Can Microcirculation Changes Predict Non-Healing Ulcers?
Researchers of a recent study say assessing microcirculation changes may help predict whether diabetic foot ulcers will heal. The authors of the study, which was published in a recent issue of The Lancet, utilized medical hyperspectral imaging to perform these assessments and add that the new technology may help identify patients with diabetes who are at higher risk for foot ulcers.
Researchers of the study examined 108 patients, including 51 patients with diabetic neuropathy, 36 with diabetes but no neuropathy and 21 control patients without diabetes. The authors employed the HyperMed Visible MHSI System (HyperMed Inc.), to measure the hemoglobin saturation in patients’ forearms and feet. They also utilized 31P-MRI scans to examine the cellular metabolism of foot muscles by determining and measuring inorganic phosphate and phosphocreatine concentrations.
While the foot was at rest, researchers found hemoglobin saturation was higher in the control and non-neuropathic groups than in the neuropathic patients. The inorganic phosphate/phosphocreatine ratio was higher among patients with diabetes (those with and without neuropathy) than in the control group, according to the study. The study concluded that hemoglobin saturation is lower in the skin of patients with diabetes and the presence of neuropathy exacerbates such an impairment. The foot muscles’ energy reserves are also lower in patients with diabetes and the authors suggest this can be attributed to microcirculation.
John Giurini, DPM, says one day clinicians may use the new technology to predict the healing capacity of diabetic ulcers. The MHSI System examines blood flow and oxygen tension at ulceration margins and he calls this testing more predictable, quantitative and specific than TcPO2 in predicting non-healing ulcerations.
“We believe that tracking skin and metabolism changes will be very helpful in identifying people who fail to heal existing foot ulcers,” adds co-author Aristidis Veves, MD, the Research Director of the Microcirculation Lab at the Joslin-Beth Israel Deaconess Medical Center in Boston. “Tracking skin oxygenation may also be helpful in identifying diabetic patients at risk of developing foot ulcerations.”
What Does The Future Hold?
Although study authors tout the MHSI technology as effective, it is cumbersome and its costs would be prohibitive for day-to-day use in a podiatric setting, according to Dr. Giurini, Chief of the Division of Podiatric Surgery at the Beth Israel Deaconess Medical Center in Boston. However, as studies continue, he notes the goal is to create a practical system that would be easily accessible to all physicians.
Where will future research lead? Drs. Giurini and Veves say they are currently formulating studies that will examine the effect of numerous factors, including exercise and metabolic syndromes, that influence tissue oxygenation and muscle metabolism.
Study Says NPWT Can Reduce Risk Of Second Amputation
By Brian McCurdy, Associate Editor
Patients with diabetes who have undergone partial diabetic foot amputation face a potential for complications, including the risk of a second amputation if the wound does not heal. Can negative pressure wound therapy (NPWT) prevent such complications? A recent landmark study in The Lancet concludes that patients who have undergone NPWT had a higher percentage of healing and a trend toward a reduced risk of undergoing another amputation than those who received standard wound care.
The randomized, multicenter trial involved 162 patients who had undergone partial diabetic foot amputations to the transmetatarsal level. One study group received NPWT (Vacuum Assisted Closure Therapy, KCI) while a control group received standard moist wound care.