RESUMEN
Isotope bone scans have been used for a number of years to assess growth activity in the mandibular condyle in patients who present with facial asymmetry. The aim is to distinguish normal bone growth within the condyle from increased activity that may be the cause of the asymmetry. Previous studies have, however, relied only on planar images. SPECT (single photon emission computed tomography) has been used with quantitative assessments of one mandibular condyle to clivus or lumbar spine, but we have compared one condyle with the other, which is more sensitive and accurate in detecting abnormal activity. A relative percentage uptake of 55% or more in the affected mandibular condyle is considered to be abnormal, and this has been validated by comparison with an age-matched control group. We have used SPECT as an aid to diagnosis and treatment in 18 patients with asymmetrical growth and have constructed a therapeutic algorithm to aid the treatment of these patients.
Asunto(s)
Cóndilo Mandibular/diagnóstico por imagen , Tomografía Computarizada de Emisión de Fotón Único , Adolescente , Adulto , Estudios de Casos y Controles , Niño , Fosa Craneal Posterior/diagnóstico por imagen , Asimetría Facial/complicaciones , Asimetría Facial/diagnóstico por imagen , Asimetría Facial/fisiopatología , Asimetría Facial/cirugía , Femenino , Estudios de Seguimiento , Humanos , Hiperplasia , Vértebras Lumbares/diagnóstico por imagen , Masculino , Maloclusión/etiología , Maloclusión/cirugía , Cóndilo Mandibular/crecimiento & desarrollo , Cóndilo Mandibular/patología , Cóndilo Mandibular/cirugía , Osteotomía , Radiofármacos , Reproducibilidad de los Resultados , Medronato de Tecnecio Tc 99mRESUMEN
In severe chronic heart failure (CHF) the ventilatory cost of CO2 elimination during exercise (VE/VCO2) is increased, suggesting ventilation/perfusion (V/Q) mismatch. The relationship of exercise VE/VCO2 regression slope m to deadspace ventilation was studied in 15 patients with CHF who underwent cardiopulmonary exercise testing and arterial blood gas monitoring. Regional lung ventilation and perfusion was studied, using 133xenon, at rest and peak exercise in a further group of 10 CHF patients and in five normal subjects. VE/VCO2 slope m correlated well with deadspace ventilation at peak exercise in the 15 patients with CHF. We therefore used exercise VE/VCO2 slope m to categorize CHF patients undergoing 133xenon imaging into groups with increased (slope m > 36) or normal (slope m < 36) exercise deadspace ventilation. In normals, resting V/Q determined by 133xenon showed a gravitational gradient, which improved on exercise as a result of relative increases and of relative reductions in regional perfusion; no significant changes in regional ventilation distribution were detected. In patients with CHF who had normal slope m (n = 5), rest and exercise V/Q were similar to the normal subjects. In CHF patients with increased slope m (n = 5) however, the resting gravitational gradient of V/Q was lost, and there were no significant changes in relative perfusion distribution on exercise. These findings suggest that the increased ventilatory cost of CO2 elimination found in certain patients with CHF is related to inability to coordinate and optimise the relative distribution of lung perfusion with respect to ventilation during exercise.
Asunto(s)
Insuficiencia Cardíaca/diagnóstico por imagen , Insuficiencia Cardíaca/fisiopatología , Ventilación Pulmonar , Radioisótopos de Xenón , Adulto , Dióxido de Carbono/metabolismo , Prueba de Esfuerzo , Insuficiencia Cardíaca/sangre , Humanos , Masculino , Persona de Mediana Edad , Oxígeno/sangre , CintigrafíaRESUMEN
Ten male volunteers were studied in a randomized, double-blind crossover trial. Each received ketorolac tromethamine 30 mg and morphine sulphate 10 mg i.m. at an interval of 2 weeks. After a standard radiolabelled meal, gastric emptying half-time (GE) and small intestinal transit time (SIT) were measured using a gamma camera. Small intestinal transit time was measured also from end-tidal breath hydrogen (ETH), and overall gastrointestinal motility by time to first flatus (TFF). Mean GE, SIT and TFF were significantly prolonged by morphine compared with ketorolac (P less than 0.03); ETH was prolonged also, but the difference was not significant. There were no significant correlations between SIT, ETH and TFF. Most subjects reported adverse effects after morphine, but only one after ketorolac.