ABSTRACT
Background:
Negative pressure wound therapy (NPWT) is the treatment of choice for diabetic foot ulcers (DFUs), and the role of NPWT in the management of DFU is limited. The aim of the study was to compare the effects of NPWT versus conventional dressing (CD) on wound healing in DFU.
Materials and Methods:
A total of 55 patients were included and divided into two groups: 23 patients were treated with NPWT and 32 patients with CD. The NPWT dressings were changed every 7 days, while the CDs were changed daily. Wound culture sensitivity, wound size, granulation tissue, and pain evaluation (assessed by Visual Analog Scale) were all measured at the start and 3 weeks or until the ulcer was healed. The wound margin temperature was measured at four random sites for thermometric evaluation, and normal limb temperature was also measured for comparison. Patients’ satisfaction and treatment costs were also compared.
Results:
On days 14 and 21, the wound size was reduced significantly in the NPWT group (P < 0.001 and P < 0.001, respectively). The percentage reduction in wound size from baseline to days 7, 14, and 21 was significantly higher in the NPWT group (P = 0.013, P = 0.001, and P = 0.029, respectively). On days 7, 14, and 21, the granulation tissue score was significantly higher in the NPWT group (P = 0.001, P = 0.001, and P < 0.001, respectively). On days 14 and 21, the mean VAS score was significantly low in the NPWT group (P < 0.001 and P < 0.001, respectively). The majority of wounds in the NPWT group were sterile on day 21 compared to those in the CD group (P = 0.008). The majority of patients in the NPWT group had excellent patient satisfaction (P < 0.001). The average material cost was significantly higher in the NPWT group (P = 0.001). The mean wound temperature of the affected limb was significantly higher compared to that of the unaffected limb (P < 0.001).
Conclusion:
In terms of early formation of granulation tissue, faster wound size reduction, less discomfort, and patient satisfaction, the study indicated that NPWT appeared to be superior. An initial rise in temperature in a DFU may indicate the presence of a pre-ulcerative lesion.
Keywords: Diabetic Foot Ulcer, negative pressure wound therapy, thermography, Visual Analog Scale
Introduction
Diabetic foot ulcers are one of the most serious consequences of diabetes mellitus, with a lifetime risk of 25%.[1] If infection and sepsis are not treated promptly, amputation of a leg may be required.[2]
Since its beginning, negative pressure wound therapy (NPWT) has been an extensively used treatment method for a variety of clinical purposes. NPWT is also known as vacuum-assisted closure, subatmospheric pressure therapy, and topical negative pressure therapy, among other terms.[3] NPWT was created with the intention of treating chronic wounds. About 2% of the population may acquire a chronic wound during their lifetime, and NPWT has revolutionized the treatment of these wounds.[4] Long-term dehisced wounds, vascular and diabetic ulcers, pressure ulcers, and venous stasis ulcers are among the chronic wounds that can be treated using NPWT.[5,6,7] Argenta and Morykwas investigated the use of foam contact layers in both humans and animals and discovered that using NPWT with a pressure setting of –125 mmHg was likely to shorten healing time, reduce local edema, and manage wound exudates.[8]
NPWT is not a substitute for surgery, but it can help a wound advance to the point where a less-invasive operation is viable.[9,10] NPWT is gradually becoming acknowledged as a tool for achieving a number of therapy goals, which vary depending on the patient and wound characteristics.[11]
Chronic wounds frequently remain in an inflammatory state, preventing them from proliferating. In the presence of defective cellular and systemic host responses, tissue injury, hypoxia, hyperglycemia, and a high bacterial burden maintain a detrimental loop that hinders advancement into the proliferative phase of recovery.[12] As established in numerous studies,[13,14] inflammation is a possible sign in diabetic foot ulcers (DFUs) and can be assessed by taking temperature.
The goal of this prospective study was to compare the effects of NPWT versus conventional dressing (CD) on wound healing in DFU patients in terms of wound temperature, wound size reduction, granulation tissue, pain, wound/blood culture, patient satisfaction, and treatment cost.
Materials and Methods
From July 2018 to December 2019, a study was undertaken on DFU patients who presented to the Surgical outpatient department (OPD) and Wound Clinic at Sir Sunderlal Hospital, Institute of Medical Sciences, Banaras Hindu University, Varanasi. The Institute Ethical Committee approved the study protocol. All patients signed written informed consent. The study included all patients over the age of 18 years. Patients with osteomyelitis, coagulopathy, venous illness, ischemic wounds, peripheral vascular disease, Charcot’s joint, cancer patients, patients on corticosteroids or chemotherapy, pregnant patients, and nursing mothers were excluded.
