Wound Area Measurement with Digital Planimetry: Improved Accuracy and Precision with Calibration Based on 2 Rulers.

INTRODUCTION: In the treatment of chronic wounds the wound surface area change over time is useful parameter in assessment of the applied therapy plan. The more precise the method of wound area measurement the earlier may be identified and changed inappropriate treatment plan. Digital planimetry may be used in wound area measurement and therapy assessment when it is properly used, but the common problem is the camera lens orientation during the taking of a picture. The camera lens axis should be perpendicular to the wound plane, and if it is not, the measured area differ from the true area. RESULTS: Current study shows that the use of 2 rulers placed in parallel below and above the wound for the calibration increases on average 3.8 times the precision of area measurement in comparison to the measurement with one ruler used for calibration. The proposed procedure of calibration increases also 4 times accuracy of area measurement. It was also showed that wound area range and camera type do not influence the precision of area measurement with digital planimetry based on two ruler calibration, however the measurements based on smartphone camera were significantly less accurate than these based on D-SLR or compact cameras. Area measurement on flat surface was more precise with the digital planimetry with 2 rulers than performed with the Visitrak device, the Silhouette Mobile device or the AreaMe software-based method. CONCLUSION: The calibration in digital planimetry with using 2 rulers remarkably increases precision and accuracy of measurement and therefore should be recommended instead of calibration based on single ruler.

Area of the diabetic ulcers estimated applying a foot scanner-based home telecare system and three reference methods.

BACKGROUND: Diabetic foot ulcer area is a basic parameter used for monitoring the wound healing and effectiveness of the treatment applied. TeleDiaFoS (developed earlier in collaboration with the Department and Clinic of Gastroenterology and Metabolic Diseases, Medical University of Warsaw, Warsaw, Poland) is one of just a few systems available that make possible monitoring of the wound size remotely based on the foot scans transmitted to the physician from a patient's home. The aim of this study was to compare the diabetic foot ulcer areas measured using TeleDiaFoS with the results obtained using three reference methods. METHODS: The reference measurements were conducted using the elliptical method with a ruler, the wound tracing method and planimetrics with the Visitrak (Smith & Nephew, London, UK) system, and the pattern-coded structured light method with the Silhouette (ARANZ Medical, Christchurch, New Zealand) system. Regression and Bland-Altman analyses were performed. The study group consisted of 23 diabetes patients with plantar foot ulcers. RESULTS: Thirty-three wounds were successfully examined. The measurement method influenced the measured area significantly (P=0.00005). The correlation coefficients between TeleDiaFoS and the ruler, Visitrak, and Silhouette methods were 0.949, 0.985, and 0.987, and the limits of agreement equaled -1.3±5.5 cm(2), -0.4±2.2 cm(2), and -0.6±2.1 cm(2), respectively. The strong linear relationships obtained can be used to convert the wound area measured with TeleDiaFoS to the corresponding value of each of the reference methods. CONCLUSIONS: The results indicate that the wound area of plantar ulcers in diabetes might be monitored effectively using the TeleDiaFoS system based on the foot scans that the patient can produce at home with no assistance of other persons.

A new imaging and data transmitting device for telemonitoring of diabetic foot syndrome patients.

BACKGROUND: Proper healing of ulcers and wounds on the feet of diabetes patients is important in order to prevent amputation. If the wound area reduction during the first 4 weeks of the treatment is not 40% or more, reevaluation of the treatment is necessary. The wound area evaluation is not complicated when the patient stays at a hospital, but when he or she goes home the physician does not have a tool allowing monitoring of the wound area. METHODS AND RESULTS: The aim of the present article is to present a new device able to take a wound picture and send it automatically to the database. This device, called the Patient's Module (PM), is also able to download data from the memories of blood pressure and blood glucose meters and send the data to the database. The PM is able to operate within the TeleDiaFoS system (developed earlier in collaboration with the Department and Clinic of Gastroenterology and Metabolic Diseases, Medical University of Warsaw, Warsaw, Poland) aimed at monitoring of treatment of patients with diabetic foot syndrome. The PM was tested on 10 type 2 diabetes patients during a 3-month period. CONCLUSIONS: The study revealed that the PM can be used as a home telemonitoring device, and the analysis of the data sent from patient's home enables the assessment of wound healing progress, giving the physician the possibility for earlier change of the treatment if the wound area reduction is not satisfactory.

Monitoring of diabetic foot syndrome treatment: some new perspectives.

Diabetic foot syndrome (DFS) is one of the major complications of diabetes, and it can lead to foot amputations. It is very important to assure good medical care for diabetic patients not only during their stay at hospital but also at home. Telecare can be one good solution for extending medical care to patients' homes. There are some reports regarding the application of new technologies in this field. The standard current model of telecare of DFS includes experts at hospital who conduct clinical examinations and decision making at a distance, in close cooperation with a visiting nurse and the patient. In the present paper a new paradigm of the DFS's telecare is introduced, which eliminates the visiting nurse. The designed and developed TeleDiaFoS system consists of a traditional database and mobile patient's module (PM) allowing for documentation of the foot images as well as the results of blood glucose and blood pressure measurements taken by the patient himself at home. A 2-year validation of the TeleDiaFoS system on 10 DFS patients (3 months each) proved its usefulness and led to acceptance of this type of technical support by patients and physicians. The designed and developed system and proposed sterilization procedure of the PM have been found to be easy to use by the patient at home.