RU2301626C1 - Method for determining skin defect surface area and controlling its changes - Google Patents

Abstract

FIELD: medicine.

SUBSTANCE: method involves photographing initial skin defect and predefined conditional reference object using digital camera. The produced digital images are saved in computer. The ratio between the number of pixels in skin defect image to that of conditional reference object pixels multiplied by reference object area is defined as skin defect area. The procedure is periodically repeated. The ratio between difference of previous and current area values to past time interval is used for controlling skin defect area changes.

EFFECT: high accuracy of measurements in noninvasive mode.

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Description

The present invention relates to medicine, namely to surgery, and can be used to measure the area of skin defects of various configurations and origin, including wounds, ulcers, burns, frostbite, and also control their changes.

The need to determine the area of a skin defect and control the dynamics of its change arises both in the treatment of patients with damage to the skin of any origin, and in conducting experimental comparisons of the effectiveness of various methods of treating wounds, ulcers and thermal injuries.

Monitoring the change in the area of a skin defect refers to the tasks that surgeons and other doctors of the surgical profile solve daily. In this case, objective methods carry out only an initial assessment of a skin defect, and control the change in area is carried out subjectively. This often leads to an incorrect interpretation of the dynamics of the development of the pathological process and negatively affects the results of treatment. Inevitably, the reliability and quality of medical records is affected. The ongoing introduction of information technology in clinical medicine requires adequate changes in traditional methods.

Do not forget about the increasing pace of the creation of various pharmaceuticals for the treatment of wounds, ulcers and thermal injuries, which determine an increase in the number of experimental studies aimed at comparing the effectiveness of their use. The ability to quickly and accurately compare the area of skin defects during treatment with various pharmaceutical agents is of particular importance in such conditions.

Thus, there is an objective need to create a new way to determine the area of a skin defect and control the dynamics of its change, corresponding to the current level of development of information technologies.

A known method for determining the area of wounds (trophic ulcers) and control its changes [O.O. Biliaieva, V.V. Yatsun, V.V. Biliaiev, V.A. Nevzhliad. Method for assessing efficacy of treating trophic ulcers. Patent number: UA 64171. Publication date: 02/12/2004. Priority number: UA 20030031853 20030303], implemented by measuring the surface of the lesion by scanning the imprint of a skin ulcer on office paper.

The method has the following disadvantages: a) contact with the wound, which imposes additional requirements on the contacting agent (paper) for sterility; b) contamination of paper with biological material, leading to the need to comply with additional safety measures when working with it, as well as during its disposal; c) the inability to use for skin defects whose dimensions exceed the dimensions of a sheet of paper or a scanning device in at least one direction.

The closest analogue is the method for determining the area of wounds and controlling its changes [E.P. Bezuglaya, S.G. Belov, V.G. Gunko, B.M. Datsenko, A.V. Datsenko and others. Theory and practice of local treatment purulent wounds. Kiev: Zdorovye, 1995. P.64], realized by photographing a wound with an analog camera with a grid, 1 cm ^{2 of} which consists of 25 squares. Comparing repeated photographs of wounds with the calculated area, the authors establish the percentage of its reduction per day according to the well-known formula [M.F. Kamaev. Infected wound and its treatment. M.: Medicine, 1970. P.67].

The method has the following disadvantages: a) the contact of the wound with the measuring grid, which imposes additional requirements for the contacting agent (grid) for sterility; b) the limited resolution of the method is 1/25 cm ² ; c) manual calculation of the number of squares of the grid, which is a laborious and lengthy process with a large area of the wound.

The task is to create a method that allows measurements to be made without contact, with high accuracy and speed, designed both for individual control of patient treatment and for experimental testing of the effectiveness of drugs, as well as with the ability to easily integrate into the documentation of a computer (computer).

The essence of the invention lies in the fact that the original skin defect and the specified conditional area standard are photographed using a digital camera, the resulting digital image is transferred to a computer and the ratio of the number of points in the image of the skin defect to the number of points in the image of the conditional area standard multiplied by the area of the standard is determined as the area of the skin defect, then the procedure is periodically repeated and the change is controlled in relation to the difference between the previous and current area values to the elapsed time interval area of skin defect.

The technical result of the invention is the creation of a method for planimetric examination of patients with defects in the skin, suitable for mass measurements with high accuracy, which allows to adjust the therapy and achieve individualization of treatment. Improving the technical results of treatment is ensured by the operational instrumental and mathematical processing of data, contactless techniques for taking data in dynamics, reliable and easy access to the database in order to monitor the progress of treatment.

