Effect of Levothyroxine on Left Ventricular Ejection Fraction in Patients With Subclinical Hypothyroidism and Acute Myocardial Infarction: A Randomized Clinical Trial.
Jabbar Avais,Ingoe Lorna,Junejo Shahid,Carey Peter,Addison Caroline,Thomas Honey,Parikh Jehill D,Austin David,Hollingsworth Kieren G,Stocken Deborah D,Pearce Simon H S,Greenwood John P,Zaman Azfar,Razvi Salman
Importance:Thyroid hormones play a key role in modulating myocardial contractility. Subclinical hypothyroidism in patients with acute myocardial infarction is associated with poor prognosis. Objective:To evaluate the effect of levothyroxine treatment on left ventricular function in patients with acute myocardial infarction and subclinical hypothyroidism. Design, Setting, and Participants:A double-blind, randomized clinical trial conducted in 6 hospitals in the United Kingdom. Patients with acute myocardial infarction including ST-segment elevation and non-ST-segment elevation were recruited between February 2015 and December 2016, with the last participant being followed up in December 2017. Interventions:Levothyroxine treatment (n = 46) commencing at 25 µg titrated to aim for serum thyrotropin levels between 0.4 and 2.5 mU/L or identical placebo (n = 49), both provided in capsule form, once daily for 52 weeks. Main Outcomes and Measures:The primary outcome measure was left ventricular ejection fraction at 52 weeks, assessed by magnetic resonance imaging, adjusted for age, sex, type of acute myocardial infarction, affected coronary artery territory, and baseline left ventricular ejection fraction. Secondary measures were left ventricular volumes, infarct size (assessed in a subgroup [n = 60]), adverse events, and patient-reported outcome measures of health status, health-related quality of life, and depression. Results:Among the 95 participants randomized, the mean (SD) age was 63.5 (9.5) years, 72 (76.6%) were men, and 65 (69.1%) had ST-segment elevation myocardial infarction. The median serum thyrotropin level was 5.7 mU/L (interquartile range, 4.8-7.3 mU/L) and the mean (SD) free thyroxine level was 1.14 (0.16) ng/dL. The primary outcome measurements at 52 weeks were available in 85 patients (89.5%). The mean left ventricular ejection fraction at baseline and at 52 weeks was 51.3% and 53.8%, respectively, in the levothyroxine group compared with 54.0% and 56.1%, respectively, in the placebo group (adjusted difference in groups, 0.76% [95% CI, -0.93% to 2.46%]; P = .37). None of the 6 secondary outcomes showed a significant difference between the levothyroxine and placebo treatment groups. There were 15 (33.3%) and 18 (36.7%) cardiovascular adverse events in the levothyroxine and placebo groups, respectively. Conclusions and Relevance:In this preliminary study involving patients with subclinical hypothyroidism and acute myocardial infarction, treatment with levothyroxine, compared with placebo, did not significantly improve left ventricular ejection fraction after 52 weeks. These findings do not support treatment of subclinical hypothyroidism in patients with acute myocardial infarction. Trial Registration:isrctn.org Identifier: http://www.isrctn.com/ISRCTN52505169.
Cardiac oxidative metabolism, function, and metabolic performance in mild hyperthyroidism: a noninvasive study using positron emission tomography and magnetic resonance imaging.
Bengel Frank M,Lehnert Juliane,Ibrahim Tareq,Klein Christoph,Bülow Hubertus P,Nekolla Stephan G,Schwaiger Markus
Thyroid : official journal of the American Thyroid Association
Using noninvasive imaging, we have previously demonstrated that myocardial efficiency is impaired in hypothyroidism and improves after establishing euthyroid conditions. Little is known about the effects of abnormally elevated thyroid hormone exposure on cardiac metabolic performance. We studied 10 patients without evidence of heart disease in mild hyperthyroidism, and after therapy under euthyroid conditions. Cardiac oxidative metabolism was quantified by positron emission tomography with [(11)C]acetate. Left ventricular geometry was determined by cine magnetic resonance imaging. Myocardial efficiency, defined by the relation between work and oxygen consumption, was estimated using the work metabolic index [WMI = stroke volume * systolic blood pressure * heart rate/(oxidative metabolism * ventricular mass)]. In hyperthyroidism, heart rate and cardiac output were expectedly higher. Peripheral vascular resistance was reduced. Differences of blood pressure, stroke volume, and ventricular mass were not observed. Oxidative metabolism was significantly higher, but WMI was not different from the euthyroid state. In summary, while improvement of efficiency through thyroid hormone substitution was observed previously in hypothyroidism, our data in mild hyperthyroidism suggest an increase of oxygen consumption, paralleled by an increase of work. Thus, moderately elevated thyroid hormone levels neither result in further increase nor in reduction of cardiac metabolic performance.
