Update on Graves Disease

Advances in Treatment of Mild, Moderate and Severe Thyroid Eye Disease

Diego Strianese

Disclosures

Curr Opin Ophthalmol. 2017;28(5):505-513. 

In This Article

Advances in Assessment and Management of Inactive Disease

Many different techniques and approaches have been described for orbital decompression surgery, including one, two and three-wall decompression with or without orbital fat removal with or without the use of the endoscope.[45] A recent survey of the America Society of Ophthalmic Plastic and Reconstructive Surgery found that despite the technological advances made in the field of modern endoscopic surgery, no single approach has been adopted as the gold standard.[46] There is a general agreement that the specific surgical approach should be tailored to each patient depending on the degree of exophthalmos and the preoperative computed tomography (CT) or MRI findings.

The exophthalmos reading can be variable depending on the method used and observer experience. In a prospective, international, multicenter, observational study, three types of axial globe position evaluation were examined together with the radiologic, clinical and photographic findings. The upright clinical exophthalmometry resulted in the most accurate method to estimate proptosis in TED.[47]

CT scans show that most patients have enlargement of both the orbital fat compartments and the extraocular muscles and that others appear to have involvement of only the adipose tissue or extraocular muscle. Lipogenic subtype orbitopathy or myogenic subtype orbitopathy is differentiated depending on which component is predominant.[48] Calculation of orbital soft tissue volumes may be crucial in assessing surgical approach. An MRI-based computer-assisted segmentation method has been developed to automatically calculate the volumes of fat and muscles for each orbital quadrant of each eye. This regional automated assessment of intraorbital fat could be useful for more accurate surgical planning and follow-up studies.[49] Recently, the presence of bony remodeling has been demonstrated in TED, likely related to the expansion of the intraorbital soft tissue volume. CT scans of 124 patients with TED and 138 controls were retrospectively reviewed, with the aim of measuring three parameters: the angle of the inferomedial orbital strut, the angle of the medial wall and the diameters of the extraocular muscles overall. The two bony parameters were found to be significantly modified (P < 0.001) in patients with TED compared to controls. There was also a negative correlation between the angle of the medial wall and the calculated average cross-sectional area of the medial rectus in TED group (r = –0.23, P = 0.01)[50]

Diplopia correction in TED may be difficult because of the unpredictability of the results and the high risk of postoperative drift toward overcorrection. Vertical squint surgery poses a significant surgical challenge. In a study of 42 patients treated with adjustable suture for vertical diplopia, the authors found that 71.4% were free of diplopia postoperatively; however, five patients experienced overcorrection at 3 weeks, seven at 3 months and eight at 1 year. As adjustable surgery for vertical strabismus in TED may result in late overcorrection and the need for further intervention, the authors proposed that aiming for an immediate postadjustment angle of eight prism dioptres of undercorrection for near would allow for postoperative drift and reduce the chance of a late overcorrection[51]

Our Recommendations in Light of the Recent Therapeutic Advancements

The definition of mild, moderate and severe TED is based on the combination of objective findings (VISA or CAS) and the subjective impact of the disease for that individual[4]

Comments

3090D553-9492-4563-8681-AD288FA52ACE

processing....