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Wang X, Cao YY, Jiang Y, Jia M, Tian G, Bu CQ, Zhao N, Yue XZ, Shen ZW, Ji Y, Han YD. Effects of Breathing Patterns on Amide Proton Transfer MRI in the Kidney: A Preliminary Comparative Study in Healthy Volunteers and Patients With Tumors. J Magn Reson Imaging 2024; 60:222-230. [PMID: 37888865 DOI: 10.1002/jmri.29099] [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: 08/01/2023] [Revised: 10/16/2023] [Accepted: 10/16/2023] [Indexed: 10/28/2023] Open
Abstract
BACKGROUND The amide proton transfer-weighted (APTw) imaging for kidney diseases is important. However, the breathing patterns on APTw imaging remains unexplored. PURPOSE This study aimed to investigate the effects of intermittent breath-hold (IBH) and free breathing (FB) on renal 3D-APTw imaging. STUDY TYPE Healthy volunteers were enrolled prospectively, and renal clear cell carcinoma (RCCC) patients were included retrospectively. POPULATION 58 healthy volunteers and 10 RCCC patients. FIELD STRENGTH/SEQUENCE 3-T, turbo spin echo, and fast field echo. ASSESSMENT 3D-APTw imaging was scanned using the IBH and FB methods in volunteers and using the IBH method in RCCC patients. The image quality was evaluated by three observers according to the 5-point Likert scale. Optimal images rated at three points or higher were used to measure the APT values. STATISTICAL ANALYSIS The measurement repeatability was assessed using the intraclass correlation coefficient (ICC) and the Bland-Altman plot. The APT values were analyzed using McNemar's test, one-way analysis of variance, and t test. RESULTS 50 healthy volunteers and 8 RCCC patients were enrolled. Renal 3D-APTw imaging using the IBH method revealed a higher success rate (88% vs 78%). The ICCs were excellent in the IBH group (ICCs > 0.74) and were good in the FB group (ICCs < 0.74). No significant differences in the APT values among various zones using the IBH (P = 0.263) or FB method (P = 0.506). The mean APT value using the IBH method (2.091% ± 0.388%) was slightly lower than the FB method (2.176% ± 0.292%), but no significant difference (P = 0.233). The APT value of RCCC (4.832% ± 1.361%) was considerably higher than normal renal using the IBH method. CONCLUSIONS The study demonstrated that the IBH method substantially increased the image quality of renal 3D-APTw imaging. Furthermore, APT values may vary between normal and tumor tissues. LEVEL OF EVIDENCE 2 TECHNICAL EFFICACY: Stage 2.
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Affiliation(s)
- X Wang
- Department of Radiology, Xi'an GaoXin Hospital, Xi'an Jiao Tong University, Xi'an, Shaanxi, China
| | - Y Y Cao
- Department of Imaging Center, First Affiliated Hospital, Xi'an Medical University, Xi'an, Shaanxi, China
| | - Y Jiang
- Department of Radiology, Xi'an GaoXin Hospital, Xi'an Jiao Tong University, Xi'an, Shaanxi, China
| | - M Jia
- Department of Radiology, Xi'an GaoXin Hospital, Xi'an Jiao Tong University, Xi'an, Shaanxi, China
| | - G Tian
- Department of Radiology, Xi'an GaoXin Hospital, Xi'an Jiao Tong University, Xi'an, Shaanxi, China
| | - C Q Bu
- Department of Radiology, Xi'an GaoXin Hospital, Xi'an Jiao Tong University, Xi'an, Shaanxi, China
| | - N Zhao
- Department of Radiology, Xi'an GaoXin Hospital, Xi'an Jiao Tong University, Xi'an, Shaanxi, China
| | - X Z Yue
- Philips Healthcare, Beijing, China
| | - Z W Shen