Patients were randomly assigned into two groups, NPWT or CD, using a computer-generated random number table. The demographics, medical history, clinical examination, and relevant investigations of the patient were documented. All patients had a surgical debridement for necrotic area or slough.
Under all aseptic settings, a foam-based dressing was placed on the wounds of the patients allocated to the NPWT group. To form an airtight seal, the dressing was covered with an adhesive drape. For 6 days, an evacuation tube embedded in foam was linked to vacuum at a subatmospheric (negative) pressure of −125 mmHg. Depending on the wound type, the wall suction pump could be configured to provide different levels of negative pressure (100–250 mmHg) on an intermittent or a continuous basis. The discharge was emptied into a collection canister via the tube. Patients who were treated with CDs got daily wound dressing. The foam-based dressings were changed every 7 days, while the CDs were changed daily.
Wound culture sensitivity, wound size, granulation tissue, and pain evaluation (assessed by Visual Analog Scale [VAS]) were all measured at the start and 3 weeks or until the ulcer was healed. For scoring purposes, only healthy granulation tissue that showed pink was used [Table 1]. Wound culture sensitivity was checked every week to determine infection. In addition, the number of secondary debridements and small amputations was recorded. Re-debridement and re-NPWT were performed if wound healing was insufficient.
Table 1.
Granulation tissue score and patient satisfaction score
| Score | Criteria |
|---|---|
| Granulation tissue | |
| Score 1 | No granulation |
| Score 2 | Granulation tissue covering 25%-74% of the wound |
| Score 3 | Granulation tissue covering 25%-74% of the wound |
| Score 4 | Granulation tissue covering 75%-100% of the wound |
| Patient satisfaction | |
| Excellent | If the wound closed within 3 weeks and only required one antibiotic |
| Very good | If the wound closed within 8 weeks and required two antibiotics |
| Good | If the wound closed during week 3 or amputation of one or more digits was required |
| Unsatisfactory | If the wound did not close within the treatment period or if the patient required major or foot amputation |
The wound margin temperature was measured at four random sites for thermometric evaluation, and the mean was taken as the wound temperature. Normal limb temperature was also measured on the contralateral limb at around the same points for comparison. The receiver operating characteristic (ROC) curve was used to determine the most optimal cut-off value for skin temperature for identifying the temperature difference between the ulcer margin and contralateral healthy skin. Both groups had their patient satisfaction [Table 1] and treatment costs reviewed at the end of treatment.
Data were evaluated using Statistical Package for the Social Sciences (SPSS) 23.0 for windows (IBM Inc., Chicago, USA). Comparison was done between NPWT and CD groups in terms of demographics, wound characteristics, laboratory investigation reports, wound size, granulation tissue, pain, wound culture, patients’ satisfaction, and the cost of treatment. For categorical variables, Chi-square test and Fischer’s exact test were used. For comparing two groups of mean, Student’s t test was used. ROC curve analysis was used to predict ulcer occurrence in diabetic patients, considering the skin temperature in foot ulcer patients and healthy controls.
Results
A total of 63 patients with DFU were enrolled in the study. Out of these, eight patients were excluded because of Doppler evidence of peripheral vascular disease, one patient had varicose veins, and two patients had evidence of osteomyelitis on foot X-ray. Finally, 55 patients were included in the study and were divided into two groups: 23 patients treated with NPWT and 32 patients with CD.
There were 42 (76.36%) males and 13 (23.64%) females among the 55 patients. The average age of the participants was 37.12 ± 7.08 years (range 30–45 years). The average age of patients treated with NPWT was 37.32 ± 6.64 years, compared to 36.74 ± 7.22 years in the CD group. [Table 2] shows the demographics and patient characteristics of both groups.
Table 2.
