Computed Tomography–Based Prediction of Exophthalmos Reduction After Deep Lateral Orbital Wall Decompression for Graves’ Orbitopathy

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.

Prediction of exophthalmos by body mass index for craniofacial reconstruction: consequences for cold cases

It is inconvenient for a forensic practitioner to gather population-specific data before performing a facial reconstruction. The inconvenience may defeat the point of creating the reconstruction. The objective of this study was to evaluate a non-population-dependent method of determining exophthalmos. The protrusion of the eyeball is known to vary with the contents of the orbital cavity based on bony orbital resorption or increased or decreased fat contents, as well as according to relative eyeball size. Of use are available statistics on body mass index, and this is discussed within the context of eyeball protrusion. A weak positive correlation (0.3263) between the body mass index of the country where the study originated, and the degree of exophthalmos was found. The results suggest that eyeball protrusion rates can be established according to body mass index, and this framework may be more useful considering conventional police practices.

Predictive markers for anti-inflammatory treatment response in thyroid eye disease

Anti-inflammatory treatment is the primary and vital therapeutic approach for active, moderate-to-severe thyroid eye disease (TED). Accurate pretreatment prediction of treatment response is of paramount importance for the prognosis of patients. However, relying solely on the clinical activity score asa determinant of activity has led to unsatisfactory treatment outcomes. In recent years, significant advancements have been made in identifying predictive markers for anti-inflammatory treatment response in TED, clinical markers, body fluid biomarkers and imaging biomarkers. Several clinical studies have developed prediction models based on these markers. However, there is still a lack of comprehensive elucidation or comparison between the different markers. Therefore, this review aims to provide a detailed analysis of the definition, characteristics, and application of predictive markers for anti-inflammatory treatment response in TED. Through detailed literature search, 26 articles applying anti-inflammatory treatment effect prediction with a total of 1948 TED patients were used for analysis and discussion. By gaining a better understanding of the current research on predictive markers, we can accelerate and guide the exploration of treatment prediction strategies, leading us towards an era of precise therapy for TED.

Endoscope-navigation-assisted orbital decompression for graves' orbitopathy

PURPOSE

To compare the surgical outcomes of endoscope-navigation (EN)-assisted orbital decompression and non-EN-assisted orbital decompression for Graves' orbitopathy (GO) and to assess the potential clinical advantage of EN in orbital decompression surgery.

METHODS

This retrospective cohort study was performed on 227 orbits of 147 GO patients who underwent EN-assisted orbital decompression (185 orbits) or non-EN-assisted orbital decompression (42 orbits). Assessment included proptosis reduction, best-corrected visual acuity (BCVA), diplopia, ocular restriction and surgical complications.

RESULTS

The proptosis reduction in the EN group was 0.9 mm greater than that in the non-EN group in the entire cohort (p  =  0.004) and 1.0 mm greater than that in the non-EN group in the propensity score matching cohort (p  =  0.025) at 2 years postoperatively. In all, 78.2% of orbits with sight-threatening GO in the EN group and 52.6% of orbits in the non-EN group showed BCVA improvement (p  =  0.026). The proportion of patients with improvement in diplopia was significantly greater in the EN group than in the non-EN group (p  =  0.026).

CONCLUSIONS

EN offers anatomical localization and deep-seated tissue visualization in orbital decompression and significantly improves the surgical outcomes for GO.

Risk prediction of dysthyroid optic neuropathy based on CT imaging features combined the bony orbit with the soft tissue structures

Purpose

To analyze computed tomographic (CT) imaging features of patients with dysthyroid optic neuropathy (DON) retrospectively and deduce a more appropriate predictive model.

Methods

The CT scans and medical records of 60 patients with clinically proven Graves' ophthalmopathy (GO) with (26 women and 10 men) and without DON (16 women and 8 men) were retrospectively reviewed, and 20 age- and sex-matched control participants (12 women and 8 men) were enrolled consecutively. The bony orbit [orbital rim angle (ORA), medial and lateral orbital wall angles (MWA and LWA), orbital apex angle (OAA), and length of the lateral orbital wall (LWL)], and the soft tissue structures [maximum extraocular muscle diameters (Max EOMD), muscle diameter index (MDI), medial and lateral rectus bulk from inter-zygomatic line (MRIZL and LRIZL), proptosis, intraorbital optic nerve stretching length (IONSL), superior ophthalmic vein diameter (SOVD), apical crowding, and presence of intracranial fat prolapse] were assessed on a clinical workstation. The CT features among groups were compared, and a multivariate logistic regression analysis was performed to evaluate the predictive features of DON.

Results

All bony orbital angle indicators, except ORA (p = 0.461), were statistically different among the three groups (all p < 0.05). The values of MWA, LWA, OAA, and LWL were larger in the orbits with the DON group than in the orbits without the DON group (all p < 0.05). The MDI, MRIZL, proptosis, IONSL, and SOVD were statistically significantly different among the three groups (all p < 0.05), in which the orbits with the DON group were significantly higher than the orbits without the DON group and control group. The apical crowding was more severe in the orbits with the DON group than in the orbits without the DON group (p = 0.000). There were no significant differences in the LRIZL and the presence of intracranial fat prolapse (all p > 0.05). The multivariate regression analysis showed that the MWA, MDI, and SOVD were the independent factors predictive of DON. The sensitivity and specificity for the presence of DON by combining these three indicators were 89 and 83%, respectively.