- Philips Healthcare, Beijing, China
| | - Y Ji
- Department of Imaging Center, First Affiliated Hospital, Xi'an Medical University, Xi'an, Shaanxi, China
| | - Y D Han
- Department of Radiology, Xi'an GaoXin Hospital, Xi'an Jiao Tong University, Xi'an, Shaanxi, China
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Alfaleh H, Melkus G, Nasiyabi KA, McInnes MDF, Schieda N. Comparison of image quality and depiction of microscopic fat at 2-D and 3-D T1-Weighted (T1W) chemical shift (dual-echo) MRI for evaluation of adrenal adenomas. ABDOMINAL RADIOLOGY (NEW YORK) 2022; 47:3828-3837. [PMID: 36008733 DOI: 10.1007/s00261-022-03648-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/09/2022] [Revised: 08/04/2022] [Accepted: 08/08/2022] [Indexed: 01/18/2023]
Abstract
OBJECTIVE To compare image quality and detection of microscopic fat in adrenal adenomas imaged with 2-D and 3-D chemical shift imaging (CSI) and, to derive parameters which best match 2-D and 3-D-CSI. METHODS This two-phase, retrospective, and phantom + prospective study was IRB approved. First, a retrospective assessment of 50 consecutive adrenal adenomas imaged at 1.5 T with 2-D (TR minimum, Flip Angle [FA] 70°, TE 2.2/4.4 ms.) and 3-D (TR minimum, FA 10°, TE 2.2/4.4 ms.] CSI was performed. Second, phantom (varied fat: water concentration) experiments guided a prospective assessment of 12 consecutive adrenal adenomas imaged at 1.5 T with 3-D CSI (FA 10°, 18°). Two blinded radiologists independently evaluated: image quality, signal intensity (SI) cancellation (5-point Likert scale), and CSI-index ([SI.In.Phase-SI.Opposed.Phase/SI.In.Phase]*100). RESULTS 2-D-CSI yielded higher image quality (p < 0.001) and, subjectively (p < 0.001) and quantitatively (p < 0.001) had more SI cancellation from microscopic fat. Proportion of adenomas with no detectable microscopic fat (3-D; 26-36% subjectively, 18-24% quantitatively [CSI-index < 16.5%] versus 2-D; 20-22% subjectively, 6-8% quantitatively) differed (p = 0.008-0.08 subjectively, 0.008-0.03 quantitatively) by CSI technique. Phantom experiments indicated 18°FA 3-D-CSI compared favorably to 70° 2-D-CSI for fat detection between 5% and 50%. In vivo, there was no differences in subjective or quantitative SI cancellation comparing 18°3D-CSI and 2D-CSI (p = 0.16-0.56 and 0.73-0.60). Greater SI cancellation occurred with 18°3D compared to 10°3D-CSI evaluated subjectively (p = 0.003-0.01). CONCLUSION 2-D CSI has subjectively higher image quality and shows more signal intensity loss from microscopic fat in adrenal adenomas compared to 10° flip angle 3-D-CSI. Increasing the 3-D flip angle to 18° more closely matches depiction of microscopic fat to 2-D-CSI at 1.5 T.
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Affiliation(s)
- Hana Alfaleh
- Department of Medical Imaging, The Ottawa Hospital, 1053 Carling Avenue, Room C159, Ottawa, ON, K1Y 4E9, Canada
| | - Gerd Melkus
- The Ottawa Hospital Research Institute, The Ottawa Hospital Research Institute, Ottawa, ON, Canada
| | - Khalid Alo Nasiyabi
- Department of Medical Imaging, The Ottawa Hospital, 1053 Carling Avenue, Room C159, Ottawa, ON, K1Y 4E9, Canada
| | - Matthew D F McInnes
- Department of Medical Imaging, The Ottawa Hospital, 1053 Carling Avenue, Room C159, Ottawa, ON, K1Y 4E9, Canada
| | - Nicola Schieda
- Department of Medical Imaging, The Ottawa Hospital, 1053 Carling Avenue, Room C159, Ottawa, ON, K1Y 4E9, Canada.
