Julie Dicarlo | Stanford University (original) (raw)

Papers by Julie Dicarlo

Research paper thumbnail of P258 MEASUREMENT OF KNEE ALIGNMENT ON FIXED-FLEXION RADIOGRAPHS USING REGRESSION TO BONE SHAFT EDGES

Osteoarthritis and Cartilage, 2006

in the measurement of minimum joint space width (JSW) and a better sensitivity to change in OA th... more in the measurement of minimum joint space width (JSW) and a better sensitivity to change in OA than the conventional standing anteroposterior (AP) view of the knee. Both radiographic protocols use identical subject knee positioning however, the LS protocol requires the alignment of the medial tibial plateau with the Xray beam through fluoroscopic guidance. A head to head comparison of both radiographic views has not been published. This study evaluated the long-term reproducibility of the measurement of JSW in normal knees and the sensitivity to change in knees with OA for both radiographic methods. Methods: One knee from 63 patients with knee OA (KL ≥ 2) and from 55 aged-and sex-matched control subjects (KL = 0) were serially radiographed the same day using both the LS and the FF protocols, at baseline and 1 year later. Minimum Joint Space Width (mJSW) of the medial femoro-tibial joint was measured with a computerized program (Holy's, Lyon, France). Medial tibial plateau (MTP) alignment was assessed by measurement of the interim distance (IRD) representing the distance between the anterior and posterior rims of the MTP. Results: Mean (SD) change from baseline in mJSW in normal knees was 0.02 (0.29) mm (p=0.12) and 0.06 (0.23) mm (p=0.09) in LS and FF radiographs, respectively. Mean (SD) Joint Space Narrowing (JSN) in OA knees was 0.21 (0.40) mm (p<0.0001) and 0.03 (0.37) mm (p=0.57) in LS and FF radiographs, respectively. Overall the mean (SD) IRD was significantly smaller (p<0.0001) in LS compared to FF radiographs, 0.97(0.65) mm versus 1.83 (1.09) mm at baseline and 0.88 (0.58) mm versus 1.84 (1.09) mm at one year, respectively. Conclusions: No change in mJSW was observed in normal knees similarly in both radiograph techniques. The significant JSN over one year in LS compared to FF radiographs may be attributed to a tighter MTP alignment.

Research paper thumbnail of Variable Density Excitation Pulses in One-Shot Fourier Velocity Encoding for Valve Flow Imaging

Research paper thumbnail of Application of Small Surface Coil for Cancer Detection in Laryngeal Cartilage

Introduction Laryngeal cancer afflicts 13,000 people per year. Most patients undergo intensive ra... more Introduction Laryngeal cancer afflicts 13,000 people per year. Most patients undergo intensive radiation and chemotherapy to preserve the larynx, but those patients who fail therapy usually require total laryngectomy, with devastating effects on the patient's quality of life. Detection of early cartilage invasion is critical in determining the optimum treatment modality for these patients [1]. Cartilage invasion leads to the failure of radiation and chemotherapy to control invasive disease. Early detection of cartilage invasion could allow patients to undergo partial laryngectomy, allowing preservation of the majority of the vocal apparatus while still eradicating disease. High resolution imaging of the cartilage may increase our ability to detect subtle cartilage invasion. MR imaging of supraglottic lesions using an anterior neck surface coil has demonstrated tumor-induced cartilage signal changes [2]. Improved resolution in this region can be obtained using smaller surface coi...

Research paper thumbnail of FRI0495 Magnetic resonance imaging may be helpful in predicting long term efficacy of certolizumab pegol in patients with active rheumatoid arthritis

Annals of the Rheumatic Diseases

Research paper thumbnail of Pre-Treatment Whole Blood Gene Expression Is Associated with 14-Week Response Assessed by Dynamic Contrast Enhanced Magnetic Resonance Imaging in Infliximab-Treated Rheumatoid Arthritis Patients

