Synthetic MRI of the lumbar spine at 3.0 T: feasibility and image quality comparison with conventional MRI

Background Synthetic magnetic resonance imaging (MRI), which can generate multiple morphologic MR images as well as quantitative maps from a single sequence, is not widely used in the spine at 3.0 T. Purpose To investigate the feasibility of synthetic MRI of the lumbar spine in clinical practice at 3.0 T. Material and Methods Eighty-four patients with lumbar diseases underwent conventional T1-weighted images, T2-weighted images, short-tau inversion recovery (STIR) images, and synthetic MRI of the lumbar spine at 3.0 T. The quantitative and qualitative image quality and agreement for detection of spinal lesions between conventional and synthetic MRI were compared by two radiologists. Results The signal-to-noise ratios of synthetic MRI showed an inferior image quality in the vertebrae and disc, whereas were higher for spinal canal and fat on the synthetic T1-weighted, T2-weighted, and STIR images. The contrast-to-noise ratios of the synthetic MRI was superior to conventional sequences, except for the vertebrae–disc contrast-to-noise ratio on T1-weighted imaging ( P = 0.005). Image quality assessments showed that synthetic MRI had greater STIR fat suppression ( P < 0.001) and fluid brightness ( P = 0.014), as well as higher degree of artifacts ( P < 0.001) and worse spatial resolution ( P = 0.002). The inter-method agreements for detection of spinal lesions were substantial to perfect (kappa, 0.614–0.925). Conclusion Synthetic MRI is a feasible method for lumbar spine imaging in a clinical setting at 3.0-T MR. It provides morphologic sequences with acceptable image quality, good agreement with conventional MRI for detection of spinal lesions and quantitative image maps with a slightly shorter acquisition time compared with conventional MRI.

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Improved fat-suppression homogeneity with mDIXON turbo spin echo (TSE) in pediatric spine imaging at 3.0 T

Acta Radiologica ◽

10.1177/0284185117690424 ◽

2017 ◽

Vol 58 (11) ◽

pp. 1386-1394 ◽

Cited By ~ 7

Author(s):

Amber L Pokorney ◽

Jonathan M Chia ◽

Cory M Pfeifer ◽

Jeffrey H Miller ◽

Houchun H Hu

Keyword(s):

Image Quality ◽

Spin Echo ◽

Fat Suppression ◽

Diagnostic Image Quality ◽

Pediatric Spine ◽

Turbo Spin Echo ◽

Diagnostic Image ◽

Turbo Spin ◽

Spine Imaging ◽

3.0 T

Background Robust fat suppression remains essential in clinical MRI to improve tissue signal contrast, minimize fat-related artifacts, and enhance image quality. Purpose To compare fat suppression between mDIXON turbo spin echo (TSE) and conventional frequency-selective and inversion-recovery methods in pediatric spine MRI. Material and Methods Images from T1-weighted (T1W) and T2-weighted (T2W) TSE sequences coupled with conventional methods and the mDIXON technique were compared in 36 patients (5.8 ± 5.4 years) at 3.0 T. Images from 42 pairs of T1W (n = 16) and T2W (n = 26) scans were acquired. Two radiologists reviewed the data and rated images using a three-point scale in two categories, including the uniformity of fat suppression and overall diagnostic image quality. The Wilcoxon rank-sum test was used to compare the scores. Results The Cohen’s kappa coefficient for inter-rater agreement was 0.69 (95% confidence interval [CI], 0.56–0.83). Images from mDIXON TSE were considered superior in fat suppression ( P < 0.01) in 22 (rater 1) and 25 (rater 2) cases, respectively. In 13 (rater 1) and 11 (rater 2) cases, mDIXON TSE demonstrated improved diagnostic image quality ( P < 0.01). In three cases, fat suppression was superior using inversion-recovery and likewise in one case mDIXON had poorer image diagnostic quality. Lastly, mDIXON and conventional fat-suppression methods performed similarly in 17 (rater 1) and 14 (rater 2) cases, and yielded equal diagnostic image quality in 28 (rater 1) and 30 (rater 2) cases. Conclusion Robust fat suppression can be achieved with mDixon TSE pediatric spine imaging at 3.0 T and should be considered as a permanent replacement of traditional methods, in particular frequency-selective techniques.

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Lumbar spine radiographs — is it time for widespread adoption of posteroanterior projection?

