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Con el propósito de evaluar la capacidad de tecnecio-99m metoxi-isobutil-isonitrilo (Tc99m -MIBI) para predecir la evolución de mujeres enviadas para evaluación de dolor precordial, se estudiaron las tasas de sucesos cardiovasculares al año en un grupo de pacientes con gammagrafía normal (grupo 1: 17 pacientes) y en otro con defectos de perfusión reversible (grupo 2: 17 pacientes). Se aplicó el protocolo de un día para la gammagrafía con Tc99m -MIBI (reposo/estrés), con estrés combinado (bicicleta ergométrica más 0,28 mg/kg de dipiridamol) en los casos en que fue necesario. Se hizo análisis cualitativo y cuantitativo de la captación regional. Las pacientes del grupo 1 eran más jóvenes que las del grupo 2 (edad promedio: 49 vs 55 años, respectivamente, p=0,04); y también tuvieron menos hipercolesterolemia (12 % vs 59 %, respectivamente, p=0,01). Se calcularon las tasas de aparición de sucesos cardiovasculares al año para las pacientes del grupo 2 usando el método de Kaplan.-Meier. Las tasas de aparición de sucesos clínicos (infarto miocárdico y angina inestable) y de necesidad de procedimientos de revascularización (angioplastia coronaria transluminal percutánea y cirugía de bypass aortocoronario) fueron 0,24 en ambos casos. Solo una paciente del grupo 1 presentó angina variante a los 5 meses. No hubo muertes en ninguno de los grupos. El 94 % de las pacientes con gammagrafía de perfusión normal estuvo libre de eventos al año de seguimiento, mientras que solo el 53 % de aquellas con defectos reversibles de perfusión mostraron igual comportamiento. Concluimos que la gammagrafía de perfusión miocárdica con Tc99m -MIBI es un instrumento útil para predecir la evolución al año de mujeres referidas para evaluación de dolor precordial.In order to evaluate the capacity of myocardial perfusion scintigraphy with Tc99m-MIBI to predict the evolution of women referred for evaluation of precordial pain, the rates of cardiovascular events at one year were studied in a group of patients with normal scintigraphy (group 1: 17 patients) and in another with reversible perfusion defects (group 2: 17 patients). The one-day protocol was applied for scintigraphy with Tc99m-MIBI (rest/stress) with combined stress (ergometric bicycle plus 0.28 mg/Ig of dipyridamole) in those cases where it was necessary. A quantitative and qualitative analysis of the regional uptake was made. Patients from group 1 were younger than those from group 2 (average age: 49 vs 55, respectively, p = 0.04) and they had less hypercholesterolemia (112 % vs 59 %, respectively, p = 0.01). The rates of appearance of cardiovascular events at one year were calculated for patients from group 2 by using the Kaplan-Meier's method. The rates of appearance of clinical events (myocardial infarction and unstable angina) and of revascularization procedures (percutaneous transluminal coronary angioplasty and aortocoronary bypass surgery) were 0.24 in both cases. Only a patient from group 1 presented varying angina at 5 months. No deaths were reported in any of the groups. 94 % of the patients with normal perfusion scintigraphy were free of events after a one-year follow-up, whereas only 53 % of those with reversible perfusion defects showed a similar behavior. It was concluded that myocardial perfusion scintigraphy with Tc99m-MIBI is a useful tool to predict the evolution of women referred for evaluation of precordial pain at one year.

Se compararon los resultados de la gammagrafía con tecnecio 99m- metoxi-isobutil-isonitrilo en protocolo de un día: reposo-estrés físico o combinado (bicicleta más dipiridamol endovenoso), con los de la angiografía coronaria, en 20 mujeres remitidas para evaluación de dolor precordial y de la utilidad de la gammagrafía de perfusión miocárdica en el diagnóstico de la enfermedad coronaria en la mujer. La captación del radiofármaco en estrés y reposo varió de: 93 ± 9 a 94 ± 7 % en los 204 segmentos con captación normal en estrés; 67 ± 9 a 75 ± 17 % en los 89 con moderada reducción y 33 ± 9 a 64 ± 28 % en los 27 con severa reducción. Los análisis cualitativo y cuantitativo de la captación coincidieron en 18 pacientes. La gammagrafía de perfusión y la angiografía concordaron en el 70 % de las pacientes. Se concluyó que la gammagrafía de perfusión miocárdica con Tc 99m-MIBI contribuye al diagnóstico de la enfermedad coronaria en mujeres.The results of technetium 99m - methoxy-isobutyl-isonitril scintigraphy in a one-day protocol: rest - physical or combined stress (bicycle plus endovenoous dipiridamole) were compared with those of coronary angiography in 20 women referred for the evaluation of precordial pain and of the usefulness of myocardial perfusion scintigraphy. The uptake of the radiodrug under stress and at rest varied from 93 ± 9 to 94 ± 7 % in the 204 segments with normal uptake under stress, from 67 ± 9 to 75 ± 17 % in the 89 with moderate reduction, and from 33 ± 9 to 64 ± 28 % in the 27 with severe reduction. The qualitative and quantitative uptake analyses coincided in 18 patients. The perfusion scintigraphy and the angiography agreed in 70 % of the patients. It was concluded that the myocardial perfusion scintigraphy with technetium 99-MIBI contributes to the diagnosis of the coronary artery disease in women.

