Keywords:
Image Quality, Cardiac, Forensic / Necropsy studies, Radiographers, CT, Comparative studies, Observer performance, Technical aspects, Forensics, Image verification, Outcomes, Prospective, Experimental, Performed at one institution
Authors:
D. Riegler; Vienna/AT
DOI:
10.26044/ecr2020/C-08294
Methods and materials
Patient population:
In this study five cases were included, advanced decomposition, torso injuries and excessive obesity had been exclusion criteria. The mean age of the studied group was 68.2 (±14.6) years, the mean weight was 63.6 (±19.4) kg and the mean body height was 173.2 (±9.5) cm. There were 3 male and 2 females human cadavers.
Data acquisition:
The radiological examination was carried out before autopsy on a 16-slice CT scanner. Based on the institute standard, four alternative protocols were created, which deviated from each other in the scan parameters kVp, mAs, slice thickness and increment (Table 1). Each body was scanned natively in the cardiac region using these five protocols ( Fig. 1 ).
Scan range was from middle of larynx to phrenicocosteal sinus. Each corpse was stored on its back on the examination table with its head in the integrated head shell of the table. The arms were tied together using medical tape and were positioned over the head.
Data analysis:
The native heart protocols were evaluated using a 5-point ordinal-LIKERT-scale (1:very good; 2:good; 3:acceptable; 4:poor; 5:very poor). Image quality assessment was performed by four radiologists according to eight criteria. The raters assessed the image data independently without knowledge of the institute standard. Five criteria related to the anatomy of the heart, one criterion to calcifications and one criterion to the subjective image noise. The final criterion related to the overall appearance of the respective protocol.
Finally, the inter-rater reliability (IRR) was calculated using Kendall´s coefficient of concordance in order to assess the agreement between the raters (Table 2). P-value of less than 0,05 was considered to indicate statistically significance.