Left ventricular myocardial T1 mapping and strain analysis evaluate cardiac abnormality in hypothyroidism.
Liu Min,Liu Weifang,Zhang Peiyao,An Jing,Wang Guang
The international journal of cardiovascular imaging
Cardiovascular Magnetic Resonance (CMR)-based T1 mapping and Heart Deformation Analysis (CMR-HDA) can assess the myocardial tissue characteristic and strain of cardiomyopathy. Whether they can assess cardiac abnormality of hypothyroidism (HT) is unknown. We aim to analysis left ventricular (LV) T1 values and strain of patients with overt HT (OHT) and subclinical HT (SHT) with CMR-based T1 mapping and HDA. This study prospectively included 32 OHT patients, 23 SHT patients and 27 healthy controls who underwent CMR. LV T1 mapping was obtained with a Modified Look-Locker Inversion Recovery sequence while LV circumferential strain (LVCS) and radial strain (LVRS), LV longitudinal strain (LVLS) were respectively analyzed on the short-axial and four-chamber cines with HDA. LV Eject Fraction among three groups were similar (p = 0.676). LV myocardial T1 correlated with LVCS (r = 0.734, p < 0.001) and LVRS (r = - 0.340, p = 0.011). LV myocardial T1 of OHT patients significantly increased in comparison with SHT patients (t = 5.403, p < 0.001) and normal controls (t = 10.197, p < 0.001), meanwhile, LV myocardial T1 of SHT patients were higher than that of controls (t = 2.629, p = 0.013). Compared with SHT patients (t = 1.925, p = 0.031) and normal controls (t = 2.875, p = 0.006), LVCS of OHT patients reduced while LVCS of SHT patients were lower than that of normal controls (t = 2.451, p = 0.020). LVRS of SHT patients were higher than OHT patients (t = 2.778, p = 0.008), but comparable to normal controls (t = 1.134, p = 0.266). LVLS of SHT and OHT significantly impaired in comparison with normal control. The increased LV myocardial T1 value and reduced strain were found in HT. CMR-based LV myocardial T1 and stain analysis are useful to evaluate myocardial tissue characteristic and mechanics in both overt and subclinical hypothyroidism.
Effects of short-term levothyroxine therapy on myocardial injuries in patients with severe overt hypothyroidism: Evidence from a cardiac MRI Study.
Gao Xia,Chen Zhe,Liu Min,Jia Yu-Mei,Yang Ning,Yao Zhi,Feng Xiao-Meng,Xu Yuan,Wang Guang
Journal of magnetic resonance imaging : JMRI
PURPOSE:To investigate using magnetic resonance imaging (MRI) myocardial injuries and cardiac function in patients with newly diagnosed severe primary overt hypothyroidism (HT) before and after achieving euthyroidism by short-term levothyroxine treatment. Levothyroxine treatment improves cardiovascular performance and ventricular remodeling in patients with HT, but diffuse myocardial injuries induced by HT are difficult to detect clinically. MATERIALS AND METHODS:Myocardial longitudinal relaxation time (T ) mapping using the modified Look-Locker inversion-recovery (MOLLI) sequences at 3.0T was performed before and after euthyroidism was achieved by levothyroxine treatment in 24 patients with Hashimoto's thyroiditis, and compared to 17 healthy controls. Subjects underwent measurements of T values and left ventricular stroke volume (SV), ejection fraction (EF), cardiac index (CI), and peak filling rate (PFR). Cardiac data were expressed as an index, as per body surface area, except for heart rate and EF. RESULTS:Patients with untreated HT exhibited significantly longer native myocardial T values (all P < 0.05) accompanied by reduced SV (30.7 ± 5.6 vs. 34.9 ± 6.8 mL/m , P < 0.05), CI (2.1 ± 0.4 vs. 2.4 ± 0.4 L/min/m , P < 0.05), and PFR (3.5 ± 0.9 vs. 4.2 ± 1.1 EDV/s, P < 0.05) compared to healthy controls at baseline. Achieving euthyroidism resulted in a significant decrease in T values and improved SV, CI, and PFR values (all P < 0.05) in the patients with HT. Negative correlations of the T values with free triiodothyronine (r = -0.55, P < 0.001) and PFR (r = -0.46, P = 0.0016) were observed. CONCLUSION:We suggest that the negative effect induced by severe overt HT on the cardiovascular system can be significantly improved by restoring euthyroidism with short-term levothyroxine therapy. LEVEL OF EVIDENCE:1 Technical Efficacy: Stage 2 J. MAGN. RESON. IMAGING 2017;46:897-904.
