Potential markers of healing from near infrared spectroscopy imaging of venous leg ulcer. A randomized controlled clinical trial comparing conventional with hyperbaric oxygen treatment

Breath-Holding as a Stimulus to Assess Peripheral Oxygenation Flow Using Near-Infrared Spectroscopic Imaging

A mammalian breath-hold (BH) mechanism can induce vasoconstriction in the limbs, altering blood flow and oxygenation flow changes in a wound site. Our objective was to utilize a BH paradigm as a stimulus to induce peripheral tissue oxygenation changes via studies on control and diabetic foot ulcer (DFU) subjects. Subjects were imaged under a breath-hold paradigm (including 20 s BH) using a non-contact spatio-temporal-based NIRS device. Oxygenated flow changes were similar between darker and lighter skin colors but differed between wound site and normal background tissues. Thus, the ability of peripheral vasculature to response to oxygenation demand can be assessed in DFUs.

Effects of Oxygen Therapy on Patients with a Chronic Wound: A Systematic Review and Meta-analysis

OBJECTIVE

To synthesize the effects of oxygen-based therapy on patients with a chronic wound.

DATA SOURCES

The authors searched PubMed, EMBASE, and Cochrane Central Register of Controlled Trials for relevant randomized controlled trials from database inception. Investigators measured risk of bias using the Cochrane Collaboration's Risk of Bias tool.

STUDY SELECTION

The included randomized controlled trials focused on the effects (short- or long-term wound healing, amputation rate, percentage of reduction in ulcer size, and poststudy transcutaneous oxygen measurement [TcPO2]) of oxygen-based therapy (including hyperbaric oxygen therapy, topical oxygen therapy, and continuous diffusion of oxygen) on patients with a chronic wound.

DATA EXTRACTION

Researchers extracted information regarding participant characteristics and primary and secondary outcomes from the included studies.

DATA SYNTHESIS

Pooled effects of 31 included studies showed that patients treated with oxygen had better short-term wound healing (risk ratio [RR], 1.544; 95% CI, 1.199 to 1.987), a higher percentage reduction in the ulcer area (standardized mean difference [SMD], 0.999; 95% CI, 0.439 to 1. 599), lower amputation rates (RR, 0.529; 95% CI, 0.325 to 0.862), shorter wound healing time (SMD, -0.705; 95% CI, -0.908 to -0.501), and higher poststudy TcPO2 (SMD, 2.128; 95% CI, 0.978 to 3.278) than those in the control group. For long-term wound healing, there was no statistically significant difference (RR, 1.227; 95% CI, 0.976 to 1.542).

CONCLUSIONS

Oxygen-based therapy improves short-term parameters of wound healing in patients with chronic wounds.

Development of a Tissue Oxygenation Flow-Based Index Toward Discerning the Healing Status in Diabetic Foot Ulcers

Objective: The objective of this study is to characterize breath-hold (BH)-induced oxygenation changes in diabetic foot ulcers (DFUs) and develop an oxygenation flow index (OFI) to discern nonhealing from healing DFUs. Approach: The imaging approach utilizes an innovative BH stimulus that induces vasoconstriction and measures for altering oxygenation flow in and around the tissues of DFUs and controls. The modified Beer-Lambert law was utilized to calculate hemoglobin-based spatiotemporal oxygenation maps in terms of oxygen saturation. Results: We found controls had synchronous BH-induced oxygenation changes across the dorsal (OFI: 29.0%) and plantar (OFI: 57.6%) aspects of the foot. Nonhealing DFUs, however, had less synchronous BH-induced oxygenation changes (OFI <28%). In addition, two complicated healing DFU cases, or cases with underlying issues or poor long-term healing outcomes, were observed to have OFIs <28%. Innovation: An OFI was developed to differentiate nonhealing DFUs from healing DFUs using a single, noncontact, near-infrared optical scanner for spatiotemporal oxygenation monitoring. The OFI has potential to provide immediate feedback on the microcirculation in DFUs, through hemoglobin-based oxygenation parameters. Conclusion: A preliminary threshold (OFI <28%) could differentiate nonhealing and complicated DFUs from healing DFUs. The overall oxygenation flow pattern was less synchronous (or the OFI value reduced) in the nonwound areas of the feet that were nonhealing. In other words, the reduced OFI value (<28%) in the entire foot, excluding the wound region is a possible indicator that the wound may not heal.

