RESUMEN
BACKGROUND: Hip involvement predicts severe disease in juvenile idiopathic arthritis (JIA) and is accurately assessed by MRI. However, a child-specific hip MRI scoring system has not been validated. OBJECTIVE: To test the intra- and interobserver agreement of several MRI markers for active and chronic hip changes in children and young adults with JIA and to examine the precision of measurements commonly used for the assessment of growth abnormalities. MATERIALS AND METHODS: Hip MRIs from 60 consecutive children, adolescents and young adults with JIA were scored independently by two sets of radiologists. One set scored the same MRIs twice. Features of active and chronic changes, growth abnormalities and secondary post-inflammatory changes were scored. We used kappa statistics to analyze inter- and intraobserver agreement for categorical variables and a Bland-Altman approach to test the precision of continuous variables. RESULTS: Among active changes, there was good intra- and interobserver agreement for grading overall inflammation (kappa 0.6-0.7). Synovial enhancement showed a good intraobserver agreement (kappa 0.7-0.8), while the interobserver agreement was moderate (kappa 0.4-0.5). Regarding acetabular erosions on a 0-3 scale, the intraobserver agreement was 0.6 for the right hip and 0.7 for the left hip, while the interobserver agreement was 0.6 for both hips. Measurements of joint space width, caput-collum-diaphyseal angle, femoral neck-head length, femoral width and trochanteric distance were imprecise. CONCLUSION: We identified a set of MRI markers for active and chronic changes in JIA and suggest that the more robust markers be included in future studies addressing clinical validity and long-term patient outcomes.
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Artritis Juvenil , Adulto Joven , Humanos , Adolescente , Artritis Juvenil/patología , Imagen por Resonancia Magnética/métodos , Articulación de la Rodilla/patología , Reproducibilidad de los Resultados , Índice de Severidad de la EnfermedadRESUMEN
BACKGROUND: Whole-body magnetic resonance imaging (MRI) is increasingly being used in children, however, to date there are no studies addressing the reliability of the findings. OBJECTIVE: To examine intra- and interobserver reliability of a scoring system for assessment of high signal areas within the bone marrow, as visualized on T2-weighted, fat-saturated images. MATERIALS AND METHODS: Ninety-six whole-body MRIs (1.5 T) in 78 healthy volunteers (mean age: 11.5 years) and 18 children with chronic nonbacterial osteomyelitis (mean age: 12.4 years) were included. Coronal water-only Dixon T2-weighted images were used to score the left lower extremity/pelvis for high signal intensity areas, intensity (0-2 scale), extension (0-4 scale) and shape and contour in a blinded fashion by two pairs of radiologists. RESULTS: For the pelvis, grading of bone marrow signal showed moderate to good intra- and interobserver agreement with kappa values of 0.51-0.94 and 0.41-0.87, respectively. Corresponding figures for the femur were 0.61-0.68 within and 0.32-0.61 between observers, and for the tibia 0.60-0.72 and 0.51-0.73. Agreement for assessing extension was moderate to good both within and between observers for the pelvis (k = 0.52-0.85 and 0.35-0.80), for the femur (0.52-0.67 and 0.51-0.60) and for the tibia (k = 0.59-0.69 and 0.47-0.63) except for the femur metaphysis/diaphysis, with interobserver kappa values of 0.29-0.30. Scoring of shape was moderate to good within observers, but in general poorer between observers, with kappa values of 0.40-0.73 and 0.18-0.69, respectively. For contour, the corresponding figures were 0.35-0.62 and 0.09-0.54, respectively. CONCLUSION: MRI grading of intensity and extension of high signal intensity areas within the bone marrow of pelvis and lower limb performs well and thus can be used interchangeably by different observers, while assessment of shape and contour is reliable for the same observer but is less reliable between observers. This should be considered when performing clinical trials.