Conclusion

Bone and soft tissue CT features are useful in the risk prediction of DON, especially the MWA, MDI, and SOVD were the independent factors predictive of DON.

Different Characteristics of Orbital Soft Tissue Expansion in Graves Orbitopathy: Extraocular Muscle Expansion is Correlated to Disease Activity While Fat Tissue Volume With Duration

This study aimed to describe the correlation between some clinical features and orbital soft tissue volume in Graves orbitopathy (GO). The authors collected computed tomography scans from 56 untreated GO patients and measured fat volume (FV), intraorbital and extraorbital FV (IFV, EFV), bony cavity volume (BV), and extraocular muscle volume (MV) of the 112 orbits by using Mimics software. The ratio of soft tissue volume and BV were used to eliminate the individual variations. Outcomes were compared among groups and were correlated with clinical data, including age, sex, clinical activity score, duration, serum TSH receptor antibody (TRAb) level, body mass index and smoking status. Multivariate linear regression showed that higher MV/BV is associated with higher CAS and TRAb level ( P< 0.001, 0.005, res p ectively). No relationship was found between MV/BV and duration, sex, age, and body mass index. IFV/BV was related to duration (β=0.138, 95% confidence interval: 0.076-0.201, P <0.001), and did not correlate to clinical activity. IFV and MV are positively associated with exophthalmometry ( P =0.009, <0.001, respectively), while orbital bony volume (BV) is negatively correlated with exophthalmometry ( P =0.025). Results suggested TRAb level can impact the severity of GO mainly by affecting extraocular muscle rather than fat tissue. MV of GO is associated with disease activity, whereas IFV is correlated with duration and increases over time.

Lateral Wall Implant as an Adjunct to Lateral Wall Orbital Decompression in Severe Thyroid Eye Disease

PURPOSE

To describe the use of a lateral wall implant as an adjunct in lateral orbital wall decompression in severe thyroid eye disease.

METHODS

This study is a retrospective review of 6 patients who underwent prior orbital decompression but had persistent proptosis. These patients underwent lateral wall decompression with adjunct lateral wall implant placement with a manually vaulted 0.6-mm polyethylene-coated titanium mesh implant. Data collection included: visual acuity, intraocular pressure, exophthalmometry, ocular motility, eyelid position, and complication rates.

RESULTS

Eight orbits in 6 patients underwent maximal lateral wall decompression and reconstruction using the polyethylene-coated titanium implant. Four males and 2 females were included with ages ranging from 25 to 73 years. Visual acuity improved an average of 2.4 lines (range 0-5 lines). Intraocular pressure improved an average of 7.5 mm Hg (2-13 mm Hg). There was reduction of proptosis by 3.4 mm on average (1-7 mm). Upper eyelid retraction improved on average by 1.8 mm (0-5 mm). Horizontal eye movements improved by 11% on average (-3.1% to +25%). Excellent cosmesis was achieved with no visible temple deformity, trismus, conjunctival scarring, orbital hemorrhage, or vision loss.

CONCLUSIONS

The amount of volume created in lateral wall decompression is limited by the amount of native bone present and the temporalis muscle. In severe or recalcitrant cases, the authors propose the placement of a lateral wall implant as an adjunct to laterally displace the temporalis muscle and create additional volume. This technique accomplishes further reduction of proptosis in patients who have undergone prior orbital decompression.

A randomized comparative study of inferomedial vs. balanced orbital decompression. Analysis of changes in orbital volume, eyelid parameters, and eyeball position

BACKGROUND/OBJECTIVES

The objective of this study is to investigate and compare changes in orbital volume, eyelid parameters, and eyeball position after inferomedial and balanced (medial + deep lateral walls) orbital decompression (OD) in patients with Graves' orbitopathy (GO).

SUBJECTS/METHODS

Prospective interventional trial. Forty-two patients with inactive GO and clinical indication for OD were randomly assigned to inferomedial or balanced OD. Preoperative and postoperative Hertel exophthalmometry, standardized photography, and computed tomography were used to evaluate upper and lower eyelid margin reflex distances (MRD₁ and MRD₂), orbital expansion, and changes in eyeball position.

RESULTS

Clinical and radiological exophthalmometry improved significantly after OD with both surgical techniques (p < 0.001), but more so with balanced OD (p = 0.02). Concurrent eyeball descent (p = 0.01) and orbital volume expansion (p < 0.001) were observed with both techniques. The mean decompression volume was similar for the medial wall and the lateral wall but significantly smaller for the inferior wall (p < 0.05). Significant correlation coefficients were found for Hertel reduction vs. total decompression volume (p < 0.05). In the multivariate linear analysis, lateral wall decompression volume (LWDV) was predictive of exophthalmos reduction (p < 0.05). The two techniques produced a similar reduction in MRD₁ and MRD₂. A significant correlation was also found between Hertel reduction and lower lid elevation (p < 0.05).

