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Svoboda E, Bořil T, Rusz J, Tykalová T, Horáková D, Guttmann CRG, Blagoev KB, Hatabu H, Valtchinov VI. Assessing clinical utility of machine learning and artificial intelligence approaches to analyze speech recordings in multiple sclerosis: A pilot study. Comput Biol Med 2022; 148:105853. [PMID: 35870318 DOI: 10.1016/j.compbiomed.2022.105853] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2021] [Revised: 04/09/2022] [Accepted: 05/23/2022] [Indexed: 11/26/2022]
Abstract
BACKGROUND An early diagnosis together with an accurate disease progression monitoring of multiple sclerosis is an important component of successful disease management. Prior studies have established that multiple sclerosis is correlated with speech discrepancies. Early research using objective acoustic measurements has discovered measurable dysarthria. METHOD The objective was to determine the potential clinical utility of machine learning and deep learning/AI approaches for the aiding of diagnosis, biomarker extraction and progression monitoring of multiple sclerosis using speech recordings. A corpus of 65 MS-positive and 66 healthy individuals reading the same text aloud was used for targeted acoustic feature extraction utilizing automatic phoneme segmentation. A series of binary classification models was trained, tuned, and evaluated regarding their Accuracy and area-under-the-curve. RESULTS The Random Forest model performed best, achieving an Accuracy of 0.82 on the validation dataset and an area-under-the-curve of 0.76 across 5 k-fold cycles on the training dataset. 5 out of 7 acoustic features were statistically significant. CONCLUSION Machine learning and artificial intelligence in automatic analyses of voice recordings for aiding multiple sclerosis diagnosis and progression tracking seems promising. Further clinical validation of these methods and their mapping onto multiple sclerosis progression is needed, as well as a validating utility for English-speaking populations.
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Affiliation(s)
- E Svoboda
- Institute of Formal and Applied Linguistics, Faculty of Mathematics and Physics, Charles University, Prague, Czech Republic; Institute of Phonetics, Faculty of Arts, Charles University, Prague, Czech Republic
| | - T Bořil
- Institute of Phonetics, Faculty of Arts, Charles University, Prague, Czech Republic
| | - J Rusz
- Department of Circuit Theory, Faculty of Electrical Engineering, Czech Technical University in Prague, Prague, Czech Republic; Department of Neurology and Center of Clinical Neuroscience, First Faculty of Medicine, Charles University and General University Hospital, Prague, Czech Republic; Department of Neurology & ARTORG Center, Inselspital, Bern University Hospital, University of Bern, Switzerland
| | - T Tykalová
- Department of Circuit Theory, Faculty of Electrical Engineering, Czech Technical University in Prague, Prague, Czech Republic
| | - D Horáková
- Department of Neurology and Center of Clinical Neuroscience, First Faculty of Medicine, Charles University and General University Hospital, Prague, Czech Republic
| | - C R G Guttmann
- Center for Neurological Imaging, Brigham & Women's Hospital and Harvard Medical School, USA
| | - K B Blagoev
- Department of Biophysics, Johns Hopkins University, Baltimore, MD, 21218, USA
| | - H Hatabu
- Department of Radiology, Brigham and Women's Hospital, Harvard Medical School, Boston, MA, USA
| | - V I Valtchinov
- Center for Evidence-Based Imaging, USA; Department of Radiology, Brigham and Women's Hospital, Harvard Medical School, Boston, MA, USA; Department of Biomedical Informatics, Harvard Medical School, Boston, MA, USA.
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Hida T, Lydon C, Hatabu H, Johnson B, Awad M, Nishino M. P1.01-35 Tumor Volume Analysis In ALK-Rearranged NSCLC Treated with Crizotinib: Identifying an Early Marker for Clinical Outcome. J Thorac Oncol 2018. [DOI: 10.1016/j.jtho.2018.08.591] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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Nishino M, Adeni A, Lydon C, Hatabu H, Jänne P, Hodi F, Awad M. P1.01-055 Spectrum of Early Progression in Advanced NSCLC Patients Treated with PD-1 Inhibitors: Identifying Markers for Poor Outcome. J Thorac Oncol 2017. [DOI: 10.1016/j.jtho.2017.09.709] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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Khandelwal A, Sholl LM, Araki T, Ramaiya NH, Hatabu H, Nishino M. Patterns of metastasis and recurrence in thymic epithelial tumours: longitudinal imaging review in correlation with histological subtypes. Clin Radiol 2016; 71:1010-1017. [PMID: 27267746 DOI: 10.1016/j.crad.2016.05.007] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2016] [Revised: 04/26/2016] [Accepted: 05/09/2016] [Indexed: 02/05/2023]
Abstract
AIM To determine the patterns of metastasis and recurrence in thymic epithelial tumours based on longitudinal imaging studies, and to correlate the patterns with World Health Organization (WHO) histological classifications. MATERIALS AND METHODS Seventy-seven patients with histopathologically confirmed thymomas (n=62) and thymic carcinomas (n=15) who were followed with cross-sectional follow-up imaging after surgery were retrospectively studied. All cross-sectional imaging studies during the disease course were reviewed to identify metastasis or recurrence. The sites of involvement and the time of involvement measured from surgery were recorded. RESULTS Metastasis or recurrence was noted in 24 (31%) of the 77 patients. Patients with metastasis or recurrence were significantly younger than those without (median age: 46 versus 60, respectively; p=0.0005), and more commonly had thymic carcinomas than thymomas (p=0.002). The most common site of involvement was the pleura (17/24), followed by the lung (9/24), and thoracic nodes (9/24). Abdominopelvic involvement was noted in 12 patients, most frequently in the liver (n=8). Lung metastasis was more common in thymic carcinomas than thymomas (p=0.0005). Time from surgery to the development of metastasis or recurrence was shortest in thymic carcinoma, followed by high-risk thymomas, and was longest in low-risk thymoma (median time in months: 25.1, 68.8, and not reached, respectively; p=0.0015). CONCLUSIONS The patterns of metastasis and recurrence of thymic epithelial tumours differ significantly across histological subgroups, with thymic carcinomas more commonly having metastasis with shorter length of time after surgery. The knowledge of different patterns of tumour spread may contribute to further understanding of the biological and clinical behaviours of these tumours.
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Affiliation(s)
- A Khandelwal
- Department of Radiology, Brigham and Women's Hospital and Dana-Farber Cancer Institute, 450 Brookline Ave., Boston, MA 02215, USA
| | - L M Sholl
- Department of Pathology, Brigham and Women's Hospital and Dana-Farber Cancer Institute, 450 Brookline Ave., Boston, MA 02215, USA
| | - T Araki
- Department of Radiology, Brigham and Women's Hospital and Dana-Farber Cancer Institute, 450 Brookline Ave., Boston, MA 02215, USA
| | - N H Ramaiya
- Department of Radiology, Brigham and Women's Hospital and Dana-Farber Cancer Institute, 450 Brookline Ave., Boston, MA 02215, USA
| | - H Hatabu
- Department of Radiology, Brigham and Women's Hospital and Dana-Farber Cancer Institute, 450 Brookline Ave., Boston, MA 02215, USA
| | - M Nishino
- Department of Radiology, Brigham and Women's Hospital and Dana-Farber Cancer Institute, 450 Brookline Ave., Boston, MA 02215, USA.