PLoS ONE, 2014

Approximately 30% of rheumatoid arthritis patients achieve inadequate response to anti-TNF biolog... more Approximately 30% of rheumatoid arthritis patients achieve inadequate response to anti-TNF biologics. Attempts to identify molecular biomarkers predicting response have met with mixed success. This may be attributable, in part, to the variable and subjective disease assessment endpoints with large placebo effects typically used to classify patient response. Sixty-one patients with active RA despite methotrexate treatment, and with MRI-documented synovitis, were randomized to receive infliximab or placebo. Blood was collected at baseline and genome-wide transcription in whole blood was measured using microarrays. The primary endpoint in this study was determined by measuring the transfer rate constant (Ktrans) of a gadolinium-based contrast agent from plasma to synovium using MRI. Secondary endpoints included repeated clinical assessments with DAS28(CRP), and assessments of osteitis and synovitis by the RAMRIS method. Infliximab showed greater decrease from baseline in DCE-MRI Ktrans of wrist and MCP at all visits compared with placebo (P&amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;lt;0.001). Statistical analysis was performed to identify genes associated with treatment-specific 14-week change in Ktrans. The 256 genes identified were used to derive a gene signature score by averaging their log expression within each patient. The resulting score correlated with improvement of Ktrans in infliximab-treated patients and with deterioration of Ktrans in placebo-treated subjects. Poor responders showed high expression of activated B-cell genes whereas good responders exhibited a gene expression pattern consistent with mobilization of neutrophils and monocytes and high levels of reticulated platelets. This gene signature was significantly associated with clinical response in two previously published whole blood gene expression studies using anti-TNF therapies. These data provide support for the hypothesis that anti-TNF inadequate responders comprise a distinct molecular subtype of RA characterized by differences in pre-treatment blood mRNA expression. They also highlight the importance of placebo controls and robust, objective endpoints in biomarker discovery. ClinicalTrials.gov NCT01313520.

Research paper thumbnail of Flow-independent angiography of the hand with 3D balanced SSFP imaging

Introduction: MR hand angiography is clinically useful in the diagnosis of conditions such as Ray... more Introduction: MR hand angiography is clinically useful in the diagnosis of conditions such as Raynaud's disease and peripheral vascular occlusion. Balanced steady-state freeprecession (SSFP) imaging is SNR-efficient and adequate for high-resolution flow-independent angiography (FIA) without the need for injected contrast agent . However, fat gives bright signal obscuring vascular structure. Air-tissue interfaces create SSFP signal nulls/voids. In recent work, flowindependent angiograms of the foot have been acquired with 3D Balanced SSFP imaging [1], where fat has been suppressed using phase-sensitive SSFP reconstruction [2] with complexsum SSFP . Bands created by air-tissue interfaces result in failure of phase-sensitive SSFP reconstruction. Moreover, complex-sum SSFP degrades contrast-to-noise ratio while doubling the scan time and increasing vulnerability to patient movement. In this work, a single SSFP acquisition is exploited along with a phase-sensitive SSFP reconstruction for high-resolution hand angiography. The hand is packed in susceptibility-matching material (Kaopectate) to distance the air-tissue interface. This method significantly reduces banding artifacts within the imaging region and improves the robustness of fat-water separation. Methods: The sequence uses a spoiled inversion-recovery to null signal from long-T1 fluids, followed by T2-preparation (90°x, 180°y, 180°y, -90 x ) [4] to generate blood/muscle contrast [1]. A linear ramp catalyzation follows to prevent transient oscillations in the balanced SSFP acquisition . The ordering of phase encodes is a centric square-spiral allowing the low-spatial frequencies to have the desired contrast . However, during the acquisition the initial magnetization-prepared contrast is gradually replaced by the steady-state contrast, especially for high-spatial frequencies. Square-spiral phase encodes are interleaved to reduce this problem with the above module repeated for each interleaf with a recovery time between each. The 3D Balanced SSFP FIA sequence was implemented on a 1.5 T GE Signa Excite scanner with CV/i gradients. Two different protocols were used. For 0.7 mm isotropic resolution with an 8-channel knee coil, subjects were scanned with the following parameters: α = 75 o , TR/TE = 4.6/2.3 ms, 16 cm FOV, 125 kHz BW, inversion time = 2 s, T2-Prep time = 80 ms, a 10-excitation catalyzation, 6 interleaves and a 10 sec recovery time. The total scan time was 2:12. The following scan parameters were changed for 0.5 mm isotropic resolution: TR/TE = 4.8/2.3 ms, 10 interleaves and no fluidsuppression inversion-recovery (to compensate for reduced SNR at higher resolution). The total scan time was 3:40. Phase-sensitive SSFP fat-water separation was carried out for each of the 8 channels. A sum-of-squares combination of the multi-channel data was followed by a maximum-intensity projection to visualize the vessels. Results: The 0.7 mm isotropic-resolution images are shown in , without and with the susceptibility-matching material used to keep the air-tissue boundary away from the skin. There are certain locations where the phase-sensitive SSFP reconstruction fails to correctly detect fat (arrows). When the susceptibility matching is carried out, fat suppression works better and removes fat at the problematic locations. Field maps without and with the susceptibility-matching material are displayed in . The peak-to-peak variation of off-resonance frequencies is reduced from ±94.6 Hz to ±54.5 Hz with the susceptibility matching. shows the 0.5 mm isotropic-resolution angiograms with some synovial fluid around the joints because long-T1 fluid-suppression has been omitted to achieve higher SNR. High resolution images have less partial volume effect and hence give better depiction of small vessels. Conclusion: We have demonstrated high-resolution flow-independent angiograms of the hand using magnetization-prepared 3D Balanced SSFP combined with phase-sensitive fat-water separation. We have shown that susceptibility-matching material prevents the formation of SSFP bands within the imaging region, enhancing fat-separation robustness. Finally, we have shown that increasing resolution to 0.5 mm helps mitigate partial volume effects. Hand angiograms can be acquired in less than 4 minutes, without the need for intravenous contrast agent.

