Evaluation of operative characteristics of High Resolution Chest CT: experience at the Hospital Universitario San Ignacio

Evaluación de las características operativas de la escanografía de tórax de alta resolución: experiencia en el Hospital Universitario San Ignacio

Introduction: with regard to the clinical value of high-resolution chest scanning, it has been considered that some studies can offer very fine radiologic descriptions that often lead to additional invasive diagnostic interventions that in the end do not confirm the initial diagnostic suspicion, nor assign meaning to the described radiologic findings.

Objectives: the purpose of this study is to assess the operational characteristics of chest scanning compared to a combined gold standard (biopsies, microbiologic studies, and clinical follow-up), in order to assess its diagnostic yield. It also intends to assess the need for high-resolution chest scanning in the diagnostic workup of the patient with pulmonary disease, thus assessing the percentage of additional invasive interventions that were carried out with regard to the findings of the chest scan, and that eventually had nondiagnostic results.

Materials and Methods: a retrospective study was carried out by reviewing the clinical records of 250 patients who underwent high-resolution chest scanning at San Ignacio University Hospital in Bogota, Colombia, between April 2008 and April 2010. The presumptive diagnosis suggested by the images and the description of semiological findings were compared with a combined gold standard; once the final diagnosis was established by the combined gold standard, the patients were classified into etiological categories.

Results: of 250 reviewed cases, it was found that 44,8% of the patients had infectious diseases, 19,6% had neoplastic diseases, 17,12% had interstitial diseases, 9,2% had other pulmonary diseases, 4% had undetermined findings, 3,2% had simultaneous infectious and interstitial disease, and 2% were normal. The sensitivity of high-resolution chest scanning for diagnosing pulmonary disease in the general population of the study was 83,3%, and its specificity was 90,9%. Positive predictive value was 99,5%, and negative predictive value was 94.09%.

Conclusions: high-resolution chest scanning is a useful tool for the workup of the patient with lung disease. It is highly capable of detecting pulmonary injuries, proposing differential diagnoses, and orienting the most adequate site for biopsy. It is important to interpret the study with clinical information that permits successful diagnostic workup.