Pre-set grid and grid app methods in measuring captured skin lesions to achieve consistency: A comparative, non-interventional validation study

YA Anisha, Potturi Ramacharan, PK Ashwini, SG Chethana, Garehatty R Kanthraj
From the Department of Dermatology, Venereology and Leprosy, JSS Medical College and Hospital, JSS Academy of Higher Education and Research (Deemed to be University) Mysuru, Karnataka, India

Date of Web Publication27-Apr-2023

Correspondence Address:
Garehatty R Kanthraj
Department of Dermatology, Venereology and Leprosy, JSS Medical College and Hospital, JSS Academy of Higher Education and Research (Deemed to be University) Mysuru, Karnataka
India
Login to access the Email id

Source of Support: None, Conflict of Interest: None

Crossref citationsCheck

DOI: 10.4103/ijd.ijd_656_22

Rights and Permissions

How to cite this article:
Anisha Y A, Ramacharan P, Ashwini P K, Chethana S G, Kanthraj GR. Pre-set grid and grid app methods in measuring captured skin lesions to achieve consistency: A comparative, non-interventional validation study. Indian J Dermatol 2023;68:235
How to cite this URL:
Anisha Y A, Ramacharan P, Ashwini P K, Chethana S G, Kanthraj GR. Pre-set grid and grid app methods in measuring captured skin lesions to achieve consistency: A comparative, non-interventional validation study. Indian J Dermatol [serial online] 2023 [cited 2023 Apr 28];68:235. Available from: https://www.e-ijd.org/text.asp?2023/68/2/235/375205

Sir,

Measurement of psoriasis and leg ulcers by counting the crossover points has been described by Bahmer et al.[1] Smartphone applications and computer software for the measurement of skin for follow-up care have been established.[2],[3] Variations in distance and angle of image capture can alter the dimensions. Attempts were made to obtain consistent images.[4] We propose, demonstrate, compare and analyse two practical methods— pre-set grid and grid app methods with respect to capturing images for maintaining constant dimensions.

This study was performed at the Department of Dermatology, JSS Hospital, JSSAHER, Mysuru from October 2020 to February 2021. Plaque Psoriasis and Tinea corporis with well-defined lesions were included.

Digital photographs were captured from two different angles and distances—overview shots from 15 and 30 cm by the principal investigator using Iphone11 (Apple.inc, California, USA) and lateral view shots from 15 and 30 cm by the second author using Oneplus7T (Oneplus Tech, China) in standard light setting without flash.[5]

In pre-set grid method, a standard graph (1 × 1 cm) was printed over a thin A3 flexible transparent sheet which served as a pre-set grid. An estimated portion of the grid was cut and placed over the lesion [Figure 1]. Our pilot trial revealed that the crossover points were constant when the grid was superimposed in a manner such that two edges of the grid touch the margin of the lesion [Supplementary Video].

Figure 1: Illustration of results of crossover point counts in pre-set and grid app method in one of the cases of psoriasis. In pre-set grid method, the grid was superimposed in a manner that two edges of the grid touched the margin of the lesion. In the grid app method, the grid automatically superimposes over the captured image. The number of crossover points remains constant irrespective of the change in distance or angle of image capture in pre-set grid method. However, in the grid app method, crossover point count varies with change in distance and/or angle

Click here to view

In the grid app method, an area calculator app (Grid#, Wang JP, China, version 2.9.1, Apple Store) was used. The captured image gets automatically superimposed by a digital grid. Area in both the methods was obtained by noting the number of crossover points[1][Figure 1]. The differences in the number of crossover points between the two methods were compared and analysed. Statistical analysis was performed by paired sample t-test and software version–SPSS 20.0 (SPSS inc., IBM, NY, USA).

There were 25 patients (15-Psoriasis and 10-Tinea corporis)—16 males and 9 females with a mean age of 42 years. The results were comparable when the pre-set grid and grid app methods were used to measure the lesion at 15 cm overview [Supplementary Table] and [Table 1]. Whereas, in 30 cm overview, 15 cm and 30 cm lateral view, the results showed significant variation between the two methods [Table 1]. The two methods are easy and take an average of two minutes.

Table 1: Summary of results obtained after independent sample t test for pre-set grid and grid app methods at 15 and 30 cm in both over and lateral views

Click here to view

Consistency in measurement is achieved irrespective of varying distance and/or angle in pre-set grid. However, in the grid app, overview image capture at a fixed distance obtains consistency.

The differences in the values of the crossover points could be due to the grid being at the level of the smartphone in the grid app method, whereas the grid in pre-set grid is at the level of the lesion.

Ill-defined lesions are limitations. We observed that glare encountered due to reflection on the gridsheet was not a barrier for point counting. Serial assessment can be performed by point counting of captured images. The two methods may have significance in future teledermatology practice.

Acknowledgment

Authors are thankful to Dr. Lancy D'souza PhD, Associate Professor in Psychology, Maharaja's College, University of Mysore, Mysore, Karnataka, India for research consultancy and statistical analysis of the data. We acknowledge JSS Academy of Higher Education and Research (JSS AHER) (deemed to be university) for their constant academic encouragement and constructive suggestions in completing this project.

Financial support and sponsorship

Nil.

Conflicts of interest

There are no conflicts of interest.

 

   References Top
1.Bahmer FA. Wound measurement made truly simple by point counting. Arch Dermatol 1999;135:991-2.  Back to cited text no. 1
    2.Kanthraj GR, Srinivas CR, Shenoi SD, Deshmukh RP, Suresh B. Comparison of computer-aided design and rule of nines methods in the evaluation of the extent of body involvement in cutaneous lesions. Arch Dermatol 1997;133:922-3.  Back to cited text no. 2
    3.Au Y, Beland B, Anderson JAE, Sasseville D, Wang SC. Time-saving comparison of wound measurement between the ruler method and the swift skin and wound app. J Cutan Med Surg 2019;23:226-8.  Back to cited text no. 3
    4.Nirmal B, Pai SB, Sripathi H. A simple instrument designed to provide consistent digital facial images in dermatology. Indian J Dermatol 2013;58:194-6.  Back to cited text no. 4
[PUBMED]  [Full text]  5.Kaliyadan F, Manoj J, Venkitakrishnan S, Dharmaratnam AD. Basic digital photography in dermatology. Indian J Dermatol Venereol Leprol 2008;74:532-6.  Back to cited text no. 5
[PUBMED]  [Full text]  
  [Figure 1]
 
 
  [Table 1]

留言 (0)

沒有登入
gif