Deep Lateral Wall Partial Rim-Sparing Orbital Decompression with Ultrasonic Bone Removal for Treatment of Thyroid-Related Orbitopathy

Influence of orbital decompression on upper eyelid retraction in Graves' orbitopathy: a systematic review and meta-analysis

Graves'-associated upper eyelid retraction (GAUER) is the commonest manifestation of orbitopathy in adults. Surgical management typically follows a 3-step staged approach commencing with orbital decompression. The rationale behind this is that certain surgical interventions can influence the parameters and outcomes of subsequent procedures. We performed a systematic review and meta-analysis evaluating the effects of orbital decompression on GAUER in adult patients with Graves' orbitopathy. All original English, non-pediatric studies meeting the study inclusion criteria from the last 20 years were included. The characteristics of margin reflex distance 1 (MRD-1) pre- and post-orbital decompression of 688 orbits were collected, and a meta-analysis of 472 orbits was performed. The average reduction in MRD-1 across 688 orbits was found to be 0.40 mm. Meta-analysis of 6 applicable articles demonstrated that orbital decompression decreases MRD-1 by an average of 0.35 mm (n = 472, p = .007, 95% CI = [0.08, 0.63]). This study demonstrates that although statistically significant, orbital decompression does not appear to have a clinically significant effect on GAUER. This has implications for clinical practice, namely the likely requirement of eyelid surgery following or in combination with orbital decompression, and the importance of counselling patients on this preoperatively.

Superior orbital fissure syndrome after deep lateral orbital wall decompression in Graves' ophthalmopathy

PURPOSE

The superior orbital fissure contains cranial nerves III, IV, VI, and V1 with their three branches: frontal, lacrimal, and nasociliary. Superior orbital fissure syndrome (SOFS) is rare and can occur as a result of compression of these nerves due to trauma, bleeding, or inflammation in the retrobulbar space, but no cases of SOFS after deep lateral orbital wall decompression (DLOWD) have been reported. The aim of this paper is to describe this pathology, its possible causes, management, and outcome.

METHODS

Retrospective study of 575 DLOWD in patients with disfiguring exophthalmos due to Graves' ophthalmopathy performed in our hospital between 2010 and 2023. Three cases of postoperative SOFS were identified based on clinical presentation, history, physical examination, and radiological study. All patients were observed for a minimum of 12 months.

RESULTS

SOFS was diagnosed with the presence of ophthalmoplegia, ptosis, fixed and dilated pupils, hypo/anesthesia of the upper eyelid and forehead, loss of corneal reflex, and no loss of vision after DLOWD. Fractures, edema, and hemorrhages were excluded. They were treated with high-dose intravenous steroids and the patients recovered completely.

CONCLUSIONS

DLOWD challenges orbital surgeons because it requires removing bones near the globe or neurovascular structures. SOFS may occur due to the proximity and increased pressure on these structures.

Biomechanical analysis of fixation methods for bone flap repositioning after lateral orbitotomy approach: A finite element analysis

OBJECTIVE

In ophthalmic surgery, different materials and fixation methods are employed for bone flap repositioning after lateral orbitotomy approach (LOA), yet there is no unified standard. This study aims to investigate the impact of different fixation strategies on orbital stability through Finite Element Analysis (FEA) simulations of the biomechanical environment for orbital rim fixation in LOA.

METHODS

A Finite Element Model (FEM) was established and validated to simulate the mechanical responses under various loads in conventional lateral orbitotomy approach (CLOA) and deep lateral orbital decompression (DLOD) using single titanium plate, double titanium plates, and double absorbable plates fixation methods. The simulations were then validated against clinical cases.

RESULTS

Under similar conditions, the maximum equivalent stress (MES) on titanium alloy fixations was greater than that on absorbable plate materials. Both under static and physiological conditions, all FEM groups ensured structural stability of the system, with material stresses remaining within safe ranges. Compared to CLOA, DLOD, which involves the removal of the lateral orbital wall, altered stress conduction, resulting in an increase of MES and maximum total deformation (MTD) by 1.96 and 2.62 times, respectively. Under a horizontal load of 50 N, the MES in FEM/DLOD exceeded the material's own strength, with an increase in MES and MTD by 3.18 and 6.64 times, respectively, compared to FEM/CLOA. Under a vertical force of 50 N, the MES sustained by each FEM was within safe limits. Bone flap rotation angles remained minimally varied across scenarios. During follow-up, the 12 patients validated in this study did not experience complications related to the internal fixation devices.