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Direct Comparison of Diagnostic Accuracy of Fast Kilovoltage Switching Dual-Energy Computed Tomography and Magnetic Resonance Imaging for Detection of Enhancement in Renal Masses. J Comput Assist Tomogr 2022; 46:862-870. [DOI: 10.1097/rct.0000000000001361] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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Edney E, Davenport MS, Curci N, Schieda N, Krishna S, Hindman N, Silverman SG, Pedrosa I. Bosniak classification of cystic renal masses, version 2019: interpretation pitfalls and recommendations to avoid misclassification. Abdom Radiol (NY) 2021; 46:2699-2711. [PMID: 33484283 DOI: 10.1007/s00261-020-02906-8] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2020] [Revised: 12/01/2020] [Accepted: 12/06/2020] [Indexed: 12/22/2022]
Abstract
The purpose of this review is to describe the potential sources of variability or discrepancy in interpretation of cystic renal masses under the Bosniak v2019 classification system. Strategies to avoid these pitfalls and clinical examples of diagnostic approaches are also presented. Potential pitfalls in the application of Bosniak v2019 are divided into three categories: interpretative, technical, and mass related. An organized, comprehensive review of possible discrepancies in interpreting Bosniak v2019 cystic masses is presented with pictorial examples of difficult clinical cases and proposed solutions. The scheme provided can guide readers to consistent, precise application of the classification system. Radiologists should be aware of the possible sources of misinterpretation of cystic renal masses when applying Bosniak v2019. Knowing which features and types of cystic masses are prone to interpretive errors, in addition to the inherent trade-offs between the CT and MR techniques used to characterize them, can help radiologists avoid these pitfalls.
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Affiliation(s)
- Elizabeth Edney
- Department of Radiology, University of Nebraska Medical Center, Omaha, NE, USA.
| | - Matthew S Davenport
- Departments of Radiology and Urology, Michigan Medicine, University of Michigan, Ann Arbor, MI, USA
| | - Nicole Curci
- Department of Radiology, Michigan Medicine, University of Michigan, Ann Arbor, MI, USA
| | - Nicola Schieda
- Department of Medical Imaging, The Ottawa Hospital, University of Ottawa, Ottawa, ON, Canada
| | - Satheesh Krishna
- Joint Department of Medical Imaging, University Health Network, Mount Sinai Hospital and Women's College Hospital, University of Toronto, Toronto, ON, Canada
| | - Nicole Hindman
- Department of Radiology, New York University Langone Medical Center, New York, USA
| | - Stuart G Silverman
- Department of Radiology, Brigham and Women's Hospital, Harvard Medical School, Boston, MA, USA
| | - Ivan Pedrosa
- Department of Radiology, University of Texas Southwestern Medical Center, Dallas, TX, USA
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Li H, Meng X, Guan X, Zhou N, Liu H, Zhang Y, Yu B, Zhu H, Li N, Yang Z. Clinical Evaluation of MR-Gated Respiratory Motion Correction in Simultaneous PET/MRI. Clin Nucl Med 2021; 46:297-302. [PMID: 33512946 DOI: 10.1097/rlu.0000000000003510] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
Abstract
PURPOSE The recently available gated T1-weighted imaging with the Dixon technique enables the synchronized gating signal for both MR acquisition and PET reconstruction. Herein, we evaluated the clinical value of this MR-gated PET reconstruction in the thoracic-abdominal PET/MRI compared with non-MR-gated method. METHODS Twenty patients (28 hypermetabolic target lesions) underwent PET/MRI. Four types of PET images were reconstructed: non-MR-gating + gated attenuation correction (AC) (group A), MR-gating + gated AC (group B), non-MR-gating + breath-hold (BH) AC (group C), and MR-gating + BH AC (group D). A 4-point objective scale (from well match to obvious mismatch was scored from 3 to 0) was proposed to evaluate the mismatch. The detection rate and quantitative metrics were also evaluated. RESULTS In the patient-based analysis, for groups A through D, the detection rates were 90%, 