Low-dose computed tomography to detect body-packing in an animal model

Using CT scout view to scan illicit drug carriers may reduce radiation exposure

OBJECTIVE

The aim of this study was to present our experience on the evaluation of suspected illicit drug carriers via computerized tomography scout view (CTSV) with analysis of detectability and features such as content, form and density.

METHODS

A total of 120 individuals suspected of body packing were screened via CT in a university emergency department between January 2014 and December 2017.

RESULTS

88.3% of 120 body packing cases examined in the study were male. The median (1st quartile-3rd quartile) age of the cases was 35.5 (30-41) years. We found that solid packs have a 4.573-fold higher likelihood of detection in CTSV screening than liquid ones (95%CI: 1.879-11.134). Additionally, the number of CT scans needed were significantly associated with capsule localization (stomach) (OR:7.178, 95%CI: 2.420-21.293) and solid form packs (OR: 8.705, 95%CI: 2.318-32.692) are associated with number of CT scans.

CONCLUSION

CTSVs have a successful detection rate, especially in solid form packs. Our results suggest that conclusive CTSV imaging for body packing may be recommended to delay the application of the next CT scan until the passage of the first capsule; thereby preventing unnecessary radiation exposure.

Body packing, body stuffing and body pushing: Characteristics and pitfalls on low-dose CT

Because of availability and low radiation dose level, low dose computed tomography (CT) is now commonly used to identify illicit in corpore drug transportation. This review illustrates the most common CT findings of in corpore drug transportation and describes complications due to in corpore drug transportation, with a special emphasis on low dose CT. Major information such as number of packets, exact location and aspect of packets must be assessed. Radiologist must be aware of the imaging characteristics of "in corpore" illicit drug transportation, and should know situations that may alter drug smugglers management.

The usefulness of non-contrast abdominal computed tomography for detection of residual drugs in the stomach of patients with acute drug overdose

Objectives: If clinicians can know that there are many life-threatening drugs left in the stomach through a non-invasive method over 60 min after drugs ingestion, it may be preferable to minimize absorption of remnant drugs through various methods according to the characteristic of the drug. Computed tomography (CT) has gained wide acceptance in the detection of drug mules. Therefore, we evaluated the prevalence of drugs in the gastric lumen using abdominal non-contrast CT, performed over 60 min after acute drug poisoning. Materials and methods: This was a prospective cohort study of patients with acute drug poisoning who were admitted to the emergency department (ED) between March 2017 and February 2018. If the patient visited the ED over 60 min after ingestion of life-threatening or unknown drugs, non-contrast CT scan was performed. "Presence of drugs" was defined in the non-contrast CT as a round-shaped lesion with higher density than the gastric mucosa. In addition, "positive radiodense image" was defined as that with higher density than the gastric mucosa regardless of drug appearance in the non-contrast CT scan. Results: Among a total of 482 patients with drug poisoning, 140 were finally included in the study. Residual drugs were detected in 36 patients (25.7%). Further, regardless of the presence of drugs, 58 patients (41.4%) showed positive radiodense image in the stomach. The median Hounsfield unit of drugs was 131.5 and that of food materials in the stomach was 34.5. Total duration of hospital stay was significantly longer in the "absence of drug" group and sustained-release drugs were detected more frequently in the "presence of drugs" group. Conclusions: Detection rate of drugs and presence of positive radiodense image, regardless of drug appearance, were as high as 25.7% and 41.4%, respectively. Sustained-release drugs were detected more frequently in the "presence of drugs" group.

Noise insertion in CT for cocaine body packing: where is the limit of extensive dose reduction?

Background

To evaluate the detection rate and image quality in CT-body-packer-screening at different radiation-dose levels and to determine a dose threshold that enables a reliable detection of incorporated body packs and incidental findings with a maximum of dose saving.

Materials and methods

We retrospectively included 27 individuals who underwent an abdominal CT with automated exposure control due to suspected body packing. CT images were reconstructed at different radiation-dose levels of 50%, 10, 5% and 1% using iterative reconstructions. All 135 CT reconstructions were evaluated by three independent readers. Reviewers determined the presence of foreign bodies and evaluated the image quality using a 5-point ranking scale. In addition, visualization of incidental findings was assessed.