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Médula Ósea , Imagen por Resonancia Magnética , Médula Ósea/diagnóstico por imagen , Niño , Fémur , Humanos , Imagen por Resonancia Magnética/métodos , Variaciones Dependientes del Observador , Reproducibilidad de los Resultados , Imagen de Cuerpo EnteroRESUMEN
BACKGROUND: Manual assessment of bone marrow signal is time-consuming and requires meticulous standardisation to secure adequate precision of findings. OBJECTIVE: We examined the feasibility of using deep learning for automated segmentation of bone marrow signal in children and adolescents. MATERIALS AND METHODS: We selected knee images from 95 whole-body MRI examinations of healthy individuals and of children with chronic non-bacterial osteomyelitis, ages 6-18 years, in a longitudinal prospective multi-centre study cohort. Bone marrow signal on T2-weighted Dixon water-only images was divided into three color-coded intensity-levels: 1 = slightly increased; 2 = mildly increased; 3 = moderately to highly increased, up to fluid-like signal. We trained a convolutional neural network on 85 examinations to perform bone marrow segmentation. Four readers manually segmented a test set of 10 examinations and calculated ground truth using simultaneous truth and performance level estimation (STAPLE). We evaluated model and rater performance through Dice similarity coefficient and in consensus. RESULTS: Consensus score of model performance showed acceptable results for all but one examination. Model performance and reader agreement had highest scores for level-1 signal (median Dice 0.68) and lowest scores for level-3 signal (median Dice 0.40), particularly in examinations where this signal was sparse. CONCLUSION: It is feasible to develop a deep-learning-based model for automated segmentation of bone marrow signal in children and adolescents. Our model performed poorest for the highest signal intensity in examinations where this signal was sparse. Further improvement requires training on larger and more balanced datasets and validation against ground truth, which should be established by radiologists from several institutions in consensus.
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Aprendizaje Profundo , Adolescente , Médula Ósea/diagnóstico por imagen , Niño , Estudios de Factibilidad , Humanos , Procesamiento de Imagen Asistido por Computador/métodos , Imagen por Resonancia Magnética/métodos , Espectroscopía de Resonancia Magnética , Estudios ProspectivosRESUMEN
Whole-body magnetic resonance imaging (MRI) is increasingly being used for a number of indications. Our aim was to review and describe indications and scan protocols for diagnostic value of whole-body MRI for multifocal disease in children and adolescents, we conducted a systematic search in Medline, Embase and Cochrane for all published papers until November 2018. Relevant subject headings and free text words were used for the following concepts: 1) whole-body, 2) magnetic resonance imaging and 3) child and/or adolescent. Included were papers in English with a relevant study design that reported on the use and/or findings from whole-body MRI examinations in children and adolescents. This review includes 54 of 1,609 papers identified from literature searches. Chronic nonbacterial osteomyelitis, lymphoma and metastasis were the most frequent indications for performing a whole-body MRI. The typical protocol included a coronal STIR (short tau inversion recovery) sequence with or without a coronal T1-weighted sequence. Numerous studies lacked sufficient data for calculating images resolution and only a few studies reported the acquired voxel volume, making it impossible for others to reproduce the protocol/images. Only a minority of the included papers assessed reliability tests and none of the studies documented whether the use of whole-body MRI affected mortality and/or morbidity. Our systematic review confirms significant variability of technique and the lack of proven validity of MRI findings. The information could potentially be used to boost attempts towards standardization of technique, reporting and guidelines development.