British Journal of Radiology ◽

10.1259/bjr.20190386 ◽

2019 ◽

Vol 92 (1103) ◽

pp. 20190386

Author(s):

Christopher Green ◽

Guru Karnati ◽

Katharine Thomson ◽

Ashok Subramanian

Keyword(s):

Lumbar Spine ◽

Image Quality ◽

Effective Dose ◽

Acquisition Time ◽

Reference Image ◽

Patient Study ◽

Spine Radiography ◽

Widespread Adoption ◽

Spine Radiograph ◽

Spine Radiographs

Objective: Phantom studies and a prior patient study have shown up to 53% effective dose reduction when lumbar spine radiographs are acquired posteroanterior (PA) instead of anteroposterior (AP). Since November 2017, Taunton and Somerset NHS Foundation Trust has acquired all standing lumbar spine radiographs PA. The aim of this study was to locally evaluate dose and image quality in both projections and survey current UK practice. Methods: 80 outpatients having a standing lumbar spine radiograph (40 AP; 40 PA) had their dose–area product recorded at a constant KV and focus film distance. Effective dose was calculated using PCXMC software. Each blinded radiograph was scored against an optimal reference image using European Guidelines criteria. The data were analyzed using Mann–Whitney U tests and linear regression. Eighty radiologists nationally were sent an anonymous survey to establish their current practice. Results: A lumbar spine radiograph acquired PA instead of AP reduced effective dose by 41% (p < 0.001) with no difference in image quality (p = 0.9). 21 radiologists completed our survey and only 1 NHS Trust is currently using PA. Conclusion: PA lumbar spine radiography reduces patient radiation exposure with no affect on image quality, acquisition time or cost. The majority of NHS Trusts nationally are still using AP and it is time to standardize to PA. Advances in knowledge: This patient study provides further good evidence of how reduction in exposure to ionizing radiation can be achieved in lumbar spine radiography and more widespread adoption of PA protocol could improve patient safety.

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OPTIMAL COLLIMATION SIGNIFICANTLY IMPROVES LUMBAR SPINE RADIOGRAPHY

Radiation Protection Dosimetry ◽

10.1093/rpd/ncaa057 ◽

2020 ◽

Vol 189 (4) ◽

pp. 420-427

Author(s):

Anamaria Pazanin ◽

Damijan Skrk ◽

Jessica C O'Driscoll ◽

Mark F McEntee ◽

Nejc Mekis

Keyword(s):

Lumbar Spine ◽

Image Quality ◽

Absorbed Dose ◽

Field Size ◽

Organ Doses ◽

Dose Area Product ◽

Spine Radiography ◽

Spine Imaging ◽

Radiosensitive Organs ◽

Area Product

Abstract Purpose To determine the influence of optimal collimation during lumbar spine radiography on radiation dose and image quality. Material and methods 110 lumbar spine patients were split into two groups—the first imaged with standard collimation and the second with optimal collimation. Body mass index, image field size, exposure conditions and dose area product were measured. Effective and absorbed organ doses were calculated. Image quality was assessed. Results Optimal collimation reduced the primary field by up to 40%. The effective dose was reduced by 48% for the AP projection, while no differences were found for the LAT projection due to incorrect positioning of the central beam with standard collimation. The absorbed dose to selected radiosensitive organs decreased by 41 and 10% in the AP and LAT projections, respectively. Image quality for the LAT projection improved by 24% and maintained for the AP projection. Conclusion Optimal collimation in lumbar spine imaging significantly influences patient exposure to radiation.

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Compressed Sensing in Parallel MRI: A Review

International Journal of Image and Graphics ◽

10.1142/s0219467822500383 ◽

2021 ◽

pp. 2250038

Author(s):

Rafiqul Islam ◽

Md Shafiqul Islam ◽

Muhammad Shahin Uddin

Keyword(s):

Compressed Sensing ◽

Imaging Technique ◽

Reconstruction Algorithm ◽

Acquisition Time ◽

Reconstruction Algorithms ◽

Parallel Mri ◽

Image Domain ◽

Conventional Mri ◽

Magnetic Resonance Imaging Mri ◽

Space Data

Magnetic resonance imaging (MRI) is a dynamic and safe imaging technique in medical imaging. Recently, parallel MRI (pMRI) is widely used for accelerating conventional MRI. Both frequency and image domain-based reconstructions are the most attractive methods for generating the image from multi-channel k-space data. Compressed sensing (CS) is a recently used procedure to reduce the acquisition time of conventional MRI. This reduction is achieved by taking fewer measurements from the fully sampled k-space data. Therefore, applying the CS technique in pMRI is the most emerging way for further improving the acquisition time that is a tremendous research interest. However, as the phase encoding plane may be perpendicular or parallel to the coil elements plane, finding the exact domain for CS in pMRI reconstruction is a major challenging issue. In this work, the application of the CS technique in pMRI in both domains is investigated. Later some widely used methodologies are presented as the nonlinear reconstruction algorithm of CS in pMRI. Finally, a discussion is performed based on CS in pMRI to perceive the reality of different reconstruction algorithms at a glance for finding preferred methodologies.