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van der Hulle T, den Exter PL, Planquette B, Meyer G, Soler S, Monreal M, Jiménez D, Portillo AK, O'Connell C, Liebman HA, Shteinberg M, Adir Y, Tiseo M, Bersanelli M, Abdel-Razeq HN, Mansour AH, Donnelly OG, Radhakrishna G, Ramasamy S, Bozas G, Maraveyas A, Shinagare AB, Hatabu H, Nishino M, Huisman MV, Klok FA. Risk of recurrent venous thromboembolism and major hemorrhage in cancer-associated incidental pulmonary embolism among treated and untreated patients: a pooled analysis of 926 patients. J Thromb Haemost 2016; 14:105-13. [PMID: 26469193 PMCID: PMC7480998 DOI: 10.1111/jth.13172] [Citation(s) in RCA: 88] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2015] [Accepted: 09/30/2015] [Indexed: 12/17/2022]
Abstract
UNLABELLED ESSENTIALS: We performed a pooled analysis of 926 patients with cancer-associated incidental pulmonary embolism (IPE). Vitamin K antagonists (VKA) are associated with a higher risk of major hemorrhage. Recurrence risk is comparable after subsegmental and more proximally localized IPE. Our results support low molecular weight heparins over VKA and similar management of subsegmental IPE. BACKGROUND Incidental pulmonary embolism (IPE) is defined as pulmonary embolism (PE) diagnosed on computed tomography scanning not performed for suspected PE. IPE has been estimated to occur in 3.1% of all cancer patients and is a growing challenge for clinicians and patients. Nevertheless, knowledge about the treatment and prognosis of cancer-associated IPE is scarce. We aimed to provide the best available evidence on IPE management. METHODS Incidence rates of symptomatic recurrent venous thromboembolism (VTE), major hemorrhage, and mortality during 6-month follow-up were pooled using individual patient data from studies identified by a systematic literature search. Subgroup analyses based on cancer stage, thrombus localization, and management were performed. RESULTS In 926 cancer patients with IPE from 11 cohorts, weighted pooled 6-month risks of recurrent VTE, major hemorrhage and mortality were 5.8% (95% confidence interval [CI] 3.7-8.3%), 4.7% (95% CI 3.0-6.8%), and 37% (95% CI 28-47%). VTE recurrence risk was comparable under low molecular weight heparins (LMWH) and vitamin K antagonists (VKAs) (6.2% vs. 6.4%; hazard ratio [HR] 0.9; 95% CI 0.3-3.1), while 12% in untreated patients (HR 2.6; 95% CI 0.91-7.3). Risk of major hemorrhage was higher under VKAs than under LMWH (13% vs. 3.9%; HR 3.9; 95% CI 1.6-10). VTE recurrence risk was comparable in patients with an subsegmental IPE and those with a more proximally localized IPE (HR 1.1; 95% CI 0.50-2.4). CONCLUSION These results support the current recommendation to anticoagulate cancer-associated IPE with LMWH and argue against different management of subsegmental IPE.
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Affiliation(s)
- T van der Hulle
- Department of Thrombosis and Hemostasis, Leiden University Medical Center, Leiden, the Netherlands
| | - P L den Exter
- Department of Thrombosis and Hemostasis, Leiden University Medical Center, Leiden, the Netherlands
| | - B Planquette
- Department of Respiratory and Intensive Care Medicine, Hôpital Européen Georges-Pompidou, Université Paris Descartes, INSERM U 965, Paris, France
| | - G Meyer
- Department of Respiratory and Intensive Care Medicine, Hôpital Européen Georges-Pompidou, Université Paris Descartes, INSERM U 965, Paris, France
| | - S Soler
- Department of Internal Medicine, Hospital Sant Jaume, Olot, Gerona, Spain
| | - M Monreal
- Department of Internal Medicine, Hospital Universitari Germans Trias i Pujol, Barcelona, Spain
| | - D Jiménez
- Respiratory Department, Ramon y Cajal Hospital, IRYCIS and Alcala de Henares University, Madrid, Spain
| | - A K Portillo
- Respiratory Department, Ramon y Cajal Hospital, IRYCIS and Alcala de Henares University, Madrid, Spain
| | - C O'Connell
- Jane Anne Nohl Division of Hematology, Keck School of Medicine, University of Southern California, Los Angeles, CA, USA
| | - H A Liebman
- Jane Anne Nohl Division of Hematology, Keck School of Medicine, University of Southern California, Los Angeles, CA, USA
| | - M Shteinberg
- Pulmonology Institute, Faculty of Medicine, Carmel Medical Center, Technion, Israel Institute of Technology, Haifa, Israel
- CF Center, Faculty of Medicine, Carmel Medical Center, Technion, Israel Institute of Technology, Haifa, Israel
| | - Y Adir
- Pulmonology Institute, Faculty of Medicine, Carmel Medical Center, Technion, Israel Institute of Technology, Haifa, Israel
| | - M Tiseo
- Medical Oncology Unit, University Hospital of Parma, Parma, Italy
| | - M Bersanelli
- Medical Oncology Unit, University Hospital of Parma, Parma, Italy
| | - H N Abdel-Razeq
- Department of Internal Medicine and Department of Radiology, King Hussein Cancer Center, Amman, Jordan
| | - A H Mansour
- Department of Internal Medicine and Department of Radiology, King Hussein Cancer Center, Amman, Jordan
| | - O G Donnelly
- Leeds Institute of Cancer and Pathology, University of Leeds and St James' Institute of Oncology, Leeds, UK
| | | | - S Ramasamy
- St James' Institute of Oncology, Leeds, UK
| | - G Bozas
- Queen's Centre for Oncology and Haematology, Castle Hill Hospital, Hull and East Yorkshire Hospitals NHS Trust, Cottingham, UK
| | - A Maraveyas
- Queen's Centre for Oncology and Haematology, Castle Hill Hospital, Hull and East Yorkshire Hospitals NHS Trust and Hull York Medical School, Cottingham, UK
| | - A B Shinagare
- Department of Radiology, Brigham and Women's Hospital and Dana-Farber Cancer Institute, Boston, MA, USA
| | - H Hatabu
- Department of Radiology, Brigham and Women's Hospital and Dana-Farber Cancer Institute, Boston, MA, USA
| | - M Nishino
- Department of Radiology, Brigham and Women's Hospital and Dana-Farber Cancer Institute, Boston, MA, USA
| | - M V Huisman
- Department of Thrombosis and Hemostasis, Leiden University Medical Center, Leiden, the Netherlands
| | - F A Klok
- Department of Thrombosis and Hemostasis, Leiden University Medical Center, Leiden, the Netherlands
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Nishino M, Jackman DM, DiPiro PJ, Hatabu H, Jänne PA, Johnson BE. Revisiting the relationship between tumour volume and diameter in advanced NSCLC patients: An exercise to maximize the utility of each measure to assess response to therapy. Clin Radiol 2014; 69:841-8. [PMID: 24857677 DOI: 10.1016/j.crad.2014.03.020] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2014] [Revised: 03/12/2014] [Accepted: 03/27/2014] [Indexed: 10/25/2022]
Abstract
AIM To revisit the presumed relationship between tumour diameter and volume in advanced non-small-cell lung cancer (NSCLC) patients, and determine whether the measured volume using volume-analysis software and its proportional changes during therapy matches with the calculated volume obtained from the presumed relationship and results in concordant response assessment. MATERIALS AND METHODS Twenty-three patients with stage IIIB/IV NSCLC with a total of 53 measurable lung lesions, treated in a phase II trial of erlotinib, were studied with institutional review board approval. Tumour volume and diameter were measured at baseline and at the first follow-up computed tomography (CT) examination using volume-analysis software. Using the measured diameter (2r) and the equation, calculated volume was obtained as (4/3)πr(3) at baseline and at the follow-up. Percent volume change was obtained by comparing to baseline for measured and calculated volumes, and response assessment was assigned. RESULTS The measured volume was significantly smaller than the calculated volume at baseline (median 11,488.9 mm(3) versus 17,148.6 mm(3); p < 0.0001), with a concordance correlation coefficient (CCC) of 0.7022. At follow-up, the measured volume was once again significantly smaller than the calculated volume (median 6573.5 mm(3) versus 9198.1 mm(3); p = 0.0022), with a CCC of 0.7408. Response assessment by calculated versus measured volume changes had only moderate agreement (weighted κ = 0.545), with discordant assessment results in 20% (8/40) of lesions. CONCLUSION Calculated volume based on the presumed relationship significantly differed from the measured volume in advanced NSCLC patients, with only moderate concordance in response assessment, indicating the limitations of presumed relationship.
