1
|
Tanaka F, Maeda M, Nakayama R, Inoue K, Kishi S, Kogue R, Umino M, Kitano Y, Obara M, Sakuma H. A Combination of Amide Proton Transfer, Tumor Blood Flow, and Apparent Diffusion Coefficient Histogram Analysis Is Useful for Differentiating Malignant from Benign Intracranial Tumors in Young Patients: A Preliminary Study. Diagnostics (Basel) 2024; 14:1236. [PMID: 38928651 PMCID: PMC11202847 DOI: 10.3390/diagnostics14121236] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2024] [Revised: 06/06/2024] [Accepted: 06/08/2024] [Indexed: 06/28/2024] Open
Abstract
PURPOSE To evaluate the amide proton transfer (APT), tumor blood flow (TBF), and apparent diffusion coefficient (ADC) combined diagnostic value for differentiating intracranial malignant tumors (MTs) from benign tumors (BTs) in young patients, as defined by the 2021 World Health Organization classification of central nervous system tumors. METHODS Fifteen patients with intracranial MTs and 10 patients with BTs aged 0-30 years underwent MRI with APT, pseudocontinuous arterial spin labeling (pCASL), and diffusion-weighted imaging. All tumors were evaluated through the use of histogram analysis and the Mann-Whitney U test to compare 10 parameters for each sequence between the groups. The diagnostic performance was evaluated using receiver operating characteristic (ROC) curve analysis. RESULTS The APT maximum, mean, 10th, 25th, 50th, 75th, and 90th percentiles were significantly higher in MTs than in BTs; the TBF minimum (min) was significantly lower in MTs than in BTs; TBF kurtosis was significantly higher in MTs than in BTs; the ADC min, 10th, and 25th percentiles were significantly lower in MTs than in BTs (all p < 0.05). The APT 50th percentile (0.900), TBF min (0.813), and ADC min (0.900) had the highest area under the curve (AUC) values of the parameters in each sequence. The AUC for the combination of these three parameters was 0.933. CONCLUSIONS The combination of APT, TBF, and ADC evaluated through histogram analysis may be useful for differentiating intracranial MTs from BTs in young patients.
Collapse
Affiliation(s)
- Fumine Tanaka
- Department of Radiology, Mie University School of Medicine, 2-174 Edobashi, Tsu 5148507, Mie, Japan
| | - Masayuki Maeda
- Department of Neuroradiology, Mie University School of Medicine, 2-174 Edobashi, Tsu 5148507, Mie, Japan
| | - Ryohei Nakayama
- Department of Electronic and Computer Engineering, Ritsumeikan University, 1-1-1 Noji-higashi, Kusatsu 5250058, Shiga, Japan
| | - Katsuhiro Inoue
- Department of Radiology, Mie University Hospital, 2-174 Edobashi, Tsu 5148507, Mie, Japan
| | - Seiya Kishi
- Department of Radiology, Mie University School of Medicine, 2-174 Edobashi, Tsu 5148507, Mie, Japan
| | - Ryota Kogue
- Department of Radiology, Mie University School of Medicine, 2-174 Edobashi, Tsu 5148507, Mie, Japan
| | - Maki Umino
- Department of Radiology, Mie University School of Medicine, 2-174 Edobashi, Tsu 5148507, Mie, Japan
| | - Yotaro Kitano
- Department of Neurosurgery, Mie University School of Medicine, 2-174 Edobashi, Tsu 5148507, Mie, Japan
| | - Makoto Obara
- MR Clinical Science, Philips Japan, 2-13-37 Konan, Minato 1088507, Tokyo, Japan
| | - Hajime Sakuma
- Department of Radiology, Mie University School of Medicine, 2-174 Edobashi, Tsu 5148507, Mie, Japan
| |
Collapse
|
2
|
Tanyel T, Nadarajan C, Duc NM, Keserci B. Deciphering Machine Learning Decisions to Distinguish between Posterior Fossa Tumor Types Using MRI Features: What Do the Data Tell Us? Cancers (Basel) 2023; 15:4015. [PMID: 37627043 PMCID: PMC10452543 DOI: 10.3390/cancers15164015] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2023] [Revised: 07/22/2023] [Accepted: 08/02/2023] [Indexed: 08/27/2023] Open
Abstract
Machine learning (ML) models have become capable of making critical decisions on our behalf. Nevertheless, due to complexity of these models, interpreting their decisions can be challenging, and humans cannot always control them. This paper provides explanations of decisions made by ML models in diagnosing four types of posterior fossa tumors: medulloblastoma, ependymoma, pilocytic astrocytoma, and brainstem glioma. The proposed methodology involves data analysis using kernel density estimations with Gaussian distributions to examine individual MRI features, conducting an analysis on the relationships between these features, and performing a comprehensive analysis of ML model behavior. This approach offers a simple yet informative and reliable means of identifying and validating distinguishable MRI features for the diagnosis of pediatric brain tumors. By presenting a comprehensive analysis of the responses of the four pediatric tumor types to each other and to ML models in a single source, this study aims to bridge the knowledge gap in the existing literature concerning the relationship between ML and medical outcomes. The results highlight that employing a simplistic approach in the absence of very large datasets leads to significantly more pronounced and explainable outcomes, as expected. Additionally, the study also demonstrates that the pre-analysis results consistently align with the outputs of the ML models and the clinical findings reported in the existing literature.
Collapse
Affiliation(s)
- Toygar Tanyel
- Department of Computer Engineering, Yildiz Technical University, Istanbul 34349, Türkiye;
| | - Chandran Nadarajan
- Department of Radiology, Gleneagles Hospital Kota Kinabalu, Kota Kinabalu 88100, Sabah, Malaysia;
| | - Nguyen Minh Duc
- Department of Radiology, Pham Ngoc Thach University of Medicine, Ho Chi Minh City 700000, Vietnam;
| | - Bilgin Keserci
- Department of Biomedical Engineering, Yildiz Technical University, Istanbul 34349, Türkiye
| |
Collapse
|
3
|
Deep Learning Classifies Low- and High-Grade Glioma Patients with High Accuracy, Sensitivity, and Specificity Based on Their Brain White Matter Networks Derived from Diffusion Tensor Imaging. Diagnostics (Basel) 2022; 12:diagnostics12123216. [PMID: 36553224 PMCID: PMC9777902 DOI: 10.3390/diagnostics12123216] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2022] [Revised: 12/04/2022] [Accepted: 12/13/2022] [Indexed: 12/23/2022] Open
Abstract
Classifying low-grade glioma (LGG) patients from high-grade glioma (HGG) is one of the most challenging tasks in planning treatment strategies for brain tumor patients. Previous studies derived several handcrafted features based on the tumor's texture and volume from magnetic resonance images (MRI) to classify LGG and HGG patients. The accuracy of classification was moderate. We aimed to classify LGG from HGG with high accuracy using the brain white matter (WM) network connectivity matrix constructed using diffusion tensor tractography. We obtained diffusion tensor images (DTI) of 44 LGG and 48 HGG patients using routine clinical imaging. Fiber tractography and brain parcellation were performed for each patient to obtain the fractional anisotropy, axial diffusivity, radial diffusivity, and mean diffusivity weighted connectivity matrices. We used a deep convolutional neural network (DNN) for classification and the gradient class activation map (GRAD-CAM) technique to identify the neural connectivity features focused on by the DNN. DNN could classify both LGG and HGG with 98% accuracy. The sensitivity and specificity values were above 0.98. GRAD-CAM analysis revealed a distinct WM network pattern between LGG and HGG patients in the frontal, temporal, and parietal lobes. Our results demonstrate that glioma affects the WM network in LGG and HGG patients differently.
