Contrast-enhanced MRI Studies Research Articles

Dynamic Contrast-Enhanced MRI.

Dynamic contrast-enhanced MRI in pre-clinical imaging allows the in-vivo monitoring of vascular, physiological properties in normal and diseased tissue. There is considerable variation in the methods employed owing to the different questions that can be asked and answered about the physiologic alterations as well as morphologic changes in tissue. Here we review the typical decisions in the design and execution of a dynamic contrast-enhanced MRI study in mice although the findings can easily be transferred to other species. Emphasis is placed on highlighting the many pitfalls that wait for the unaware pre-clinical MRI practitioner and that go often unmentioned in the abundant literature dealing with dynamic contrast-enhanced MRI in animal models.

Magnetic-Resonance Tomography for Anthropometric Value of Kidneys and Adrenals in Prognosis Efficiency of Renal Sympathetic Denervation in Patients with Treatment-Resistant Hypertension

Aim: to evaluate the possible role of contrast-enhanced MRI studies of the kidneys in prognosis of clinical effect of the renal denervation treatment of the resistant hypertension.Material and methods. 24 patients (57.8 ± 8.75 years) with resistant hypertension were included, in everybody the radiofrequency ablation (RFA) of the sympathetic nerves of renal arteries was carried out. The average 24-h monitor of the arterial pressure was as 137–210/57–148 mm Hg. The MRI studies were performed using MRI scanner “Titan Vantage” (by “Toshiba Medical Ltd”, with the field induction 1.5 Т). After this the intravenous contrast enhancement has been carried out (with 0.5 М solution, 0.2 ml/Kg), with repeat acquisition of Т1-weighted spin-echo images in3–5 min after contrast injection.Results.MRI was employed for quantitative calculation of renal volumes of cortex, medulla and of kidney as total, as well as of suprarenal’s volume. Significant negative correlation of postoperation decrease of arterial pressure has been detected with both volume of renal cortex, as {Decrease in AP = 42.7–0.35 • (V left kidney)}, and also with mass of the right suprarenal gland as {Decrease in SAP = 16.5–6.78 • • (V right suprarenal)}.Conclusion.The anatomic quantitative data of the preoperativeMRI studies of the kidneys can be employed as prognostic tool in patients referred to the renal denervation treatment of the resistant hypertension.

Characterizing and eliminating errors in enhancement and subtraction artifacts in dynamic contrast-enhanced breast MRI: Chemical shift artifact of the third kind.

To characterize errors in enhancement in breast dynamic contrast-enhanced (DCE) MRI studies as a function of echo time and determine the source of dark band artifacts in clinical subtraction images. Computer simulations, oil and water substitute (methylene chloride), as well as an American College of Radiology quality control phantom were tested. Routine clinical DCE breast MRI study was bracketed with (accelerated) in-phase DCE acquisitions in five patients. Simulation results demonstrated up to -160% suppression of the expected enhancement caused by differential enhancement of fat and water. Two-dimensional gradient-recalled echo and fat-suppressed 3D GRE phantom imaging confirmed the simulation results and showed that fat suppression does not eliminate the artifact. In vivo in-phase DCE images showed increased enhancement consistent with predictions and also confirmed increased spatial blurring on in-phase 3D gradient-recalled echo images. Combined multi-dimensional partial Fourier and parallel imaging provided a time-equivalent in-phase DCE MRI acquisition. Errors in expected enhancement occur in DCE breast MRI subtraction images because of differential enhancement of fat and water and incomplete fat signal suppression. These errors can lead to artificial suppression of enhancement as well as dark band artifacts on subtraction images. These artifacts can be eliminated with a time-equivalent in-phase fat-suppressed 3D gradient-recalled echo sequence. Understanding chemical shift artifact of the third kind, a unique artifact of artificial enhancement suppression in the presence of intravoxel fat and water signal, will aid DCE breast MRI image interpretation. In-phase acquisitions (combined with simultaneous minimum echo time or opposed-phase echoes) may facilitate qualitative, quantitative and longitudinal analysis of contrast enhancement. Magn Reson Med 79:2277-2289, 2018. © 2017 International Society for Magnetic Resonance in Medicine.

