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Okubo T, Kawasaki K, Harada R, Nagatari T, Matsumoto M, Maru S. [Novel Application of Post-contrast T 1map for Detection of Subendocardial Infarction]. Nihon Hoshasen Gijutsu Gakkai Zasshi 2023; 79:1352-1358. [PMID: 37967944 DOI: 10.6009/jjrt.2023-1384] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2023]
Abstract
In cardiac magnetic resonance (CMR) for myocardial infarction, there have been quite a few cases of obscure image contrast between subendocardial lesion and left ventricular (LV) blood pool on late gadolinium enhancement (LGE) images. This study was motivated by confirmation of usefulness of post-contrast T1map for detection of subendocardial infarction. From June 2017 to May 2018, forty-eight consecutive patients who underwent contrast-enhanced CMR to assess myocardial infarction were reviewed. We measured the contrast ratio (CR) between the infarcted myocardium and LV blood pool on LGE and on post-contrast T1map images, and compared them. The CR (mean±standard deviation) was -0.04±0.11 for LGE images and 0.02±0.04 for post-contrast T1map images (P<0.05). These results suggest that the post-contrast T1map, which uses the difference in T1 value as image contrast rather than magnitude image, can clearly depict the boundary between the infarcted myocardium and LV blood pool. The addition of post-contrast T1map to image interpretation might provide valuable information in the evaluation of subendocardial infarction.
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Affiliation(s)
- Takumi Okubo
- Department of Radiology, Chiba Cerebral and Cardiovascular Center
| | - Kohei Kawasaki
- Department of Radiology, Chiba Cerebral and Cardiovascular Center
| | - Rena Harada
- Department of Radiology, Chiba Cerebral and Cardiovascular Center
| | - Tsutomu Nagatari
- Department of Radiology, Chiba Cerebral and Cardiovascular Center
| | | | - Shigenori Maru
- Department of Radiology, Chiba Cerebral and Cardiovascular Center
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Zhu Y, Wang C, Su S, Qiu Z, Yan Z, Liang D, Wang Y, Wang H. High resolution single-shot myocardial imaging using bSSFP with wave encoding. Med Phys 2023; 50:7039-7048. [PMID: 37219842 DOI: 10.1002/mp.16471] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2022] [Revised: 04/03/2023] [Accepted: 04/03/2023] [Indexed: 05/24/2023] Open
Abstract
BACKGROUND Single-shot balanced steady-state free precession (bSSFP) sequence is widely used in cardiac imaging. However, the limited scan time in one heartbeat greatly hinders its spatial resolution compared to the segmented acquisition mode. Therefore, a highly accelerated single-shot bSSFP imaging technology is needed for clinical use. PURPOSE To develop and evaluate a wave-encoded bSSFP sequence with high acceleration rates for single-shot myocardial imaging. METHODS The proposed Wave-bSSFP method is implemented by adding a sinusoidal wave gradient in the phase encoding direction during the readout of bSSFP sequence. Uniform undersampling is used for acceleration. Its performance was first validated via phantom studies by comparison with conventional bSSFP. Then it was evaluated in volunteer studies via anatomical imaging, T2 -prepared bSSFP, and T1 mapping in in-vivo cardiac imaging. All methods were compared with accelerated conventional bSSFP reconstructed using iterative SENSE and compressed sensing (CS), to demonstrate the advantage of wave encoding in suppressing the noise amplification and artifacts induced by acceleration. RESULTS The proposed Wave-bSSFP method achieved a high acceleration factor of 4 for single-shot acquisitions. The proposed method showed lower average g-factors than bSSFP, and fewer blurring artifacts than CS reconstruction. The Wave-bSSFP with R = 4 achieved higher spatial and temporal resolutions compared with the conventional bSSFP with R = 2 in several applications such as T2 -prepared bSSFP and T1 mapping, and could be applied in systolic imaging. CONCLUSION Wave encoding can be used to highly accelerate 2D bSSFP imaging with single-shot acquisitions. Compared with the conventional bSSFP sequence, the proposed Wave-bSSFP method can effectively reduce the g-factor and aliasing artifacts in cardiac imaging.
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Affiliation(s)
- Yanjie Zhu
- Paul C. Lauterbur Research Center for Biomedical Imaging, Shenzhen Institute of Advanced Technology, Chinese Academy of Sciences, Shenzhen, China
| | - Che Wang
- Paul C. Lauterbur Research Center for Biomedical Imaging, Shenzhen Institute of Advanced Technology, Chinese Academy of Sciences, Shenzhen, China
- Department of Biomedical Engineering, Chongqing University of Technology, Chongqing, China
| | - Shi Su
- Paul C. Lauterbur Research Center for Biomedical Imaging, Shenzhen Institute of Advanced Technology, Chinese Academy of Sciences, Shenzhen, China
| | - Zhilang Qiu
- Paul C. Lauterbur Research Center for Biomedical Imaging, Shenzhen Institute of Advanced Technology, Chinese Academy of Sciences, Shenzhen, China
| | - Zhonghong Yan
- Department of Biomedical Engineering, Chongqing University of Technology, Chongqing, China
| | - Dong Liang
- Paul C. Lauterbur Research Center for Biomedical Imaging, Shenzhen Institute of Advanced Technology, Chinese Academy of Sciences, Shenzhen, China
| | - Yining Wang
- Department of Radiology, State Key Laboratory of Complex Severe and Rare Diseases, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China
| | - Haifeng Wang
- Paul C. Lauterbur Research Center for Biomedical Imaging, Shenzhen Institute of Advanced Technology, Chinese Academy of Sciences, Shenzhen, China
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Malkawi L, Hassan R, Alshrouf MA, Al-Ryalat N, AlRyalat SA. The impact of COVID-19 on open access publishing in radiology and nuclear medicine: an in-depth analysis. J Med Life 2023; 16:967-973. [PMID: 37900061 PMCID: PMC10600658 DOI: 10.25122/jml-2023-0075] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2023] [Accepted: 06/13/2023] [Indexed: 10/31/2023] Open
Abstract
In response to the COVID-19 pandemic, numerous initiatives have been implemented to ensure open access availability of COVID-19-related articles to make published articles accessible for anyone. This study aimed to assess the impact of the COVID-19 pandemic on open-access publishing in radiology and nuclear medicine. We conducted a comprehensive analysis of articles and reviews published in these fields during the COVID-19 publishing era using the Web of Science database. We analyzed several indicators between COVID-19 and non-COVID-19 related articles, including the number and percentage of open-access articles, the top ten cited articles, and the number of reviews. In total, 67,100 articles were published in radiology and nuclear medicine between January 2020 and June 2022. Among those, more than half (51.1%) were open-access articles. Among these publications, 2,336 were COVID-19-related, and 64,764 were non-COVID-19-related. However, articles related to COVID-19 had an open access rate of 91.5%, compared to only 49.6% of the non-COVID-19-related articles. Moreover, COVID-19-related articles had a higher percentage of highly cited and hot papers compared to articles not related to COVID-19. Moreover, most highly cited studies were related to chest computerized tomography (CT) scan findings in COVID-19 patients. The findings emphasize the significant proportion of open access COVID-19-related publications in radiology and nuclear medicine, facilitating widespread and timely access to everyone.
