Reliability of smartphone‐based radiographic interpretation for evaluating cardiogenic pulmonary oedema in dogs

Abstract

Objective To compare the accuracy of radiological diagnosis of cardiogenic pulmonary oedema in dogs using two viewing platforms. Material and Methods A retrospective cross‐sectional study including cases admitted between January 2012 and December 2016. Thoracic radiographs from 121 dogs with and without cardiogenic pulmonary oedema were included. The study was divided into two phases, and images were interpreted by two observers: a radiologist (R1) and a cardiologist (R2). In the first phase, images were sent in JPEG format for interpretation using a smartphone. In the second phase, DICOM images were interpreted at the standard workstation using a DICOM viewer. Receiver operating characteristic curves were generated to evaluate the accuracy of each method of radiological evaluation, and Spearman correlation was used to evaluate the correlation between the evaluations performed by R1 and R2. Results The accuracy of R1 in diagnosing pulmonary oedema was 94.1% (95% confidence interval: 88.3 to 97.5) for DICOM images and 90.7% (95% confidence interval: 84.1 to 95.1) for JPEG/smartphone. The accuracy of R2 was 89.5% (95% confidence interval: 82.6 to 94.4) for DICOM images and 90.6% (95% confidence interval: 83.9 to 95.2) for JPEG/smartphone. There was no statistically significant difference between these evaluation methods. The correlation coefficient for R1 and R2 was 0.815 and 0.761, respectively. Clinical Significance Cardiogenic pulmonary oedema may be reliably diagnosed on thoracic radiographs viewed on a smartphone by a specialist, which may expedite treatment.

Right lung agenesis in a one‐year‐old Chihuahua

“…Thus, it was not possible to establish whether this blackened appearance was due to true overexposure, clipping at the preprocessing stage or an incorrect diagnostic specifier selection. A recent study to evaluate for the specific question of presence of cardiogenic oedema found no statistical difference in the evaluation of images in DICOM and JPEF format 16. However, as a JPEG file can only store 9–12 bit pixel scales compared with the 16‐bit supported by the DICOM format, some loss of greyscale during the compression process is conceivable 17…”

“…A recent study to evaluate for the specific question of presence of cardiogenic oedema found no statistical difference in the evaluation of images in DICOM and JPEF format. 16 However, as a JPEG file can only store 9-12 bit pixel scales compared with the 16-bit supported by the DICOM format, some loss of greyscale during the compression process is conceivable. 17 The postprocessing alteration of grey scale in digital radiography is commonly referred to as 'windowing', whereby altering the window width alters the contrast and altering the window level alters the brightness.…”