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Neoplasias , Osteomielitis , Adolescente , Niño , Humanos , Imagen por Resonancia Magnética , Reproducibilidad de los Resultados , Imagen de Cuerpo EnteroRESUMEN
BACKGROUND: Chronic nonbacterial osteomyelitis (CNO) is a rare autoinflammatory bone disorder. Little information exists on the use of imaging techniques in CNO. MATERIALS AND METHODS: We retrospectively reviewed clinical and MRI findings in children diagnosed with CNO between 2012 and 2018. Criteria for CNO included unifocal or multifocal inflammatory bone lesions, symptom duration >6 weeks and exclusion of infections and malignancy. All children had an MRI (1.5 tesla) performed at the time of diagnosis; 68 of these examinations were whole-body MRIs including coronal short tau inversion recovery sequences, with additional sequences in equivocal cases. RESULTS: We included 75 children (26 boys, or 34.7%), with mean age 10.5 years (range 0-17 years) at diagnosis. Median time from disease onset to diagnosis was 4 months (range 1.5-72.0 months). Fifty-nine of the 75 (78.7%) children presented with pain, with or without swelling or fever, and 17 (22.7%) presented with back pain alone. Inflammatory markers were raised in 46/75 (61.3%) children. Fifty-four of 75 (72%) had a bone biopsy. Whole-body MRI revealed a median number of 6 involved sites (range 1-27). Five children (6.7%) had unifocal disease. The most commonly affected bones were femur in 46 (61.3%) children, tibia in 48 (64.0%), pelvis in 29 (38.7%) and spine in 20 (26.7%). Except for involvement of the fibula and spine, no statistically significant differences were seen according to gender. CONCLUSION: Nearly one-fourth of the children presented with isolated back pain, particularly girls. The most common sites of disease were the femur, tibia and pelvic bones. Increased inflammatory markers seem to predict the number of MRI sites involved.
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Enfermedades Óseas , Osteomielitis , Adolescente , Niño , Preescolar , Femenino , Humanos , Lactante , Recién Nacido , Imagen por Resonancia Magnética , Masculino , Osteomielitis/diagnóstico por imagen , Estudios Retrospectivos , Columna VertebralRESUMEN
Juvenile idiopathic arthritis (JIA) is the most common paediatric rheumatic disease. It represents a group of heterogenous inflammatory disorders with unknown origin and is a diagnosis of exclusion in which imaging plays an important role. JIA is defined as arthritis of one or more joints that begins before the age of 16 years, persists for more than 6 weeks and is of unknown aetiology and pathophysiology. The clinical goal is early suppression of inflammation to prevent irreversible joint damage which has shifted the emphasis from detecting established joint damage to proactively detecting inflammatory change. This drives the need for imaging techniques that are more sensitive than conventional radiography in the evaluation of inflammatory processes as well as early osteochondral change. Physical examination has limited reliability, even if performed by an experienced clinician, emphasising the importance of imaging to aid in clinical decision-making. On behalf of the European Society of Musculoskeletal Radiology (ESSR) arthritis subcommittee and the European Society of Paediatric Radiology (ESPR) musculoskeletal imaging taskforce, based on literature review and/or expert opinion, we discuss paediatric-specific imaging characteristics of the most commonly involved, in literature best documented and clinically important joints in JIA, namely the temporomandibular joints (TMJs), spine, sacroiliac (SI) joints, wrists, hips and knees, followed by a clinically applicable point to consider for each joint. We will also touch upon controversies in the current literature that remain to be resolved with ongoing research. KEY POINTS: ⢠Juvenile idiopathic arthritis (JIA) is the most common chronic paediatric rheumatic disease and, in JIA imaging, is increasingly important to aid in clinical decision-making. ⢠Conventional radiographs have a lower sensitivity and specificity for detection of disease activity and early destructive change, as compared to MRI or ultrasound. Nonetheless, radiography remains important, particularly in narrowing the differential diagnosis and evaluating growth disturbances. ⢠Mainly in peripheral joints, ultrasound can be helpful for assessment of inflammation and guiding joint injections. In JIA, MRI is the most validated technique. MRI should be considered as the modality of choice to assess the axial skeleton or where the clinical presentation overlaps with JIA.
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Artritis Juvenil/diagnóstico , Imagen por Resonancia Magnética/métodos , Radiografía/métodos , Cintigrafía/métodos , Ultrasonografía/métodos , Niño , Humanos , Reproducibilidad de los ResultadosRESUMEN
Wrist involvement occurs in about one-quarter of patients diagnosed with juvenile idiopathic arthritis (JIA), increasing to 40% 5 years after diagnosis. The imaging appearances, both for active inflammation and permanent change, differ from those seen in adult rheumatoid arthritis; therefore, a child-specific approach is crucial for correct assessment. In this review article, we provide an update on the current status for imaging wrist JIA, with a focus on evidence-based practice.
