RESUMEN
BowelScreen paused activity in March 2020 to prioritise the response to the COVID-19 pandemic. The aim of this study was to examine the impact of this delay. Cases affected by the pause and subsequently completed were compared to the same period in 2019. Endoscopy and histology data were obtained from the BowelScreen database and patient records. One-hundred and seven colonoscopies were performed during the study period. This compared with 224 colonoscopies during the same period in 2019. Median lead time to colonoscopy in 2020 was 74 days compared to 34 days in 2019. Adenoma detection rate was 59% for both periods. Advanced adenoma and cancer detection rates were similar in both periods. While there was a marked reduction in activity and significant delays for BowelScreen patients during the first wave of the COVID-19 pandemic, this does not appear to have impacted on clinical outcomes for patients who attended for screening colonoscopy.
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Adenoma , COVID-19 , Neoplasias Colorrectales , Humanos , SARS-CoV-2 , Pandemias/prevención & control , Detección Precoz del Cáncer , Neoplasias Colorrectales/diagnóstico , Neoplasias Colorrectales/epidemiología , Colonoscopía , Tamizaje Masivo , Adenoma/diagnóstico , Adenoma/epidemiologíaRESUMEN
This review describes the features of modern infrared imaging technology and the standardization protocols for thermal imaging in medicine. The technique essentially uses naturally emitted infrared radiation from the skin surface. Recent studies have investigated the influence of equipment and the methods of image recording. The credibility and acceptance of thermal imaging in medicine is subject to critical use of the technology and proper understanding of thermal physiology. Finally, we review established and evolving medical applications for thermal imaging, including inflammatory diseases, complex regional pain syndrome and Raynaud's phenomenon. Recent interest in the potential applications for fever screening is described, and some other areas of medicine where some research papers have included thermal imaging as an assessment modality. In certain applications thermal imaging is shown to provide objective measurement of temperature changes that are clinically significant.
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Medicina/instrumentación , Termografía/métodos , Artritis/diagnóstico , Síndromes de Dolor Regional Complejo/diagnóstico , Diagnóstico por Imagen/instrumentación , Diagnóstico por Imagen/métodos , Diagnóstico por Imagen/normas , Fiebre/diagnóstico , Humanos , Inflamación/diagnóstico , Rayos Infrarrojos , Enfermedad de Raynaud/diagnóstico , Temperatura Cutánea , Termografía/instrumentación , Termografía/normasRESUMEN
Silicon microchips with thin, electron transparent silicon nitride windows provide a sample support that accommodates both light-, and electron microscopy of whole eukaryotic cells in vacuum or liquid, with minimum sample preparation steps. The windows are robust enough that cellular samples can be cultured directly onto them, with no addition of a supporting film, and there is no need to embed or section the sample, as is typically required in electron microscopy. By combining two microchips, a microfluidic chamber can be constructed for the imaging of samples in liquid in the electron microscope. We provide microchip design specifications, a fabrication outline, instructions on how to prepare the microchips for biological samples, and examples of images obtained using different light and electron microscopy modalities. The use of these microchips is particularly advantageous for correlative light and electron microscopy.
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Investigación Biomédica/métodos , Microscopía Electrónica/métodos , Compuestos de Silicona/química , Animales , Células COS , Chlorocebus aethiops , Microfluídica/métodosRESUMEN
Short-term increases in soil solution nitrate (NO(3)(-)) concentration are often observed after forest harvest, even in N-limited systems. We model NO(3)(-) leaching below the rooting zone as a function of site productivity. Using national forest inventories and published estimates of N attenuation in rivers and the riparian zone, we estimate effects of stem-only harvesting on NO(3)(-) leaching to groundwater, surface waters and the marine environment. Stem-only harvesting is a minor contributor to NO(3)(-) pollution of Swedish waters. Effects in surface waters are rapidly diluted downstream, but can be locally important for shallow well-waters as well as for the total amount of N reaching the sea. Harvesting adds approximately 8 Gg NO(3)-N to soil waters in Sweden, with local concentrations up to 7 mg NO(3)-N l(-1). Of that, â¼3.3 Gg reaches the marine environment. This is â¼3% of the overall Swedish N load to the Baltic.
