Abstract
Immediate assessment of surgical incisions is an important component of wound management, and the development of relevant technologies has the potential to address these challenges. Smartphone‐based handheld thermal imagers can collect infrared radiation from the skin to monitor local blood perfusion and metabolic levels in incisions. Here, we used this imaging technology for early assessment of healing progress and potential for predicting the healing status of thoracic surgical incisions. Thermal image acquisition and temperature extraction were performed on 40 patients for 7 consecutive days postoperatively, and visualised early warning information was observed, with temperature and temperature readings showing non‐linear trajectory changes during the measurement period, and temperature readings on day 4 achieving high prediction of healing status at 1–2 months capability with sensitivities and specificities of 91.67% and 85.71%, respectively, suggesting a promising clinical application of portable thermography for assessing incision healing dynamics and providing a scientific basis for later artificial intelligence‐driven decision algorithms.
Keywords: chest incision, healing progress, infrared thermography, prediction, wound care
1. INTRODUCTION
A related study in 2014 showed that nearly 15% of patients were diagnosed with wound‐related infections, with surgical wound infections accounting for the largest proportion (4.0%), and the proportion of surgical wounds that chronically did not heal (3.0%) was second only to diabetes‐related infections, and surgical wounds were the most expensive in terms of medical expenditures. 1 We understand that impaired surgical wound healing can be complicated by incision‐related complications such as incisional infections, fat liquefaction, and hypertrophic scarring, adding additional medical burden. 2 , 3 Current wound management practices include the TIME clinical decision tool, which assesses four dimensions: tissue, infection/inflammation, moisture, and wound margins, 4 and which guides the principles of wound management for all types of wounds. The lack of accurate and specific medical diagnosis and appropriate treatment management plans for surgical wounds presents a challenge to the goal of systematising, standardising, and objectifying clinical wound care. 4 , 5 Although tools have been proposed for the assessment of acute surgical wounds, such as risk assessment scales that assign values to subjective information, ultrasonography to aid in the diagnosis of swelling and bruising, and MRI scans for complex wounds, they are more or less limited by radiation exposure, high cost, poor accessibility, and lack of clinical implementability. Some studies have started to monitor the levels of PH, temperature, C‐reactive protein, oxygen, etc. 6 From the assessment of wound microenvironment imbalance. However, the precise measurement of these indicators is still to be explored, such as the development and application of new tools and protocols for monitoring and optimising treatment.
Already superior in industry, thermography has been widely used in medicine for its convenient, non‐invasive and efficient imaging characteristics, such as predicting the healing potential of burns, 7 pressure sores 8 and most chronic wounds. Thermography displays the temperature distribution of the skin in a thermal image by examining the infrared reflections from the skin. 9 Previous studies have shown that wound characteristics can be observed in infrared thermography, which is expected to serve as an early diagnostic “biomarker” to warn of later healing problems such as incisional infections. 10 Some studies have identified the healing trajectory as a determinant of healing outcome. 11 In this study, we used a smartphone‐based thermal imaging camera to assess surgical incisions, which provides a convenient thermometric experience and excellent imaging compared to traditional thermal imaging cameras, and is user‐friendly for nurse‐led wound assessment due to its high degree of operability and readability of results. We use this emerging imaging technology to obtain thermal images and thermal characteristics of surgical wounds for 7 consecutive days postoperatively, with the main purpose of analysing the initial healing trajectory of different patients and exploring how incision temperature affects healing, and furthermore, we needed to evaluate the early performance and reliability of infrared thermography in predicting incisional problems to better guide clinical decision making.
