Publications by authors named "Mary-Louise C Greer"

39 Publications

Strategies to perform magnetic resonance imaging in infants and young children without sedation.

Pediatr Radiol 2021 Apr 8. Epub 2021 Apr 8.

Department of Radiology, Massachusetts General Hospital, 55 Fruit St., Boston, MA, 02114, USA.

Given the increasing use of MRI in the pediatric population, the need for sedation in MRI performed in young children is a topic of growing importance. Although sedation is generally tolerated well by children, the financial and operational impacts of anesthesia on MRI workflow, as well as potential adverse effects of anesthetic medications, highlight the need to perform MRI in children without sedation whenever possible. This review focuses on current techniques to facilitate non-sedation MRI in children, including exam preparation with MRI simulation; asleep but not sedated techniques; awake and relaxed techniques using certified child life specialists, animal-assisted therapy, a child-friendly environment and in-scan entertainment; and non-sedated MRI protocol modifications such as shorter scan time, prioritizing sequences, reducing motion artifact, noise reduction, limiting use of gadolinium, employing an open MRI and modifying protocols.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1007/s00247-021-05062-3DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8027290PMC
April 2021

Screening of cancer predisposition syndromes.

Pediatr Radiol 2021 Apr 1. Epub 2021 Apr 1.

Department of Diagnostic Imaging, The Hospital for Sick Children, 555 University Ave., Toronto, ON, M5G 1X8, Canada.

Pediatric patients with cancer predisposition syndromes are at increased risk of developing malignancies compared with their age-matched peers, necessitating regular surveillance. Screening protocols differ among syndromes and are composed of a number of elements, imaging being one. Surveillance can be initiated in infants, children and adolescents with a tumor known or suspected of being related to a cancer predisposition syndrome or where genetic testing identifies a germline pathogenic gene variant in an asymptomatic child. Pre-symptomatic detection of malignant neoplasms offers potential to improve treatment options and survival outcomes, but the benefits and risks of screening need to be weighed, particularly with variable penetrance in many cancer predisposition syndromes. In this review we discuss the benefits and risks of surveillance imaging and the importance of integrating imaging and non-imaging screening elements. We explore the principles of surveillance imaging with particular reference to whole-body MRI, considering the strategies to minimize false-negative and manage false-positive whole-body MRI results, the value of standardized nomenclature when reporting risk stratification to better guide patient management, and the need for timely communication of results to allay anxiety. Cancer predisposition syndrome screening is a multimodality, multidisciplinary and longitudinal process, so developing formalized frameworks for surveillance imaging programs should enhance diagnostic performance while improving the patient experience.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1007/s00247-021-05023-wDOI Listing
April 2021

Magnetic resonance imaging quality control, quality assurance and quality improvement.

Pediatr Radiol 2021 Mar 27. Epub 2021 Mar 27.

Department of Radiology, Massachusetts General Hospital, Boston, MA, USA.

Quality in MR imaging is a comprehensive process that encompasses scanner performance, clinical processes for efficient scanning and reporting, as well as data-driven improvement involving measurement of key performance indicators. In this paper, the authors review this entire process. This article provides a framework for establishing a successful MR quality program. The collective experiences of the authors across a spectrum of pediatric hospitals is summarized here.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1007/s00247-021-05043-6DOI Listing
March 2021

Magnetic Resonance Liver Lymphangiography for Investigation and Transhepatic Lymphatic Embolization for the Treatment of Protein-Losing Enteropathy.

J Vasc Interv Radiol 2021 02 29;32(2):327-329.e2. Epub 2020 Nov 29.

Division of Image Guided Therapy, Department of Diagnostic Imaging, The Hospital for Sick Children, Toronto, ON, Canada; Medical Imaging Department, University of Toronto, ON, Canada.

View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.jvir.2020.10.012DOI Listing
February 2021

Clinical-stage Approaches for Imaging Chronic Inflammation and Fibrosis in Crohn's Disease.

Inflamm Bowel Dis 2020 Sep;26(10):1509-1523

Department of Diagnostic Imaging, Kingston Health Sciences Centre, Queen's University, Kingston, Ontario, Canada.

The number of imaging-based indices developed for inflammatory bowel disease as research tools, objectively measuring ileocolonic and perianal activity and treatment response, has expanded in the past 2 decades. Created primarily to assess Crohn's disease (CD), there is increasing adoption of these indices into the clinical realm to guide patient care. This translation has been facilitated by validation in adult and pediatric populations, prompted by simplification of score calculations needed for practical application outside the research environment. The majority of these indices utilize magnetic resonance imaging (MRI), specifically MR enterography (MRE) and pelvic MRI, and more recently ultrasound. This review explores validated indices by modality, anatomic site and indication, including for documentation of the presence and extent of CD, disease progression, complications, and treatment response, highlighting those in clinical use or with the potential to be. As well, it details index imaging features used to quantify chronic inflammatory activity, severity, and to lesser extent fibrosis, in addition to their reference standards and any modifications. Validation in the pediatric population of indices primarily developed in adult cohorts such as the Magnetic Resonance Index of Activity (MaRIA), the Simplified Magnetic Resonance Index of Activity (MARIAs), and the MRE global score (MEGS), together with newly developed pediatric-specific indices, are discussed. Indices that may be predictive of disease course and investigational techniques with the potential to provide future imaging biomarkers, such as multiparametric MRI, are also briefly considered.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1093/ibd/izaa218DOI Listing
September 2020

Whole-body MRI versus an FDG-PET/CT-based reference standard for staging of paediatric Hodgkin lymphoma: a prospective multicentre study.