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Artritis Juvenil/diagnóstico por imagen , Articulación de la Muñeca/diagnóstico por imagen , Artritis Juvenil/patología , Niño , Diagnóstico Diferencial , Humanos , Articulación de la Muñeca/patologíaRESUMEN
Imaging is increasingly being integrated into clinical practice to improve diagnosis, disease control and outcome in children with juvenile idiopathic arthritis. Over the last decades several international groups have been launched to standardize and validate different imaging techniques. To enhance transparency and facilitate collaboration, we present an overview of ongoing initiatives.
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Artritis Juvenil/diagnóstico , Diagnóstico por Imagen/tendencias , Niño , Conducta Cooperativa , Humanos , InternacionalidadRESUMEN
OBJECTIVE: The presence of findings at wrist MRI that may mimic disease is a diagnostic problem. The purpose of this study is to examine the occurrence of bone marrow changes resembling edema, joint fluid, and ganglion cysts over time, in a cohort of healthy children. MATERIALS AND METHODS: Seventy-four of 89 healthy children included in a study of normal MRI findings of the wrists were reexamined after a period of 4 years, using the same 1.5-T MRI technique-namely, a coronal T1-weighted and a T2-weighted fat-saturated sequence. A history of handedness, diseases, and sports activity was noted. RESULTS: Bone marrow edema or edemalike changes were seen in 29 of 74 (39.2%) wrists in 2013 as compared with 35 of 72 (48.6%) wrists in 2009 (p = 0.153), all in different locations. Changes were found in central parts of the bone, on both sides of a joint, or near bony depressions. Fifty percent of all subjects had at least one fluid pocket greater than or equal to 2 mm. The location was unchanged in 47% of the joints. In 24% of the individuals, at least one ganglion cyst was seen. Six ganglion cysts present on the first scan were not seen on the follow-up scan, and 11 new ganglion cysts had appeared. CONCLUSION: Awareness of normal MRI appearances of the growing skeleton is crucial when interpreting MRI of children, and such findings must not be interpreted as pathologic abnormalities.
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Enfermedades de la Médula Ósea/diagnóstico por imagen , Edema/diagnóstico por imagen , Ganglión/diagnóstico por imagen , Imagen por Resonancia Magnética , Quiste Sinovial/diagnóstico por imagen , Muñeca/diagnóstico por imagen , Adolescente , Enfermedades de la Médula Ósea/patología , Niño , Estudios de Cohortes , Diagnóstico Diferencial , Edema/patología , Reacciones Falso Positivas , Femenino , Estudios de Seguimiento , Ganglión/patología , Humanos , Masculino , Noruega , Valores de Referencia , Reproducibilidad de los Resultados , Sensibilidad y Especificidad , Quiste Sinovial/patología , Líquido Sinovial/citología , Muñeca/patologíaRESUMEN
BACKGROUND: Following coronary artery bypass grafting (CABG), testing for myocardial ischemia by noninvasive imaging is often hampered by false-positive results. The aim of this study was to find test parameters with the best potential to identify myocardial ischemia in post-CABG patients. METHODS: Fifty-two consecutive patients scheduled for CABG, underwent both dobutamine stress echocardiography (DSE) and cardiac magnetic resonance first-pass perfusion imaging (CMR-FPPI) with adenosine vasodilation, before and 8-10 months after the surgical revascularization. A pathologic biphasic stress response (PBR) expresses the presence of contractile reserve during low-dose dobutamine that decreases to hypo- or akinesia provoked by high-dose dobutamine. During DSE, potential PBR, segmental wall-motion score (WMS) as well as peak-systolic longitudinal strain (PLS) at peak-dose dobutamine were assessed. RESULTS: Post-CABG, there was still a relatively high prevalence of ischemia-positive segments evaluated by deformation imaging, but the number of such segments was significantly lower by PBR (20% and 22%) compared with peak-dose strain and WMS (62% and 77%, respectively; P<.05). The use of PBR instead of peak-dose WMS and strain could reduce the number of false-positive test results post-CABG. CONCLUSION: Among all imaging modalities tested, PBR by WMS and strain may be useful parameters for identifying patients with the need for new revascularization. We furthermore found that DSE may be interpreted as positive when revealing at least three ischemia-positive segments. The sensitivity of these test modalities for detecting coronary restenosis needs to be determined in further studies on a cohort of symptomatic post-CABG patients.