Research paper thumbnail of SAT0492 Treatment Effects Measured by Dynamic Contrast Enhanced MRI and Ramris for Rheumatoid Arthritis

Annals of the Rheumatic Diseases, 2013

Research paper thumbnail of Comparison of the Genant-modified Sharp and van der Heijde-modified Sharp scoring methods for radiographic assessment in rheumatoid arthritis

International Journal of Clinical Rheumatology, 2011

Research paper thumbnail of The effects of tocilizumab on osteitis, synovitis and erosion progression in rheumatoid arthritis: results from the ACT-RAY MRI substudy

Research paper thumbnail of 343 FIXED-LOCATION JOINT SPACE WIDTH MEASUREMENT INCREASES SENSITIVITY TO CHANGE IN OSTEOARTHRITIS

Osteoarthritis and Cartilage, 2007

be underestimated because of the relative insensitivity of the MTP view to JSN [4]. The SF-AP vie... more be underestimated because of the relative insensitivity of the MTP view to JSN [4]. The SF-AP view, in which knee flexion and rotation are the means to achieve optimal visualization of the joint space under fluoroscopy, yielded AAA measurements that were more subject to change over time than those in the MTP view. However, while change in AAA ≥2°valgus in the SF-AP view was associated with widening of the medial joint space, varus change of the same magnitude was not accompanied by more rapid loss of medial JSW.

Research paper thumbnail of Variable-density one-shot fourier velocity encoding

Magnetic Resonance in Medicine, 2005

In areas of highly pulsatile and turbulent flow, real-time imaging with high temporal, spatial, a... more In areas of highly pulsatile and turbulent flow, real-time imaging with high temporal, spatial, and velocity resolution is essential. The use of 1D Fourier velocity encoding (FVE) was previously demonstrated for velocity measurement in real time, with fewer effects resulting from off-resonance. The application of variable-density sampling is proposed to improve velocity measurement without a significant increase in readout time or the addition of aliasing artifacts. Two sequence comparisons are presented to improve velocity resolution or increase the velocity field of view (FOV) to unambiguously measure velocities up to 5 m/s without aliasing. The results from a tube flow phantom, a stenosis phantom, and healthy volunteers are presented, along with a comparison of measurements using Doppler ultrasound (US). The studies confirm that variable-density acquisition of k z -k v space improves the velocity resolution and FOV of such data, with the greatest impact on the improvement of FOV to include velocities in stenotic ranges. Magn Reson Med 54: 645-655, 2005.

