Levator Muscle Enlargement in Thyroid Eye Disease-Related Upper Eyelid Retraction

Lateral Globe Exposure Associated With Graves Upper Eyelid Retraction: The Influence of the Superior Complex Enlargement and Proptosis

PURPOSE

To investigate the association of the lateral exposure of the globe with proptosis and the enlargement of the superior complex (SC) (levator palpebrae superioris muscle + superior rectus muscle) in patients with Graves upper eyelid retraction.

METHODS

Twenty-eight patients with upper lid retraction secondary to Graves orbitopathy and 28 controls matched by age and gender participated in the study. The variables exophthalmometry, margin-reflex distance 1, and upper lid fissure temporal and nasal areas were assessed. Coronal CT scans were evaluated for the measurement of the SC area. A 5% level of significance was assumed for analysis.

RESULTS

Abnormal temporal nasal area differences (T-N), defined as values above the superior limit of the control distribution (15.58mm2) were detected in 18 patients. Multiple regression analysis showed a significant correlation of abnormal temporo-nasal asymmetries with the SC area and the proptosis (T-N = -6.7 + 0.62* proptosis + 12.3 SC area, R2 = 0.37; p = 0.003).

CONCLUSION

The etiology of the enhanced lateral globe exposure is not unifactorial. SC enlargement and, to a lesser extent, proptosis are important factors correlated to lateral globe exposure.

Extraocular Muscle Enlargement in Thyroid Eye Disease Using Volumetric Analysis

BACKGROUND AND OBJECTIVES

It is commonly taught that thyroid eye disease (TED) causes enlargement of the extraocular muscles (EOMs) in the following descending order: inferior rectus (IR), medial rectus (MR), superior rectus (SR), lateral rectus (LR), superior oblique (SO) and inferior oblique (IO). However, with recent literature challenging this notion, we aimed to compare EOM volumes in our cohort of TED patients.  Methods: We conducted a retrospective, non-randomized case-control study. Twenty-eight orbits from 28 unique patients with TED who had high-resolution CT scans were compared to 31 normal orbits, all from a single academic institution. Orbital soft tissues were manually segmented using ITK-SNAP 3.8.0 (http://itksnap.org), and soft tissue volumes of the control and TED orbits were compared using independent-sample t-tests.

RESULTS

Of the TED orbits, 54% of SR/levator palpebrae superioris complex volumes (SRC) and 50% of IR volumes were greater than two standard deviations above the normal orbit average. Compared to controls, the mean SRC volume in TED subjects was 2.3 times enlarged, followed by the IR (2.1 times), SO (1.8 times), MR (1.7 times), LR (1.6 times), IO (1.6 times), and orbital fat (1.4 times) (p < 0.01 for all).  Conclusions: Our findings suggest that contrary to previous teaching, the SRC may be the most severely affected in TED.

Blink Lagophthalmos in Graves Orbitopathy

PURPOSE

To investigate the relationship between the kinematics of spontaneous blinks and the anterior area of the levator palpebrae superioris muscle in patients with Graves orbitopathy (GO).

METHODS

This is a case-control study. The authors measured the margin reflex distance of the upper eyelid (margin reflex distance 1), the kinematics of spontaneous blinks, and the anterior area of levator palpebrae superioris muscle in CT coronal scans of patients with Graves upper eyelid retraction (GO) and a control group. The eye with the greatest margin reflex distance 1 was selected for analysis in each group.

RESULTS

A total of 68 participants were included, with 36 in the GO group and 32 in the control group. In the GO group, the mean margin reflex distance 1 measured 6.5 mm, while in the control group, it was 3.9 mm. Almost all parameters related to the closing phase of spontaneous blinking activity, including amplitude, velocity, blinking rate, and interblink time, did not differ between the two groups. However, the effectiveness of the blink's amplitude (ratio of blink amplitude to margin reflex distance 1) and the main sequence (relationship between amplitude and velocity) were significantly reduced in the GO group compared with the control group. The area of the levator palpebrae superioris muscle was significantly larger in GO than in controls, with 71.4% of patients' muscles outside of the maximum range of the controls.

