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1.
Radiographics ; 44(5): e230153, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38602868

RESUMEN

RASopathies are a heterogeneous group of genetic syndromes caused by germline mutations in a group of genes that encode components or regulators of the Ras/mitogen-activated protein kinase (MAPK) signaling pathway. RASopathies include neurofibromatosis type 1, Legius syndrome, Noonan syndrome, Costello syndrome, cardiofaciocutaneous syndrome, central conducting lymphatic anomaly, and capillary malformation-arteriovenous malformation syndrome. These disorders are grouped together as RASopathies based on our current understanding of the Ras/MAPK pathway. Abnormal activation of the Ras/MAPK pathway plays a major role in development of RASopathies. The individual disorders of RASopathies are rare, but collectively they are the most common genetic condition (one in 1000 newborns). Activation or dysregulation of the common Ras/MAPK pathway gives rise to overlapping clinical features of RASopathies, involving the cardiovascular, lymphatic, musculoskeletal, cutaneous, and central nervous systems. At the same time, there is much phenotypic variability in this group of disorders. Benign and malignant tumors are associated with certain disorders. Recently, many institutions have established multidisciplinary RASopathy clinics to address unique therapeutic challenges for patients with RASopathies. Medications developed for Ras/MAPK pathway-related cancer treatment may also control the clinical symptoms due to an abnormal Ras/MAPK pathway in RASopathies. Therefore, radiologists need to be aware of the concept of RASopathies to participate in multidisciplinary care. As with the clinical manifestations, imaging features of RASopathies are overlapping and at the same time diverse. As an introduction to the concept of RASopathies, the authors present major representative RASopathies, with emphasis on their imaging similarities and differences. ©RSNA, 2024 Test Your Knowledge questions for this article are available in the supplemental material.


Asunto(s)
Síndrome de Costello , Displasia Ectodérmica , Cardiopatías Congénitas , Síndrome de Noonan , Recién Nacido , Humanos , Síndrome de Noonan/diagnóstico por imagen , Síndrome de Noonan/genética , Cardiopatías Congénitas/diagnóstico por imagen , Cardiopatías Congénitas/genética , Displasia Ectodérmica/diagnóstico por imagen , Displasia Ectodérmica/genética , Radiólogos
2.
Pediatr Radiol ; 51(13): 2461-2469, 2021 12.
Artículo en Inglés | MEDLINE | ID: mdl-34351495

RESUMEN

Diagnostic imaging of the pediatric stomach often provides a challenge for practicing radiologists. Radiologists should be aware of relatively unusual congenital pathology, especially when imaging very young children with gastrointestinal symptoms. We review congenital pathology of the pediatric stomach.


Asunto(s)
Anomalías Congénitas , Enfermedades Gastrointestinales , Niño , Preescolar , Humanos , Estómago/diagnóstico por imagen
3.
AJR Am J Roentgenol ; 216(6): 1649-1658, 2021 06.
Artículo en Inglés | MEDLINE | ID: mdl-32845713

RESUMEN

BACKGROUND. Costochondral junction (CCJ) rib fractures pose a challenge in the radiographic detection and dating of infant abuse. OBJECTIVE. The purpose of this article was to assess the temporal pattern of radio-graphic findings of CCJ fractures on a serial skeletal survey (SS). METHODS. Reports of SSs performed for suspected infant abuse were reviewed to identify those reporting a CCJ fracture. Study inclusion required undergoing initial and approximately 2-week follow-up SSs that included anteroposterior and bilateral oblique radiographs of the reported CCJ rib fracture. Two pediatric radiologists retrospectively classified fractures in terms of the primary injury pattern (bucket-handle: visible crescentic fracture line; corner: visible triangular fracture line; other) and secondary healing pattern (growth disturbance; sclerosis; subperiosteal new bone formation [SPNBF]). Discrepant readings were resolved by consensus. RESULTS. The final cohort included 26 infants with 81 CCJ fractures. On initial SS, 59% (48/81) of fractures showed a primary pattern, most commonly a bucket-handle pattern (46%; 37/81); 6% (5/81) showed a primary pattern on follow-up SS (p < .001). On initial SS, the prevalence of a secondary pattern was 89% (72/81), most commonly a growth disturbance (85%; 69/81), followed by sclerosis (57%; 46/81); 80% (65/81) showed a secondary pattern on follow-up SS (p = .12). Overall prevalence of SPNBF was 28% (23/81). Addition of bilateral oblique views on initial SS resulted in a significant increase relative to the anteroposterior views alone in the detection of primary and secondary patterns by 15% (p = .04) and 30% (p < .001), respectively. CONCLUSION. A bucket-handle appearance is the most common primary pattern of fracture. The significantly lower prevalence of a primary pattern on follow-up vs initial SSs suggests that the CCJ fracture line is usually visible for only approximately 2 weeks. A growth disturbance of the rib end is the most common secondary pattern, followed by bony sclerosis, consistent with a healing injury. SPNBF is uncommon. Most CCJ fractures are in a healing phase at initial diagnosis. The signs of repair commonly remain visible on 2-week follow-up. The increased diagnostic yield of oblique views provides support to the inclusion of these projections in routine SS protocols. CLINICAL IMPACT. The findings will help radiologists improve the diagnosis and dating of CCJ rib fractures.