CONCLUSION

Under static or physiological conditions, various fixation methods can effectively maintain stability at the orbitotomy site, and absorbable materials, with their smoother stress transmission properties, are more suited for application in CLOA. Among titanium plate fixations, single titanium plates can better withstand vertical stress, while double titanium plates are more capable of handling horizontal stress. Given the change in the orbital mechanical behavior due to DLOD, enhanced fixation strength should be considered for bone flap repositioning.

Update on the surgical management of Graves' orbitopathy

Graves' orbitopathy (GO) is a complex autoimmune disorder of the orbit that causes the eye to appear disfigured. GO is typically associated with Graves' disease, an inflammatory autoimmune condition that is caused by thyrotropin receptor autoantibodies. Although our knowledge of the pathophysiology of GO has improved, its exact pathogenesis remains unclear. Some patients suffer from disfigurement, double vision, and even vision loss rather than hyperthyroidism. The disease severity and activity prompt different treatments, as the signs of GO are heterogeneous, so their management can be very complex. Despite medical advances, the first-line treatment for moderate-to-severe active GO is still glucocorticoids, while surgery can be critical for the treatment of chronic inactive GO. Surgery is sometimes required in the acute phase of the disease when there is an immediate risk to vision, such as in dysthyroid optic neuropathy. Most surgeries for GO are rehabilitative and subdivided into three categories: decompression, strabismus repair, and lid surgery. This review is a basic overview of the field, with up-to-date knowledge of the surgical techniques for GO. We review and summarize recent literature on the advances in surgery for GO to provide up-to-date insights on the optimal surgical treatment for GO.

Endoscopic Transconjunctival Deep Lateral Wall Decompression for Thyroid-associated Orbitopathy: A Minimally Invasive Alternative: Transconjunctival Endoscopic with Wall Decompression for TAO

PURPOSE

To investigate the feasibility, efficacy, and safety of endoscopic transconjunctival transorbital deep lateral wall decompression for thyroid-associated orbitopathy (TAO).

DESIGN

Prospective single-surgeon interventional case series.

METHODS

Twenty-two patients (39 orbits) diagnosed with thyroid-associated orbitopathy without dysthyroid optic neuropathy were enrolled in this study. All patients underwent endoscopic transconjunctival transorbital deep lateral wall decompression for proptosis reduction. The data, including measurement on exophthalmometry, volumetric change on computed tomography, and surgery-related complications, were analyzed.

RESULTS

We observed a proptosis reduction (mean, 3.42 ± 0.87 mm; range, 2.10-5.52 mm) and a corresponding decrease in the bony volume of the greater wing of the sphenoid bone (mean, 1.89 ± 0.81 cm³; range, 0.56-3.79 cm³) postoperatively. Preexisting diplopia improved in 5 patients (22.73%). Transient zygomaticotemporal hypoesthesia developed in all patients, and cerebrospinal fluid leakage occurred in 1 orbit (2.56%). No patient complained of temporal hollowing, oscillopsia, or new-onset or worsening diplopia during follow-up.

CONCLUSIONS

Endoscopic transconjunctival transorbital deep lateral wall decompression is an effective and minimally invasive treatment for proptosis reduction in patients with thyroid-associated orbitopathy. The surgery-related complications with this technique were fewer compared with traditional approaches.

Orbital Solitary Fibrous Tumor: Four Case Reports-Clinical and Histopathological Features

PURPOSE

To retrospectively describe the clinical characteristics, management, and outcomes of four cases of orbital solitary fibrous tumor (SFT). In one patient, we present an ultrasonic aspirator system for tumor removal.

METHODS

Four patients with orbital SFT were selected: one patient with orbital SFT, another patient with frontal and ethmoidal SFT and orbital affectation with high rates of recurrence, the third patient with frontal lobe SFT and orbital invasion with multiple recurrences, and the fourth case with a history of craniopharyngioma surgery and SFT located on the orbital apex.

RESULTS

All cases showed proptosis, eye movement restriction, and, in three cases, visual acuity alteration. Different treatments were applied: in three cases, excision was performed, one of them with an ultrasonic aspirator system, and in the remaining case, an exenteration was done (in two cases, radiosurgery treatment was also applied). The immunohistochemical study revealed SFT, similar to hemangiopericytomas (HPCs). No recurrence has been observed after surgical treatment.