Effect of hyperbaric oxygen therapy on the patients with venous leg ulcer: A systematic review and meta-analysis

This systematic review and meta-analysis aim to explore the adjuvant effect of hyperbaric oxygen therapy (HBOT) in patients with venous leg ulcer (VLU) undergoing surgeries and non-surgeries. Literatures were searched from Web of Science, Cochrane Library, Embase, Pubmed, Wan fang, China National Knowledge Infrastructure (CNKI), and VIP from inception to November 15, 2022. The risk ratio (RR) and weighted mean difference (WMD) were used as effect size for categorical variables and continuous variables, respectively, with 95% confidence interval (95%CI). The heterogeneity was assessed using Q-test and quantified as I2. Sensitivity analysis was performed for all outcomes. A total of 11 studies were finally included in this study, with a total of 617 patients (313 in the HBOT group and 304 in the control group). Results showed that HBOT in combination with surgeries was associated with shorter ulcer healing time (WMD: -13.76, 95%CI: -20.42 to -7.10), lower VAS score (WMD: -0.95, 95% CI: -1.83 to -0.07), and smaller ulcer area (WMD: -2.64, 95%CI: -3.86 to -1.42). HBOT in combination with non-surgeries was associated with higher ulcer PAR (WMD: 20.82, 95%CI: 5.86 to 35.79), but no statistical significance was found in the improvement of ulcer area (WMD: 0.79, 95% CI: -1.54 to 3.12). Our results indicating that HBOT had a good adjuvant effect in surgeries to treat VLU, and its effect in non-surgeries needed further studies.

Chronic Venous Insufficiency With Emphasis on the Geriatric Population

The underpinning of Chronic Venous Insufficiency (CVI) is valvular dysfunction, which manifests on a spectrum depending on the severity of insufficiency and duration of the disease. The mainstay of treatment relies on compression therapy of a proper type and intensity. In older adults, special consideration must be taken during the patient encounter to account for age-related factors. This review discusses the clinical presentation, diagnosis, and mimicking of CVI, focusing mainly on older adults. The epidemiology, risk factors, disease burden, and grave complications -- such as thrombosis and ulceration, are reviewed. The physiological impacts of CVI are described, providing the background for treatment strategies, including non-invasive, medical, and surgical therapies. The findings show advanced age to be an important risk factor contributing to CVI and that other age-related factors add to the risk of severe complications. Clinical assessments combined with objective measurements that assess localized skin water using tissue dielectric constant values or whole limb assessments may aid in the differential diagnosis. Furthermore, understanding the mechanism of action of compression therapy, the mainstay of CVI treatment, and its physiological impacts, allows for its informed use in geriatric patients with increased risks of potential compression-related side effects.

Hyperbaric Oxygen as an Adjunct in the Treatment of Venous Ulcers: A Systematic Review

BACKGROUND

The use of Hyperbaric Oxygen Therapy (HBOT) in diabetic wounds has been studied extensively. Even though venous insufficiency is the most common cause of lower limb ulceration, there is comparatively little evidence regarding the use of HBOT for Venous Leg Ulcers (VLU). We performed a systematic-review to evaluate and synthesise available evidence, to evaluate whether patients with VLU, when treated with HBOT, had greater rates of (i) complete VLU healing or (ii) reduction in VLU area, than controls.

METHODS

In keeping with PRISMA guidelines, database searches of PubMed, Scopus and Embase was performed. After removal of duplicates, titles were screened for relevance by two authors, then abstracts, and in turn full text manuscripts. Data were extracted from relevant sources including one published abstract. Included studies were assessed for risk of bias using the Risk of Bias 2 (RoB-2) and Risk Of Bias In Nonrandomized Studies (ROBINS-I) tools.