CONCLUSIONS

Both inferomedial and balanced OD successfully expanded orbit capacity, but the latter was more efficient at reducing exophthalmos probably due to the inclusion of the lateral wall. Upper and lower eyelid retraction improved after OD, but only lower eyelid elevation was correlated with exophthalmos reduction.

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.

Comparison of the decompressive effect of different surgical procedures for dysthyroid optic neuropathy using 3D printed models

PURPOSE

To compare the decompressive effect around the optic nerve canal among 3 different decompression procedures (medial, balanced, and inferomedial) using 3D printed models.

METHODS

In this experimental study, based on data obtained from 9 patients (18 sides) with dysthyroid optic neuropathy, a preoperative control model and 3 plaster decompression models were created using a 3D printer (total, 72 sides of 36 models). A pressure sensor was placed at the optic foramen, and the orbital space was filled with silicone. The surface of the silicone was pushed down directly, and changes in pressure were recorded at 2-mm increments of pushing.

RESULTS

At 10 mm of pushing, there was significantly lower pressure in the medial (19,782.2 ± 4319.9 Pa, P = 0.001), balanced (19,448.3 ± 3767.4 Pa, P = 0.003), and inferomedial (15,855.8 ± 4000.7 Pa, P < 0.001) decompression models than in the control model (25,217.8 ± 6087.5 Pa). Overall, the statistical results for each 2-mm push were similar among the models up to 10 mm of pushing (P < 0.050). At each push, inferomedial decompression caused the greatest reduction in pressure (P < 0.050), whereas there was no significant difference in pressure between the medial and balanced decompression models (P > 0.050).

CONCLUSION

All 3 commonly performed decompression procedures significantly reduced retrobulbar pressure. Because inferomedial decompression models obtained the greatest reduction in pressure on the optic nerve canal, inferomedial decompression should be considered the most reliable procedure for rescuing vision in dysthyroid optic neuropathy.

Extraocular muscle expansion after deep lateral orbital wall decompression: influence on proptosis reduction and its predictive factors

PURPOSE

To examine the relationship between extraocular muscle expansion and proptosis reduction (Δproptosis) in patients with thyroid eye disease who underwent deep lateral orbital wall decompression and to analyze the factors that contribute to extraocular muscle expansion.

METHODS

This retrospective, observational study included 133 sides from 77 patients with thyroid eye disease. The cross-sectional areas of the greater wing of the sphenoid bone (trigone), extraocular muscles, and superior ophthalmic vein were measured on computed tomographic images. Variables influencing Δproptosis were analyzed using multivariate linear regression analyses with stepwise variable selection. Predictive factors for the rate of postoperative increase in the cross-sectional extraocular muscle areas (Δextraocular muscle) were analyzed using the same statistical method.

RESULTS

The amount of orbital fat removed (P < 0.001) and rate of Δlateral rectus muscle (P < 0.001) were positively and negatively correlated with Δproptosis, respectively (r = 0.425; adjusted r² = 0.168; P < 0.001). The cross-sectional trigone area (P < 0.001) was positively correlated with the rate of Δlateral rectus muscle, whereas the preoperative cross-sectional lateral rectus muscle area (P < 0.001) and amount of orbital fat removed (P = 0.036) were negatively correlated with the rate of Δlateral rectus muscle (r = 0.551; adjusted r² = 0.288; P < 0.001).

CONCLUSION

Lateral rectus muscle expansion was negatively correlated with proptosis reduction and proved to be predictable before surgery. The results of this study will help predict proptosis reduction after deep lateral orbital wall decompression and to preoperatively plan additional orbital bony and fat decompression.

Changes in Field of Binocular Single Vision and Ocular Deviation Angle After Balanced Orbital Decompression in Thyroid Eye Disease

PURPOSE

To evaluate influential factors for changes in the binocular single vision (BSV) and ocular deviation angle in the medial direction after bilateral balanced orbital decompression in thyroid eye disease.

METHODS

This retrospective study included 41 patients. The areas of BSV and the angles of medial ocular deviation on the Hess chart were measured. The percentages of pre- and postoperative areas against the normal area (%BSV) and the change in BSV after surgery were calculated. Postoperative change in the angle was calculated by subtraction of the preoperative angle from the postoperative one. Influential factors for the change in BSV and that in the medial deviation angle were evaluated via multivariate linear regression analysis.

RESULTS

The maximum cross-sectional area of the medial rectus muscle, preoperative %BSV, and preoperative medial ocular deviation angle were significant factors of change in BSV (adjusted r2 = 0.449, p < 0.001), although age, history of anti-inflammatory treatment, volume of removed orbital fat, findings on CT images, maximum cross-sectional areas of the other rectus muscles, and presence or absence of a periosteal flap did not affect change in BSV (p > 0.050). On the contrary, all variables did not influence postoperative changes in the medial ocular deviation angle (p > 0.050).

CONCLUSIONS

In balanced orbital decompression, the maximum cross-sectional area of medial rectus muscle, preoperative field of BSV, and medial ocular deviation were significant influential factors for postoperative changes in field of BSV.

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.