Research paper thumbnail of Magnetic Resonance Imaging in Rheumatoid Arthritis Clinical Trials: Emerging Patterns Based on Recent Experience

The Journal of Rheumatology, 2011

This article updates the work and results of the OMERACT MRI in RA Working Group as presented at ... more This article updates the work and results of the OMERACT MRI in RA Working Group as presented at the OMERACT 7 meeting in May 2004, focusing on the development of the EULAR-OMER-ACT rheumatoid arthritis magnetic resonance imaging reference image atlas, and on areas for future research. (J Rheumatol 2005;32:2462-4)

Research paper thumbnail of Evaluating joint-space narrowing and cartilage loss in rheumatoid arthritis by using MRI

Arthritis Research & Therapy, 2012

Introduction: Magnetic resonance imaging (MRI) has been shown to be superior to radiography (XR) ... more Introduction: Magnetic resonance imaging (MRI) has been shown to be superior to radiography (XR) for assessing synovitis, osteitis, and bone erosion in rheumatoid arthritis (RA), particularly in clinical trials. However, relatively little has been reported on the ability of MRI to evaluate articular cartilage loss, or joint-space narrowing (JSN), in the hands and wrists. In a previous study, we adapted the nine-point Genant-modified Sharp XR-JSN score for use with MRI (MRI-JSN). In this study, we compare MRI-JSN with XR-JSN by using images from two multicenter clinical trials. Methods: Baseline XR and 1.5-Tesla MR images of one hand and wrist from each of 47 subjects with RA enrolled in one of two multicenter clinical trials were evaluated by using the XR-JSN and MRI-JSN methods by a single radiologist experienced in the two methods. Radiographs and MR images were read independently on different occasions.

Research paper thumbnail of Monitoring cartilage loss in the hands and wrists in rheumatoid arthritis with magnetic resonance imaging in a multi-center clinical trial: IMPRESS (NCT00425932)

Arthritis Research & Therapy, 2013

Introduction: Magnetic resonance imaging (MRI) is increasingly being used in clinical trials of r... more Introduction: Magnetic resonance imaging (MRI) is increasingly being used in clinical trials of rheumatoid arthritis (RA) because of its superiority over x-ray radiography (XR) in detecting and monitoring change in bone erosion, osteitis and synovitis. However, in contrast to XR, the MRI scoring method that was used in most clinical trials did not include cartilage loss. This limitation has been an obstacle to accepting MRI as a potential alternative to XR in clinical trials. Cross-sectional studies have shown MRI to be sensitive for cartilage loss in the hands and wrist; although, longitudinal sensitivity to change has not yet been confirmed. In this study we examined the ability of MRI to monitor change in cartilage loss in patients with RA in a multi-site clinical trial setting. Methods: Thirty-one active RA patients from a clinical trial (IMPRESS) who were randomized equally into treatment with either rituximab + methotrexate or placebo + methotrexate had MRI of the dominant hand/wrist at baseline, 12 weeks and 24 weeks at 3 clinical sites in the US. Twenty-seven of these patients also had XR of both hands/ wrists and both feet at baseline and 24 weeks. One radiologist scored all XR images using the van der Heijdemodified Sharp method blinded to visit order. The same radiologist scored MR images for cartilage loss using a previously validated 9-point scale, and bone erosion using the Outcome Measures in Rheumatology Clinical Trials (OMERACT) RA MRI Score (RAMRIS) blinded to visit order and XR scores. Data from the two treatment arms were pooled for this analysis. Results: Mean MRI cartilage score increased at 12 and 24 weeks, and reached statistical significance at 24 weeks. XR total Sharp score, XR erosion score and XR joint-space narrowing (JSN) score all increased at 24 weeks, but only XR total Sharp score increased significantly. Conclusions: To our knowledge, this is the first publication of a study demonstrating MRI's ability to monitor cartilage loss in a multi-site clinical trial. Combined with MRI's established performance in monitoring bone erosions in RA, these findings suggest that MRI may offer a superior alternative to XR in multi-site clinical trials of RA.

Research paper thumbnail of An oral Syk kinase inhibitor in the treatment of rheumatoid arthritis: A three-month randomized, placebo-controlled, phase II study in patients with active rheumatoid arthritis that did not respond to biologic agents

Arthritis & Rheumatism, 2011

Objective. To assess the efficacy and safety of R788 (fostamatinib disodium), an inhibitor of spl... more Objective. To assess the efficacy and safety of R788 (fostamatinib disodium), an inhibitor of spleen tyrosine kinase (Syk), in patients with active rheumatoid arthritis (RA) that did not respond to biologic therapies.