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Affiliation(s)
- Lna Malkawi
- Department of Radiology, University of Jordan, Amman, Jordan
| | - Reem Hassan
- Family Medicine, Primary Health Care Corporation, Doha, Qatar
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Oh H, Yim Y, Chung MS, Byun JS. Wave-controlled aliasing in parallel imaging (Wave-CAIPI): Accelerating speed for the MRI-based diagnosis of enhancing intracranial lesions compared to magnetization-prepared gradient echo. PLoS One 2023; 18:e0285089. [PMID: 37146026 PMCID: PMC10162559 DOI: 10.1371/journal.pone.0285089] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2021] [Accepted: 04/14/2023] [Indexed: 05/07/2023] Open
Abstract
PURPOSE We aimed to validate the diagnostic performance of accelerated post-contrast magnetization-prepared rapid gradient-echo (MPRAGE) using wave-controlled aliasing in parallel imaging (Wave-CAIPI) for enhancing intracranial lesions, compared with conventional MPRAGE. METHODS A total of 233 consecutive patients who underwent post-contrast Wave-CAIPI and conventional MPRAGE (scan time: 2 min 39 s vs. 4 min 30 s) were retrospectively evaluated. Two radiologists independently assessed whole images for the presence and diagnosis of enhancing lesions. The diagnostic performance for non-enhancing lesions, quantitative parameters (diameter of enhancing lesions, signal-to-noise ratio [SNR], contrast-to-noise ratio [CNR], and contrast rate), qualitative parameters (grey-white matter differentiation and conspicuity of enhancing lesions), and image qualities (overall image quality and motion artifacts) were also surveyed. The weighted kappa and percent agreement were used to evaluate the diagnostic agreement between the two sequences. RESULTS Wave-CAIPI MPRAGE achieved significantly high agreement for the detection (98.7%[460/466], κ = 0.965) and diagnosis (97.8%[455/466], κ = 0.955) of enhancing intracranial lesions with conventional MPRAGE in pooled analysis. Detection and diagnosis of non-enhancing lesions (97.6% and 96.9% agreement), and diameter of enhancing lesions (P>0.05) also demonstrated high agreements between two sequences. Although Wave-CAIPI MPRAGE show lower SNR (P<0.01) than conventional MRAGE, it fulfilled comparable CNR (P = 0.486) and higher contrast rate (P<0.01). The qualitative parameters show similar value (P>0.05). The overall image quality was slightly poor, however, motion artifacts were better in Wave-CAIPI MPRAGE (both P = 0.005). CONCLUSION Wave-CAIPI MPRAGE provides reliable diagnostic performance for enhancing intracranial lesions within half of the scan time compared with conventional MPRAGE.
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Affiliation(s)
- Hyunji Oh
- Chung-Ang University Hospital, Chung-Ang University College of Medicine, Seoul, Republic of Korea
| | - Younghee Yim
- Chung-Ang University Hospital, Chung-Ang University College of Medicine, Seoul, Republic of Korea
| | - Mi Sun Chung
- Chung-Ang University Hospital, Chung-Ang University College of Medicine, Seoul, Republic of Korea
| | - Jun Soo Byun
- Chung-Ang University Hospital, Chung-Ang University College of Medicine, Seoul, Republic of Korea
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5
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Lee EJ, Kim MG, Chung MS, Kim SO, Byun JS, Yim Y. Diagnosis of intracranial lesions using accelerated 3D T1 MPRAGE with wave-CAIPI technique: comparison with conventional 3D T1 MPRAGE. Sci Rep 2022; 12:21930. [PMID: 36536040 PMCID: PMC9763340 DOI: 10.1038/s41598-022-25725-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2022] [Accepted: 12/05/2022] [Indexed: 12/23/2022] Open
Abstract
We aimed to evaluate the agreement in the diagnosis of intracranial lesions between conventional pre-contrast 3D T1 magnetization-prepared rapid gradient echo (MPRAGE) and wave-CAIPI (wave-controlled aliasing in parallel imaging) MPRAGE. Institutional review board approval was obtained and informed consent was waived for this retrospective study. We included 149 consecutive patients who had undergone brain MR with both conventional MPRAGE (scan time: 5 min 42 s) and wave-CAIPI MPRAGE (scan time: 2 min 44 s) from February to June 2018. All images were independently reviewed by two radiologists for the diagnosis of intracranial lesion and scored image quality using visual analysis. One technician measured signal-to-noise ratio. The agreement for diagnosis of intracranial lesion was calculated, and the intra- and interobserver agreements were analyzed by using kappa value. For the diagnosis of intracranial lesion, the conventional and wave-CAIPI MPRAGE demonstrated 99.7% of agreement (297 of 298) in the pooled analysis with very good agreement (k = 0.994). Intra- and inter-observer agreement showed very good (k > 0.9 in all) and good (k > 0.75) agreement, respectively. In the quantitative analysis, the signal-to-noise ratio had no difference (P > 0.05 for all). The overall image quality was poorer in images of wave-CAIPI MPRAGE (P < 0.001), but motion artifact had no difference between two sequences (P = 0.06). Compared to conventional MPRAGE, pre-contrast 3D T1 wave-CAIPI MPRAGE achieved higher agreement for the diagnosis of intracranial lesions and reduced the scan time by approximately 50%.