CONCLUSIONS

In patients with GO, there is a reduction in blinking effectiveness, also known as blink lagophthalmos, which is a factor in the common occurrence of ocular surface symptoms. The increase in velocity with amplitude is also reduced in GO.

Graves' Eye Disease: Clinical and Radiological Diagnosis

Graves' disease is an autoimmune disorder in which hyperthyroidism results in various systematic symptoms, with about 30% of patients presenting with Graves' eye disease (GED). The majority of patients with GED develop mild symptoms, including eyelid retraction, exposure of the globe, superior rectus-levator muscle complex inflammation, and fat expansion, leading to exophthalmos. More severe cases can result in extraocular muscle enlargement, restricted ocular movement, eyelid and conjunctival edema, and compression of the optic nerve leading to compressive optic neuropathy (CON). GED severity can be classified using the Clinical Activity Score, European Group on Graves' Orbitopathy scale, NO SPECS Classification system, and VISA system. CT and MRI aid in the diagnosis of GED through the demonstration of orbital pathology. Several recent studies have shown that MRI findings correlate with disease severity and can be used to evaluate CON. Mild cases of GED can be self-limiting, and patients often recover spontaneously within 2-5 years. When medical treatment is required, immunomodulators or radiotherapy can be used to limit immunologic damage. Surgery may be needed to improve patient comfort, preserve the orbit, and prevent vision loss from optic nerve compression or breakdown of the cornea.

Management of Thyroid Eye Disease: A Consensus Statement by the American Thyroid Association and the European Thyroid Association

Thyroid eye disease (TED) remains challenging for clinicians to evaluate and manage. Novel therapies have recently emerged, and their specific roles are still being determined. Most patients with TED develop eye manifestations while being treated for hyperthyroidism and under the care of endocrinologists. Endocrinologists, therefore, have a key role in diagnosis, initial management, and selection of patients who require referral to specialist care. Given that the need for guidance to endocrinologists charged with meeting the needs of patients with TED transcends national borders, and to maximize an international exchange of knowledge and practices, the American Thyroid Association and European Thyroid Association joined forces to produce this consensus statement.

Management of thyroid eye disease: a Consensus Statement by the American Thyroid Association and the European Thyroid Association

Thyroid eye disease (TED) remains challenging for clinicians to evaluate and manage. Novel therapies have recently emerged, and their specific roles are still being determined. Most patients with TED develop eye manifestations while being treated for hyperthyroidism and under the care of endocrinologists. Endocrinologists, therefore, have a key role in diagnosis, initial management, and selection of patients who require referral to specialist care. Given that the need for guidance to endocrinologists charged with meeting the needs of patients with TED transcends national borders, and to maximize an international exchange of knowledge and practices, the American Thyroid Association and European Thyroid Association joined forces to produce this Consensus Statement.

Müllerotomy with anterior graded Müller muscle disinsertion for Graves upper eyelid retraction: validation of surgical outcomes using Bézier curves

PURPOSE

To assess with Bézier curves the outcomes of Müllerotomy with anterior graded Müller muscle disinsertion for the treatment of Graves upper eyelid retraction (UER).

METHODS

Eighty-six eyelids of 52 inactive GO patients operated from November 2018 to June 2021 were included in this study. All measurements were performed on Bézier curves adjusted to the upper lid contour with a previously validated algorithm. Lid contour was classified regarding grade of superposition (GS) as excellent (GS > 90%), good (GS 85-90%) or poor (< 85%). Surgical success was defined as complete or partial if postoperative grade of asymmetry was < 10% with an excellent or good lid contour, respectively.