Asunto(s)
Maltrato a los Niños/diagnóstico , Radiografía/métodos , Fracturas de las Costillas/diagnóstico por imagen , Femenino , Humanos , Lactante , Masculino , Estudios Retrospectivos , Costillas/diagnóstico por imagen
4.
Pediatr Radiol ; 50(9): 1284-1292, 2020 08.
Artículo en Inglés | MEDLINE | ID: mdl-32495175

RESUMEN

Splenic masses present a diagnostic challenge to radiologists and clinicians alike, with a relative paucity of data correlating radiologic findings to pathological diagnosis in the pediatric population. To illustrate splenic mass imaging findings and approximate lesion prevalence, we retrospectively reviewed all splenectomies and splenic biopsies for splenic masses at a single academic pediatric hospital over a 10-year period in patients 18 years and younger. A total of 31 splenic masses were analyzed. Lesion prevalence, pathology and imaging features associated with sampled splenic masses are described. The lesions encountered include benign splenic cysts (9), vascular anomalies (7), hamartoma (3), leukemia/lymphoma (3), granulomata (3) and metastasis (2). We also identified single cases of angiosarcoma, splenic cord capillary hemangioma, congestive hemorrhage, and benign smooth muscle neoplasm.


Asunto(s)
Enfermedades del Bazo/diagnóstico por imagen , Adolescente , Biopsia , Niño , Preescolar , Diagnóstico Diferencial , Femenino , Humanos , Lactante , Masculino , Estudios Retrospectivos , Esplenectomía , Enfermedades del Bazo/patología , Enfermedades del Bazo/cirugía
5.
Pediatr Radiol ; 50(9): 1180-1190, 2020 08.
Artículo en Inglés | MEDLINE | ID: mdl-32474774

RESUMEN

Diagnostic imaging of pediatric gastric masses often provides a challenge for the practicing radiologist. Radiologists should be aware of this relatively unusual pathology, particularly in cross-sectional imaging findings. We will review pediatric gastric masses and mass-like lesions, focusing on neoplastic and inflammatory etiologies.


Asunto(s)
Anomalías del Sistema Digestivo/diagnóstico por imagen , Gastropatías/diagnóstico por imagen , Adolescente , Niño , Preescolar , Medios de Contraste , Diagnóstico Diferencial , Humanos , Lactante , Recién Nacido
6.
Top Magn Reson Imaging ; 28(5): 245-254, 2019 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-31592991

RESUMEN

Fetal magnetic resonance imaging (MRI) has been gaining increasing interest in both clinical radiology and research. Echoplanar imaging (EPI) offers a unique potential, as it can be used to acquire images very fast. It can be used to freeze motion, or to get multiple images with various contrast mechanisms that allow studying the microstructure and function of the fetal brain and body organs. In this article, we discuss the current clinical and research applications of fetal EPI. This includes T2*-weighted imaging to better identify blood products and vessels, using diffusion-weighted MRI to investigate connections of the developing brain and using functional MRI (fMRI) to identify the functional networks of the developing brain. EPI can also be used as an alternative structural sequence when banding or standing wave artifacts adversely affect the mainstream sequences used routinely in structural fetal MRI. We also discuss the challenges with EPI acquisitions, and potential solutions. As EPI acquisitions are inherently sensitive to susceptibility artifacts, geometric distortions limit the use of high-resolution EPI acquisitions. Also, interslice motion and transmit and receive field inhomogeneities may create significant artifacts in fetal EPI. We conclude by discussing promising research directions to overcome these challenges to improve the use of EPI in clinical and research applications.