Collapse
|
4
|
Withey SB, MacPherson L, Oates A, Powell S, Novak J, Abernethy L, Pizer B, Grundy R, Morgan PS, Bailey S, Mitra D, Arvanitis TN, Auer DP, Avula S, Peet AC. Dynamic susceptibility-contrast magnetic resonance imaging with contrast agent leakage correction aids in predicting grade in pediatric brain tumours: a multicenter study. Pediatr Radiol 2022; 52:1134-1149. [PMID: 35290489 PMCID: PMC9107460 DOI: 10.1007/s00247-021-05266-7] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/29/2020] [Revised: 08/31/2021] [Accepted: 12/11/2021] [Indexed: 11/30/2022]
Abstract
BACKGROUND Relative cerebral blood volume (rCBV) measured using dynamic susceptibility-contrast MRI can differentiate between low- and high-grade pediatric brain tumors. Multicenter studies are required for translation into clinical practice. OBJECTIVE We compared leakage-corrected dynamic susceptibility-contrast MRI perfusion parameters acquired at multiple centers in low- and high-grade pediatric brain tumors. MATERIALS AND METHODS Eighty-five pediatric patients underwent pre-treatment dynamic susceptibility-contrast MRI scans at four centers. MRI protocols were variable. We analyzed data using the Boxerman leakage-correction method producing pixel-by-pixel estimates of leakage-uncorrected (rCBVuncorr) and corrected (rCBVcorr) relative cerebral blood volume, and the leakage parameter, K2. Histological diagnoses were obtained. Tumors were classified by high-grade tumor. We compared whole-tumor median perfusion parameters between low- and high-grade tumors and across tumor types. RESULTS Forty tumors were classified as low grade, 45 as high grade. Mean whole-tumor median rCBVuncorr was higher in high-grade tumors than low-grade tumors (mean ± standard deviation [SD] = 2.37±2.61 vs. -0.14±5.55; P<0.01). Average median rCBV increased following leakage correction (2.54±1.63 vs. 1.68±1.36; P=0.010), remaining higher in high-grade tumors than low grade-tumors. Low-grade tumors, particularly pilocytic astrocytomas, showed T1-dominant leakage effects; high-grade tumors showed T2*-dominance (mean K2=0.017±0.049 vs. 0.002±0.017). Parameters varied with tumor type but not center. Median rCBVuncorr was higher (mean = 1.49 vs. 0.49; P=0.015) and K2 lower (mean = 0.005 vs. 0.016; P=0.013) in children who received a pre-bolus of contrast agent compared to those who did not. Leakage correction removed the difference. CONCLUSION Dynamic susceptibility-contrast MRI acquired at multiple centers helped distinguish between children's brain tumors. Relative cerebral blood volume was significantly higher in high-grade compared to low-grade tumors and differed among common tumor types. Vessel leakage correction is required to provide accurate rCBV, particularly in low-grade enhancing tumors.
Collapse
Affiliation(s)
- Stephanie B Withey
- RRPPS, University Hospitals Birmingham NHS Foundation Trust, Birmingham, UK
- Oncology, Birmingham Women's and Children's NHS Foundation Trust, Birmingham, UK
- Institute of Cancer and Genomic Sciences, University of Birmingham, Birmingham, UK
| | - Lesley MacPherson
- Radiology, Birmingham Women's and Children's NHS Foundation Trust, Birmingham, UK
| | - Adam Oates
- Radiology, Birmingham Women's and Children's NHS Foundation Trust, Birmingham, UK
| | - Stephen Powell
- Institute of Cancer and Genomic Sciences, University of Birmingham, Birmingham, UK
| | - Jan Novak
- Oncology, Birmingham Women's and Children's NHS Foundation Trust, Birmingham, UK
- Institute of Cancer and Genomic Sciences, University of Birmingham, Birmingham, UK
- Department of Psychology, Aston Brain Centre, School of Life and Health Sciences, Aston University, Birmingham, UK
| | | | - Barry Pizer
- Oncology, Alder Hey Children's NHS Foundation Trust, Liverpool, UK
| | - Richard Grundy
- The Children's Brain Tumour Research Centre, University of Nottingham, Nottingham, UK
| | - Paul S Morgan
- The Children's Brain Tumour Research Centre, University of Nottingham, Nottingham, UK
- Medical Physics, Nottingham University Hospitals, Nottingham, UK
- Division of Clinical Neuroscience, School of Medicine, University of Nottingham, Nottingham, UK
| | - Simon Bailey
- Sir James Spence Institute of Child Health, Royal Victoria Infirmary, Newcastle upon Tyne, UK
| | - Dipayan Mitra
- Neuroradiology, Royal Victoria Infirmary, Newcastle upon Tyne, UK
| | - Theodoros N Arvanitis
- Oncology, Birmingham Women's and Children's NHS Foundation Trust, Birmingham, UK
- Institute of Cancer and Genomic Sciences, University of Birmingham, Birmingham, UK
- Institute of Digital Healthcare, WMG, University of Warwick, Coventry, UK
| | - Dorothee P Auer
- Division of Clinical Neuroscience, School of Medicine, University of Nottingham, Nottingham, UK
- Neuroradiology, Nottingham University Hospitals Trust, Nottingham, UK
- NIHR Nottingham Biomedical Research Centre, Nottingham, UK
| | - Shivaram Avula
- Radiology, Alder Hey Children's NHS Foundation Trust, Liverpool, UK
| | - Andrew C Peet
- Oncology, Birmingham Women's and Children's NHS Foundation Trust, Birmingham, UK.
- Institute of Cancer and Genomic Sciences, University of Birmingham, Birmingham, UK.
- Children's Brain Tumour Research Team, 4th Floor Institute of Child Health, Birmingham Women's and Children's Hospital NHS Foundation Trust, Steelhouse Lane, Birmingham, B4 6NH, UK.
| |
Collapse
|
5
|
Dong J, Li S, Li L, Liang S, Zhang B, Meng Y, Zhang X, Zhang Y, Zhao S. Differentiation of paediatric posterior fossa tumours by the multiregional and multiparametric MRI radiomics approach: a study on the selection of optimal multiple sequences and multiregions. Br J Radiol 2022; 95:20201302. [PMID: 34767476 PMCID: PMC8722235 DOI: 10.1259/bjr.20201302] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023] Open
Abstract
OBJECTIVE To evaluate the diagnostic performance of a radiomics model based on multiregional and multiparametric MRI to classify paediatric posterior fossa tumours (PPFTs), explore the contribution of different MR sequences and tumour subregions in tumour classification, and examine whether contrast-enhanced T1 weighted (T1C) images have irreplaceable added value. METHODS This retrospective study of 136 PPFTs extracted 11,958 multiregional (enhanced, non-enhanced, and total tumour) features from multiparametric MRI (T1- and T2 weighted, T1C, fluid-attenuated inversion recovery, and diffusion-weighted images). These features were subjected to fast correlation-based feature selection and classified by a support vector machine based on different tasks. Diagnostic performances of multiregional and multiparametric MRI features, different sequences, and different tumoral regions were evaluated using multiclass and one-vs-rest strategies. RESULTS The established model achieved an overall area under the curve (AUC) of 0.977 in the validation cohort. The performance of PPFTs significantly improved after replacing T1C with apparent diffusion coefficient maps added into the plain scan sequences (AUC from 0.812 to 0.917). When oedema features were added to contrast-enhancing tumour volume, the performance did not significantly improve. CONCLUSION The radiomics model built by multiregional and multiparametric MRI features allows for the excellent distinction of different PPFTs and provides valuable references for the rational adoption of MR sequences. ADVANCES IN KNOWLEDGE This study emphasized that T1C has limited added value in predicting PPFTs and should be cautiously adopted. Selecting optimal MR sequences may help guide clinicians to better allocate acquisition sequences and reduce medical costs.
Collapse
Affiliation(s)
- Jie Dong
- School of Physics and Microelectronics, Zhengzhou University, Zhengzhou, P.R. China
| | - Suxiao Li
- School of Physics and Microelectronics, Zhengzhou University, Zhengzhou, P.R. China
| | - Lei Li
- School of Physics and Microelectronics, Zhengzhou University, Zhengzhou, P.R. China
| | | | - Bin Zhang
- School of Physics and Microelectronics, Zhengzhou University, Zhengzhou, P.R. China
| | - Yun Meng
- Department of Magnetic Resonance, The First Affiliated Hospital of Zhengzhou University, Zhengzhou, P.R. China
| | - Xiaofang Zhang
- School of Physics and Microelectronics, Zhengzhou University, Zhengzhou, P.R. China
| | - Yong Zhang
- Department of Magnetic Resonance, The First Affiliated Hospital of Zhengzhou University, Zhengzhou, P.R. China
| | - Shujun Zhao
- School of Physics and Microelectronics, Zhengzhou University, Zhengzhou, P.R. China
| |
Collapse
|
6
|
Pringle C, Kilday JP, Kamaly-Asl I, Stivaros SM. The role of artificial intelligence in paediatric neuroradiology. Pediatr Radiol 2022; 52:2159-2172. [PMID: 35347371 PMCID: PMC9537195 DOI: 10.1007/s00247-022-05322-w] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/07/2021] [Revised: 08/22/2021] [Accepted: 02/11/2022] [Indexed: 01/17/2023]
Abstract
Imaging plays a fundamental role in the managing childhood neurologic, neurosurgical and neuro-oncological disease. Employing multi-parametric MRI techniques, such as spectroscopy and diffusion- and perfusion-weighted imaging, to the radiophenotyping of neuroradiologic conditions is becoming increasingly prevalent, particularly with radiogenomic analyses correlating imaging characteristics with molecular biomarkers of disease. However, integration into routine clinical practice remains elusive. With modern multi-parametric MRI now providing additional data beyond anatomy, informing on histology, biology and physiology, such metric-rich information can present as information overload to the treating radiologist and, as such, information relevant to an individual case can become lost. Artificial intelligence techniques are capable of modelling the vast radiologic, biological and clinical datasets that accompany childhood neurologic disease, such that this information can become incorporated in upfront prognostic modelling systems, with artificial intelligence techniques providing a plausible approach to this solution. This review examines machine learning approaches than can be used to underpin such artificial intelligence applications, with exemplars for each machine learning approach from the world literature. Then, within the specific use case of paediatric neuro-oncology, we examine the potential future contribution for such artificial intelligence machine learning techniques to offer solutions for patient care in the form of decision support systems, potentially enabling personalised medicine within this domain of paediatric radiologic practice.