Results

A threshold of 5% (effective dose 0.11 ± 0.07 mSv) was necessary to correctly identify all 27 patients with suspected body packing. Extensive noise insertion to a dose level of 1% (0.02 ± 0.01 mSV) led to false-positive solid cocaine findings in three patients. Image quality was comparable between 100 and 50%. The threshold for correct identification of incidental findings was 10% of the initial dose (effective dose 0.21 ± 0.13 mSv).

Conclusions

Our results indicate that dose of abdominal CT for the detection of intracorporeal cocaine body packets can be markedly reduced to up to 5% of the initial dose while still providing sufficient image quality to detect ingested body packets. However, a minimum effective dose of 0.21 mSv (10% of initial dose) seems to be required to properly identify incidental findings.

Comparison of low dose and standard dose abdominal CT scan in body stuffers

PURPOSE

Detection of body stuffers is challenging in emergency departments. Because of the small size of baggies, plain radiograph is of little value in most suspects. On the other hand, abdomen CT scan is burdened by high cost and radiation dose. This study was performed to compare the image quality, radiation dose and accuracy of low-dose CT scan in comparison with standard dose.

MATERIAL AND METHODS

In this prospective study, suspected body stuffers who were referred to the radiology department underwent two different protocols of abdominal non-contrast CT scan simultaneously: low-dose (with equivalent dose to conventional abdominal x-ray) and standard dose. Standard dose CT scan was considered as the reference. Low-dose CT scans were evaluated for detection of baggies by two radiologists blinded to the result of standard dose CT. Image quality, noise, dose-length product (DLP) and effective dose (ED) compared between two groups.

RESULTS

The study consisted of 40 patients (33.38 ± 7.4 years). Standard dose CT evaluation was positive in 22 patients (55%). In comparison with standard dose CT scan, low-dose group had a sensitivity of 86%, specificity of 100%, PPV and NPV of 100% and 86%. The accuracy of low-dose CT scan for detection of baggies larger than 1 cm was 100%. However, from the 3 cases that could not be detected with low dose protocol, one had CT features suspected for baggies rupture which was intubated and later deceased. Noise average of low-dose protocol, was approximately 7 times greater than standard dose group, while DLP and ED were 9.7 times less.

CONCLUSION

Low dose CT scan appears to be an appropriate screening method for body stuffers, especially when the baggies are larger than one centimeter. However, in the presence of severe clinical symptoms, a standard dose CT scan will be more helpful due to better image quality especially in suspected ruptured baggies.

Systematic Evaluation of Radiation Dose Reduction in CT Studies of Body Packers: Accuracy Down to Submillisievert Levels

OBJECTIVE

The objective of this study was to systematically evaluate the accuracy of abdominal CT performed at different radiation dose levels for the detection of body packs in human cadavers, in comparison with the accuracy of abdominal radiography.

MATERIALS AND METHODS

In this study, differing numbers of body packs (range, 0-20) were placed in the alimentary tract of human cadavers and then underwent imaging with abdominal radiography and with CT performed at different radiation dose levels (ranging from the standard abdominal CT dose to the technical minimum dose). Depiction of body packs on abdominal radiographs and on each CT scan was assessed by two independent blinded radiologists, and the accuracy of detection of body packs was calculated. The radiation dose associated with abdominal radiography was measured, and the effective radiation dose associated with CT was estimated.

RESULTS

The mean (± SD) effective radiation dose for abdominal radiography was 1.4 ± 0.3 mSv, whereas the mean effective dose of CT ranged from 0.1 to 9.6 mSv. Interobserver agreement for body pack detection was moderate (κ = 0.51) for abdominal radiography and good (κ = 0.72-0.85) for CT. In a per-body pack analysis, abdominal radiography depicted 42% of the body packs with a sensitivity of 71% and a specificity of 100%. When performed at radiation dose levels of 0.6 mSv or greater, CT correctly detected all body packs. In per-person analysis, the sensitivity and specificity of CT for the correct detection of at least one body pack per cadaver was 100% for all radiation dose levels.

CONCLUSION

CT performed at a dose of 0.6 mSv can be used for the detection of body packs. With a sensitivity and specificity of 100%, CT is superior to abdominal radiography in terms of reliability, associated radiation dose, and accuracy of detection.