Asunto(s)
Imagen Eco-Planar/métodos , Enfermedades Fetales/diagnóstico por imagen , Encéfalo/diagnóstico por imagen , Encéfalo/embriología , Imagen de Difusión por Resonancia Magnética/métodos , Humanos , Pulmón/diagnóstico por imagen , Pulmón/embriología
7.
Pediatr Radiol ; 49(4): 551-558, 2019 04.
Artículo en Inglés | MEDLINE | ID: mdl-30607436

RESUMEN

BACKGROUND: The classic metaphyseal lesion (CML) is a strong indicator of infant abuse, and the distal tibia is one of the most common sites for this injury. OBJECTIVE: To determine the prevalence of subperiosteal new bone formation accompanying the distal tibial CMLs identified on infant skeletal surveys. MATERIALS AND METHODS: Skeletal surveys performed for suspected infant abuse (2005-2017) were reviewed. Inclusion criteria were 1) anteroposterior (AP) and lateral radiographs of a distal tibial CML from the initial survey, 2) AP radiograph from the 2-week follow-up survey, 3) additional fractures, 4) child protection team consults and 5) mandated report filing for suspected abuse. We identified 22 distal tibial CMLs from 16 infants. Radiographs of these lesions were shown on the picture archiving and communication system to two blinded pediatric radiologists. Readers indicated the presence/absence of subperiosteal new bone formation on individual and combinations of images. RESULTS: Inter-reader agreements were fair (kappa=0.47). The prevalence of subperiosteal new bone formation on initial AP radiograph was 34%. Significant increases in the prevalence were found with the addition of follow-up AP radiograph (57%; P<0.001), initial lateral radiograph (57%; P=0.002) and follow-up AP plus initial lateral radiographs (71%; P<0.001). Statistically significant increases in prevalence were also noted when the third view was added to the other two views (increase of 14%; P=0.024). CONCLUSION: Even when skeletal surveys include initial AP, lateral and follow-up AP radiographs of the tibia, nearly one-third of distal tibial CMLs will fail to demonstrate subperiosteal new bone formation.


Asunto(s)
Maltrato a los Niños/diagnóstico , Osteogénesis/fisiología , Tibia/diagnóstico por imagen , Tibia/lesiones , Fracturas de la Tibia/diagnóstico por imagen , Preescolar , Femenino , Humanos , Lactante , Masculino , Prevalencia
8.
J Pediatr Surg ; 53(6): 1137-1141, 2018 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-29622396

RESUMEN

BACKGROUND/PURPOSE: Although advances have been made in the prenatal diagnosis of esophageal atresia (EA), most neonates are not identified until after birth. The distended hypopharynx (DHP) has been suggested as a novel prenatal sign for EA. We assess its diagnostic accuracy and predictive value on ultrasound (US) and magnetic resonance imaging (MRI), both alone and in combination with the esophageal pouch (EP) and secondary signs of EA (polyhydramnios and a small or absent fetal stomach). METHODS: We retrospectively reviewed fetal US and MRI reports and medical records of 88 pregnant women evaluated for possible EA from 2000 to 2016. Seventy-five had postnatal follow-up that confirmed or disproved the diagnosis of EA and were included in our analysis. RESULTS: Seventy-five women had 107 study visits (range 1-4). DHP and/or EP were seen on US and/or MRI in 36% of patients, and 78% of those patients had EA. DHP was 24% more sensitive for EA than EP, while EP was 30% more specific. After 28weeks of gestation, DHP had a predictive accuracy for EA of 0.929 (P=0.001). CONCLUSIONS: DHP is a sensitive additional prenatal sign of EA. More accurate diagnosis of EA allows for improved counseling regarding delivery, postnatal evaluation, and surgical correction. TYPE OF STUDY: Diagnostic. LEVEL OF EVIDENCE: Level II.


