Quantitative Studies of Diabetic Foot Ulcer Evolution Under Treatment by Digital Stereotactic Photography

Abstract

Background: Imaging the lower extremity reproducibly and accurately remains an elusive goal. This is particularly true in the high risk diabetic foot, where tissue loss, edema, and color changes are often concomitant. The purpose of this study was to evaluate the reproducibility of a novel and inexpensive stereotaxic frame in assessment of wound healing.

Methods: The main idea is to keep constant and reproducible the relative position of extremities related to the sensor used for the examination during a serial studies by stereotaxic digital photographic sequence. Ten healthy volunteers were evaluated at 10 different time moments to estimate the foot position variations in the stereotaxic frame. The evolution of 40 of DFU patients under treatment was evaluated before and during the epidemical grow factor intralesional treatment.

Results: The wound closing and granulation speeds, the relative contribution of the contraction and tissue restauration mechanism were evaluated by stereotaxic digital photography.

Conclusions: The results of this study suggest that the stereotaxic frame is a robust platform for serial study of the evolution of wound healing which allow to obtain consistent information from a variety of visible and hyperspectral measurement technologies. New stereotaxic digital photography evidences related to the diabetic foot ulcer healing process under treatment has been presented.

Keywords: diabetic foot ulcer; imaging; quantitative evolution; serial studies.

Figure 1.

Stereotaxic frame views. (A) An isometric view schema. (B) A real photographic lateral view. (C) A general photographic view with the patient in the examination position. In Figure A, (1) is the base, (2) is the tower to fit the leg position, (3) is the tower were is collocated the measurement instrument or sensor. The measurement instrument can be move around the arc (5) or the axes (6).

Figure 2.

As example five photographic sequences as time function. The cross is an external marker in order to makes the pixel-dimension calibration. The first columns of photographs at the left correspond to lesion before the treatment. INA, HCC, and SMLAS are patients corresponding to Camilo Cienfuegos Provincial Santis Spiritus Hospital and Sierra Maestra Policlinic, respectively.

Figure 3.

Normalized kinetics curve wound (A) and granulation (B) areas in depends time of the treatment for some of the patients.

Figure 4.

Kinetic curve analysis of a typical case. The curve in black is the lesion area changing as function of the treatment time. Similarly the red curves represent the growing granulation area as consequence of the EGF treatment. The most important obtained information is the slope of these curve which represent the rate of change of the lesion closing process and the increasing the extent of the new tissue.