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Puente de Arteria Coronaria , Ecocardiografía de Estrés/métodos , Imagen por Resonancia Magnética/métodos , Isquemia Miocárdica/diagnóstico por imagen , Complicaciones Posoperatorias/diagnóstico por imagen , Cuidados Preoperatorios/métodos , Estudios de Cohortes , Medios de Contraste , Dobutamina , Femenino , Gadolinio DTPA , Corazón/diagnóstico por imagen , Corazón/fisiopatología , Humanos , Aumento de la Imagen/métodos , Masculino , Persona de Mediana Edad , Compuestos Organometálicos , Imagen de Perfusión , Estudios Prospectivos , Reproducibilidad de los ResultadosRESUMEN
BACKGROUND: A large proportion of healthy children have wrist changes on MRI, namely carpal depressions, findings that have been described as pathological in children with juvenile idiopathic arthritis. OBJECTIVE: We performed follow-up imaging in a cohort of healthy children to evaluate carpal surface depressions over time, focusing on the presence of overlying cartilage as a potential discriminator between normal variants and true erosions. MATERIALS AND METHODS: 74 of the initial cohort of 89 healthy children (83%) had a re-scan of their wrists using the same protocol, including coronal T1 and fat-saturated T2 sequences. A cartilage-selective sequence was added for this study. We registered number and location of bony depressions and presence of overlying cartilage. RESULTS: The total number of carpal depressions increased by age group and over time; their location was unchanged in 370 of 487 (76%) carpal sites and 91 of 117 (78%) metacarpal sites. In total, 426 of the 1,087 (39.2%) bony depressions were covered by cartilage, with a decreasing percentage by age (P = 0.001). CONCLUSION: Normal appearances during growth, such as bony depressions, should not be mistaken for pathology. There must be additional findings to support a diagnosis of disease. A cartilage sequence may add to the diagnostic image analysis.
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Envejecimiento/patología , Huesos del Carpo/diagnóstico por imagen , Huesos del Carpo/patología , Cartílago Articular/diagnóstico por imagen , Cartílago Articular/patología , Imagen por Resonancia Magnética/métodos , Adolescente , Niño , Estudios de Cohortes , Diagnóstico Diferencial , Femenino , Estudios de Seguimiento , Humanos , Estudios Longitudinales , Masculino , Valores de Referencia , Reproducibilidad de los Resultados , Sensibilidad y Especificidad , MuñecaRESUMEN
BACKGROUND: Potential long-term side effects of treatment for juvenile idiopathic arthritis are concerning. This has necessitated accurate tools, such as MRI, to monitor treatment response and allow for personalized therapy. OBJECTIVE: To examine the extent to which timing of post-contrast MR images influences the scoring of inflammatory change in the wrist in children with juvenile idiopathic arthritis. MATERIALS AND METHODS: We studied two sets of post-contrast 3-D gradient echo MRI series of the wrist in 34 children with juvenile idiopathic arthritis. These images were obtained immediately after administration of intravenous contrast material and again after approximately 10 min. The dataset was drawn from a prospective multicenter project conducted 2006-2010. We assessed five wrist locations for synovial enhancement, effusion and overall inflammation. Examinations were scored by one radiologist in two sessions - the first was based on the early post-contrast images, and the later session, for which the previous findings were masked, was based on the later post-contrast images. RESULTS: Fifty-two of the 170 locations (30.6%) received a higher synovial enhancement score based on the late post-contrast images as compared to the early images. Sixty of the 170 (35%) locations received a higher total inflammation score. The mean scores of synovial enhancement and total inflammation were significantly higher when based on the late post-contrast images as compared to the early post-contrast images. CONCLUSION: An MRI-based scoring system for the presence and degree of synovitis should be based on a standardized MR-protocol with a fixed interval between intravenous contrast injection and post-contrast images.
