Imaging of the Pediatric Abdomen and Pelvis
P re f a c e
Jonathan R. Dillman, MD
Ethan A. Smith, MD
Editors
developed pulse sequences have allowed for decreased imaging times with a resultant reduced need for sedation and general anesthesia. We are also particularly excited about the increasing availability and use of 3-Tesla MRI scanners for imaging of the pediatric abdomen and pelvis. In our practice, we now commonly prefer higher field strength imaging in younger children (including neonates and infants) as abdominopelvic image quality seems overall superior to imaging performed at lower field strengths. Numerous examples of MRI of the abdomen and pelvis at 3-Tesla are presented in this issue. One such instance where 3-Tesla high-spatial-resolution MRI is critical is in the assessment of perianal and perineal Crohn disease, as shown in the article, “Magnetic resonance imaging of Perianal and Perineal Crohn Disease in Children and Adolescents.” The present issue is a collection of twelve unique review articles covering a wide range of pediatric abdominopelvic MRI topics. These articles are authored by well-respected, national and international leaders in the field of Pediatric Radiology. It is our hope that readers will find the image-rich material provided in these articles to be informative and relevant to daily clinical practice. Briefly, articles in the present issue include the following: 1. In the article entitled, “Magnetic Resonance Imaging of the Pediatric Liver: Benign and Malignant Masses,” key imaging findings of
Magn Reson Imaging Clin N Am 21 (2013) xv–xvii http://dx.doi.org/10.1016/j.mric.2013.07.009 1064-9689/13/$ – see front matter Ó 2013 Published by Elsevier Inc.
mri.theclinics.com
It has been our pleasure to serve as guest editors for the current issue of Magnetic Resonance Imaging Clinics of North America entitled, “Imaging of the Pediatric Abdomen and Pelvis.” We are thrilled to present numerous contemporary review articles presenting the use of state-of-the-art abdominopelvic MRI techniques in children and adolescents. In our pediatric radiology practice, the use of magnetic resonance imaging (MRI) for the evaluation of abnormalities of the abdomen and pelvis continues to steadily increase. In recent years, many new MRI applications have entered routine pediatric clinical practice. In fact, in several instances at many institutions, MRI has supplanted the previous imaging standard (eg, MR enterography replacing either computed tomography enterography or fluoroscopic studies for evaluation of inflammatory bowel disease). Increasing utilization of abdominopelvic MRI in the pediatric population is likely due to several factors. Of course, a major driver of increasing use is the fact that MRI does not require ionizing radiation, thus avoiding any potential harmful adverse effects. However, there are other reasons to explain this increased utilization. Relatively recent hardware and software advances have led to much improved image quality due to increased signal-to-noise ratio, contrast-to-noise ratio, and spatial resolution. Taken together, these advances have allowed for substantial improvements in image quality when imaging the pediatric abdomen and pelvis. Parallel imaging techniques and newly
xvi
Preface
2.
3.
4.
5.
6.
7.
common benign and malignant liver masses are presented. The authors also devote substantial attention to the use of hepatocytespecific contrast material for focal liver lesion characterization (an “off-label” practice in the pediatric population). In the article entitled, “Magnetic Resonance Imaging of the Pediatric Liver: Imaging of Steatosis, Iron Deposition, and Fibrosis,” established and cutting-edge techniques for imaging diffuse liver diseases using both qualitative and quantitative approaches are described. The authors detail available noninvasive MRI-based methods for evaluation of hepatic fat, iron deposition, and fibrosis and discuss advantages and disadvantages of these different techniques. In the article entitled, “Magnetic Resonance Imaging of the Pediatric Pancreaticobiliary System,” the use of magnetic resonance cholangiopancreatography (MRCP) is extensively reviewed. The authors present MRCP techniques, including advantages and disadvantages, and indications for imaging, as well as present the imaging appearances of numerous common and uncommon conditions affecting the pancreaticobiliary system. In the article entitled, “Magnetic Resonance Imaging of the Pediatric Kidney: Benign and Malignant Masses,” both the clinical and imaging features of benign and malignant renal masses that occur in children and adolescents are presented. Imaging technique is also reviewed. In the article entitled, “Magnetic Resonance Urography in Evaluation of Duplicated Renal Collecting Systems,” the authors discuss appropriate terminology for duplicated upper urinary tracts as well as pertinent embryology. The various clinical presentations and imaging appearances of duplicated renal collecting systems are also presented in detail. In the article entitled, “Magnetic Resonance Enterography: IBD and Beyond,” a comprehensive review of MRI of the bowel in children is presented. Variations on the basic MR enterography protocol are discussed, and the advantages and disadvantages of each are described. The article also includes a review of inflammatory bowel disease classification and image interpretation and concludes with a discussion of potential applications of MR enterography beyond imaging of inflammatory bowel disease. In the article entitled, “Magnetic Resonance Imaging of Pediatric Pelvic Masses,” the authors provide a broad review of both benign
8.
9.
10.
11.