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Affiliation(s)
- Eun Jung Lee
- Department of Radiology, Human Medical Imaging & Intervention Center, Seoul, Korea ,grid.254224.70000 0001 0789 9563Department of Radiology, Chung-Ang University Hospital, Chung-Ang University College of Medicine, 102 Heukseok-Ro, Dongjak-Gu, Seoul, Republic of Korea
| | - Min Gu Kim
- grid.254224.70000 0001 0789 9563Department of Radiology, Chung-Ang University Hospital, Chung-Ang University College of Medicine, 102 Heukseok-Ro, Dongjak-Gu, Seoul, Republic of Korea
| | - Mi Sun Chung
- Department of Radiology, Human Medical Imaging & Intervention Center, Seoul, Korea ,grid.254224.70000 0001 0789 9563Department of Radiology, Chung-Ang University Hospital, Chung-Ang University College of Medicine, 102 Heukseok-Ro, Dongjak-Gu, Seoul, Republic of Korea
| | - Seon-Ok Kim
- grid.267370.70000 0004 0533 4667Department of Clinical Epidemiology and Biostatistics, Asan Medical Center, University of Ulsan College of Medicine, 86 Asanbyeongwon-Gil, Songpa-Gu, Seoul, Republic of Korea
| | - Jun Soo Byun
- Department of Radiology, Human Medical Imaging & Intervention Center, Seoul, Korea ,grid.254224.70000 0001 0789 9563Department of Radiology, Chung-Ang University Hospital, Chung-Ang University College of Medicine, 102 Heukseok-Ro, Dongjak-Gu, Seoul, Republic of Korea
| | - Younghee Yim
- grid.254224.70000 0001 0789 9563Department of Radiology, Chung-Ang University Hospital, Chung-Ang University College of Medicine, 102 Heukseok-Ro, Dongjak-Gu, Seoul, Republic of Korea
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Gao R, Liu J, Zhu H. Diagnostic Value of Magnetic Resonance Susceptibility-Weighted Imaging Scanning in Different Types of Early Prostate Cancer. SCANNING 2022; 2022:4884646. [PMID: 35795617 PMCID: PMC9152370 DOI: 10.1155/2022/4884646] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 04/13/2022] [Revised: 05/04/2022] [Accepted: 05/10/2022] [Indexed: 06/15/2023]
Abstract
To investigate the cost of MRI-sensitive imaging (SWI) for early-stage prostate cancer. In 2019, the research group included a total of 60 leukemia patients, all of whom were diagnosed with prostate-specific antigen (PSA). According to the range of PSA values, they were group A (18 cases), group A 0-44 mg/ml (18 cases), and group B 4-1010 mg/ml (26 cases). 10 mg/ml was divided into C group (16 cases). Another 60 patients with benign prostatic hyperplasia treated at the same time served as a control group. All patients underwent sensitive MRI scanning, followed by diagnostic and clinical evaluation of weighted MRI scanning to diagnose various types of prostate cancer. The results showed that there was no difference in Ve levels among the three groups (P > 0.05); the SUSE score and Ktrans and Kep levels of the patients in group C were higher in groups B, A, and A (P < 0.05). In patients with early leukemia, SUSE score was significantly correlated with Ktrans and Kep levels (P < 0.05), but not with Ve and P > 0.05 levels. Magnetic resonance imaging can be used to diagnose prostate cancer. It can differentiate and diagnose different types of prostate cancer early. This is important for evaluating the benefits of prostate cancer screening and treatment.
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Affiliation(s)
- Ruihui Gao
- Department of Urology, People's Hospital, Dongxihu District, Wuhan, Hubei 430040, China
| | - Jiayuan Liu
- Department of Urology, People's Hospital, Dongxihu District, Wuhan, Hubei 430040, China
| | - Hengcheng Zhu
- Department of Urology, Wuhan University People's Hospital, Wuhan, Hubei 430060, China
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Ding J, Duan Y, Wang M, Yuan Y, Zhuo Z, Gan L, Song Q, Gao B, Yang L, Liu H, Hou Y, Zheng F, Chen R, Wang J, Lin L, Zhang B, Zhang G, Liu Y. Acceleration of Brain Susceptibility-Weighted Imaging with Compressed Sensitivity Encoding: A Prospective Multicenter Study. AJNR Am J Neuroradiol 2022; 43:402-409. [PMID: 35241421 PMCID: PMC8910792 DOI: 10.3174/ajnr.a7441] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2021] [Accepted: 10/17/2021] [Indexed: 11/07/2022]
Abstract
BACKGROUND AND PURPOSE While three-dimensional susceptibility-weighted imaging has been widely suggested for intracranial vessel imaging, hemorrhage detection, and other neuro-diseases, its relatively long scan time has necessitated the clinical verification of recent progresses of fast imaging techniques. Our aim was to evaluate the effectiveness of brain SWI accelerated by compressed sensitivity encoding to identify the optimal acceleration factors for clinical practice. MATERIALS AND METHODS Ninety-nine subjects, prospectively enrolled from 5 centers, underwent 8 brain SWI sequences: 5 different folds of compressed sensitivity encoding acceleration (CS2, CS4, CS6, CS8, and CS10), 2 different folds of sensitivity encoding acceleration (SF2 and SF4), and 1 without acceleration. Images were assessed quantitatively on both the SNR of the red nucleus and its contrast ratio to the CSF and, subjectively, with scoring on overall image quality; visibility of the substantia nigra-red nucleus, basilar artery, and internal cerebral vein; and diagnostic confidence of the cerebral microbleeds and other intracranial diseases. RESULTS Compressed sensitivity encoding showed a promising ability to reduce the acquisition time (from 202 to 41 seconds) of SWI while increasing the acceleration factor from 2 to 10, though at the cost of decreasing the SNR, contrast ratio, and the scores of visual assessments. The visibility of the substantia nigra-red nucleus and internal cerebral vein became unacceptable in CS6 to CS10. The basilar artery was well-distinguished, and diseases including cerebral microbleeds, cavernous angiomas, intracranial gliomas, venous malformations, and subacute hemorrhage were well-diagnosed in all compressed sensitivity encoding sequences. CONCLUSIONS Compressed sensitivity encoding factor 4 is recommended in routine practice. Compressed sensitivity encoding factor 10 is potentially a fast surrogate for distinguishing the basilar artery and detecting susceptibility-related abnormalities (eg, cerebral microbleeds, cavernous angiomas, gliomas, and venous malformation) at the sacrifice of visualization of the substantia nigra-red nucleus and internal cerebral vein.