Added value of lung window in detecting drug mules on non-contrast abdominal computed tomography

We evaluated the added value of lung window in non-contrast computed tomography (CT) of suspected body packers or stuffers. Forty suspected drug mules who were referred to our tertiary toxicology center were included. The final diagnosis of drug mule was based on the detection of packs in stool examination or surgery. Non-contrast CT scans were retrospectively interpreted by two blinded radiologists in consensus before and after reviewing the lung window images. The diagnostic performance of abdominal window scans alone and scans in both abdominal and lung windows were subsequently compared. Seven body packers and 21 body stuffers were identified. The sensitivity, negative predictive value (NPV), and diagnostic accuracy of scans in detection of drug mules (either drug packers or stuffers) raised from 60.7, 52.1, and 72.5 to 64.2, 54.5, and 75.0 %, respectively, with a more number of packs being detected (114 vs. 105 packs). In the body packers group, the diagnostic performance of both abdominal windows scans and combined abdominal and lung windows scans were 100 %. In the body stuffers group, the sensitivity, NPV, and diagnostic accuracy of scans increased from 47.6, 52.1, and 55.0 to 52.3, 54.5, and 57.5 %, respectively, after the addition of lung windows. Reviewing the lung window on non-contrast abdominal CT can be helpful in detection of drug mules.

The role of radiology in diagnosis and management of drug mules: an update with new challenges and new diagnostic tools

Emergency physicians and radiologists have been increasingly encountering internal concealment of illegal drugs. The packages commonly contain powdered solid drugs such as cocaine, heroin, methamphetamine and hashish, but they may also contain cocaine in the liquid form. The second type of package has recently been more commonly encountered, and poses a greater diagnostic challenge. As clinical evaluation and laboratory tests frequently fail to make the correct diagnosis, imaging examination is typically required. Imaging methods assume a vital role in the diagnosis, follow-up and management. Abdominal X-ray, ultrasonography, CT and MRI are used for the imaging purposes. Among the aforementioned methods, low-dose CT is state-of-the-art in these cases. It is of paramount importance that radiologists have a full knowledge of the imaging characteristics of these packages and accurately guide physicians and security officials.

Imaging of drug smuggling by body packing

Body packing, pushing, and stuffing are hazardous practices with complex medicolegal and social implications. A radiologist plays both a social and a medicolegal role in their assessment, and it should not be limited only to the identification of the packages but must also provide accurate information about their number and their exact location so as to prevent any package remains in the body packer. Radiologists must also be able to recognize the complications associated with these risky practices. Imaging assessment of body packing is performed essentially through plain abdominal X-ray and computed tomography scans. Ultrasound and magnetic resonance imaging, although with some advantages, actually have a limited use.

Radiographic features of intracorporeally smuggled liquid cocaine

PURPOSE

The radiological features of intracorporeally smuggled cocaine powder are well-established. Liquid cocaine is a novel method for intracorporeal drug smuggling. We describe radiological features of liquid cocaine on abdominal plain films and computerized tomographic (CT) scans and compare them to those of cocaine powder.

METHODS

Twenty-five suspected cocaine smugglers (13 males, 12 females, average age 38 years) underwent abdominal plain film radiography for drug detection between 2010 and 2014. Ten of them also underwent a CT scan. Eight were found to be smuggling cocaine powder and 17 were found to be smuggling liquid cocaine. We identified two new imaging characteristics unique to intracorporeal liquid cocaine on both plain films and CT scans, and compared them to the radiological features of cocaine powder.

RESULTS

The radiological features of intraabdominal liquid cocaine packets on plain abdominal films (n = 17) were similar in opacity to bowel content and had an irregular shape that conformed to the intestinal contour. We identified what we termed "thin lucent lines" that were created by gas trapped between the packets. Four CT scans revealed that liquid cocaine was hyperdense compared to bowel content, that the packets had irregular shapes, and that the gas trapped between the packets formed a "jigsaw" pattern, a heretofore non-described finding that was present in all four scans.

CONCLUSIONS

Liquid cocaine has several unique imaging features that assist its detection on abdominal plain film. A CT scan can assist detection in inconclusive cases by demonstrating hyperdense irregular packets of liquid cocaine and a "jigsaw" pattern of gas between them.

