RESUMEN
BACKGROUND: Accurate diagnosis of portal vein (PV) stenosis by real-time and color Doppler US (CD-US) after segmental liver transplantation in children can decrease morbidity by avoiding unnecessary biopsy, PV hypertension, thrombosis and loss of the graft. OBJECTIVE: To evaluate CD-US parameters for the prediction of PV stenosis after segmental liver transplantation in children. MATERIALS AND METHODS: We retrospectively reviewed 61 CD-US examinations measuring the diameter at the PV anastomosis, velocities at the anastomosis (PV1) and in the segment proximal to the anastomosis (PV2), and the PV1/PV2 velocity ratio. The study group comprised patients with stenosis confirmed by angiography and the control group comprised patients with a good clinical outcome. RESULTS: PV stenosis was seen in 12 CD-US examinations. The mean PV diameter was smaller in the study group (2.6 mm versus 5.7 mm) and a PV diameter of <3.5 mm was highly predictive of stenosis (sensitivity 100%, specificity 91.8%). CONCLUSION: A PV diameter of <3.5 mm is a highly predictive CD-US parameter for the detection of hemodynamically significant stenosis on angiography.
Asunto(s)
Enfermedad Veno-Oclusiva Hepática/diagnóstico por imagen , Trasplante de Hígado , Vena Porta/diagnóstico por imagen , Complicaciones Posoperatorias/diagnóstico por imagen , Ultrasonografía Doppler en Color , Adolescente , Anastomosis Quirúrgica , Angiografía , Niño , Preescolar , Femenino , Humanos , Lactante , Masculino , Valor Predictivo de las Pruebas , Curva ROC , Estudios Retrospectivos , Sensibilidad y EspecificidadRESUMEN
BACKGROUND: Accurate diagnosis of hepatic vein (HV) stenosis by real-time and color Doppler US (CD-US) after segmental liver transplantation in children can decrease morbidity because it allows unnecessary biopsy, obstruction or thrombosis and loss of the graft to be avoided. OBJECTIVE: To evaluate CD-US parameters to predict HV stenosis after segmental liver transplantation in children. MATERIALS AND METHODS: Retrospective review of 79 CD-US examinations measuring velocity at the HV anastomosis (HV1) and the main trunk 1-2 cm proximal to the HV/IVC anastomosis (HV2), the HV1/HV2 ratio and the spectral waveform of HV2. The study group comprised patients with stenosis confirmed by angiography. The control group comprised patients with a good clinical outcome. RESULTS: HV stenosis was seen in 12 CD-US examinations. The mean HV1/HV2 ratio was higher in the study group (6.0 versus 4.0). An HV1/HV2 ratio of >4.1 was predictive of HV stenosis (sensitivity 83%, specificity 76%). CONCLUSION: An HV1/HV2 ratio of >4.1 is a highly predictive CD-US parameter for the detection of hemodynamically significant HV stenosis on angiography.
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Venas Hepáticas/diagnóstico por imagen , Enfermedad Veno-Oclusiva Hepática/diagnóstico por imagen , Trasplante de Hígado , Complicaciones Posoperatorias/diagnóstico por imagen , Ultrasonografía Doppler en Color , Adolescente , Angiografía , Niño , Preescolar , Femenino , Humanos , Lactante , Masculino , Valor Predictivo de las Pruebas , Curva ROC , Estudios Retrospectivos , Sensibilidad y EspecificidadRESUMEN
OBJECTIVE: The purpose of this study was to determine whether prenatal MRI provides additional information about fetal sacrococcygeal teratoma compared with prenatal sonography. MATERIALS AND METHODS: Twenty-two pregnant women with fetal sacrococcygeal teratoma underwent prenatal MRI (mean gestational age, 23 weeks). The size, location, mass characteristics, and compressive effects of the tumors were determined and correlated with sonography and postnatal findings. RESULTS: Based on the MRI findings, the following American Academy of Pediatrics, Surgical Section classifications were assigned: type I in six patients, type II in 12, and type III in four. No type IV tumors were found. The sacrococcygeal teratoma appeared entirely cystic in five fetuses, microcystic in one, mixed cystic and solid in 12, and solid in four. The diagnosis of sacrococcygeal teratoma was accurate in all cases assessed at our center using both MRI and sonography. Two additional patients initially referred with the diagnosis of sacrococcygeal teratoma had a different diagnosis at reevaluation at our institution (healthy, n = 1; myelomeningocele, n = 1). MRI was superior to sonography for detecting displacement of the colon (n = 11), urinary tract dilatation (n = 9), hip dislocation (n = 4), intraspinal extension (n = 2), and vaginal dilation (n = 1). In fetuses with sacrococcygeal teratoma types II and III, MRI better showed the cephalic extent of the tumor compared with sonography. MRI findings were confirmed at surgery or autopsy in all patients. Three fetuses with high output cardiac physiology underwent open fetal resection of the tumor at 21-, 24-, and 26-weeks' gestational age with two surviving. CONCLUSION: Our results show that ultrafast fetal MRI is a useful adjunct to the prenatal evaluation of fetal sacrococcygeal teratoma. Compared with sonography, MRI more accurately characterized the intrapelvic and abdominal extent of the tumors and provided more information on compression of adjacent organs. The additional anatomic resolution provided by MRI resulted in more accurate prenatal counseling and improved preoperative planning for surgical resection.