Research paper thumbnail of Impact of intravenous abatacept on synovitis, osteitis and structural damage in patients with rheumatoid arthritis and an inadequate response to methotrexate: the ASSET randomised controlled trial

Annals of the Rheumatic Diseases, 2013

Research paper thumbnail of P258 MEASUREMENT OF KNEE ALIGNMENT ON FIXED-FLEXION RADIOGRAPHS USING REGRESSION TO BONE SHAFT EDGES

Osteoarthritis and Cartilage, 2006

in the measurement of minimum joint space width (JSW) and a better sensitivity to change in OA th... more in the measurement of minimum joint space width (JSW) and a better sensitivity to change in OA than the conventional standing anteroposterior (AP) view of the knee. Both radiographic protocols use identical subject knee positioning however, the LS protocol requires the alignment of the medial tibial plateau with the Xray beam through fluoroscopic guidance. A head to head comparison of both radiographic views has not been published. This study evaluated the long-term reproducibility of the measurement of JSW in normal knees and the sensitivity to change in knees with OA for both radiographic methods. Methods: One knee from 63 patients with knee OA (KL ≥ 2) and from 55 aged-and sex-matched control subjects (KL = 0) were serially radiographed the same day using both the LS and the FF protocols, at baseline and 1 year later. Minimum Joint Space Width (mJSW) of the medial femoro-tibial joint was measured with a computerized program (Holy's, Lyon, France). Medial tibial plateau (MTP) alignment was assessed by measurement of the interim distance (IRD) representing the distance between the anterior and posterior rims of the MTP. Results: Mean (SD) change from baseline in mJSW in normal knees was 0.02 (0.29) mm (p=0.12) and 0.06 (0.23) mm (p=0.09) in LS and FF radiographs, respectively. Mean (SD) Joint Space Narrowing (JSN) in OA knees was 0.21 (0.40) mm (p<0.0001) and 0.03 (0.37) mm (p=0.57) in LS and FF radiographs, respectively. Overall the mean (SD) IRD was significantly smaller (p<0.0001) in LS compared to FF radiographs, 0.97(0.65) mm versus 1.83 (1.09) mm at baseline and 0.88 (0.58) mm versus 1.84 (1.09) mm at one year, respectively. Conclusions: No change in mJSW was observed in normal knees similarly in both radiograph techniques. The significant JSN over one year in LS compared to FF radiographs may be attributed to a tighter MTP alignment.

Research paper thumbnail of Variable Density Excitation Pulses in One-Shot Fourier Velocity Encoding for Valve Flow Imaging

Research paper thumbnail of Application of Small Surface Coil for Cancer Detection in Laryngeal Cartilage

Introduction Laryngeal cancer afflicts 13,000 people per year. Most patients undergo intensive ra... more Introduction Laryngeal cancer afflicts 13,000 people per year. Most patients undergo intensive radiation and chemotherapy to preserve the larynx, but those patients who fail therapy usually require total laryngectomy, with devastating effects on the patient's quality of life. Detection of early cartilage invasion is critical in determining the optimum treatment modality for these patients [1]. Cartilage invasion leads to the failure of radiation and chemotherapy to control invasive disease. Early detection of cartilage invasion could allow patients to undergo partial laryngectomy, allowing preservation of the majority of the vocal apparatus while still eradicating disease. High resolution imaging of the cartilage may increase our ability to detect subtle cartilage invasion. MR imaging of supraglottic lesions using an anterior neck surface coil has demonstrated tumor-induced cartilage signal changes [2]. Improved resolution in this region can be obtained using smaller surface coi...

Research paper thumbnail of FRI0495 Magnetic resonance imaging may be helpful in predicting long term efficacy of certolizumab pegol in patients with active rheumatoid arthritis

Annals of the Rheumatic Diseases

Research paper thumbnail of Pre-Treatment Whole Blood Gene Expression Is Associated with 14-Week Response Assessed by Dynamic Contrast Enhanced Magnetic Resonance Imaging in Infliximab-Treated Rheumatoid Arthritis Patients