Native Magnetic Resonance T1-Mapping Identifies Diffuse Myocardial Injury in Hypothyroidism.
Gao Xia,Liu Min,Qu Aijuan,Chen Zhe,Jia Yumei,Yang Ning,Feng Xiaomeng,Liu Jia,Xu Yuan,Yang Xinchun,Wang Guang
BACKGROUND AND AIM:Hypothyroidism (HT) is characterized by thyroid hormone deficiencies, which can lead to diffuse myocardial interstitium lesions in patients with HT. Myocardial longitudinal relaxation time (T1) mapping is a potential diagnostic tool for quantifying diffuse myocardial injury. This study aimed to assess the usefulness of T1 mapping in identifying myocardial involvement in HT, and determine the relationship between T1 values and myocardial function. METHODS:A cross-sectional study was conducted with 30 untreated HT patients alongside 23 age- and sex-matched healthy controls. All subjects underwent cardiac magnetic resonance (CMR) with non-contrast (native) T1 mapping using a modified Look-Locker inversion-recovery (MOLLI) sequence to assess the native T1 values of myocardium and cardiac function. RESULTS:Native myocardial T1 values were significantly increased in HT patients, especially those with pericardial effusion (p < 0.05), compared with healthy controls. In addition, significantly reduced peak filling rate (PFR) and prolonged peak filling time (PFT) were obtained (p < 0.05) in HT patients compared with controls. Furthermore, stroke volume (SV) and cardiac index (CI) were significantly lower in HT patients than controls (all p < 0.05). Interestingly, native T1 values were negatively correlated with free triiodothyronine (FT3), PFR, SV and CI (all p < 0.05). CONCLUSION:Diffuse myocardial injuries are common in HT patients, and increased T1 values are correlated with FT3 and cardiac function impairment. These findings indicate that T1 mapping might be useful in evaluating myocardial injuries in HT patients.
Free Triiodothyronine Level Correlates with Myocardial Injury and Prognosis in Idiopathic Dilated Cardiomyopathy: Evidence from Cardiac MRI and SPECT/PET Imaging.
Wang Wenyao,Guan Haixia,Fang Wei,Zhang Kuo,Gerdes A Martin,Iervasi Giorgio,Tang Yi-Da
Thyroid dysfunction is associated with poor prognosis in heart failure, but theories of mechanisms are mainly based on animal experiments, not on human level. We aimed to explore the relation between thyroid function and myocardial injuries in idiopathic dilated cardiomyopathy (IDCM) using cardiac magnetic resonance imaging (MRI), single-photon emission computed tomography (SPECT) and positron emission tomography (PET). Myocardial fibrosis was detected by late gadolinium enhancement (LGE) MRI, and myocardial perfusion/metabolism was evaluated by Tc-MIBI SPECT /F-FDG PET imaging. Across the quartiles of FT3, decreased percentage of segments with LGE and perfusion/metabolism abnormalities were found. As for FT4 and TSH levels, no significant distribution trend of myocardial injuries could be detected. In logistic analysis, FT3 was independently associated with the presence of LGE (OR: 0.140, 95% CI: 0.035-0.567), perfusion abnormalities (OR: 0.172, 95% CI: 0.040-0.738) and metabolism abnormalities (OR: 0.281, 95% CI: 0.081-0.971). After a median follow-up of 46 months, LGE-positive and FT3 < 2.77 pg/mL was identified as the strongest predictor of cardiac events (HR: 8.623, 95% CI: 3.626-16.438). Low FT3 level is associated with myocardial fibrosis and perfusion/metabolism abnormalities in patients with IDCM. The combination of FT3 level and LGE provides useful information for assessing the prognosis of IDCM.
Monitoring glutamate levels in the posterior cingulate cortex of thyroid dysfunction patients with TE-averaged PRESS at 3T.