Understanding Ktrans: a simulation study based on a multiple-pathway model

The transfer constant Ktrans is commonly employed in dynamic contrast-enhanced MRI studies, but the utility and interpretation of Ktrans as a potential biomarker of tumor vasculature remains unclear. In this study, computer simulations based on a comprehensive tracer kinetic model with multiple pathways was used to provide clarification on the interpretation and application of Ktrans. Tissue concentration-time curves pertaining to a wide range of transport conditions were simulated using the multiple-pathway (MP) model and fitted using the generalized kinetic (GK) and extended GK models. Relationships between Ktrans and plasma flow Fp, vessel permeability PS and extraction rate EFp under various transport conditions were assessed by correlation and regression analysis. Results show that the MP model provides an alternative two-tier interpretation of Ktrans based on the vascular transit time. Ktrans is primarily associated with Fp and EFp respectively, in the slow and rapid vascular transit states, independent of the magnitude of PS. The relative magnitudes of PS and Fp only serve as secondary constraints for which Ktrans can be further associated with EFp and PS in the slow and rapid transit states, respectively.

An adaptive model for rapid and direct estimation of extravascular extracellular space in dynamic contrast enhanced MRI studies.

Extravascular extracellular space (ve ) is a key parameter to characterize the tissue of cerebral tumors. This study introduces an artificial neural network (ANN) as a fast, direct, and accurate estimator of ve from a time trace of the longitudinal relaxation rate, ΔR1 (R1 =1/T1 ), in DCE-MRI studies. Using the extended Tofts equation, a set of ΔR1 profiles was simulated in the presence of eight different signal to noise ratios. A set of gain- and noise-insensitive features was generated from the simulated ΔR1 profiles and used as the ANN training set. A K-fold cross-validation method was employed for training, testing, and optimization of the ANN. The performance of the optimal ANN (12:6:1, 12 features as input vector, six neurons in hidden layer, and one output) in estimating ve at a resolution of 10% (error of ±5%) was 82%. The ANN was applied on DCE-MRI data of 26 glioblastoma patients to estimate ve in tumor regions. Its results were compared with the maximum likelihood estimation (MLE) of ve . The two techniques showed a strong agreement (r=0.82, p<0.0001). Results implied that the perfected ANN was less sensitive to noise and outperformed the MLE method in estimation of ve .

3 Tesla-Diffusion Tensor Imaging in Autosomal Dominant Polycystic Kidney Disease: The Nephrologist's Point of View

Background/Aims: CT, MRI and ultrasound are currently used for screening and follow-up of individuals affected by autosomal dominant polycystic kidney disease (ADPKD). Dynamic contrast-enhanced MRI studies renal perfusion after gadolinium administration, with possible side effects, such as nephrogenic systemic fibrosis. The aim of our study was to evaluate the clinical application of 3 Tesla (3T)-diffusion tensor image (DTI) in ADPKD patients, correlating its parameters, such as fractional anisotropy (FA), and apparent diffusion coefficient (ADC) with kidney function tests. Methods: Eight ADPKD patients and 6 healthy volunteers (HS) were enrolled. FA and ADC mean values were calculated. And correlations between DTI-parameters, creatinine and estimated glomerular filtration rate (eGFR) were evaluated. Results: Parenchymal FA was significantly lower in ADPKD than HS (FA: 0.17 ± 0.03 vs. 0.22 ± 0.01; p = 0.02), whereas parenchymal ADC was higher in patients than controls (2.48 (×10^-3) ± 0.16 vs. 2.28 (×10^-3) ± 0.09), but a statistically significant difference was not achieved (p = 0.27). Direct correlations were revealed between eGFR and FA (r = 0.82; p = 0.0003), whereas an inverse correlation was found with creatinine (r = -0.77; p = 0.001). Similarly, ADC closely correlated with creatinine (r = 0.79; p = 0.0006) and eGFR (r = -0.620; p = 0.01). Conclusion: 3T-DTI is a promising radiological tool that could be used by nephrologists to evaluate ADPKD patients, highlighting early micro-structure alterations, without side effects and contrast agent administration.

Volume‐normalized transfer constant as an imaging biomarker for chronic inflammatory arthritis: A dynamic contrast enhanced MRI study