Sensitivity and specificity of CT scanning for determining the number of internally concealed packages in 'body-packers'

INTRODUCTION

If package counts on abdominal CTs of body-packers were known to be accurate, follow-up CTs could be avoided. The objective was to determine the accuracy of CT for the number of concealed packages in body-packers, and the reliability of package counts reported by body-packers who admit to concealing drugs.

METHODS

Suspected body-packers were identified from the emergency departments (ED) database. The medical record and radiology reports were reviewed for package counts determined by CT, patient-reported and physically retrieved. The last method was used as the reference standard. Sensitivity, specificity, positive predictive values (PPV) and negative predictive values (NPV) were calculated for CT package count accuracy. Reliability of patient-reported package counts was assessed using Pearson's correlation coefficient.

RESULTS

There were 50 confirmed body-packers on whom 104 CT scans were performed. Data for the index and reference tests were available for 84 scans. The sensitivity, specificity, PPV and NPV for CT package count were 63% (95% CI 46% to 77%), 82% (95% CI 67% to 92%), 76% (95% CI 58% to 89%) and 71% (95% CI 56% to 83%) respectively. For CTs with a package count<15, the sensitivity, specificity, PPV and NPV for CT package count were 96% (95% CI 80% to 99%), 95% (95% CI 82% to 99%), 93% (95% CI 76% to 99%) and 97% (95% CI 86% to 100%), respectively. Correlation between patient-reported package counts and the number of packages retrieved was high (r=0.90, p<0.001, R2=81%).

CONCLUSIONS

The accuracy of CT for determining the number of concealed packages is poor, although when applied to patients with few concealed packages accuracy is high and is useful as a rule-out test. Among patients who have admitted to drug concealment, the number of packages reported to be concealed is reliable.

Walking on thin ice! Identifying methamphetamine "drug mules" on digital plain radiography

OBJECTIVE

The purpose of this study was to retrospectively evaluate the sensitivity, specificity and accuracy of identifying methamphetamine (MA) internal payloads in "drug mules" by plain abdominal digital radiography (DR).

METHODS

The study consisted of 35 individuals suspected of internal MA drug containers. A total of 59 supine digital radiographs were collected. An overall calculation regarding the diagnostic accuracy for all "drug mules" and a specific evaluation concerning the radiological appearance of drug packs as well as the rate of clearance and complications in correlation with the reader's experience were performed. The gold standard was the presence of secured drug packs in the faeces.

RESULTS

There were 16 true-positive "drug mules" identified. DR of all drug carriers for Group 1 (forensic imaging experienced readers, n = 2) exhibited a sensitivity of 100%, a mean specificity of 76.3%, positive predictive value (PPV) of 78.5%, negative predictive value (NPV) of 100% and a mean accuracy 87.2%. Group 2 (inexperienced readers, n = 3) showed a lower sensitivity (93.7%), a mean specificity of 86%, a PPV of 86.5%, an NPV of 94.1% and a mean accuracy of 89.5%. The interrater agreement within Group 1 was 0.72 and within Group 2 averaged to 0.79, indicating a fair to very good agreement.

CONCLUSION

DR is a valuable screening tool in cases of MA body packers with huge internal payloads being associated with a high diagnostic insecurity. Diagnostic insecurity on plain films may be overcome by low-dose CT as a cross-sectional imaging modality and addressed by improved radiological education in reporting drug carriers on imaging.

ADVANCES IN KNOWLEDGE

Diagnostic signs (double-condom and halo signs) on digital plain radiography are specific in MA "drug mules", although DR is associated with high diagnostic insecurity and underreports the total internal payload.

Radiological and practical aspects of body packing

Body packing represents the concealment of illegal substances in a person's body with the aim of smuggling. "Body packers" either swallow drug-filled packets or introduce drug-filled packets into their bodies rectally or vaginally with the purpose of concealing them. The three main smuggled drugs are cocaine, heroin and cannabis products. Body packing represents a serious risk of acute narcotic toxicity from drug exposure, intestinal obstruction owing to pellet impaction and bowel perforation with consequent abdominal sepsis. A suspected body packer is generally admitted to hospital to perform imaging investigations and confirm the presence of drugs in his/her body. Radiological imaging methods are essential to diagnose body packing and to detect potential complications. Increasing sophistication of traffickers and improvements in packaging add to the detection difficulty. Radiologists should be aware of the appearance of drug packets in a range of imaging modalities. This article informs physicians about the challenging aspects of body packing, its background and medicolegal issues, what imaging methods can be used and what criteria are necessary to perform a correct diagnosis.