Asunto(s)
Atresia Esofágica/diagnóstico por imagen , Hipofaringe/diagnóstico por imagen , Imagen por Resonancia Magnética , Ultrasonografía Prenatal , Atresia Esofágica/patología , Femenino , Estudios de Seguimiento , Humanos , Hipofaringe/patología , Recién Nacido , Masculino , Embarazo , Estudios Retrospectivos , Sensibilidad y Especificidad
9.
J Pediatr Surg ; 53(3): 548-552, 2018 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-28351519

RESUMEN

INTRODUCTION: Blunt abdominal trauma is a common problem in children. Computed tomography (CT) is the gold standard for imaging in pediatric blunt abdominal trauma, however up to 50% of CTs are normal and CT carries a risk of radiation-induced cancer. Contrast enhanced ultrasound (CEUS) may allow accurate detection of abdominal organ injuries while eliminating exposure to ionizing radiation. METHODS: Children aged 7-18years with a CT-diagnosed abdominal solid organ injury underwent grayscale/power Doppler ultrasound (conventional US) and CEUS within 48h of injury. Two blinded radiologists underwent a brief training in CEUS and then interpreted the CEUS images without patient interaction. Conventional US and CEUS images were compared to CT for the presence of injury and, if present, the injury grade. Patients were monitored for contrast-related adverse reactions. RESULTS: Twenty one injured organs were identified by CT in eighteen children. Conventional US identified the injuries with a sensitivity of 45.2%, which increased to 85.7% using CEUS. The specificity of conventional US was 96.4% and increased to 98.6% using CEUS. The positive predictive value increased from 79.2% to 94.7% and the negative predictive value from 85.3% to 95.8%. Two patients had injuries that were missed by both radiologists on CEUS. In a 100kg, 17year old female, a grade III liver injury was not seen by either radiologist on CEUS. Her accompanying grade I kidney injury was not seen by one of the radiologist on CEUS. The second patient, a 16year old female, had a grade III splenic injury that was missed by both radiologists on CEUS. She also had an adjacent grade II kidney injury that was seen by both. Injuries, when noted, were graded within 1 grade of CT 33/35 times with CEUS. There were no adverse reactions to the contrast. CONCLUSION: CEUS is a promising imaging modality that can detect most abdominal solid organ injuries in children while eliminating exposure to ionizing radiation. A multicenter trial is warranted before widespread use can be recommended. LEVEL OF EVIDENCE: Level II; Diagnostic Prospective Study.


Asunto(s)
Traumatismos Abdominales/diagnóstico por imagen , Ultrasonografía/métodos , Heridas no Penetrantes/diagnóstico por imagen , Adolescente , Niño , Medios de Contraste , Femenino , Humanos , Riñón/lesiones , Hígado/lesiones , Masculino , Estudios Prospectivos , Sensibilidad y Especificidad , Bazo/lesiones , Tomografía Computarizada por Rayos X
10.
J Pediatr Surg ; 52(6): 933-937, 2017 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-28385427

RESUMEN

PURPOSE: Percent predicted lung volume (PPLV)<15% on fetal MRI predicts high-risk CDH. Potential changes in PPLV throughout gestation and impact on risk stratification are unknown. We reviewed CDH patients with serial fetal MRIs to follow PPLV and determine correlation with postnatal outcomes. METHODS: CDH patients with serial fetal MRIs from 2005 to 2015 were included. We recorded prenatal MRI gestational age (GA) and PPLV, postnatal ECMO use, and survival. Data were analyzed by logistic regression and Fisher's exact test. RESULTS: 57 patients had 127 fetal MRI studies. PPLV decreased from mean 25.4% to 19.6% between GA 22.1 and 32.6weeks. A steeper decline in PPLV, regardless of final PPLV, was independently predictive of higher ECMO use (p=0.046) and death (p=0.045). All patients with first PPLV<15% remained high-risk with poor outcomes. Of those with first PPLV>15%, 31% dropped below 15%, having similar ECMO use as the high-risk cohort, but trending toward greater survival (p=0.09). Those with first and final PPLV>15% had significantly less ECMO use (p=0.015) and greater survival (p<0.001) than the high-risk cohort. CONCLUSIONS: On average, PPLV decreases throughout gestation in fetuses with CDH. Serial MRI is recommended for those with initial PPLV>15%, as clinical outcomes tend to mirror the lowest PPLV. TYPE OF STUDY: Treatment study LEVEL OF EVIDENCE: III.