Collapse
Affiliation(s)
- Catherine Pringle
- Children’s Brain Tumour Research Network (CBTRN), Royal Manchester Children’s Hospital, Manchester, UK ,Division of Informatics, Imaging, and Data Sciences, School of Health Sciences, Faculty of Biology, Medicine, and Health, University of Manchester, Manchester, UK
| | - John-Paul Kilday
- Children’s Brain Tumour Research Network (CBTRN), Royal Manchester Children’s Hospital, Manchester, UK ,The Centre for Paediatric, Teenage and Young Adult Cancer, Institute of Cancer Sciences, University of Manchester, Manchester, UK
| | - Ian Kamaly-Asl
- Children’s Brain Tumour Research Network (CBTRN), Royal Manchester Children’s Hospital, Manchester, UK ,The Centre for Paediatric, Teenage and Young Adult Cancer, Institute of Cancer Sciences, University of Manchester, Manchester, UK
| | - Stavros Michael Stivaros
- Division of Informatics, Imaging, and Data Sciences, School of Health Sciences, Faculty of Biology, Medicine, and Health, University of Manchester, Manchester, UK. .,Department of Paediatric Radiology, Royal Manchester Children's Hospital, Central Manchester University Hospitals NHS Foundation Trust, Oxford Road, Manchester, M13 9WL, UK. .,The Geoffrey Jefferson Brain Research Centre, Manchester Academic Health Science Centre, University of Manchester, Manchester, UK.
| |
Collapse
|
7
|
The impact of magnetic resonance imaging spectroscopy parameters on differentiating between paediatric medulloblastoma and ependymoma. Contemp Oncol (Pozn) 2021; 25:95-99. [PMID: 34667435 PMCID: PMC8506430 DOI: 10.5114/wo.2021.105939] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2021] [Accepted: 03/26/2021] [Indexed: 12/26/2022] Open
Abstract
Introduction The distinction of medulloblastomas and ependymomas plays an important role in the care plans and prognosis of children. We aimed to investigate the role of magnetic resonance spectroscopy (MRS) in the differentiation between medulloblastomas and ependymomas in children. Materials and methods The institutional review board approved this prospective study. The brain magnetic resonance imaging protocol including axial multivoxel spectroscopy with a TE of 144 ms was assessed in 49 patients, who were divided into 2 groups: 40 patients with medulloblastomas and 9 patients with ependymomas. Receiver operating characteristic (ROC) curve analysis and the Youden index were utilized to determine the best cut-off, sensitivity, specificity, and area under the curve (AUC) values of the independent spectroscopy parameters. Results The choline level (Cho) and the choline/creatine (Cho/Cr) and choline/N-acetyl aspartate (Cho/NAA) ratios of medulloblastomas were significantly higher than those of ependymomas (p < 0.05). A Cho/NAA cut-off value of 1.24 to predict the diagnosis of medulloblastoma yielded the highest AUC and sensitivity of 80.3% and 97.5%, respectively, while a Cho cut-off value of 4.64 produced the highest specificity value of 88.9%. Conclusions Our findings suggest that Cho and Cho/NAA derived from MRS could serve as differential factors between paediatric medulloblastomas and ependymomas. Among those, a Cho/NAA cut-off value of 1.24 to predict the diagnosis of medulloblastoma generated the highest accuracy.
Collapse
|
8
|
The Diagnostic Value of Apparent Diffusion Coefficient and Proton Magnetic Resonance Spectroscopy in the Grading of Pediatric Gliomas. J Comput Assist Tomogr 2021; 45:269-276. [PMID: 33346568 PMCID: PMC7972297 DOI: 10.1097/rct.0000000000001130] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
The aims of this retrospective study were to assess the value of the quantitative analysis of apparent diffusion coefficient (ADC) and proton magnetic resonance spectroscopy (1H-MRS) metabolites in differentiating grades of pediatric gliomas.
Collapse
|
9
|
Al-Sharydah AM, Al-Abdulwahhab AH, Al-Suhibani SS, Al-Issawi WM, Al-Zahrani F, Katbi FA, Al-Thuneyyan MA, Jallul T, Mishaal Alabbas F. Posterior fossa extra-axial variations of medulloblastoma: a pictorial review as a primer for radiologists. Insights Imaging 2021; 12:43. [PMID: 33822292 PMCID: PMC8024434 DOI: 10.1186/s13244-021-00981-z] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2020] [Accepted: 03/01/2021] [Indexed: 11/29/2022] Open
Abstract
Manifestations of an atypical variant of medulloblastoma of the posterior fossa in extra-axial locations have been reported, and key questions concerning its interpretation have been raised previously. This review illustrated the clinico-radiological and histopathological features of the posterior fossa extra-axial medulloblastoma and described possible management strategies. We thoroughly reviewed all atypical anatomical locations of medulloblastoma reported within the posterior fossa and extra-axial spaces. The main characteristics of diagnostic imaging and histopathological results, primarily the distinctive radiopathological characteristics, were summarized to distinguish between intra- and extra-axial medulloblastoma, or pathologies mimicking this tumor. Most cases of posterior fossa extra-axial medulloblastoma have been reported in the cerebellopontine angle, followed by the tentorial and lateral cerebellar locations. The dural tail sign, which is commonly observed in meningioma, is rarely seen in intra- or extra-axial medulloblastoma and might be associated with other benign or malignant lesions. In addition to magnetic resonance imaging, the proposed new imaging techniques, including advances in modern neuroimaging modalities, were discussed, as potentially efficient modalities for characterizing extra-axial medulloblastoma. Radionuclide imaging and magnetic resonance perfusion imaging are practical alternatives to limit the number of differential diagnoses. We believe that medulloblastoma cases are likely under-reported because of publication bias and frequent tumors in unusual locations. Addressing these issues would help establish a more accurate understanding of this entity.
Collapse
Affiliation(s)
- Abdulaziz M Al-Sharydah
- Diagnostic and Interventional Radiology Department, Imam Abdulrahman Bin Faisal University, King Fahd Hospital of the University, AlKhobar City, Eastern Province, Saudi Arabia
| | - Abdulrahman Hamad Al-Abdulwahhab
- Diagnostic and Interventional Radiology Department, Imam Abdulrahman Bin Faisal University, King Fahd Hospital of the University, AlKhobar City, Eastern Province, Saudi Arabia.
| | - Sari Saleh Al-Suhibani
- Diagnostic and Interventional Radiology Department, Imam Abdulrahman Bin Faisal University, King Fahd Hospital of the University, AlKhobar City, Eastern Province, Saudi Arabia
| | - Wisam M Al-Issawi
- Neurosurgery Department, Imam Abdulrahman Bin Faisal University, King Fahd Hospital of the University, AlKhobar City, Eastern Province, Saudi Arabia
| | - Faisal Al-Zahrani
- Radiodiagnostics and Medical Imaging Department, King Fahd Military Medical Complex, Dhahran City, Eastern Province, Saudi Arabia
| | - Faisal Ahmad Katbi
- Emergency Department, Imam Abdulrahman Bin Faisal University, King Fahd Hospital of the University, Alkhobar City, Eastern Province, Saudi Arabia
| | - Moath Abdullah Al-Thuneyyan
- Diagnostic and Interventional Radiology Department, Imam Abdulrahman Bin Faisal University, King Fahd Hospital of the University, AlKhobar City, Eastern Province, Saudi Arabia
| | - Tarek Jallul
- Neurosurgery Department, King Fahd Specialist Hospital, Dammam City, Eastern Province, Saudi Arabia
| | - Faisal Mishaal Alabbas
- Neurosurgery Department, Imam Abdulrahman Bin Faisal University, King Fahd Hospital of the University, AlKhobar City, Eastern Province, Saudi Arabia
| |
Collapse
|
10
|
Bag AK, Chiang J, Patay Z. Radiohistogenomics of pediatric low-grade neuroepithelial tumors. Neuroradiology 2021; 63:1185-1213. [PMID: 33779771 PMCID: PMC8295117 DOI: 10.1007/s00234-021-02691-1] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2020] [Accepted: 03/10/2021] [Indexed: 12/14/2022]
Abstract
PURPOSE In addition to histology, genetic alteration is now required to classify many central nervous system (CNS) tumors according to the most recent World Health Organization CNS tumor classification scheme. Although that is still not the case for classifying pediatric low-grade neuroepithelial tumors (PLGNTs), genetic and molecular features are increasingly being used for making treatment decisions. This approach has become a standard clinical practice in many specialized pediatric cancer centers and will likely be more widely practiced in the near future. This paradigm shift in the management of PLGNTs necessitates better understanding of how genetic alterations influence histology and imaging characteristics of individual PLGNT phenotypes. METHODS The complex association of genetic alterations with histology, clinical, and imaging of each phenotype of the extremely heterogeneous PLGNT family has been addressed in a holistic approach in this up-to-date review article. A new imaging stratification scheme has been proposed based on tumor morphology, location, histology, and genetics. Imaging characteristics of each PLGNT entity are also depicted in light of histology and genetics. CONCLUSION This article reviews the association of specific genetic alteration with location, histology, imaging, and prognosis of a specific tumor of the PLGNT family and how that information can be used for better imaging of these tumors.