Low-dose CT in body-packers: delineation of body packs and radiation dose in a porcine model

PURPOSE

To compare low-dose computed tomography (CT) with standard CT and conventional radiography (CR) regarding delineation of body packs and radiation dose.

METHODS

Nine samples of illicit drugs including cocaine, heroin, and hashish were positioned in the rectum of a 121.5 kg pig cadaver. Each sample was scanned on a 64-row MDCT with 120 kV: one standard modulated pelvic protocol (STD), and without modulation at 80 mA (LD80), 30 mA (LD30), and 10 mA (LD10). Additionally, conventional abdominal anterior-posterior radiographs (77 kV and 106 ± 13 mA) were taken. Body pack characteristics (wrapping, content, shape) were rated independently by two radiologists and summarized to a delineation score from 0 to 9 with scores ≥6 representing sufficient delineation. Mean delineation scores were calculated for CR and CT protocols. These were additionally differentiated for readings in soft tissue (S), lung (L), user defined, variable window settings (V), and in cumulative window evaluation including all the other window settings (SLV). Effective doses were calculated (mSv).

RESULTS

The CR delineation score was insufficient (3.1 ± 2.5; 2.4 ± 0.3 mSv). For CT, the SLV window setting performed best (p < 0.01). Its score significantly (p < 0.01) declined with decreasing effective radiation doses: STD (8.8 ± 0.5; 10.6 mSv), LD80 (8.2 ± 0.7; 2.6 mSv), LD30 (6.8 ± 1.3; 1.0 mSv), and LD10 (4.6 ± 1.9; 0.3 mSv). Thus, LD30 was the protocol using the lowest but sufficient dose. Moreover, for LD30 further differentiation between the particular window settings resulted in scores of 6.4 ± 1.3 (L), 6.3 ± 1.2 (V), and 3.1 ± 1.0 (S).

CONCLUSIONS

With appropriate window settings, low-dose CT at 30 mA allowed for sufficient body-pack delineation below the dose of CR, which itself performed insufficient.

Detection of residual packets in cocaine body packers: low accuracy of abdominal radiography-a prospective study

OBJECTIVE

To evaluate the accuracy of abdominal radiography (AXR) for the detection of residual cocaine packets by comparison with computed tomography (CT).

METHODS

Over a 1-year period unenhanced CT was systematically performed in addition to AXR for pre-discharge evaluation of cocaine body packers. AXR and CT were interpreted independently by two radiologists blinded to clinical outcome. Patient and packet characteristics were compared between the groups with residual portage and complete decontamination.

RESULTS

Among 138 body packers studied, 14 (10 %) had one residual packet identified on pre-discharge CT. On AXR, at least one reader failed to detect the residual packet in 10 (70 %) of these 14 body packers. The sensitivity and specificity of AXR were 28.6 % (95 % CI: 8.4-58.1) and 100.0 % (95 % CI: 97.0-100.0) for reader 1 and 35.7 % (95 % CI: 12.8-64.9) and 97.6 % (95 % CI: 93.1-99.5) for reader 2. There were no significant patient or packet characteristics predictive of residual portage or AXR false negativity. All positive CT results were confirmed by delayed expulsion or surgical findings, while negative results were confirmed by further surveillance.

CONCLUSION

Given the poor performance of AXR, CT should be systematically performed to ensure safe hospital discharge of cocaine body packers.

KEY POINTS

• Both abdominal radiography and computed tomography can identify gastrointestinal cocaine packets. • Ten per cent of body packers had residual packets despite two packet-free stools. • Seventy per cent of these residual packets were missed on AXR. • No patient or packet characteristics predicted residual packets or AXR false negativity. • CT is necessary to ensure safe medical discharge of body packers.

Comparison of diagnostic value of multidetector computed tomography and X-ray in the detection of body packing

OBJECTIVE

Radiologists and other clinicians are facing an increasing number of illegal drug-related medical conditions. We aimed to draw attention to this growing global problem and to highlight some of the important points related to diagnosis and follow-up of body packing. We compare the diagnostic performance of unenhanced multidetector CT (MDCT) and abdomen X-ray for the detection of drug-filled packets.