Patients’ characteristics and demography of both the groups
| NPWT group (n=23) | CD group (n=32) | P | |
|---|---|---|---|
| Age (years) | 37.32±6.84 | 36.74±7.22 | 0.765 |
| Male/female | 16/7 | 26/6 | 0.316 |
| Body mass index (kg/m2) | 23.32±4.58 | 23.57±4.33 | 0.837 |
| Hemoglobin (g/dl) | 10.36±3.47 | 10.87±2.88 | 0.554 |
| Uncontrolled diabetes (HbA1c >7) | 9 (39.1) | 13 (40.6) | 0.911 |
| Current tobacco use and smoking | 18 (78.3) | 27 (84.4) | 0.562 |
| Currently use alcohol | 6 (26.10) | 9 (28.12) | 0.861 |
| Duration of ulcer (months) | 4.88±1.21 | 4.32±1.56 | 0.156 |
| Wagner’s scale | |||
| Grade 2 | 4 (17.4) | 7 (21.9) | 0.681 |
| Grade 3 | 19 (82.6) | 25 (78.1) | |
| Size of wound (cm2) | 20.46±3.45 | 19.87±3.66 | 0.548 |
| Ulcer area (cm2) | 68.44±31.48 | 70.63±30.96 | 0.920 |
| Initial amputation | 9 (39.1) | 15 (46.9) | 0.567 |
| Wound culture | |||
| Polymicrobial | 11 (47.8) | 14 (43.8) | 0.537 |
| Monomicrobial | 12 (52.2) | 18 (56.3) | |
| Sterile | 0 | 0 | |
| Wound temperature (°C) | 32.87±0.99 | 32.55±1.04 | 0.265 |
CD=conventional dressing, NPWT=negative pressure wound therapy
The mean ulcer duration in the NPWT group was 4.88 ± 1.21 months, while it was 4.32 ± 1.56 months in the CD group, which was comparable (P = 0.156). The baseline mean wound size in the NPWT group was 20.46 ± 3.45 cm2, while it was 19.87 ± 3.66 cm2 in the CD group (P = 0.548). Initial amputation was performed in nine (39.1%) patients in the NPWT group and 15 (46.9%) patients in the CD group (P = 0.567).
The baseline wound culture report showed 11 (47.8%) patients had polymicrobial and 12 (52.2%) patients had monomicrobial growth in the NPWT group and 14 (43.8%) patients had polymicrobial flora and 18 (56.3%) patients had monomicrobial growth in the CD group (P = 0.537).
The wound sizes of the two treatment groups were comparable at baseline and on day 7. On day 14 and day 21, the NPWT group had a significantly faster reduction in wound size than the CD group (P < 0.001 and P < 0.001, respectively) [Table 3]. The percentage reduction in wound size from baseline to day 7, day 14, and day 21 was significantly higher in the NPWT group than in the CD group (P = 0.013, P = 0.001, and P = 0.029, respectively) [Table 3]. The two treatment groups had similar granulation tissue scores at the start (P = 0.913). On day 7, day 14, and day 21, the granulation tissue score was significantly higher in the NPWT group than in the CD group (P = 0.001, P = 0.001 and P < 0.001, respectively) [Table 3]. The mean VAS score for pain was comparable between the two treatment groups at baseline and on day 7. On day 14 and day 21, VAS score was significantly lower in the NPWT group than in the CD group (P < 0.001 and P < 0.001, respectively) [Table 3].
Table 3.
Comparison of wound size reduction in NPWT versus conventional dressing
| NPWT group (n=23) | Conventional dressing group (n=32) | P | |
|---|---|---|---|
| Wound size (cm2) | |||
| Baseline | 20.46±3.45 | 19.87±3.66 | 0.548 |
| Day 7 | 17.23±2.98 | 18.63±3.11 | 0.078 |
| Day 14 | 9.67±2.46 | 14.78±2.87 | <0.001 |
| Day 21 | 4.21±1.12 | 10.53±2.21 | <0.001 |
| Percentage (%) decrease in size | |||
| From baseline to day 7 | 15.78±13.62 | 5.63±15.02 | 0.013 |
| From baseline to day 14 | 52.73±28.69 | 25.61±21.58 | 0.001 |
| From baseline to day 21 | 79.42±67.53 | 47.00±39.61 | 0.029 |
| Granulation tissue (cm2) | |||
| Baseline | 1.39±0.49 | 1.40±0.49 | 0.913 |
| Day 7 | 2.17±0.65 | 1.56±0.66 | 0.001 |
| Day 14 | 3.39±0.83 | 2.59±0.75 | 0.001 |
| Day 21 | 4.47±0.73 | 3.43±0.80 | <0.001 |
| VAS score for pain | |||
| Baseline | 8.08±0.84 | 8.06±0.84 | 0.916 |
| Day 7 | 7.73±0.86 | 7.96±0.64 | 0.265 |
| Day 14 | 5.95±1.06 | 7.65±0.78 | <0.001 |
| Day 21 | 4.65±1.15 | 6.75±1.16 | <0.001 |
NPWT=negative pressure wound therapy, VAS=Visual Analog Scale
At the end of treatment, the majority of wounds in the NPWT-treated group were sterile on day 21 compared to the wounds in the CD group (P = 0.008). Only six (18.75%) patients in the CD group had excellent satisfaction, compared to 20 (86.95%) in the NPWT group. In comparison to those in the CD group, the majority of patients in the NPWT group had excellent patient satisfaction (P < 0.001) [Table 4].
