Abdominal lymph node size in children at computed tomography

Background: Lymph node enlargement is commonly used to indicate abnormality. Objective: To evaluate the normal size and prevalence of abdominal lymph nodes in children at CT. Materials and methods: In this retrospective study, we included a total of 152 children ages 1–17 years who underwent abdominal CT examination after high-energy trauma. We measured abdominal lymph nodes in five lymph node stations (inguinal, iliac, para-aortic, hepatic and mesenteric). For the largest lymph node in each level, we measured long- and short-axis diameters in both the axial and coronal planes. We then calculated distribution parameters, correlation coefficients between lymph node size and age, and reference intervals. Results: The prevalence of detectable lymph nodes was high for the inguinal (100%), iliac (98%), para-aortic (97%) and mesenteric (99%) stations and lower for the hepatic station (32%). Lymph node size showed small to medium significant correlations (ranging from 0.21 to 0.50) with age. When applying the Lugano criteria and RECIST (Response Criteria in Solid Tumors), 29 children (19%) would have had one or more enlarged abdominal lymph nodes. Conclusion: The results of this study provide normative data of abdominal lymph node size in children. The current adult guidelines for enlarged lymph nodes seem adequate for most children with the exception of young adolescents, in which larger lymph nodes were relatively common, particularly in the inguinal region

Whole-body MRI versus an [18F]FDG-PET/CT-based reference standard for early response assessment and restaging of paediatric Hodgkin’s lymphoma: a prospective multicentre study

Child; Diffusion magnetic resonance imaging; Whole-body imagingNiño; Imágenes por resonancia magnética de difusión; Imágenes de cuerpo enteroNen; Imatge per ressonància magnètica de difusió; Imatge de cos sencerObjectives To compare WB-MRI with an [18F]FDG-PET/CT-based reference for early response assessment and restaging in children with Hodgkin’s lymphoma (HL). Methods Fifty-one children (ages 10–17) with HL were included in this prospective, multicentre study. All participants underwent WB-MRI and [18F]FDG-PET/CT at early response assessment. Thirteen of the 51 patients also underwent both WB-MRI and [18F]FDG-PET/CT at restaging. Two radiologists independently evaluated all WB-MR images in two separate readings: without and with DWI. The [18F]FDG-PET/CT examinations were evaluated by a nuclear medicine physician. An expert panel assessed all discrepancies between WB-MRI and [18F]FDG-PET/CT to derive the [18F]FDG-PET/CT-based reference standard. Inter-observer agreement for WB-MRI was calculated using kappa statistics. Concordance, PPV, NPV, sensitivity and specificity for a correct assessment of the response between WB-MRI and the reference standard were calculated for both nodal and extra-nodal disease presence and total response evaluation. Results Inter-observer agreement of WB-MRI including DWI between both readers was moderate (κ 0.46–0.60). For early response assessment, WB-MRI DWI agreed with the reference standard in 33/51 patients (65%, 95% CI 51–77%) versus 15/51 (29%, 95% CI 19–43%) for WB-MRI without DWI. For restaging, WB-MRI including DWI agreed with the reference standard in 9/13 patients (69%, 95% CI 42–87%) versus 5/13 patients (38%, 95% CI 18–64%) for WB-MRI without DWI. Conclusions The addition of DWI to the WB-MRI protocol in early response assessment and restaging of paediatric HL improved agreement with the [18F]FDG-PET/CT-based reference standard. However, WB-MRI remained discordant in 30% of the patients compared to standard imaging for assessing residual disease presence.This project was financially supported by the Stichting Kinderen Kankervrij (KiKa, project number 87). The data collection, analysis and interpretation of data, the writing of the paper and the decision to submit were not influenced by KiKa

A meta-analysis on the diagnostic performance of whole-body MRI for the initial staging of Hodgkin lymphoma in children and adults using FDG-PET/CT as a reference standard