Proper diagnosis and treatment of rheumatoid arthritis are extremely important to optimize treatment outcomes. Dynamic contrast-enhanced MRI (DCE-MRI) may be used as a biomarker to detect inflammatory changes in synovial joints and to discriminate active and inactive stages of the disease. The aim of this study was to investigate vascular permeability changes associated with inflammatory arthritis progression and its treatment. Arthritis was induced in DBA/1J mice by immunization with type-II collagen emulsified in complete Freund's adjuvant. Severity of arthritis was monitored using the clinical arthritis index. MR images of mice were obtained at different stages of arthritis progression and at 3 weeks after methotrexate treatment. Immunohistochemical staining using an anti-CD31 antibody was used to assess vessel density. Volume-normalized transfer constant increased progressively until the active stage of arthritis was reached, and thereafter declined gradually. The pattern of volume-normalized transfer constant changes quantified using DCE-MRI correlated with vascular densities and immunohistochemical findings. Furthermore, volume-normalized transfer constant and densities decreased significantly in a dose-dependent manner after treatment with methotrexate. Volume-normalized transfer constant assessed by DCE-MRI can be used as an imaging biomarker for tracking disease progression and for monitoring therapeutic efficacy in inflammatory arthritis. Magn Reson Med 76:926-934, 2016. © 2016 Wiley Periodicals, Inc.

Multimodal imaging findings in normal-appearing white matter of leucoaraiosis: a review

Leucoaraiosis (LA), also referred to as white matter hyperintensities (WMHs), are usually seen as patchy or confluent hyperintense areas on T2-weighted or fluid-attenuated inversion recovery MRI in the elderly. It...

Natural history of liver imaging reporting and data system category 4 nodules in MRI.

The purpose of this study was to characterize the MR imaging features and outcomes of liver imaging reporting and data system (LI-RADS) category 4 (LR4) nodules, with an emphasis on upgrade to category 5 (LR5) and development of contraindications to curative therapy. Institutional review board approval was obtained for this retrospective, dual-institutional Health Insurance Portability and Accountability Act-compliant study. The requirement for informed consent was waived. Contrast-enhanced MRI studies performed on patients with cirrhosis were retrospectively assessed using LI-RADS 2014 by at least two readers. All nodules were individually evaluated to determine their major imaging features at diagnosis, and follow-up data were used to determine the associated imaging outcomes. One hundred eighty-one untreated LR4 nodules in 139 patients had adequate imaging and follow-up for inclusion in the study. Most (61% [111/181]) of these demonstrated arterial phase hyperenhancement, washout, and diameter less than 20mm. During the follow-up period (median 163days), 31% (56/181) of the nodules upgraded to LR5, 40% (73/181) remained stable, and 29% (52/181) downgraded. Of the nodules that upgraded, 61% (34/56) increased their size category and 54% (30/56) developed newly visualized capsules. No LR4 nodules developed venous invasion, satellites nodules, or new intrahepatic or extrahepatic metastatic disease. 75% (42/56) of the nodules that upgraded to LR5 did so within 6months. Approximately one-third of LR4 nodules upgrade to LR5, and the short-term risk of developing venous invasion or metastasis is very low.

Recommendations of the ESSR Arthritis Subcommittee for the Use of Magnetic Resonance Imaging in Musculoskeletal Rheumatic Diseases.

This article presents the recommendations of the European Society of Musculoskeletal Radiology Arthritis Subcommittee regarding the standards of the use of MRI in the diagnosis of musculoskeletal rheumatic diseases. The recommendations discuss (1) the role of MRI in current classification criteria of musculoskeletal rheumatic diseases (including early diagnosis of inflammation, disease follow-up, and identification of disease complications); (2) the impact of MRI on the diagnosis of axial and peripheral spondyloarthritis, rheumatoid arthritis, and juvenile spondyloarthritis; (3) MRI protocols for the axial and peripheral joints; (4) MRI interpretation and reporting for axial and peripheral joints; and finally, (5) methods for assessing MR images including quantitative, semiquantitative, and dynamic contrast-enhanced MRI studies.

MRI of a syrinx: is contrast material always necessary?

The workup of a syrinx often includes contrast-enhanced MRI to exclude the presence of an underlying mass. The diagnostic yield of performing these additional contrast-enhanced sequences is not well defined in the literature. We hypothesized that T2-weighted imaging alone could reliably exclude the presence of a syrinx-associated mass without the need for contrast-enhanced imaging sequences in all cases. Two independent readers retrospectively analyzed contrast-enhanced MRI studies of 87 consecutive patients with syringes. The presence or absence of an associated spinal cord mass was determined using only T2-weighted imaging. The imaging features considered positive for a possible syrinx-associated lesion on T2-weighted imaging were syrinx nodularity, syrinx septations, and a spinal cord signal intensity abnormality or a mass separate from the syrinx. The size of the syrinx was also recorded. Using contrast-enhanced sequences as the reference standard, statistical analysis was performed to determine the accuracy of T2-weighted imaging in detecting a syrinx-associated mass. Of the 87 cases of syrinx, there were 23 mass lesions, 11 Chiari malformations, three spinal cord contusions, and 50 idiopathic syringes. Using T2-weighted imaging alone, readers detected no findings suspicious for a syrinx-associated mass in 55 cases and detected findings suspicious for a mass in 32 of 87 cases. Reader sensitivity for an underlying mass lesion was 100%; specificity, 86%; positive predictive value, 72%; and negative predictive value, 100%. Interreader agreement was excellent (κ = 0.88). Syrinx size showed a positive correlation with the presence of a mass lesion (p < 0.0001). T2-weighted imaging alone appears to have a high sensitivity and high negative predictive value in evaluating for a syrinx-associated mass, and contrast-enhanced imaging may not be required for the workup of a syrinx.