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Agricultura Forestal/métodos , Nitratos/análisis , Tallos de la Planta/metabolismo , Árboles/fisiología , Monitoreo del Ambiente , Contaminantes del Suelo/análisis , Suecia , Contaminantes Químicos del Agua/análisisRESUMEN
Significant changes in recording of human body temperature have been taking place worldwide in recent years. The clinical thermometer introduced in the mid-19th century by Wunderlich has been replaced by digital thermometers or radiometer devices for recording tympanic membrane temperature. More recently the use of infrared thermal imaging for fever screening has become more widespread following the SARS infection, and particularly during the pandemic H1N1 outbreak. Important new standards that have now reached international acceptance will affect clinical and fever screening applications. This paper draws attention to these new standard documents. They are designed to improve the standardization of both performance and practical use of these key techniques in clinical medicine, especially necessary in a pandemic influenza situation.
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Temperatura Corporal , Termómetros , Humanos , TermografíaRESUMEN
Human body temperature has been an important part of medicine since very early times. However, until the thermometer was developed in the 16th century measurement was not possible. Some 200 years later, Wunderlich laid the foundation for clinical thermometry, and temperature charts became commonplace throughout the world. More recently thermal imaging has broadened the understanding of body surface temperature in health and disease. Standards for computer-assisted infrared imaging are well developed, and present-day fast high-resolution imaging is less expensive and more reliable than it was 40 years ago.
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Espectrofotometría Infrarroja/historia , Termografía/historia , Termómetros/historia , Historia del Siglo XVII , Historia del Siglo XVIII , Historia del Siglo XIX , Historia del Siglo XX , Historia del Siglo XXIRESUMEN
Our purpose here is to describe our experience with important hemobilia following PTBD and to determine whether left-sided percutaneous transhepatic biliary drainage (PTBD) is associated with an increased incidence of important hemobilia compared to right-sided drainages. We reviewed 346 transhepatic biliary drainages over a four-year period and identified eight patients (2.3%) with important hemobilia requiring transcatheter embolization. The charts and radiographic files of these patients were reviewed. The side of the PTBD (left versus right), and the order of the biliary ductal branch entered (first, second, or third) were recorded. Of the 346 PTBDs, 269 were right-sided and 77 were left-sided. Of the eight cases of important hemobilia requiring transcatheter embolization, four followed right-sided and four followed left-sided PTBD, corresponding to a bleeding incidence of 1.5% (4/269) for right PTBD and 5.2% (4/77) for left PTBD. The higher incidence of hemobilia associated with left-sided PTBD approached, but did not reach the threshold of statistical significance (p = 0.077). In six of the eight patients requiring transcatheter embolization, first or second order biliary branches were accessed by catheter for PTBD. All patients with left-sided bleeding had first or proximal second order branches accessed by biliary drainage catheters. In conclusion, a higher incidence of hemobilia followed left-versus right-sided PTBD in this study, but the increased incidence did not reach statistical significance.
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Conductos Biliares Intrahepáticos/cirugía , Drenaje/efectos adversos , Drenaje/métodos , Hemobilia/epidemiología , Adulto , Anciano , Conductos Biliares Intrahepáticos/diagnóstico por imagen , Conductos Biliares Intrahepáticos/patología , Colangiografía , Embolización Terapéutica/métodos , Femenino , Hemobilia/terapia , Arteria Hepática/diagnóstico por imagen , Humanos , Incidencia , Masculino , Persona de Mediana EdadRESUMEN
The aim of this study was to describe the potential of three-dimensional ultrasound (3DUS) in the urinary tract of neonates, infants, and children. The potential applications are illustrated based on our experience in 80 patients using two different 3DUS techniques. Various disease entities throughout the neonatal and pediatric age have been evaluated. The potential of 3DUS is discussed based on comparison with conventional 2DUS or other imaging (as clinically indicated), focused on the potentially improved renal parenchymal volume assessment. In our experience, 3DUS is feasible in neonates, infants, and children without sedation. It reduces imaging time, improves demonstration of complex anatomy and allows for evaluation of anatomy/pathology in any plane. The 3DUS improves volume assessment and follow-up comparison by offering an improved standardization and documentation. Rendered views of the dilated collecting system enable a comprehensive demonstration of hydronephrosis similar to intravenous urography or MR urography images. Additionally, 3DUS offers an ideal tool for training and education. Yet, limitations have to be acknowledged: areas inaccessible for 2DUS; poor quality of the original 2DUS acquisition; limited resolution; patient motion and breathing; cardiac pulsation creating artifacts and misregistration; equipment cost; lack of 3D DICOM standards creating problems with data storage; as well as system-inherent technical limitations. Nevertheless, the 3DUS holds the potential to become a valuable additional imaging tool for sonographic evaluation of the pediatric urinary tract.