RESULTS

The mean age was 51 ± 10.4 years with a range from 31 to 78 years and a mean follow-up of 14.4 ± 7.4 months. There was a significant improvement of median GS (p < 0.0001) from preoperative (74.3%; 10.7 IQR) to postoperative values (91.7%; 6.3 IQR). A normalization of postoperative contour peak (- 0.69; 1.27 SD) and MPLD90 (4.2 mm; 0.8 SD) was noticed (p < 0.0001). Postoperative lid contour was excellent in 62 (72%), good in 16 (19%) and poor in 8 eyelids (9%). Surgical success was achieved in 42 patients (81%), from which 34 (81%) were complete. Reintervention was required in 14 eyelids (16%).

CONCLUSIONS

Measuring surgical outcomes with Bézier curves allows an automated, complete and objective assessment, giving more consistency to our data compared to previous reports. Müllerotomy with graded Müller muscle disinsertion is a safe and effective procedure for Graves UER, offering predictable results.

Extraocular muscle enlargement

Extraocular muscle enlargement can occur secondary to a range of orbital and systemic diseases. Although the most common cause of extraocular muscle enlargement is thyroid eye disease, a range of other inflammatory, infective, neoplastic, and vascular conditions can alter the size and shape of the extraocular muscles. Imaging with computed tomography and magnetic resonance imaging plays an essential role in the workup of these conditions. This article provides an image-rich review of the wide range of pathology that can cause enlargement of the extraocular muscles.

Management of eyelid retraction related to thyroid eye disease

Eyelid retraction related to thyroid eye disease (TED) is a challenging condition. It is one of the main clinical signs and a major diagnostic criterion in TED. This condition may threaten vision due to exposure keratopathy, in addition to its esthetic alterations, which may lead to psychosocial implications and affect the patient's quality of life. Although it is more commonly observed in the upper eyelid, it may be present on both the upper and lower lids. Numerous surgical and nonsurgical treatment modalities have been described and will be reviewed in this article. Management should be based on an individual patient assessment, taking into consideration the disease stage, severity, and clinician experience.

Upper Eyelid Contour Changes After Orbital Decompression in Graves Orbitopathy

PURPOSE

To evaluate the effect of orbital decompression on the upper eyelid contour.

METHODS

A paired cross-sectional analysis of the upper eyelid contour was performed for 103 eyes of 66 patients who underwent orbital decompression. A control group of 26 normal subjects was also included. The eyelid contour of all participants were measured with Bézier lines adjusted to the eyelid contour and 9 midpupil eyelid margin (MPD) distances from a horizontal line bisecting the pupil. One central, corresponding to the margin reflex distance (MRD 1), and 8 equally distributed medially and laterally at 20% of the interval between the lines. Patients were classified as with flare if the height of the most lateral MPD relative to the MRD 1 was above the upper limit of the controls.

RESULTS

Preoperatively 63 of the 103 contours were classified as flare + (F+). After decompression MRD1 showed a mean decrease of 0.4 mm and the location of the contour shifted 0.8 mm medially. These changes were not correlated with proptosis reduction. Orbital decompression decreased the lateral curvature of the contours especially for the F+ lids. In 40% of the F+ eyelids the flare sign disappeared after decompression.

CONCLUSIONS

Orbital decompression affects the lateral eyelid contour and diminishes the amount of lateral eyelid retraction surgery necessary to correct the flare sign. In 40% of the patients, the eyelid contour is normalized with proptosis reduction only.

Extrathyroidal Manifestations of Thyroid Disease: Graves Eye Disease

Graves disease is an autoimmune disorder caused by the breakdown of immune tolerance to thyroid antigens against the TSH receptor. In approximately 25% of patients, an inflammatory condition, Graves eye disease (GED), affects the orbital soft tissues. About 60% of patients develop mild symptoms including fat expansion and inflammation of the levator muscle complex with resultant proptosis, eyelid retraction, and exposure of the globe. The remaining patients experience enlargement of one or more of the extraocular muscles, leading to conjunctival and eyelid edema and congestion, restricted ocular movement with resultant diplopia, and optic nerve compression leading to compressive optic neuropathy.