CONCLUSION

The SFT is a spectrum of different tumors with similar histopathological characteristics. The use of immunohistochemical markers is very helpful in the diagnosis. The main problem of orbital involvement is the risk of damaging important structures adjacent to the tumor during the surgical removal. The ultrasonic aspirator system allows elimination of the tumor without damaging other orbital structures.

Surgical removal of orbital tumors by orbital approach using ultrasonic surgical system SONOPET®

Purpose: Orbital tumor surgery can be challenging when the tumor is located in a very narrow surgical field and close to important structures, such as nerves or extraocular muscles that can be damaged during surgery. Advances in technology and special surgical techniques help to avoid such damage. We describe our experience using SONOPET® ultrasonic surgical aspirator to remove 12 different orbital tumors that were difficult to treat due to their poorly defined borders, adhesions, or location.Methods: This is a retrospective case series that describes 12 operations that occurred between March 2016 to December 2018 using an ultrasonic device to debulk or remove orbital tumors. Different approaches and handpieces were used for each case depending on the location and consistency of the tumor.Results: All patients experienced an improvement in preoperative signs and symptoms, pain, proptosis, diplopia, or lagophthalmos. Visual acuity, which had been reduced due to the tumor, was also recovered. There were no intraoperative or postoperative complications due to the use of the device.Conclusions: The ultrasonic aspirator is a safe, useful device that can successfully remove or debulk infiltrating orbital masses through any orbital access, regardless of their consistency. It is helpful in cases of difficult anatomical access or difficult extraction due to size or adhesions to the surrounding tissues.

Deep lateral orbital decompression for Graves orbitopathy: a systematic review

PURPOSE

To systematically review the literature on the deep lateral orbital decompression (DLD).

METHODS

The authors searched the MEDLINE, Lilac, Scopus, and EMBASE databases for all articles in English, Spanish, and French that used as keywords the terms orbital decompression and lateral wall. Two articles in German were also included. Data retrieved included the number of patients and orbits operated, types of the approach employed, exophthalmometric and horizontal eye position changes, and complications. The 95% confidence intervals (CI) of the mean Hertel changes induced by the surgery were calculated from series with 15 or more data.

RESULTS

Of the 204 publications initially retrieved, 131 were included. Detailed surgical techniques were analyzed from 59 articles representing 4559 procedures of 2705 patients. In 45.8% of the reports, the orbits were decompressed ab-interno. Ab-externo and rim-off techniques were used in 25.4% and 28.8% of the orbits, respectively. Mean and 95% CI intervals of Hertel changes, pooled from 15 articles, indicate that the effect of the surgery is not related to the technique and ranges from 2.5 to 4.5 mm. The rate of new onset of diplopia varied from zero to 8.6%. Several complications have been reported including dry eye, oscillopsia, temporal howling, lateral rectus damage, and bleeding. Unilateral amaurosis and subdural hematoma have been described in only one patients each.

CONCLUSIONS

The low rate of new-onset diplopia is the main benefit of DLD. Prospective studies are needed to compare the rate of complications induced by the 3 main surgical techniques used.

Orbital anatomical parameters affecting outcome of deep lateral orbital wall decompression

PURPOSE

To determine orbital anatomical parameters that affect surgical outcome of deep lateral orbital wall decompression.

METHODS

Twenty orbits of 20 patients with moderate proptosis (maximum 25 mm) due to thyroid eye disease who were stable for at least 6 months were included in this prospective cohort study. Four parameters including lateral orbital wall distance (LOWD), removable surface area (RSA), removable surface length (RSL), and sphenoid door jamb thickness (SDJ) were evaluated by computed tomography (CT) scan prior to surgery in these patients. Deep lateral orbital wall decompression without fat removal was done in all patients. Relationship between all these factors and proptosis reduction, 6 months after surgery was assessed.

RESULTS

Mean proptosis before decompression surgery (mean ± SD) was 23.22 ± 1.19 mm and reduction in Hertel exophthalmometry (mean ± SD) was -3.27 ± 1.03 mm (p = 0.006). Pearson correlation showed that LOWD, RSL, and SDJ had statistically significant correlation with proptosis reduction (p = 0.017, 0.002, and 0.001, respectively.). Linear multivariate regression analysis showed SDJ as the only independent factor in predicting surgical outcome.

CONCLUSION

several orbital anatomical factors have significant role in predicting surgical outcome following deep lateral wall orbital decompression. Among these parameters, SDJ is an independent factor, whereas LOWD and RSL are dependent factors. Preoperative assessment of the bony sphenoid anatomy may be helpful in predicting the amount of potential decompression.