PLoS ONE, 2014

Approximately 30% of rheumatoid arthritis patients achieve inadequate response to anti-TNF biolog... more Approximately 30% of rheumatoid arthritis patients achieve inadequate response to anti-TNF biologics. Attempts to identify molecular biomarkers predicting response have met with mixed success. This may be attributable, in part, to the variable and subjective disease assessment endpoints with large placebo effects typically used to classify patient response. Sixty-one patients with active RA despite methotrexate treatment, and with MRI-documented synovitis, were randomized to receive infliximab or placebo. Blood was collected at baseline and genome-wide transcription in whole blood was measured using microarrays. The primary endpoint in this study was determined by measuring the transfer rate constant (Ktrans) of a gadolinium-based contrast agent from plasma to synovium using MRI. Secondary endpoints included repeated clinical assessments with DAS28(CRP), and assessments of osteitis and synovitis by the RAMRIS method. Infliximab showed greater decrease from baseline in DCE-MRI Ktrans of wrist and MCP at all visits compared with placebo (P&amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;lt;0.001). Statistical analysis was performed to identify genes associated with treatment-specific 14-week change in Ktrans. The 256 genes identified were used to derive a gene signature score by averaging their log expression within each patient. The resulting score correlated with improvement of Ktrans in infliximab-treated patients and with deterioration of Ktrans in placebo-treated subjects. Poor responders showed high expression of activated B-cell genes whereas good responders exhibited a gene expression pattern consistent with mobilization of neutrophils and monocytes and high levels of reticulated platelets. This gene signature was significantly associated with clinical response in two previously published whole blood gene expression studies using anti-TNF therapies. These data provide support for the hypothesis that anti-TNF inadequate responders comprise a distinct molecular subtype of RA characterized by differences in pre-treatment blood mRNA expression. They also highlight the importance of placebo controls and robust, objective endpoints in biomarker discovery. ClinicalTrials.gov NCT01313520.

Research paper thumbnail of Flow-independent angiography of the hand with 3D balanced SSFP imaging

Introduction: MR hand angiography is clinically useful in the diagnosis of conditions such as Ray... more Introduction: MR hand angiography is clinically useful in the diagnosis of conditions such as Raynaud's disease and peripheral vascular occlusion. Balanced steady-state freeprecession (SSFP) imaging is SNR-efficient and adequate for high-resolution flow-independent angiography (FIA) without the need for injected contrast agent . However, fat gives bright signal obscuring vascular structure. Air-tissue interfaces create SSFP signal nulls/voids. In recent work, flowindependent angiograms of the foot have been acquired with 3D Balanced SSFP imaging [1], where fat has been suppressed using phase-sensitive SSFP reconstruction [2] with complexsum SSFP . Bands created by air-tissue interfaces result in failure of phase-sensitive SSFP reconstruction. Moreover, complex-sum SSFP degrades contrast-to-noise ratio while doubling the scan time and increasing vulnerability to patient movement. In this work, a single SSFP acquisition is exploited along with a phase-sensitive SSFP reconstruction for high-resolution hand angiography. The hand is packed in susceptibility-matching material (Kaopectate) to distance the air-tissue interface. This method significantly reduces banding artifacts within the imaging region and improves the robustness of fat-water separation. Methods: The sequence uses a spoiled inversion-recovery to null signal from long-T1 fluids, followed by T2-preparation (90°x, 180°y, 180°y, -90 x ) [4] to generate blood/muscle contrast [1]. A linear ramp catalyzation follows to prevent transient oscillations in the balanced SSFP acquisition . The ordering of phase encodes is a centric square-spiral allowing the low-spatial frequencies to have the desired contrast . However, during the acquisition the initial magnetization-prepared contrast is gradually replaced by the steady-state contrast, especially for high-spatial frequencies. Square-spiral phase encodes are interleaved to reduce this problem with the above module repeated for each interleaf with a recovery time between each. The 3D Balanced SSFP FIA sequence was implemented on a 1.5 T GE Signa Excite scanner with CV/i gradients. Two different protocols were used. For 0.7 mm isotropic resolution with an 8-channel knee coil, subjects were scanned with the following parameters: α = 75 o , TR/TE = 4.6/2.3 ms, 16 cm FOV, 125 kHz BW, inversion time = 2 s, T2-Prep time = 80 ms, a 10-excitation catalyzation, 6 interleaves and a 10 sec recovery time. The total scan time was 2:12. The following scan parameters were changed for 0.5 mm isotropic resolution: TR/TE = 4.8/2.3 ms, 10 interleaves and no fluidsuppression inversion-recovery (to compensate for reduced SNR at higher resolution). The total scan time was 3:40. Phase-sensitive SSFP fat-water separation was carried out for each of the 8 channels. A sum-of-squares combination of the multi-channel data was followed by a maximum-intensity projection to visualize the vessels. Results: The 0.7 mm isotropic-resolution images are shown in , without and with the susceptibility-matching material used to keep the air-tissue boundary away from the skin. There are certain locations where the phase-sensitive SSFP reconstruction fails to correctly detect fat (arrows). When the susceptibility matching is carried out, fat suppression works better and removes fat at the problematic locations. Field maps without and with the susceptibility-matching material are displayed in . The peak-to-peak variation of off-resonance frequencies is reduced from ±94.6 Hz to ±54.5 Hz with the susceptibility matching. shows the 0.5 mm isotropic-resolution angiograms with some synovial fluid around the joints because long-T1 fluid-suppression has been omitted to achieve higher SNR. High resolution images have less partial volume effect and hence give better depiction of small vessels. Conclusion: We have demonstrated high-resolution flow-independent angiograms of the hand using magnetization-prepared 3D Balanced SSFP combined with phase-sensitive fat-water separation. We have shown that susceptibility-matching material prevents the formation of SSFP bands within the imaging region, enhancing fat-separation robustness. Finally, we have shown that increasing resolution to 0.5 mm helps mitigate partial volume effects. Hand angiograms can be acquired in less than 4 minutes, without the need for intravenous contrast agent.