MATERIALS AND METHODS

Sixty-seven suspects, who underwent both CT and X-ray examinations, have been included in the study. All MDCT and X-ray images were independently and retrospectively reviewed by two observers with different degrees of experience in abdomen imaging. Fifty-two of them were identified as body packers finally. Interobserver agreement, sensitivity, specificity, positive and negative predictive value were calculated.

RESULTS

Two types of packets with different characteristics were identified in all body packers. Type 1 packets (solid-state drug) were found in 41 patients and type 2 packets (liquid cocaine) in 11 patients. All statistical analyses concern the detection of any packets. That is, the whole evaluation has been performed per patient. Sensitivity/specificity values of type 1 and type 2 packets for MDCT were 100-98%/100-100% and 100-100%/100-100%, respectively. Besides, sensitivity/specificity values of type 1 and type 2 packets for X-ray were 93-90%/100-91% and 64-45%/73-71%, respectively. In addition, interobserver agreements for detection of any packets were excellent (κ=0.96) and good (κ=0.75) for interpretation of MDCT and X-ray, respectively.

CONCLUSION

Unenhanced MDCT is a fast, accurate and easily used diagnostic tool with high sensitivity and specificity for the exact diagnosis of body packing.

"Drug mules" as a radiological challenge: sensitivity and specificity in identifying internal cocaine in body packers, body pushers and body stuffers by computed tomography, plain radiography and Lodox

PURPOSE

The purpose of our study was to retrospectively evaluate the specificity, sensitivity and accuracy of computed tomography (CT), digital radiography (DR) and low-dose linear slit digital radiography (LSDR, Lodox(®)) in the detection of internal cocaine containers.

METHODS

Institutional review board approval was obtained. The study collectively consisted of 83 patients (76 males, 7 females, 16-45 years) suspected of having incorporated cocaine drug containers. All underwent radiological imaging; a total of 135 exams were performed: nCT=35, nDR=70, nLSDR=30. An overall calculation of all "drug mules" and a specific evaluation of body packers, pushers and stuffers were performed. The gold standard was stool examination in a dedicated holding cell equipped with a drug toilet.

RESULTS

There were 54 drug mules identified in this study. CT of all drug carriers showed the highest diagnostic accuracy 97.1%, sensitivity 100% and specificity 94.1%. DR in all cases was 71.4% accurate, 58.3% sensitive and 85.3% specific. LSDR of all patients with internal cocaine was 60% accurate, 57.9% sensitive and 63.4% specific.

CONCLUSIONS

CT was the most accurate test studied. Therefore, the detection of internal cocaine drug packs should be performed by CT, rather than by conventional X-ray, in order to apply the most sensitive exam in the medico-legal investigation of suspected drug carriers. Nevertheless, the higher radiation applied by CT than by DR or LSDR needs to be considered. Future studies should include evaluation of low dose CT protocols in order to address germane issues and to reduce dosage.

Feasibility of abdominal plain film images in evaluation suspected drug smuggler

OBJECTIVE

Drug smuggling in the gastrointestinal tract has soared within the last 20 years. Though illegal substances in the gastrointestinal tract can be visualized with ultrasound, MRI and CT, the abdominal radiograph has by far remained the most frequently used way of detecting smuggled drugs. The purpose of the study was to evaluate the inter-radiologist interpretation error and the reliability of the abdominal radiograph in detecting smuggled drugs.

MATERIALS AND METHODS

A total of 279 abdominal radiographs of suspected smugglers were classified by three radiologists as clearly positive or negative for drug smuggling. All available information about the cases was collected from the customs officers and police.

RESULTS

Out of these cases 203 (73%) were interpreted as negative and 35 (13%) as positive by all three radiologists. In 86% of the cases there was, therefore, an inter-radiological agreement in interpreting the images. In 41 (14%) cases, however, there was an inter-radiologist disagreement. Kappa-value for inter-observer variability was 0.70.

CONCLUSIONS

In up to a seventh of the abdominal radiographs the interpretation can be challenging even for an experienced radiologist. False positive interpretation can lead to innocent passengers being detained in vain. As negatively interpreted images usually result in releasing of the suspect, there is no way of knowing how many false negative occur. This makes the abdominal radiograph a suboptimal examination, and low dose CT should be considered as the screening modality for gastrointestinal drug smugglers.