The proposed method is as follows:

a) photographing on a digital device the skin defect and the adjacent conditional standard of the area of the given color No. 1 (the standard is the square of the accepted size - 10 × 10 mm, 20 × 20 mm, etc.);

b) the resulting digital image is transferred to a computer;

c) change the color of the image points that are not related to the conditional standard of the area and the skin defect, for a given color No. 2;

g) determine the number of points of the digital image related to the conditional standard area, by counting the number of color points No. 1;

d) determine the number of points of the digital image that are not related to the conditional standard area and skin defect, by counting the number of color points No. 2;

f) calculate the number of points in the image of the skin defect as the difference between the total number of points of the digital image and the sum of the number of points of color No. 1 and color No. 2;

, где S_{дефекта} - площадь дефекта (мм²), S_{эталона} - эталона площадь эталона (см²), N_{дефекта} - количество точек в цифровом изображении дефекта, N_{эталона} - количество точек в цифровом изображении эталона.g) calculate the area of the skin defect according to the formula:

where S of the _defect is the area of the defect (mm ² ), S of the _standard is the standard, the area of the standard (cm ² ), N of the _defect is the number of points in the digital image of the defect, N of the _standard is the number of points in the digital image of the standard.

h) make a series of digital photographs of a skin defect, as described above, with a predetermined time interval between them (from several hours to several days);

i) calculate the dynamics of changes in the area of the skin defect as the ratio of the difference between the previous and current values of the area to the elapsed time interval.

The method was tested on 30 patients of the basic departments of the Department of General Surgery of the Kuban State Medical Academy.

Example. Patient P., 37 years old (medical history No. 32349), was admitted to the purulent-septic surgery department of the Regional Clinical Hospital No. 1 of Krasnodar on 09/19/2005. Upon admission, the diagnosis was established: "Paraarticular phlegmon of the right lower limb." Conducted surgical treatment. A digital camera took a photograph of the resulting defect in the skin and conditional area standard. The number of points in a digital image of a skin defect (N = 543601) and in a digital image of a conditional area standard (N = 252748) were determined. The calculation of the area of the skin defect dividing the number of points in the digital image of the skin defect by the number of points in the digital image of the conditional area standard and multiplying the result by the area of the conditional standard (25 cm ² ). It is established that the area of the wound is 53.77 cm ² . To close the wound, the method of dermotension was chosen. Stitches were applied that were tightened once every 2 days. Repeated measurements of the wound area were carried out every two days. The first 8 days, the wound area was rapidly reduced, but on 10-12 days there was a significant decrease in the rate of decrease in skin defect (table). Thanks to constant monitoring of the area of the wound, it was possible to timely establish the futility of continuing dermatotension and to change the treatment method. The autodermoplasty method was chosen with a free perforated split skin flap. The autoderm graft has taken root and the patient was discharged from the hospital after 9 days with recovery.

The dynamics of the closure of the wound of patient P. The time from the start of treatment, days. The number of points in the image of the wound, pcs. The number of points in the image of the standard area, pcs. The area of the wound, cm ² 0 543601 252748 53.77 four 416625 261568 39.82 6 350145 269924 32,43 8 331347 278537 29.74 10 309835 267931 28.91 12 313149 280801 27.88

Using the proposed method allows to obtain the following effect:

- accelerating the implementation of planimetric methods for examining the patient and reducing the burden on the doctor;

- an adequate assessment of the dynamics of changes in the area of skin defects allows you to adjust the therapy and achieve a speedy recovery of the patient;

- the non-contact method eliminates the problems associated with both the sterility requirements of agents in contact with the wound, and with the requirements for the disposal of waste contaminated with biological fluids (blood, pus);

- the objectivity of the method allows you to avoid legal doubts about the correctness of the treatment of the patient in case of contentious cases;

- compliance with the standards of modern information technology allows you to integrate the results into electronic computer documentation.

Claims (1)

A method for determining the area of a skin defect and controlling its changes, including photographing, characterized in that the original skin defect and a predetermined conditional area standard are photographed using a digital camera, the digital images obtained are transferred to an electronic computer and the ratio of the number of dots in the image of the skin defect to the number points in the image of the conditional area standard, multiplied by the area of the standard, is defined as the area of the skin defect, then the procedure is periodically repeated and with respect to p The units of the previous and current area values to the elapsed time interval control the change in the area of the skin defect.