Zhang Qiujuan,Bai Zhilan,Gong Yan,Liu Xinxin,Dai Xiaoqing,Wang Shejiao,Liu Feng
Magnetic resonance imaging
BACKGROUNDS AND OBJECTIVES:Patients with thyroid dysfunction frequently have neuropsychiatric complaints such as lack of concentration, poor memory, depression, anxiety and mania, which suggest brain dysfunction. However, the underlying process of this dysfunction remains unclear. Recent studies of the glutamatergic system have offered important insight into the neuropsychiatric process. Thus, this study investigates changes in glutamate concentration in patients with thyroid dysfunction. It also clarifies whether Glu levels are related to thyroid hormones via proton magnetic resonance spectroscopy. METHODS:36 untreated patients with thyroid dysfunction (18 hyperthyroidism patients and 18 hypothyroidism patients) and 18 age- and gender-matched controls were included in this study. The posterior cingulate cortex was examined by MRS with TE-averaged PRESS at 3T. The intensity of glutamate, choline, N-acetylaspartate, and creatine was assessed using jMRUI v4.0 software. RESULTS:We found a significant difference among hyper-/hypo- and control groups in Glu (P=0.003) and Cho (P=0.015). The concentrations of glutamate increased (P=0.006) in the posterior cingulate cortex in patients with hypothyroidism and significantly decreased (P=0.002) in hyperthyroidism patients relative to controls. There were no difference in the concentrations of choline between hyperthyroidism patients and controls (P=0.679). Versus the hyperthyroidism group, the hypothyroidism group showed increased glutamate (P=0.018) and choline (P=0.001) in the posterior cingulate cortex. There was no significant difference in the concentrations of NAA or creatine across the three groups (P>0.05). The Glu level correlates with TT3 (P=0.000) and FT3 (P=0.022). CONCLUSION:The signal intensity of glutamate shows significant differences in the region of the posterior cingulate cortex in patients with thyroid dysfunction. This change indicates a potential role of glutamate in the brain dysfunction experience by patients with thyroid hormone disorders.
Ultrasonography compared to magnetic resonance imaging in thyroid-associated Graves' ophthalmopathy.
Vlainich Ana R,Romaldini João H,Pedro Ana B,Farah Chady S,Sinisgalli Cicero A
Arquivos brasileiros de endocrinologia e metabologia
OBJECTIVE:To compare ultrasonography (US) to magnetic resonance imaging (MRI) and the clinical activity score (CAS) in Graves' ophthalmopathy. SUBJECTS AND METHODS:Nineteen patients underwent extraocular muscle thickness measurements by US and MRI, reflectivity by US and signal-intensity ratio by MRI. There were also twelve US control subjects. RESULTS:US median thicknesses were greater than in controls. Correlation was found between US and MRI in the median thickness of the left eye rectus medial muscle as well as between signal-intensity ratio (SIR) and thickness by US. An inverse correlation was found between reflectivity and SIR in the inferior and lateral rectus. On associating the tests for detecting activity the best results were obtained with CAS plus MRI (sensitivity 75%), and US and MRI (positive predictive value 77% and specificity 80%). CONCLUSION:CAS and US results showed poor correlation with MRI results suggesting that they cannot replace each other but when combined these methods can improve the evaluation of thyroid-associated ophthalmopathy.
Recovery from chronic demyelination by thyroid hormone therapy: myelinogenesis induction and assessment by diffusion tensor magnetic resonance imaging.
Harsan Laura-Adela,Steibel Jérôme,Zaremba Anita,Agin Arnaud,Sapin Rémy,Poulet Patrick,Guignard Blandine,Parizel Nathalie,Grucker Daniel,Boehm Nelly,Miller Robert H,Ghandour M Said
The Journal of neuroscience : the official journal of the Society for Neuroscience
The failure of the remyelination processes in multiple sclerosis contributes to the formation of chronic demyelinated plaques that lead to severe neurological deficits. Long-term cuprizone treatment of C57BL/6 mice resulted in pronounced white matter pathology characterized by oligodendrocyte depletion, irreversible demyelination and persistent functional deficits after cuprizone withdrawal. The use of a combination of in vivo diffusion tensor magnetic resonance imaging (DT-MRI) and histological analyses allowed for an accurate longitudinal assessment of demyelination. Injection of triiodothyronine (T(3)) hormone over a 3 week interval after cuprizone withdrawal progressively restored the normal DT-MRI phenotype accompanied by an improvement of clinical signs and remyelination. The effects of T(3) were not restricted to the later stages of remyelination but increased the expression of sonic hedgehog and the numbers of Olig2(+) and PSA-NCAM(+) precursors and proliferative cells. Our findings establish a role for T(3) as an inducer of oligodendrocyte progenitor cells in adult mouse brain following chronic demyelination.
The Emerging Role of Cardiovascular Magnetic Resonance Imaging in the Evaluation of Metabolic Cardiomyopathies.