Research paper thumbnail of SAT0492 Treatment Effects Measured by Dynamic Contrast Enhanced MRI and Ramris for Rheumatoid Arthritis

Annals of the Rheumatic Diseases, 2013

Research paper thumbnail of Comparison of the Genant-modified Sharp and van der Heijde-modified Sharp scoring methods for radiographic assessment in rheumatoid arthritis

International Journal of Clinical Rheumatology, 2011

Research paper thumbnail of The effects of tocilizumab on osteitis, synovitis and erosion progression in rheumatoid arthritis: results from the ACT-RAY MRI substudy

Research paper thumbnail of 343 FIXED-LOCATION JOINT SPACE WIDTH MEASUREMENT INCREASES SENSITIVITY TO CHANGE IN OSTEOARTHRITIS

Osteoarthritis and Cartilage, 2007

be underestimated because of the relative insensitivity of the MTP view to JSN [4]. The SF-AP vie... more be underestimated because of the relative insensitivity of the MTP view to JSN [4]. The SF-AP view, in which knee flexion and rotation are the means to achieve optimal visualization of the joint space under fluoroscopy, yielded AAA measurements that were more subject to change over time than those in the MTP view. However, while change in AAA ≥2°valgus in the SF-AP view was associated with widening of the medial joint space, varus change of the same magnitude was not accompanied by more rapid loss of medial JSW.

Research paper thumbnail of Variable-density one-shot fourier velocity encoding

Magnetic Resonance in Medicine, 2005

In areas of highly pulsatile and turbulent flow, real-time imaging with high temporal, spatial, a... more In areas of highly pulsatile and turbulent flow, real-time imaging with high temporal, spatial, and velocity resolution is essential. The use of 1D Fourier velocity encoding (FVE) was previously demonstrated for velocity measurement in real time, with fewer effects resulting from off-resonance. The application of variable-density sampling is proposed to improve velocity measurement without a significant increase in readout time or the addition of aliasing artifacts. Two sequence comparisons are presented to improve velocity resolution or increase the velocity field of view (FOV) to unambiguously measure velocities up to 5 m/s without aliasing. The results from a tube flow phantom, a stenosis phantom, and healthy volunteers are presented, along with a comparison of measurements using Doppler ultrasound (US). The studies confirm that variable-density acquisition of k z -k v space improves the velocity resolution and FOV of such data, with the greatest impact on the improvement of FOV to include velocities in stenotic ranges. Magn Reson Med 54: 645-655, 2005.