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Affiliation(s)
- J. Ding
- From the Department of Radiology (J.D., Y.D., Z.Z., L.G., F.Z., R.C., Y.L.), Beijing Tiantan Hospital, Capital Medical University, Beijing, China
| | - Y. Duan
- From the Department of Radiology (J.D., Y.D., Z.Z., L.G., F.Z., R.C., Y.L.), Beijing Tiantan Hospital, Capital Medical University, Beijing, China
| | - M. Wang
- Department of Radiology (M.W., B.Z.), The Affiliated Drum Tower Hospital of Nanjing UniversityMedical School, Jiangsu, China
| | - Y. Yuan
- Department of Radiology (Y.Y., G.Z.), Beijing Royal Integrative Medicine Hospital, Beijing, China
| | - Z. Zhuo
- From the Department of Radiology (J.D., Y.D., Z.Z., L.G., F.Z., R.C., Y.L.), Beijing Tiantan Hospital, Capital Medical University, Beijing, China
| | - L. Gan
- From the Department of Radiology (J.D., Y.D., Z.Z., L.G., F.Z., R.C., Y.L.), Beijing Tiantan Hospital, Capital Medical University, Beijing, China
| | - Q. Song
- Department of Radiology (Q.S., B.G.), First Affiliated Hospital of Dalian Medical University, Dalian, China
| | - B. Gao
- Department of Radiology (Q.S., B.G.), First Affiliated Hospital of Dalian Medical University, Dalian, China
| | - L. Yang
- Department of Radiology (L.Y., H.L., Y.H.), Shengjing Hospital of ChinaMedical University, Shenyang, China
| | - H. Liu
- Department of Radiology (L.Y., H.L., Y.H.), Shengjing Hospital of ChinaMedical University, Shenyang, China
| | - Y. Hou
- Department of Radiology (L.Y., H.L., Y.H.), Shengjing Hospital of ChinaMedical University, Shenyang, China
| | - F. Zheng
- From the Department of Radiology (J.D., Y.D., Z.Z., L.G., F.Z., R.C., Y.L.), Beijing Tiantan Hospital, Capital Medical University, Beijing, China
| | - R. Chen
- From the Department of Radiology (J.D., Y.D., Z.Z., L.G., F.Z., R.C., Y.L.), Beijing Tiantan Hospital, Capital Medical University, Beijing, China
| | - J. Wang
- Philips Healthcare (J.W., L.L.), Beijing, China
| | - L. Lin
- Philips Healthcare (J.W., L.L.), Beijing, China
| | - B. Zhang
- Department of Radiology (M.W., B.Z.), The Affiliated Drum Tower Hospital of Nanjing UniversityMedical School, Jiangsu, China
| | - G. Zhang
- Department of Radiology (Y.Y., G.Z.), Beijing Royal Integrative Medicine Hospital, Beijing, China
| | - Y. Liu
- From the Department of Radiology (J.D., Y.D., Z.Z., L.G., F.Z., R.C., Y.L.), Beijing Tiantan Hospital, Capital Medical University, Beijing, China
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Duan C, Xiong Y, Cheng K, Xiao S, Lyu J, Wang C, Bian X, Zhang J, Zhang D, Chen L, Zhou X, Lou X. Accelerating susceptibility-weighted imaging with deep learning by complex-valued convolutional neural network (ComplexNet): validation in clinical brain imaging. Eur Radiol 2022; 32:5679-5687. [PMID: 35182203 DOI: 10.1007/s00330-022-08638-1] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2021] [Revised: 12/15/2021] [Accepted: 01/11/2022] [Indexed: 11/30/2022]
Abstract
OBJECTIVES Susceptibility-weighted imaging (SWI) is crucial for the characterization of intracranial hemorrhage and mineralization, but has the drawback of long acquisition times. We aimed to propose a deep learning model to accelerate SWI, and evaluate the clinical feasibility of this approach. METHODS A complex-valued convolutional neural network (ComplexNet) was developed to reconstruct high-quality SWI from highly accelerated k-space data. ComplexNet can leverage the inherently complex-valued nature of SWI data and learn richer representations by using complex-valued network. SWI data were acquired from 117 participants who underwent clinical brain MRI examination between 2019 and 2021, including patients with tumor, stroke, hemorrhage, traumatic brain injury, etc. Reconstruction quality was evaluated using quantitative image metrics and image quality scores, including overall image quality, signal-to-noise ratio, sharpness, and artifacts. RESULTS The average reconstruction time of ComplexNet was 19 ms per section (1.33 s per participant). ComplexNet achieved significantly improved quantitative image metrics compared to a conventional compressed sensing method and a real-valued network with acceleration rates of 5 and 8 (p < 0.001). Meanwhile, there was no significant difference between fully sampled and ComplexNet approaches in terms of overall image quality and artifacts (p > 0.05) at both acceleration rates. Furthermore, ComplexNet showed comparable diagnostic performance to the fully sampled SWI for visualizing a wide range of pathology, including hemorrhage, cerebral microbleeds, and brain tumor. CONCLUSIONS ComplexNet can effectively accelerate SWI while providing superior performance in terms of overall image quality and visualization of pathology for routine clinical brain imaging. KEY POINTS • The complex-valued convolutional neural network (ComplexNet) allowed fast and high-quality reconstruction of highly accelerated SWI data, with an average reconstruction time of 19 ms per section. • ComplexNet achieved significantly improved quantitative image metrics compared to a conventional compressed sensing method and a real-valued network with acceleration rates of 5 and 8 (p < 0.001). • ComplexNet showed comparable diagnostic performance to the fully sampled SWI for visualizing a wide range of pathology, including hemorrhage, cerebral microbleeds, and brain tumor.