100%, 85%, and 90% as well as 95%, 100%, 85%, and 85%, assessed by readers 1 and 2, respectively, and significant difference of mismatch score was observed with the highest proportion of 3 points in group B (85%, 90%, 35%, and 40%, and 80%, 90%, 35%, and 20%, assessed by readers 1 and 2, respectively). The lesion-based analysis demonstrated significant differences in quantitative metrics for groups A through D (all P's < 0.05), with the highest quantitative metrics in group B (SUVmax: 7.49 ± 3.37, 8.45 ± 3.82, 6.90 ± 3.24, and 7.69 ± 3.50; SUVmean: 3.90 ± 1.60, 4.34 ± 1.84, 3.67 ± 1.61, and 4.03 ± 1.81; SUVpeak: 5.60 ± 2.50, 6.10 ± 2.80, 5.22 ± 2.40, and 5.65 ± 2.68; signal-to-noise ratio: 136.06 ± 90.58, 136.24 ± 81.63, 99.52 ± 53.16, and 107.57 ± 69.05). CONCLUSIONS The MR-gated reconstruction using gated AC reduced the mismatch between MR and PET images and improved the thoracic-abdominal PET image quality in simultaneous PET/MRI systems.
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Affiliation(s)
- Hui Li
- From the Key Laboratory of Carcinogenesis and Translational Research (Ministry of Education/Beijing), Department of Nuclear Medicine, Peking University Cancer Hospital and Institute, Beijing
| | - Xiangxi Meng
- From the Key Laboratory of Carcinogenesis and Translational Research (Ministry of Education/Beijing), Department of Nuclear Medicine, Peking University Cancer Hospital and Institute, Beijing
| | - Xiangping Guan
- From the Key Laboratory of Carcinogenesis and Translational Research (Ministry of Education/Beijing), Department of Nuclear Medicine, Peking University Cancer Hospital and Institute, Beijing
| | - Nina Zhou
- From the Key Laboratory of Carcinogenesis and Translational Research (Ministry of Education/Beijing), Department of Nuclear Medicine, Peking University Cancer Hospital and Institute, Beijing
| | - Hui Liu
- United Imaging Healthcare, Shanghai, China
| | - Yan Zhang
- From the Key Laboratory of Carcinogenesis and Translational Research (Ministry of Education/Beijing), Department of Nuclear Medicine, Peking University Cancer Hospital and Institute, Beijing
| | - Boqi Yu
- From the Key Laboratory of Carcinogenesis and Translational Research (Ministry of Education/Beijing), Department of Nuclear Medicine, Peking University Cancer Hospital and Institute, Beijing
| | - Hua Zhu
- From the Key Laboratory of Carcinogenesis and Translational Research (Ministry of Education/Beijing), Department of Nuclear Medicine, Peking University Cancer Hospital and Institute, Beijing
| | - Nan Li
- From the Key Laboratory of Carcinogenesis and Translational Research (Ministry of Education/Beijing), Department of Nuclear Medicine, Peking University Cancer Hospital and Institute, Beijing
| | - Zhi Yang
- From the Key Laboratory of Carcinogenesis and Translational Research (Ministry of Education/Beijing), Department of Nuclear Medicine, Peking University Cancer Hospital and Institute, Beijing
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Krishna S, Schieda N, Pedrosa I, Hindman N, Baroni RH, Silverman SG, Davenport MS. Update on MRI of Cystic Renal Masses Including Bosniak Version 2019. J Magn Reson Imaging 2020; 54:341-356. [PMID: 33009722 DOI: 10.1002/jmri.27364] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2020] [Revised: 08/27/2020] [Accepted: 08/28/2020] [Indexed: 12/15/2022] Open
Abstract
Incidental cystic renal masses are common, usually benign, and almost always indolent. Since 1986, the Bosniak classification has been used to express the risk of malignancy in a cystic renal mass detected at imaging. Historically, magnetic resonance imaging (MRI) was not included in that classification. The proposed Bosniak v.2019 update has formally incorporated MRI, included definitions of imaging terms designed to improve interobserver agreement and specificity for malignancy, and incorporated a variety of masses that were incompletely defined or not included in the original classification. For example, at unenhanced MRI, homogeneous masses markedly hyperintense at T2 -weighted imaging (similar to cerebrospinal fluid) and homogeneous masses markedly hyperintense at fat suppressed T1 -weighted imaging (approximately ≥2.5 