Research paper thumbnail of Magnetic Resonance Imaging in Rheumatoid Arthritis Clinical Trials: Emerging Patterns Based on Recent Experience

The Journal of Rheumatology, 2011

This article updates the work and results of the OMERACT MRI in RA Working Group as presented at ... more This article updates the work and results of the OMERACT MRI in RA Working Group as presented at the OMERACT 7 meeting in May 2004, focusing on the development of the EULAR-OMER-ACT rheumatoid arthritis magnetic resonance imaging reference image atlas, and on areas for future research. (J Rheumatol 2005;32:2462-4)

Research paper thumbnail of Evaluating joint-space narrowing and cartilage loss in rheumatoid arthritis by using MRI

Arthritis Research & Therapy, 2012

Introduction: Magnetic resonance imaging (MRI) has been shown to be superior to radiography (XR) ... more Introduction: Magnetic resonance imaging (MRI) has been shown to be superior to radiography (XR) for assessing synovitis, osteitis, and bone erosion in rheumatoid arthritis (RA), particularly in clinical trials. However, relatively little has been reported on the ability of MRI to evaluate articular cartilage loss, or joint-space narrowing (JSN), in the hands and wrists. In a previous study, we adapted the nine-point Genant-modified Sharp XR-JSN score for use with MRI (MRI-JSN). In this study, we compare MRI-JSN with XR-JSN by using images from two multicenter clinical trials. Methods: Baseline XR and 1.5-Tesla MR images of one hand and wrist from each of 47 subjects with RA enrolled in one of two multicenter clinical trials were evaluated by using the XR-JSN and MRI-JSN methods by a single radiologist experienced in the two methods. Radiographs and MR images were read independently on different occasions.

Research paper thumbnail of Monitoring cartilage loss in the hands and wrists in rheumatoid arthritis with magnetic resonance imaging in a multi-center clinical trial: IMPRESS (NCT00425932)

Arthritis Research & Therapy, 2013

Introduction: Magnetic resonance imaging (MRI) is increasingly being used in clinical trials of r... more Introduction: Magnetic resonance imaging (MRI) is increasingly being used in clinical trials of rheumatoid arthritis (RA) because of its superiority over x-ray radiography (XR) in detecting and monitoring change in bone erosion, osteitis and synovitis. However, in contrast to XR, the MRI scoring method that was used in most clinical trials did not include cartilage loss. This limitation has been an obstacle to accepting MRI as a potential alternative to XR in clinical trials. Cross-sectional studies have shown MRI to be sensitive for cartilage loss in the hands and wrist; although, longitudinal sensitivity to change has not yet been confirmed. In this study we examined the ability of MRI to monitor change in cartilage loss in patients with RA in a multi-site clinical trial setting. Methods: Thirty-one active RA patients from a clinical trial (IMPRESS) who were randomized equally into treatment with either rituximab + methotrexate or placebo + methotrexate had MRI of the dominant hand/wrist at baseline, 12 weeks and 24 weeks at 3 clinical sites in the US. Twenty-seven of these patients also had XR of both hands/ wrists and both feet at baseline and 24 weeks. One radiologist scored all XR images using the van der Heijdemodified Sharp method blinded to visit order. The same radiologist scored MR images for cartilage loss using a previously validated 9-point scale, and bone erosion using the Outcome Measures in Rheumatology Clinical Trials (OMERACT) RA MRI Score (RAMRIS) blinded to visit order and XR scores. Data from the two treatment arms were pooled for this analysis. Results: Mean MRI cartilage score increased at 12 and 24 weeks, and reached statistical significance at 24 weeks. XR total Sharp score, XR erosion score and XR joint-space narrowing (JSN) score all increased at 24 weeks, but only XR total Sharp score increased significantly. Conclusions: To our knowledge, this is the first publication of a study demonstrating MRI's ability to monitor cartilage loss in a multi-site clinical trial. Combined with MRI's established performance in monitoring bone erosions in RA, these findings suggest that MRI may offer a superior alternative to XR in multi-site clinical trials of RA.

Research paper thumbnail of An oral Syk kinase inhibitor in the treatment of rheumatoid arthritis: A three-month randomized, placebo-controlled, phase II study in patients with active rheumatoid arthritis that did not respond to biologic agents

Arthritis & Rheumatism, 2011

Objective. To assess the efficacy and safety of R788 (fostamatinib disodium), an inhibitor of spl... more Objective. To assess the efficacy and safety of R788 (fostamatinib disodium), an inhibitor of spleen tyrosine kinase (Syk), in patients with active rheumatoid arthritis (RA) that did not respond to biologic therapies.

Research paper thumbnail of Impact of intravenous abatacept on synovitis, osteitis and structural damage in patients with rheumatoid arthritis and an inadequate response to methotrexate: the ASSET randomised controlled trial

Annals of the Rheumatic Diseases, 2013