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Affiliation(s)
- Caohui Duan
- Department of Radiology, Chinese PLA General Hospital, Beijing, 100853, People's Republic of China
| | - Yongqin Xiong
- Department of Radiology, Chinese PLA General Hospital, Beijing, 100853, People's Republic of China
| | - Kun Cheng
- Department of Radiology, Chinese PLA General Hospital, Beijing, 100853, People's Republic of China
| | - Sa Xiao
- Department of Neurosurgery, Chinese PLA General Hospital, 28 Fuxing Road, Beijing, 100853, People's Republic of China
| | - Jinhao Lyu
- Department of Radiology, Chinese PLA General Hospital, Beijing, 100853, People's Republic of China
| | - Cheng Wang
- Department of Neurosurgery, Chinese PLA General Hospital, 28 Fuxing Road, Beijing, 100853, People's Republic of China
| | - Xiangbing Bian
- Department of Radiology, Chinese PLA General Hospital, Beijing, 100853, People's Republic of China
| | - Jing Zhang
- Department of Radiology, Chinese PLA General Hospital, Beijing, 100853, People's Republic of China
| | - Dekang Zhang
- Department of Radiology, Chinese PLA General Hospital, Beijing, 100853, People's Republic of China
| | - Ling Chen
- Department of Neurosurgery, Chinese PLA General Hospital, 28 Fuxing Road, Beijing, 100853, People's Republic of China
| | - Xin Zhou
- Key Laboratory of Magnetic Resonance in Biological Systems, State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics, National Center for Magnetic Resonance in Wuhan, Wuhan Institute of Physics and Mathematics, Innovation Academy for Precision Measurement Science and Technology, Chinese Academy of Sciences-Wuhan National Laboratory for Optoelectronics, Wuhan, 430071, People's Republic of China
| | - Xin Lou
- Department of Radiology, Chinese PLA General Hospital, Beijing, 100853, People's Republic of China.
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Jia S, Qiu Z, Zhang L, Wang H, Yang G, Liu X, Liang D, Zheng H. Aliasing-free reduced field-of-view parallel imaging. Magn Reson Med 2021; 87:1574-1582. [PMID: 34752654 DOI: 10.1002/mrm.29046] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2021] [Revised: 09/20/2021] [Accepted: 09/27/2021] [Indexed: 11/12/2022]
Abstract
PURPOSE To reconstruct aliasing-free full field-of-view (FOV) images for reduced FOV (rFOV) parallel imaging (PI) with Cartesian and Wave sampling, which suffers from aliasing artifacts using existing PI methods. THEORY AND METHODS The sensitivity encoding method (SENSE) was extended to the Soft-SENSE models supporting multiple-set coil sensitivity maps (CSM) and point spread functions (PSF) for Cartesian and Wave sampled rFOV PI, respectively. The multiple-set CSM and PSF were created from full FOV CSM and PSF according to the image folding process induced by rFOV sampling. The Soft-SENSE reconstructions could be solved by the same algorithms for the conventional full FOV SENSE reconstruction. RESULTS Soft-SENSE using multiple-set full FOV CSM and PSF successfully reconstruct aliasing-free full FOV image from rFOV PI data with Cartesian and Wave sampling. The proposed rFOV PI enables flexible control of the aliasing and achieves comparable geometry factors as the standard full FOV PI with the same net acceleration factor. Reduced FOV PI improves the computational efficiency of iterative compressed sensing (CS) and PI reconstruction, especially for high-resolution volumetric imaging, thanks to the reduced fast Fourier transform (FFT) size. Moreover, rFOV PI reconstruction provides a potential alternative to the phase oversampling for the FOV aliasing problem. CONCLUSION The proposed Soft-SENSE using full FOV CSM and PSF could reconstruct aliasing-free full FOV image for rFOV PI, and make it a viable solution enabling more flexible PI acceleration and effectively improving the computational efficiency of iterative CSPI reconstruction.