Background: Staging of Hodgkin lymphoma is important for determining prognosis and treatment planning. The current gold standard is FDG-PET/CT, but WB-MRI could be a radiation free alternative. Objective: A meta-analysis of all published data on the diagnostic performance of WB-MRI for the initial staging of Hodgkin lymphoma using FDG-PET/CT as a reference standard. Evidence Acquisition: Both the PubMed/MEDLINE and EMBASE databases were systematically searched (updated until March 14, 2023) for studies that compared WB-MRI with FDG-PET/CT for staging Hodgkin lymphoma. The “quality assessment of diagnostic accuracy studies” tool (QUADAS-2) was used to assess methodological quality. Pooled staging accuracy, sensitivity and specificity of WB-MRI compared to FDG-PET/CT was calculated for determining stage and for both nodal and extra-nodal staging. A sensitivity analysis for children and adults was performed. Evidence Synthesis: A total of nine studies with a combined total of 297 Hodgkin lymphoma patients were included. Pooled sensitivity and specificity for nodal staging were 94% (95%CI 0.92–0.96) and 99% (95%CI 0.98–1.00) respectively. For extra-nodal staging sensitivity and specificity were 90% (95%CI 0.74–0.96) and 100% (95%CI 0.99–1.00). For disease stage, the pooled accuracy was 92% for pediatric studies (95%CI 0.86–0.96), 94% for adult studies (95%CI 0.87–0.97) and 92% (95%CI 0.87–0.96) for all studies combined. Conclusion: When using FDG-PET/CT as a reference standard, WB-MRI shows high sensitivity and specificity for both nodal and extra-nodal staging and for determining disease stage both in children and adults. Clinical Impact: WB-MRI could be used as a good radiation-free alternative for FDG-PET/CT in Hodgkin lymphoma staging

Whole-body MRI versus an [F-18]FDG-PET/CT-based reference standard for early response assessment and restaging of paediatric Hodgkin's lymphoma:a prospective multicentre study

Objectives To compare WB-MRI with an [F-18]FDG-PET/CT-based reference for early response assessment and restaging in children with Hodgkin's lymphoma (HL). Methods Fifty-one children (ages 10-17) with HL were included in this prospective, multicentre study. All participants underwent WB-MRI and [F-18]FDG-PET/CT at early response assessment. Thirteen of the 51 patients also underwent both WB-MRI and [F-18]FDG-PET/CT at restaging. Two radiologists independently evaluated all WB-MR images in two separate readings: without and with DWI. The [F-18]FDG-PET/CT examinations were evaluated by a nuclear medicine physician. An expert panel assessed all discrepancies between WB-MRI and [F-18]FDG-PET/CT to derive the [F-18]FDG-PET/CT-based reference standard. Inter-observer agreement for WB-MRI was calculated using kappa statistics. Concordance, PPV, NPV, sensitivity and specificity for a correct assessment of the response between WB-MRI and the reference standard were calculated for both nodal and extra-nodal disease presence and total response evaluation. Results Inter-observer agreement of WB-MRI including DWI between both readers was moderate (kappa 0.46-0.60). For early response assessment, WB-MRI DWI agreed with the reference standard in 33/51 patients (65%, 95% CI 51-77%) versus 15/51 (29%, 95% CI 19-43%) for WB-MRI without DWI. For restaging, WB-MRI including DWI agreed with the reference standard in 9/13 patients (69%, 95% CI 42-87%) versus 5/13 patients (38%, 95% CI 18-64%) for WB-MRI without DWI. Conclusions The addition of DWI to the WB-MRI protocol in early response assessment and restaging of paediatric HL improved agreement with the [F-18]FDG-PET/CT-based reference standard. However, WB-MRI remained discordant in 30% of the patients compared to standard imaging for assessing residual disease presence

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

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 (kappa= 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

Pediatric body composition based on automatic segmentation of computed tomography scans: a pilot study

Background: Body composition during childhood may predispose to negative health outcomes later in life. Automatic segmentation may assist in quantifying pediatric body composition in children. Objective: To evaluate automatic segmentation for body composition on pediatric computed tomography (CT) scans and to provide normative data on muscle and fat areas throughout childhood using automatic segmentation. Materials and methods: In this pilot study, 537 children (ages 1–17 years) who underwent abdominal CT after high-energy trauma at a Dutch tertiary center (2002–2019) were retrospectively identified. Of these, the CT images of 493 children (66% boys) were used to establish normative data. Muscle (psoas, paraspinal and abdominal wall) and fat (subcutaneous and visceral) areas were measured at the third lumbar vertebral (L3) level by automatic segmentation. A representative subset of 52 scans was also manually segmented to evaluate the performance of automatic segmentation. Results: For manually-segmented versus automatically-segmented areas (52 scans), mean Dice coefficients were high for muscle (0.87–0.90) and subcutaneous fat (0.88), but lower for visceral fat (0.60). In the control group, muscle area was comparable for both sexes until the age of 13 years, whereafter, boys developed relatively more muscle. From a young age, boys were more prone to visceral fat storage than girls. Overall, boys had significantly higher visceral-to-subcutaneous fat ratios (median 1.1 vs. 0.6, P<0.01) and girls higher fat-to-muscle ratios (median 1.0 vs. 0.7, P<0.01). Conclusion: Automatic segmentation of L3-level muscle and fat areas allows for accurate quantification of pediatric body composition. Using automatic segmentation, the development in muscle and fat distribution during childhood (in otherwise healthy) Dutch children was demonstrated