Eur Radiol 2021 Mar 3;31(3):1494-1504. Epub 2020 Sep 3.

Department of Radiology and Nuclear Medicine, University Medical Center Utrecht/Wilhelmina Children's Hospital, Utrecht University, Heidelberglaan 100, 3584 CX, Utrecht, The Netherlands.

Objectives: To assess the concordance of whole-body MRI (WB-MRI) and an FDG-PET/CT-based reference standard for the initial staging in children with Hodgkin lymphoma (HL) METHODS: Children with newly diagnosed HL were included in this prospective, multicentre, international study and underwent WB-MRI and FDG-PET/CT at staging. Two radiologists and a nuclear medicine physician independently evaluated all images. Discrepancies between WB-MRI and FDG-PET/CT were assessed by an expert panel. All FDG-PET/CT errors were corrected to derive the FDG-PET/CT-based reference standard. The expert panel corrected all reader errors in the WB-MRI DWI dataset to form the intrinsic MRI data. Inter-observer agreement for WB-MRI DWI was calculated using overall agreement, specific agreements and kappa statistics. Concordance for correct classification of all disease sites and disease stage between WB-MRI (without DWI, with DWI and intrinsic WB-MRI DWI) and the reference standard was calculated as primary outcome. Secondary outcomes included positive predictive value, negative predictive value and kappa statistics. Clustering within patients was accounted for using a mixed-effect logistic regression model with random intercepts and a multilevel kappa analysis.

Results: Sixty-eight children were included. Inter-observer agreement between WB-MRI DWI readers was good for disease stage (κ = 0.74). WB-MRI DWI agreed with the FDG-PET/CT-based reference standard for determining disease stage in 96% of the patients versus 88% for WB-MRI without DWI. Agreement between WB-MRI DWI and the reference standard was excellent for both nodal (98%) and extra-nodal (100%) staging.

Conclusions: WB-MRI DWI showed excellent agreement with the FDG-PET/CT-based reference standard. The addition of DWI to the WB-MRI protocol improved the staging agreement.

Key Points: • This study showed excellent agreement between WB-MRI DWI and an FDG-PET/CT-based reference standard for staging paediatric HL. • Diffusion-weighted imaging is a useful addition to WB-MRI in staging paediatric HL. • Inter-observer agreement for WB-MRI DWI was good for both nodal and extra-nodal staging and determining disease stage.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1007/s00330-020-07182-0DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7880958PMC
March 2021

Whole-Body MRI Surveillance of Cancer Predisposition Syndromes: Current Best Practice Guidelines for Use, Performance, and Interpretation.

AJR Am J Roentgenol 2020 10 18;215(4):1002-1011. Epub 2020 Aug 18.

Department of Radiology, Massachusetts General Hospital, Harvard Medical School, 55 Fruit St, Ellison 237, Boston, MA 02114-2696.

Whole-body MRI is a valuable tool in the surveillance of cancer predisposition syndromes (CPSs). Because it allows wide-FOV imaging without ionizing radiation, whole-body MRI is ideal in pediatric patients, enabling efficient assessment of different organ systems for multifocal disease. This article summarizes the use of whole-body MRI in pediatric patients with CPSs for earlier detection of malignancy, provides evidence where available, and offers guidance where lacking because of the rarity of CPSs. Protocol modifications and technique performance in specific CPSs are also considered. Whole-body MRI is the preferred imaging modality for surveillance of pediatric patients with CPSs, and the growing literature supports its importance in presymptomatic cancer detection.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.2214/AJR.19.22399DOI Listing
October 2020

Magnetic Resonance Lymphangiography.

Radiol Clin North Am 2020 Jul 6;58(4):693-706. Epub 2020 May 6.

Department of Diagnostic Imaging, The Hospital for Sick Children and Medical Imaging, University of Toronto, 555 University Avenue, Toronto, Ontario M5G 1X8, Canada; Division of Cardiology, Department of Paediatrics, The Hospital for Sick Children, University of Toronto, 555 University Avenue, Toronto, Ontario M5G 1X8, Canada.

Dynamic contrast-enhanced magnetic resonance lymphangiography is a novel technique to image central conducting lymphatics. It is performed by injecting contrast into groin lymph nodes and following passage of contrast through lymphatic system using T1-weighted MR images. Currently, it has been successfully applied to image and plan treatment of thoracic duct pathologies, lymphatic leaks, and other lymphatic abnormalities such as plastic bronchitis. It is useful in the assessment of chylothorax and chyloperitoneum. Its role in other areas such as intestinal lymphangiectasia and a variety of lymphatic anomalies is likely to increase.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.rcl.2020.02.002DOI Listing
July 2020

Recommendations for Long-Term Follow-up of Adults with Heritable Retinoblastoma.

Ophthalmology 2020 11 15;127(11):1549-1557. Epub 2020 May 15.

Memorial Sloan Kettering Cancer Center, New York, New York; Weill Cornell Medical College, New York, New York.

Purpose: To generate recommendations for long-term follow-up of adult survivors of heritable retinoblastoma.

Design: We convened a meeting of providers from retinoblastoma centers around the world to review the state of the science and to evaluate the published evidence.