Compressive optic neuropathy (CON) in Graves' disease caused by hypertrophy of levator and superior rectus muscles: A case report

RATIONALE

Enlargemento of the medial rectus is the most predominant factor of compressive optic neuropathy (CON) in Graves' disease. This case report indicates that CON could develop only from the hypertrophic superior levator and superior rectus (SL/SR) muscle in a patient with poorly controlled Graves' disease, and described the possible risk of FT3-thyrotoxicosis with a prominent goiter to develop the current rare case with a review of the literature.

PATIENT CONCERNS

A 66-year-old woman undergoing endocrine management of hyperthyroidism with prominent goiter visited the Department of Ophthalmology due to right-eye upper-eyelid retraction.

DIAGNOSES

At initial presentation, the right and left margin reflex distance-1 (MRD-1) was 3.2 mm and 2.1 mm, respectively, and no proptosis or visual dysfunction was observed. Despite insufficient hormonal regulation, she refused to undergo goiter removal. The upper eyelid retraction gradually worsened to 7.7 mm of MRD-1, followed by the onset of 20 prism diopters (PD) of the right hypertropia, resulting in right-eye CON after 6 months. Her free thyroxin level was 3.88 ng/dl and free triiodothyronine was 24.90 pg/ml. Computed tomography and magnetic resonance imaging showed only SL/SR enlargement in the right orbit.

INTERVENTIONS

Intravenous steroid and radiation therapy resulted in visual improvement; however, a prominent upper eyelid retraction and 35PD of hypertropia remained in her right eye. Orbital decompression, upper retraction repair, and superior rectus recession were performed to prevent the recurrence of CON and correct any disfigurement.

OUTCOMES

The combination of conventional intravenous steroid pulse therapy, radiotherapy, and orbital decompression was effective, and no recurrence was observed for more than 1.5-years postoperatively.

LESSONS

Enlargement of the SL/SR muscle complex may independently induce the CON. We believe that strict attention should be paid to patients with triiodothyronine thyrotoxicosis with progressive eyelid retraction and hypertropia.

Dysthyroid optic neuropathy: evaluation and management

BACKGROUND

Dysthyroid optic neuropathy (DON) is a serious complication of Graves orbitopathy (GO) from optic nerve dysfunction that may result in permanent loss of vision.

PURPOSE

This paper reviews the current knowledge of DON, including its pathogenesis and epidemiology, clinical and radiologic features, and management choices and outcomes.

METHODS

Literature review and author retrospective case series.

RESULTS

Over 90% of DON cases are related to nerve compression by enlarged extraocular muscles (EOM) while the remainder are caused by stretching of the optic nerve without compression. DON's incidence is 5-8% of GO cases. Risk factors include advancing age, male gender, smoking and diabetes mellitus, and these cases should be referred promptly to an ophthalmologist or GO clinic to rule out DON and for ongoing care. Clinical features of DON may include reduction in central and colour vision (unexplained by other ocular disorders), afferent pupil defect and/or optic disc edema. Since most cases are associated with enlarged EOM, restricted motility and soft tissue venous congestion are common. Visual fields and optical coherence tomography (OCT) help confirm the diagnosis while CT or MRI Scans show apical optic nerve compression or proptosis with optic nerve stretch. Standard therapy includes iv/oral corticosteroids (CS) with partial response in most cases, but often relapse with tapering. Radiotherapy may delay or avoid surgery and may prevent the onset of DON when combined with CS in high-risk individuals. The benefits of newer biologic targeted therapy are not clear. Orbital decompression surgery often has positive outcomes, even in cases of severe vision loss or delayed surgery. The most common surgical complication is worsening strabismus, which may worsen visual function and quality of life. In rare cases, permanent vision loss from DON may occur despite full therapy.

CONCLUSIONS

Although DON may cause vision loss, most cases are reversible if recognized and managed in a timely manner.