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Using an Office-Based, Dedicated Extremity MRI Scanner for Depicting Important Structures in Common Wrist Pathologies: A Pilot Comparison with a Conventional MRI Scanner

Journal of Wrist Surgery ◽

10.1055/s-0040-1715799 ◽

2020 ◽

Author(s):

Qi Yin ◽

Radu A. Manoliu ◽

Jayant R. Kichari ◽

Marco J. P. F. Ritt

Keyword(s):

Image Quality ◽

Diagnostic Value ◽

Participant Satisfaction ◽

Conventional Mri ◽

Significant Difference ◽

Magnetic Resonance Imaging Mri ◽

The Right ◽

Carpal Ligaments ◽

Score Point

Abstract Background Compared with the conventional magnetic resonance imaging (MRI), dedicated MRI scanners are more accessible. Images of a dedicated 1.0-T MRI specifically developed for the hand and wrist were compared with images of a conventional 1.5-T MRI. Methods Paired images of the right wrist were randomized and separately graded by two experienced radiologists for the quality of anatomical details, including the triangular fibrocartilage complex, carpal ligaments, intercarpal cartilage, median and ulnar nerves, overall image quality, and artifacts. Interrater reliability was measured with the percentage of exact agreement and agreement within a range of ± 1 score point. Participant experience of undergoing the examination in both MRI scanners was evaluated using a questionnaire. Results The overall image quality of all sequences was considered to be moderate to high. In 25 of 38 paired images, no statistically significant difference was found between the MRI scanners. Ten scores were found to be in favor of the dedicated extremity MRI. Within a range of ± 1 score point, the extremity MRI and the conventional MRI demonstrated an interrater agreement of 67 to 100% and 70 to 100%, respectively. Among the respondents of the questionnaire, the extremity MRI scored better for participant satisfaction when compared with the conventional MRI. Conclusions In healthy volunteers, the dedicated extremity MRI generally is similar or superior to the conventional MRI in the depiction of anatomical structures of the wrists, image quality, and artifacts, and significantly scored better on participant satisfaction. Future clinical studies should focus on defining the diagnostic value of the extremity MRI in wrist pathologies.

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Systematic Analysis and Review of Magnetic Resonance Imaging (MRI) Reconstruction Techniques

Current Medical Imaging Formerly Current Medical Imaging Reviews ◽

10.2174/1573405616666210105125542 ◽

2021 ◽

Vol 16 ◽

Author(s):

Penta Anil Kumar ◽

R. Gunasundari ◽

R. Aarthi

Keyword(s):

Magnetic Resonance Imaging ◽

Magnetic Resonance ◽

Optimization Technique ◽

Motion Artifacts ◽

Reconstruction Technique ◽

Resonance Imaging ◽

Research Gaps ◽

Conventional Mri ◽

Mri Reconstruction ◽

Magnetic Resonance Imaging Mri

Background: Magnetic Resonance Imaging (MRI) plays an important role in the field of medical diagnostic imaging as it poses non-invasive acquisition and high soft-tissue contrast. However, the huge time is needed for the MRI scanning process that results in motion artifacts, degrades image quality, misinterpretation of data, and may cause uncomfortable to the patient. Thus, the main goal of MRI research is to accelerate data acquisition processing without affecting the quality of the image. Introduction: This paper presents a survey based on distinct conventional MRI reconstruction methodologies. In addition, a novel MRI reconstruction strategy is proposed based on weighted Compressive Sensing (CS), Penalty-aided minimization function, and Meta-heuristic optimization technique. Methods: An illustrative analysis is done concerning adapted methods, datasets used, execution tools, performance measures, and values of evaluation metrics. Moreover, the issues of existing methods and the research gaps considering conventional MRI reconstruction schemes are elaborated to obtain improved contribution for devising significant MRI reconstruction techniques. Results: The proposed method will reduce conventional aliasing artifacts problems, may attain lower Mean Square Error (MSE), higher Peak Signal-to-Noise Ratio (PSNR), and Structural SIMilarity (SSIM) index. Conclusion: The issues of existing methods and the research gaps considering conventional MRI reconstruction schemes are elaborated to devising an improved significant MRI reconstruction technique.

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Can diffusion and T2 star-weighted magnetic resonance imaging aid in the diagnosis of ectopic endometrium?