Participants: Retinoblastoma is a rare childhood cancer of the retina. Approximately 40% of retinoblastoma cases are heritable, resulting from a germline mutation in RB1. Dramatic improvements in treatment and supportive care have resulted in a growing adult survivor population. However, survivors of heritable retinoblastoma have a significantly increased risk of subsequent malignant neoplasms, particularly bone and soft tissue sarcomas, uterine leiomyosarcoma, melanomas, and radiotherapy-related central nervous system tumors, which are associated with excess morbidity and mortality. Despite these risks, no surveillance recommendations for this population currently are in place, and surveillance practices vary widely by center.

Methods: Following the Institute of Medicine procedure for clinical practice guideline development, a PubMed, EMBASE, and Web of Science search was performed, resulting in 139 articles; after abstract and full-text review, 37 articles underwent detailed data abstraction to quantify risk and evidence regarding surveillance, if available. During an in-person meeting, evidence was presented and discussed, resulting in consensus recommendations.

Main Outcome Measures: Diagnosis and mortality from subsequent neoplasm.

Results: Although evidence for risk of subsequent neoplasm, especially sarcoma and melanoma, was significant, evidence supporting routine testing of asymptomatic survivors was not identified. Skin examination for melanoma and prompt evaluation of signs and symptoms of head and neck disease were determined to be prudent.

Conclusions: This review of the literature confirmed some of the common second cancers in retinoblastoma survivors but found little evidence for a benefit from currently available surveillance for these malignancies. Future research should incorporate international partners, patients, and family members.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.ophtha.2020.05.024DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7606265PMC
November 2020

Congenital hypothyroidism, cardiac defects, and pancreatic agenesis in an infant with GATA6 mutation.

Am J Med Genet A 2020 06 24;182(6):1496-1499. Epub 2020 Mar 24.

Division of Clinical and Metabolic Genetics, The Hospital for Sickkids, University of Toronto, Toronto, Ontario, Canada.

GATA6 pathogenic variants primarily manifest a phenotype with pancreatic agenesis and cardiac malformations. However, additional congenital malformations affecting the biliary system, congenital diaphragmatic hernia and developmental delay have been reported. We report a newborn, prenatally diagnosed with truncus arteriosus and intrauterine growth restriction, who was postnatally found to have pancreatic agenesis associated with neonatal diabetes and hepatobiliary abnormalities. Whole exome sequencing identified a de novo, heterozygous mutation in the GATA6 gene (c.1366C>T; p.Arg456Cys). Further investigations revealed abnormalities not previously associated with GATA6 mutation, including unilateral thyroid lobe agenesis associated with congenital hypothyroidism, absent gall bladder, possible adrenal insufficiency, thrombocytopenia, and neonatal stroke.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1002/ajmg.a.61569DOI Listing
June 2020

Reply to "A Multidisciplinary Response to the Canadian Association of Radiologists' Point-of-Care Ultrasound Position Statement".

Can Assoc Radiol J 2020 05 13;71(2):138-139. Epub 2020 Feb 13.

Department of Diagnostic Imaging, The Hospital for Sick Children, University of Toronto, Toronto, Ontario, Canada.

View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1177/0846537119899277DOI Listing
May 2020

Invited Commentary: Reducing Sedation and Anesthesia in Pediatric Patients at MRI.

Radiographics 2020 Mar-Apr;40(2):503-504. Epub 2020 Feb 7.

Department of Radiology, Stanford University, Stanford, California.

View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1148/rg.2020190211DOI Listing
June 2020

Magnetic Resonance Cholangiopancreatography Severity Predicts Disease Outcomes in Pediatric Primary Sclerosing Cholangitis: A Reliability and Validity Study.

Hepatol Commun 2020 Feb 6;4(2):208-218. Epub 2019 Dec 6.

Department of Diagnostic Imaging The Hospital for Sick Children Toronto Canada.

Magnetic resonance cholangiopancreatography (MRCP) has not been assessed as a surrogate biomarker in pediatrics. We aimed to determine the inter-rater reliability, prognostic utility, and construct validity of the modified Majoie endoscopic retrograde cholangiopancreatography classification applied to MRCP in a pediatric primary sclerosing cholangitis (PSC) cohort. This single-center, retrospective, cohort study included children with PSC undergoing diagnostic MRCP between 2008 and 2016. Six variations of the Majoie classification were examined: 1) intrahepatic duct (IHD) score, 2) extrahepatic duct (EHD) score (representing the worst intrahepatic and extrahepatic regions, respectively), 3) sum IHD-EHD score, 4) average IHD score, 5) average EHD score, and 6) sum average IHD-EHD score. Inter-rater reliability was assessed using weighted kappas and intraclass correlation coefficients (ICCs). Ability to predict time to PSC-related complications (ascites, esophageal varices, variceal bleed, liver transplant [LT], or cholangiocarcinoma) (primary outcome) and LT (secondary outcome) was assessed with Harrell's concordance statistic (c-statistic) and univariate/multivariable survival analysis. Construct validity was further assessed with Spearman correlations. Forty-five children were included (67% boys; median, 13.6 years). The inter-rater reliability of MRCP scores was substantial to excellent (kappas/ICCs, 0.78-0.82). The sum IHD-EHD score had the best predictive ability for time to PSC complication and LT (c-statistic, 0.80 and SE, 0.06; and c-statistic, 0.97 and SE, 0.01, respectively). Higher MRCP scores were independently associated with a higher rate of PSC-related complications, even after adjusting for the PSC Mayo risk score (hazard ratio, 1.74; 95% confidence interval, 1.14-2.). MRCP sum scores correlated significantly with METAVIR fibrosis stage, total bilirubin, and platelets ( = 0.42,  = 0.33,  = -0.31, respectively;  < 0.05). An MRCP score incorporating the worst affected intrahepatic and extrahepatic regions is reliable and predicts meaningful outcomes in pediatric PSC. Next steps include prospective validation and responsiveness assessment.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1002/hep4.1454DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6996389PMC
February 2020

Magnetic Resonance in Crohn's Disease: Diagnosis, Disease Burden, and Classification.