A Nomenclature to Describe the Sequence of Visual Field Defects in Progressive Thyroid Eye Disease-Compressive Optic Neuropathy (An American Ophthalmological Society Thesis)

PURPOSE

To create a novel nomenclature to characterize the longitudinal sequence of visual field (VF) defects in patients with progression of thyroid eye disease-compressive optic neuropathy (TED-CON).

METHODS

A retrospective review of records from 1 institution identified patients with progressive Humphrey VF defects secondary to TED-CON. The VF defects were analyzed by 2 independent reviewers and classified into 1 of 10 categories, divided into 3 stages that reflect the observed progression pattern, plus a miscellaneous category (stage X). Stage 1 VF defects are the earliest detectable and involve the inferior visual field with 3 levels of severity. Stage 2 VF defects include 2 distinguishable levels of severity and occur as the inferior defects advance above the horizontal midline to involve the superior VF. Stage 3 involves progression of stage 2 VF defects to complete loss of inferior and superior hemifields.

RESULTS

Of 234 VFs in 37 eyes of 23 subjects, inferior defects were most common, including stage 1a (small inferior paracentral defect) in 22 of 234 VFs (9.4%), stage 1b (large inferior paracentral defect) in 112 of 234 VFs (47.9%), and stage 1c (inferior altitudinal defect) in 11 of 234 VFs (4.7%). Stage 2a (inferior altitudinal with superior advancement above the horizontal meridian) occurred in 41 of 234 VFs (17.5%), stage 2b (inferior altitudinal with superior arcuate) occurred in 6 of 234 VFs (2.6%), and stage 3 (total loss) occurred in 5 of 234 VFs (2.1%). The longitudinal sequence of VF defects from the 37 eyes of 23 patients was analyzed. Thirty-one of 37 eyes (83.8%) demonstrated a predictable progression pattern from least to more severe: stage 1a, stage 1b, stage 1c, stage 2a, stage 2b, and stage 3. A reverse order of VF defect progression was noted in 15 eyes with improving TED-CON. A minority of progression patterns (16.2%) originated from stage X (central/paracentral, enlarged blind spot, and scatter).

CONCLUSIONS

Humphrey VF defects resulting from TED-CON are most often inferior, often have a predictable pattern of progression, and can be categorized into a novel descriptive nomenclature system. NOTE: Publication of this article is sponsored by the American Ophthalmological Society.

Visual field and orbital computed tomography correlation in dysthyroid optic neuropathy due to thyroid eye disease

Purpose: The pathogenesis of dysthyroid optic neuropathy (DON) in thyroid eye disease (TED) is thought to be compression of the apical optic nerve by hypertrophied extraocular muscles. We correlated worsening DON to the area occupied by extraocular muscles.Methods: Records of adults with TED DON evaluated from 1/1/2013 to 1/1/2018 were retrospectively reviewed. Each patient's visual field with the worst mean deviation (MD) was selected. Orbit CT scans were reviewed. Reformatted oblique coronal images were created perpendicular to the optic nerve. The cross-sectional area (CSA) of the orbit and each muscle group was measured and expressed as ratios of the CSA of the orbital apex. Univariate and multivariate analysis was performed for predictors of HVF MD.Results: 34 orbits with TED DON were analyzed. On orbital CT, the superior muscle complex occupied 15% of the apex (range 6-26%), inferior 18% (range 6-33%), lateral 10% (range 4-18%), medial 17% (range 8-27%), and all combined 61% (range 28-80%). Increasing total muscle area and superior complex area correlated with worsening MD. In multivariate linear regression, the superior muscle complex remained a significant predictor of MD (p = 0.01) over total muscle area (p = 0.25).Conclusions: Enlargement of extraocular muscles is common in TED, but DON occurs in only 6%. Our findings demonstrate that as DON worsens, as quantified by visual field MD, the superior muscle complex crowds the apex. This is consistent with the typical inferior visual field findings seen in TED DON. Hypertrophy of the superior rectus and levator palpabrae superioris complex may be predictive of worsening DON.