AB1001 A Cloud-Based Enterprise Image Analysis Platform for Musculoskeletal Diseases

BackgroundMR Imaging is a key to objective analysis of joint diseases. The detection of erosions on radiograms, which only show structural changes, might be delayed for more than a year...

Phase I Trial of Preoperative Chemoradiation plus Sorafenib for High-Risk Extremity Soft Tissue Sarcomas with Dynamic Contrast-Enhanced MRI Correlates

We conducted a phase I trial of the addition of sorafenib to a chemoradiotherapy regimen in patients with high-risk (intermediate/high grade, >5 cm) extremity soft tissue sarcoma undergoing limb salvage surgery. We conducted a correlative study of quantitative dynamic contrast-enhanced MRI (DCE-MRI) to assess response to treatment. Patients were treated at increasing dose levels of sorafenib (200 mg daily, 400 mg daily, 400 mg twice daily) initiated 14 days before three preoperative and three postoperative cycles of epirubicin/ifosfamide. Radiation (28 Gy) was administered during cycle 2 with epirubicin omitted. The primary objective was to determine the maximum tolerated dose (MTD) of sorafenib. DCE-MRI was conducted at baseline, after 2 weeks of sorafenib, and before surgery. The imaging data were subjected to quantitative pharmacokinetic analyses. Eighteen subjects were enrolled, of which 16 were evaluable. The MTD of sorafenib was 400 mg daily. Common grade 3-4 adverse events included neutropenia (94%), hypophosphatemia (75%), anemia (69%), thrombocytopenia (50%), and neutropenic fever/infection (50%). Of note, 38% developed wound complications requiring surgical intervention. The rate of ≥95% histopathologic tumor necrosis was 44%. Changes in DCE-MRI biomarker ΔK(trans) after 2 weeks of sorafenib correlated with histologic response (R(2) = 0.67, P = 0.012) at surgery. The addition of sorafenib to preoperative chemoradiotherapy is feasible and warrants further investigation in a larger trial. DCE-MRI detected changes in tumor perfusion after 2 weeks of sorafenib and may be a minimally invasive tool for rapid assessment of drug effect in soft tissue sarcoma.

Registration of dynamic contrast‐enhanced MRI of the common carotid artery using a fixed‐frame template‐based squared‐difference method

This study examines template-based squared-difference registration for motion correction in dynamic contrast-enhanced (DCE) MRI studies of the carotid artery wall and compares the results of fixed-frame template-based registration with a previously proposed consecutive-frame registration method. Ten T1-weighted black-blood, turbo spin-echo DCE-MRI studies of the carotid artery wall were used to test template-based squared-difference registration. An intermediate image from each series was selected as the fixed-frame template for registration. Squared-difference minimization was used to align each image and template. Time-intensity curves generated from data aligned with template-based squared-difference registration were compared with gold standard curves created by drawing regions of interest on each image in the series. The results were also compared with unregistered data and data after consecutive-frame squared-difference registration. An analysis of variance test of root mean-square error values between gold standard curve and curves from unregistered data and data registered with consecutive-frame and fixed-frame template-based methods was significant (P < 0.005) with template-based squared-difference registration producing curves that most closely matched the gold standard. A fixed-frame template-based squared-difference registration method was proposed and validated for alignment of DCE-MRI of carotid arteries.