Collapse
Affiliation(s)
- Asim K Bag
- Department of Diagnostic Imaging, St. Jude Children's Research Hospital, 262 Danny Thomas Place, Mail Stop 220, Memphis, TN, 38105, USA.
| | - Jason Chiang
- Department of Pathology, St. Jude Children's Research Hospital, Memphis, TN, USA
| | - Zoltan Patay
- Department of Diagnostic Imaging, St. Jude Children's Research Hospital, 262 Danny Thomas Place, Mail Stop 220, Memphis, TN, 38105, USA
| |
Collapse
|
11
|
Dong J, Li L, Liang S, Zhao S, Zhang B, Meng Y, Zhang Y, Li S. Differentiation Between Ependymoma and Medulloblastoma in Children with Radiomics Approach. Acad Radiol 2021; 28:318-327. [PMID: 32222329 DOI: 10.1016/j.acra.2020.02.012] [Citation(s) in RCA: 28] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2019] [Revised: 01/31/2020] [Accepted: 02/13/2020] [Indexed: 12/14/2022]
Abstract
RATIONALE AND OBJECTIVES Ependymoma (EP) and medulloblastoma (MB) of children are similar in age, location, manifestations and symptoms. Therefore, it is difficult to differentiate them through visual observation in clinical diagnosis. The aim of this study is to investigate the effectiveness of radiomics and machine-learning techniques on multimodal magnetic resonance imaging (MRI) in distinguish EP from MB. MATERIALS AND METHODS Three dimensional (3D) tumors were semi-automatic segmented by radiologists from postcontrast T1-weighted images and apparent diffusion coefficient maps in 51 patients (24 EPs, 27 MBs). Then, we extracted radiomics features and further reduced them by three feature selection methods. For each feature selection method, 4 classifiers were adopted which yield 12 different models. After extensive crossvalidation, pairwise test were carried out in receiver operating characteristic curves to explore performance of these models. RESULTS The radiomics model built with multivariable logistic regression as feature selection method and random forests as classifier had the best performance, area under the curve achieved 0.91 (95 % confidence interval 0.787-0.968). Five relevant features were highly correlated to discriminate EP and MB, which may used as imaging biomarkers to predict the kinds of tumors. CONCLUSION The combination of radiomics and machine-learning approach on 3D multimodal MRI could well distinguish EP and MB of childhood, which assistant doctors in clinical diagnosis. Since there is no uniform model to obtained best performance for every specific data set, it is necessary to try different combination methods.
Collapse
|
12
|
Testud B, Brun G, Varoquaux A, Hak JF, Appay R, Le Troter A, Girard N, Stellmann JP. Perfusion-weighted techniques in MRI grading of pediatric cerebral tumors: efficiency of dynamic susceptibility contrast and arterial spin labeling. Neuroradiology 2021; 63:1353-1366. [PMID: 33506349 DOI: 10.1007/s00234-021-02640-y] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2020] [Accepted: 01/06/2021] [Indexed: 01/23/2023]
Abstract
PURPOSE Dynamic susceptibility contrast (DSC) and arterial spin labeling (ASL) perfusion MRI are applied in pediatric brain tumor grading, but their value for clinical daily practice remains unclear. We explored the ability of ASL and DSC to distinguish low- and high-grade lesions, in an unselected cohort of pediatric cerebral tumors. METHODS We retrospectively compared standard perfusion outcomes including blood volume, blood flow, and time parameters from DSC and ASL at 1.5T or 3T MRI scanners of 46 treatment-naive patients by drawing ROI via consensus by two neuroradiologists on the solid portions of every tumor. The discriminant abilities of perfusion parameters were evaluated by receiver operating characteristic (ROC) over the entire cohort and depending on the tumor location and the magnetic field. RESULTS ASL and DSC parameters showed overall low to moderate performances to distinguish low- and high-grade tumors (area under the curve: between 0.548 and 0.697). Discriminant abilities were better for tumors located supratentorially (AUC between 0.777 and 0.810) than infratentorially, where none of the metrics reached significance. We observed a better differentiation between low- and high-grade cancers at 3T than at 1.5-T. For infratentorial tumors, time parameters from DSC performed better than the commonly used metrics (AUC ≥ 0.8). CONCLUSION DSC and ASL show moderate abilities to distinguish low- and high-grade brain tumors in an unselected cohort. Absolute value of K2, TMAX, tMIP, and normalized value of TMAX of the DSC appear as an alternative to conventional parameters for infratentorial tumors. Three Tesla evaluation should be favored over 1.5-Tesla.
Collapse
Affiliation(s)
- B Testud
- Department of Diagnostic and Interventional Neuroradiology, APHM La Timone, 264 Saint Pierre Street, 13385, CEDEX 05, Marseille, France.
| | - G Brun
- Department of Diagnostic and Interventional Neuroradiology, APHM La Timone, 264 Saint Pierre Street, 13385, CEDEX 05, Marseille, France
| | - A Varoquaux
- APHM La Conception, Department of Medical Imaging, Aix Marseille Université, Marseille, France
| | - J F Hak
- Department of Diagnostic and Interventional Neuroradiology, APHM La Timone, 264 Saint Pierre Street, 13385, CEDEX 05, Marseille, France
| | - R Appay
- Department of Pathology and Neuropathology, APHM La Timone, Marseille, France.,Aix-Marseille Univ, CNRS, INP, Inst Neurophysiopathol, Marseille, France
| | - A Le Troter
- Aix-Marseille Univ, CNRS, CRMBM, UMR 7339, Marseille, France.,APHM La Timone, CEMEREM, Marseille, France
| | - N Girard
- Department of Diagnostic and Interventional Neuroradiology, APHM La Timone, 264 Saint Pierre Street, 13385, CEDEX 05, Marseille, France.,Aix-Marseille Univ, CNRS, CRMBM, UMR 7339, Marseille, France
| | - J P Stellmann
- Aix-Marseille Univ, CNRS, CRMBM, UMR 7339, Marseille, France.,APHM La Timone, CEMEREM, Marseille, France
| |
Collapse
|
13
|
Quon JL, Jin MC, Seekins J, Yeom KW. Harnessing the potential of artificial neural networks for pediatric patient management. Artif Intell Med 2021. [DOI: 10.1016/b978-0-12-821259-2.00021-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
|
14
|
Duc NM. The effect of semi-quantitative T1-perfusion parameters for the differentiation between pediatric medulloblastoma and ependymoma. THE EGYPTIAN JOURNAL OF RADIOLOGY AND NUCLEAR MEDICINE 2020. [DOI: 10.1186/s43055-020-00226-x] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
Abstract
Abstract
Background
The differentiation between medulloblastomas and ependymomas plays an important role in treatment planning and prognosis for children. This study aims to investigate the role of T1-perfusion parameters during the differentiation between medulloblastomas and ependymomas in children. The institutional review board approved this prospective study. The brain magnetic resonance imaging (MRI) protocol, including axial T1-perfusion, was assessed in 26 patients, divided into a medulloblastoma group (group 1, n = 22) and an ependymoma group (group 2, n = 4). The quantified region of interest (ROI) values for tumors and the tumor to parenchyma ratios were collected and compared between the two groups. Receiver operating characteristic (ROC) curve analysis and the Youden index were utilized to identify the best cut-off, sensitivity, specificity, and area under the curve (AUC) values for the independent T1-perfusion parameters.
Results
The relative enhancement, maximum enhancement, maximum relative enhancement, time to peak, and AUC values for medulloblastomas were significantly higher than those for ependymomas (p < 0.05). Furthermore, the maximum enhancement and maximum relative enhancement for medulloblastoma to parenchyma ratios were also significantly higher than those for ependymomas. A cut-off maximum enhancement value of 100.25 was identified as sufficient to discriminate between medulloblastoma and ependymoma and resulted in a sensitivity of 90.9%, a specificity of 100%, and an AUC of 94.3%.