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Artritis Juvenil/diagnóstico por imagen , Artritis Juvenil/terapia , Imagen por Resonancia Magnética/métodos , Sinovitis/diagnóstico por imagen , Sinovitis/terapia , Articulación de la Muñeca/diagnóstico por imagen , Adolescente , Niño , Medios de Contraste , Femenino , Humanos , Imagenología Tridimensional , Masculino , Meglumina , Compuestos Organometálicos , Estudios ProspectivosRESUMEN
BACKGROUND: This study was designed to assess whether altered RV geometry and deformation parameters persisted well into the recovery period after presumably uncomplicated coronary artery bypass grafting (CABG). It was our hypothesis that the altered geometry of and load in the RV following pericardial opening would change both regional and global deformation indices for an extensive period postoperatively. METHODS AND RESULTS: Fifty-seven patients scheduled for CABG underwent preoperative and 8-10 months postoperative magnetic resonance imaging (MRI) for RV volume measurements, and resting echocardiography with assessment of geometry and RV mechanical function determined by tissue Doppler imaging (TDI) based longitudinal strain. Both MRI and echocardiography revealed postoperative dilatation of the RV apex, shortened longitudinal RV length but unchanged RV ejection fraction. Echocardiography parameters associated with filling of the right atrium showed signs of constraint with a reduced systolic filling fraction and increased right atrial size. Right ventricular segmental strain (-20 ± 13% vs. -29 ± 20% preoperatively; mean ±SD, P < 0.0001) was reduced postoperatively in parallel with TAPSE (1.3 ± 0.3 cm vs. 2.2 ± 0.4 cm; P < 0.0001). CONCLUSION: Post-CABG longitudinal motion of the RV lateral wall is reduced after uneventful CABG despite preserved RV ejection fraction and stroke volume. The discrepancy in various RV systolic performance indicators results from increased sphericity of the RV following opening the pericardium during surgery. Therefore, longitudinal functional parameters may underestimate RV systolic function for at least 8-10 months post-CABG. Changes in deformation parameters should thus always be interpreted in relation to changes in geometry.
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Puente de Arteria Coronaria/efectos adversos , Ecocardiografía/métodos , Ventrículos Cardíacos/patología , Ventrículos Cardíacos/fisiopatología , Imagen por Resonancia Magnética/métodos , Disfunción Ventricular Derecha/fisiopatología , Adulto , Anciano , Anciano de 80 o más Años , Módulo de Elasticidad , Diagnóstico por Imagen de Elasticidad/métodos , Femenino , Ventrículos Cardíacos/diagnóstico por imagen , Humanos , Interpretación de Imagen Asistida por Computador/métodos , Masculino , Persona de Mediana Edad , Imagen Multimodal/métodos , Variaciones Dependientes del Observador , Tamaño de los Órganos , Reproducibilidad de los Resultados , Sensibilidad y Especificidad , Estrés Mecánico , Disfunción Ventricular Derecha/diagnóstico , Disfunción Ventricular Derecha/etiologíaRESUMEN
BACKGROUND: Bony depressions at the wrist resembling erosions are frequently seen on MRI in healthy children. The accuracy of MRI in detecting early bony destruction is therefore questionable. We compared findings on MRI of the wrist in healthy children and those with juvenile idiopathic arthritis (JIA) to investigate markers for true disease. MATERIALS AND METHODS: We compared the number and localisation of bony depressions at the wrist in 85 healthy children and 68 children with JIA, ages 5-15 years. The size of the wrist was assessed from a radiograph of the wrist performed on the same day as the MRI. RESULTS: No significant difference in the number of bony depressions in the carpal bones was seen between healthy children and children with JIA at any age. Depressions are found in similar locations in the two groups, except for a few sites, where bony depressions were seen exclusively in the JIA group, particularly at the CMC joints. The wrist was significantly smaller in children with JIA (P < 0.001). CONCLUSIONS: Using adult scoring systems and standard MR sequences in the assessment of bone destruction in children may lead to overstaging or understaging of disease. At present, standard MRI sequences cannot easily be used for assessment of early signs of erosions in children.