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Affiliation(s)
- Sen Jia
- Paul C. Lauterbur Research Centre for Biomedical Imaging, Shenzhen Institutes of Advanced Technology, Chinese Academy of Sciences, Shenzhen, Guangdong, China
| | - Zhilang Qiu
- Paul C. Lauterbur Research Centre for Biomedical Imaging, Shenzhen Institutes of Advanced Technology, Chinese Academy of Sciences, Shenzhen, Guangdong, China.,Shenzhen College of Advanced Technology, University of Chinese Academy of Sciences, Shenzhen, Guangdong, China
| | - Lei Zhang
- Paul C. Lauterbur Research Centre for Biomedical Imaging, Shenzhen Institutes of Advanced Technology, Chinese Academy of Sciences, Shenzhen, Guangdong, China
| | - Haifeng Wang
- Paul C. Lauterbur Research Centre for Biomedical Imaging, Shenzhen Institutes of Advanced Technology, Chinese Academy of Sciences, Shenzhen, Guangdong, China
| | - Gang Yang
- Jinling Hospital, Medical School of Nanjing University, Nanjing, Jiangsu, China
| | - Xin Liu
- Paul C. Lauterbur Research Centre for Biomedical Imaging, Shenzhen Institutes of Advanced Technology, Chinese Academy of Sciences, Shenzhen, Guangdong, China
| | - Dong Liang
- Paul C. Lauterbur Research Centre for Biomedical Imaging, Shenzhen Institutes of Advanced Technology, Chinese Academy of Sciences, Shenzhen, Guangdong, China.,Research Centre of Medical AI, Shenzhen Institutes of Advanced Technology, Chinese Academy of Sciences, Shenzhen, Guangdong, China
| | - Hairong Zheng
- Paul C. Lauterbur Research Centre for Biomedical Imaging, Shenzhen Institutes of Advanced Technology, Chinese Academy of Sciences, Shenzhen, Guangdong, China
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Sakurama A, Fushimi Y, Nakajima S, Sakata A, Hinoda T, Oshima S, Otani S, Wicaksono KP, Liu W, Maki T, Okada T, Takahashi R, Nakamoto Y. Clinical Application of MPRAGE Wave Controlled Aliasing in Parallel Imaging (Wave-CAIPI): A Comparative Study with MPRAGE GRAPPA. Magn Reson Med Sci 2021; 21:633-647. [PMID: 34602534 PMCID: PMC9618934 DOI: 10.2463/mrms.mp.2021-0065] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/05/2022] Open
Abstract
Purpose: To compare reliability and elucidate clinical application of magnetization-prepared rapid gradient-echo (MPRAGE) with 9-fold acceleration by using wave-controlled aliasing in parallel imaging (Wave-CAIPI 3 × 3) in comparison to conventional MPRAGE accelerated by using generalized autocalibrating partially parallel acquisition (GRAPPA) 2 × 1. Methods: A total of 26 healthy volunteers and 33 patients were included in this study. Subjects were scanned with two MPRAGEs, GRAPPA 2 × 1 and Wave-CAIPI 3 × 3 acquired in 5 min 21 s and 1 min 42 s, respectively, on a 3T MR scanner. Healthy volunteers underwent additional two MPRAGEs (CAIPI 3 × 3 and GRAPPA 3 × 3). The image quality of the four MPRAGEs was visually evaluated with a 5-point scale in healthy volunteers, and the SNR of four MPRAGEs was also calculated by measuring the phantom 10 times with each MPRAGE. Based on the results of the visual evaluation, voxel-based morphometry (VBM) analyses, including subfield analysis, were performed only for GRAPPA 2 × 1 and Wave-CAIPI 3 × 3. Correlation of segmentation results between GRAPPA 2 × 1 and Wave-CAIPI 3 × 3 was assessed. Results: In visual evaluations, scores for MPRAGE GRAPPA 2 × 1 (mean rank: 4.00) were significantly better than those for Wave-CAIPI 3 × 3 (mean rank: 3.00), CAIPI 3 × 3 (mean rank: 1.83), and GRAPPA 3 × 3 (mean rank: 1.17), and scores for Wave-CAIPI 3×3 were significantly better than those for CAIPI 3 × 3 and GRAPPA 3 × 3. Image noise was evident at the center for additional MPRAGE CAIPI 3 × 3 and GRAPPA 3 × 3. The correlation of segmentation results between GRAPPA 2 × 1 and Wave-CAIPI 3 × 3 was higher than 0.85 in all VOIs except globus pallidus. Subfield analysis of hippocampus also showed a high correlation between GRAPPA 2 × 1 and Wave-CAIPI 3 × 3. Conclusion: MPRAGE Wave-CAIPI 3 × 3 shows relatively better contrast, despite of its short scan time of 1 min 42 s. The volumes derived from automated segmentation of MPRAGE Wave-CAIPI are considered to be reliable measures.
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Affiliation(s)
- Azusa Sakurama
- Department of Diagnostic Imaging and Nuclear Medicine, Graduate School of Medicine, Kyoto University
| | - Yasutaka Fushimi
- Department of Diagnostic Imaging and Nuclear Medicine, Graduate School of Medicine, Kyoto University
| | - Satoshi Nakajima
- Department of Diagnostic Imaging and Nuclear Medicine, Graduate School of Medicine, Kyoto University
| | - Akihiko Sakata
- Department of Diagnostic Imaging and Nuclear Medicine, Graduate School of Medicine, Kyoto University
| | - Takuya Hinoda
- Department of Diagnostic Imaging and Nuclear Medicine, Graduate School of Medicine, Kyoto University
| | - Sonoko Oshima
- Department of Diagnostic Imaging and Nuclear Medicine, Graduate School of Medicine, Kyoto University
| | - Sayo Otani
- Department of Diagnostic Imaging and Nuclear Medicine, Graduate School of Medicine, Kyoto University
| | - Krishna Pandu Wicaksono
- Department of Diagnostic Imaging and Nuclear Medicine, Graduate School of Medicine, Kyoto University
| | - Wei Liu
- Siemens Shenzhen Magnetic Resonance Ltd
| | - Takakuni Maki
- Department of Neurology, Graduate School of Medicine, Kyoto University
| | - Tomohisa Okada
- Human Brain Research Center, Graduate School of Medicine, Kyoto University
| | - Ryosuke Takahashi
- Department of Neurology, Graduate School of Medicine, Kyoto University
| | - Yuji Nakamoto
- Department of Diagnostic Imaging and Nuclear Medicine, Graduate School of Medicine, Kyoto University
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Wave-controlled aliasing in parallel imaging magnetization-prepared gradient echo (wave-CAIPI MPRAGE) accelerates speed for pediatric brain MRI with comparable diagnostic performance. Sci Rep 2021; 11:13296. [PMID: 34168260 PMCID: PMC8225910 DOI: 10.1038/s41598-021-92759-y] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2021] [Accepted: 06/11/2021] [Indexed: 01/07/2023] Open
Abstract
We aimed to compare accelerated post-contrast magnetization-prepared rapid gradient-echo (MPRAGE) using wave-controlled aliasing in parallel imaging (wave-CAIPI) with conventional MPRAGE as a reliable method to diagnose intracranial lesions in pediatric patients. A total of 23 consecutive pediatric patients who underwent post-contrast wave-CAIPI and conventional MPRAGE (scan time: 2 min 39 s vs. 5 min 46 s) were retrospectively evaluated. Two radiologists independently assessed each image for the presence of intracranial lesions. Quantitative [contrast-to-noise ratio (CNR), contrast rate (CR), and signal-to-noise ratio (SNR)] and qualitative parameters (overall image quality, gray-white matter differentiation, demarcation of basal ganglia and sulci, and motion artifacts) were also surveyed. Wave-CAIPI MPRAGE and conventional MPRAGE detected enhancing and non-enhancing intracranial lesions with 100% agreement. Although wave-CAIPI MPRAGE had a lower SNR (all p < 0.05) and overall image quality (overall analysis, p = 0.02) compared to conventional MPRAGE, other quantitative (CNR and CR) and qualitative parameters (gray-white differentiation, demarcation of basal ganglia and sulci, and motion artifacts) were comparable in the pooled analysis and between both observers (all p > 0.05). Wave-CAIPI MPRAGE was a reliable method for diagnosing intracranial lesions in pediatric patients as conventional MPRAGE at half the scan time.