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Hidronefrosis/diagnóstico por imagen , Enfermedades Renales Quísticas/diagnóstico por imagen , Ultrasonografía Doppler en Color/métodos , Adolescente , Niño , Preescolar , Humanos , Hidronefrosis/patología , Imagenología Tridimensional , Lactante , Recién Nacido , Riñón/diagnóstico por imagen , Riñón/patología , Enfermedades Renales Quísticas/patología , Tamizaje Neonatal/métodos , Vejiga Urinaria/diagnóstico por imagen , Vejiga Urinaria/patologíaRESUMEN
This study compares amplitude-dependent speed of sound (AD-SoS) measured by phalangeal ultrasonography in a group of 60 patients with early rheumatoid arthritis (RA) with those who had had the disease for more than 4 years. The mean duration of the early disease group was 1.4 years, and the mean of the established RA group was 14.6 years. Plasma viscosity (PV), C-reactive protein (CRP) and HAQ scores were obtained. Forty-nine patients with early RA had hand radiographs assessed by the Larsen score method. The DBM Sonic system was assessed on normal volunteers and a coefficient of variation of 0.88% obtained. A significant correlation was found between the left and right hands of the patients groups studied ( r=0.84). The mean Z score of both hands was therefore used in comparing the two clinical groups. Results showed no correlation between CRP, PV and Z scores of AD-SoS. The HAQ scores showed a weak negative correlation, and there was no correlation between the Larsen score and Z score, or the number of swollen joints and Z score. However, the early and established groups with RA were significantly different (#E5/E5#=0.004). Within the early RA group the Z score for AD-SoS was lower in those with disease duration of less than 2 years (-1.71) than in those with disease duration of 2-4 years (-1.01). This suggests that bone loss in the fingers is greater in the first 2 years of disease than in the following 2 years, which might reflect an effect of treatment.
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Artritis Reumatoide/complicaciones , Osteoporosis/diagnóstico por imagen , Ultrasonografía/métodos , Absorciometría de Fotón , Adulto , Distribución por Edad , Anciano , Anciano de 80 o más Años , Análisis de Varianza , Artritis Reumatoide/diagnóstico , Enfermedad Crónica , Estudios de Cohortes , Femenino , Dedos/diagnóstico por imagen , Dedos/patología , Estudios de Seguimiento , Humanos , Persona de Mediana Edad , Osteoporosis/epidemiología , Osteoporosis/etiología , Prevalencia , Probabilidad , Factores de Riesgo , Sensibilidad y Especificidad , Índice de Severidad de la Enfermedad , Estadísticas no Paramétricas , Factores de Tiempo , Reino UnidoRESUMEN
BACKGROUND: We assessed mirror visual feedback (MVF) to test the hypothesis that incongruence between motor output and sensory input produces complex regional pain syndrome (CRPS) (type 1) pain. METHODS: Eight subjects (disease duration > or =3 weeks to < or =3 yr) were studied over 6 weeks with assessments including two controls (no device and viewing a non-reflective surface) and the intervention (MVF). Pain severity and vasomotor changes were recorded. RESULTS: The control stages had no analgesic effect. MVF in early CRPS (< or =8 weeks) had an immediate analgesic effect and in intermediate disease (< or =1 yr) led to a reduction in stiffness. At 6 weeks, normalization of function and thermal differences had occurred (early and intermediate disease). No change was found in chronic CRPS. CONCLUSIONS: In early CRPS (type 1), visual input from a moving, unaffected limb re-establishes the pain-free relationship between sensory feedback and motor execution. Trophic changes and a less plastic neural pathway preclude this in chronic disease.
