Effect of Orbital Decompression on Corneal Topography in Patients with Thyroid Ophthalmopathy

Corneal Morphological and Biomechanical Changes in Thyroid-Associated Ophthalmopathy

PURPOSE

This study aimed to evaluate corneal morphological and biomechanical changes in patients with thyroid-associated ophthalmopathy (TAO) and their correlations with activity and severity.

METHODS

Patients diagnosed with TAO were recruited and divided into groups by activity and severity. All subjects underwent a complete ophthalmic examination, including magnetic resonance imaging. Corneal topography was measured using a Pentacam device, and biomechanical parameters were obtained using a CorVis ST tonometer. Correlations among the corneal parameters, clinical activity score, and NOSPECS score were analyzed. Areas under the receiver operating characteristic curves were calculated to evaluate the diagnostic accuracy of corneal changes for active and severe TAO.

RESULTS

Fifty-three eyes with TAO and 16 healthy eyes were enrolled in our study. The back elevation, CorVis biomechanical index, tomographic and biomechanical index, stiffness parameter at the first applanation, deviation from normality in back elevation, relational thickness, and overall deviation from normality were significantly increased in patients with TAO (all P <0.05), whereas the smallest corneal thickness, maximum Ambrósio relational thickness, and deformation amplitude (DA) ratio were significantly decreased (all P <0.05). The clinical activity score was strongly positively correlated with back elevation (γ = 0.515, P <0.001). The NOSPECS score was strongly positively correlated with relational thickness and tomographic and biomechanical index (γ = 0.429 and 0.515, P <0.001) and negatively correlated with maximum Ambrósio relational thickness (γ = -0.53, P <0.001). Moreover, maximum Ambrósio relational thickness and the Ambrósio relational thickness through the horizontal meridian showed desirable diagnostic capacity in distinguishing mild TAO from moderate-severe TAO (areas under the receiver operating characteristic curve, 0.799 and 0.769).

CONCLUSIONS

Corneal morphological and biomechanical changes were found in patients with TAO, which might be related to the presence of inflammation. Measurements of corneal morphological and biomechanical parameters could serve as references in evaluating TAO.

Corneal topographic changes in patients with thyroid eye disease: A retrospective cross-sectional study

PURPOSE

This study aimed to evaluate corneal topographic findings in patients with thyroid eye disease (TED) using a Galilei camera and compare their corneal topographic parameters with those of control patients.

METHODS

This retrospective cross-sectional study included 52 eyes of 26 patients with TED (study group) and 40 eyes of 20 controls treated at a tertiary medical center in Taiwan between January and December 2021. All participants underwent basic ophthalmological examinations, corneal topography examination using a Galilei dual Scheimpflug camera, thyroid function examination, and orbital computed tomography. The corneal topographic parameters and cross-sectional area of the extraocular muscles were compared between the TED and control groups.

RESULTS

Several corneal topographic parameters, including the Inferior-Superior Index, Keratoconus Prediction Index, Surface Asymmetry Index, Surface Regularity Index, simulated keratometry astigmatism, and anterior instantaneous astigmatism axis, differed significantly between the groups (P ≤ 0.05). The anterior instantaneous astigmatism axis was more oblique in the TED group than in the control group. A scatter plot revealed a more scattered distribution in the anterior instantaneous astigmatism axis in the TED group than in the control group. However, the corneal topographic parameters did not differ significantly among the different thyroid dysfunction groups.

CONCLUSIONS

The corneas of patients with TED are suspicious and keratoconus-like, and TED can increase anterior corneal astigmatism in the oblique axis, albeit with large variations in the extent of change. These TED-related corneal changes may aid in the early diagnosis of TED, especially "silent" TED.

Secondary Effects of Orbital Decompression in Thyroid Eye Disease: A Review

PURPOSE

Orbital decompression is mainly performed in thyroid eye disease to reduce proptosis and retrobulbar pressure, to improve venous congestion, and to relieve optic nerve compression. Secondary effects of orbital decompression are also occasionally encountered. The aim of this study was to review the secondary effects of orbital decompression.

METHODS

This is a comprehensive literature review that summarizes the secondary effects of orbital decompression.

RESULTS

Decreased intraocular pressure, inter-pupillary distance, and eyelid pressure, and improvement of eyelid retraction, lateral flare, orbital discomfort, and psychosocial condition after orbital decompression are favorable changes for patients. In contrast, refractive changes in some patients and decreased Bell's phenomenon and nasal function worsen patients' condition.

CONCLUSION

These favorable changes may reduce the patients' burden for treatment of thyroid eye disease. In contrast, as some of the adverse effects significantly worsen the patients' disease condition, we should carefully monitor these changes.

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.

An update on endoscopic orbital decompression

PURPOSE OF REVIEW

Endoscopic orbital decompression is an ever-evolving surgical procedure with modifications as well as new indications for the procedure. The purpose of this review is to update the reader on optimizing patient selection, surgical timing, highlight the latest modifications to surgical technique and to evaluate surgical outcomes that can be achieved.

RECENT FINDINGS

Patient selection, disease pathology, and optimization of technology can lead to improved outcomes. Changes in technology continue to modify surgical techniques and surgical training, working towards decreased surgical complications with improved outcomes. Historically multiple approaches have been used for orbital decompression and this highlights that a balanced orbital decompression usually leads to the best outcome.

SUMMARY

Orbital decompression has evolved significantly since its inception over 100 years ago. Identifying the right patient, the ideal timing, and the indication for the procedure with utilization of technology can lead to improved outcomes and decreased complications.

Orbital decompression for thyroid eye disease: methods, outcomes, and complications

PurposeTo determine the safety and effectiveness of orbital decompression for thyroid eye disease (TED) in our unit. To put this in the context of previously published literature.Patients and methodsA retrospective case review of all patients undergoing orbital decompression for TED under the care of one orbital surgeon (SMS) between January 2009 and December 2015. A systematic literature review of orbital decompression for TED.ResultsWithin the reviewed period, 93 orbits of 55 patients underwent decompression surgery for TED. There were 61 lateral (single) wall decompressions, 17 medial one-and-a-half wall, 11 two-and-a-half wall, 2 balanced two wall, and 2 orbital fat only decompressions. For the lateral (single) wall decompressions, mean reduction in exophthalmometry (95% confidence interval (CI) was 4.2 mm (3.7-4.8), for the medial one-and-a-half walls it was 2.9 mm (2.1-3.7), and for the two-and-a-half walls it was 7.6 mm (5.8-9.4). The most common complications were temporary postoperative numbness (29% of lateral decompressions, 17% of other bony decompressions, OR 0.50, 95% CI 0.12-2.11) and new postoperative diplopia (9% of lateral decompressions, 39% of other bony decompressions, OR 6.8, 95% CI 1. 5-30.9). Systematic literature searching showed reduction in exophthalmometry for lateral wall surgery of 3.6-4.8 mm, with new diplopia 0-38% and postoperative numbness 12-50%. For other bony decompressions, reduction in exophthalmometry was 2.5-8.0 mm with new diplopia 0-45% and postoperative numbness up to 52%.ConclusionDiffering approaches to orbital decompression exist. If the correct type of surgery is chosen, then safe, adequate surgical outcomes can be achieved.