RESULTS

Six studies were included. There was significant heterogeneity across the studies, with no standard control intervention, method of outcome reporting, or duration of follow up. Two studies reported 12 week follow up results and pooled analysis of complete ulcer healing showed no statistically significant difference between HBOT and controls for the outcome of complete ulcer healing OR 1.54 (95%CI = .50-4.75) P = .4478. A similar non-signifiacnt result was seen in four studies reporting 5-6 week follow up; OR 5.39 (95%CI = .57-259.57) P = .1136. Change in VLU area was reported in all studies, and pooled standardised mean difference was 1.70 (95%CI = .60 to 2.79) P = .0024, indicating a statistically significant benefit of HBOT in reducing ulcer area.

CONCLUSION

Existing evidence suggests that HBOT does not significantly affect complete healing of VLU. There is a statistically significant benefit in terms of reducing ulcer size, though in the absence of ulcer healing the clinical significance of this is not established. Current evidence does not justify widespread use of HBOT for VLU.

Resistant Chronic Venous Leg Ulcers: Effect of Adjuvant Systemic Hyperbaric Oxygen Therapy Versus Venous Intervention Alone

The aim of this study was to assess the adjuvant efficacy of adding systemic hyperbaric oxygen therapy (HBOT) to definitive venous intervention for healing of resistant chronic venous leg ulcers (VLUs). From 97 chronic VLUs, 63 were subjected to a pre-study standard wound care. Thirty three ulcers failed to achieve 50% size reduction, after the 4-weeks standard care, and were allocated to be treated with: HBOT plus venous intervention (n = 17), or venous intervention alone (n = 16). Primary outcomes were the change in ulcer area, complete healing frequency and time, as well as ulcer recurrence. There was a history of recurrent ulcer (82.3% vs. 69%) in HBOT versus venous intervention groups, respectively. The comparison between both groups with regard to area change showed non-significant difference after 3 months of therapy, while there was a significant difference at 6 and 12 months. A significant positive correlation was found between the HBO sessions numbers (20-40) and the rate of ulcer size reduction. Ulcer complete closure after 3 months was observed in (41.7%) of HBOT group, versus (23%) in venous intervention group; (p = 0.33). After 12 months, complete closure was observed in (83.3%) of HBOT group, versus (53.8%) in venous intervention group; (p = 0.02). The mean time of complete closure was significantly shorter in HBOT group, (p = 0.001). HBOT may be effective as adjuvant to venous intervention in treatment of chronic resistant VLUs, it should be reserved for persistent ulcer. Randomized controlled trials with larger numbers is still needed to elucidate its exact role and specific indications.

[Modern concept about trophic venous ulcers]

Venous trophic ulcer is a common complication of chronic venous diseases that have a negative impact on the quality of life and result negative socio-economic consequences. There are three main theories of development of venous trophic ulcers. The criterion is visible trophic changes of skin (CEAP class C4). If correction of etiological factor of ulcer is impossible, local management is preferred. There are various wound coverings which can be used for the treatment of trophic ulcers. However, data on their effectiveness are sometimes unavailable. Therefore, it is necessary to systematize knowledge about modern measures and methods of exposure to trophic ulcers. The authors also discuss current understanding of pathophysiology, symptoms and diagnosis of venous trophic ulcers.

Oxygenation therapies for improved wound healing: Current trends and technologies

Degree of oxygenation is one of the important parameters governing various processes, including cell proliferation, angiogenesis, extracellular matrix production, and even combating the microbial burden at the wound site, all...

Hyperbaric Oxygen Therapy Is an Effective Adjunctive Therapy to Manage Treatment-Resistant Venous Leg Ulcers

We report five cases of venous leg ulcers (VLU) that were resistant to conservative therapy for 22–119 months and were eventually healed via hyperbaric oxygen therapy (HBOT). In one patient, VLU recurred four times and was managed using HBOT, each time. The VLU sizes ranged from 18 to 68 cm² before HBOT. HBOT was administered at 2.0 atmospheres absolute with 100% oxygen for 60 min per session, five sessions a week during hospitalization. All VLUs healed after 17–66 sessions of HBOT.

Effectiveness of Blue light photobiomodulation therapy in the treatment of chronic wounds. Results of the Blue Light for Ulcer Reduction (B.L.U.R.) Study

BACKGROUND

Lower limb ulcers not responding to standard treatments after 8 weeks are defined as chronic wounds, and they are a significant medical problem. Blue light (410-430 nm) proved to be effective in treating wounds, but there is a lack of data on chronic wounds in clinical practice. The study's purpose was to determine if Blue Light photobiomodulation with EmoLED medical device in addition to Standard of Care is more effective compared to Standard of care alone in promoting re-epithelialization of chronicwounds of lower limbs in 10 weeks.