2. MATERIALS AND METHODS
2.1. Patient selection
This was a retrospective cohort study that included 46 patients admitted to A tertiary general hospital between June 5, 2022, and July 10, 2022, for thoracic surgery in parallel with surgical treatment, including conventional open chest, thoracoscopic and robotic‐assisted lobectomy, radical oesophageal cancer, radical pulmonary herpes, and resection of mediastinal lesions, and there was no explicit age restriction. However, a surgical incision length of at least 3–4 cm is required. Patients who could not provide informed consent, had a history of hypertrophic scarring, had serious hematologic disorders or other vascular comorbidities, were missed in the follow‐up program and received negative wound pressure therapy were excluded. The study was approved by the Medical Ethics Committee of the First Hospital of Lanzhou University (Number:LDYYLL2022‐413). Included patients received a minimum of 6–7 days of thermographic evaluation during hospitalisation and were available for follow‐up within 1–2 months after surgery, with the collection of electronic photographs including the visual state of the incision and related healing status interviews. A total of 6 patients were excluded from this study, including 2 patients with a hospital stay of less than 6 days, 3 patients with missed visits, and 1 patient with missing thermographic scan data, resulting in the inclusion of 40 patients who met the study needs.
2.2. Healing definition
Surgical incision healing outcome was determined by two surgeons through in‐hospital visual evaluation, visual photographs at the two‐month postoperative follow‐up, and healing‐related interview content. Poor healing was classified as any of the following: (1) delayed healing: the chest incision was not closed after 8 days postoperatively, the tissue integrity was not repaired, the skin tissue at both edges of the incision was not fully adhered, or there were obvious signs of infection and fat liquefaction in the incision; (2) keloid or hypertrophic scar: the incision tissue was above the skin surface, beyond the original injury site, and continued to grow during the 2‐month follow‐up period after surgery. The assessment data were obtained from interviews and electronic photographs; (3) chronic wounds: wounds that had not healed after more than one month of treatment and had no tendency to heal. Telephone interviews were conducted by wound/stoma specialist nurses at approximately one month and two months postoperatively for patients who had undergone serial thermographic wound scans postoperatively, in which the interviews involved information on healing beyond static photographs such as itchiness, local appearance, and treatment history related to incision healing, which should be recorded in detail to assist the clinician in diagnosis.
2.3. Thermal imager
The thermal imaging camera(T3Pro, Thermal Camera for Smartphone, InfiRay, China) has its USB type‐C interface to connect to electronic devices such as smartphones or iPads and generate temperature‐readable thermal spectra, as shown in Figure 1. The camera weighs less than 40 g, ultra‐low power consumption (<0.5 W), and has the following dimensions: 49.5 × 26 × 27.5 mm. It features high pixel, high frame rate, clear and smooth imaging with 384 × 288 array, 110 000 pixels, frame rate up to 25 Hz, and various colour palettes available to meet different application scenarios. This thermal imaging camera has a professional APP for point/line/plane temperature measurement NETD ≤ 60 mK, with measurement accuracy of ±2°C, and the measurable temperature range is approximately −20°C to 120°C. Thermal imaging acquisition is strictly required to be performed in a general ward without air conditioning, with appropriate temperature and humidity (18–22°C, 50–60%), and without surface disinfection before measurement to avoid causing pseudo hypothermic zones. 12 This thermography allows for six temperature readings to be manually acquired in the same image, four incision temperatures and two surrounding healthy skin temperatures. The incision temperature readings can be acquired in equal proportion to the length of the incision as measured by the scale (Generally 4–5 temperature readings to be obtained), and the distinct blue‐green area on the incision is retrieved to determine the lowest incision temperature. The surrounding healthy skin temperature is then the average of the two temperatures obtained 3CM outside the incision. To observe the healing status of the incision, we also calculated the temperature difference between the incision and the surrounding skin based on the data acquired from the images (∆T = T surrounding–T incision).
FIGURE 1.
