[Usefulness of thyroid scintigraphy in the therapeutic management of amiodarone-induced hyperthyroidism]. / Utilidad de la gammagrafía tiroidea en el manejo terapéutico del hipertiroidismo inducido por amiodarona.

UNLABELLED: Amiodarone-induced hyperthyroidism is relatively common in iodine-deficient regions. Two types have been described: type I, caused by increased synthesis and release of thyroid hormone in individuals with underlying thyroid disease, can be treated with antithyroid drugs or radioiodine; and type II, a destructive thyroiditis responsive to corticoid therapy but not to antithyroid drugs. It can be difficult to distinguish between the two types, and cases of mixed types have been reported. OBJECTIVE: to assess the usefulness of thyroid scintigraphy in amiodarone-induced hyperthyroidism. MATERIALS AND METHODS: 27 consecutive patients (13 females) with amiodarone-induced hyperthyroidism. Mean age was 65 years (range: 39-89). All patients underwent 99mTc-pertechnectate thyroid scintigraphy and were classified according to the qualitative estimation of radiotracer uptake: type I (increased / normal uptake): 9 patients, all of whom responded to antithyroid drugs or radioiodine, except one patient with sub-clinical hyperthyroidism who received no therapy; type II (very low or undetectable uptake): 13 patients, 11 of whom responded to discontinuation of amiodarone or prednisone therapy (2 patients). Hyperthyroidism was resistant in 2 patients and required antithyroid drugs or potassium perchlorate; mixed type (low uptake but with underlying thyroid pathology): 5 patients, with variable evolution; all needed antithyroid drugs, one required subtotal thyroidectomy, and another radioiodine treatment. CONCLUSION: thyroid scintigraphy can establish the correct therapeutic approach in most cases of amiodarone-induced hyperthyroidism, making it essential in the clinical management of these patients.

Utilidad de la gammagrafía tiroidea en el manejo terapéutico del hipertiroidismo inducido por amiodarona / Usefulness of thyroid scintigraphy in the therapeutic management of amiodarone-induced hyperthyroidism

El hipertiroidismo por amiodarona (HA) es una entidad relativamente frecuente en zonas dietéticamente deficitarias de yodo. Se describen dos entidades: la tipo I, causada por excesiva síntesis de hormona tiroidea en pacientes con patología tiroidea subyacente que responde a antitiroideos o al radioyodo, y la tipo II, producida por tiroiditis destructiva inflamatoriaque responde a los corticoides, pero no a los antitiroideos. La diferencia entre ambos tipos puede ser difícil, y se han descrito formas intermedias. Objetivo. Valorar la utilidad de la gammagrafía tiroidea en pacientes con HA. Material y métodos. Veintisiete pacientes consecutivos (13 mujeres) con 39-89 años e HA. Se realizó gammagrafía tiroidea con 99mTc-pertecnectato, clasificando al paciente en subgrupos, en función de una valoración cualitativa de la captación gammagráfica. Resultados: patrón tipo I (captación tiroidea normal o incrementada): 9 pacientes. Todos respondieron a la terapia con antitiroideos o radioyodo, excepto un paciente con hipertiroidismo subclínico que no recibió tratamiento; patrón tipo II (captación inhibida): 13 pacientes. La mayoría (11 pacientes) remite al retirar la amiodarona (9) o con corticoides (2). Sólo en dos pacientes el hipertiroidismo fue resistente y obligó a la terapia con antitiroideos o perclorato potásico; patrón intermedio (5 pacientes) con captación empobrecida y patología tiroidea subyacente. Tuvieron una evolución variable, necesitando antitiroideos en todos los casos; además uno de ellos precisó tiroidectomía subtotal y otro tratamiento con radioyodo. Conclusiones. La gammagrafía tiroidea permite establecerla terapia a administrar en la mayoría de pacientes con HA, por lo que resulta una herramienta diagnóstica imprescindible en el manejo clínico de estos pacientes