Conclusion
A cut-off maximum enhancement value of 100.25 derived from T1-perfusion was able to discriminate between medulloblastoma and ependymoma, with high sensitivity, specificity, and accuracy values.
Collapse
|
15
|
Yan LF, Sun YZ, Zhao SS, Hu YC, Han Y, Li G, Zhang X, Tian Q, Liu ZC, Yang Y, Nan HY, Yu Y, Sun Q, Zhang J, Chen P, Hu B, Li F, Han TH, Wang W, Cui GB. Perfusion, Diffusion, Or Brain Tumor Barrier Integrity: Which Represents The Glioma Features Best? Cancer Manag Res 2019; 11:9989-10000. [PMID: 31819632 PMCID: PMC6885544 DOI: 10.2147/cmar.s197839] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2018] [Accepted: 09/30/2019] [Indexed: 12/13/2022] Open
Abstract
Purpose This study aims to incorporate informative histogram indicator analyses and advanced multimodal MRI parameters to differentiate low-grade gliomas (LGGs) from high-grade gliomas (HGGs) and to explore the features associated with patients’ survival. Patients and methods A total of 120 patients with pathologically confirmed LGGs or HGGs receiving conventional and advanced MRI such as three-dimensional arterial spin labeling (3D-ASL), intravoxel incoherent motion-diffusion weighted imaging (IVIM-DWI), and dynamic contrast-enhanced MRI (DCE-MRI) were included. The mean and histogram indicators from advanced MRI were calculated from the entire tumor. The efficacies of a single indicator or multiple parameters were tested in distinguishing HGGs from LGGs and predicting patients’ survival. Receiver operating characteristic (ROC) curve and multivariable stepwise logistic regression were used to evaluate the diagnostic efficacies. Leave-one-out cross-validation was further used to validate the accuracy of the parameter sets in glioma grading. Log-rank test using the Kaplan–Meier curve was utilized to predict patients’ survival. Results Overall, parameters from DCE-MRI performed better than those from 3D-ASL or IVIM-DWI in both glioma grading and survival prediction. The histogram metrics of Ve were demonstrated to have higher accuracies (the accuracies for Extended Tofts_Vemean and Extended Tofts_Vemedian were 68.33% and 71.67%, respectively, while those for the Incremental_Vemean and Incremental_Ve75th were 68.33% and 72.50%, respectively) in grading LGGs from HGGs. The combination of Tofts_Ve histogram metrics was the one with the highest accuracy (81.67%) and area under ROC curve (AUC = 0.840). On the other hand, Patlak_Ktrans95th (AUC = 0.9265) and Extended Tofts_Ve95th (AUC = 0.9154) performed better than their corresponding means (Patlak_Ktransmean: AUC = 0.9118 and Extended Tofts_Vemean: AUC = 0.9044) in predicting patients’ overall survival (OS) at 18-month follow-up. Conclusion DCE-MRI-derived histogram features from the entire tumor were promising metrics for glioma grading and OS prediction. Combining single modal histogram features improved glioma grading. Trial registration NCT 02622620.
Collapse
Affiliation(s)
- Lin-Feng Yan
- Department of Radiology & Functional and Molecular Imaging Key Laboratory of Shaanxi Province, Tangdu Hospital, Fourth Military Medical University, Xi'an, Shaanxi 710038, People's Republic of China
| | - Ying-Zhi Sun
- Department of Radiology & Functional and Molecular Imaging Key Laboratory of Shaanxi Province, Tangdu Hospital, Fourth Military Medical University, Xi'an, Shaanxi 710038, People's Republic of China
| | - Sha-Sha Zhao
- Department of Radiology & Functional and Molecular Imaging Key Laboratory of Shaanxi Province, Tangdu Hospital, Fourth Military Medical University, Xi'an, Shaanxi 710038, People's Republic of China
| | - Yu-Chuan Hu
- Department of Radiology & Functional and Molecular Imaging Key Laboratory of Shaanxi Province, Tangdu Hospital, Fourth Military Medical University, Xi'an, Shaanxi 710038, People's Republic of China
| | - Yu Han
- Department of Radiology & Functional and Molecular Imaging Key Laboratory of Shaanxi Province, Tangdu Hospital, Fourth Military Medical University, Xi'an, Shaanxi 710038, People's Republic of China
| | - Gang Li
- Department of Neurosurgery, Tangdu Hospital, Fourth Military Medical University, Xi'an, Shaanxi 710038, People's Republic of China
| | - Xin Zhang
- Department of Radiology & Functional and Molecular Imaging Key Laboratory of Shaanxi Province, Tangdu Hospital, Fourth Military Medical University, Xi'an, Shaanxi 710038, People's Republic of China
| | - Qiang Tian
- Department of Radiology & Functional and Molecular Imaging Key Laboratory of Shaanxi Province, Tangdu Hospital, Fourth Military Medical University, Xi'an, Shaanxi 710038, People's Republic of China
| | - Zhi-Cheng Liu
- Department of Radiology & Functional and Molecular Imaging Key Laboratory of Shaanxi Province, Tangdu Hospital, Fourth Military Medical University, Xi'an, Shaanxi 710038, People's Republic of China
| | - Yang Yang
- Department of Radiology & Functional and Molecular Imaging Key Laboratory of Shaanxi Province, Tangdu Hospital, Fourth Military Medical University, Xi'an, Shaanxi 710038, People's Republic of China
| | - Hai-Yan Nan
- Department of Radiology & Functional and Molecular Imaging Key Laboratory of Shaanxi Province, Tangdu Hospital, Fourth Military Medical University, Xi'an, Shaanxi 710038, People's Republic of China
| | - Ying Yu
- Department of Radiology & Functional and Molecular Imaging Key Laboratory of Shaanxi Province, Tangdu Hospital, Fourth Military Medical University, Xi'an, Shaanxi 710038, People's Republic of China
| | - Qian Sun
- Department of Radiology & Functional and Molecular Imaging Key Laboratory of Shaanxi Province, Tangdu Hospital, Fourth Military Medical University, Xi'an, Shaanxi 710038, People's Republic of China
| | - Jin Zhang
- Department of Radiology & Functional and Molecular Imaging Key Laboratory of Shaanxi Province, Tangdu Hospital, Fourth Military Medical University, Xi'an, Shaanxi 710038, People's Republic of China
| | - Ping Chen
- Department of Radiology & Functional and Molecular Imaging Key Laboratory of Shaanxi Province, Tangdu Hospital, Fourth Military Medical University, Xi'an, Shaanxi 710038, People's Republic of China
| | - Bo Hu
- Department of Radiology & Functional and Molecular Imaging Key Laboratory of Shaanxi Province, Tangdu Hospital, Fourth Military Medical University, Xi'an, Shaanxi 710038, People's Republic of China
| | - Fei Li
- Student Brigade, Fourth Military Medical University, Xi'an, Shaanxi 710032, People's Republic of China
| | - Teng-Hui Han
- Student Brigade, Fourth Military Medical University, Xi'an, Shaanxi 710032, People's Republic of China
| | - Wen Wang
- Department of Radiology & Functional and Molecular Imaging Key Laboratory of Shaanxi Province, Tangdu Hospital, Fourth Military Medical University, Xi'an, Shaanxi 710038, People's Republic of China
| | - Guang-Bin Cui
- Department of Radiology & Functional and Molecular Imaging Key Laboratory of Shaanxi Province, Tangdu Hospital, Fourth Military Medical University, Xi'an, Shaanxi 710038, People's Republic of China
| |
Collapse
|
16
|
Kerleroux B, Cottier JP, Janot K, Listrat A, Sirinelli D, Morel B. Posterior fossa tumors in children: Radiological tips & tricks in the age of genomic tumor classification and advance MR technology. J Neuroradiol 2019; 47:46-53. [PMID: 31541639 DOI: 10.1016/j.neurad.2019.08.002] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2018] [Revised: 08/02/2019] [Accepted: 08/02/2019] [Indexed: 01/25/2023]
Abstract
Imaging plays a major role in the comprehensive assessment of posterior fossa tumor in children (PFTC). The objective is to propose a global method relying on the combined analysis of radiological, clinical and epidemiological criteria, (taking into account the child's age and the topography of the lesion) in order to improve our histological approach in imaging, helping the management and approach for surgeons in providing information to the patients' parents. Infratentorial tumors are the most frequent in children, representing mainly medulloblastoma, pilocytic astrocytoma and brainstem glioma. Pre-surgical identification of the tumor type and its aggressiveness could be improved by the combined analysis of key imaging features with epidemiologic data.