The left figure shows the sampling schematic, and the right figure shows the thermal spectrum showing the temperature readings of the incision, the edge of the incision and the reference area around the incision
2.4. Study procedures
Highly trained fellows (clinical nurses) used smartphone thermography to continuously capture the thermal characteristics of the surgical incision site before surgery and from the first postoperative day to the discharge of the patient. They also simultaneously capture and store traditional visual photographs as well for visual assessment and post‐analysis. A box showing regional temperature averages was outlined at the surgical site preoperatively to record preoperative baseline temperature levels for reference. Acquisition on the first postoperative day (not the day of surgery) is usually performed within 12–24 h postoperatively due to unpredictable exogenous influences (e.g, anaesthesia, surgical stress, and other factors) and for incisional protection in the early period. The surgical incision was cleaned and dried prior to the thermographic scan and dressings were removed, including ointments, blisters, and necrotic skin; the acquisition height was controlled within the 20–30 cm range; the nurse removed the grill lamp treatment and other external heat sources 10 min prior to the measurement. The colour palette (white‐hot, rainbow and other colour modes) and the unit of temperature measurement (°C or °F) were selected before the temperature measurement, and the lens focal length was manually adjusted at a constant height to obtain a clear visual colour temperature map of the incision area and to manually identify the region of interest (ROI) and healthy skin (reference area) temperature values of the incision, which should be selected at least 3 cm outside the incision, considering local congestion. The photo acquisition should be repeated several times in order to reduce errors and to select the ideal image. The resulting images can be stored in a local album on a smartphone for easy analysis and transfer. Patients were followed up by telephone 1–2 months after discharge and standardised photographs were transmitted back for visual assessment, and two clinicians made outcome judgements of patient incision healing; inconsistent judgements of outcome were made by a third physician with an associate or higher title for final determination.
2.5. Statistical analysis
Data were analysed using SPSS, Version 26.0 (IBM, Armonk, New York). For continuous measures expressed as means and standard deviations and for counts expressed as cases and percentages, the Wilcoxon rank‐sum test, t‐test, χ 2 test, or Fisher exact probability test were used to compare the demographic information and incisional temperature characteristics of patients in the healing and non‐healing groups. In addition, to analyse the reliability of thermal imaging to discriminate healing potential, we created subject operating characteristic curves (ROC curves) for two categories of minimum incisional temperature and temperature difference at 1–7 days postoperatively and calculated the area under the curve (AUC), sensitivity, specificity, and best cut‐off value. P < .05 were considered to be statistically significant (see Figure 2).
FIGURE 2.
Immediate images taken by the thermal imaging camera, where labels (A) and (B) denote two different patients and their standard postoperative photographs, (A1–A7) denotes the visual thermal images of patient A from postoperative day 1 to postoperative day 7, and (Aa) denotes the post‐healing photograph of patient A. As above, (B1–B6) and (Bb) denote the corresponding images of patient B. Both patients were non‐healing, and patient A had an incision‐related infection; patient B had delayed incision closure
3. RESULTS
3.1. Participants and their characteristics
A total of 40 patients who met the inclusion criteria were enrolled in this preliminary study. According to a comprehensive analysis of patient follow‐up information and personalised interview data, a total of 28 (70%) wounds healed well within 4–8 weeks (healing group), and 12 (30%) wounds showed poor healing (non‐healing group). There were no statistical differences in the clinical data between the two groups except for the length of hospital stay (Table 1).
TABLE 1.