Asunto(s)
Hernias Diafragmáticas Congénitas/diagnóstico por imagen , Pulmón/diagnóstico por imagen , Imagen por Resonancia Magnética , Diagnóstico Prenatal , Oxigenación por Membrana Extracorpórea , Femenino , Estudios de Seguimiento , Edad Gestacional , Hernias Diafragmáticas Congénitas/embriología , Hernias Diafragmáticas Congénitas/mortalidad , Hernias Diafragmáticas Congénitas/terapia , Humanos , Recién Nacido , Modelos Logísticos , Pulmón/embriología , Pulmón/fisiopatología , Mediciones del Volumen Pulmonar , Masculino , Embarazo , Pronóstico , Estudios Retrospectivos
11.
J Magn Reson Imaging ; 44(6): 1650-1655, 2016 12.
Artículo en Inglés | MEDLINE | ID: mdl-27159847

RESUMEN

PURPOSE: To evaluate the feasibility of using diffusion-weighted magnetic resonance imaging (DW-MRI) to assess the fetal lung apparent diffusion coefficient (ADC) at 3 Tesla (T). MATERIALS AND METHODS: Seventy-one pregnant women (32 second trimester, 39 third trimester) were scanned with a twice-refocused Echo-planar diffusion-weighted imaging sequence with 6 different b-values in 3 orthogonal diffusion orientations at 3T. After each scan, a region-of-interest (ROI) mask was drawn to select a region in the fetal lung and an automated robust maximum likelihood estimation algorithm was used to compute the ADC parameter. The amount of motion in each scan was visually rated. RESULTS: When scans with unacceptable levels of motion were eliminated, the lung ADC values showed a strong association with gestational age (P < 0.01), increasing dramatically between 16 and 27 weeks and then achieving a plateau around 27 weeks. CONCLUSION: We show that to get reliable estimates of ADC values of fetal lungs, a multiple b-value acquisition, where motion is either corrected or considered, can be performed. J. Magn. Reson. Imaging 2016;44:1650-1655.


Asunto(s)
Envejecimiento/fisiología , Imagen de Difusión Tensora/métodos , Edad Gestacional , Pulmón/embriología , Pulmón/fisiología , Diagnóstico Prenatal/métodos , Difusión , Estudios de Factibilidad , Femenino , Humanos , Aumento de la Imagen/métodos , Interpretación de Imagen Asistida por Computador/métodos , Pulmón/diagnóstico por imagen , Masculino , Reproducibilidad de los Resultados , Sensibilidad y Especificidad , Estadística como Asunto
12.
Pediatr Radiol ; 46(3): 342-56, 2016 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-26637315

RESUMEN

BACKGROUND: Bone age in infants (<1 year old) is generally estimated using hand/wrist or knee radiographs, or by counting ossification centers. The accuracy and reproducibility of these techniques are largely unknown. OBJECTIVE: To develop and validate an infant bone age estimation technique using fibular shaft length and compare it to conventional methods. MATERIALS AND METHODS: We retrospectively reviewed negative skeletal surveys of 247 term-born low-risk-of-abuse infants (no persistent child protection team concerns) from July 2005 to February 2013, and randomized them into two datasets: (1) model development (n = 123) and (2) model testing (n = 124). Three pediatric radiologists measured all fibular shaft lengths. An ordinary linear regression model was fitted to dataset 1, and the model was evaluated using dataset 2. Readers also estimated infant bone ages in dataset 2 using (1) the hemiskeleton method of Sontag, (2) the hemiskeleton method of Elgenmark, (3) the hand/wrist atlas of Greulich and Pyle, and (4) the knee atlas of Pyle and Hoerr. For validation, we selected lower-extremity radiographs of 114 normal infants with no suspicion of abuse. Readers measured the fibulas and also estimated bone ages using the knee atlas. Bone age estimates from the proposed method were compared to the other methods. RESULTS: The proposed method outperformed all other methods in accuracy and reproducibility. Its accuracy was similar for the testing and validating datasets, with root-mean-square error of 36 days and 37 days; mean absolute error of 28 days and 31 days; and error variability of 22 days and 20 days, respectively. CONCLUSION: This study provides strong support for an infant bone age estimation technique based on fibular shaft length as a more accurate alternative to conventional methods.