Mavrogeni S,Markousis-Mavrogenis G,Markussis V,Kolovou G
Hormone and metabolic research = Hormon- und Stoffwechselforschung = Hormones et metabolisme
The aim of this review is to discuss the role of Cardiovascular Magnetic Resonance (CMR) in the diagnosis, risk stratification, and follow-up of metabolic cardiomyopathies. The classification of myocardial diseases, proposed by WHO/ISFC task force, distinguished specific cardiomyopathies, caused by metabolic disorders, into 4 types: 1) endocrine disorders, 2) storage or infiltration disorders (amyloidosis, hemochromatosis and familial storage disorders), 3) nutritional disorders (Kwashiorkor, beri-beri, obesity, and alcohol), and 4) diabetic heart. Thyroid disease, pheochromocytoma, and growth hormone excess or deficiency may contribute to usually reversible dilated cardiomyopathy. Glucogen storage diseases can be presented with myopathy, liver, and heart failure. Lysosomal storage diseases can provoke cardiac hypertrophy, mimicking hypertrophic cardiomyopathy and arrhythmias. Hereditary hemochromatosis, an inherited disorder of iron metabolism, leads to tissue iron overload in different organs, including the heart. Cardiac amyloidosis is the result of amyloid deposition in the heart, formed from breakdown of normal or abnormal proteins that leads to increased heart stiffness, restrictive cardiomyopathy, and heart failure. Finally, nutritional disturbances and metabolic diseases, such as Kwashiorkor, beri-beri, obesity, alcohol consumption, and diabetes mellitus may also lead to severe cardiac dysfunction. CMR, through its capability to reliably assess anatomy, function, inflammation, rest-stress myocardial perfusion, myocardial fibrosis, aortic distensibility, iron and/or fat deposition can serve as an excellent tool for early diagnosis of heart involvement, risk stratification, treatment evaluation, and long term follow-up of patients with metabolic cardiomyopathies.
Magnetic resonance imaging findings of pituitary hyperplasia due to primary hypothyroidism.
Zhang Wei-hong,Zhu Hui-juan,Zhang Xue-wei,Lian Xiao-lan,Dai Wei-xin,Feng Feng,Xing Xiao-ping,Jin Zheng-yu
Zhongguo yi xue ke xue yuan xue bao. Acta Academiae Medicinae Sinicae
OBJECTIVE:To explore the clinical and magnetic resonance imaging (MRI) findings of pituitary hyperplasia due to primary hypothyroidism. METHOD:The clinical presentations, laboratory examinations, and MRI findings of 11 patients with pituitary hyperplasia secondary to primary hypothyroidism diagnosed at our hospitals from the beginning of 2008 to the end of 2011 were retrospectively reviewed. RESULTS:The clinical manifestations in 11 patients included growth arrest(7/8), mental retardation (6/8), cold intolerance and fatigue(6/11), slightly increased body weight (6/11), galactorrhea (3/11), paramenia (8/9), precocious puberty companying vaginal bleeding (2/2),and blurry vision (3/11). Laboratory investigations revealed grossly increased thyroid stimulating hormone, decreased thyroxine, and slightly elevated prolactin levels in all cases. Thyroid antibody was positive in six cases. On MRI, pituitary mass were detected a large intrasellar with/without suprasellar extension in all patients,showing the characteristic of symmetric enlargement. Spherical shape was viewed in 5 cases,with the height of (12.22 ± 3.12)mm. In the other 6 cases, the pituitary mass with the shape of calabash extended superiorly to suprasellar area, with a height of(18.95 ± 2.23)mm. The signal of pituitary mass was isointense to grey matter both on T1 weighted imaging and T2 weighted imaging. Bright short T1 signal in posterior lobe of pituitary was visible. Pituitary stalk was detected only in 4 cases from MRI without dislocation, while the width of pituitary stalk was within the normal limit. CONCLUSIONS:Pituitary hyperplasia should be considered when homogenous enlargement of the pituitary gland is found on MRI. The integration of MRI findings, clinical manifestations, and laboratory findings is helpful for the proper identification of the primary endocrine disease and thus avoid misdiagnosis.
Computed tomography and magnetic resonance imaging in diseases of the thyroid and parathyroid.
Kabala J E
European journal of radiology
Disease of the parathyroid glands presents most often with hypercalcaemia secondary to excess parathormone (PTH) production. This is due to a solitary functioning parathyroid adenoma. The role of imaging is primarily to localise the functioning adenoma. Disease of the thyroid may present with a neck mass or thyroid dysfunction. This paper focuses on the approach and choice of imaging techniques in the evaluation of hypercalcaemia and thyroid masses.
Infraorbital nerve involvement on magnetic resonance imaging in European patients with IgG4-related ophthalmic disease: a specific sign.