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Artritis Juvenil/epidemiología , Artritis Juvenil/patología , Imagen por Resonancia Magnética/métodos , Imagen por Resonancia Magnética/estadística & datos numéricos , Articulación de la Muñeca/anomalías , Articulación de la Muñeca/patología , Adolescente , Estudios de Casos y Controles , Niño , Preescolar , Diagnóstico Diferencial , Femenino , Humanos , Masculino , Noruega/epidemiología , Prevalencia , Estudios Prospectivos , Valores de Referencia , Reproducibilidad de los Resultados , Sensibilidad y EspecificidadRESUMEN
OBJECTIVE: When performing whole-body MRI for bone marrow assessment in children, optimizing scan time is crucial. The aim was to compare T2 Dixon fat-only and TSE T1-weighted sequences in the assessment of bone marrow high signal areas seen on T2 Dixon water-only in healthy children and adolescents. MATERIALS AND METHODS: Whole-body MRIs from 196 healthy children and adolescents aged 6 to 19 years (mean 12.0) were obtained including T2 TSE Dixon and T1 TSE-weighted images. Areas with increased signal on T2 Dixon water-only images were scored using a novel, validated scoring system and classified into "minor" or "major" findings according to size and intensity, where "major" referred to changes easily being misdiagnosed as pathology in a clinical setting. Areas were assessed for low signal on T2 Dixon fat-only images and, after at least three weeks to avoid recall bias, on the T1-weighted sequence by two experienced pediatric radiologists. RESULTS: 1250 high signal areas were evaluated on T2 Dixon water-only images. In 1159/1250 (92.7%) low signal was seen on both T2 Dixon fat-only and T1-weighted sequences while in 24 (1.9%) it was not present on either sequence, with an absolute agreement of 94.6%. Discordant findings were found in 67 areas, of which in 18 (1.5%) low signal was visible on T1-weighted images alone and in 49 (3.9%) on T2 Dixon fat-only alone. The overall kappa value between the two sequences was 0.39. The agreement was higher for major as compared to minor findings (kappa values of 0.69 and 0.29, respectively) and higher for the older age groups. CONCLUSION: T2 Dixon fat-only can replace T1-weighted sequence on whole-body MRI for bone marrow assessment in children over the age of nine, thus reducing scan time.
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Médula Ósea , Imagen por Resonancia Magnética , Humanos , Adolescente , Niño , Anciano , Médula Ósea/diagnóstico por imagen , Imagen por Resonancia Magnética/métodos , Imagen de Cuerpo EnteroRESUMEN
BACKGROUND: The presence of erosions is used for diagnosis and monitoring of disease activity in juvenile idiopathic arthritis (JIA). Assessment of carpal bone erosions in children is challenging due to lack of normal references. OBJECTIVE: To define normal appearances of bony depressions in the wrist on radiographs and MRI. MATERIALS AND METHODS: MRI and radiography of the wrist were performed in 88 healthy children, 5-15 years of age. We assessed the number of bony depressions within the carpals/proximal metacarpals on both modalities, separately and combined. RESULTS: A total of 75 carpal depressions were identified on radiography compared to 715 on MRI. The number of bony depressions identified radiographically showed no statistically significant difference across age-groups. Within the metacarpals, there was no significant difference between bony depressions identified by MRI or radiography, except at the bases of the second metacarpal. CONCLUSION: Bony depressions that resemble erosions are normal findings in the wrist in children. MRI identifies more depressions than radiographs in the carpus. Some bony depressions occur at typical locations and should be accounted for when assessing the wrist in JIA to avoid overstaging.