Asunto(s)
Determinación de la Edad por el Esqueleto/métodos , Peroné/anatomía & histología , Peroné/diagnóstico por imagen , Modelos Biológicos , Modelos Estadísticos , Interpretación de Imagen Radiográfica Asistida por Computador/métodos , Simulación por Computador , Femenino , Peroné/fisiología , Humanos , Lactante , Recién Nacido , Masculino , Variaciones Dependientes del Observador , Reproducibilidad de los Resultados , Sensibilidad y Especificidad , Método Simple Ciego
13.
Artículo en Inglés | MEDLINE | ID: mdl-26225129

RESUMEN

Fetal magnetic resonance imaging (MRI) examinations have become well-established procedures at many institutions and can serve as useful adjuncts to ultrasound (US) exams when diagnostic doubts remain after US. Due to fetal motion, however, fetal MRI exams are challenging and require the MR scanner to be used in a somewhat different mode than that employed for more routine clinical studies. Herein we review the techniques most commonly used, and those that are available, for fetal MRI with an emphasis on the physics of the techniques and how to deploy them to improve success rates for fetal MRI exams. By far the most common technique employed is single-shot T2-weighted imaging due to its excellent tissue contrast and relative immunity to fetal motion. Despite the significant challenges involved, however, many of the other techniques commonly employed in conventional neuro- and body MRI such as T1 and T2*-weighted imaging, diffusion and perfusion weighted imaging, as well as spectroscopic methods remain of interest for fetal MR applications. An effort to understand the strengths and limitations of these basic methods within the context of fetal MRI is made in order to optimize their use and facilitate implementation of technical improvements for the further development of fetal MR imaging, both in acquisition and post-processing strategies.

14.
Pediatr Surg Int ; 29(4): 397-400, 2013 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-23371299

RESUMEN

Enteric duplication cysts (EDC) are typically solitary lesions that occur throughout the alimentary tract. Postnatal diagnosis is often prompted when complications occur from bleeding, obstruction, or infection. We present a case of multiple EDC diagnosed prenatally, managed with prenatal and neonatal follow-up and resection in infancy. Prenatal detection allowed for optimal management prior to the development of symptoms or complications.


Asunto(s)
Quistes/diagnóstico por imagen , Enfermedades Fetales/cirugía , Enfermedades Intestinales/diagnóstico por imagen , Adulto , Quistes/congénito , Femenino , Humanos , Recién Nacido , Enfermedades Intestinales/congénito , Masculino , Embarazo , Resultado del Embarazo , Ultrasonografía Prenatal
15.
Prenat Diagn ; 33(2): 134-40, 2013 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-23255174

RESUMEN

BACKGROUND: There are over 30 cases of prenatally diagnosed sacral extensions or human 'tails' in the literature, including isolated and syndromic etiologies. Most cases were reported to resolve by the second trimester and postnatal course was benign. Our objective was to describe the prenatal findings, associated anomalies, and clinical outcome of a series of seven fetuses diagnosed prenatally with fetal sacrococcygeal extension. METHODS: In a prospective study on a series of 4040 consecutive patients seen through our clinic in a 10-year period, 7 patients had a sacrococcygeal extension identified on fetal imaging. Fetal sonographic and magnetic resonance imaging findings, results of genetic testing, and clinical outcomes were analyzed. RESULTS: All seven fetuses had associated anomalies, including neurologic, craniofacial, cardiac, spinal, renal, and musculoskeletal abnormalities, or abnormal ultrasound findings including growth restriction and abnormal umbilical cord Doppler. There were two cases of trisomy 13 and one case of Pfeiffer syndrome. The mean gestational age at diagnosis was 19.3 weeks. CONCLUSION: When a sacrococcygeal extension is seen on fetal imaging, work-up should include detailed fetal imaging and karyotype, and fetal growth should be monitored. Our experience with fetal sacrococcygeal extension demonstrates variability in the underlying presentation and etiology, making counseling in a prenatal setting challenging.