Soussan J Ben,Deschamps R,Sadik J C,Savatovsky J,Deschamps L,Puttermann M,Zmuda M,Heran F,Galatoire O,Picard H,Lecler A
OBJECTIVES:To measure the frequency of infraorbital nerve enlargement (IONE) on magnetic resonance imaging (MRI) in European patients suffering from an IgG4-related ophthalmic disease (IgG4-ROD) as compared to patients suffering from non-IgG4-related ophthalmic disease (non-IgG4-ROD). METHODS:From January 2006 through April 2015, 132 patients were admitted for non-lymphoma, non-thyroid-related orbital inflammation. Thirty-eight had both pre-therapeutic orbital MRI and histopathological IgG4 immunostaining. Fifteen patients were classified as cases of IgG4-ROD and 23 patients as cases of non-IgG4-ROD. Two readers performed blinded analyses of MRI images. The main criterion was the presence of an IONE, defined as the infraorbital nerve diameter being greater than the optic nerve diameter in the coronal section. RESULTS:IONE was present in 53% (8/15) of IgG4-ROD cases whereas it was never present (0/23) in cases of non-IgG4-ROD (P < 0.0001). IONE was only present in cases where, on MRI, the inflammation of the inferior quadrant was present and in direct contact with the ION canal. CONCLUSIONS:In European patients suffering from orbital inflammation, the presence of IONE on an MRI is a specific sign of IgG4-ROD. Recognition of this pattern may facilitate the accurate diagnosis for clinicians and allow for the adequate management and appropriate care of their patients. KEY POINTS:• IONE on an MRI is a specific sign of IgG4-ROD. • IONE recognition allows for a quicker diagnosis and appropriate management. • IONE appears when inflammation is in direct contact with the ION canal.
Magnetic resonance imaging of the normal canine thyroid gland.
Taeymans Olivier,Dennis Ruth,Saunders Jimmy H
Veterinary radiology & ultrasound : the official journal of the American College of Veterinary Radiology and the International Veterinary Radiology Association
The magnetic resonance (MR) imaging features of the normal canine thyroid gland were retrospectively compiled from images acquired in 44 dogs presented for a variety of diseases unrelated to the thyroid gland. The appearance of the thyroid gland on different sequences, including pre- and postcontrast T1-weighted, T2-weighted, two-dimensional gradient echo, three-dimensional T2*-weighted gradient echo and proton density weighted images, were described in different image planes. The characteristic shape, location, and intensity of thyroid lobes compared with surrounding structures made them easily detectable in all dogs. The most common location of the thyroid lobes was dorsolateral to the trachea with the maximal cross-sectional area of the lobes located ventral to C2/3 or C3 in more than 85% of the dogs. The majority of the lobes were ovoid on transverse images. An isthmus was seen in one large dog and parathyroid glands could not be seen. The mean maximal thyroid lobe diameter on transverse images was 8.1 mm, being twice the mean diameter of the common carotid artery. Considering the excellent conspicuity and characteristic appearance of the canine thyroid gland, MR imaging can be beneficial in the diagnosis of diffuse thyroid diseases, in differentiating thyroid vs. nonthyroid neck masses and in staging and treatment planning of thyroid tumors in this species.
Thyroid perfusion imaging as a diagnostic tool in Graves' disease--arterial spin labeling magnetic resonance imaging vs. colour-coded Doppler ultrasound.
Müssig K,Schraml C,Rietig R,Martirosian P,Schwenzer N F,Claussen C D,Häring H-U,Schick F,Balletshofer B
RoFo : Fortschritte auf dem Gebiete der Rontgenstrahlen und der Nuklearmedizin
PURPOSE:Though increased thyroid perfusion assessed by colour-coded Doppler ultrasound (CDUS) is characteristic of Graves' disease (GD), sometimes perfusion assessment by CDUS is not possible. In these cases, arterial spin labelling (ASL), a novel magnetic resonance imaging (MRI) technique allowing non-invasive thyroid perfusion quantification, may have additional diagnostic value. We aimed to evaluate the potential of ASL-MRI for assessment of increased blood perfusion in patients with GD compared to CDUS. MATERIALS AND METHODS:Thyroid perfusion was measured by CDUS (volume flow rate calculated from pulsed wave Doppler signals and vessel diameter) and ASL-MRI at 1.5 T in 7 patients with GD and 10 healthy controls. RESULTS:In patients with GD, average perfusion in both thyroid lobes was markedly increased compared to controls. Both techniques applied for volume related perfusion as well as absolute volume flow in thyroid feeding vessels provided similar results (all p=0.0008). Using a cut-off value of 22 ml/min for the volume flow rate assessed by CDUS in the four feeding vessels allowed discrimination between patients with GD and controls in all cases. After adjusting thyroid perfusion for the differences in organ volume, both CDUS and ASL revealed also complete discrimination between health and disease. CONCLUSION:Thyroid perfusion measurement by ASL-MRI reliably discriminate GD from normal thyroid glands. In patients in whom thyroid arteries cannot be depicted by CDUS for technical or anatomical reasons, ASL-MRI may have additional diagnostic value.