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Retroalimentación Psicológica , Distrofia Simpática Refleja/terapia , Percepción Visual , Adulto , Temperatura Corporal , Femenino , Humanos , Pierna , Masculino , Movimiento , Umbral del Dolor , Proyectos Piloto , Distrofia Simpática Refleja/psicología , AutopsicologíaRESUMEN
The aim of this study was to evaluate the feasibility and diagnostic potential of dynamic MR urography (MRU) in neonates and infants with sonographically detected abnormalities of the upper urinary tract. Thirty infants (age range 5 days to 3 years, mean age 7.9 months; male:female: 22:8) underwent MRU using T2 and contrast-enhanced dynamic T1-weighted sequences. The results were compared with the findings of ultrasound ( n=30), intravenous urography (IVU, n=19) and/or scintigraphy ( n=25) based on the criteria suggestive of obstructive uropathy. Oral sedation was sufficient to perform MRU with diagnostic quality in 20 of 21 patients younger than 1 year; 9 older patients needed intravenous sedation. Diagnosis of the 66 renal units (58 kidneys, 29 successful examinations) included normal systems (contralateral units), duplex systems, vesico-ureteral reflux, obstructive megaureter, ureteropelvic junction obstruction and accompanying renal parenchymal disease, with complex pathology in 10 patients. Magnetic resonance urography demonstrated anatomy better than IVU, particularly the renal parenchyma, (ectopic) ureters, and poorly functioning dilated systems. Magnetic resonance urography was superior to US in showing ureteral pathology. Tiny cysts in dysplastic kidneys were better seen by US. Gadolinium-enhanced dynamic MRU allowed accurate assessment of obstruction applying IVU criteria. Here MRU matched IVU results, and most of the scintigraphic findings. Magnetic resonance urography can be performed in young infants with diagnostic quality using oral sedation. Magnetic resonance urography correctly depicts anatomy and allows assessment of the urinary tract better than US and IVU, with additional functional information. Magnetic resonance urography thus has the potential to replace IVU for many indications.
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Imagen por Resonancia Magnética , Sistema Urinario/anomalías , Estudios de Factibilidad , Humanos , Lactante , Recién Nacido , Imagen por Resonancia Magnética/métodos , Estudios Prospectivos , Cintigrafía , Ultrasonografía , Uréter/anomalías , Sistema Urinario/diagnóstico por imagen , Urografía , Reflujo Vesicoureteral/diagnósticoRESUMEN
Certain diseases cause permanent changes to the shapes and densities of nailfold capillaries and, therefore, nailfold capillaroscopy is important as a tool for diagnosing and monitoring these diseases. The first aim of the project is to resolve differences in terminology that have developed over the years in previous work. We propose a taxonomy for nailfold capillaries that cover six descriptive classes: cuticulis, open, tortuous, crossed, bushy, and bizarre. The first three are parametric in that they may be distinguished by the ratio of capillary length to width and by the curvature of the capillary limbs. The last three are characterized by their topology; a crossed capillary has a closed area that is not connected to the image background. Bushy and bizarre capillaries have atypical shapes that are characterized by the convex hull of their skeleton. These descriptive classes may be modified according to anomalies in width and length. The second aim is to automate the classification of capillaries by encapsulating the taxonomy in an algorithm; our computer program rivals the most experienced clinicians in classifying capillaries consistently with an overall agreement of 85% with the clinicians' majority view. This was particularly valuable in classifying borderline shapes objectively and consistently.
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Capilares/anatomía & histología , Uñas/irrigación sanguínea , Capilares/patología , Clasificación , Humanos , Angioscopía Microscópica , Terminología como AsuntoRESUMEN
The aim of our study was to assess the ability of amplitude coded-colour Doppler sonography (ACDS) to depict altered perfusion in paediatric renal disease in a prospective study. Colour Doppler sonography (CDS) and ACDS examinations were performed in 180 renal units (90 patients; age range newborn to 16 years) with unilateral or bilateral renal disease (e.g. reflux nephropathy, renal scars, end-stage renal disease, ureteropelvic junction obstruction, urinary tract infection, renal failure, haemolytic uraemic syndrome, nephrotic syndrome, systemic lupus erythematosus (LE), renal biopsy, congenital dysplasia, tumour/infiltration). The ACDS results were compared with scintigraphy or CT as well as to clinical findings. Amplitude colour-coded Doppler sonography accurately demonstrated normal vasculature in 49 of 51 healthy kidneys (= 96%); 3 healthy kidneys could not be evaluated due to motion/artefacts. In 39 of 43 kidneys with focally altered perfusion ACDS could be performed and correctly depicted focally impaired vasculature/perfusion in 35 kidneys (= 89.7%). Seventy-three of 83 kidneys with diffusely impaired perfusion could be evaluated by ACDS and altered pattern was correctly depicted in 58 kidneys (= 79.4%), with an overall percentage of agreement of 87.1%. Amplitude CDS appears to be useful in infants and children. Compared with CDS it improves visualisation of especially focally impaired vasculature/perfusion and should be considered a valuable adjunct to conventional investigations.