Table 4.
Final outcome at the end of treatment (wound culture, patient satisfaction, and cost of materials)
| NPWT group (n=23) | Conventional dressing group (n=32) | P | |
|---|---|---|---|
| Wound culture | 0.008 | ||
| Polymicrobial | 1 (4.35) | 9 (28.12) | |
| Monomicrobial | 2 (8.70) | 8 (25.0) | |
| Sterile | 20 (86.95) | 15 (46.88) | |
| Patient satisfaction | <0.001 | ||
| Excellent | 20 (86.95) | 6 (18.75) | |
| Very good | 3 (13.05) | 9 (28.12) | |
| Good | 0 | 8 (25.0) | |
| Poor | 0 | 6 (18.75) | |
| Not satisfied | 0 | 3 (9.38) | |
| Cost of treatment (rupees) | 25740±4500 | 22560±1320 | 0.001 |
NPWT=negative pressure wound therapy
The average material cost of NPWT-treated patients was 25,740 ± 4500 rupees, compared to 22,560 ± 1320 rupees for CD. The average material cost was significantly higher in the NPWT group than the cost of CD material (P = 0.001). We solely compared the material prices because our center is a government-run tertiary care facility with exceptionally low nursing and hospitalization costs [Table 4].
The mean wound temperature of the affected limb was 32.73°C ± 1.01°C and of the contralateral unaffected limb was 30.83°C ± 1.47°C (P < 0.001) [Table 5]. The mean temperature for the patients in the NPWT group was 32.87°C ± 0.99°C and in the CD group was 32.55°C ± 1.04°C with no significant difference (P = 0.265). The area under the ROC curve was 0.848 for detection of a diabetes-related foot ulcer [Figure 1], when the temperature of ulcer was compared with the same site skin temperature of the opposite limb. The most optimal cut-off skin temperature value to detect a diabetes-related foot ulceration was 31°C. Using this value, sensitivity was 98% and specificity was 51%. Based on this cut-off temperature, wounds in both groups were classified during follow-up [Table 6]. At baseline and on day 7, both NPWT and CD groups had comparable patient distribution according to the cut-off temperature of 31°C. However, on day 14 and day 21, the NPWT group showed a significant percentage of patients having a wound temperature <31°C (P = 0.043 and P < 0.001, respectively), suggesting the healing of ulcer.
Table 5.
Comparison of wound temperature between the affected leg and control leg
| Temperature (°C) Mean±SD | P | |
|---|---|---|
| Affected leg | 32.73±1.01 | <0.001 |
| Control leg | 30.83±1.47 |
SD=standard deviation
Figure 1.
ROC curve analysis was used to predict ulcer occurrence in diabetic patients, considering the skin temperature in foot ulcer and healthy controls. ROC = receiver operating characteristic
Table 6.