Tuberculosis of the thyroid gland: magnetic resonance imaging appearances.
Madhusudhan K S,Seith A,Khadgawat R,Das P,Mathur S
Singapore medical journal
Tuberculosis involving the thyroid gland is a rare occurrence. We report a case of cytologically-diagnosed thyroid gland tuberculosis in a 21-year-old man who presented with thyroid swelling of short duration, and describe the magnetic resonance (MR) imaging appearances of the lesion, which to our knowledge, has not been previously described. We also report a rare complication of abscess formation in the track of the fine needle aspiration. The intermediate signal intensity of the lesions on both T1- and T2-weighted MR images may provide a clue about tuberculosis, as clinical suspicion is low due to the rarity of the disease.
Correlation Between Optical Coherence Tomography and Magnetic Resonance Imaging of Rectus Muscle Thickness Measurements in Graves' Ophthalmopathy.
De-Pablo-Gómez-de-Liaño Lucía,Fernández-Vigo José Ignacio,Merino-Menéndez Salomé,Duque-Muñoz María,Gómez-de-Liaño Rosario
Journal of pediatric ophthalmology and strabismus
PURPOSE:To assess the correlation between optical coherence tomography (OCT) and magnetic resonance imaging (MRI) measurements of extraocular rectus muscle thickness in patients with Graves' ophthalmopathy. METHODS:This was a cross-sectional observational study conducted in 62 eyes of 31 patients with Graves' ophthalmopathy. The disease phase was inactive in 20 patients and active in the remaining 11. The OCT measurements obtained were: medial rectus thickness at 7.2 and 9.2 mm from the limbus and lateral rectus thickness at 8.5 mm from the limbus. MRI measurements were maximum transversal diameter (T-MRI), craniocaudal diameter (CC-MRI), and muscle area (A-MRI). RESULTS:For the whole patient cohort, correlation emerged between the OCT-MR and T-MRI measurements (R = 0.428 to 0.576; P ≤ .002), A-MRI (R = 0.562 to 0.674; P < .001), and CC-MRI (R = 0.286 to 0.293; P ≤ .046). In patients with clinically active Graves' ophthalmopathy, correlations with T-MRI (R = 0.576 to 0.604; P ≤ .010) and A-MRI (R = 0.678 to 0.706; P < .001) were higher. No correlations were detected between OCT and MRI measurements of lateral rectus thickness (P ≥ .177), regardless of disease phase. CONCLUSIONS:The correlations observed suggest OCT could be a complementary assessment or screening method to detect thickening of the anterior portion of the medial rectus muscle in patients with Graves' ophthalmopathy, which may be especially useful when MRI is not available. [J Pediatr Ophthalmol Strabismus. 2019;56(5):319-326.].
Sinonasal papilloma: what influences the decision to request a magnetic resonance imaging scan?
Kasbekar A V,Swords C,Attlmayr B,Kulkarni T,Swift A C
The Journal of laryngology and otology
BACKGROUND:Computed tomography is the standard pre-operative imaging modality for sinonasal papilloma. The complementary use of magnetic resonance imaging as an additional investigation is debated. This study aimed to establish whether magnetic resonance imaging can accurately detect tumour extent and is a useful adjunct to computed tomography. METHODS:A retrospective review was conducted on 19 patients with sinonasal papilloma. The interpretation of computed tomography and magnetic resonance imaging scans, by three clinicians, was conducted by comparing prediction of tumour extent. The perceived necessity of magnetic resonance imaging was compared between clinicians. RESULTS:The addition of magnetic resonance imaging improved accuracy of pre-operative interpretation; specifically, this finding was significant in cases with frontal sinus involvement. Surgeons were more likely than a radiologist to request magnetic resonance imaging, particularly when computed tomography indicated frontal sinus disease. CONCLUSION:Pre-operative combined magnetic resonance imaging and computed tomography helped predict disease in the frontal sinus better than computed tomography alone. A close working relationship between the ENT and radiology departments is important for accurate tumour localisation.
Computed Tomography and MR Imaging of Thyroid Disease.