12.
and malignant pediatric pelvic masses and stress the advantages of MRI for initial diagnosis, staging, and imaging surveillance. MR imaging characteristics of specific masses are reviewed and imaging technique is discussed. In the article entitled, “Mu¨llerian Duct and Related Anomalies in Children and Adolescents,” common and uncommon developmental anomalies of the uterus and vagina are described. Relevant embryology, classification, and imaging findings are presented in a systematic manner. In the article entitled, “Magnetic Resonance Imaging of Anorectal Malformations,” the increasing roles of MRI in the evaluation of anorectal and other complex pelvic malformations prenatally and postnatally prior to definitive surgical repair are presented in detail. Expected and unexpected postoperative MRI findings are also described. In the article entitled, “Magnetic Resonance Imaging of Perianal and Perineal Crohn Disease in Children and Adolescents,” perineal and perianal imaging findings of Crohn disease in the pediatric population are presented, including fistulous disease, abscesses, and skin manifestations. Perianal anatomy, classification of perianal Crohn disease lesions, and MRI technique are also reviewed. In the article entitled, “Advanced Techniques in Pediatric Abdominopelvic Oncologic Magnetic Resonance Imaging,” the author reviews the role of MRI in the management of pediatric cancer patients, including a review oncologic MR imaging protocol issues. The article also presents cutting-edge MR imaging techniques, including diffusion-weighted imaging, whole-body MRI, dynamic contrast-enhanced MRI, and positron emission tomography-MRI. In the article entitled, “Magnetic Resonance Angiography of the Pediatric Abdomen and Pelvis: Techniques and Imaging Findings,” the authors provide a comprehensive review of the various noncontrast and contrastenhanced techniques for vascular MR imaging. The second half of the article focuses on common and uncommon vascular anatomic variants and pathologic conditions that occur in the pediatric population.
We would like to sincerely thank all of the authors, who spent countless hours contributing to this effort. We would also like to acknowledge Pamela Hetherington, who shepherded both the authors and the editors through the preparation of this issue. It is our hope that readers of these works learn as much about state-of-the-art
Preface pediatric abdominopelvic MRI as we have while assembling this issue! Jonathan R. Dillman, MD Section of Pediatric Radiology Department of Radiology University of Michigan Health System C.S. Mott Children’s Hospital Ann Arbor, MI 48109, USA
Ethan A. Smith, MD Section of Pediatric Radiology Department of Radiology University of Michigan Health System C.S. Mott Children’s Hospital Ann Arbor, MI 48109, USA E-mail addresses: [email protected] (J.R. Dillman) [email protected] (E.A. Smith)
xvii
P re f a c e
Jonathan R. Dillman, MD
Ethan A. Smith, MD
Editors
developed pulse sequences have allowed for decreased imaging times with a resultant reduced need for sedation and general anesthesia. We are also particularly excited about the increasing availability and use of 3-Tesla MRI scanners for imaging of the pediatric abdomen and pelvis. In our practice, we now commonly prefer higher field strength imaging in younger children (including neonates and infants) as abdominopelvic image quality seems overall superior to imaging performed at lower field strengths. Numerous examples of MRI of the abdomen and pelvis at 3-Tesla are presented in this issue. One such instance where 3-Tesla high-spatial-resolution MRI is critical is in the assessment of perianal and perineal Crohn disease, as shown in the article, “Magnetic resonance imaging of Perianal and Perineal Crohn Disease in Children and Adolescents.” The present issue is a collection of twelve unique review articles covering a wide range of pediatric abdominopelvic MRI topics. These articles are authored by well-respected, national and international leaders in the field of Pediatric Radiology. It is our hope that readers will find the image-rich material provided in these articles to be informative and relevant to daily clinical practice. Briefly, articles in the present issue include the following: 1. In the article entitled, “Magnetic Resonance Imaging of the Pediatric Liver: Benign and Malignant Masses,” key imaging findings of
Magn Reson Imaging Clin N Am 21 (2013) xv–xvii http://dx.doi.org/10.1016/j.mric.2013.07.009 1064-9689/13/$ – see front matter Ó 2013 Published by Elsevier Inc.
mri.theclinics.com
It has been our pleasure to serve as guest editors for the current issue of Magnetic Resonance Imaging Clinics of North America entitled, “Imaging of the Pediatric Abdomen and Pelvis.” We are thrilled to present numerous contemporary review articles presenting the use of state-of-the-art abdominopelvic MRI techniques in children and adolescents. In our pediatric radiology practice, the use of magnetic resonance imaging (MRI) for the evaluation of abnormalities of the abdomen and pelvis continues to steadily increase. In recent years, many new MRI applications have entered routine pediatric clinical practice. In fact, in several instances at many institutions, MRI has supplanted the previous imaging standard (eg, MR enterography replacing either computed tomography enterography or fluoroscopic studies for evaluation of inflammatory bowel disease). Increasing utilization of abdominopelvic MRI in the pediatric population is likely due to several factors. Of course, a major driver of increasing use is the fact that MRI does not require ionizing radiation, thus avoiding any potential harmful adverse effects. However, there are other reasons to explain this increased utilization. Relatively recent hardware and software advances have led to much improved image quality due to increased signal-to-noise ratio, contrast-to-noise ratio, and spatial resolution. Taken together, these advances have allowed for substantial improvements in image quality when imaging the pediatric abdomen and pelvis. Parallel imaging techniques and newly
xvi
Preface
2.