Transthyretin cardiac amyloidosis (ATTR) is a restrictive cardiomyopathy that leads to heart failure in considerable number of patients. Early diagnosis allows specific treatment options. However, ATTR diagnosis is complex and requires invasive procedures. The utility of 99mTc-phosphate tracers for non-invasive diagnosis is well-known but the experience in Argentina is insufficient. The aim of this work was to assess the utility of 99m Tc-phosphate tracers for the diagnosis of ATTR. A total of 46 scintigraphies for detection of cardiac amyloidosis performed between September 2016 and January 2018 were analyzed. Cardiac retention after one hour was assessed in relation to bone uptake using two methods: A semi-quantitative visual score (grade 0 = absent, I = low II = moderate-III = high) and a quantitative method (heart/lung ratio). The final diagnosis and the amyloidosis subtype were carried out by our institution cardiomyopathy team according to international guidelines. The positive and negative predictive values for Grade ≥ II were 96% and 100% respectively for diagnosis of ATTR. Using 1.38 as cut-off value for heart/lung ratio the sensitivity and the specificity were 96% and 100%, respectively for differentiating transthyretin cardiac amyloidosis from light-chain cardiac amyloidosis and other cardiopathies. Scintigraphy with 99m Tc-phosphate tracers enable noninvasive diagnosis and subtype classification of cardiac amyloidosis. The use of this non-invasive, inexpensive and widely available tool will result in better patient management.

Introduction and Objective: Sentinel lymph node biopsy (SLNB) is the most useful tool for node staging in melanoma. SLNB facilitates selective dissection of lymph nodes, that is, the performance of lymphadenectomy only in patients with sentinel nodes positive for metastasis. Our aim was to assess the cost of SLNB, given that this procedure has become the standard of care for patients with melanoma and must be performed whenever patients are to be enrolled in clinical trials. Furthermore, the literature on the economic impact of SLNB in Spain is scarce., Method: From 2007 to 2010, we prospectively collected data for 100 patients undergoing SLNB followed by transhilar bivalving and multiple-level sectioning of the node for histology. Our estimation of the cost of the technique was based on official pricing and fee schedules for the Spanish region of Murcia., Results: The rate of node-positive cases in our series was 20%, and the mean number of nodes biopsied was 1.96; 44% of the patients in the series had thin melanomas. The total cost was estimated at between €9486.57 and €10471.29. Histopathology accounted for a considerable portion of the cost (€5769.36)., Discussion: The cost of SLNB is high, consistent with amounts described for a US setting. Optimal use of SLNB will come with the increasingly appropriate selection of patients who should undergo the procedure and the standardization of a protocol for histopathologic evaluation that is both sensitive and easy to perform., (Copyright © 2014 Elsevier España, S.L.U. and AEDV. All rights reserved.)

Sentinel lymph node biopsy is performed routinely in melanoma because lymph node progression has been shown to be the strongest predictor of survival. Given the proven relevance of biopsy findings in this type of skin cancer, the procedure has been extended to other skin tumors. Experience in nonmelanoma cancer is much more limited and the prognostic usefulness of biopsy results remains to be shown. This critical review of the literature on the various skin tumors in which sentinal node biopsy has been practiced discusses the usefulness of this procedure., (Copyright © 2010 Elsevier España, S.L. y AEDV. All rights reserved.)

Background: The asthmatic children who do not respond favorably to the specifically anti-allergic treatment, and also begin their breathlessness crisis preferably at night, are suspicious of suffering gastric-esophagus reflux that stimulate bronchial spasm crisis by means of an aspiration mechanism, or more frequently, by means of a reflective mechanism through the vagal via., Objectives: To know probable physiopathologic mechanism of gastric-esophagus reflux that exacerbates asthmatic crisis. To know digestive symptoms associated to respiratory process. To evaluate clinic evolution of children after antireflux treatment., Material and Methods: There were chosen 50 moderate-severe persistent asthmatic patients with non favorable evolution and gastric-esophagus reflux. The diagnosis was settled by means of radiological study, with barium contrast in esophagus, stomach and duodenum, and esophagus-pulmonary gammagraphy with technetium 99 (99mTc). Besides, a searching of bronchial aspiration signs with the isotopic exploration was carried out., Results: It was demonstrated that 38% of all cases had bronchial microaspirations and 30% did not have digestive symptoms associated to the respiratory process. Patients were subjected to an antireflux treatment and 78% of them considerably improved their asthmatic crisis after the treatment., Conclusions: 38% of the cases showed bronchial microaspirations in pulmonary gammagraphy. The more probable physiopathologic mechanism was vagal via, because 62% of the patients did not have bronchial aspiration signs. There were no digestive symptoms (silent reflux) in 30% of the children. Asthmatic crisis evolved favorably in 78% of the cases after antireflux treatment.

