Observing pretibial myxedema in patients with Graves' disease using digital infrared thermal imaging and high-resolution ultrasonography: for better records, early detection, and further investigation

Abstract

Objective: Pretibial myxedema (PM) is a manifestation of Graves' disease (GD). Currently, its diagnosis depends on physicians' observation and biopsy. No satisfactory, objective, and non-invasive tool is available to record and investigate lesions. Digital infrared thermal imaging (DITI) detects surface temperature, and sonography reflects composition changes in soft tissue. This study was aimed to observe changes in DITI and sonography in PM, and to evaluate their clinical usefulness. Methods: Nineteen GD patients with PM, 22 GD patients with mild diffuse non-pitting edema over lower legs, 46 GD patients with normal appearance of lower legs, and 14 normal volunteers were recruited for observation with DITI; 8, 21, 21, and 11 of them respectively also received soft tissue sonography for investigating the pathogenesis of DITI change. Results: Lower leg temperatures of normal volunteers decreased gradually from proximal to distal parts. In all 19 patients with PM, DITI showed abnormally low focal temperatures over the lesions. In GD patients with mild diffuse non-pitting edema and GD patients with normal appearance of lower legs, DITI showed abnormally low focal temperature in 90.9 and 65.2% of the patients respectively. Areas of clinically visible PM and low focal temperature detected by DITI were sonographically characterized with increased skin thickness, hypoechoic substance deposition in the cutaneous tissue, and blurred boundary lines between dermis and subcutaneous tissue. TSH receptor antibody level correlated positively and significantly with skin thickness change and adjusted temperature difference between the center of temperature defect and the surrounding skin (PZ0.046 and 0.033 respectively). Conclusions: By using DITI and sonography, we detected characteristic changes in PM. These techniques are helpful in recording and may be useful tools to detect early changes of PM.

Early assessment of the efficacy of digital infrared thermal imaging in pediatric extremity trauma

“…It has probably been most investigated for breast cancer [6][7][8][9][10][11][12][13], but growing literature reports its use in a variety of other medical conditions [14][15][16][17][18][19][20][21][22][23][24][25][26][27][28][29]. To the best of our knowledge, however, there are only two reports of the use of DITI in skeletal trauma.…”

Preliminary experience of the use of high‐resolution skin ultrasound for the evaluation of extrathyroidal manifestations of Graves’ disease and response to UVA‐1 phototherapy

“…2 Non-invasive skin imaging techniques are not routinely used for monitoring response to therapy of these lesions: US of the Graves's eyelids of was never reported, while PTM lesions were rarely examined with medium resolution US in order to assess dermal thickness. 4,5 In our preliminary observations, HRUS showed GAGs deposits as moderately hyperechoic aggregates with "cotton-like" aspect in the reticular dermis and in the underlining subcutaneous adipose tissue in both PTM and GO lesions. Moreover, we identified GAGs deposits also in both the reticular dermis and fibro-adipose suborbicularis tissue of the eyelid, which is an area subjected to chronic microtraumatism as well.…”

“…In particular, keratopath and photophobia, due to exophthalmos and eyelid retraction, impaired eye mobility and diplopia due to the compression of optic nerve and extra-ocular muscles are usually minimally modified, as well as leg plaques/nodules and lymphedema. [1][2][3][4] We here report for the first time on two cases presenting with moderate to severe GO and PTM treated with UVA-1 phototherapy and monitored with skin high-resolution ultrasound (HRUS).…”

Morphological Diversity of Pretibial Myxedema and Its Mechanism of Evolving Process and Outcome: A Retrospective Study of 216 Cases

“…Recently, Shih et al [38] found that TRAb level correlated positively and significantly with skin thickness change. In our case series, serum TRAb levels were found to be positively correlated with severity of PTM lesions (variants).…”