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Affiliation(s)
- M Nishino
- Department of Radiology, Dana-Farber Cancer Institute and Brigham and Women's Hospital, 450 Brookline Ave., 75 Francis St., Boston, MA 02215, USA.
| | - D M Jackman
- Department of Medical Oncology and Department of Medicine, Dana-Farber Cancer Institute and Brigham and Women's Hospital, 450 Brookline Ave., Boston, MA 02215, USA
| | - P J DiPiro
- Department of Radiology, Dana-Farber Cancer Institute and Brigham and Women's Hospital, 450 Brookline Ave., 75 Francis St., Boston, MA 02215, USA
| | - H Hatabu
- Department of Radiology, Dana-Farber Cancer Institute and Brigham and Women's Hospital, 450 Brookline Ave., 75 Francis St., Boston, MA 02215, USA
| | - P A Jänne
- Department of Medical Oncology and Department of Medicine, Dana-Farber Cancer Institute and Brigham and Women's Hospital, 450 Brookline Ave., Boston, MA 02215, USA
| | - B E Johnson
- Department of Medical Oncology and Department of Medicine, Dana-Farber Cancer Institute and Brigham and Women's Hospital, 450 Brookline Ave., Boston, MA 02215, USA
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Araki T, Sholl LM, Gerbaudo VH, Hatabu H, Nishino M. Intrathymic cyst: clinical and radiological features in surgically resected cases. Clin Radiol 2014; 69:732-8. [PMID: 24824976 DOI: 10.1016/j.crad.2014.03.002] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2014] [Revised: 02/27/2014] [Accepted: 03/03/2014] [Indexed: 02/01/2023]
Abstract
AIM To investigate radiological and clinical characteristics of pathologically proven cases of intrathymic cysts. MATERIALS AND METHODS The study population consisted of 18 patients (five males, 13 females; median age 56 years) with pathologically confirmed intrathymic cysts who underwent thymectomy and had preoperative chest computed tomography (CT) available for review. The patient demographics, clinical presentation, and preoperative radiological diagnoses were reviewed. CT images were evaluated for shape, contour, location of the cysts and the presence of adjacent thymic tissue, mass effect, calcifications, and septa. The size and CT attenuations of the cysts were measured. RESULTS The most common CT features of intrathymic cysts included oval shape (9/18; 50%), smooth contour (12/18; 67%), midline location (11/18; 61%), the absence of visible adjacent thymic tissue (12/18; 67%), and the absence of calcification (16/18; 89%). The mean longest diameter and the longest perpendicular diameter were 25 mm (range 17-49 mm) and 19 mm (range 10-44 mm), respectively. The mean CT attenuation was 38 HU (range 6-62 HU) on contrast-enhanced CT, and was 45 HU (range 26-64 HU) on unenhanced CT (p = 0.41). The CT attenuation was >20 HU in 15 of 18 patients (83%). Preoperative radiological diagnosis included thymoma in 11 patients. CONCLUSION In surgically removed, pathologically proven cases of intrathymic cyst, the CT attenuation was >20 HU in most cases, leading to the preoperative diagnosis of thymoma. Awareness of the spectrum of imaging findings of the entity is essential to improve the diagnostic accuracy and patient management.
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Affiliation(s)
- T Araki
- Department of Radiology, Brigham and Women's Hospital, Harvard Medical School, 75 Francis St., Boston, MA, USA
| | - L M Sholl
- Department of Pathology, Brigham and Women's Hospital, 75 Francis St., Boston, MA, USA
| | - V H Gerbaudo
- Department of Radiology, Brigham and Women's Hospital, Harvard Medical School, 75 Francis St., Boston, MA, USA
| | - H Hatabu
- Department of Radiology, Brigham and Women's Hospital, Harvard Medical School, 75 Francis St., Boston, MA, USA
| | - M Nishino
- Department of Radiology, Brigham and Women's Hospital, Harvard Medical School, 75 Francis St., Boston, MA, USA; Department of Imaging, Dana-Farber Cancer Institute, Harvard Medical School, Boston, MA, USA.
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Lewis J, Mamata H, Tokuda J, Mishra P, Hermann G, Hatabu H, Nishino M, Mak R. TH-C-141-08: A Feasibility Study of the Utility of Dynamic Contrast-Enhanced MRI for Treatment Planning and Monitoring Treatment Response in Lung Stereotactic Body Radiation Therapy. Med Phys 2013. [DOI: 10.1118/1.4815776] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
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Kelly DM, Hasegawa I, Borders R, Hatabu H, Boiselle PM. High-Resolution CT Using MDCT: Comparison of Degree of Motion Artifact Between Volumetric and Axial Methods. AJR Am J Roentgenol 2004; 182:757-9. [PMID: 14975982 DOI: 10.2214/ajr.182.3.1820757] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
OBJECTIVE The purpose of this study was to compare the degree of motion artifact on high-resolution CT images obtained using volumetric and axial (nonvolumetric) CT methods. CONCLUSION Volumetric high-resolution CT is associated with significantly greater motion artifact compared with axial noncontiguous high-resolution imaging.
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Affiliation(s)
- D M Kelly
- Department of Radiology, Beth Israel Deaconess Medical Center and Harvard Medical School, 330 Brookline Ave., Boston, MA 02215, USA
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Zhang J, Hasegawa I, Hatabu H, Feller-Kopman D, Boiselle PM. Frequency and Severity of Air Trapping at Dynamic Expiratory CT in Patients with Tracheobronchomalacia. AJR Am J Roentgenol 2004; 182:81-5. [PMID: 14684517 DOI: 10.2214/ajr.182.1.1820081] [Citation(s) in RCA: 38] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
Abstract
OBJECTIVE The purpose of this study was to compare the frequency and severity of air trapping in patients with and without tracheobronchomalacia using dynamic expiratory volumetric CT. MATERIALS AND METHODS The study group consisted of 20 subjects, including 10 patients with bronchoscopically proven tracheobronchomalacia and 10 control subjects of similar ages without tracheobronchomalacia. All 20 subjects underwent MDCT performed at the end of deep inspiration and during dynamic expiration. The images were analyzed at three lung levels, and the extent of air trapping was assessed visually using a 5-point scale. For each subject, a total air-trapping score was derived by summing the values for the three lung levels (possible range, 0-12). Statistical analysis was performed using the Mann-Whitney U test. RESULTS In the tracheobronchomalacia group, 10 (100%) of 10 patients showed air trapping, with a median score of 5 (range, 2-12). In the control group, six (60%) of 10 subjects showed air trapping, with a median score of 2 (range, 0-3). The median total air-trapping score was significantly higher (p < 0.001) for the tracheobronchomalacia group compared with the control group. Excessive central airway collapse (expiratory reduction in cross-sectional area of > 50%) was seen on CT scans in all tracheobronchomalacia patients but in none of the control subjects. CONCLUSION Air trapping was observed with a higher frequency and greater severity in patients with tracheobronchomalacia than in a control group of patients of similar ages without tracheobronchomalacia.
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Affiliation(s)
- J Zhang
- Department of Radiology, Beth Israel Deaconess Medical Center and Harvard Medical School, 330 Brookline Ave., Boston, MA 02215, USA
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Schuster ME, Fishman JE, Copeland JF, Hatabu H, Boiselle PM. Pulmonary Embolism in Pregnant Patients:A Survey of Practices and Policies for CT Pulmonary Angiography. AJR Am J Roentgenol 2003; 181:1495-8. [PMID: 14627562 DOI: 10.2214/ajr.181.6.1811495] [Citation(s) in RCA: 57] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
OBJECTIVE We surveyed the practices and policies of the radiology departments of the Society of Thoracic Radiology members regarding the use of CT pulmonary angiography in pregnant patients suspected of having pulmonary embolism. MATERIALS AND METHODS Surveys were mailed electronically to the 403 members of the Society of Thoracic Radiology (403 addresses). Respondents were asked to send one response from each institution or department. Information gathered included use of CT angiography in relation to ventilation-perfusion imaging in pregnant patients, written policies, informed consent procedures, and modifications of standard protocols for dose reduction. RESULTS Fifty-seven members responded; 43 (75%) reported that they perform CT angiography in pregnant patients suspected of having pulmonary embolism. Of the 43 respondents who perform CT angiography in pregnant patients, 23 (53%) generally perform CT angiography as the initial study rather than ventilation-perfusion scanning, 26 (60%) require informed consent from the patient, seven (16%) have a written policy concerning CT angiography in pregnant patients, and 17 (40%) modify standard imaging protocols for pregnant patients. The most common modification for dose reduction is decreasing the scanning area along the z-axis. CONCLUSION Most respondents perform CT angiography in pregnant patients suspected of having pulmonary embolism, but their policies and practices vary considerably.