Asunto(s)
Anomalías Congénitas/epidemiología , Región Sacrococcígea/anomalías , Adulto , Boston/epidemiología , Anomalías Congénitas/diagnóstico por imagen , Femenino , Humanos , Embarazo , Segundo Trimestre del Embarazo , Estudios Prospectivos , Región Sacrococcígea/diagnóstico por imagen , Ultrasonografía Prenatal
16.
Open Orthop J ; 6: 231-8, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-22802918

RESUMEN

Collagen is an important biomaterial in intra-articular tissue engineering, but there are unanswered questions about its safety. We hypothesize that the addition of type-I-collagen for primary repair of the Anterior Cruciate Ligament (ACL) might result in a local and systemic reaction in a porcine model after 15 weeks as demonstrated by joint effusion, synovial thickening, elevated intraarticular and systemic leukocyte counts. Further, this reaction might be aggravated by the addition of a platelet concentrate. Eighteen porcine ACLs were transected and repaired with either sutures (n=6), a collagen sponge (n=6), or a collagen-platelet-composite (CPC; n=6). Twelve intact contralateral knees served as controls (n=12). No significant synovial thickening or joint effusion was seen in the collagen-treated knees. Synovial fluid leukocyte counts showed no significant differences between surgically treated and intact knees, and no differences were seen in leukocyte counts of the peripheral blood. The addition of a platelet concentrate to the knee joint resulted in lower serum levels of IL-1ß, but serum levels of TNF-α were not significantly different between groups. In conclusion, the presence of collagen, with or without added platelets, did not increase the local or systemic inflammatory reactions following surgery, suggesting that Type I collagen is safe to use in the knee joint.

17.
Radiology ; 262(1): 234-41, 2012 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-22106354

RESUMEN

PURPOSE: To examine radiographic findings in children with vitamin D deficiency in comparison with biochemical marker levels and prevalence of fractures. MATERIALS AND METHODS: The parents or guardians of all participants provided written informed consent at the time of enrollment. The institutional review board approved the protocol, and HIPAA guidelines were followed. From a prospective sample of children seen for routine clinical care, 40 children with vitamin D deficiency (25-hydroxyvitamin D [25-OHD] level, ≤ 20 ng/mL) were identified, and high-detail computed radiographs of the wrists and knees were obtained. The children ranged in age from 8 to 24 months. Radiographs were scored by three readers with use of the 10-point Thacher score for rachitic changes and a five-point scale for demineralization. Serum calcium, phosphorus, alkaline phosphatase, and parathyroid hormone levels were determined. Fracture history was obtained for 35 of the 40 patients (88%). RESULTS: All readers identified rachitic changes at both readings in two patients (5%) and demineralization in two patients (5%). Interrater agreement was 65% for rachitic changes (κ = 0.33) and 70% for demineralization (κ = 0.37). When the majority of the raters determined that rachitic changes were absent at both readings, alkaline phosphatase levels were lower than those with other assessments (median, 267 vs 515 U/L [4.4589 vs 8.6005 µkat/L]; P = .01). When most raters determined that demineralization was present at both readings, serum 25-OHD levels were lower than those at other assessments (median, 9.0 vs 17.5 ng/mL [22.464 vs 43.68 nmol/L]; P = .02). No fractures were reported or identified radiographically. CONCLUSION: In infants and toddlers with vitamin D deficiency, rachitic changes and definite demineralization are uncommon and fracture risk is low.


Asunto(s)
Fracturas Óseas/diagnóstico por imagen , Fracturas Óseas/etiología , Raquitismo/diagnóstico por imagen , Raquitismo/etiología , Deficiencia de Vitamina D/complicaciones , Deficiencia de Vitamina D/diagnóstico por imagen , Biomarcadores/sangre , Densidad Ósea , Niño , Preescolar , Femenino , Fracturas Óseas/epidemiología , Humanos , Lactante , Articulación de la Rodilla/diagnóstico por imagen , Masculino , Prevalencia , Radiografía , Raquitismo/epidemiología , Estadísticas no Paramétricas , Encuestas y Cuestionarios , Deficiencia de Vitamina D/sangre , Deficiencia de Vitamina D/epidemiología , Articulación de la Muñeca/diagnóstico por imagen
18.
J Biomech ; 44(16): 2843-6, 2011 Nov 10.
Artículo en Inglés | MEDLINE | ID: mdl-21962290