Egyptian Journal of Radiology and Nuclear Medicine ◽

10.1186/s43055-021-00513-1 ◽

2021 ◽

Vol 52 (1) ◽

Author(s):

Mariam Raafat ◽

Soha H. Talaat ◽

Salma M. Abdelghaffar ◽

Engy A. Ali

Keyword(s):

Magnetic Resonance Imaging ◽

Magnetic Resonance ◽

Statistical Significance ◽

P Value ◽

Large Sample Size ◽

Resonance Imaging ◽

Conventional Mri ◽

Patient Will ◽

Magnetic Resonance Imaging Mri ◽

Ectopic Endometrium

Abstract Background Endometriosis is a common gynecologic disorder characterized by the implantation of the endometrial tissue ectopically outside the endometrial cavity. It affects about 10% of females at the childbearing period and is estimated to be present up to 20–50% in women complaining of infertility. While laparoscopy is considered the mainstay for diagnosis, magnetic resonance imaging (MRI) is recognized as a useful tool for definitive diagnosis, pre-surgical planning, and determining whether the patient will require multi-specialty involvement. The aim of this study is to evaluate the performance of MRI with the addition of diffusion-weighted imaging (DWI) and T2 star (T2*) to conventional MRI, for the accurate assessment of ectopic endometrium. Results Endometriotic lesions that showed diffusion restriction on DWI were 80.7%, and 96.1% of the endometriotic lesions had signal voids on the T2*W sequence, whereas only 65.4% of the lesions had typical signal intensities on T1WI and T2WI. Diagnostic performance of the MRI examination was improved by the use of the diffusion sequence and better improved by the T2* sequence, compared to the conventional MR protocol sensitivity (SE) = 96.12% and specificity (SP) = 85.7% in T2*-weighted images, SE = 80.7% and SP = 71.4% in DWI, and SE = 65.4% and SP = 71.4% in conventional MRI. P value for conventional MRI was 0.1, which is of no statistical significance (p < 0.05). P value for DWI was 0.016, which is statistically significant (p < 0.05). P value for T2*WI was 0.001, which is more statistically significant (p < 0.05) and could be adequately correlated with laparoscopy. Conclusion DWI and T2* significantly increase MRI diagnostic accuracy by allowing the detection of the hemorrhagic character of the endometriotic lesions. Studies with a large sample size are needed to confirm that they can replace invasive laparoscopy for the diagnosis of endometriosis.

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Quantitative T2 mapping accelerated by GRAPPATINI for evaluation of muscles in patients with myositis

British Journal of Radiology ◽

10.1259/bjr.20190109 ◽

2019 ◽

Vol 92 (1102) ◽

pp. 20190109 ◽

Cited By ~ 3

Author(s):

Fengdan Wang ◽

Haiping Zhang ◽

Chanyuan Wu ◽

Qian Wang ◽

Bo Hou ◽

...

Keyword(s):

T2 Mapping ◽

Quantitative Information ◽

Thigh Muscle ◽

Mapping Technique ◽

Acquisition Time ◽

T2 Relaxation ◽

Muscle Enzymes ◽

Scanning Time ◽

Conventional Mri ◽

Thigh Muscles

Objective: Dermatomyositis (DM) and polymyositis (PM) make up the largest group of potentially treatable myopathies and require early diagnosis. This study investigates whether the edema of thigh muscles in DM/PM can be quantitatively assessed by a novel accelerated T2 mapping technique—GRAPPATINI. Methods: Three conventional MR sequences and GRAPPATINI accelerated T2 mapping of bilateral thighs from 20 patients (7 DM and 13 PM) and 10 healthy volunteers were prospectively carried out on a 3 T MR scanner. Afterwards, T2 values of 477 thigh muscles from the patients and the healthy controls were manually measured. In addition, the correlations between T2 values and serum muscle enzymes in patients were also analyzed. Results: The new GRAPPATINI technique made quantitative T2 mapping of bilateral thighs feasible with a scanning time of only 2 min 18 s. Moreover, GRAPPATINI-generated T2 values of muscles from patients were markedly higher than those from healthy subjects (p < 0.001). GRAPPATINI accelerated T2 mapping appeared a more sensitive technique in that some DM/PM muscles appearing normal per conventional MRI had increased T2 relaxation time. Furthermore, GRAPPATINI-generated T2 values of DM/PM thigh muscles positively correlated with serum enzyme levels (p < 0.001), which reflected the severity of myopathy. Conclusion: GRAPPATINI can significantly shorten acquisition time of T2 mapping and may potentially be applied clinically in DM and PM. Advances in knowledge: GRAPPATINI acceleration makes T2 mapping feasible in clinical practice in providing quantitative information regarding thigh muscle inflammation in DM and PM.

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