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12
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Goncalves Filho ALM, Longo MGF, Conklin J, Cauley SF, Polak D, Liu W, Splitthoff DN, Lo WC, Kirsch JE, Setsompop K, Schaefer PW, Huang SY, Rapalino O. MRI Highly Accelerated Wave-CAIPI T1-SPACE versus Standard T1-SPACE to detect brain gadolinium-enhancing lesions at 3T. J Neuroimaging 2021; 31:893-901. [PMID: 34081374 DOI: 10.1111/jon.12893] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2021] [Revised: 05/10/2021] [Accepted: 05/21/2021] [Indexed: 11/28/2022] Open
Abstract
BACKGROUND AND PURPOSE High-resolution three-dimensional (3D) post-contrast imaging of the brain is essential for comprehensive evaluation of inflammatory, neoplastic, and neurovascular diseases of the brain. 3D T1-weighted spin-echo-based sequences offer increased sensitivity for the detection of enhancing lesions but are relatively prolonged examinations. We evaluated whether a highly accelerated Wave-controlled aliasing in parallel imaging (Wave-CAIPI) post-contrast 3D T1-sampling perfection with application-optimized contrasts using different flip angle evolutions (T1-SPACE) sequence (Wave-T1-SPACE) was noninferior to the standard high-resolution 3D T1-SPACE sequence for visualizing enhancing lesions with comparable diagnostic quality. METHODS One hundred and three consecutive patients were prospectively evaluated with a standard post-contrast 3D T1-SPACE sequence (acquisition time [TA] = 4 min 19 s) and an optimized Wave-CAIPI 3D T1-SPACE sequence (TA = 1 min 40 s) that was nearly three times faster than the standard sequence. Two blinded neuroradiologists performed a head-to-head comparison to evaluate the visualization of enhancing pathology, perception of artifacts, and overall diagnostic quality. A 15% margin was used to test whether post-contrast Wave-T1-SPACE was noninferior to standard T1-SPACE. RESULTS Wave-T1-SPACE was noninferior to standard T1-SPACE for delineating parenchymal and meningeal enhancing pathology (p < 0.01). Wave-T1-SPACE showed marginally higher background noise compared to the standard sequence and was noninferior in the overall diagnostic quality (p = 0.03). CONCLUSIONS Our findings show that Wave-T1-SPACE was noninferior to standard T1-SPACE for visualization of enhancing pathology and overall diagnostic quality with a three-fold reduction in acquisition time compared to the standard sequence. Wave-T1-SPACE may be used to accelerate 3D post-contrast T1-weighted spin-echo imaging without loss of clinically important information.
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Affiliation(s)
- Augusto Lio M Goncalves Filho
- Department of Radiology, Massachusetts General Hospital, Harvard Medical School, Boston, Massachusetts, USA.,Athinoula A. Martinos Center for Biomedical Imaging, Charlestown, Massachusetts, USA
| | - M Gabriela Figueiro Longo
- Department of Radiology, Massachusetts General Hospital, Harvard Medical School, Boston, Massachusetts, USA
| | - John Conklin
- Department of Radiology, Massachusetts General Hospital, Harvard Medical School, Boston, Massachusetts, USA
| | - Stephen F Cauley
- Department of Radiology, Massachusetts General Hospital, Harvard Medical School, Boston, Massachusetts, USA.,Athinoula A. Martinos Center for Biomedical Imaging, Charlestown, Massachusetts, USA
| | | | - Wei Liu
- Siemens Shenzhen Magnetic Resonance Ltd., Shenzhen, China
| | | | - Wei-Ching Lo
- Siemens Medical Solutions, Boston, Massachusetts, USA
| | - John E Kirsch
- Department of Radiology, Massachusetts General Hospital, Harvard Medical School, Boston, Massachusetts, USA
| | - Kawin Setsompop
- Department of Radiology, Massachusetts General Hospital, Harvard Medical School, Boston, Massachusetts, USA.,Athinoula A. Martinos Center for Biomedical Imaging, Charlestown, Massachusetts, USA
| | - Pamela W Schaefer
- Department of Radiology, Massachusetts General Hospital, Harvard Medical School, Boston, Massachusetts, USA
| | - Susie Y Huang
- Department of Radiology, Massachusetts General Hospital, Harvard Medical School, Boston, Massachusetts, USA.,Athinoula A. Martinos Center for Biomedical Imaging, Charlestown, Massachusetts, USA
| | - Otto Rapalino
- Department of Radiology, Massachusetts General Hospital, Harvard Medical School, Boston, Massachusetts, USA
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13
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Wu M, Wang C, Lin P, Chao T. Technical Note: Optimization of quantitative susceptibility mapping by streaking artifact detection. Med Phys 2020; 47:5715-5722. [DOI: 10.1002/mp.14460] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2019] [Revised: 07/22/2020] [Accepted: 07/22/2020] [Indexed: 11/10/2022] Open
Affiliation(s)
- Ming‐Long Wu
- Department of Computer Science and Information Engineering National Cheng Kung University No. 1, University Road Tainan 70101 Taiwan
- Institute of Medical Informatics National Cheng Kung University No. 1, University Road Tainan 70101 Taiwan
| | - Chun‐Kun Wang
- Institute of Medical Informatics National Cheng Kung University No. 1, University Road Tainan 70101 Taiwan