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Affiliation(s)
- M E Schuster
- Department of Radiology, Beth Israel Deaconess Medical Center and Harvard Medical School, 330 Brookline Ave., Boston, MA 02215, USA
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Uematsu H, Dougherty L, Takahashi M, Ohno Y, Nakatsu M, Song HK, Ferrari VA, Gefter WB, Schnall MD, Hatabu H. Pulmonary MR angiography with contrast agent at 4 Tesla: a preliminary result. Magn Reson Med 2001; 46:1028-30. [PMID: 11675658 DOI: 10.1002/mrm.1292] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
In this study, pulmonary MR angiography (MRA) using a tailored coil at 4 Tesla in conjunction with an intravenous injection of contrast agent is described. Three-dimensional gradient-echo images were obtained during the intravenous injection of 0.05, 0.1, and 0.2 mmol/kg body weight of gadodiamide to investigate the signal enhancement effect of the contrast agent in pulmonary arteries qualitatively and quantitatively. In the qualitative analysis, the subsegmental branches were visualized on every dose. In the quantitative analysis, the average contrast-to-noise ratios (CNRs) of the main pulmonary arteries increased in a dose-dependent manner. However, the CNRs of segmental arteries did not increase as the dose of contrast agent increased, as observed at 1.5 Tesla MRI. These observations demonstrate the feasibility of delineating the pulmonary vasculature using a contrast agent; however, our results also suggest possible high-field-related disabilities that need to be overcome before high-field (> or =4 Tesla) MRI can be used to full advantage.
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Affiliation(s)
- H Uematsu
- Department of Radiology, University of Pennsylvania Medical Center, Philadelphia, Pennsylvania 19104-2649, USA
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Abstract
Hyperpolarized noble gases are a new class of MR contrast agent. Since the first hyperpolarized gas MR images of the lung were reported, there has been considerable interest in using hyperpolarized gas to obtain high spatial and temporal resolution images of the air spaces of the lung. In addition to static images of lung ventilation, new techniques are being developed using hyperpolarized gas to obtain dynamic, diffusion and oxygen concentration images of the lung. In this article, we review the potential clinical applications of pulmonary hyperpolarized gas MRI and discuss the preliminary findings in a variety of lung diseases. Hyperpolarized gas MRI has the potential to provide a comprehensive morphologic and functional assessment of the lung.
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Affiliation(s)
- M Salerno
- Department of Radiology, University of Virginia Health Sciences System, Charlottesville, VA 22908, USA
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Roberts DA, Rizi RR, Lipson DA, Ferrante MA, Bearn L, Rolf L, Baumgardner J, Yamomoto A, Hatabu H, Hansen-Flaschen J, Gefter WB, Schnall MD. Dynamic observation of pulmonary perfusion using continuous arterial spin-labeling in a pig model. J Magn Reson Imaging 2001; 14:175-80. [PMID: 11477677 DOI: 10.1002/jmri.1169] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
Abstract
The continuous arterial spin-labeling (CASL) method of perfusion MRI is used to observe pulmonary perfusion dynamically in an animal model. Specifically, a respiratory-triggered implementation of the CASL method is used with approximate spatial resolution of 0.9 x 1.8 x 5.0 mm (0.008 cc) and 2-minute temporal resolution. Perfusion MRI is performed dynamically during repeated balloon occlusion of a segmental pulmonary artery, as well as during pharmacological stimulation. A total of three Yorkshire pigs were studied. The results demonstrate the ability of the endogenous spin-labeling method to characterize the dynamic changes in pulmonary perfusion that occur during important physiological alterations.
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Affiliation(s)
- D A Roberts
- Department of Radiology, University of Pennsylvania Medical Center, Philadelphia, Pennsylvania 19104-4283, USA.
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15
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Ohno Y, Hatabu H, Takenaka D, Adachi S, Van Cauteren M, Sugimura K. Oxygen-enhanced MR ventilation imaging of the lung: preliminary clinical experience in 25 subjects. AJR Am J Roentgenol 2001; 177:185-94. [PMID: 11418424 DOI: 10.2214/ajr.177.1.1770185] [Citation(s) in RCA: 66] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
OBJECTIVE The purpose of this study was to show the feasibility of oxygen-enhanced MR ventilation imaging in a clinical setting with correlation to standard pulmonary function tests, high-resolution CT, and (81m)Kr ventilation scintigraphy. SUBJECTS AND METHODS Seven healthy volunteers, 10 lung cancer patients, and eight lung cancer patients with pulmonary emphysema were studied. A respiratory synchronized inversion-recovery single-shot turbo-spin-echo sequence (TE, 16; inversion time, 720 msec; interecho spacing, 4 msec) was used for data acquisition. The following paradigm of oxygen inhalation was used: 21% oxygen (room air), 100% oxygen, 21% oxygen. MR imaging data including maximum mean relative enhancement ratio and mean slope of relative enhancement were correlated with forced expiratory volume in 1 sec, diffusing lung capacity, high-resolution CT emphysema score, and mean distribution ratio of (81m)Kr ventilation scintigraphy. RESULTS Oxygen-enhanced MR ventilation images were obtained in all subjects. Maximum mean relative enhancement ratio and mean slope of relative enhancement of lung cancer patients were significantly decreased compared with those of the healthy volunteers (p < 0.0001, p < 0.0001). The mean slope of relative enhancement in lung cancer patients with pulmonary emphysema was significantly lower than that of lung cancer patients without pulmonary emphysema (p < 0.0001). Maximum mean relative enhancement ratio (r(2) = 0.81) was excellently correlated with diffusing lung capacity. Mean slope of relative enhancement (r(2) = 0.74) was strongly correlated with forced expiratory volume in 1 sec. Maximum mean relative enhancement had good correlation with the high-resolution CT emphysema score (r(2) = 0.38). The maximum mean relative enhancement had a strong correlation with the distribution ratio (r(2) = 0.77). CONCLUSION Oxygen-enhanced MR ventilation imaging in human subjects showed regional changes in ventilation, thus reflecting regional lung function.
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Affiliation(s)
- Y Ohno
- Department of Radiology, Kobe University Graduate School of Medicine, 7-5-2 Kusunoki-cho, Chuo-ku, Kobe 650-0017, Japan
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16
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Abstract
An ultrafast MR sequence was used to measure changes in signal intensity during the first pass of intravascular contrast through the pulmonary circulation. From this, mean transit time, relative blood volume, and relative blood flow were calculated. Data were collected in an isogravitational plane in six healthy subjects. A slight but significant gradient in transit time was present, with faster times at the lung apex. A significant decrease in blood volume, compared with the lung base, was also seen in the apex. Significant decreases in blood volume and blood flow, compared with central portions of the lung, were seen in the lung periphery. Six additional subjects were imaged along a gravitational plane. A significant gradient in transit time was seen, with faster transit in dependent regions of the lung. MRI is able to evaluate regional differences in pulmonary perfusion with high spatial and temporal resolution. Magn Reson Med 46:166-171, 2001.
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Affiliation(s)
- D L Levin
- Department of Radiology, Beth Israel Deaconess Medical Center, Boston, Massachusetts, USA.
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17
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Abstract
The oxygen-enhanced magnetic resonance (MR) ventilation imaging is a new technique, and the full extent of its physiological significance has not been elucidated. This review article includes background on (1) respiratory physiology; (2) mechanism and optimization of oxygen-enhanced MR imaging technique; (3) recent applications in animal and human models; and (4) merits and demerits of the technique in comparison with hyperpolarized noble gas MR ventilation imaging. Application of oxygen-enhanced MR ventilation imaging to patients with pulmonary diseases has been very limited. However, we believe that further basic studies, as well as clinical applications of this new technique will define the real significance of oxygen-enhanced MR ventilation imaging in the future of pulmonary functional imaging and its usefulness for diagnostic radiology.
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Affiliation(s)
- Y Ohno
- Pulmonary Functional Imaging Research, Department of Radiology, University of Pennsylvania Medical Center, 3600 Market Street, Suite 370, Philadelphia, PA 19104-2649, USA.
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18
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Abstract
An understanding of fine normal lung morphology is important for effective pulmonary functional imaging. The lung specimens must be inflated. These include (a) unfixed, inflated lung specimen, (b) formaldehyde fixed lung specimen, (c) fixed, inflated dry lung specimen, and (d) histology specimen. Photography, magnified view, radiograph, computed tomography, and histology of these specimens are demonstrated. From a standpoint of diagnostic imaging, the main normal lung structures consist of airways (bronchi and bronchioles), alveoli, pulmonary vessels, secondary pulmonary lobules, and subpleural pulmonary lymphatic channels. This review summarizes fine radiologic normal lung morphology as an aid to effective pulmonary functional imaging.