3.
4.
5.
6.
7.
common benign and malignant liver masses are presented. The authors also devote substantial attention to the use of hepatocytespecific contrast material for focal liver lesion characterization (an “off-label” practice in the pediatric population). In the article entitled, “Magnetic Resonance Imaging of the Pediatric Liver: Imaging of Steatosis, Iron Deposition, and Fibrosis,” established and cutting-edge techniques for imaging diffuse liver diseases using both qualitative and quantitative approaches are described. The authors detail available noninvasive MRI-based methods for evaluation of hepatic fat, iron deposition, and fibrosis and discuss advantages and disadvantages of these different techniques. In the article entitled, “Magnetic Resonance Imaging of the Pediatric Pancreaticobiliary System,” the use of magnetic resonance cholangiopancreatography (MRCP) is extensively reviewed. The authors present MRCP techniques, including advantages and disadvantages, and indications for imaging, as well as present the imaging appearances of numerous common and uncommon conditions affecting the pancreaticobiliary system. In the article entitled, “Magnetic Resonance Imaging of the Pediatric Kidney: Benign and Malignant Masses,” both the clinical and imaging features of benign and malignant renal masses that occur in children and adolescents are presented. Imaging technique is also reviewed. In the article entitled, “Magnetic Resonance Urography in Evaluation of Duplicated Renal Collecting Systems,” the authors discuss appropriate terminology for duplicated upper urinary tracts as well as pertinent embryology. The various clinical presentations and imaging appearances of duplicated renal collecting systems are also presented in detail. In the article entitled, “Magnetic Resonance Enterography: IBD and Beyond,” a comprehensive review of MRI of the bowel in children is presented. Variations on the basic MR enterography protocol are discussed, and the advantages and disadvantages of each are described. The article also includes a review of inflammatory bowel disease classification and image interpretation and concludes with a discussion of potential applications of MR enterography beyond imaging of inflammatory bowel disease. In the article entitled, “Magnetic Resonance Imaging of Pediatric Pelvic Masses,” the authors provide a broad review of both benign
8.
9.
10.
11.
12.
and malignant pediatric pelvic masses and stress the advantages of MRI for initial diagnosis, staging, and imaging surveillance. MR imaging characteristics of specific masses are reviewed and imaging technique is discussed. In the article entitled, “Mu¨llerian Duct and Related Anomalies in Children and Adolescents,” common and uncommon developmental anomalies of the uterus and vagina are described. Relevant embryology, classification, and imaging findings are presented in a systematic manner. In the article entitled, “Magnetic Resonance Imaging of Anorectal Malformations,” the increasing roles of MRI in the evaluation of anorectal and other complex pelvic malformations prenatally and postnatally prior to definitive surgical repair are presented in detail. Expected and unexpected postoperative MRI findings are also described. In the article entitled, “Magnetic Resonance Imaging of Perianal and Perineal Crohn Disease in Children and Adolescents,” perineal and perianal imaging findings of Crohn disease in the pediatric population are presented, including fistulous disease, abscesses, and skin manifestations. Perianal anatomy, classification of perianal Crohn disease lesions, and MRI technique are also reviewed. In the article entitled, “Advanced Techniques in Pediatric Abdominopelvic Oncologic Magnetic Resonance Imaging,” the author reviews the role of MRI in the management of pediatric cancer patients, including a review oncologic MR imaging protocol issues. The article also presents cutting-edge MR imaging techniques, including diffusion-weighted imaging, whole-body MRI, dynamic contrast-enhanced MRI, and positron emission tomography-MRI. In the article entitled, “Magnetic Resonance Angiography of the Pediatric Abdomen and Pelvis: Techniques and Imaging Findings,” the authors provide a comprehensive review of the various noncontrast and contrastenhanced techniques for vascular MR imaging. The second half of the article focuses on common and uncommon vascular anatomic variants and pathologic conditions that occur in the pediatric population.
We would like to sincerely thank all of the authors, who spent countless hours contributing to this effort. We would also like to acknowledge Pamela Hetherington, who shepherded both the authors and the editors through the preparation of this issue. It is our hope that readers of these works learn as much about state-of-the-art
Preface pediatric abdominopelvic MRI as we have while assembling this issue! Jonathan R. Dillman, MD Section of Pediatric Radiology Department of Radiology University of Michigan Health System C.S. Mott Children’s Hospital Ann Arbor, MI 48109, USA
Ethan A. Smith, MD Section of Pediatric Radiology Department of Radiology University of Michigan Health System C.S. Mott Children’s Hospital Ann Arbor, MI 48109, USA E-mail addresses: [email protected] (J.R. Dillman) [email protected] (E.A. Smith)
xvii