Amiodarone-induced hyperthyroidism is relatively common in iodine-deficient regions. Two types have been described: type I, caused by increased synthesis and release of thyroid hormone in individuals with underlying thyroid disease, can be treated with antithyroid drugs or radioiodine; and type II, a destructive thyroiditis responsive to corticoid therapybut not to antithyroid drugs. It can be difficult to distinguish between the two types, and cases of mixed types have been reported.Objective. to assess the usefulness of thyroid scintigraphy in amiodarone-induced hyperthyroidism. Materials and methods. 27 consecutive patients (13 females) with amiodarone-induced hyperthyroidism. Mean age was 65 years (range: 39-89). All patients underwent 99mTcpertechnectate thyroid scintigraphy and were classified according to the qualitative estimation of radiotracer uptake: type I (increased / normal uptake): 9 patients, all of whom responded to antithyroid drugs or radioiodine, except one patient with sub-clinical hyperthyroidism who received no therapy; type II (very low or undetectable uptake): 13 patients, 11 of whom responded to discontinuation of amiodarone or prednisone therapy (2 patients). Hyperthyroidism was resistant in 2 patients and required antithyroid drugs or potassium perchlorate; mixed type (low uptake but with underlying thyroid pathology): 5 patients, with variable evolution; all needed antithyroid drugs, one required subtotal thyroidectomy, and another radioiodine treatment. Conclusion. thyroid scintigraphy can establish the correct therapeutic approach in most cases of amiodarone-induced hyperthyroidism, making it essential in the clinical management of these patients

[Quality assurance of the renal applications software]. / Control de calidad de las aplicaciones de procesado renal.

INTRODUCTION: The need for quality assurance of all technical aspects of nuclear medicine studies is widely recognised. However, little attention has been paid to the quality assurance of the applications software. Our work reported here aims at verifying the analysis software for processing of renal nuclear medicine studies (renograms). MATERIAL AND METHODS: The software tools were used to build a synthetic dynamic model of renal system. The model consists of two phases: perfusion and function. The organs of interest (kidneys, bladder and aortic artery) were simple geometric forms. The uptake of the renal structures was described by mathematic functions. Curves corresponding to normal or pathological conditions were simulated for kidneys, bladder and aortic artery by appropriate selection of parameters. RESULTS: There was no difference between the parameters of the mathematic curves and the quantitative data produced by the renal analysis program. CONCLUSION: Our test procedure is simple to apply, reliable, reproducible and rapid to verify the renal applications software.

Control de calidad de las aplicaciones de procesado renal / Quality assurance of the renal applications software

Objetivo. Todos los aspectos técnicos de los estudios de Medicina Nuclear deben ajustarse a un programa de garantía de calidad. Sin embargo, se ha prestado poca atención al control de calidad de las aplicaciones de procesado. Nuestro trabajo pretende verificar los programas de análisis empleados en el procesado de los estudios renales (renogramas). Material y métodos. Mediante software hemos construido un modelo dinámico sintético del sistema renal. El modelo consta de dos fases: perfusión y función. Los órganos de interés (riñones, vejiga y arteria aorta) fueron simulados mediante formas geométricas simples. Las captaciones de las estructuras renales vienen descritas por funciones matemáticas. Se simularon distintas curvas de actividad-tiempo de riñón, vejiga y arteria aorta correspondientes a situaciones normales y patológicas mediante la selección adecuada de parámetros. Resultados. No se ha observado ninguna diferencia entre los parámetros de las curvas matemáticas y los datos cuantitativos producidos por el programa de análisis renal. Conclusión. Nuestro procedimiento nos permite verificar los programas de procesado de los estudios renales de forma simple, fiable, reproducible y rápida

Introduction. The need for quality assurance of all technical aspects of nuclear medicine studies is widely recognised. However, little attention has been paid to the quality assurance of the applications software. Our work reported here aims at verifying the analysis software for processing of renal nuclear medicine studies (renograms). Material and methods. The software tools were used to build a synthetic dynamic model of renal system. The model consists of two phases: perfusion and function. The organs of interest (kidneys, bladder and aortic artery) were simple geometric forms. The uptake of the renal structures was described by mathematic functions. Curves corresponding to normal or pathological conditions were simulated for kidneys, bladder and aortic artery by appropriate selection of parameters. Results. There was no difference between the parameters of the mathematic curves and the quantitative data produced by the renal analysis program. Conclusion. Our test procedure is simple to apply, reliable, reproducible and rapid to verify the renal applications software

[99mTc-labelled antigranulocyte anibody fragment Fab scintigraphy (sulesomab, leukoscan) and three-phase bone scintigraphy in the study of painful hip and knee prosthesis]. / Gammagrafía con fragmentos Fab' antigranulocitos-99mTc (sulesomab, leukoscan) y ósea en tres fases en el estudio de las prótesis de cadera y rodilla dolorosas.

