Quantification of Pneumothorax Volume on Chest X-Ray: A More Accurate Index Based On Measurements Made With 3D-printed Models.

PURPOSE: Owing to the extent of lung collapse estimated on chest radiograph it is still the complementary test most commonly used in the management of patients with pneumothorax. There are several indices to assess the extent of lung collapse. The objective of this study was to develop a more accurate index, using the 3D printing technology. MATERIALS AND METHODS: We created physical hemithorax models using 3D printing. In this way, we obtained simple radiographs of models for which the lung volume was known accurately. In the first part of the study, we estimated the intraobserver and interobserver agreement as well as the agreement between methods. We created 2 new indices and the results obtained with these; the Light index and the Collins method were compared with data on real lung volume loss using linear regression analysis and by calculating the coefficient of determination (r2). In the second part of the study, we validated the 4 equations, comparing the Light index, the Collins method, and the 2 new indices using regression analysis. For this analysis, we used STATA V14. RESULTS: Both intraobserver and interobserver agreements were very high (<0.9). The agreement between the Collins method and the Light index was poor, with a mean difference of 18.6%. The equation that best represented real lung collapse was the new equation 2. CONCLUSIONS: This study demonstrates the poor agreement between the Light index and Collins method for measuring the extent of lung collapse in pneumothorax and proposes a more accurate equation for this measurement based on a simple chest radiograph.

Creation of a multidisciplinary and multicenter study group for the use of 3D printing in general thoracic surgery: lessons learned in our first year experience.

Introduction: In recent years, the use of 3D printing in medicine has grown exponentially, but the use of 3D technology has not been equally adopted by the different medical specialties. Published 3D printing activity in general thoracic surgery is scarce and has been mostly limited to case reports. The aim of this report was to reflect on the results and lessons learned from a newly created multidisciplinary and multicenter 3D unit of the Spanish Society of Thoracic Surgery (SECT). Methods: This is a pilot study to determine the feasibility and usefulness of printing 3D models for patients with thoracic malignancy or airway complications, based on real data. We designed a point-of-care 3D printing workflow involving thoracic surgeons, radiologists with experience in intrathoracic pathology, and engineers with experience in additive manufacturing. Results: In the first year of operation we generated 26 three-dimensional models out of 27 cases received (96.3%). In 9 cases a virtual model was sufficient for optimal patient handling, while in 17 cases a 3D model was printed. Per pathology, cases were classified as airway stenosis after lung transplantation (7 cases, 25.9%), tracheal pathology (7 cases, 25.9%), chest tumors (6 cases, 22.2%) carcinoid tumors (4 cases, 14.8%), mediastinal tumors (2 cases, 7.4%) and Pancoast tumors (one case, 3.7%). Conclusion: A multidisciplinary 3D laboratory is feasible in a hospital setting, and working as a multicenter group increases the number of cases and diversity of pathologies thus providing further opportunity to study the benefits of the 3D printing technology in general thoracic surgery.

Determinación de grupo de bajo riesgo para tener nódulos metastásicos no detectados por tomografía axial computarizada en la cirugía de las metástasis pulmonares / Determination of a Low Risk Group for Having Metastatic Nodules Not Detected by Computed Tomography Scan in Lung Metastases Surgery

Introducción: En los últimos años existe un debate en relación con la exactitud diagnóstica de la tomografía axial computarizada (TAC) para identificar metástasis pulmonares y la necesidad de la palpación pulmonar para determinar el número de nódulos metastásicos. El objetivo del estudio fue determinar en qué pacientes era más eficaz la TAC para detectar todas las metástasis. Métodos: Se estudiaron todos los pacientes operados de metástasis pulmonar con intención curativa a través de toracotomía entre 1998 y 2012. Todos los casos fueron revisados preoperatoriamente por 2 radiólogos expertos en pulmón. Para el análisis estadístico se utilizó el programa Systat versión 13. Resultados: Ciento ochenta y tres pacientes (63,6% varones) con una edad media de 61,7 años a los que se les realizaron 217 intervenciones. La TAC acertó en 185 casos (85,3%). Discordancias observadas: 26 pacientes (11,9%) con más metástasis resecadas que las observadas y 6 casos (2,8%) con menos metástasis. Agrupando a los pacientes de origen colorrectal con una o 2 metástasis y metástasis única de cualquier origen, la probabilidad de resecar nódulos extras fue del 9,5%. En el resto la probabilidad fue del 27,8%, observándose diferencias estadísticamente significativas (p = 0,001). La edad media de los pacientes en los que no aparecieron nódulos no observados fue de 62,9 años, frente a 56,5 años de media en los pacientes que se escapaba alguna metástasis (p = 0,001). Conclusiones: Se consideró grupo con baja probabilidad de resecar más metástasis que las observadas a los pacientes mayores de 60 años con una o 2 metástasis de origen colorrectal o una de otro origen (AU)

Introduction: In recent years, there has been debate regarding the diagnostic accuracy of computed tomography (CT) in the identification of lung metastases and the need for lung palpation to determine the number of metastatic nodules. The aim of this study was to determine in which patients the CT scan was more effective in detecting all metastases. Methods: We studied all patients who underwent curative thoracotomy for pulmonary metastasis between 1998 and 2012. All cases were reviewed by two expert pulmonary radiologists before surgery. Statistical analyses were performed using Systat version 13. Results: The study included 183 patients (63.6% male) with a mean age of 61.7 years who underwent 217 interventions. The CT scan was correct in 185 cases (85.3%). Discrepancies observed: 26 patients (11.9%) with more metastases resected than observed and 6 cases (2.8%) with fewer metastases. In patients with one or two metastases of colorectal origin or a single metastasis of any other origin, the probability of finding extra nodules was 9.5%. In the remaining patients, the probability was 27.8%, with statistically significant differences (P=0.001). The mean age of the patients in whom no unobserved nodules were detected was 62.9 years compared to 56.5 years on average in patients who were free from any metastases (P=0.001). Conclusions: Patients older than 60 years, with one or two metastases of colorectal origin or a single metastasis from any other origin were considered to be the group with low probability of having more metastases resected than observed (AU)

Determination of a low risk group for having metastatic nodules not detected by computed tomography scan in lung metastases surgery.

INTRODUCTION: In recent years, there has been debate regarding the diagnostic accuracy of computed tomography (CT) in the identification of lung metastases and the need for lung palpation to determine the number of metastatic nodules. The aim of this study was to determine in which patients the CT scan was more effective in detecting all metastases. METHODS: We studied all patients who underwent curative thoracotomy for pulmonary metastasis between 1998 and 2012. All cases were reviewed by two expert pulmonary radiologists before surgery. Statistical analyses were performed using Systat version 13. RESULTS: The study included 183 patients (63.6% male) with a mean age of 61.7 years who underwent 217 interventions. The CT scan was correct in 185 cases (85.3%). Discrepancies observed: 26 patients (11.9%) with more metastases resected than observed and 6 cases (2.8%) with fewer metastases. In patients with one or two metastases of colorectal origin or a single metastasis of any other origin, the probability of finding extra nodules was 9.5%. In the remaining patients, the probability was 27.8%, with statistically significant differences (P=.001). The mean age of the patients in whom no unobserved nodules were detected was 62.9 years compared to 56.5 years on average in patients who were free from any metastases (P=.001). CONCLUSIONS: Patients older than 60 years, with one or two metastases of colorectal origin or a single metastasis from any other origin were considered to be the group with low probability of having more metastases resected than observed.