| | - Po‐Yu Lin
- Department of Computer Science and Information Engineering National Cheng Kung University No. 1, University Road Tainan 70101 Taiwan
| | - Tzu‐Cheng Chao
- Department of Radiology Mayo Clinic 200 First St. SW Rochester MN 55905 USA
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14
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Goncalves Filho ALM, Conklin J, Longo MGF, Cauley SF, Polak D, Liu W, Splitthoff DN, Lo WC, Kirsch JE, Setsompop K, Schaefer PW, Huang SY, Rapalino O. Accelerated Post-contrast Wave-CAIPI T1 SPACE Achieves Equivalent Diagnostic Performance Compared With Standard T1 SPACE for the Detection of Brain Metastases in Clinical 3T MRI. Front Neurol 2020; 11:587327. [PMID: 33193054 PMCID: PMC7653188 DOI: 10.3389/fneur.2020.587327] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2020] [Accepted: 09/30/2020] [Indexed: 12/12/2022] Open
Abstract
Background and Purpose: Brain magnetic resonance imaging (MRI) examinations using high-resolution 3D post-contrast sequences offer increased sensitivity for the detection of metastases in the central nervous system but are usually long exams. We evaluated whether the diagnostic performance of a highly accelerated Wave-controlled aliasing in parallel imaging (Wave-CAIPI) post-contrast 3D T1 SPACE sequence was non-inferior to the standard high-resolution 3D T1 SPACE sequence for the evaluation of brain metastases. Materials and Methods: Thirty-three patients undergoing evaluation for brain metastases were prospectively evaluated with a standard post-contrast 3D T1 SPACE sequence and an optimized Wave-CAIPI 3D T1 SPACE sequence, which was three times faster than the standard sequence. Two blinded neuroradiologists performed a head-to-head comparison to evaluate the visualization of pathology, perception of artifacts, and the overall diagnostic quality. Wave-CAIPI post-contrast T1 SPACE was tested for non-inferiority relative to standard T1 SPACE using a 15% non-inferiority margin. Results: Wave-CAIPI post-contrast T1 SPACE was non-inferior to the standard T1 SPACE for visualization of enhancing lesions (P < 0.01) and offered equivalent diagnostic quality performance and only marginally higher background noise compared to the standard sequence. Conclusions: Our findings suggest that Wave-CAIPI post-contrast T1 SPACE provides equivalent visualization of pathology and overall diagnostic quality with three times reduced scan time compared to the standard 3D T1 SPACE.
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Affiliation(s)
- Augusto Lio M Goncalves Filho
- Department of Radiology, Massachusetts General Hospital, Boston, MA, United States.,Athinoula A. Martinos Center for Biomedical Imaging, Charlestown, MA, United States.,Harvard Medical School, Boston, MA, United States
| | - John Conklin
- Department of Radiology, Massachusetts General Hospital, Boston, MA, United States.,Athinoula A. Martinos Center for Biomedical Imaging, Charlestown, MA, United States.,Harvard Medical School, Boston, MA, United States
| | - Maria Gabriela F Longo
- Department of Radiology, Massachusetts General Hospital, Boston, MA, United States.,Athinoula A. Martinos Center for Biomedical Imaging, Charlestown, MA, United States.,Harvard Medical School, Boston, MA, United States
| | - Stephen F Cauley
- Department of Radiology, Massachusetts General Hospital, Boston, MA, United States.,Athinoula A. Martinos Center for Biomedical Imaging, Charlestown, MA, United States.,Harvard Medical School, Boston, MA, United States
| | - Daniel Polak
- Athinoula A. Martinos Center for Biomedical Imaging, Charlestown, MA, United States.,Siemens Healthcare GmbH, Erlangen, Germany
| | - Wei Liu
- Siemens Shenzhen Magnetic Resonance Ltd., Shenzhen, China
| | | | - Wei-Ching Lo
- Siemens Medical Solutions, Boston, MA, United States
| | - John E Kirsch
- Department of Radiology, Massachusetts General Hospital, Boston, MA, United States.,Athinoula A. Martinos Center for Biomedical Imaging, Charlestown, MA, United States.,Harvard Medical School, Boston, MA, United States
| | - Kawin Setsompop
- Department of Radiology, Massachusetts General Hospital, Boston, MA, United States.,Athinoula A. Martinos Center for Biomedical Imaging, Charlestown, MA, United States.,Harvard Medical School, Boston, MA, United States.,Harvard-MIT Division of Health Sciences and Technology, Cambridge, MA, United States
| | - Pamela W Schaefer
- Department of Radiology, Massachusetts General Hospital, Boston, MA, United States.,Harvard Medical School, Boston, MA, United States
| | - Susie Y Huang
- Department of Radiology, Massachusetts General Hospital, Boston, MA, United States.,Athinoula A. Martinos Center for Biomedical Imaging, Charlestown, MA, United States.,Harvard Medical School, Boston, MA, United States.,Harvard-MIT Division of Health Sciences and Technology, Cambridge, MA, United States
| | - Otto Rapalino
- Department of Radiology, Massachusetts General Hospital, Boston, MA, United States.,Harvard Medical School, Boston, MA, United States
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