Collapse
Affiliation(s)
- Basile Kerleroux
- Department of Pediatric Radiology, Clocheville University Hospital, CHRU Tours, Tours, France; Department of Neuroradiology, Bretonneau University Hospital, CHRU Tours, Tours, France.
| | - Jean Philippe Cottier
- Department of Neuroradiology, Bretonneau University Hospital, CHRU Tours, Tours, France; Faculty of Medicine, Francois-Rabelais University, Tours, France
| | - Kévin Janot
- Department of Neuroradiology, Bretonneau University Hospital, CHRU Tours, Tours, France; Faculty of Medicine, Francois-Rabelais University, Tours, France
| | - Antoine Listrat
- Department of Pediatric Neurosurgery, Clocheville University Hospital, CHRU Tours, Tours, France
| | - Dominique Sirinelli
- Department of Pediatric Radiology, Clocheville University Hospital, CHRU Tours, Tours, France; Faculty of Medicine, Francois-Rabelais University, Tours, France
| | - Baptiste Morel
- Department of Pediatric Radiology, Clocheville University Hospital, CHRU Tours, Tours, France; Faculty of Medicine, Francois-Rabelais University, Tours, France
| |
Collapse
|
17
|
Feng ZY, Min XD, Wang L, Li BS, Ke Z, Zhang PP, Kang Z. MRI feature analysis of uncommon prostatic malignant tumors. Asian J Androl 2019; 20:313-315. [PMID: 28566559 PMCID: PMC5952491 DOI: 10.4103/aja.aja_12_17] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023] Open
Affiliation(s)
- Zhao-Yan Feng
- The Department of Radiology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430030, China
| | - Xiang-De Min
- The Department of Radiology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430030, China
| | - Liang Wang
- The Department of Radiology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430030, China
| | - Ba-Sen Li
- The Department of Radiology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430030, China
| | - Zan Ke
- The Department of Radiology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430030, China
| | - Pei-Pei Zhang
- The Department of Radiology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430030, China
| | - Zhen Kang
- The Department of Radiology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430030, China
| |
Collapse
|
18
|
Gaudino S, Martucci M, Botto A, Ruberto E, Leone E, Infante A, Ramaglia A, Caldarelli M, Frassanito P, Triulzi FM, Colosimo C. Brain DSC MR Perfusion in Children: A Clinical Feasibility Study Using Different Technical Standards of Contrast Administration. AJNR Am J Neuroradiol 2019; 40:359-365. [PMID: 30655255 DOI: 10.3174/ajnr.a5954] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2018] [Accepted: 12/01/2018] [Indexed: 11/07/2022]
Abstract
BACKGROUND AND PURPOSE Dynamic susceptibility contrast MR perfusion imaging has limited results in children due to difficulties in reproducing technical standards derived from adults. This prospective, multicenter study aimed to determine DSC feasibility and quality in children using custom administration of a standard dose of gadolinium. MATERIALS AND METHODS Eighty-three consecutive children with brain tumors underwent DSC perfusion with a standard dose of gadobutrol administered by an automated power injector. The location and size of intravenous catheters and gadobutrol volume and flow rates were reported, and local and/or systemic adverse effects were recorded. DSC was qualitatively evaluated by CBV maps and signal intensity-time curves and quantitatively by the percentage of signal drop and full width at half-maximum, and the data were compared with the standards reported for adults. Quantitative data were grouped by flow rate, and differences among groups were assessed by analysis of covariance and tested for statistical significance with a t test. RESULTS No local or systemic adverse events were recorded independent of catheter location (63 arm, 14 hand, 6 foot), size (24-18 ga), and flow rates (1-5 mL/s). High-quality CBV maps and signal intensity-time curves were achieved in all patients, and quantitative evaluations were equal or superior to those reported for adults. No significant differences (P ≥ .05) were identified among the higher-flow-rate groups in the quantitative data. CONCLUSIONS A custom administration of a standard dose of gadobutrol allows safe and high-quality DSC MR perfusion imaging in children.
Collapse
Affiliation(s)
- S Gaudino
- From the Operative Unit Radiodiagnostica e Neuroradiologia (S.G.,A.B., E.R., E.L., A.I., A.R., C.C.), Dipartimento di Diagnostica per Immagini, Radioterapia Oncologica e Ematologia
| | - M Martucci
- Operative Unit di Neuroradiologia (M.M.), Azienda Ospedaliera, Università di Padova, Padova, Italy
| | - A Botto
- From the Operative Unit Radiodiagnostica e Neuroradiologia (S.G.,A.B., E.R., E.L., A.I., A.R., C.C.), Dipartimento di Diagnostica per Immagini, Radioterapia Oncologica e Ematologia
| | - E Ruberto
- From the Operative Unit Radiodiagnostica e Neuroradiologia (S.G.,A.B., E.R., E.L., A.I., A.R., C.C.), Dipartimento di Diagnostica per Immagini, Radioterapia Oncologica e Ematologia
- Istituto di Radiologia (E.R., E.L., A.R., C.C), Fondazione Policlinico Universitario A. Gemelli Istituto di Ricovero e Cura a Carattere Scientifico, Rome, Italy
- Università Cattolica del Sacro Cuore (E.R., E.L., A.R., C.C), Milan, Italy
| | - E Leone
- From the Operative Unit Radiodiagnostica e Neuroradiologia (S.G.,A.B., E.R., E.L., A.I., A.R., C.C.), Dipartimento di Diagnostica per Immagini, Radioterapia Oncologica e Ematologia
- Istituto di Radiologia (E.R., E.L., A.R., C.C), Fondazione Policlinico Universitario A. Gemelli Istituto di Ricovero e Cura a Carattere Scientifico, Rome, Italy
- Università Cattolica del Sacro Cuore (E.R., E.L., A.R., C.C), Milan, Italy
| | - A Infante
- From the Operative Unit Radiodiagnostica e Neuroradiologia (S.G.,A.B., E.R., E.L., A.I., A.R., C.C.), Dipartimento di Diagnostica per Immagini, Radioterapia Oncologica e Ematologia
| | - A Ramaglia
- From the Operative Unit Radiodiagnostica e Neuroradiologia (S.G.,A.B., E.R., E.L., A.I., A.R., C.C.), Dipartimento di Diagnostica per Immagini, Radioterapia Oncologica e Ematologia
- Istituto di Radiologia (E.R., E.L., A.R., C.C), Fondazione Policlinico Universitario A. Gemelli Istituto di Ricovero e Cura a Carattere Scientifico, Rome, Italy
- Università Cattolica del Sacro Cuore (E.R., E.L., A.R., C.C), Milan, Italy
| | - M Caldarelli
- Neurochirurgia infantile (M.C., P.F.), Fondazione Policlinico Universitario Agostino Gemelli Istituto di Ricovero e Cura a Carattere, Rome, Italy
| | - P Frassanito
- Neurochirurgia infantile (M.C., P.F.), Fondazione Policlinico Universitario Agostino Gemelli Istituto di Ricovero e Cura a Carattere, Rome, Italy
| | - F M Triulzi
- Neuroradiology Unit (F.M.T.), Foundation Istituto di Ricovero e Cura a Carattere Scientifico, Cà Granda Ospedale Maggiore Policlinico, Milan, Italy
- Department of Pathophysiology and Transplantation (F.M.T.), University of Milan, Milan, Italy
| | - C Colosimo
- From the Operative Unit Radiodiagnostica e Neuroradiologia (S.G.,A.B., E.R., E.L., A.I., A.R., C.C.), Dipartimento di Diagnostica per Immagini, Radioterapia Oncologica e Ematologia
- Istituto di Radiologia (E.R., E.L., A.R., C.C), Fondazione Policlinico Universitario A. Gemelli Istituto di Ricovero e Cura a Carattere Scientifico, Rome, Italy
- Università Cattolica del Sacro Cuore (E.R., E.L., A.R., C.C), Milan, Italy
| |
Collapse
|
19
|
Clinical Applications of Quantitative 3-Dimensional MRI Analysis for Pediatric Embryonal Brain Tumors. Int J Radiat Oncol Biol Phys 2018; 102:744-756. [DOI: 10.1016/j.ijrobp.2018.05.077] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2017] [Revised: 05/22/2018] [Accepted: 05/28/2018] [Indexed: 12/23/2022]
|
20
|
Dangouloff-Ros V, Varlet P, Levy R, Beccaria K, Puget S, Dufour C, Boddaert N. Imaging features of medulloblastoma: Conventional imaging, diffusion-weighted imaging, perfusion-weighted imaging, and spectroscopy: From general features to subtypes and characteristics. Neurochirurgie 2018; 67:6-13. [PMID: 30170827 DOI: 10.1016/j.neuchi.2017.10.003] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2017] [Revised: 09/13/2017] [Accepted: 10/29/2017] [Indexed: 12/13/2022]
Abstract
Medulloblastoma is a frequent high-grade neoplasm among pediatric brain tumours. Its classical imaging features are a midline tumour growing into the fourth ventricle, hyperdense on CT-scan, displaying a hypersignal when using diffusion-weighted imaging, with a variable contrast enhancement. Nevertheless, atypical imaging features have been widely reported, varying according to the age of the patient, and histopathological subtype. In this study, we review the classical and atypical imaging features of medulloblastomas, with emphasis on advanced MRI techniques, histopathological and molecular subtypes and characteristics, and follow-up modalities.