Magn Reson Imaging Clin N Am 2020 Feb;28(1):31-44

Department of Radiology, Mayo Clinic, 200 First Street Southwest, Rochester, MN 55905, USA. Electronic address:

Magnetic resonance enterography (MRE) is an established test in patients with Crohn because of its ability to display transmural enteric inflammation and treatment response throughout the gastrointestinal tract without the very low potential risk of ionizing radiation. This article discusses how and when to diagnose Crohn disease with MRE (including discussion of the main differential diagnosis), how to describe the burden of enteric inflammation and its complications, and how to accurately classify disease based on interdisciplinary consensus. In addition, brief overviews of expected future MRE developments and alternative imaging modalities are also discussed.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.mric.2019.08.003DOI Listing
February 2020

Canadian Association of Radiologists Position Statement on Point-of-Care Ultrasound.

Can Assoc Radiol J 2019 Aug;70(3):219-225

Department of Radiology, McMaster University, Hamilton, Ontario, Canada.

View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.carj.2019.06.001DOI Listing
August 2019

Usefulness of diffusion-weighted MRI in the initial assessment of osseous sarcomas in children and adolescents.

Pediatr Radiol 2019 08 15;49(9):1201-1208. Epub 2019 Jun 15.

Department of Diagnostic Imaging, The Hospital for Sick Children, 555 University Ave., Toronto, ON, M5G 1X8, Canada.

Background: Concern regarding gadolinium deposition in the brain after repeated administration of intravenous gadolinium-based contrast agents has prompted evaluation of imaging alternatives.

Objective: The study purpose was to determine if magnetic resonance imaging (MRI) using conventional sequences with diffusion-weighted imaging (DWI) instead of gadolinium-based contrast-enhanced MRI is valid for local staging and guiding biopsies in osseous sarcomas.

Materials And Methods: Initial pretreatment MRI with DWI and gadolinium-based contrast-enhanced images in patients ≤ 18 years with histopathologically proven osseous sarcomas were included. Two radiologists blinded to collated demographic and clinical data, independently reviewed conventional/DWI and conventional/gadolinium-based contrast-enhanced MRI then conventional sequences alone, recording tumor size, skip lesions, necrosis, neurovascular invasion, enlarged lymph nodes and diffusion restriction. Discrepancies were resolved by a third reader. A single reader measured apparent diffusion coefficient (ADC) values in non-necrotic tumors, then correlated minimum ADC values -- with and without normalization to skeletal muscle -- with relative enhancement.

Results: Twenty-one patients (mean age: 11.3±4.2 years, 15 [71%] females) had 14 osteosarcomas and 7 Ewing sarcomas, 50% centered in the femur. Conventional/DWI versus conventional/gadolinium-based contrast-enhanced MRI showed agreement for tumor size estimation with significant associations for necrosis (P=0.021), neurovascular involvement (P<0.001) and enlarged lymph nodes (P=0.005). Diagnostic accuracy of conventional/DWI is comparable to conventional/gadolinium-based contrast-enhanced MRI and superior to conventional sequences alone. Comparison between minimum ADC values and relative enhancement showed no correlation (P>0.05).

Conclusion: Significant associations of key imaging features in the initial assessment of osseous sarcomas support DWI as an alternative to gadolinium-based contrast-enhanced MRI. The lack of association between ADC values and relative enhancement suggests that they measure independent constructs, DWI dependent upon tumor cellularity and perfusion.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1007/s00247-019-04436-yDOI Listing
August 2019

Easing anxiety in preparation for pediatric magnetic resonance imaging: a pilot study using animal-assisted therapy.

Pediatr Radiol 2019 07 27;49(8):1000-1009. Epub 2019 Apr 27.

Department of Diagnostic Imaging, The Hospital for Sick Children, 555 University Ave., Toronto, ON, M5G 1X8, Canada.

Background: Children undergoing magnetic resonance imaging (MRI) can experience negative emotions both before and during their scan, causing them to move and often necessitating the use of procedural sedation. Several strategies to improve patient compliance have been attempted.

Objective: This study was designed to evaluate the effectiveness of a non-pharmacological intervention to reduce anxiety in pediatric patients preparing for MRI using animal-assisted therapy.

Materials And Methods: An animal intervention pilot study was performed in patients who agreed in advance to interact with a dog. Patients and caregivers filled out questionnaires, including questions designed to capture changes in patient emotion before and after the intervention. MRI diagnostic quality was compared to age- and gender-matched control groups with and without general anesthesia.

Results: The intervention in 21 patients comparing pre- and post-scan surveys demonstrated a statistically significant improvement in patient anxiety levels (P<0.01). Diagnostic MRI scans were achieved in 19/21 (90%), with no significant difference in exam quality or times compared against control groups. The majority of caregivers and staff members agreed strongly that patients benefited from the therapy dog's presence.

