Tomographic analysis by three-dimensional reconstruction of bronchical stenoses after pulmonary transplantation

• Grant number: 17/05421-5
• Support Opportunities: Scholarships in Brazil - Scientific Initiation
• Start date: September 01, 2017
• End date: August 31, 2018
• Field of knowledge: Health Sciences - Medicine - Surgery
• Principal Investigator: Marcos Naoyuki Samano
• Grantee: Yuri Tebelskis Nunes Dias
• Host Institution: Instituto do Coração Professor Euryclides de Jesus Zerbini (INCOR). Hospital das Clínicas da Faculdade de Medicina da USP (HCFMUSP). Secretaria da Saúde (São Paulo - Estado). São Paulo , SP, Brazil

Abstract

Airway complications in lung transplants remain one of the main factors in increasing morbidity and mortality. It is estimated that bronchial stenosis can occur in up to 27% of patients undergoing lung transplantation, of whom 13% require interventional bronchoscopy to treat such complications. It is believed that this complication is of multifactorial origin, being associated with acute rejection, reduction of vascularization of the anastomosis and increased expression of genes linked to hypoxia. Bronchial stenosis after lung transplantation may appear weeks or months after transplantation and there is as yet no objective diagnostic method that does not require endoscopic skills and is widely accepted. Thus, the objective of this project is to create a numerical index to assess the degree of stenosis based on a non-invasive method based on a three-dimensional reconstruction of the airway from computed tomography (CT). CT images will be analyzed using the CPR tool of the Aquarius Intuition software of the company TERARECON, which is currently used for the analysis of coronary stenosis. This software is capable of tracing a virtual line through the center of the structure and calculating the cross-sectional area at any point in the structure that the operator indicates. In this way, three measurements of cross-sectional areas of the bronchus will be obtained: 5 mm upstream at the site and 5 mm downstream of the anastomosis, and then calculate the ratio, here called the Anastomosis Index (AI), between the areas of the anastomosis and the arithmetic mean of the proximal and distal sectional areas and we will compare the relation of this ratio with the clinical and bronchoscopic diagnosis of bronchial stenosis. As an application of the Thales Theorem, the AI is expected to be close to 1 in individuals without bronchial stenosis and less than 1 in individuals with stenosis. (AU)