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Enfermedades Renales/diagnóstico por imagen , Ultrasonografía Doppler en Color , Adolescente , Niño , Preescolar , Femenino , Humanos , Lactante , Recién Nacido , Masculino , Estudios Prospectivos , Ultrasonografía Doppler en Color/métodosRESUMEN
Biofuels, such as brash from forest fellings, have been proposed as an alternative energy source. Brash removal may affect the sustainability of forest production, e.g., through a change in the availability of cations and N in the soil. We report initial effects of brash removal on inorganic N content in humus and mineral soil, soil-solution chemistry, and field-layer biomass after clear felling an N-fertilisation experiment in central Sweden. The experiment comprised six different fertiliser levels, ranging from 0 to 600 kg N ha(-1). Urea was given every 5th year during 1967 to 1982 to replicated plots, giving total doses of 0 to 2400 kg N ha(-1). Clear felling took place in 1995, 13 years after the last fertilisation. The removal of brash decreased the NO3- content in the humus layer after clear felling. A decrease in the NO3- concentration of the soil solution was indicated during most of the study period as well. No effect of the previous N fertilisation was found in the humus layer, but in the mineral soil there was an increase in NO3- content for the highest N dose after clear felling ( p = 0.06). The soil-solution chemistry and the field-layer biomass showed an irregular pattern with no consistent effects of brash removal or previous fertilisation.
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Biomasa , Nitrógeno/metabolismo , Suelo/análisis , Agricultura/tendencias , Agroquímicos/química , Agroquímicos/metabolismo , Cationes/química , Cationes/metabolismo , Fuentes Generadoras de Energía , Fertilizantes/análisis , Minerales/química , Minerales/metabolismo , Nitrógeno/química , Compuestos de Nitrógeno/química , Proyectos de Investigación , Soluciones/química , Suecia , Árboles/crecimiento & desarrollo , Árboles/metabolismoRESUMEN
UNLABELLED: Multicystic segmental renal dysplasia is rare in early childhood. We report a case with prenatally recognized renal malformation. Prenatally a cystic renal malformation was detected sonographically; postnatally further evaluation was performed by Doppler sonography, contrast enhanced CT and voiding cysto-urethrography leading to the diagnosis of a multicystic segmental nephroma. Due to increasing size in spite of therapeutic and diagnostic sonographic guided punctures and the atypic manifestation the baby underwent heminephrectomy. The final histological diagnosis confirmed preoperativ findings. CONCLUSION: Prenatally recognised cystiform renal malformations should be reevaluated postpartally by ultrasound and--as doubtful findings are found--further imaging might be necessary for follow up and for the decision on conservative or operative treatment.