We aim to assess the diagnostic utility of the combination of a three phase bone scintigraphy (3FBS) and scintigraphy with Fab'antigranulocyte fragments-99mTc (Sulesomab, Leukoscan) in patients with painful joint replacements. We studied 29 patients (22 women and 7 men with mean age 64 years) with knee (15) and hip (14) prosthesis. Scintigraphy was performed with a Siemens Orbiter 75 gammacamera with all purpose collimator. 3FBS was performed as usual with 740 MBq of MDP-99mTc. Sulesomab images were obtained at 1 and 4 hours following injection of 740 MBq, with 300,000 cts per view (knee) and 500,000 cts per view (hip). Both scintigraphic studies were interpreted visually by two nuclear medicine physicians with a 0, 1, 2, 3 score corresponding to normal or mild, moderate or intense hyperactivity respectively. Interpretation criteria for bone infection was Sulesomab uptake grade 2 or 3 in a moderate or large sized area, with congruent hyperactivity on the bone scan. Grade 1 uptake with Sulesomab was considered nonspecific associated to nonseptic conditions. The frequent pattern of uptake in synovial femoral tissue (cap shape sign) in knee prosthesis was considered nonspecific. Diagnostic confirmation procedures were surgery and culture (9) and follow-up (20). All six septic joints were correctly identified. A false positive result was obtained in a case of mechanical loosening in the knee. Negative studies were very helpful in the exclusion of infection. Our conclusion is that sensitivity is high, 100%, and that a normal or grade 1 Sulesomab image makes the presence of infection improbable.

Gammagrafía con fragmentos Fab' antigranulocitos-99mTc (sulesomab, leukoscan) y ósea en tres fases en el estudio de las prótesis de cadera y rodilla dolorosas / 99Mtc-labelled antigranulocyte antibody fragment Fab' scintigraphy (sulesomab, leukoscan) and three-phase bone scintigraphy in the study of painful hip and knee prosthesis

Se pretende conocer el rendimiento diagnóstico de la combinación gammagrafía ósea en tres fases (GO3F) y con fragmentos Fab'antigranulocitos-99mTc (Sulesomab, Leukoscan®) en las artroplastias de cadera y rodilla dolorosas. Se han estudiado 29 pacientes (22 mujeres y 7 hombres, con edad media de 64 años) con artroplastias de rodilla (15) y de cadera (14). Se utilizó una gammacámara Siemens Orbiter 75 con colimador LEAP. La GO3F se realizó según protocolo convencional, con 740 MBq de MDP99mTc. La gammagrafía con Sulesomab-99mTc se obtuvo a 1 h y 4 h p.i. de 740 MBq a 300.000 cts (rodilla) y a 500.000 (cadera). Dos médicos nucleares valoraron visualmente ambos estudios asignando un score de 0, 1, 2 y 3 correspondiente a normal, hiperactividad leve, moderada e intensa respectivamente. El criterio de interpretación para infección ósea fue una captación con Sulesomab de grado 2 ó 3 en un área de tamaño moderado o extenso coincidiendo con hiperactividad en la gammagrafía ósea. Se permitió una captación grado 1 con Sulesomab como inespecífica y asociada a procesos no sépticos. En la rodilla se reconoció el frecuente patrón de captación en tejido sinovial femoral (cap shape sign) inespecífico. La confirmación diagnóstica fue con cirugía y cultivos (9) y seguimiento clínico (20). Se detectaron los 6 procesos sépticos y se obtuvo un falso positivo en un aflojamiento simple de rodilla. Los estudios negativos fueron muy útiles para descartar infección. Concluimos que la sensibilidad es alta 100 per cent y que un estudio con Sulesomab normal o grado 1 hace improbable la presencia de infección. (AU)