times more intense than adjacent renal parenchyma) are classified as Bosniak II and may be safely ignored, even when they have not been imaged with a complete renal mass MRI protocol. MRI has specific advantages and is recommended to evaluate masses that at computed tomography (CT) 1) have abundant thick or nodular calcifications; 2) are homogeneous, hyperattenuating, ≥3 cm, and nonenhancing; or 3) are heterogeneous and nonenhancing. Although MRI is generally excellent for characterizing cystic renal masses, there are unique weaknesses of MRI that bear consideration. These details and others related to MRI of cystic renal masses are described in this review, with an emphasis on Bosniak v.2019. A website (https://bosniak-calculator.herokuapp.com/) and mobile phone apps named "Bosniak Calculator" have been developed for ease of assignment of Bosniak classes. LEVEL OF EVIDENCE: 5 TECHNICAL EFFICACY STAGE: 3.
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Affiliation(s)
- Satheesh Krishna
- Joint Department of Medical Imaging, University Health Network, Mount Sinai Hospital and Women's College Hospital, University of Toronto, Toronto, Ontario, Canada
| | - Nicola Schieda
- Department of Medical Imaging, The Ottawa Hospital, University of Ottawa, Ottawa, Ontario, Canada
| | - Ivan Pedrosa
- Department of Radiology, University of Texas Southwestern Medical Center, Dallas, Texas, USA
| | - Nicole Hindman
- Department of Radiology, New York University Langone Medical Center, New York, New York, USA
| | - Ronaldo H Baroni
- Department of Radiology and Diagnostic Imaging, Hospital Israelita Albert Einstein, São Paulo, Brazil
| | - Stuart G Silverman
- Department of Radiology, Brigham and Women's Hospital, Harvard Medical School, Boston, Massachusetts, USA
| | - Matthew S Davenport
- Departments of Radiology and Urology, Michigan Medicine, University of Michigan, Ann Arbor, Michigan, USA
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Primary and secondary diseases of the perinephric space: an approach to imaging diagnosis with emphasis on MRI. Clin Radiol 2020; 76:75.e13-75.e26. [PMID: 32709392 DOI: 10.1016/j.crad.2020.06.022] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2020] [Accepted: 06/17/2020] [Indexed: 12/21/2022]
Abstract
The perinephric space is the middle compartment of the retroperitoneum, containing the kidneys and adrenal glands. Differential considerations for diseases involving primarily the perinephric space differ from those arising from the kidney itself, show variant imaging features, and require identification and characterisation by interpreting radiologists-an imaging diagnosis can be suggested in many cases. Lymphangiomas are congenital cystic lesions that may contain lipid-laden chyle, which may be detectable on magnetic resonance imaging (MRI). Retroperitoneal fibrosis, Erdheim-Chester disease, and lymphoma may present as a perinephric soft tissue rind. Osseous findings favour Erdheim-Chester, ureteric obstruction favours retroperitoneal fibrosis, and associated lymphadenopathy with mass-effect, but without invasion of adjacent structures favours lymphoma. Extramedullary haematopoiesis and brown fat stimulation are both characterised by signal drop on opposed-phase T1-weighted (W) images, the former resulting from severe anaemia and the latter in the context of elevated serum catecholamines, especially in the setting of phaeochromocytoma. Liposarcoma is the most common primary sarcoma of the retroperitoneum. Metastases are uncommon; however, they can be seen in melanoma, among other primary malignancies. Increased T1W signal hyperintensity is typical of melanoma metastases and haematomas. Abscesses show non-enhancing fluid centrally with marked diffusion restriction. This article presents a review of the perinephric space, pathological conditions of the perinephric space, and an approach towards imaging and diagnosis using cross-sectional imaging, with emphasis on MRI. MRI provides better tissue characterisation, assessment of enhancement kinetics, and detection of intralesional fat in comparison to CT. Clinical and laboratory correlation or tissue sampling may be required for definitive diagnosis in some cases.