Collapse
Affiliation(s)
- V Dangouloff-Ros
- Department of pediatric radiology, hôpital Necker-Enfants-Malades, AP-HP, 149, rue de Sèvres, 75105 Paris, France; Inserm U1000, 149, rue de Sèvres, 75015 Paris, France; University René-Descartes, PRES-Sorbonne-Paris-Cité, 12, rue de l'École-de-Médecine, Paris, France.
| | - P Varlet
- University René-Descartes, PRES-Sorbonne-Paris-Cité, 12, rue de l'École-de-Médecine, Paris, France; Department of neuropathology, centre hospitalier Sainte-Anne, 1, rue Cabanis, 75014 Paris, France
| | - R Levy
- Department of pediatric radiology, hôpital Necker-Enfants-Malades, AP-HP, 149, rue de Sèvres, 75105 Paris, France; Inserm U1000, 149, rue de Sèvres, 75015 Paris, France; University René-Descartes, PRES-Sorbonne-Paris-Cité, 12, rue de l'École-de-Médecine, Paris, France
| | - K Beccaria
- University René-Descartes, PRES-Sorbonne-Paris-Cité, 12, rue de l'École-de-Médecine, Paris, France; Department of pediatric neurosurgery, hôpital Necker-Enfants-Malades, AP-HP, 149, rue de Sèvres, 75105 Paris, France
| | - S Puget
- University René-Descartes, PRES-Sorbonne-Paris-Cité, 12, rue de l'École-de-Médecine, Paris, France; Department of pediatric neurosurgery, hôpital Necker-Enfants-Malades, AP-HP, 149, rue de Sèvres, 75105 Paris, France
| | - C Dufour
- Department of pediatric and adolescent oncology, Gustave-Roussy Institute, 114, rue Édouard-Vaillant, 94800 Villejuif, France
| | - N Boddaert
- Department of pediatric radiology, hôpital Necker-Enfants-Malades, AP-HP, 149, rue de Sèvres, 75105 Paris, France; Inserm U1000, 149, rue de Sèvres, 75015 Paris, France; University René-Descartes, PRES-Sorbonne-Paris-Cité, 12, rue de l'École-de-Médecine, Paris, France; UMR 1163, institut Imagine, 24, boulevard du Montparnasse, 75015 Paris, France
| |
Collapse
|
21
|
Abrigo JM, Fountain DM, Provenzale JM, Law EK, Kwong JSW, Hart MG, Tam WWS. Magnetic resonance perfusion for differentiating low-grade from high-grade gliomas at first presentation. Cochrane Database Syst Rev 2018; 1:CD011551. [PMID: 29357120 PMCID: PMC6491341 DOI: 10.1002/14651858.cd011551.pub2] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
BACKGROUND Gliomas are the most common primary brain tumour. They are graded using the WHO classification system, with Grade II-IV astrocytomas, oligodendrogliomas and oligoastrocytomas. Low-grade gliomas (LGGs) are WHO Grade II infiltrative brain tumours that typically appear solid and non-enhancing on magnetic resonance imaging (MRI) scans. People with LGG often have little or no neurologic deficit, so may opt for a watch-and-wait-approach over surgical resection, radiotherapy or both, as surgery can result in early neurologic disability. Occasionally, high-grade gliomas (HGGs, WHO Grade III and IV) may have the same MRI appearance as LGGs. Taking a watch-and-wait approach could be detrimental for the patient if the tumour progresses quickly. Advanced imaging techniques are increasingly used in clinical practice to predict the grade of the tumour and to aid clinical decision of when to intervene surgically. One such advanced imaging technique is magnetic resonance (MR) perfusion, which detects abnormal haemodynamic changes related to increased angiogenesis and vascular permeability, or "leakiness" that occur with aggressive tumour histology. These are reflected by changes in cerebral blood volume (CBV) expressed as rCBV (ratio of tumoural CBV to normal appearing white matter CBV) and permeability, measured by Ktrans. OBJECTIVES To determine the diagnostic test accuracy of MR perfusion for identifying patients with primary solid and non-enhancing LGGs (WHO Grade II) at first presentation in children and adults. In performing the quantitative analysis for this review, patients with LGGs were considered disease positive while patients with HGGs were considered disease negative.To determine what clinical features and methodological features affect the accuracy of MR perfusion. SEARCH METHODS Our search strategy used two concepts: (1) glioma and the various histologies of interest, and (2) MR perfusion. We used structured search strategies appropriate for each database searched, which included: MEDLINE (Ovid SP), Embase (Ovid SP), and Web of Science Core Collection (Science Citation Index Expanded and Conference Proceedings Citation Index). The most recent search for this review was run on 9 November 2016.We also identified 'grey literature' from online records of conference proceedings from the American College of Radiology, European Society of Radiology, American Society of Neuroradiology and European Society of Neuroradiology in the last 20 years. SELECTION CRITERIA The titles and abstracts from the search results were screened to obtain full-text articles for inclusion or exclusion. We contacted authors to clarify or obtain missing/unpublished data.We included cross-sectional studies that performed dynamic susceptibility (DSC) or dynamic contrast-enhanced (DCE) MR perfusion or both of untreated LGGs and HGGs, and where rCBV and/or Ktrans values were reported. We selected participants with solid and non-enhancing gliomas who underwent MR perfusion within two months prior to histological confirmation. We excluded studies on participants who received radiation or chemotherapy before MR perfusion, or those without histologic confirmation. DATA COLLECTION AND ANALYSIS Two review authors extracted information on study characteristics and data, and assessed the methodological quality using the Quality Assessment of Diagnostic Accuracy Studies (QUADAS-2) tool. We present a summary of the study characteristics and QUADAS-2 results, and rate studies as good quality when they have low risk of bias in the domains of reference standard of tissue diagnosis and flow and timing between MR perfusion and tissue diagnosis.In the quantitative analysis, LGGs were considered disease positive, while HGGs were disease negative. The sensitivity refers to the proportion of LGGs detected by MR perfusion, and specificity as the proportion of detected HGGs. We constructed two-by-two tables with true positives and false negatives as the number of correctly and incorrectly diagnosed LGG, respectively, while true negatives and false positives are the number of correctly and incorrectly diagnosed HGG, respectively.Meta-analysis was performed on studies with two-by-two tables, with further sensitivity analysis using good quality studies. Limited data precluded regression analysis to explore heterogeneity but subgroup analysis was performed on tumour histology groups. MAIN RESULTS Seven studies with small sample sizes (4 to 48) met our inclusion criteria. These were mostly conducted in university hospitals and mostly recruited adult patients. All studies performed DSC MR perfusion and described heterogeneous acquisition and post-processing methods. Only one study performed DCE MR perfusion, precluding quantitative analysis.Using patient-level data allowed selection of individual participants relevant to the review, with generally low risks of bias for the participant selection, reference standard and flow and timing domains. Most studies did not use a pre-specified threshold, which was considered a significant source of bias, however this did not affect quantitative analysis as we adopted a common rCBV threshold of 1.75 for the review. Concerns regarding applicability were low.From published and unpublished data, 115 participants were selected and included in the meta-analysis. Average rCBV (range) of 83 LGGs and 32 HGGs were 1.29 (0.01 to 5.10) and 1.89 (0.30 to 6.51), respectively. Using the widely accepted rCBV threshold of <1.75 to differentiate LGG from HGG, the summary sensitivity/specificity estimates were 0.83 (95% CI 0.66 to 0.93)/0.48 (95% CI 0.09 to 0.90). Sensitivity analysis using five good quality studies yielded sensitivity/specificity of 0.80 (95% CI 0.61 to 0.91)/0.67 (95% CI 0.07 to 0.98). Subgroup analysis for tumour histology showed sensitivity/specificity of 0.92 (95% CI 0.55 to 0.99)/0.42 (95% CI 0.02 to 0.95) in astrocytomas (6 studies, 55 participants) and 0.77 (95% CI 0.46 to 0.93)/0.53 (95% CI 0.14 to 0.88) in oligodendrogliomas+oligoastrocytomas (6 studies, 56 participants). Data were too sparse to investigate any differences across subgroups. AUTHORS' CONCLUSIONS The limited available evidence precludes reliable estimation of the performance of DSC MR perfusion-derived rCBV for the identification of grade in untreated solid and non-enhancing LGG from that of HGG. Pooled data yielded a wide range of estimates for both sensitivity (range 66% to 93% for detection of LGGs) and specificity (range 9% to 90% for detection of HGGs). Other clinical and methodological features affecting accuracy of the technique could not be determined from the limited data. A larger sample size of both LGG and HGG, preferably using a standardised scanning approach and with an updated reference standard incorporating molecular profiles, is required for a definite conclusion.