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Enfermedades Fetales/diagnóstico , Imagen por Resonancia Magnética , Diagnóstico Prenatal , Región Sacrococcígea , Teratoma/congénito , Teratoma/diagnóstico , Femenino , Humanos , EmbarazoRESUMEN
The ability to identify and confidently diagnose a wide range of congenital fetal thoracic lesions has increased tremendously in the past 2 decades with the emergence of high-resolution sonography and ultrafast MRI sequences. Imaging studies constitute a vital component in the diagnosis of these lesions, whether in the fetal, neonatal or childhood periods. In addition to providing a road map for potential intervention, imaging techniques have provided important information about normal development, natural history, and prognosis. In the prenatal stage, these features aid in family counseling, pregnancy management, and the identification of a subgroup of patients who may benefit from fetal intervention. In the neonatal and childhood periods, imaging studies facilitate timely diagnosis and institution of appropriate therapeutic strategies.
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Diagnóstico Prenatal , Tórax/anomalías , Secuestro Broncopulmonar/diagnóstico , Preescolar , Anomalías Congénitas/diagnóstico , Malformación Adenomatoide Quística Congénita del Pulmón/diagnóstico , Quistes/congénito , Femenino , Enfermedades Fetales/diagnóstico , Hernias Diafragmáticas Congénitas , Humanos , Recién Nacido , Embarazo , Ultrasonografía PrenatalRESUMEN
Improvements in magnetic resonance imaging (MRI) technology continue to provide faster scan times and higher resolution increasing the applications for fetal imaging. MRI is an adjunct to good prenatal ultrasound scan (US). It provides significant additional information that improves diagnostic accuracy in evaluation of the fetal brain, spine, neck, chest, abdomen, and urinary tract. MRI provides important anatomic information that helps in planning delivery and surgical procedures.
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Enfermedades Fetales/diagnóstico , Imagen por Resonancia Magnética , Diagnóstico Prenatal , Abdomen/embriología , Neoplasias Abdominales/diagnóstico , Sistema Nervioso Central/anomalías , Sistema Nervioso Central/embriología , Femenino , Humanos , Riñón/anomalías , Riñón/embriología , Imagen por Resonancia Magnética/métodos , Embarazo , Enfermedades Torácicas/diagnóstico , Tórax/anomalías , Tórax/embriologíaRESUMEN
Presently, MRI is an adjunct to prenatal sonography. It provides information that can aid in the diagnosis of fetal anomalies, affect prenatal counseling and management of the pregnancy, and guide prenatal intervention and delivery planning. With further advances in technology, particularly shorter scan times and better image resolution, the applications for fetal imaging are likely to increase.
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Anomalías Congénitas/diagnóstico , Enfermedades Fetales/diagnóstico , Imagen por Resonancia Magnética/métodos , Diagnóstico Prenatal/métodos , HumanosRESUMEN
PURPOSE: To overcome the difficulty of poor signal-to-noise ratio of magnetic resonance imaging (MRI) in evaluating heavy iron overload by using a single voxel magnetic resonance spectroscopy (MRS) technique. MATERIALS AND METHODS: A single voxel STEAM pulse sequence with a minimum TE of 1.5 msec and a sampling volume of 36.6 cm(3) was developed and applied to 1/T2 measurement of the liver in 14 patients with thalassemia whose liver iron concentration was determined through biopsy. RESULTS: The iron level ranged from 0.23 to 37.15 mg Fe/g dry tissue with a median value of 18.06. In all cases, strong MR signals were obtained. 1/T2 was strongly correlated with the liver iron concentration (r = 0.95, P < 0.00005). CONCLUSION: The single voxel MRS measurement of T2 in liver iron overload overcomes the difficulty of lack of detectable signals in conventional MRI when the iron level is high. There is an excellent correlation between the iron level and 1/T2.
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Hierro/análisis , Hígado/química , Espectroscopía de Resonancia Magnética/métodos , Talasemia/metabolismo , Adolescente , Adulto , Niño , Femenino , Humanos , MasculinoRESUMEN
OBJECTIVE: Previous reports have suggested that 80% to 85% of patients who have a myelomeningocele (MMC) and undergo surgical repair after birth develop hydrocephalus and require the placement of a ventricular shunt. However, the rate of shunting as a function of spinal level is not well established. We sought to determine the distribution of postnatally repaired MMC lesions as characterized by both functional and radiologic assessment, as well as the incidence of shunting when patients were categorized according to these 2 methods. METHODS: A retrospective chart review of 297 patients who were born with open MMCs and followed in the spina bifida clinic at the Children's Hospital of Philadelphia was performed. The presence or absence of a shunt was determined for each patient. Functional spinal level was determined by the best-recorded neurologic examination and vertebral level by spine radiographs. RESULTS: The overall rate of ventricular shunting was 81%. The level of the lesion significantly affected the incidence of shunting, with more cephalad lesions correlating with higher rates. This was true both for functional and radiologic categorizations. A significantly higher shunt rate was found among patients with sacral lesions when categorized by radiologic rather than functional criteria. In 86% of patients, the functional level was found to be equal to or higher (worse) than the radiologic level. CONCLUSIONS: This study describes the natural history of ventricular shunting in MMC patients with relation to both radiologic and functional criteria. Fetal MMC closure is being performed in some centers in an attempt to decrease the incidence of shunting and to improve leg function in selected patients. The present data may serve as a comparison group and aid in the design and analysis of a prospective trial to assess the efficacy of this new procedure.