A comparison of the general clinical data between the two groups of patients [n (%), x ± s, M(IQR)]
| Index | Healed group | Unhealed group | t/χ 2/Z | P |
|---|---|---|---|---|
| Gender | 0.317 | .573 | ||
| Male | 16 (57.14) | 8 (66.67) | ||
| Female | 12 (42.86) | 4 (33.33) | ||
| Age (years) | 55.11 ± 14.79 | 58.25 ± 10.86 | −0.662 | .512 |
| Body mass index (kg/m2) | 23.45 ± 2.43 | 23.64 ± 3.90 | −0.157 | .878 |
| Diabetes mellitus | 2 (7.14) | 2 (16.67) | 0.847 | .358 |
| Hypertension | 7 (25.00) | 5 (41.67) | 1.111 | .292 |
| Smoking history | 6 (21.43) | 4 (33.33) | 0.635 | .426 |
| Radiotherapy history | 3 (10.70) | 2 (16.67) | 0.272 | .602 |
| Steroids medication history | 5 (17.86) | 4 (33.33) | 1.154 | .283 |
| Immunosuppressant medication history | 9 (32.14) | 6 (50.00) | 1.143 | .285 |
| Disease type | 0.127 | .722 | ||
| Malignant lesions | 18 (64.29) | 7 (58.33) | ||
| Benign lesion | 10 (35.51) | 5 (41.67) | ||
| Operation time (h) | 2.54 ± 1.14 | 2.94 ± 1.07 | −1.042 | .304 |
| Intraoperative blood loss (ml) | 89.46 ± 39.39 | 125.97 ± 82.58 | −1.462 | .167 |
| LOS (d) | 15.07 ± 5.60 | 20.42 ± 8.61 | −2.342 | .025 |
| Incision length (cm) | 6.05 ± 1.18 | 6.20 (5.63,23.5) | 1.568* | .117 |
| Stitching method | 0.204 | .651 | ||
| Interrupted suture | 19 (67.86) | 9 (75.00) | ||
| Running suture | 9 (32.14) | 3 (25.00) | ||
| WBC (109/L) | 14.01 ± 4.33 | 13.75 ± 4.48 | 0.171 | .865 |
| ALB (g/L) | 39.34 ± 3.93 | 37.60 ± 4.14 | 1.262 | .215 |
| PRE‐OP temperature (°C) | 33.9 ± 0.9 | 34.0 ± 0.8 | −0.222 | .825 |
Abbreviations: ALB, Albumin; LOS, Length of stay; PRE‐OP, Pre‐operative; WBC, White Blood Cell.
Indicates the use of nonparametric rank sum test; t‐test was used for other continuous data.
3.2. Thermal imaging figure
Two patients with poor healing are used as examples to demonstrate the thermal image characteristics under visualisation. Patient A, female, underwent thoracoscopic right upper lung lobectomy, and a snapshot taken 7 consecutive days postoperatively showed significant hypothermic areas in the incision area, particularly significant on postoperative days 3, 4, and 5. The patient reported signs of infection in the incision after discharge, and the incision healed at about one month after treatment with broad‐spectrum antibiotics. Patient B, female, underwent open thoracic diaphragmatic hernia repair; postoperative snapshots for 6 consecutive days showed varying degrees of “cold spots” in the early stages of healing (days 1–4), delayed closure of the incision ends resulting in failure to remove the stitches as scheduled, and the patient reported mild local pruritus (Figure 3).
FIGURE 3.
The trends of temperature characteristics and ROC curves. (A and B) represent the trends of two indicators of incisional minimum temperature and temperature difference with postoperative time, respectively; (C and D) represent the potential of incisional minimum temperature and temperature difference to predict incisional healing at POD 4 and POD 7 days, respectively, in cases derived from the 12 patients with poor healing in this study. POD, Post‐operative Days, Number of days after surgery
3.3. Temperature characteristics
The repeated‐measures ANOVA showed statistically significant differences (P < .05) in the time factor, grouping factor, and interaction factor for both incision minimum temperature and temperature difference, and there were statistically significant differences (P < .05) in the incision minimum temperature and ΔT values between the healed and unhealed groups, except for POD2, and especially in POD4 and POD7 on two days (P < .0001) (Table 2).
TABLE 2.
