Lymphatic filariasis, a parasitic, mosquito-borne disease causes major swelling and deformity of the legs, a condition known as elephantiasis. Around 120 million people worldwide infected with this disease.
Health-care workers rely on leg measurements to assess the severity of the condition. However, measuring legs that are severely swollen, often proves cumbersome and impractical.
Scientists at Washington University School of Medicine in St. Louis have shown a portable scanning device can measure limb enlargement and disfigurement faster and more easily in patients with elephantiasis. The tool makes it easy to obtain accurate measurements and determine whether treatments to reduce swelling are effective.
“This is important because it will allow doctors and researchers to take very accurate limb measurements in developing nations, where there are often limited tools to monitor swollen limbs,” said, senior author Philip J. Budge.
portable scanning device can measure limb
In patients with elephantiasis, the parasitic worms cause the disease to make their way into the lymphatic system and prevent the lymph vessels, which leads to swollen legs. This condition also referred to as lymphedema.
The device essentially an infrared sensor that produces a highly accurate, virtual 3-D reconstruction of the legs using scanning technology.
Researchers test the device on 52 patients with varying stages of lymphedema. The team compared scanner results with other technique results frequently used to ascertain the severity of elephantiasis use of a tape measure, and water displacement.
Tape measures allow researchers to measure limb circumference near the knees, feet and ankles. However, the method difficult to regulate in assessing leg volume because of rough skin surfaces caused by the swelling.
The water displacement procedure requires patients submerging a leg in a water tank and then measuring how much water displaces. Budge said, this is the gold standard for measuring limb volume, but it is awkward and impractical to use in field studies.
The study showed that the infrared scanner provided measurements of leg volume and of limb circumference at multiple points that accurate and precise as those obtained by the tape measure and water displacement.
Researchers found that the average time required for scanner measurements of both legs is 2.2 minutes. In comparison, the tape measure and water displacement methods took an average of 7.5 minutes and 17.4 minutes.
The scanning tool also offers convenience. Many patients with swollen limbs are difficult to travel from their homes to the clinic to have their measurements taken.
Researchers said, this is the first time that infrared 3-D scanning technology used in patients with filarial lymphedema.
More information: [AJTMH]