Characterisation and evaluation of paramagnetic fluorine labelled glycol chitosan conjugates for 19F and 1H magnetic resonance imaging

Medium molecular weight glycol chitosan conjugates have been prepared, linked by an amide bond to paramagnetic Gd(III), Ho(III) and Dy(III) macrocyclic complexes in which a trifluoromethyl reporter group is located 6.5 Å from the paramagnetic centre. The faster relaxation of the observed nucleus allows modified pulse sequences to be used with shorter acquisition times. The polydisperse materials have been characterised by gel permeation chromatography, revealing an average molecular weight on the order of 13,800 (Gd), 14,600 (Dy) and 16,200 (Ho), consistent with the presence of 8.5, 9.5 and 13 complexes, respectively. The gadolinium conjugate was prepared for both a q = 1 monoamide tricarboxylate conjugate (r1p 11.2 mM(-1) s(-1), 310 K, 1.4 T) and a q = 0 triphosphinate system, and conventional contrast-enhanced proton MRI studies at 7 T were undertaken in mice bearing an HT-29 or an HCT-116 colorectal tumour xenograft (17 μmol/kg). Enhanced contrast was observed following injection in the tail vein in tumour tissue, with uptake also evident in the liver and kidney with a tumour-to-liver ratio of 2:1 at 13 min, and large amounts in the kidney and bladder consistent with predominant renal clearance. Parallel experiments observing the (19)F resonance in the holmium conjugate complex using a surface coil did not succeed owing to its high R2 value (750 Hz, 7 T). However, the fluorine signal in the dysprosium triphosphinate chitosan conjugate [R1/R2 = 0.6 and R1 = 145 Hz (7 T)] was sharper and could be observed in vivo at -65.7 ppm, following intravenous tail vein injection of a dose of 34 μmol/kg.

Paramagnetic liposomes for molecular MRI and MRI‐guided drug delivery

Liposomes are a versatile class of nanoparticles with tunable properties, and multiple liposomal drug formulations have been clinically approved for cancer treatment. In recent years, an extensive library of gadolinium (Gd)-containing liposomal MRI contrast agents has been developed for molecular and cellular imaging of disease-specific markers and for image-guided drug delivery. This review discusses the advances in the development and novel applications of paramagnetic liposomes in molecular and cellular imaging, and in image-guided drug delivery. A high targeting specificity has been achieved in vitro using ligand-conjugated paramagnetic liposomes. On targeting of internalizing cell receptors, the effective longitudinal relaxivity r1 of paramagnetic liposomes is modulated by compartmentalization effects. This provides unique opportunities to monitor the biological fate of liposomes. In vivo contrast-enhanced MRI studies with nontargeted liposomes have shown the extravasation of liposomes in diseases associated with endothelial dysfunction, such as tumors and myocardial infarction. The in vivo use of targeted paramagnetic liposomes has facilitated the specific imaging of pathophysiological processes, such as angiogenesis and inflammation. Paramagnetic liposomes loaded with drugs have been utilized for therapeutic interventions. MR image-guided drug delivery using such liposomes allows the visualization and quantification of local drug delivery.

Enhancement of Ovarian Malignancy on Clinical Contrast Enhanced MRI Studies

Purpose. To assess if there is a significant difference in enhancement of high grade serous carcinoma of the ovary compared with other ovarian malignancies on clinically performed contrast enhanced MRI studies. Methods. In this institutional-review–board-approved study, two radiologists reviewed contrast enhanced MRI scans in 37 patients with ovarian cancer. Readers measured the signal intensity (SI) of ovarian mass and gluteal fat pre- and postcontrast administration. Percentage enhancement (PE) was calculated as [(post-pre)/precontrast SI] × 100. Results. Pathology revealed 19 patients with unilateral and 18 patients with bilateral malignancies for a total of 55 malignant ovaries-high grade serous carcinoma in 25/55 ovaries (45%), other epithelial carcinomas in 12 ovaries (22%), nonepithelial cancers in 8 ovaries (14%), and borderline tumors in 10 ovaries (18%). Enhancement of high grade serous carcinoma was not significantly different from other invasive ovarian malignancies (Reader 1 P = 0.865; Reader 2 P = 0.353). Enhancement of invasive ovarian malignancies was more than borderline tumors but did not reach statistical significance (Reader 1P = 0.102; Reader 2 P = 0.072). Conclusion. On clinically performed contrast enhanced MRI studies, enhancement of high grade serous ovarian carcinoma is not significantly different from other ovarian malignancies.