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Affiliation(s)
- H Itoh
- Department of Radiology, Fukui Medical University, 23 Shimoaizuki, Matsuoka-cho, Yoshida-gun, Fukui 910-1193, Japan.
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19
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Abstract
Recent advances in magnetic resonance pulmonary perfusion imaging are reviewed, focusing on magnetic resonance perfusion imaging using gadolinium contrasts agents or spin labeling of blood using naturally flowing spins as the source of intravascular signal. These recent developments in magnetic resonance imaging have made it possible to analyze data quantitatively which holds significant potential for clinical imaging of lung perfusion and opens windows to functional MR imaging of the lung. We believe that fast magnetic resonance functional imaging will play an important role in the assessment of pulmonary function and the pulmonary disease process.
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Affiliation(s)
- H Uematsu
- Department of Radiology, Pulmonary Functional Imaging Research, University of Pennsylvania Medical Center, 3600 Market Street, Suite 370, Philadelphia, PA 19104-2649, USA.
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20
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Abstract
We have recently demonstrated a non-invasive technique to visualize pulmonary ventilation in humans with inhalation of molecular oxygen as a paramagnetic contrast agent. In the current study, T1 shortening of lung tissue by inhalation of oxygen was observed (P<0.001). The T1 values of lung tissue were also correlated with arterial blood oxygen pressure (PaO(2)) in a pig, resulting in excellent correlation (r(2)=0.997). Dynamic wash-in and wash-out MR ventilation images as well as dynamic wash-in wash-out signal intensity versus time curves were obtained. The mean wash-in decay constants were 26.8+/-10.5 s in the right lung, and 26.3+/-9.5 s in the left lung. The mean wash-out decay constants were 23.3+/-11.3 s in the right lung, and 20.8+/-10.5 s in the left lung. Dynamic assessment of pulmonary ventilation is feasible using oxygen-enhanced MR imaging, which could provide dynamic MR ventilation-perfusion imaging in combination with recently developed MR perfusion imaging technique, and thus a robust tool for the study of pulmonary physiology and pathophysiology.
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Affiliation(s)
- H Hatabu
- Department of Radiology, Beth Israel Deaconess Medical Center and Harvard Medical School, Boston, MA, USA.
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21
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Abstract
The MR signal intensity change in the pulmonary parenchyma during the cardiac cycle was studied using HASTE sequence in volunteers. In addition, the potential to assess pulmonary perfusion abnormality by subtraction between diastolic and systolic HASTE images was tested in a pig model of pulmonary embolism. Signal intensity decreased in systole while it increased gradually in diastole. In a pig model with pulmonary embolism, subtracted images could identify the perfusion abnormality. Thus, subtraction of diastolic and systolic HASTE images has the potential to detect pulmonary perfusion abnormality. The technique may provide a new simple method for evaluating pulmonary perfusion.
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Affiliation(s)
- E Tadamura
- Department of Radiology, Beth Israel Deaconess Medical Center, 330 Brookline Ave, Boston, MA 02215, USA.
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22
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Ohno Y, Adachi S, Motoyama A, Kusumoto M, Hatabu H, Sugimura K, Kono M. Multiphase ECG-triggered 3D contrast-enhanced MR angiography: utility for evaluation of hilar and mediastinal invasion of bronchogenic carcinoma. J Magn Reson Imaging 2001; 13:215-24. [PMID: 11169827 DOI: 10.1002/1522-2586(200102)13:2<215::aid-jmri1032>3.0.co;2-2] [Citation(s) in RCA: 50] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022] Open
Abstract
The purpose of this study was to evaluate the usefulness of cardiac synchronized magnetic resonance angiography [electrocardiographically (ECG)-triggered MRA] for improving image quality and detection of hilar and mediastinal invasion of bronchogenic carcinoma. Fifty patients, suspected of having hilar or mediastinal invasion of bronchogenic carcinoma, underwent contrast-enhanced computed tomography and MR imaging including conventional and ECG-triggered MRA. Twenty patients subsequently also underwent surgical resection. Vascular enhancement-to-background ratio (VBR), vascular enhancement-to-tumor ratio (VTR), signal-to-noise ratio (SNR), contrast-to-noise ratio (CNR) and image quality scores of thoracic vessels obtained with both MRA techniques were determined and compared. In addition, the diagnostic accuracy of tumor invasion of pulmonary vessels was compared. VBRs and VTRs of both MRA techniques were not significantly different. ECG-triggered MRA significantly improved SNRs and CNRs (P < 0.05). Two readers judged that overall image quality of ECG-triggered MRA was better than that of conventional MRA (kappa > or = 0.41). In conclusion, ECG-triggered MRA improves the image quality and the detection of hilar and mediastinal invasion of bronchogenic carcinoma.
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Affiliation(s)
- Y Ohno
- Department of Radiology, Kobe University School of Medicine, Chuo-ku, Kobe 650-0017, Japan.
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23
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Abstract
The STAR-HASTE sequence has been shown to be useful for perfusion imaging in areas that are plagued by magnetic susceptibility artifacts. Pulmonary perfusion imaging with this technique was attempted in this study. Quantitative analysis was also conducted, using an appropriate kinetic model in one subject. In six healthy subjects, gradual enhancement was observed in pulmonary artery to distal lung parenchyma when inflow time was increased. Our initial results suggest that noninvasive evaluation of pulmonary perfusion by magnetic resonance imaging without administration of an exogenous agent is possible.
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Affiliation(s)
- H Hatabu
- Department of Radiology, Beth Israel Deaconess Medical Center, Boston, Massachusetts, USA.
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24
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Hatabu H, Stock KW, Sher S, Edinburgh KJ, Levin DL, Garpestad E, Albert MS, Mai VM, Chen Q, Edelman RR. Magnetic resonance imaging of the thorax. Past, present, and future. Radiol Clin North Am 2000; 38:593-620, x. [PMID: 10855264 DOI: 10.1016/s0033-8389(05)70187-1] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
Magnetic resonance imaging is a valuable modality of extreme flexibility for specific problem-solving capability in the thorax. This article reviews MR applications in the imaging of great vessels, which are currently the most important applications in the thorax; other established applications in the thorax; and pulmonary functional MR imaging.
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Affiliation(s)
- H Hatabu
- University of Pennsylvania Medical Center, Philadelphia 19104, USA
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25
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Mai VM, Chen Q, Li W, Hatabu H, Edelman RR. Effect of respiratory phases on MR lung signal intensity and lung conspicuity using segmented multiple inversion recovery turbo spin echo (MIR-TSE). Magn Reson Med 2000; 43:760-3. [PMID: 10800043 DOI: 10.1002/(sici)1522-2594(200005)43:5<760::aid-mrm20>3.0.co;2-m] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
The purpose of this study was to determine the effect of respiratory phase on signal intensity of the lung. Lung images were obtained from eleven healthy human volunteers using a multiple inversion recovery segmented turbo spin echo sequence (MIR-TSE). MIR exploits the difference in T(1) between different tissues to effectively null signal contributions from fat and muscle for improved visualization of the lung. The volunteers were asked to perform breath-holding on end inspiration or end expiration. There was a significant decrease in signal intensity of the lung with average SNR of 7.3 +/- 0.9 vs. 14.4 +/- 0.8 for coronal slices, and 9.5 +/-1.5 vs. 16.0 +/-2.4 for sagittal breath-hold images acquired during end inspiration compared with end expiration. It is concluded that MRI of the lungs should be performed during end expiration in order to optimize image quality.
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Affiliation(s)
- V M Mai
- Department of Radiology, Beth Israel Deaconess Medical Center and Harvard School of Medicine, Boston, MA 02215, USA.