Conclusion: The use of animal-assisted therapy in a pilot group in our MRI division resulted in a beneficial effect on patients' emotional status, easing anxiety in preparation for scheduled scans, without impacting MRI quality or duration. Further randomized studies will be needed to demonstrate its significance in reducing sedation rates in children undergoing MRI.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1007/s00247-019-04407-3DOI Listing
July 2019

Current and Emerging Roles of Whole-Body MRI in Evaluation of Pediatric Cancer Patients.

Radiographics 2019 Mar-Apr;39(2):516-534. Epub 2019 Jan 25.

From the Department of Radiology, Massachusetts General Hospital, Boston, Mass (R.V.G., M.S.G., P.J.H.); Department of Diagnostic Imaging, the Hospital for Sick Children, 555 University Ave, Toronto, ON, Canada M5G 1X8 (M.L.C.G.); and Department of Medical Imaging, University of Toronto, Toronto, Ont, Canada (M.L.C.G.).

Imaging is fundamental to diagnosis and management of pediatric patients with cancer and cancer predisposition syndromes (CPSs). Whole-body MRI has emerged as a versatile tool for pediatric oncologic imaging, with the potential to spare children from ionizing radiation imparted by conventional modalities such as CT and PET. Whole-body MRI also enables simultaneous high-resolution local-regional staging and wide field-of-view distant staging in the same imaging session, with superior evaluation of the brain, spine, liver, and marrow. Recent technical advances have reduced imaging times and enhanced image quality, with continued advances on the near horizon. Pulse sequences such as whole-body diffusion-weighted imaging have also broadened the range of diagnostic information obtainable. In addition, increasing identification of children with CPSs has compelled efforts to establish surveillance imaging strategies for affected individuals, with whole-body MRI playing a pivotal role in screening algorithms for several CPSs. In light of these emerging trends, a working knowledge of oncologic whole-body MRI applications and evolving CPS surveillance algorithms is vital to providers who participate in the care of pediatric patients affected by or predisposed to cancer. Recognizing both the strengths and limitations of whole-body MRI not only enables more thoughtful implementation but also improves the accuracy of image interpretation. RSNA, 2019 See discussion on this article by Khanna .
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1148/rg.2019180130DOI Listing
March 2020

Imaging of cancer predisposition syndromes.

Pediatr Radiol 2018 08 4;48(9):1364-1375. Epub 2018 Aug 4.

Department of Diagnostic Imaging, The Hospital for Sick Children, Department of Medical Imaging, University of Toronto, 555 University Ave., Toronto, ON, M5G 1X8, Canada.

Pediatric cancer predisposition syndromes comprise a group of diseases characterized by specific tumors or a concomitance of tumors in infants, children and adolescents, suggesting a genetic cancer susceptibility condition. Most but not all have germline pathogenic variants on genetic testing. For some children with cancer predisposition syndromes, this diagnosis is based on their own or a family history of related neoplasms, or associated clinical manifestations. These tumors have variable incidence and age of onset. Imaging encompasses investigation in symptomatic children for diagnosis, staging and monitoring for treatment response and metastatic disease, as well as surveillance for primary tumors in asymptomatic children. In this review the author focuses on the role of surveillance imaging in childhood cancer predisposition syndromes, whole-body magnetic resonance imaging (whole-body MRI) in particular. Diagnosis and staging of specific tumors are addressed elsewhere in this series. The benefits of surveillance imaging include early detection and improved outcomes and are still being established for a number of cancer predisposition syndromes. The benefits must be weighed against risks including potential technique-related issues relating to sedation or contrast agents, false-positive imaging findings, and cost - both financial and psychosocial. The author discusses general principles for whole-body MRI interpretation along with findings in specific syndromes where whole-body MRI screening is recommended, such as Li-Fraumeni syndrome.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1007/s00247-018-4113-0DOI Listing
August 2018

Whole-body magnetic resonance imaging: techniques and non-oncologic indications.

Pediatr Radiol 2018 08 4;48(9):1348-1363. Epub 2018 Aug 4.

Department of Diagnostic Imaging, The Hospital for Sick Children, 555 University Ave., Toronto, ON,, M5G 1X8, Canada.

Whole-body MRI is increasingly utilized for assessing oncologic and non-oncologic diseases in infants, children and adolescents. Focusing on the non-oncologic indications, this review covers technical elements required to perform whole-body MRI, the advantages and limitations of the technique, and protocol modifications tailored to specific indications. Rheumatologic diseases account for the majority of non-oncologic whole-body MRI performed in pediatric patients at the author's institution. Whole-body MRI helps in establishing the diagnosis, documenting disease extent and severity, and monitoring treatment response in enthesitis-related arthritis (ERA) and chronic recurrent multifocal osteomyelitis (CRMO). Other non-oncologic indications for whole-body MRI include osteomyelitis (usually pyogenic), pyrexia of unknown origin, neuromuscular disorders, inherited and inflammatory myopathies such as juvenile dermatomyositis and polymyositis, avascular necrosis, and fat/storage disorders. Use of whole-body MRI in postmortem imaging is rising, while whole-body MRI in non-accidental injury is considered to be of limited value. Imaging findings for a range of these indications are reviewed with whole-body MRI examples.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1007/s00247-018-4141-9DOI Listing
August 2018

Paediatric magnetic resonance enterography in inflammatory bowel disease.

Eur J Radiol 2018 May 7;102:129-137. Epub 2018 Mar 7.