Relationships between eyelid position and levator-superior rectus complex and inferior rectus muscle in patients with Graves' orbitopathy with unilateral upper eyelid retraction

PURPOSE

To assess the relationships between eyelid position and levator palpebrae superioris (LPS)-superior rectus (SR) complex and inferior rectus (IR) muscle volume in patients with Graves' orbitopathy (GO) with unilateral upper eyelid retraction.

METHODS

This was a cross-sectional observational study of 48 patients with GO with unilateral upper eyelid retraction. To measure muscle volume, computerized tomography scans were performed, and 3D images were analyzed. Digital photographs were taken, and vertical eyelid height was measured using computed eyelid analysis software. The measured muscle volumes and eyelid heights were assessed, and correlation analysis was performed. To verify the parameters that are predictive for the presence of upper eyelid retraction, receiver operating characteristic curves were analyzed, and logistic regression was performed.

RESULTS

The volume of the LPS/SR muscle complex in the eyes with upper eyelid retraction was increased in 41 eyes (85.4%). The mean volume of the LPS/SR complex was 0.92 ± 0.40 cm³ in the eyes with upper eyelid retraction and 0.72 ± 0.27 cm³ in the contralateral eyes (p < 0.0001). While there was no correlation between LPS/SR complex volume and margin reflex distance1 (MRD1, the vertical distance between the center of the pupil to the center of the upper eyelid margin) (R = 0.024, p = 0.869), MRD1 and MRD2 (the vertical distance between the center of the pupil and the center of the lower eyelid margin) in the retracted eyes were negatively correlated (R = - 0.441, p = 0.002). In patients with upper eyelid retraction without increased LPS/SR complex volume, IR volume and MRD2 of the contralateral eye were 0.48 ± 0.10 cm³ and 5.92 ± 0.45 mm, respectively. In the retracted eye, they were 0.37 ± 0.17 cm³ and 5.32 ± 0.59 mm, respectively (p = 0.018, and 0.028). Regression models incorporating LPS/SR complex volume, MRD1, and lid lag could predict the presence of upper eyelid retraction with an accuracy of 92.5%.

CONCLUSIONS

In patients with GO, increased LPS/SR complex volume in the retracted eye and increased IR volume of the contralateral eye were both associated with unilateral upper eyelid retraction. The combination of LPS/SR complex volume, MRD1, and lid lag can be used as a reliable index of upper eyelid retraction in patients with GO.

Review of extraocular muscle biopsies and utility of biopsy in extraocular muscle enlargement

Aims

To review the distribution of pathology in extraocular muscle (EOM) biopsies performed at a tertiary orbital centre, identify clinical and imaging features which are associated with benign or malignant diseases and indicate when biopsy is necessary for EOM enlargement.

Methods

Retrospective case series including 93 patients with EOM enlargement who underwent an EOM biopsy. Clinical, radiological and histopathological information was recorded from the medical records. Statistical analysis was used to compare variables between patients with malignant and benign biopsies.

Results

The median age of subjects was 61.1 years. Forty-eight cases (52%) were benign and 45 (48%) were malignant. Those with malignant pathology were significantly older (P<0.0001). Males were more likely affected by a benign disease and females by a malignancy (P=0.029). A history of malignancy (P<0.0001) and diplopia (P=0.029) were significant factors in predicting a malignancy. Pain (P=0.005) and eyelid erythema (P=0.001) were more likely in benign conditions. Idiopathic orbital inflammation was the most common benign diagnosis and lymphoma the most common malignancy.

Conclusions

Biopsy is warranted in those with an atypical presentation of EOM enlargement or suspected of having a malignancy. Some features such as age, gender, pain, diplopia, history of malignancy and eyelid erythema may help indicate a particular diagnosis; however, clinical features and imaging findings are often not pathognomonic of each disease.