Observer Study of a Prototype Clinical Decision Support System for Breast Cancer Diagnosis Using Dynamic Contrast-Enhanced MRI

The purpose of this article is to evaluate the performance of radiologists using a prototype clinical decision support system to diagnose and manage patients with breast cancer based on dynamic contrast-enhanced MRI studies. The study was conducted with three breast radiologists and two breast imaging fellows who gave patient treatment recommendations and confidence ratings, both without and with computer aid. The computer aid presented similar cases from a retrieval database of 192 lesions (96 malignant and 96 benign) for a test set of 97 mass lesions (46 malignant and 51 benign). The performance of each observer was quantified by receiver operating characteristic analysis. The radiologists' confidence in their recommendations was analyzed with respect to the query case pathologic diagnosis, perceived usefulness of the similar cases, and the accuracy of the computer in retrieving cases of the correct diagnosis. The statistical significance in the performance measure differences was determined by using a two-tailed Student t test for paired data. For each observer, the area under the receiver operating characteristic curve did not change significantly with the use of the computer aid (from a mean of 0.8 to a mean of 0.8; p = 0.61). The average confidence of three of the five observers increased significantly with the computer aid (from 5.9 to 6.3 [p < 0.001], from 7.0 to 7.2 [p = 0.04], and from 4.4 to 5.4 [p < 0.001], respectively). The confidence change of the radiologists was more frequent and larger for malignant lesions where the computer was correct. However, for benign lesions, even when the computer was correct, the confidence of the radiologists did not necessarily change. The presentation of similar cases reinforced radiologists' confidence rating in the diagnosis of malignant lesions; however, it did not change their confidence rating for benign lesions or reduce the number of unnecessary biopsies in managing patients with breast cancer using dynamic contrast-enhanced MRI under the limited study conditions.

116: Quantitative analysis of microvascular obstruction is bestly related to clinical prognosis than clinical markers at a 1 year follow-up: a contrast-enhanced MRI study

To evaluate the clinical prognostic value of a cardiac magnetic resonance (CMR) assessment soon after a first ST-segment elevation myocardial infarction (STEMI). Clinical factors such as gender, age, blood pressure, heart beat, heart and renal failure have already been described as related to poor clinical prognosis at follow-up. For now, the prognostic value and weight of CMR parametersis not well-defined. We followed for 1 year up to 168 consecutive patients with a firstSTEMI treated with primary angioplasty. We performed CMR at day 5±2 and 3months to assess LV volumes. We used delayed enhancement imaging to assess the infarct size and the presence of MVO. We defined severe MVO as MVO extent being superior to its median value (2,82 gr). 13 major adverse cardiac events (MACE) including 2 cardiac deaths, 1 nonfatal myocardial infarctions, 8 readmissions for heart failure and 2 stroke were documented. In univariate analysis, the MACE was related to age, creatin kinase peak, heart failure, MVO and LV volumes. In a complete multivariate analysis, age (hazard ratio 1.075, p=0.003), end-diastolic LV volume (HR 0.74, p=0.017), end-systolic LV volume (HR 1.046, p=0.039), MVO presence (HR 8.867, p=0.041; Log rank=9.195, p=0.002) and severe MVO (HR 9.906, p=0.002; Log rank=18.090, p<0.001) were the only independent prognostic variables. Of note, clinical marker such as heart failure was strongly related to age and found as non significant in multivariate analysis. A comprehensive CMR assessment is useful for stratifying risk soon after STEMI; baseline LV volumes and severe MVO are the stronger independent prognosis factor. This result supports the clinical interest of a quantitative assessment of MVO.

Effects of early corticosteroid treatment on magnetic resonance imaging and ultrasonography findings in giant cell arteritis

To compare the impact of initial corticosteroid treatment on high-resolution MRI and colour-coded duplex sonography (CCDS) findings in patients with GCA (temporal). Sensitivity and specificity of CCDS and high-resolution contrast-enhanced MRI studies of 59 patients with suspected GCA were retrospectively analysed. Patients were grouped according to the duration of steroid treatment before imaging: 0-1 day, 2-4 days and >4 days. In 41 patients, imaging results were compared with findings of temporal artery biopsy (TAB). Sixty-one per cent (36/59) of patients were diagnosed with GCA. TAB findings were positive in 59% (24/41). The compared results of TAB sensitivity of CCDS and MRI under steroid treatment of 0-1 day were 92% and 90%, 2-4 days 80% and 78% and >4 days 50% and 80%, respectively. The compared results of the final clinical diagnosis sensitivity of CCDS and MRI under steroid treatment of 0-1 day was 88% and 85%, 2-4 days 50% and 64% and >4 days 50% and 56%, respectively. Sensitivity of a first-time CCDS or an MRI for detection of GCA rapidly decreases under corticosteroid treatment. Therefore imaging of patients with suspected GCA should be performed as soon as possible, preferably within the first days of treatment.