Department of Diagnostic Imaging, The Hospital for Sick Children, 555 University Avenue, Toronto, ON, M5G 1X8, Canada; Department of Medical Imaging, University of Toronto, 263 McCaul Street, Toronto, ON, M5T 1W7, Canada. Electronic address:

Paediatric magnetic resonance enterography (MRE) has been increasingly employed in the evaluation of inflammatory bowel disease (IBD) in the past decade. This is in parallel with a global rise in paediatric-onset IBD, greater recognition of the hazards of ionizing radiation, especially in children, and improved treatment options. MRE is now the reference standard for assessing the small bowel in suspected or proven paediatric IBD, and is central to the diagnosis of Crohn's disease (CD), helping distinguish it from ulcerative colitis. This review will discuss the standard and advanced techniques applied in paediatric MRE to define the presence, extent and severity of intestinal IBD, and increasingly colonic and perianal disease. Its role in demonstrating enteric and extra-enteric disease and characterizing this as active inflammation and/or damage will be explored, including the utility of cinematic, diffusion weighted and magnetization transfer imaging. While MRE is increasingly used to guide medical versus surgical management, considerable overlap exists between conventional MRE imaging features for inflammation and damage, as reflected pathologically, which is driving ongoing research. Paediatric MRE-based scoring systems for CD are currently under development that will further consolidate the role of MRE in paediatric IBD, reinforced by implementation of standardized analysis, interpretation and reporting. As an imaging biomarker, MRE performs well when referenced against endoscopy and clinical biomarkers for evidence of mucosal healing, the current treatment goal. MRE is anticipated to have even greater impact as an imaging biomarker through demonstration of transmural disease and healing, not amenable to endoscopic assessment.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.ejrad.2018.02.029DOI Listing
May 2018

Magnetic Resonance Enterography Cannot Replace Upper Endoscopy in Pediatric Crohn Disease: An Imagekids Sub-study.

J Pediatr Gastroenterol Nutr 2018 07;67(1):53-58

Sick Kids Inflammatory Bowel Disease Centre, The Hospital for Sick Children, Toronto.

Objectives: Although magnetic resonance enterography (MRE) can accurately reflect ileal inflammation in pediatric Crohn disease (CD), there are no pediatric data on the accuracy of MRE to detect upper gastrointestinal tract (UGI) lesions. We aimed to compare MRE and esophagogastroduodenoscopy (EGD) in detecting the spectrum and severity of UGI disease in children.

Methods: This is an ancillary study of the prospective multi-center ImageKids study focusing on pediatric MRE. EGD was performed within 2 weeks of MRE (at disease onset or thereafter) and explicitly scored by SES-CD modified for the UGI and physician global assessment. Local and central radiologists scored the UGI region of the MRE blinded to the EGD. Accuracy of MRE compared with EGD was examined using correlational coefficients (r) and area under receiver operating characteristic curves (AUC).

Results: One hundred and eighty-eight patients were reviewed (mean age 14 ± 1 years, 103 [55%] boys); 66 of 188 (35%) children had macroscopic ulcerations on EGD (esophagus, 13 [7%]; stomach, 34 [18%]; duodenum, 45 [24%]). Most children had aphthous ulcers, but 10 (5%) had larger ulcers (stomach, 2 [1%]; duodenum, 8 [4%]). There was no agreement between local and central radiologists on the presence or absence of UGI inflammation on MRE (Kappa = -0.02, P = 0.71). EGD findings were not accurately detected by MRE, read locally or centrally (r = -0.03 to 0.11, P = 0.18-0.88; AUC = 0.47-0.55, P = 0.53-1.00).No fistulae or narrowings were identified on either EGD or MRE.

Conclusions: MRE cannot reliably assess the UGI in pediatric CD and cannot replace EGD for this purpose.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1097/MPG.0000000000001869DOI Listing
July 2018

Can MR enterography screen for perianal disease in pediatric inflammatory bowel disease?

J Magn Reson Imaging 2018 06 14;47(6):1638-1645. Epub 2017 Nov 14.

Department of Diagnostic Imaging, The Hospital for Sick Children, Toronto, Canada.

Background: Pediatric Crohn's disease is associated with perianal disease (PAD). Magnetic resonance enterography (MRE) assesses small bowel involvement in pediatric inflammatory bowel disease (PIBD). Pelvic MRI (P-MRI) is the gold standard for assessing PAD.

Purpose: To determine if MRE can accurately detect PAD in PIBD, distinguishing perianal fistulae (PAF) from perianal abscesses (PAA), referenced against P-MRI.

Study Type: Retrospective.

Population: Seventy-seven PIBD patients, 27 females (mean age 14.1 years), with P-MRI and MRE within 6 months.

Field Strength/sequence: 1.5T and 3T; P-MRI: sagittal fat suppressed (FS) T fast spin-echo (FSE), coronal short tau inversion recovery, axial T FSE, coronal and axial postcontrast FS T FSE; MRE: coronal balanced steady-state free-precession (SSFP), coronal cine SSFP, coronal and axial single-shot T FS, axial SSFP, coronal ultrafast 3D T -weighted gradient echo FS (3D T GE), axial diffusion-weighted imaging, coronal and axial postcontrast 3D T GE FS.

Assessment: Two radiologists independently, then by consensus, assessed randomized MRI exams, recording PAF number, location, and length; and PAA number, location, length, and volume. Sensitivity analysis used clinical disease as the gold standard, calculated separately for P-MRI and MRE.