Comparison of wound temperature measurement using an infrared camera between the NPWT and conventional groups
| Temperature (°C) | NPWT group (n=23) | Conventional dressing group (n=32) | P |
|---|---|---|---|
| Baseline | 0.999 | ||
| ≤31 | 0 | 1 (3.1) | |
| >31 | 23 (100) | 31 (96.9) | |
| Day 7 | 0.191 | ||
| ≤31 | 4 (17.4) | 2 (6.3) | |
| >31 | 19 (82.6) | 30 (93.8) | |
| Day 14 | 0.043 | ||
| ≤31 | 11 (47.8) | 7 (21.9) | |
| >31 | 12 (52.2) | 25 (78.1) | |
| Day 21 | 0.001 | ||
| ≤31 | 19 (82.6) | 11 (34.4) | |
| >31 | 4 (17.4) | 21 (65.6) |
NPWT=negative pressure wound therapy
Area under the curve
| Area | Cut-off | P | Sensitivity | Specificity |
|---|---|---|---|---|
| 0.848 | 31.00 | <0.001 | 98.0% | 51% |
Discussion
Vascular surgeons are concerned about the treatment of DFUs because of their uncertain healing time.[9] Debridement, infection assessment, and therapy, revascularization if required, and adequate off-loading of the foot are all part of the treatment. Debridement of all infected and necrotic tissues is the mainstay of therapy, with the primary goal being wound closure.[15] The standard treatment strategy has been saline-moistened gauze.[1] Various hydrocolloid wound gels, growth factors, enzymatic debridement agents, hyperbaric oxygen therapy, cultured skin substitutes, and other wound therapies were proposed as a result. All of these medications are costly, and some of them are being used in contexts in which there is little scientific evidence to support their efficacy.[16]
NPWT is presently the therapy of choice for DFUs. NPWT is a noninvasive technique of creating regulated negative pressure. It has been shown to be a safe and effective treatment for complex diabetic foot wounds, with the potential to improve wound healing rates.[17] It alters the internal wound environment, reducing bacterial load, decreasing wound collection, and increasing vascularity within the wound by utilizing the periwound area’s elasticity. Vacuum dressings are well tolerated and are quickly becoming the wound treatment of choice. However, the outcomes of several trials comparing it to conventional wound dressing were mixed.
Wound size was comparable between the two treatment groups at baseline and on day 7. On days 14 and 21, wound size reduction was considerably faster in the NPWT group than in the CD group (P < 0.001 and P < 0.001, respectively). The percentage reduction in wound size from baseline to days 7, 14, and 21 was significantly higher in the NPWT group than in the CD group (P = 0.013, P = 0.001, and P = 0.029, respectively). In their study, Lone et al.[1] found that the majority of wounds in the NPWT group (78.6%) decreased in size, compared to 53.6% in the conventional group. According to McCallon et al.,[18] the wound size in the NPWT group decreased by 28.4%, compared to 9.5% in the control group (saline-moistened gauze dressings). In a systematic review and meta-analysis conducted by Liu et al.,[19] the authors found that NPWT reduces DFUs significantly more than standard dressing. In DFUs treated with NPWT and CD, Nain et al.[20] found that the mean ulcer area was reduced by 16.14 and 5.98 cm2, respectively.
NPWT promotes fibroblast proliferation, macrophage migration, and development of early granulation tissue. NPWT exhibits a significant granulation tissue development effect in the proliferation phase, including blood vessel sprouting.[21] NPWT eliminates invading leukocytes while simultaneously inducing inflammation during the inflammatory phase.[22] The baseline granulation tissue score was comparable in both treatment groups (P = 0.913). On days 7, 14, and 21, the granulation tissue score was significantly higher in the NPWT group than in the CD group (P = 0.001, P = 0.001, and P < 0.001, respectively). This could be attributed to the increased blood flow due to the negative pressure aiding in faster angiogenesis and increased nutrient supply, as well as discharge decreasing at a faster rate, allowing the ulcers to heal faster. By the end of 2 weeks, granulation tissue had appeared in 92.85% of patients with vacuum dressings, compared to 53.57% of patients with traditional dressings, according to Lone et al.[1] At the end of 2 weeks, Mogal et al.[23] observed that the conventional group had a 50.9% improvement in granulation tissue, whereas the NPWT group had an 84.9% improvement. Vacuum dressings increased the weight of granulation and wounds healed faster with them than with saline gauze dressings, according to Armstrong et al.[17]
In DFUs, only a few studies[24,25] examined pain between NPWT and standard dressing. Negative suction is believed to be the source of pain in NPWT. The granulation tissue that forms into the pores of the foam is disrupted during the dressing change, which might result in pain. In this study, week 3 was chosen since the median duration to healing in the NPWT and traditional dressing groups was 21 and 36 days, respectively, which is around 3 weeks. All wounds were infected and coated in slough and necrotic tissue at the time of the initial presentation, necessitating considerable debridement and causing increased pain in all patients. The mean VAS score for pain between the two treatment groups was comparable at baseline and on day 7 in our study. On days 14 and 21, the mean VAS score was significantly lower in the NPWT group than in the CD group (P < 0.001 and P < 0.001, respectively). This could be attributed to the fact that the NPWT group required fewer dressings. In a research by James et al.,[26] the median VAS score was comparable between the NPWT and CD groups after 1 week of treatment (P = 0.271), but significantly lower in the NPWT group after 3 weeks of treatment (P = 0.004). According to Nather et al.,[25] patients in the NPWT group required half the number of dressings as those in the control group, because dressing was done once in every 2 days in the NPWT group.