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Artritis/diagnóstico por imagen , Artritis/etiología , Imagen por Resonancia Magnética/métodos , Osteólisis/complicaciones , Osteólisis/diagnóstico , Articulación de la Muñeca/diagnóstico por imagen , Articulación de la Muñeca/patología , Adolescente , Niño , Preescolar , Femenino , Humanos , Masculino , Radiografía , Reproducibilidad de los Resultados , Sensibilidad y Especificidad , Película para Rayos XRESUMEN
OBJECTIVE: To describe the findings of focal high signal on T2 weighted (T2W) images of the bone marrow in the axial skeleton as assessed by whole-body MRI in healthy and asymptomatic children and adolescents. MATERIAL AND METHODS: We assessed the bone marrow of the mandible, shoulder girdle, thorax, spine, and pelvis on water-only Dixon T2W sequences as part of a whole-body MRI protocol in 196 healthy and asymptomatic children aged 5-19 years. Intensity (0-2 scale) and extension (1-4 scale) of focal high signal areas in the bone marrow were scored and divided into minor or major findings, based on intensity and extension to identify the potentially conspicuous lesions in a clinical setting. RESULTS: We registered 415 areas of increased signal in the axial skeleton whereof 75 (38.3%) were major findings. Fifty-eight (29.6%) individuals had at least one major finding, mainly located in the pelvis (54, 72%). We found no differences according to gender. The number of minor findings increased with age (p = 0.020), but there were no significant differences in the number of major findings. The most conspicuous findings were in the pelvis, spine and sternum. CONCLUSION: Non-specific bone marrow T2W hyperintensities in the axial skeleton are frequently detected on whole-body MRI in healthy, asymptomatic children. Awareness of this is important as some findings may resemble clinically silent lesions in children with suspected multifocal skeletal disease.
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Imagen por Resonancia Magnética , Imagen de Cuerpo Entero , Adolescente , Médula Ósea/diagnóstico por imagen , Huesos , Niño , Humanos , Imagen por Resonancia Magnética/métodos , TóraxRESUMEN
OBJECTIVE: To describe the appearances of bone marrow in the appendicular skeleton on fat-suppressed T2-weighted sequences as assessed by whole-body MRI in healthy and asymptomatic children and adolescents. MATERIAL AND METHODS: Following ethical approval, we assessed the bone marrow of the extremities on water-only Dixon T2-weighted images as part of a whole-body MRI in 196 healthy and asymptomatic children aged 5-19 years. Based on a newly devised and validated scoring system, we graded intensity (0-2 scale) and extension (1-4 scale) of focal high signal bone marrow areas, and divided them into minor or major findings, based on intensity and extension, reflecting their potential conspicuousness in a clinical setting. RESULTS: In the upper extremity, we registered 366 areas with increased signal whereof 79 were major findings. In the lower extremities there were 675 areas of increased signal of which 340 were major findings. Hundred-and-fifteen (58.79%) individuals had at least one major finding, mainly located in the hand and proximal humerus, and the feet and knees. We found no differences according to gender, reported hours of sports activity, handedness, or age group, except for more minor findings in the upper extremities amongst 15-18-year-olds as compared to those aged 5-8 years. CONCLUSION: Focal areas of high signal intensity on whole-body MRI, T2-weighted fat suppressed images that, in a clinical setting could cause concern, were seen in more than half of healthy, asymptomatic children and adolescents. Awareness of this is important when interpreting whole-body MRI in this age group, particularly in the assessment of clinically silent lesions.
Asunto(s)
Imagen por Resonancia Magnética , Imagen de Cuerpo Entero , Adolescente , Médula Ósea/diagnóstico por imagen , Médula Ósea/patología , Niño , Pie , Humanos , Húmero , Imagen por Resonancia Magnética/métodosRESUMEN
In Alpha-mannosidosis (MIM 248500) the patients accumulate mainly unbranched oligosaccharide chains in the lysosomes in all body tissues, including the brain. With ensuing therapeutic modalities in man (BMT and ERT) non-invasive methods of monitoring the effect of treatment are needed. Paramount is the possible effect of the treatment on the brain, since this organ is regarded as difficult to reach because of the blood-brain barrier. We therefore performed proton nuclear magnetic resonance spectroscopy (MRS) of the brain in two untreated patients, and a 16-year-old patient treated with BMT at the age of 10 to assess whether this non-invasive method could be applied in the monitoring of the accumulation of abnormal chemicals in the brain of patients. We found an abnormal peak that was not present in the treated patient. A similar pattern was also found in MRS of urine from patients, reflecting the concentration of oligosaccharides in serum and tissues. We therefore conclude that MRS can be a useful method to monitor the effect of treatment for Alpha-Mannosidosis.