Traylor Katie Suzanne
Radiologic clinics of North America
Over the past several years, there has been an increase in the discovery of thyroid cancers, likely because of the marked increased utilization of computed tomography (CT) and MR imaging. Despite the increase in number of thyroid cancers, the overall mortality remains unchanged because most of these cancers are the differentiated type and have a more indolent behavior. CT and MR imaging are important in the preoperative evaluation of thyroid goiters and thyroid cancer. This article discusses the imaging characteristics of benign and malignant thyroid diseases, and the important information that needs to be relayed to the surgeon.
[Magnetic Resonance Imaging Features and Their Pathological Mechanisms of Hashimoto's Encephalopathy].
Yang Shuai,Wang Xiao-Yi,Liao Wei-Hua,Xiao Hai-Qing,Zhou Gao-Feng,Hu Ping,Peng Xian-Jing
Zhongguo yi xue ke xue yuan xue bao. Acta Academiae Medicinae Sinicae
Objective To analyze the routine and functional magnetic resonance imaging(MRI) features and their potential pathological mechanisms of Hashimoto's encephalopathy(HE). Methods The clinical data and routine and functional MRI images of 30 HE patients who were treated in our center from January 2010 to April 2017 were retrospectively reviewed. Among them,15 patients were examined with contrast-enhanced MRI,16 with diffusion-weighed imaging(DWI),8 with magnetic resonance angiography,2 with magnetic resonance spectroscopy,and 1 with both arterial spin labeled perfusion imaging and diffusion tensor imaging. Seven patients had consecutive clinical and imaging data. The distribution,MRI signals,and functional MRI features of HE were analyzed. Results Among 30 HE patients,routine MRI showed negative results in 8 cases and abnormal findings in 22 cases. Among 22 abnormal cases,9 were characterized by small cerebral vascular disease and 13 had non-specific abnormalities;of these 13 cases,12 had lesions mainly located at the supratentorial white matter,11 had multiple lesions,and 2 had lesions complicated with cerebellum atrophy. The lesions were focal or confluent,punctate or small patchy,showing abnormal signal intensity with iso-or hypo-intensity on T1-weighed imaging,hyper-intensity on both T2-weighed imaging and fluid-attenuated inversion recovery. Most of the lesions had no enhancement(12/15). Among 7 cases with abnormalities on DWI,hyper-intensity on DWI and hypo-intensity on apparent diffusion coefficient were seen in 3 sudden acute cases and hyper-intensity on DWI and increased apparent diffusion coefficient value in 4 sub-acute or slow onset cases. Three cases showed localized intracranial artery stenosis. In 2 cases,magnetic resonance spectroscopy revealed significant lower N-acetylaspartate peak,higher choline peak,and visible lactate peak or lipid peak. Of 7 cases with follow-up data,3 cases had no change,4 cases had changes including softening lesions(2/4),remitted and relapsed lesions(1/4),and rapid progression of brain atrophy with negative finding on the initial MRI(1/4). Conclusion Routine MRI combined with functional imaging can show the features of HE from different perspectives. Routine MRI shows multifocal or confluent lesions in the white matter,mostly without enhancement,while functional imaging may reveal pathological characteristics of different phases of acute or chronic ischemia and demyelinating changes of HE. Combined with clinical data,MRI can differentiate HE from other diseases based on routine and functional MRI appearances.
Evaluation of the Cardiac Morphologic Alterations Secondary to Autoimmune Thyroid Disorder Using Cardiac Magnetic Resonance Imaging.
Zandieh Shahin,Schuck Linus,Mirzaei Siroos,Haller Joerg,Hergan Klaus,Bernt Reinhard
Journal of thoracic imaging
PURPOSE:Thyroid functional disease is associated with clinically significant cardiovascular changes. The aim of this study was to assess changes in the cardiac magnetic resonance imaging of patients with autoimmune thyroid disorders (AITs). MATERIALS AND METHODS:Forty patients with AIT (12 men, 28 women; age range, 20 to 82 y; mean age, 59 y) were identified and included in our study. In addition, 20 controls (12 men, 8 women; age range, 21 to 76 y; mean age, 50 y) without AIT or cardiac disorders were included. RESULTS:In patients with AIT, the mean value calculated for the end diastolic volume was 161.2 mL, the mean end systolic volume value was 95.3 mL, and the mean left ventricular ejection fraction value was 45.2%. In comparing AIT patients with the control group, we found a significant difference in the end systolic volume, ejection fraction, stroke index, cardiac output, cardiac index, and left ventricular diameter (P<0.05). CONCLUSIONS:We conclude that our data show that there is a correlation between thyroid function and cardiac function, as evaluated with cardiac magnetic resonance imaging. This can be useful in the diagnosis of cardiovascular changes associated with AIT.