A comparison of temperature levels at different time points between the two groups (x ± s)
| Index | Healed group | Unhealed group | F | P |
|---|---|---|---|---|
| Minimum temperature (°C) | ||||
| POD1 | 32.3 ± 1.6 | 30.8 ± 1.7 | 8.194 | .007 |
| POD2 | 32.9 ± 1.3 | 31.9 ± 2.2 | 2.915 | .096 |
| POD3 | 32.8 ± 1.5 | 31.3 ± 2.3 | 6.387 | .016 |
| POD4 | 32.9 ± 1.6 | 30.0 ± 1.5 | 26.150 | .000 |
| POD5 | 33.4 ± 1.1 | 32.0 ± 1.2 | 12.883 | .001 |
| POD6 | 33.5 ± 0.7 | 32.2 ± 1.4 | 12.367 | .001 |
| POD7 | 33.8 ± 0.9 | 32.4 ± 0.8 | 21.878 | .000 |
| F | F T = 12.056, F I = 2.681 | |||
| P | P T < .001, P I = .031 | |||
| Temperature difference (°C) | ||||
| POD1 | 2.3 ± 1.1 | 3.1 ± 1.1 | 4.509 | .04 |
| POD2 | 1.7 ± 0.7 | 2.2 ± 1.2 | 3.163 | .083 |
| POD3 | 1.6 ± 0.8 | 3.0 ± 1.4 | 16.225 | <.001 |
| POD4 | 1.7 ± 1.0 | 3.8 ± 1.2 | 31.782 | <.001 |
| POD5 | 1.2 ± 0.7 | 2.5 ± 1.2 | 17.899 | <.001 |
| POD6 | 0.8 ± 0.5 | 1.7 ± 0.9 | 17.822 | <.001 |
| POD7 | 0.5 ± 0.3 | 1.3 ± 0.5 | 45.954 | <.001 |
| F | F T = 44.467, F I = 4.028 | |||
| P | P T < .001, P I = .004 | |||
Abbreviations: Data were analysed using repeated measures ANOVA; I, Interaction (group × time); POD, Post‐operative Days, Number of days after surgery; T, Time.
3.4. Temperature change trajectory graph and ROC curve
The incision temperature showed a trend of increasing then decreasing then increasing. On the contrary, the temperature difference showed a trend of decreasing then increasing then decreasing, and the non‐healing group decreased significantly compared with the healing group; the ROC curves of each index were plotted, among which the predictive validity of POD4 and POD7 for two days was better(Figure 4, Table 3).
TABLE 3.
The predictive value of minimum temperature and temperature difference
| Index | Area | P value | Cut‐off value | Youden's index | Sensitivity (%) | Specificity (%) |
|---|---|---|---|---|---|---|
| Minimum temperature (°C) | ||||||
| POD1 | 0.746 | .015 | 31.6 | 0.429 | 75 | 67.86 |
| POD2 | 0.674 | .084 | 32.0 | 0.405 | 58.33 | 82.14 |
| POD3 | 0.743 | .016 | 30.7 | 0.595 | 66.67 | 92.86 |
| POD4 | 0.880 | <.001 | 30.7 | 0.798 | 83.33 | 96.43 |
| POD5 | 0.854 | <.001 | 33.1 | 0.655 | 83.33 | 82.14 |
| POD6 | 0.853 | <.001 | 32.6 | 0.643 | 75 | 89.29 |
| POD7 | 0.885 | <.001 | 32.7 | 0.679 | 75 | 92.86 |
| Temperature difference (°C) | ||||||
| POD1 | 0.676 | .082 | 3.1 | 0.333 | 58.33 | 75 |
| POD2 | 0.649 | .140 | 2.8 | 0.333 | 33.33 | 100 |
| POD3 | 0.771 | .007 | 2.9 | 0.595 | 66.67 | 92.86 |
| POD4 | 0.908 | <.0001 | 2.4 | 0.774 | 91.67 | 85.71 |
| POD5 | 0.832 | .001 | 1.3 | 0.631 | 91.67 | 71.43 |
| POD6 | 0.887 | .0001 | 1.3 | 0.643 | 75 | 89.29 |
| POD7 | 0.969 | <.0001 | 0.8 | 0.893 | 100 | 89.29 |
Note: POD, Post‐operative Days, Number of days after surgery; The data in the table are calculated from the ROC curve(receiver operating characteristic curve) correlation analysis.
