Patricia Mildred Flach MD, Presenter: Nothing to Disclose

Steffen Ross MD, Abstract Co-Author: Nothing to Disclose

Gary Martin Hatch MD, Abstract Co-Author: Nothing to Disclose

Ulrich Preiss MD, Abstract Co-Author: Nothing to Disclose

Thomas D Ruder, Abstract Co-Author: Nothing to Disclose

Michael J. Thali MD, Abstract Co-Author: Nothing to Disclose

Michael A. Patak MD, Abstract Co-Author: Nothing to Disclose

To retrospectively evaluate the specifity and sensitivity of multi-detector computed tomography (CT), digital radiograph (DR) and low-dose linear slit digital radiography (LSDR, Lodox®) in the detection of incorporated cocaine containers.

Institutional review board approval and governmental permission was obtained. The study population consisted of 50 patients suspected of having incorporated cocaine drug containers (45 males, 5 females, age range 16-45yrs). All underwent radiological imaging: CT n=27, DR n=50, LSDR n=12. A total of 89 exams were performed. Radiological findings were compared with the written record of evidence recovered from the feces of each detained suspect in the hospital-affiliated custody ward. The holding cell is equipped with a guarded drug toilet to collect feces; and to separate it from unwanted debris, leaving only the drug packages. Image analysis was performed prior to knowledge of the gold standard: cocaine packs from feces. Sensitivity and specifity for drug concealment were calculated for each modality.

There were 43 drug mules identified in this study. In the 27 CT exams, 18 were true positive (TP), 8 true negative (TN), 1 false positive (FP) and no false negative (FN). For CT, sensitivity was 100 %, specifity 88 %, positive predictive value (PPV) 95 % and negative predictive value (NPV) 100 %, respectively. In 50 DR exams, 21 were TP, 14 TN, 6 FP and 9 FN showing a sensitivity of 70 %, specifity 93 %, PPV 77 % and NPV 60 %, respectively. LSDR (total number of 12) showed 6 TP, 3 TN, 2 FP and 1 FN with a sensitivity of 85 %, specifity 60 %, PPV/NPV 75 %, respectively. CT showed the highest sensitivity with the highest PPV of 95 % resulting in a NPV of 100 % compared with DR and LSDR.  

The detection of incorporated cocaine drug packs should be performed by CT, rather than by DR or LSDR, in order to provide 100% sensitivity. In the future for radiation protection, low-dose protocols need to be implemented for imaging drug mules while still providing accurate diagnostic outcome.

Drug mules can be reliably identified by CT. Future studies may include evaluation of low dose protocols and identification of incorporated explosives or other hazardous materials.

Flach, P, Ross, S, Hatch, G, Preiss, U, Ruder, T, Thali, M, Patak, M, Sensitivity and Specifity in Identifying Incorporated Cocaine in Drug Mules by Computed Tomography, Plain Radiograph, and Lodox.  Radiological Society of North America 2010 Scientific Assembly and Annual Meeting, November 28 - December 3, 2010 ,Chicago IL. http://archive.rsna.org/2010/9006930.html