Whole-body MRI in paediatric Hodgkin lymphoma

Lymphomas (lymph node cancer) are the third most common form of cancer in children. About a third of the lymphomas are Hodgkin lymphomas. Medical imaging plays an important role in determining disease progression (staging), assessment of response to therapy, and follow-up of children with Hodgkin lymphoma. Over the past few years, the use of imaging studies in Hodgkin lymphoma has shifted from Computed Tomography (CT) to the addition of Positron Emission Tomography (PET) and most recently, whole-body Magnetic Resonance Imaging (MRI). This thesis focuses on determining the diagnostic accuracy of whole-body MRI for staging, early assessment of response to therapy and assessment of remission at the end of therapy in children with Hodgkin lymphoma. In addition, normal values of lymph nodes in children are investigated. In summary, the studies show that data on the normal size of the lymph nodes by age is very important for a correct diagnosis of pathological lymph nodes. This is especially relevant in children. In addition, the studies presented in this thesis show that it is still challenging to determine the optimal role of whole-body MRI in imaging protocols for paediatric Hodgkin lymphoma. The results indicate that whole-body MRI is a very suitable radiation-free alternative to anatomical imaging by CT. In addition, this thesis shows that whole-body MRI can be a good alternative to FDG-PET/CT for the staging of Hodgkin lymphoma in children. Whole-body MRI (including visual assessment of DWI), however, did not correlate sufficiently with FDG-PET/CT for (early) response assessment

Measurements of cervical lymph nodes in children on computed tomography

Background: No normal measurements or specific size criteria have been described for cervical lymph nodes in children. Objective: To determine the normal measurements of cervical lymph nodes in children on CT. Materials and methods: We included 142 children (ages 1–17 years) who underwent cervical CT examination after high-energy trauma. We evaluated axial and coronal 2-mm reconstructions for lymph nodes at six cervical levels. For the largest lymph node at each level, we measured diameters in both the long and short axial axes and the long coronal axis. Results: A total of 733 lymph nodes were measured in 142 children (62% boys, 38% girls). The greatest measured diameters were 14 mm for the short axis in the axial plane, 24 mm for the long axis in the axial plane and 28 mm for the long axis in the coronal plane. The Pearson correlation coefficient for age and lymph node size at Levels IV–VI was in the range of 0.19–0.47. Conclusion: Lymph nodes with an axial short-axis diameter exceeding 15 mm for Level II and 10 mm for all other cervical levels are uncommon in otherwise healthy children

Fresh and Frozen-Thawed Embryo Transfer Compared to Natural Conception: Differences in Perinatal Outcome

Background/Aim: To compare the pregnancy outcome of singletons conceived after transfer of cryopreserved and thawed embryos (frozen embryo transfer [FET]) to singletons conceived after fresh embryo transfer (fresh ET) and natural conceived singletons. Methods: Using a retrospective data analysis on a study population consisting of 1,261 singletons born after FET and 2,519 singletons born after fresh ET between 2006 and 2015. The control group consisted of singletons born after natural conception. Main outcome measures consisted of birth weight (in grams), gestational age, preterm birth (<37 weeks of gestation), being large for gestational age (LGA, above 90th weight percentile adjusted for gestational age) and Apgar scores. Results: Babies born after FET had an increased risk of high birth weight (adjusted OR [AOR]) 2.92; 1.503-3.482) and being LGA (AOR fresh ET vs. FET 1.47; 1.210-1.787) compared to singletons born after fresh ET, as well as higher birth weights compared to natural conceived children. Conclusions: Singletons born after FET have a higher risk of high birth weight and being LGA compared to singletons after fresh ET and compared to natural conceived singletons. We assume that the freezing process might be the underlying cause