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Neoplasias Renales/congénito , Tumor de Wilms/congénito , Adulto , Diagnóstico Diferencial , Femenino , Humanos , Recién Nacido , Neoplasias Renales/diagnóstico , Neoplasias Renales/cirugía , Nefrectomía , Embarazo , Tomografía Computarizada por Rayos X , Ultrasonografía Prenatal , Urografía , Tumor de Wilms/diagnóstico , Tumor de Wilms/cirugíaRESUMEN
PURPOSE: To assess the safety and efficacy of endovascular repair of abdominal aortic aneurysm in high-risk patients during the short to intermediate term. MATERIALS AND METHODS: Endovascular aneurysm repair was performed in 50 patients considered too high risk for conventional repair. Stent-grafts were inserted through surgically exposed femoral arteries with fluoroscopic guidance. The anesthetic technique was epidural in 36 patients, general in 12, and local in two. Aortouniiliac stent-grafts were inserted in 42 patients and aortoaortic in eight. RESULTS: There were no deaths and no conversions to open surgical repair. The primary success rate (complete aneurysm exclusion according to CT criteria) was 88% (44 of 50). The secondary, clinical, and continuing success rates were all 98% (49 of 50). Surgical time was 196 minutes +/- 67 (mean +/- SD), blood loss was 284 mL +/- 386, and volume of contrast material administered was 153 mL +/- 64. The time from the end of the surgery to resumption of a normal diet was 0.58 days +/- 0.56, to ambulation was 1.22 days +/- 0.77, and to discharge from the hospital was 3.63 days +/- 1.60. Wound problems accounted for the majority of complications. There were no instances of pulmonary failure, renal failure, stent-graft migration, or late leakage. CONCLUSION: Endovascular repair of abdominal aortic aneurysm is feasible in two-thirds of high-risk patients, with a low mortality and high success rate during the short to intermediate term.
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Aneurisma de la Aorta Abdominal/cirugía , Implantación de Prótesis Vascular , Stents , Anciano , Anciano de 80 o más Años , Aneurisma de la Aorta Abdominal/diagnóstico por imagen , Aneurisma de la Aorta Abdominal/epidemiología , Prótesis Vascular , Femenino , Humanos , Masculino , Persona de Mediana Edad , Diseño de Prótesis , Radiografía Intervencional , Factores de Riesgo , Factores de Tiempo , Resultado del TratamientoRESUMEN
PURPOSE: To assess the effect of transcatheter embolization for treatment of biopsy-related vascular injury in renal allografts, specifically evaluating technical success, clinical benefit, and long-term effect on renal function. MATERIALS AND METHODS: A retrospective review was performed of all postbiopsy renal allograft vascular injuries referred for embolization during a 113-month period. The likelihood of a prolonged detrimental effect on allograft function was estimated from observed variation in serum creatinine levels before and after the procedure. RESULTS: Embolic therapy with use of metallic coils and superselective technique was performed in 21 renal transplant patients. Technical success was achieved in 95% of cases. There were no serious complications. Eradication of the clinical sign or symptom prompting referral was seen in 15 of 17 (88%) patients. Eleven of 19 (58%) patients analyzed demonstrated no evidence of a long-term detrimental effect on allograft function. A detrimental effect was possibly present in six of 19 (32%) patients, and probable in only two of 19 (10%) patients. CONCLUSIONS: Transcatheter embolization can be an appropriate and effective therapeutic choice for biopsy-related renal allograft vascular injury.
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Biopsia/efectos adversos , Embolización Terapéutica/métodos , Trasplante de Riñón/patología , Arteria Renal/lesiones , Venas Renales/lesiones , Adolescente , Adulto , Aneurisma Falso/etiología , Aneurisma Falso/terapia , Angiografía , Fístula Arteriovenosa/etiología , Fístula Arteriovenosa/terapia , Cateterismo Periférico , Creatinina/sangre , Embolización Terapéutica/instrumentación , Femenino , Humanos , Trasplante de Riñón/fisiología , Estudios Longitudinales , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Trasplante Homólogo , Resultado del TratamientoRESUMEN
To assess the feasibility and advantages of functional motion-mode (M-mode) sonography in pediatric patients with various non-cardiac M-mode applications, 50 patients aged 6 days to 14.5 years with megaureter, diaphragmatic palsy and spinal cord malformation were studied. In addition to initial conventional brightness-mode gray-scale ultrasound. M-mode sonography was performed for evaluation of motion and possible impairment. The findings were compared with other imaging results. The impact of the sonographic results on clinical management was evaluated retrospectively. Impaired motion was demonstrated by conventional sonography in all cases. Only M-mode sonography enabled adequate documentation for comparison with follow-up examinations, but allowed only semiquantitative assessment. Thus even gradual improvement or deterioration can be followed in an unbiased way by using a better-documented investigation for comparison, though an objective 'ranking', especially of diaphragmatic movement, could not be achieved. M-mode sonography enables a non-invasive and non-ionizing evaluation and documentation of motion impairment in pediatric patients. It improves documentation of motion and enables a better comparison with previous findings. It is especially useful for follow-up in evolving disease.