4. DISCUSSION
The process of tissue repair and healing, including surgical wounds, often consists of three consecutive and overlapping phases: the inflammatory phase (2–5 days), the proliferative phase (5 days to 3 weeks), and the remodelling phase (3 weeks to years), 13 of which the assessment of the initial inflammatory and proliferative phases often plays an important role. We often lack an objective evaluation system for the early assessment of surgical incisions, especially for early warning information regarding delayed closure of the incision, potential infection and other wound complications. Many patients with incisional problems do not exhibit typical signs and symptoms, and early detection of wound deterioration and necrosis cannot be achieved by traditional visual skin tissue and empirical assessment alone, requiring a desperate search for low‐cost and easy‐to‐implement detection methods.
Studies have shown that hypothermia can affect the physiological state of a wound and that a microenvironment that alleviates hypothermia and maintains normal body temperature can promote wound healing. 14 Second, the assessment of wound physiological parameters such as temperature is objective, standard and clinically relevant, 15 and it plays a vital role in the function of every system of the body, mainly affecting cellular function and activity. 6 During the inflammatory phase, increased acute wound temperature increases local dermal blood flow and subcutaneous oxygen tension, resulting in an environment conducive to wound healing, 16 , 17 whereas healing is delayed when the temperature of the wound bed is lower than the core temperature, and studies have also reported that such hypothermia is associated with wound infection. 18
Thermography is fast, non‐contact, passive and non‐harmful radiation, 19 and its skin temperature detection has occupied the field of diabetic foot, fever, cancer, eye disease, pain, and has successively developed computer‐aided systems to facilitate medical diagnosis. 20 Thermography collects infrared thermal radiation from the skin to visualise and monitor blood circulation. 21 When the skin's thermal properties and physiological functions change, they can be expressed as a specific colour distribution. Relevant clinical trials have repeatedly demonstrated that abnormal “red dots” and “blue dots” on thermal images are highly predictive of tissue defect closure. 18 In these cases, the red colour suggests that clinicians need to pay further attention to incisional infections, 10 and the immediate snapshot of thermal imaging reduces the uncertainty of visual assessment. Thermography reflects blood flow distribution and tissue perfusion on a macroscopic scale, 22 with low temperatures correlating with perfusion levels and high temperatures correlating with inflammation. The initial phase of surgical healing often involves the redistribution of blood flow and the manifestation of the inflammatory phase, during the initial inflammatory process, the wound site is usually hypoxic, mainly due to impaired oxygen delivery due to disruption of the periwound vascular system, and furthermore, the rapid accumulation of inflammatory cells to the hypoxic area can in turn. However, this hypoxia is only transient and successful healing often requires repair of the local microvascular system to restore normoxic conditions, 23 which in turn promotes collagen and fibroblast production and transformation. Continued hypoxia reduces collagen matrix production, delays granulation tissue formation and decreases wound contraction, even to the point of chronic non‐healing wounds. 24 Therefore, a non‐linear trajectory change in the healing time curve was seen in this study. The incision temperature in the non‐healing group showed a significant decrease in the postoperative 3 and 4 days, mainly due to low collagen deposition associated with the persistence of ischemia and hypoxia, at which time targeted wound treatment and care, such as strategies to stimulate vascular endothelial growth factor, local wound oxygen therapy and necrotic tissue debridement, should be directed to promote revascularization of the incision and surrounding tissues and rapidly promote extracellular matrix production to achieve initial closure. Another plausible explanation is subepidermal moisture (SEM), an early inflammatory response often accompanied by vasodilatation and tissue leakage, resulting in increased subcutaneous fluid content, 25 which may show a local blue‐green signal in the thermal image, and a large amount of tissue fluid accumulation may contribute to a rapid deterioration of the healing environment, and this monitoring technique may provide specialist decision support such as negative pressure wound treatment. A comparison of consecutive postoperative snapshot images showed significant shrinkage of the “cold spot” area after four days, which could reflect the healing rate and potential of the patient. Therefore, this study concluded that local incisional thermometry with portable thermography could visualise and monitor incisional healing dynamics and provide early warning of non‐benign healing further to guide clinical decision‐making, such as thermal therapy. The skin temperature of different