IJCS | Volume 32, Nº2, May/June 2019

DOI: 10.5935/2359-4802.20180103 Abstract This paper is about the Guideline for Ventilation / Perfusion Scintigraphy. It has been developed by the Brazilian Society of Nuclear Medicine to be a best practices guide used in Nuclear Medicine. Its function is to be an educational tool to help the Nuclear Medicine Services in Brazil to guarantee a quality care to the patients. Introduction This guideline presents the best practices for carrying out and interpretingVentilation / Perfusion Scintigraphy. The main indication for Ventilation / Perfusion Scintigraphy is the detection of acute pulmonary thromboembolism (PE). It is characterized by acute obstruction of a pulmonary artery, or one of its sub- branches, caused by venous thrombus. The typical picture includes symptoms such as dyspnea without other cause, chest pain on inspiration and hemoptysis, accompanied by signs of low blood oxygen saturation and tachycardia. Loss of consciousness, hemodynamic instability and death may occur in more severe cases. 1 The American College of Radiology (2011) guideline classifies Ventilation / Perfusion Scintigraphy as highly recommended, combined with CT pulmonary angiography (CTPA). Both studies are highly accurate in the diagnosis of acute PE and the choice for one or the other will depend on the availability of each service and may follow some specific recommendations, as in the case of patients with allergy to iodinated contrast or renal failure, in which scintigraphy should be preferred. 2 If adequately used and interpreted, ventilation / perfusion scintigraphy is an important tool for the detection of regional abnormality of pulmonary perfusion and ventilation, allowing for the accurate diagnosis of pulmonary embolism with low radiation exposure and minimum risks of complications. Objectives The purpose of this guideline is to provide practical guidance on the indication, performance and interpretation of the results of Ventilation / Perfusion Scintigraphy. General information about the exam It is an imaging diagnostic procedure that uses ventilation and perfusion scintigraphy to assess pulmonary diseases. Indications The main indications for ventilation / perfusion scintigraphy are listed on Table 1. Relative contraindication Pregnancy and breastfeeding. One should weight the cost/benefit and, if the procedure has to be performed, it should be done in such a way that exposure to radiation be minimized and, whenever possible, it would be preferable to carry out only the perfusion phase. It is worth noting that, in pregnant women with suspected pulmonary embolism and normal chest X-ray, the American Thoracic Society and the Society of Thoracic Radiology Clinical Practice recommend the use of 302 GUIDELINE International Journal of Cardiovascular Sciences. 2019;32(3)302-309 Mailing Address: Marcel Yanagihara Rigolon Rua Gilberto Pattaro, 150, casa 61. Postal Code: 13084-375, Residencial Burato, Campinas, SP - Brazil. E-mail: marcel.rigolon@gmail.com, marcelyg@hotmail.com Guideline for Ventilation / Perfusion Scintigraphy Marcel Yanagihara Rigolon, 1 C laudio Tinoco Mesquita, 2 B árbara Juarez Amorim 1 Universidade Estadual de Campinas (Unicamp), 1 Campinas, SP - Brazil Universidade Federal Fluminense, 2 Rio de Janeiro, RJ - Brazil Manuscript received February 20, 2018; revised manuscript May 28, 2018; accepted June 07, 2018. Pulmonary Embolism/complications; Pulmonary Embolism/diagnostic imaging; Ventilation-Perfusion Ratio; Pulmonary Artery/pathology; Radionuclide Imaging/methods. Keywords