Statistical Tests: Comparing MRE and P-MRI consensus data, sensitivity, specificity, positive, and negative predictive values (P/NPV) were calculated. Inter- and intrareader reliability were assessed using kappa statistics.

Results: P-MRI and MRE were paired, detecting PAD in 73 patients, PAF in 63, and PAA in 31 P-MRI. MRE sensitivities, specificities, PPV, and NPV were: PAD 82%, 100%, 100%, 23%; PAF 74%, 71%, 92%, 38%; PAA 51%, 85%, 69%, 72%; clinical 82%, 22%, 37%, 69%; clinical P-MRI 96%, 8%, 37%, 80%. MRE interreader agreement for PAD was moderate (kappa = 0.51 [0.29-0.73]), fair for PAF and PAA.

Data Conclusion: Using a standard technique, MRE can detect PAD with high specificity and moderate sensitivity in PIBD, missing some PAF and small PAA.

Level Of Evidence: 3 Technical Efficacy: Stage 2 J. Magn. Reson. Imaging 2018;47:1638-1645.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1002/jmri.25888DOI Listing
June 2018

DICER1 syndrome: Approach to testing and management at a large pediatric tertiary care center.

Pediatr Blood Cancer 2018 Jan 27;65(1). Epub 2017 Sep 27.

Division of Hematology/Oncology, The Hospital for Sick Children, Toronto, Ontario, Canada.

Background: To expand the current knowledge of DICER1 syndrome and to propose criteria for genetic testing based on experience at a pediatric tertiary care center.

Procedure: This study involved a retrospective chart review of the 78 patients (47 probands and 31 family members) seen in the Cancer Genetics Program at The Hospital for Sick Children (SickKids) who were offered genetic testing for DICER1.

Results: Of 47 probands offered genetic testing for DICER1, 46 pursued testing: 11 (23.9%) carried a pathogenic variant and one proband (2.1%) carried a missense variant of uncertain significance with evidence for pathogenicity. Thirty-one family members of variant-positive probands were offered testing: eight of the 25 who agreed to testing carried their familial variant (32.0%). Overall, 20 patients were identified to have a variant in DICER1 (eight males, 12 females). Of these, 13 (65.0%) presented with clinical manifestations associated with the syndrome. The most common lesions were pleuropulmonary blastoma (PPB) (five of 20 patients, 25.0%) and pineoblastoma (three of 20 patients, 15.0%). The average age at which individuals were diagnosed with a primary neoplasm was 5.2 years (range 0.8-20 years, median 3.0). Surveillance at our institution, with a median follow-up time of 23 months, has identified PPB in two asymptomatic individuals. These lesions were identified at early stages, thus potentially reducing treatment-related morbidity and mortality.

Conclusion: This study further delineates the DICER1 syndrome phenotype and demonstrates the feasibility of a DICER1 syndrome surveillance protocol for the early detection of tumors.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1002/pbc.26720DOI Listing
January 2018

Recommendations for Cancer Surveillance in Individuals with RASopathies and Other Rare Genetic Conditions with Increased Cancer Risk.

Clin Cancer Res 2017 Jun;23(12):e83-e90

Pediatric Hematology and Oncology, Hannover Medical School, Hannover, Germany.

In October 2016, the American Association for Cancer Research held a meeting of international childhood cancer predisposition syndrome experts to evaluate the current knowledge of these syndromes and to propose consensus surveillance recommendations. Herein, we summarize clinical and genetic aspects of RASopathies and Sotos, Weaver, Rubinstein-Taybi, Schinzel-Giedion, and NKX2-1 syndromes as well as specific metabolic disorders known to be associated with increased childhood cancer risk. In addition, the expert panel reviewed whether sufficient data exist to make a recommendation that all patients with these disorders be offered cancer surveillance. For all syndromes, the panel recommends increased awareness and prompt assessment of clinical symptoms. Patients with Costello syndrome have the highest cancer risk, and cancer surveillance should be considered. Regular physical examinations and complete blood counts can be performed in infants with Noonan syndrome if specific or mutations are present, and in patients with CBL syndrome. Also, the high brain tumor risk in patients with L-2 hydroxyglutaric aciduria may warrant regular screening with brain MRIs. For most syndromes, surveillance may be needed for nonmalignant health problems.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1158/1078-0432.CCR-17-0631DOI Listing
June 2017

Cancer Screening Recommendations for Individuals with Li-Fraumeni Syndrome.

Clin Cancer Res 2017 06;23(11):e38-e45

Division of Endocrinology, The Hospital for Sick Children, Department of Pediatrics, University of Toronto, Toronto, Ontario, Canada.

Li-Fraumeni syndrome (LFS) is an autosomal dominantly inherited condition caused by germline mutations of the tumor suppressor gene encoding p53, a transcription factor triggered as a protective cellular mechanism against different stressors. Loss of p53 function renders affected individuals highly susceptible to a broad range of solid and hematologic cancers. It has recently become evident that children and adults with LFS benefit from intensive surveillance aimed at early tumor detection. In October 2016, the American Association for Cancer Research held a meeting of international LFS experts to evaluate the current knowledge on LFS and propose consensus surveillance recommendations. Herein, we briefly summarize clinical and genetic aspects of this aggressive cancer predisposition syndrome. In addition, the expert panel concludes that there are sufficient existing data to recommend that all patients with LFS be offered cancer surveillance as soon as the clinical or molecular LFS diagnosis is established. Specifically, the panel recommends adoption of a modified version of the "Toronto protocol" that includes a combination of physical exams, blood tests, and imaging. The panel also recommends that further research be promoted to explore the feasibility and effectiveness of these risk-adapted surveillance and cancer prevention strategies while addressing the psychosocial needs of individuals and families with LFS.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1158/1078-0432.CCR-17-0408DOI Listing
June 2017

Pediatric Cancer Predisposition Imaging: Focus on Whole-Body MRI.