METHODS

90 patients affected by multiple or large area ulcers were enrolled. To minimize all variabilities, each patient has been used as control of himself. Primary endpoint was the comparison of the re-epithelialization rate expressed as a percentage of the difference between the initial and final area. Secondary endpoints were: treatment safety, pain reduction, wound area reduction trend over time, healing rate.

RESULTS

At week 10, the wounds treated with EmoLED in addition to Standard Care showed a smaller residual wound area compared to the wounds treated with Standard of Care alone: 42.1% vs 63.4% (p=0.029). The difference is particularly evident in venous leg ulcers, 33.3% vs 60.1% (p=0.007). 17 treated wounds and 12 controls showed complete healing at week 10. Patients showed a significant reduction in pain (p = 2*10-7).

CONCLUSIONS

Blue Light treatment in addition to Standard of Care accelerates consistently the re-epithelialization rate of chronic wounds, especially venous leg ulcers and increases the chances of total wound healing in 10 weeks.

Hyperbaric Oxygen Therapy for Venous Leg Ulcers: A 6 Year Retrospective Study of Results of a Single Center

Background: Venous leg ulcers (VLUs) are common and have a large impact on healthcare budgets worldwide. Hyperbaric oxygen therapy (HBOT) may improve healing of these ulcers. Methods: Retrospective, single-center cohort study between 2013 and 2019. All patients with a VLU from an outpatient clinic providing HBOT and wound care were included. The primary outcome measure was wound healing, determined at discharge from the center. Other outcome measures were improvement in patient related outcome measures (PROMs), as assessed by the EQ-5D-3L questionnaire and including quality of life (QoL) and pain score. Results: Fifty patients were included, 53% female, with a mean age of 73.4 (±12.2). Most wounds (83%) had existed longer than 3 months before starting treatment. Patients received an average of 43 (±20) sessions of HBOT. After treatment, 37 patients (63%) achieved complete or near-complete wound healing. Wound size decreased from a median of 14 cm² [interquartile range (IQR) 32 cm²] to 0.5 cm² (IQR 5.3 cm²), a median decrease of 7.5 (IQR 16.2 cm²) in cm² (94%). Patients mostly reported improvement for all health aspects on the questionnaire. Pain score decreased from 5.7 (±2.5) to 2.1 (±2.2) (p < 0.0001) and health score increased from 57.2 (±15.6) to 69.9 (±18.9) (p = 0.02). Conclusions: Patients with non-healing VLUs may benefit from HBOT to achieve complete or substantial wound healing. We recommend a well-designed randomized clinical trial with a number of patients allowing enough statistical power, and of a reasonable duration, to establish the potential of additional HBOT on hard-to-heal venous ulcers.

The Core of Medical Imaging: State of the Art and Perspectives on the Detectors

In this review, the roles of detectors in various medical imaging techniques were described. Ultrasound, optical (near-infrared spectroscopy and optical coherence tomography) and thermal imaging, magnetic resonance imaging, computed tomography, single-photon emission tomography, positron emission tomography were the imaging modalities considered. For each methodology, the state of the art of detectors mainly used in the systems was described, emphasizing new technologies applied.

Eliminating non-healing wounds: a review

Non-healing cutaneous wounds, including pressure, diabetic and venous ulcers, are wounds where the skin and underlying tissues die due to ischemia, infection, metabolic conditions, immunosuppression or radiation. Some can be eliminated with relatively straightforward techniques, although they may continue to grow in diameter and depth, becoming increasingly painful and never heal. Others respond more slowly or poorly to treatment, while others are recalcitrant to treatments. This review examines the etiology of non-healing wounds and different wound management treatments. In addition, it examines the efficacy of platelet-rich plasma in promoting wound healing and its potential mechanisms of action. It is concluded that platelet-rich plasma alone, but more effectively when combined with another technique(s), has the greatest potential for promoting complete wound healing. However, further studies are required to determine whether the efficacy of wound healing induced by each of these techniques is enhanced by applying the techniques simultaneously.