healthy people varies, mostly in the range of 33–36°C, and the predictive efficacy of incision temperature alone may not be good, compared with this, the temperature difference between the incision and the surrounding skin has a better predictive ability and can be used as an independent predictor of poor incision healing, and the study analysed that patients may have healing problems when the lowest temperature of POD4 incision is less than 30.65°C or the temperature difference is greater than 2.35°C. impairment; at POD7 incision temperature less than 32.65°C or temperature difference greater than 0.75°C, it is reasonable to suspect that patients will have poor healing. Some studies have shown that 33°C is the critical temperature level required for normal cellular activity, 26 and in other studies have found that a temperature difference of greater than 0.95°C (95% CI: 0.32, 1.58°C) on day 7 is just enough to distinguish patients with wound infection from those who heal normally, and have shown that a temperature difference of 1°C can increase the chance of infection by a factor of 3. 27 Based on this initial exploration, future studies should be conducted prospective cohort studies to further explore how early temperature trends and thermal image features affect the short‐term and final prognosis of incisions, and to perform clinical validation in a large sample‐based multicenter to build a robust system and model for thermographic assessment of surgical incision healing, to provide experience and data sets for the future development of an artificial intelligence‐driven decision algorithm based on thermographic scans for effective differential diagnosis and prognosis prediction, and in future, such performance metrics can be extended to other anatomical sites and patient populations.
The present study has some limitations. First, surgical wound healing is a continuous, complex, and long‐term process, and there is no rigorous “gold standard” for complete healing, so only short‐term healing outcomes in the first two months were used as a basis for grouping based on the need for the study, and subsequent studies will continue to explore its value for long‐term prognosis. Secondly, this study is a retrospective analysis and potential effects not related to the microenvironment of wound healing cannot be ruled out, and the study needs to develop content including sample size and baseline data. Again, the results of this study should be validated and supplemented by more sophisticated thermal imaging cameras and large sample studies.
5. CONCLUSION
Smartphone‐based infrared thermography can bridge the gap of traditional visual assessment by monitoring the healing progress of most wound types, including surgical incisions, in real time, identifying specific risk and deterioration information, and with a high degree of accuracy and reliability under controlled spatial distance and environmental conditions, thermographic assessment can be used as an auxiliary diagnostic tool in the field of wound care to further promote precision care programs. In addition, wound photography is critical for reliable assessment and management, as it can be easily stored, shared and accessed to enrich wound care cases and build a complete surgical wound care system.
CONFLICT OF INTEREST
The authors declared no potential conflicts of interest.
ACKNOWLEDGEMENT
First, our project is funded by the Natural Science Foundation of Gansu Province (21JR1RA092 & 21JR1RA118) and the Gansu Provincial Youth Science and Technology Foundation (18JR3RA305 & 21JR1RA107), and we greatly appreciate the support for our project. Second, my deepest gratitude goes to Professor Minjie Ma, my tutor, for his constant encouragement and guidance. He has walked me through all the stages of the writing of this thesis. Without his consistent and illuminating instruction, this thesis could not have reached its present form. I owe much to my friends and classmates for their valuable suggestions and critiques which are of help and importance in making the thesis a reality. Finally, we would like to thank the Department of Thoracic Surgery of the First Hospital of Lanzhou University, Gansu University of Chinese Medicine, Key Technology Development and Application of Thoracic Surgery Specialty Gansu Province International Science and Technology Cooperation Base and Medical Quality Control Center of Thoracic Surgery in Gansu Province for their theoretical and practical support of this study, which can continue to support the next research work in the future.
Li F, Wang M, Wang T, et al. Smartphone‐based infrared thermography to assess progress in thoracic surgical incision healing: A preliminary study. Int Wound J. 2023;20(6):2000‐2009. doi: 10.1111/iwj.14063
DATA AVAILABILITY STATEMENT
The datasets used and/or analyzed during the current study are available from the corresponding author on rea‐sonable request.
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Associated Data
This section collects any data citations, data availability statements, or supplementary materials included in this article.
Data Availability Statement
The datasets used and/or analyzed during the current study are available from the corresponding author on rea‐sonable request.