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26
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McAdams HP, Hatabu H, Donnelly LF, Chen Q, Tadamura E, MacFall JR. Novel techniques for MR imaging of pulmonary airspaces. Magn Reson Imaging Clin N Am 2000; 8:205-19. [PMID: 10730243] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/15/2023]
Abstract
Hyperpolarized gas- and molecular oxygen-enhanced MR imaging are two new techniques for high-resolution MR imaging of pulmonary airspaces. Both techniques produce excellent images in a safe, reproducible, and technically feasible manner. Because morphologic and functional information is obtained, and radiation is not used, these techniques may prove ideal for serially evaluating patients with a variety of lung diseases that affect pulmonary ventilation, such as cystic fibrosis, emphysema, asthma, or bronchiolitis obliterans syndrome in lung transplant recipients. At present, the greatest clinical experience is with hyperpolarized He-3-enhanced MR imaging. This technique is limited, however, by the limited availability of He-3, by its polarization requirements, and by the need to tune the MR system to the resonant frequency of the gas. There is less clinical experience with oxygen-enhanced MR imaging. Although this technique produces images with more inherent noise than hyperpolarized He-3 imaging, this problem can be overcome by signal averaging. Oxygen-enhanced imaging has the major advantages of lower cost and ready availability. For oxygen-enhanced imaging, the MR imaging system does not need to be readjusted; imaging is performed at the conventional hydrogen proton frequency.
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Affiliation(s)
- H P McAdams
- Department of Radiology, Duke University Medical Center, Durham, North Carolina, USA.
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27
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Nakatsu M, Hatabu H, Itoh H, Morikawa K, Miki Y, Kasagi K, Shimono T, Shoji K, Shimada Y, Imamura M, Konishi J. Comparison of short inversion time inversion recovery (STIR) and fat-saturated (chemsat) techniques for background fat intensity suppression in cervical and thoracic MR imaging. J Magn Reson Imaging 2000; 11:56-60. [PMID: 10676621 DOI: 10.1002/(sici)1522-2586(200001)11:1<56::aid-jmri8>3.0.co;2-d] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
Abstract
The purpose of this study was to compare short inversion time inversion recovery (STIR) fast spin-echo (FSE), and fat-saturated T2-weighted FSE sequences in terms of uniformity of fat suppression and lesion conspicuity for magnetic resonance (MR) imaging of the neck and thorax. STIR FSE and fat-saturated T2-weighted FSE images were scored for uniformity of fat suppression (n = 40) and lesion conspicuity (n = 35). Five-point rank score analyses were utilized by three experienced radiologists. The mean scores of STIR and fat-saturated FSE techniques for uniformity of fat suppression were 4.3 and 2.3, respectively (P < 0.0001). The mean scores of STIR and fat-saturated FSE techniques for lesion conspicuity were 4.2 and 3.5, respectively (P < 0.0001). Insufficient fat suppression was prominent in the mandible, supraclavicular region, anterior mediastinum, epipericardial fat, and subdiaphragmatic fat. In addition, fat-saturated T2-weighted FSE showed inadvertent water suppression in 25%. The STIR FSE technique was superior to the fat-saturated FSE technique for cervical and thoracic MR imaging.
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Affiliation(s)
- M Nakatsu
- Department of Nuclear Medicine and Diagnostic Imaging, Kyoto University Hospital, Japan
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28
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Chen Q, Levin DL, Kim D, David V, McNicholas M, Chen V, Jakob PM, Griswold MA, Goldfarb JW, Hatabu H, Edelman RR. Pulmonary disorders: ventilation-perfusion MR imaging with animal models. Radiology 1999; 213:871-9. [PMID: 10580969 DOI: 10.1148/radiology.213.3.r99dc31871] [Citation(s) in RCA: 77] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
PURPOSE To demonstrate the capability of magnetic resonance (MR) imaging to assess alteration in regional pulmonary ventilation and perfusion with animal models of airway obstruction and pulmonary embolism. MATERIALS AND METHODS Airway obstruction was created by inflating a 5-F balloon catheter into a secondary bronchus. Pulmonary emboli were created by injecting thrombi into the inferior vena cava. Regional pulmonary ventilation was assessed with 100% oxygen as a T1 contrast agent. Regional pulmonary perfusion was assessed with a two-dimensional fast low-angle shot, or FLASH, sequence with short repetition and echo times after intravenous administration of gadopentetate dimeglumine. RESULTS Matched ventilation and perfusion abnormalities were identified in all animals with airway obstruction. MR perfusion defects without ventilation abnormalities were seen in all animals with pulmonary emboli. CONCLUSION Ventilation and perfusion MR imaging are able to provide regional pulmonary functional information with high spatial and temporal resolution. The ability of MR imaging to assess both the magnitude and regional distribution of pulmonary functional impairment could have an important effect on the evaluation of lung disease.
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Affiliation(s)
- Q Chen
- Dept of Radiology, Beth Israel Deaconess Medical Center, Boston, MA 02215 USA.
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29
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Abstract
The feasibility of qualitative assessment of pulmonary perfusion using dynamic contrast enhanced MRI with ultra-short TE has recently been demonstrated. In the current study, quantitative analysis was attempted based on the indicator dilution principle using a pig model of pulmonary embolism. The results were compared with the absolute pulmonary perfusion obtained with colored microspheres. The inverse of apparent mean transit time (1/tau(app)), distribution volume (V), and V/tau(app) were correlated well with the absolute lung perfusion. This study demonstrates that MR has the potential to evaluate pulmonary perfusion quantitatively. Magn Reson Med 42:1033-1038, 1999.
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Affiliation(s)
- H Hatabu
- Department of Radiology, Beth Israel Deaconess Medical Center, and Harvard Medical School, Boston, MA 02215, USA.
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30
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Hatabu H, Stock KW, Sher S, Edinburgh KJ, Levin DL, Garpestad E, Albert MS, Mai VM, Chen Q, Edelman RR. Magnetic resonance imaging of the thorax. Past, present, and future. Clin Chest Med 1999; 20:775-803, viii-ix. [PMID: 10587798 DOI: 10.1016/s0272-5231(05)70255-0] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
Abstract
Magnetic resonance is a valuable modality of extreme flexibility for specific problem-solving capability in the thorax. This article reviews MR applications in the imaging of great vessels, which are currently the most important applications in the thorax; other established applications in the thorax; and pulmonary functional MR imaging.
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Affiliation(s)
- H Hatabu
- Department of Radiology, Beth Israel Deaconess Medical Center, Boston, Massachusetts, USA
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31
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Shimono T, Hatabu H, Kasagi K, Miki Y, Nishizawa S, Misaki T, Hiraga A, Konishi J. Rapid progression of pituitary hyperplasia in humans with primary hypothyroidism: demonstration with MR imaging. Radiology 1999; 213:383-8. [PMID: 10551216 DOI: 10.1148/radiology.213.2.r99nv02383] [Citation(s) in RCA: 39] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
PURPOSE To use magnetic resonance (MR) imaging to evaluate the morphologic changes of the pituitary gland during the development of hypothyroidism. MATERIALS AND METHODS Fourteen patients who had undergone thyroidectomy were evaluated before radioactive iodine 131 therapy. In each patient, MR imaging and measurement of serum hormone levels were performed twice: 5 weeks before 131I treatment as the "euthyroid state" with thyroid hormone supplementation and on the day of 131I treatment as the "hypothyroid state" after a 3-week depletion of thyroid hormone supplements. Nine healthy volunteers also underwent MR imaging twice at an interval of 5 weeks. Pituitary volume and the relative signal intensity ratio of the anterior pituitary to the pons were measured. The shape and signal intensity of the pituitary gland were also visually assessed. The paired Student t test was used to evaluate the significance of the data. A P value less than .05 indicated a statistically significant difference. RESULTS The patients had significantly larger pituitary volume in the hypothyroid state than in the euthyroid state both quantitatively (P < .001) and visually. No significant differences were found in the relative signal intensity ratios of the anterior pituitary to the pons. In healthy volunteers, no significant differences in pituitary volumes or signal intensity were found between the two MR images. CONCLUSION Rapid progression of hyperplasia of the anterior pituitary may occur with acute development of hypothyroidism.
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Affiliation(s)
- T Shimono
- Department of Nuclear Medicine and Radiology, Faculty of Medicine, Kyoto University, Japan.
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32
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Abstract
The objective of this study was to measure T2* values of the normal human lung in vivo during breathhold using a rapid gradient-echo sequence with ultra-short echo times (TE). A sagittal slice of the right lung was imaged in six volunteers with various TE ranging from 0.5 ms to 5 ms using a clinical 1.5 Tesla MR scanner. T2* values were calculated in a region of interest in the dependent and non-dependent lung. In the dependent lung, T2* values of 1.1 ms+/-0.15 ms were measured, and in the non-dependent lung, 0.86 ms+/-0.11 (p < 0.01). T2* measurements of the normal human lung during breathhold are feasible with a clinical MR unit. The short T2* values require the use of very short TE times (< 2.5 ms) in gradient-echo sequences to obtain adequate signal intensity from lung tissue.
