LDCT, the Radiologist, and Drug Smuggling Detection

Whitney J. Palmer

Radiologist can a fundamental role to play in detecting illicit drug smuggling, and knowing what to look for matters.

Low-dose CT (LDCT) is effective for more than diagnosing acute conditions or providing follow-up – it can also be integral in detecting illicit drug smuggling.

Although X-ray imaging has been most commonly used to pinpoint drug smuggling – either via body packing (planned drug swallowing) or body stuffing (unplanned drug swallowing) – it has been abandoned due to low negative predictive value. LDCT has taken its place as the most effective detection method, and, in a May 18 article published in Clinical Imaging, a team of investigators from France explained the vital role the radiologist plays in these situations.

“Low dose abdominal CT is now essential for the diagnosis of ‘in corpore’ illicit drug transportation. Radiologists have a fundamental role in the medico-legal process of drug smuggling diagnosis,” said the team led by Julien Puntonet, from the radiology department at Hotel Dieu Hospital, Assistance Publique-Hopitaux de Paris. “The radiologist must be aware of the imaging characteristics of ‘in corpore’ illicit drug transportation and [must] know the situations that could change the treatment or the follow-up of the patient.”

Effective imaging requires a strategy for the best image capture, a knowledge of how drugs appear in scans, and a concise reporting method, they said.

To limit the opportunities for intentional movement by the patient that can degrade images, limit scans to two-to-three acquisitions, the team suggested. Use a tube current of 125 mA instead of 100 mA because it allows for better detection of drug packets, and acquire slices that are at least 1.5-mm thick as they improve the ability to visualize drug pellets that are at least 1 cm in size.

The various types of drugs typically smuggled do have different characteristics on imaging, but LDCT alone cannot reliably distinguish between drug types. However, experimental evidence indicates that adding dual-energy CT to the mix can assist with differentiation.

CT Presentation of Drug Types

Substance

Mean Attenuation Value (Hounsfield units)

Pure Heroin

-520 HU

Pure cocaine

-219 HU

Pure Hasish

+700 HU

Pure Methamphetamine

-100 to +150 HU

Cocaine with Crack or Cocaine Powder

Up to +300 HU

Frequently, it is more important for radiologists to be able to determine whether the drug packets have ruptured, the team said.

“The radiologist must be aware that drug smugglers are very creative,” the team explained, “and new packaging techniques may combine plastic film, aluminum foil, and other medium.”

Whether a package breaks, knowing what to look for can be critical for the patient’s care. For example, on CT, a broken package of solid crack cocaine will appear as a squared hyperattenuating structure that is typically located in the gastric lumen. In addition, a liquid cocaine-filled balloon will appear as random-shaped hyperattenuating packets that are molded to the bowel lumen with well-defined borders.

In addition to acute drug toxicity, the team said radiologists should also be alert for any gastrointestinal obstructions or perforations that would immediately send a patient for surgery.

In the structured report, be sure to describe the number of packets visualized – if there are more than 20, indicate a potential range. In addition, detail the exact location (stomach, jejunum, ileum, colon, or rectum) because it can affect treatment and follow-up. Also include any incidental findings.

“The radiologist has a social and medico-legal role in the management of drug smuggling,” the team said. “[Their] role is not restricted to the detection of packets, but should also include the identification of potential complications, especially when the body packer is a minor person or a pregnant woman.”

The team did note, though, that while CT does have near 100-percent sensitivity in detecting drug smuggling in body packers, false negative are possible. In some instances, the illicit substance might be ingested diamonds or dollar bills. In other cases, the visualized content could be bone that appears hyperattenuating to the bowel lumen.

For examples of how drug packets appear on CT images, review the study.