Infection is more often the result of foot ulceration than the cause, yet it can cause significant damage and delay in healing. Bacteria are everywhere, and determining their impact on healing is tough.[27] The wound healing effects of NPWT may be due to an increase in bacterial clearance. Large, extensive wound surfaces received a sterile, more regulated resting environment because to NPWT.[28] On day 21, the majority of wounds in the NPWT-treated group were sterile when compared to the CD group (86.95% vs. 46.88%, P = 0.008). Our findings are in line with those of Lone et al.,[1] who observed that patients in the NPWT group had lower rates of culture positivity than those in the CD group.
Patients treated with NPWT were more satisfied (excellent) than those treated with CDs (P < 0.001) in our study owing to the fact that NPWT-treated patients did not require a daily change of dressing, making them feel less uncomfortable, experiencing fewer treatment-related complications, having a better outcome, and having a better quality of life. Our findings are in line with those of a number of previous studies.[1,29,30]
The average material costs of NPWT-treated patients (25,740 ± 4500 rupees) were substantially higher than those of patients treated with CD (22,560 ± 1320 rupees) in the current study (P = 0.001). Nursing and hospitalization costs are quite low in government hospitals like ours (approximately 1000 rupees per patient). Only the cost of treatment materials was compared in our study. Mouës et al.[31] observed that wounds treated with NPWT therapy had significantly higher mean material costs than the wounds treated with conventional therapy, but the significantly lower mean nursing costs and lower hospitalization costs in the NPWT therapy group were due to an average shorter time until they were ready for surgical closure. Total expenses per patient did not change significantly between the two therapies. Apelqvist et al.[32] conducted a randomized controlled trial to quantify the utilization of resources and direct costs of care for diabetic patients with post-amputation wounds who were treated with NPWT versus moist wound management. They observed that the NPWT group used fewer resources and spent less money on care.
A sudden rise in plantar temperature is a warning indicator of impending pre-ulcer inflammation, necessitating immediate medical attention.[33] It has been proven that an increase in temperature can occur up to a week before a foot ulcer develops.[34,35] The temperature distribution in the plantar foot of a control person is with a bilateral butterfly pattern, according to Chan et al.[36] Sun et al.[35] found that in the normal and diabetic populations, the temperature of the medial plantar arch was the greatest and that of the lesser toes was the lowest. The poor thermoregulation in diabetic feet is the cause of the fluctuating skin temperature.[37] Increased arteriovenous (A–V) shunt flow causes the temperature to rise in neuropathic diabetic foot.[35]
In our study, the mean wound temperature of the affected limb was significantly higher than that of the contralateral unaffected limb (P < 0.001), but there was no significant difference in the mean temperature between the patients in the NPWT and CD groups (P = 0.265).
When the temperature of the ulcer was compared to the same site skin temperature of the opposite limb, the area under the ROC curve for detecting a diabetes-related foot ulcer was 0.848. The best skin temperature cut-off value for detecting a diabetes-related foot ulcer was 31°C, which had a sensitivity of 98% and a specificity of 51%. In the follow-up, wounds in both groups were categorized based on this cut-off temperature. According to the cut-off temperature of 31°C, both groups exhibited comparable patient distribution at baseline and on day 7. However, on days 14 and 21, the NPWT group had a significantly higher percentage of patients with a wound temperature of 31°C (47.8% vs. 21.9%, P = 0.043 and 82.6% vs. 34.4%, P < 0.001, respectively), indicating ulcer healing.
Thermography can be utilized to assess a variety of skin-related disorders, according to these findings. When compared to many other medical imaging modalities, thermography is a simple, noninvasive, and inexpensive procedure. However, before they can be widely used in medical diagnostics, the analytical methods will need to be refined further. On chronic DFUs, there have been no thermographic studies. As a result, more research into the thermographic patterns of diabetic ulcer patients, both acute and chronic, is needed.
Conclusion
NPWT appeared to be superior to CD in treatment of DFU, providing a higher quality of life due to the following reasons:
Early formation of granulation tissue
Faster wound size reduction
Less discomfort
No need to change daily dressing
Less or no pain making the patient feel more comfortable and satisfied
Greater per dressing cost, but substantially lower overall cost
An initial rise in temperature in a DFU may indicate the presence of a pre-ulcerative lesion.
Financial support and sponsorship
Nil.
Conflicts of interest
There are no conflicts of interest.
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