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Affiliation(s)
- K W Stock
- Department of Radiology, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA 02215, USA
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33
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Abstract
Lung ventilation imaging using inhaled oxygen as a contrast medium was performed using both a 0.2 and a 1.5 T clinical magnetic resonance (MR) scanner in eight volunteers. Signal-to-noise-ratios (SNRs) of the ventilation images as well as T1 values of the lung acquired with inhalation of 100% oxygen and room air were calculated. The SNR was 9.7 +/- 3.0 on the 0.2 T MR system and 69.5 +/- 28.8 on the 1.5 T system (P < 0.001). The mean T1 value on the 0.2 T MR system with subjects breathing room air was 632 +/- 54 msec; with 100% oxygen, it was 586 +/- 41 msec (P < 0.01). At 1.5 T, the mean values were 904 +/- 99 msec and 790 +/- 114 msec, respectively (P < 0.0001). We conclude that MR oxygen-enhanced ventilation imaging of the lung is feasible with an open configured 0.2 T MR system.
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Affiliation(s)
- K W Stock
- Department of Radiology, Beth Israel Deaconess Medical Center and Harvard Medical School, Boston, MA 02215, USA
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34
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Hatabu H, Chen Q, Levin DL, Tadamura E, Edelman RR. Ventilation-perfusion MR imaging of the lung. Magn Reson Imaging Clin N Am 1999; 7:379-92, x. [PMID: 10382168] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/13/2023]
Abstract
The assessment of regional ventilation in human lungs is important for the diagnosis and evaluation of a variety of pulmonary disorders, including pulmonary emphysema, diffuse lung disease (e.g., sarcoidosis, and pulmonary fibrosis), lung cancer, and pulmonary embolism. This article introduces new MR imaging techniques of pulmonary ventilation and perfusion that will provide a framework for assessing regional pulmonary functions of the lung.
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Affiliation(s)
- H Hatabu
- Department of Radiology, Harvard University Medical School, Boston, Massachusetts, USA.
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35
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Abstract
Imaging of lung perfusion using contrast-enhanced dynamic magnetic resonance (MR) was performed in both the supine and prone positions in six volunteers. Regions of interest (ROIs) were chosen in the dependent and non-dependent portions of the right lung. The percentage increase in signal intensity (SI) and the mean slope were calculated. In the supine position, the dorsal ROI had a greater increase in SI (236.0% vs. 156.9%, P < 0.05) and a faster rise in the slope of enhancement (55.1%/sec vs. 30.1%/sec, P < 0.05) than the ventral ROI. After changing to the prone position, higher peak enhancement (234.3% vs. 177.4%, P < 0.05) and faster slopes (59.6%/sec vs. 35.3%/sec, P < 0.05) shifted to the anterior ROI. We conclude that dynamic contrast-enhanced MR imaging is sensitive to demonstrate gravitationally dependent differences in lung perfusion.
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Affiliation(s)
- K W Stock
- Beth Israel Deaconess Medical Center and Harvard Medical School, Boston, Massachusetts 02215, USA
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36
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Edinburgh KJ, Levin DL, Hatabu H. Quiz case 6. Bronchiolitis obliterans organizing pneumonia (BOOP). Eur J Radiol 1999; 30:39-41. [PMID: 10389011 DOI: 10.1016/s0720-048x(99)00024-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Affiliation(s)
- K J Edinburgh
- Department of Radiology, Beth Israel Deaconess Medical Center, Boston, MA 02215, USA
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37
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Hatabu H, Alsop DC, Listerud J, Bonnet M, Gefter WB. T2* and proton density measurement of normal human lung parenchyma using submillisecond echo time gradient echo magnetic resonance imaging. Eur J Radiol 1999; 29:245-52. [PMID: 10399610 DOI: 10.1016/s0720-048x(98)00169-7] [Citation(s) in RCA: 144] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
OBJECTIVE To obtain T2* and proton density measurements of normal human lung parenchyma in vivo using submillisecond echo time (TE) gradient echo (GRE) magnetic resonance (MR) imaging. MATERIALS AND METHODS Six normal volunteers were scanned using a 1.5-T system equipped with a prototype enhanced gradient (GE Signa, Waukausha, WI). Images were obtained during breath-holding with acquisition times of 7-16 s. Multiple TEs ranging from 0.7 to 2.5 ms were tested. Linear regression was performed on the logarithmic plots of signal intensity versus TE, yielding measurements of T2* and proton density relative to chest wall muscle. Measurements in supine and prone position were compared, and effects of the level of lung inflation on lung signal were also evaluated. RESULTS The signal from the lung parenchyma diminished exponentially with prolongation of TE. The measured T2* in six normal volunteers ranged from 0.89 to 2.18 ms (1.43 +/- 0.41 ms, mean +/- S.D.). The measured relative proton density values ranged between 0.21 and 0.45 (0.29 +/- 0.08, mean +/- S.D.). Calculated T2* values of 1.46 +/- 0.50, 1.01 +/- 0.29 and 1.52 +/- 0.18 ms, and calculated relative proton densities of 0.20 +/- 0.03, 0.32 +/- 0.13 and 0.35 +/- 0.10 were obtained from the anterior, middle and posterior portions of the supine right lung, respectively. The anterior-posterior proton density gradient was reversed in the prone position. There was a pronounced increase in signal from lung parenchyma at maximum expiration compared with maximum inspiration. The ultrashort TE GRE technique yielded images demonstrating signal from lung parenchyma with minimal motion-induced noise. CONCLUSION Quantitative in vivo measurements of lung T2* and relative proton density in conjunction with high-signal parenchymal images can be obtained using a set of very rapid breath-hold images with a recently developed ultrashort TE GRE sequence.
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Affiliation(s)
- H Hatabu
- Department of Radiology, University of Pennsylvania Medical Center, Philadelphia 19104, USA
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Affiliation(s)
- H Hatabu
- Department of Radiology, Beth Israel Deaconess Medical Center, Boston, MA 02215, USA.
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Hatabu H, Gaa J, Tadamura E, Edinburgh KJ, Stock KW, Garpestad E, Edelman RR. MR imaging of pulmonary parenchyma with a half-Fourier single-shot turbo spin-echo (HASTE) sequence. Eur J Radiol 1999; 29:152-9. [PMID: 10374663 DOI: 10.1016/s0720-048x(98)00167-3] [Citation(s) in RCA: 111] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
OBJECTIVE To evaluate the utility of a half-Fourier single-shot turbo spin-echo sequence (HASTE) at depicting lung parenchyma and lung pathology. METHODS AND PATIENTS A HASTE sequence was applied to five normal volunteers and 20 patients with various pulmonary disorders to depict the lung parenchyma. Images were acquired with ECG-triggering and breath-holding. In three volunteers, signal intensity measurements from lung parenchyma were performed using four sequences: (a) HASTE; (b) conventional spin echo; (c) fast spin echo; and (d) gradient echo. T2 maps were produced using the HASTE acquisition. RESULTS Minimal respiratory or cardiac motion artifacts were observed. The signal-to-noise ratios from lung parenchyma were 27.8 +/- 5.4, 22.0 +/- 3.0, 15.3 +/- 0.9, and 6.0 +/- 1.9 for HASTE, spin-echo, fast spin-echo, and gradient echo sequences, respectively. The scan time for HASTE was 302 ms for each slice. The T2 values in the right lung and the left lung were 61.2 +/- 4.1 and 79.1 +/- 8.9 ms in systole and 92.6 +/- 5.8 and 97.5 +/- 12.2 ms in diastole, respectively (P < 0.05 diastole versus systole). The HASTE sequence demonstrated clearly various pulmonary disorders, including lung cancer, hilar lymphadenopathy, metastatic pulmonary nodules as small as 3 mm, pulmonary hemorrhage, pulmonary edema and bronchial wall thickening in bronchiectasis. CONCLUSION Our preliminary results indicate that the HASTE sequence provides a practical means for breath-hold MR imaging of lung parenchyma.