The 3 foundations of nuclear medicine are radiation conscious personnel, specific radiopharmaceuticals and equipment. The trend in molecular radiopharmacy is to develop new radiopharmaceuticals targeting peptides and receptors. 99mTc-radiopharmaceuticals give important clinical and molecular information especially in endocrinology, oncology and cardiology. The basic equipment has relied on crystal scintillation detector gamma cameras and the obtained images represent organ function provided by the specific radiopharmaceutical. Gamma cameras for single emission computed tomography (SPECT) can be added to an X-ray computed tomography (CT) equipment to form a hybrid (SPECT/ CT). The system is coupled to computer algorithms and special software to acquire and process the separate studies and fuse the two images to give a 3-D image of organ function plus anatomy. The new semiconductor or solid state detectors are a big improvement in commercial hybrid scintillation cameras and micro-SPECT/CT. Fused images obtained with SPECT/CT have been very useful in almost all medical areas and play an important role in preclinical research. The aim of this work is to present the current status and future trends of SPECT/CT systems in the clinical practice of nuclear medicine using technetium-99m radiopharmaceuticals. The development of molecular, functional and genetic imaging tools aided by new technology and SPECT/CT image fusion will enhance accurate diagnoses, and understanding of molecular mechanisms of disease and their respective response to radiopharmaceutical therapy.

Most patients with invasive squamous cell carcinoma of the penis do not have inguinal node metastasis at the time of diagnosis and 50% of those having palpable nodes are inflammatory. Penis cancer (PC) treatment implies resection of the primary tumor and inguinal lymphadenectomy; nevertheless, morbidity related to this procedure is high and its usefulness may be questioned in patients without metastasis in dissected nodes. Lymphatic mapping with sentinel node biopsy (LMSNB) is a valid alternative, useful in other neoplasias. The objective of this study is to determine if it is possible to identify a sentinel node (SN) in patients with PC. Patients with T1-2 PC without palpable nodes (N0) were included. LMSNB was carried out with the combined technique (blue dye and radiocolloid). All patients underwent an elective bilateral inguinal lymphadenectomy. Sensitivity and false negative index were calculated. SNs were sent for transoperative study with imprint technique and, definitively, with serial cuts and hematoxylin/eosin staining. Nine patients showed results with 32 lymph carrier zones and SN was identified in all of them, 4 regions had metastasis, in 3 the SN was metastatic and in one patient was metastasis-negative (false negative); sensitivity = 80%; false negatives index = 20%. Seven patients (77%) did not have node metastasis. LMSNB is an alternative for staging PC patients and could prevent unnecessary inguinal lymphadenectomies. A larger number of patients is required to validate the sturdy. The combined technique offers a high rate of success in SN identification.

The procedure of sentinel node biopsy has been used previously in clear cell sarcoma. There are few studies reported. Due to the similar biological features with melanoma, this procedure can be effective. Sentinel biopsy is an option to detect nodal subclinical metastases. A 19-year-old man presented with ulcerated lesion in the fifth finger of the left hand. The biopsy reported clear cell sarcoma. Immunohistochemistry was positive for Vimentin and S-100. There was no evidence of regional disease. The sentinel lymph node biopsy, using patent blue and Tc-99 rhenium, was positive for metastases. Axillar dissection was carried out. The final report confirmed three metastasic nodes and the patient received adjuvant chemotherapy.

This paper presents the preparation of a radiocolloid that still makes it possible to label leukocytes using its phagocytosis capacity. Given that this function is exclusively of the white blood cells, not being exercised by other blood cells, the use of a stannous fluoride radiocolloid labeled with 99mTc (F2Sn-99mTc) was tested in order to label leukocytes in whole blood samples. Using cellular separation techniques in density gradients and acquisition of images in gamma camera of radioactivity distribution in Percol, it was observed that the white cells labeling achieved was selective and with high efficiency for leukocytes (in all cases, it was superior to 70%), optimal reproducibility, low cost and low cellular toxicity.

We have studied 26 patients (32-77 years old, 16 females) with suspicion of joint arthroplasty infection: 11 total hip replacements, 12 total knee replacements and 3 osteosinthesys. A bone scintigraphy with MDP-99mTc, a scintigraphy with HMPAO-WBC and a scintigraphy with 99mTc-stannous colloid were made in all patients. The final diagnostic was based in joint cultures and clinic and radiologic evolution of the patients. The earliest phase of the bone scintigraphy was positive in 18 patients. The later phase was positive in all them. The WBC was positive in 20 out of 26 patients. The bone marrow scintigraphy showed a congruent pattern with WBC in 18 patients (17 infected and 1 without infection). The other ones (8 patients) showed an incongruent pattern (7 with infection and 1 without it). The results show that the bone marrow scintigraphy with 99mTc-stannous colloid improves the accuracy of the diagnostic of bone prosthesis infection and should be included into the diagnosis protocol of this disease.

The author writes about some facts related to the use of 99m-Tc-phosphate in skeletal scanning, specially to recognize cancer metastases, and vascular and inflammatory osseous diseases, and indicates some conditions to carry out the study.