is the usual cause for posttraumatic enophthalmos. Changes in volume of soft-tissues themselves are less significant.

Measurement of globe position in complex orbital fractures. II. Patient evaluation utilizing a modified exophthalmometer

Globe position was assessed by both the Hertel exophthalmometer and the modified external auditory canal (EAC)-fixated device in 27 patients with complex orbital fractures (18 tripod and 9 Le Fort fractures). Although 94% of the patients with tripod fractures had relative exophthalmos on the fracture side or no difference between eyes by Hertel exophthalmometry, greater than 30% of the same patients showed relative enophthalmos when measured by the EAC-fixated device. In three of four patients undergoing surgical repair of the orbital floor, modified exophthalmometry showed exophthalmos of greater than or equal to 2 mm postoperatively on the fractured side. The relatively low incidence of enophthalmos in tripod fractures indicates a need for selective orbital floor repair; the uniform exploration of the orbital floor should be discouraged. Multiple comminuted facial fractures (Le Fort II and III) showed a greater variability in globe position and a high frequency (90%) of enophthalmos, suggesting a need for early orbital repair in these patients. EAC-fixated exophthalmometry can provide meaningful information regarding globe position in orbitofacial fracture patients in which orbital rim-based methods are precluded.

Congenital unilateral fibrosis, blepharoptosis, and enophthalmos syndrome

The authors report four cases of the rarest form of the congenital fibrosis syndrome. This disorder is exhibited in infancy as unilateral blepharoptosis, strabismus, limited ductions, globe displacement (enophthalmos and blepharoptosis), and decreased vision, usually due to amblyopia. Forced ductions are positive and surgical exploration confirms anomalous muscle structure. Computed tomography and magnetic resonance imaging studies in these four patients were diagnostically beneficial, showing extraocular muscle and tendinous insertion involvement, and poorly defined intraconal and extraconal masses that had the appearance of scar or inflammatory tissue. All patients had globe displacement. The opposite eye and intracranial contents were normal in all of our patients. Results of histopathologic examination obtained at surgery in three of these patients show replacement of affected structures by fibrous tissue and included the extraocular muscles, orbital fat, Tenon's capsule, and conjunctiva.

Use of Vicryl (polyglactin-910) mesh implant for correcting enophthalmos and hypo-ophthalmos. A study of 16 patients

Vicryl mesh (polyglactin-910) implants were used to reconstruct the orbital floor to correct enophthalmos or hypo-ophthalmos (globe ptosis) in 16 patients. The main advantages of Vicryl mesh over other alloplastic implants is that (a) it is absorbed by host tissue, and, once absorbed, it will not cause long-term complications; (b) it is layered and is cut from folded sheets into the appropriate size, shape, and thickness for the treatment of enophthalmos or hypo-ophthalmos; and (c) it is soft and pliable and, therefore, is unlikely to erode orbital structures. We followed all patients for a minimum period of 6 months after surgery and observed no significant adverse reactions to the mesh; 15 of the patients had good surgical results with a mean improvement of 1.4 mm in enophthalmos and 0.6 mm in hypo-ophthalmos. After surgery, one patient with combined medial wall and floor fractures developed enophthalmos that was 2 mm more severe than the degree of preoperative enophthalmos. Vicryl mesh should be considered an alternative to both nonautogenous implants and autogenous grafts in orbital floor fracture repair especially for correction of mild and possibly moderate degrees of enophthalmos and hypo-ophthalmos.

Horner's syndrome in the horse: a clinical, experimental and morphological study

A clinical case of Horner's syndrome is described in a Standardbred horse, and the various symptoms of cranial sympathetic denervation are studied in two ponies after experimental transection of the left cervical sympathetic trunk and vagosympathetic trunk, respectively. The most prominent symptoms of equine Horner's syndrome were ptosis, local sweating and increased cutaneous temperature in the denervated area. Enophthalmos, miosis and increased lacrimation were also observed but these symptoms were mild, variable and difficult to ascertain. Prolapse of the third eyelid was not noticed. Concomitant laryngeal hemiplegia was present in the clinical case and was provoked experimentally in one pony by transection of the left vagosympathetic trunk. The aetiology of each of these symptoms is discussed by comparing the results of pharmacological tests and histological findings in the three horses with the data from the literature.

Clinical and ultrastructural studies of Romberg's hemifacial atrophy

Romberg's disease is an uncommon and poorly understood condition manifested by progressive hemifacial atrophy of skin, soft tissue, and bone. In order to better define the natural history and anatomic variation of this disorder, we evaluated 41 patients by history, physical examination, and facial radiographs. Light microscopic studies were performed on tissue from 19 patients, and ultrastructural analysis was performed on specimens from 6 patients. The average age at inception of the disease was 8.8 years. Atrophy, within one or more trigeminal nerve dermatomes, progressed at a variable rate (mean period of active tissue dissolution = 8.9 +/- 6 years). In 26 patients with skeletal involvement, the mean age of onset was 5.4 years, versus 15.4 years for 15 patients without skeletal involvement, a statistically significant difference (p less than 0.01). However, there was no correlation between the severity of soft-tissue deformity and the age of onset. Electron microscopy demonstrated lymphocytic infiltrates in neurovascular bundles and abnormalities of vascular endothelium and basement membranes. We hypothesize that the pathogenesis of Romberg's disease involves chronic cell-mediated vascular injury and incomplete endothelial regeneration along branches of the trigeminal nerve (lymphocytic neurovasculitis).