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Affiliation(s)
- H Hatabu
- Department of Radiology and Medicine, Beth Israel Deaconess Medical Center and Harvard Medical School, Boston, MA 02215, USA.
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Abstract
The impact of fast MR techniques developed for MR imaging of the lung will soon be recognized as equivalent to the high-resolution technique in chest CT imaging. In this article, the difficulties in MR imaging posed by lung morphology and its physiological motion are briefly introduced. Then, fast MR imaging techniques to overcome the problems of lung imaging and recent applications of the fast MR techniques including pulmonary perfusion and ventilation imaging are discussed. Fast MR imaging opens a new exciting window to multi-functional MR imaging of the lung. We believe that fast MR functional imaging will play an important role in the assessment of pulmonary function and disease process.
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Affiliation(s)
- H Hatabu
- Department of Radiology, Beth Israel Deaconess Medical Center and Harvard Medical School, Boston, MA 02215, USA.
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Abstract
This article reviews fast magnetic resonance (MR) techniques currently used for body imaging. Improvements in gradient performance have made very short repetition and echo times on clinical scanners feasible, thus enabling subsecond image acquisition. The article provides a fundamental overview of the technical aspects from the concept of k-space and k-space segmentation technique, fast MR imaging techniques including fast spin echo, fast gradient echo with or without magnetization preparation to echo planar and hybrid techniques. The article also addresses the use of different fat suppression techniques in MR imaging of the body and improvements in coil technology to obtain faster images and higher signal-to-noise.
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Affiliation(s)
- Q Chen
- Department of Radiology, Beth Israel Deaconess Medical Center and Harvard Medical School, Boston, MA 02215, USA
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Affiliation(s)
- D L Levin
- Department of Radiology, Beth Israel Deaconess Medical Center, Boston, MA 02215, USA
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Hatabu H, Wielopolski PA, Tadamura E. An attempt of pulmonary perfusion imaging utilizing ultrashort echo time turbo FLASH sequence with signal targeting and alternating radio-frequency (STAR). Eur J Radiol 1999; 29:160-3. [PMID: 10374664 DOI: 10.1016/s0720-048x(98)00168-5] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
Affiliation(s)
- H Hatabu
- Department of Radiology, Beth Israel Deaconess Medical Center, Boston, MA 02215, USA.
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Abstract
The current work is a continuation of a new MRI technique that was proposed for the non-invasive assessment of regional lung ventilation using inhaled molecular oxygen as a T1 contrast agent. Several improvements of this technique are described in this work. The signal-to-noise ratio in the ventilation-scan images was optimized using a centrically reordered single-shot RARE sequence with a short effective echo time and short inter-echo spacing. The contrast-to-noise ratio was improved using an optimized inversion delay time. The optimized MR-ventilation-scan was successfully performed in healthy volunteers and in an animal model with airway obstruction. The experimental results demonstrate the feasibility and clinical potential of the MR ventilation imaging technique for assessment of regional pulmonary function.
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Affiliation(s)
- Q Chen
- Department of Radiology, Beth Israel Deaconess Medical Center, Boston, MA 02215, USA.
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Kataoka ML, Togashi K, Konishi I, Hatabu H, Morikawa K, Kojima N, Kuroda H, Fujimoto R, Kataoka N, Konishi J. MRI of adenomyotic cyst of the uterus. J Comput Assist Tomogr 1998; 22:555-9. [PMID: 9676445 DOI: 10.1097/00004728-199807000-00010] [Citation(s) in RCA: 46] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
The radiologic and pathologic features of three cases of adenomyotic cysts are presented. Two cases were subserosal and one was intramyometrial. All three cases had cystic spaces filled with hyperintense fluid on T1-weighted images, which were surrounded by hypointense tissue on T2-weighted images.
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Affiliation(s)
- M L Kataoka
- Department of Radiology, Faculty of Medicine, Kyoto University, Japan
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Kundel HL, Gefter W, Aronchick J, Miller W, Hatabu H, Whitfill CH, Miller W. Accuracy of bedside chest hard-copy screen-film versus hard- and soft-copy computed radiographs in a medical intensive care unit: receiver operating characteristic analysis. Radiology 1997; 205:859-63. [PMID: 9393548 DOI: 10.1148/radiology.205.3.9393548] [Citation(s) in RCA: 23] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
PURPOSE To compare the clinical diagnostic accuracy of hard-copy readings of screen-film bedside chest radiographs and both hard- and soft-copy readings of bedside chest computed radiographs obtained in a medical intensive care unit. MATERIALS AND METHODS Two samples of 95 cases were assembled from chest images obtained in 541 patients with either screen-film radiography or computed radiography. The cases were stratified according to the clinical problem for which the examination was ordered; the corresponding diagnosis was verified by a panel of two or three radiologists. Four radiologists blindly read the hard-copy images obtained with screen-film or computed radiography. Six months later, the radiologists read the computed radiographs by using an 8-bit, 1,684 x 2,048-pixel display. The data were analyzed by using multireader-multicase receiver operating characteristic (ROC) analysis of variance. RESULTS No statistically significant differences in the area under the ROC curve were found between any of the methods. CONCLUSION The results provide some justification for using bedside chest computed radiography and for reading soft-copy images from a high-quality display.
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Affiliation(s)
- H L Kundel
- Department of Radiology, Pendergrass Diagnostic Research Laboratory, University of Pennsylvania Medical School, Philadelphia 19104-6086, USA
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Abstract
PURPOSE Granulosa cell tumor is a rare but unique ovarian tumor that frequently produces estrogen. The purpose of this study is to identify the MR features and clinical manifestations useful in diagnosing this tumor. METHOD Clinical presentations and MR findings from five patients with pathologically proven granulosa cell tumor were reviewed. RESULTS All five granulosa cell tumors were hormonally active. Initial clinical presentations were abnormal genital bleeding suspicious of endometrial carcinoma in two patients and adnexal masses in three patients. All tumors were solid masses with variable amount of cystic components. Hemorrhage within the tumor was identified in three patients. Enlargement of the uterus was observed in four patients. Endometrial thickening was also identified in four patients. CONCLUSION Recognition of these characteristics may help to differentiate granulosa cell tumor from other ovarian tumors.
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Affiliation(s)
- K Morikawa
- Department of Radiology and Nuclear Medicine, Faculty of Medicine, Kyoto University, Japan
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Abstract
Recent advances in MR pulmonary angiography and MR perfusion imaging are reviewed, focusing on two principal areas of technical development: (1) the availability of MR scanners equipped with enhanced gradient systems; and (2) new trends in MR angiography using gadolinium contrast agents or labeling of blood with an inversion recovery radiofrequency pulse in place of the more traditional methods using naturally flowing spins as the source of intravascular signal. These recent developments in MR have significant potential for clinical imaging of the pulmonary vasculature, particularly for the diagnosis of pulmonary embolism, and are now opening windows to functional MR imaging of the lung.
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Affiliation(s)
- H Hatabu
- Department of Radiology and Nuclear Medicine, Kyoto University Hospital, Sakyo-Ku, Japan
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Abstract
Ovarian fibromas are solid neoplasms that are difficult to differentiate radiologically from uterine leiomyomas. In this report, we describe the contrast-enhanced magnetic resonance imaging features of a 13-cm-diameter solid pelvic mass that allowed us to make the prospective diagnosis of ovarian fibroma.
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Affiliation(s)
- R K Schwartz
- Department of Radiology, Beth Israel Hospital, 330 Brookline Avenue, Boston, MA 02215, USA
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Abstract
The effect of the oxygen inhalation on relaxation times was evaluated in various tissues, including the myocardium, liver, spleen, skeletal muscle, subcutaneous fat, bone marrow, and arterial blood, with a [1H]MR system. Statistically significant decrease of T1 relaxation times was observed in the myocardium, spleen, and arterial blood after inhalation of 100% oxygen, whereas no significant change was observed in liver, skeletal muscle, subcutaneous fat, or bone marrow. The T2 relaxation time of these tissues did not differ significantly between before and after inhalation of the oxygen. These results indicate that [1H]MRI can be used to evaluate changes with oxygen inhalation and that the effect of the oxygen inhalation on T1 relaxation time is different among various tissues.
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Affiliation(s)
- E Tadamura
- Department of Radiology, Beth Israel Hospital, Boston, Massachusetts, USA
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