Clin Cancer Res 2017 Jun;23(11):e6-e13

Department of Radiology, Children's Hospital of Philadelphia (CHOP), Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania.

The American Association for Cancer Research convened a meeting of international pediatric oncologists, geneticists, genetic counselors, and radiologists expert in childhood cancer predisposition syndromes (CPS) in October 2016 to propose consensus surveillance guidelines. Imaging plays a central role in surveillance for most, though not all, syndromes discussed. While encompassing the full gamut of modalities, there is increasing emphasis on use of nonionizing radiation imaging options such as magnetic resonance imaging (MRI) in children and adolescents, especially in the pediatric CPS population. In view of rapid evolution and widespread adoption of whole-body MRI (WBMRI), the purpose of our review is to address WBMRI in detail. We discuss its place in the surveillance of a range of pediatric CPS, the technical and logistical aspects of acquiring and interpreting these studies, and the inherent limitations of WBMRI. We also address issues associated with sedation and use of gadolinium-based contrast agents in MRI in children.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1158/1078-0432.CCR-17-0515DOI Listing
June 2017

Pediatric imaging in DICER1 syndrome.

Pediatr Radiol 2017 Sep 4;47(10):1292-1301. Epub 2017 May 4.

Department of Diagnostic Imaging, The Hospital for Sick Children, 555 University Ave., Toronto, Ontario, M5G 1X8, Canada.

Background: DICER1 syndrome, arising from a mutation in the DICER1 gene mapped to chromosome 14q32, is associated with an increased risk of a range of benign and malignant neoplasms.

Objective: To determine the spectrum of abnormalities and imaging characteristics in patients with DICER1 syndrome at a tertiary pediatric hospital.

Materials And Methods: This retrospective analysis evaluated imaging in patients ≤18 years with DICER1 germline variants between January 2004 and July 2016. An imaging database search including keywords pleuropulmonary blastoma, cystic nephroma, pineoblastoma, embryonal rhabdomyosarcoma, ovarian sex cord-stromal tumor, ovarian Sertoli-Leydig cell tumor and DICER1 syndrome, was cross-referenced against the institutional Cancer Genetics Program database, excluding patients with negative/unknown DICER1 gene testing.

Results: Sixteen patients were included (12 females; mean age at presentation: 4.2 years, range: 14 days to 17 years), with surveillance imaging encompassing the following modalities: chest X-ray and CT; abdominal, pelvic and neck US; and brain and whole-body MRI. Malignant lesions (68.8% of patients) included pleuropulmonary blastoma (5), pineoblastoma (3), ovarian Sertoli-Leydig cell tumor (1), embryonal rhabdomyosarcoma (1) and renal sarcoma (1); benign lesions (37.5% of patients) included thyroid cysts (2), thyroid nodules (2), cystic nephroma (2), renal cysts (1) and pineal cyst (1). A common lesional appearance observed across modalities and organs was defined as the "cracked windshield" sign.

Conclusion: The spectrum of DICER1-related tumors and the young age at presentation suggest early surveillance of at-risk patients is critical, while minimizing exposure to ionizing radiation.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1007/s00247-017-3875-0DOI Listing
September 2017

The role of imaging in the preoperative assessment of children with inflammatory colitis.

J Pediatr Surg 2017 Jun 18;52(6):970-974. Epub 2017 Mar 18.

Division of General and Thoracic Surgery, The Hospital for Sick Children, Toronto, Ontario, Canada. Electronic address:

Background: Accurate diagnosis of Crohn's disease or ulcerative colitis is essential for surgical planning. This study compared the accuracy, safety, and utility of small bowel follow-through (SBFT) and magnetic resonance enterography (MRE) for detecting small bowel (SB) involvement preoperatively.

Methods: A retrospective review of children who underwent colectomy for inflammatory bowel disease (2000-2014) was performed. Preoperative SBFT and MRE were independently reviewed by two radiologists blinded to clinical data. Gold standard for diagnosis was surgical pathology.

Results: 68 patients (36 female) were included. 45 patients had SBFT prior to colectomy, 17 patients had MRE, and 6 both. Interrater reliability for radiologic interpretation was 90% (SBFT) and 91% (MRE). Mean study durations were 190min (SBFT) and 59min (MRE). Median effective dose for SBFT was 1.5mSv, while MRE involved no ionizing radiation. Specificities for diagnosing SB involvement were 87.5% (SBFT) and 94% (MRE). 54 patients underwent subtotal colectomy and ileostomy, 12 restorative proctocolectomy, and 2 colectomy with ileorectal anastomosis. Preoperative imaging correlated with surgical pathology in 83% (SBFT) and 90% (MRE).

Conclusion: MRE is at least as effective as SBFT for assessing SB disease in children with colitis prior to colectomy. MRE requires less time and does not expose children to ionizing radiation. Retrospective Case Series, Level 4 Evidence.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.jpedsurg.2017.03.019DOI Listing
June 2017