Collapse
Affiliation(s)
- Jill M Abrigo
- The Chinese University of Hong KongDepartment of Imaging and Interventional RadiologyPrince of Wales Hospital30 Ngan Shing StShatinHong Kong
| | - Daniel M Fountain
- Addenbrookes HospitalAcademic Division of Neurosurgery, Department of Clinical NeurosciencesBox 167CambridgeUKCB2 0QQ
| | - James M Provenzale
- Duke University Medical CenterDepartment of RadiologyBox 3808DurhamNCUSA27710
| | - Eric K Law
- The Chinese University of Hong KongDepartment of Imaging and Interventional RadiologyPrince of Wales Hospital30 Ngan Shing StShatinHong Kong
| | - Joey SW Kwong
- Jockey Club School of Public Health and Primary Care, Faculty of Medicine, The Chinese University of Hong KongDepartment of Epidemiology and BiostatisticsPrince of Wales HospitalShatinN.T.Hong Kong
| | - Michael G Hart
- Addenbrookes HospitalAcademic Division of Neurosurgery, Department of Clinical NeurosciencesBox 167CambridgeUKCB2 0QQ
| | - Wilson Wai San Tam
- National University of Singapore, National University Health SystemAlice Lee Centre for Nursing StudiesSingaporeSingapore
| | | |
Collapse
|
22
|
Vajapeyam S, Brown D, Johnston PR, Ricci KI, Kieran MW, Lidov HGW, Poussaint TY. Multiparametric Analysis of Permeability and ADC Histogram Metrics for Classification of Pediatric Brain Tumors by Tumor Grade. AJNR Am J Neuroradiol 2018; 39:552-557. [PMID: 29301780 DOI: 10.3174/ajnr.a5502] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2017] [Accepted: 10/30/2017] [Indexed: 12/22/2022]
Abstract
BACKGROUND AND PURPOSE Accurate tumor grading is essential for treatment planning of pediatric brain tumors. We hypothesized that multiparametric analyses of a combination of permeability metrics and ADC histogram metrics would differentiate high- and low-grade tumors with high accuracy. MATERIALS AND METHODS DTI and dynamic contrast-enhanced MR imaging using T1-mapping with flip angles of 2°, 5°, 10°, and 15°, followed by a 0.1-mmol/kg body weight gadolinium-based bolus was performed on all patients in addition to standard MR imaging. Permeability data were processed and transfer constant from the blood plasma into the extracellular extravascular space, rate constant from the extracellular extravascular space back into blood plasma, extravascular extracellular volume fraction, and fractional blood plasma volume were calculated from 3D tumor volumes. Apparent diffusion coefficient histogram metrics were calculated for 3 separate tumor volumes derived from T2-FLAIR sequences, T1 contrast-enhanced sequences, and permeability maps, respectively. RESULTS Results from 41 patients (0.3-16.76 years of age; mean, 6.22 years) with newly diagnosed contrast-enhancing brain tumors (16 low-grade; 25 high-grade) were included in the institutional review board-approved retrospective analysis. Wilcoxon tests showed a higher transfer constant from blood plasma into extracellular extravascular space and rate constant from extracellular extravascular space back into blood plasma, and lower extracellular extravascular volume fraction (P < .001) in high-grade tumors. The mean ADCs of FLAIR and enhancing tumor volumes were significantly lower in high-grade tumors (P < .001). ROC analysis showed that a combination of extravascular volume fraction and mean ADC of FLAIR volume differentiated high- and low-grade tumors with high accuracy (area under receiver operating characteristic curve = 0.918). CONCLUSIONS ADC histogram metrics combined with permeability metrics differentiate low- and high-grade pediatric brain tumors with high accuracy.
Collapse
Affiliation(s)
- S Vajapeyam
- From the Departments of Radiology (S.V., D.B., P.R.J., T.Y.P.) .,Harvard Medical School (S.V., M.W.K., H.G.W.L., T.Y.P.), Boston, Massachusetts
| | - D Brown
- From the Departments of Radiology (S.V., D.B., P.R.J., T.Y.P.)
| | - P R Johnston
- From the Departments of Radiology (S.V., D.B., P.R.J., T.Y.P.)
| | - K I Ricci
- Cancer Center (K.I.R.), Massachusetts General Hospital, Boston, Massachusetts
| | - M W Kieran
- Division of Pediatric Oncology (M.W.K.), Dana-Farber Boston Children's Cancer and Blood Disorders Center, Boston, Massachusetts.,Harvard Medical School (S.V., M.W.K., H.G.W.L., T.Y.P.), Boston, Massachusetts
| | - H G W Lidov
- Pathology (H.G.W.L.), Boston Children's Hospital, Boston, Massachusetts.,Harvard Medical School (S.V., M.W.K., H.G.W.L., T.Y.P.), Boston, Massachusetts
| | - T Y Poussaint
- From the Departments of Radiology (S.V., D.B., P.R.J., T.Y.P.).,Harvard Medical School (S.V., M.W.K., H.G.W.L., T.Y.P.), Boston, Massachusetts
| |
Collapse
|
23
|
Noninvasive Grading of Glioma Tumor Using Magnetic Resonance Imaging with Convolutional Neural Networks. APPLIED SCIENCES-BASEL 2017. [DOI: 10.3390/app8010027] [Citation(s) in RCA: 63] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
|
24
|
Vajapeyam S, Stamoulis C, Ricci K, Kieran M, Poussaint TY. Automated Processing of Dynamic Contrast-Enhanced MRI: Correlation of Advanced Pharmacokinetic Metrics with Tumor Grade in Pediatric Brain Tumors. AJNR Am J Neuroradiol 2016; 38:170-175. [PMID: 27633807 DOI: 10.3174/ajnr.a4949] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2016] [Accepted: 08/01/2016] [Indexed: 12/29/2022]
Abstract
BACKGROUND AND PURPOSE Pharmacokinetic parameters from dynamic contrast-enhanced MR imaging have proved useful for differentiating brain tumor grades in adults. In this study, we retrospectively reviewed dynamic contrast-enhanced perfusion data from children with newly diagnosed brain tumors and analyzed the pharmacokinetic parameters correlating with tumor grade. MATERIALS AND METHODS Dynamic contrast-enhanced MR imaging data from 38 patients were analyzed by using commercially available software. Subjects were categorized into 2 groups based on pathologic analyses consisting of low-grade (World Health Organization I and II) and high-grade (World Health Organization III and IV) tumors. Pharmacokinetic parameters were compared between the 2 groups by using linear regression models. For parameters that were statistically distinct between the 2 groups, sensitivity and specificity were also estimated. RESULTS Eighteen tumors were classified as low-grade, and 20, as high-grade. Transfer constant from the blood plasma into the extracellular extravascular space (Ktrans), rate constant from extracellular extravascular space back into blood plasma (Kep), and extracellular extravascular volume fraction (Ve) were all significantly correlated with tumor grade; high-grade tumors showed higher Ktrans, higher Kep, and lower Ve. Although all 3 parameters had high specificity (range, 82%-100%), Kep had the highest specificity for both grades. Optimal sensitivity was achieved for Ve, with a combined sensitivity of 76% (compared with 71% for Ktrans and Kep). CONCLUSIONS Pharmacokinetic parameters derived from dynamic contrast-enhanced MR imaging can effectively discriminate low- and high-grade pediatric brain tumors.
Collapse
Affiliation(s)
- S Vajapeyam
- From the Departments of Radiology (S.V., C.S., T.Y.P.) .,Harvard Medical School (S.V., C.S., M.K., T.Y.P.), Boston, Massachusetts
| | - C Stamoulis
- From the Departments of Radiology (S.V., C.S., T.Y.P.).,Neurology (C.S.), Boston Children's Hospital, Boston, Massachusetts.,Harvard Medical School (S.V., C.S., M.K., T.Y.P.), Boston, Massachusetts
| | - K Ricci
- Cancer Center (K.R.), Massachusetts General Hospital, Boston, Massachusetts
| | - M Kieran
- Department of Pediatric Oncology (M.K.), Dana-Farber Cancer Center, Boston, Massachusetts.,Harvard Medical School (S.V., C.S., M.K., T.Y.P.), Boston, Massachusetts
| | - T Young Poussaint
- From the Departments of Radiology (S.V., C.S., T.Y.P.).,Harvard Medical School (S.V., C.S., M.K., T.Y.P.), Boston, Massachusetts
| |
Collapse
|