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Uthoff J, Larson J, Sato TS, Hammond E, Schroeder KE, Rohret F, Rogers CS, Quelle DE, Darbro BW, Khanna R, Weimer JM, Meyerholz DK, Sieren JC. Longitudinal phenotype development in a minipig model of neurofibromatosis type 1. Sci Rep 2020; 10:5046. [PMID: 32193437 PMCID: PMC7081358 DOI: 10.1038/s41598-020-61251-4] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2019] [Accepted: 02/17/2020] [Indexed: 12/24/2022] Open
Abstract
Neurofibromatosis type 1 (NF1) is a rare, autosomal dominant disease with variable clinical presentations. Large animal models are useful to help dissect molecular mechanisms, determine relevant biomarkers, and develop effective therapeutics. Here, we studied a NF1 minipig model (NF1+/ex42del) for the first 12 months of life to evaluate phenotype development, track disease progression, and provide a comparison to human subjects. Through systematic evaluation, we have shown that compared to littermate controls, the NF1 model develops phenotypic characteristics of human NF1: [1] café-au-lait macules, [2] axillary/inguinal freckling, [3] shortened stature, [4] tibial bone curvature, and [5] neurofibroma. At 4 months, full body computed tomography imaging detected significantly smaller long bones in NF1+/ex42del minipigs compared to controls, indicative of shorter stature. We found quantitative evidence of tibial bowing in a subpopulation of NF1 minipigs. By 8 months, an NF1+/ex42del boar developed a large diffuse shoulder neurofibroma, visualized on magnetic resonance imaging, which subsequently grew in size and depth as the animal aged up to 20 months. The NF1+/ex42del minipig model progressively demonstrates signature attributes that parallel clinical manifestations seen in humans and provides a viable tool for future translational NF1 research.
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Affiliation(s)
- Johanna Uthoff
- Department of Radiology, University of Iowa, Iowa City, IA, USA
- Department of Biomedical Engineering, University of Iowa, Iowa City, IA, USA
- Holden Comprehensive Cancer Center, University of Iowa, Iowa City, IA, USA
| | - Jared Larson
- Department of Radiology, University of Iowa, Iowa City, IA, USA
| | - Takashi S Sato
- Department of Radiology, University of Iowa, Iowa City, IA, USA
| | - Emily Hammond
- Department of Radiology, University of Iowa, Iowa City, IA, USA
- Department of Biomedical Engineering, University of Iowa, Iowa City, IA, USA
- Holden Comprehensive Cancer Center, University of Iowa, Iowa City, IA, USA
| | | | | | | | - Dawn E Quelle
- Holden Comprehensive Cancer Center, University of Iowa, Iowa City, IA, USA
- Department of Pharmacology, University of Iowa, Iowa City, IA, USA
| | - Benjamin W Darbro
- Holden Comprehensive Cancer Center, University of Iowa, Iowa City, IA, USA
- Department of Pediatrics, University of Iowa, Iowa City, IA, USA
| | - Rajesh Khanna
- Department of Pharmacology, University of Arizona, Tucson, AZ, USA
| | - Jill M Weimer
- Pediatrics and Rare Diseases Group, Sanford Research, Sioux Falls, SD, USA
| | | | - Jessica C Sieren
- Department of Radiology, University of Iowa, Iowa City, IA, USA.
- Department of Biomedical Engineering, University of Iowa, Iowa City, IA, USA.
- Holden Comprehensive Cancer Center, University of Iowa, Iowa City, IA, USA.
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