RESUMEN

Magnetic resonance imaging (MRI) could potentially be used to non-invasively predict the strength of an ACL graft after ACL reconstruction. We hypothesized that the volume and T2 relaxation parameters of the ACL graft measured with MRI will predict the graft structural properties and anteroposterior (AP) laxity of the reconstructed knee. Nine goats underwent ACL reconstruction using a patellar tendon autograft augmented with a collagen or collagen-platelet composite. After 6 weeks of healing, the animals were euthanized, and the reconstructed knees were retrieved and imaged on a 3T scanner. AP laxity was measured prior to dissecting out the femur-graft-tibia constructs which were then tested to tensile failure to determine the structural properties. Regression analysis indicated a statistically significant relationship between the graft volume and the failure load (r(2)=0.502; p=0.049). When graft volume was normalized to the T2 relaxation time, the relationship was even greater (r(2)=0.687; p=0.011). There was a significant correlation between the graft volume and the linear stiffness (r(2)=0.847; p<0.001), which remained significant with T2 normalization (r(2)=0.764; p=0.002). For AP laxity at 30° flexion, there was not a significant correlation with graft volume, but there was a significant correlation with volume normalized by the T2 relaxation time (r(2)=0.512; p=0.046). These results suggest that MRI volumetric measures combined with graft T2 properties may be useful in predicting the structural properties of ACL grafts.


Asunto(s)
Análisis de Falla de Equipo/métodos , Articulación de la Rodilla/diagnóstico por imagen , Prótesis de la Rodilla , Imagen por Resonancia Magnética , Modelos Biológicos , Soporte de Peso , Animales , Fémur/diagnóstico por imagen , Fémur/cirugía , Cabras , Articulación de la Rodilla/cirugía , Masculino , Radiografía , Tibia/diagnóstico por imagen , Tibia/cirugía
19.
AJR Am J Roentgenol ; 197(3): 713-9, 2011 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-21862816

RESUMEN

OBJECTIVE: Although not commonly used in current clinical practice, the PET agent (18)F-NaF provides an excellent alternative to the standard tracers used for radionuclide bone scintigraphy. This article illustrates the use and appearance of (18)F-NaF PET and shows examples of its utility in the assessment of bone pain in children. CONCLUSION: Skeletal imaging with (18)F-NaF harnesses both the superior imaging characteristics of PET and the improved biodistribution of the fluoride tracer in comparison with standard nuclear techniques, resulting in excellent-quality images that can effectively be used to investigate the cause of bone pain in children.


Asunto(s)
Dolor de Espalda/diagnóstico por imagen , Huesos/diagnóstico por imagen , Radioisótopos de Flúor , Tomografía de Emisión de Positrones/métodos , Adolescente , Niño , Diagnóstico Diferencial , Femenino , Humanos , Masculino , Fluoruro de Sodio , Adulto Joven
20.
Int J Comput Assist Radiol Surg ; 6(3): 329-39, 2011 May.
Artículo en Inglés | MEDLINE | ID: mdl-20625848

RESUMEN

PURPOSE: Fetal MRI volumetry is a useful technique but it is limited by a dependency upon motion-free scans, tedious manual segmentation, and spatial inaccuracy due to thick-slice scans. An image processing pipeline that addresses these limitations was developed and tested. MATERIALS AND METHODS: The principal sequences acquired in fetal MRI clinical practice are multiple orthogonal single-shot fast spin echo scans. State-of-the-art image processing techniques were used for inter-slice motion correction and super-resolution reconstruction of high-resolution volumetric images from these scans. The reconstructed volume images were processed with intensity non-uniformity correction and the fetal brain extracted by using supervised automated segmentation. RESULTS: Reconstruction, segmentation and volumetry of the fetal brains for a cohort of twenty-five clinically acquired fetal MRI scans was done. Performance metrics for volume reconstruction, segmentation and volumetry were determined by comparing to manual tracings in five randomly chosen cases. Finally, analysis of the fetal brain and parenchymal volumes was performed based on the gestational age of the fetuses. CONCLUSION: The image processing pipeline developed in this study enables volume rendering and accurate fetal brain volumetry by addressing the limitations of current volumetry techniques, which include dependency on motion-free scans, manual segmentation, and inaccurate thick-slice interpolation.


Asunto(s)
Encéfalo/embriología , Procesamiento de Imagen Asistido por Computador/métodos , Imagen por Resonancia Magnética/métodos , Femenino , Edad Gestacional , Humanos , Embarazo
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