Ilkka Kaartinen

A review of indocyanine green fluorescent imaging in surgery

The purpose of this paper is to give an overview of the recent surgical intraoperational applications of indocyanine green fluorescence imaging methods, the basics of the technology, and instrumentation used. Well over 200 papers describing this technique in clinical setting are reviewed. In addition to the surgical applications, other recent medical applications of ICG are briefly examined.

Human skin transcriptome during superficial cutaneous wound healing.

Healing of the epidermis is a crucial process for maintaining the skins defense integrity and its resistance to environmental threats. Compromised wound healing renders the individual readily vulnerable to infections and loss of body homeostasis. To clarify the human response of reepithelialization, we biopsied split‐thickness skin graft donor site wounds immediately before and after harvesting, as well as during the healing process 3 and 7 days thereafter. In all, 25 biopsies from eight patients qualified for the study. All samples were analyzed by genome‐wide microarrays. Here, we identified the genes associated with normal skin reepithelialization over time and organized them by similarities according to their induction or suppression patterns during wound healing. Our results provide the first elaborate insight into the transcriptome during normal human epidermal wound healing. The data not only reveal novel genes associated with epidermal wound healing but also provide a fundamental basis for the translational interpretation of data acquired from experimental models.

Objective scar assessment—A new method using standardized digital imaging and spectral modelling

INTRODUCTION Quantitative assessment of scars is needed in clinical practice and in scientific studies. To date, there have been no entirely objective methods available for these purposes. We introduce a new method developed for scar assessment combining standardized digital imaging (SDI) and spectral modelling (SpM). With this method, the estimated concentration changes (ECCs) of haemoglobin and melanin in the scar can be determined quantitatively. PATIENT AND METHODS In the current study, 22 skin graft donor site (SGDS) wounds were treated with two alternative dressing materials, Suprathel® and Mepilex Transfer®, side by side on the same wound. The SGSD scars were assessed using SDI and SpM. The scars were given subjective ratings by three surgeons using the POSAS and the Vancouver Scar Scale (VSS). The correlations between the ECCs of melanin and haemoglobin and the corresponding subjective ratings were calculated as well as the Intraclass Correlation Coefficient (ICC) of the subjective ratings. RESULTS There was a statistically significant correlation between the ECCs of melanin and haemoglobin and the subjective ratings. A single observer could reliably assess pigmentation with the POSAS scale (ICC = 0.75) but not vascularity (ICC = 0.51). The reliability ratings of the VSS were unacceptably low. CONCLUSIONS The ECC values of haemoglobin and melanin give accurate documentation of the scar status. The results also show that the subjective ratings in this study were unreliable especially when interfering pigmentation and increased vascularity were both present at the same time.

How to assess scar hypertrophy—a comparison of subjective scales and Spectrocutometry: A new objective method

Scar hypertrophy is a significant clinical problem involving both linear scars from elective surgery and scars caused by trauma or burns. The treatment of hypertrophic scars is often time consuming, and patients may need to be followed up for months or even years. The methods for reliable quantification of scar hypertrophy are at present unsatisfying. We have developed a new, objective method, Spectrocutometry, for documentation and quantification of scar hypertrophy. The instrument is based on standardized digital imaging and spectral modeling and calculates the estimated concentration change of hemoglobin and melanin from the entire scar and also provides standardized images for documentation. Three plastic surgeons have assessed 37 scars from melanoma surgery using Spectrocutometry, the Vancouver scar scale, and the patient and observer scar assessment scale. The intraclass correlation coefficient for the Vancouver scar scale and the patient and observer scar assessment scale was lower than required for reliable assessment (r=0.66 and 0.60, respectively). The intraclass correlation coefficient for Spectrocutometry was high (r=0.89 and 0.88). A Bayesian network analysis revealed a strong dependency between the estimated concentration change of hemoglobin and scar pain. Spectrocutometry is a feasible method for measuring scar hypertrophy. It is shown to be more reliable than subjective rating in assessing linear surgical scars.

The dermis graft: another autologous option for acute burn wound coverage.

BACKGROUND Split-thickness skin autografts are the gold-standard in providing permanent acute wound closure in major burns. Split-thickness dermal grafts harvested from the same donor site may provide an additional autologous option for permanent acute coverage and increase the number of potential autologous donor sites. MATERIALS AND METHODS We performed 16 dermis grafts (DG) harvested from the skin of the back in 9 consecutive burn patients. A control donor site consisted of an area of adjacent back skin from which a standard split-thickness skin graft was harvested. The mean age was 63 years (range 23-79 years). The mean initial burn size was 24% TBSA (range 2-40% TBSA). The size of the 16 DG recipient wound beds ranged from 20 to 180 cm2, with mean and median sizes of 62 and 45 cm2, respectively. RESULTS Dermis graft take was complete in 15/16 cases. All grafts recorded >90% epithelialisation by 4 weeks. There was no significant difference in dermis graft and control donor site healing times (p value 0.05). CONCLUSION Dermis grafts can provide an additional autologous option for permanent coverage in acute major burn wounds without increasing donor site size or morbidity.

Comparison of Suprathel® and allograft skin in the treatment of a severe case of toxic epidermal necrolysis

Toxic epidermal necrolysis (TEN) is a rare potentially lifethreatening drug-induced skin disorder resulting in extensive mucocutaneous exfoliation and systemic involvement. TEN is now generally considered to result from a disregulated immune reaction against epithelial cells. TEN was first described by Alan Lyell [1] and is therefore commonly referred to as Lyell’s disease or syndrome. It is closely related to Stevens–Johnson syndrome (SJS) and both conditions are considered to be caused by the same disease process. SJS is often defined by less than 10% epidermal loss and TEN more than 30% loss with those in between classified as SJS-TEN. Clinically they present with an acute macular erythematous rash with bullae which can rapidly progress to extensive areas of epidermal separation and shedding. A positive Nikolsky’s sign (slight rubbing of the skin resulting in exfoliation of the outermost layer) is characteristic [2]. The SCORTEN severity of illness scoring system helps to predict mortality in TEN patients [3]. Due to often extensive areas of epidermal involvement with resultant water, electrolyte and protein losses it is generally agreed that these patients should be admitted early to a Burn Unit [1]. At present there are no standard management guidelines but treatment should be multidisciplinary with prompt diagnosis, withdrawal of the suspected drug, supportive care and wound management. Many specific pharmacological therapies are cited in the literature but a general consensus and evidence base is lacking. However topical wound care is an integral part of the overall management of this condition. The areas of epidermal loss can be compared to the wound of a partial-thickness burn and thus many different wound dressings are available. At present there is no general agreement as to what is the most efficacious and appropriate wound care material. Suprathel (PMI Polymedics Innovations GmbH, Germany) is a recently introduced epidermal substitute. It is composed of a synthetic co-polymer of polylactide, trimethylene carbonate, and e-caprolactone and has been used in partial-thickness burns as well as in split-thickness skin graft donor sites. It is reported to reduce pain in both burn and donor site wounds and also to reduce exudation of donor sites compared to a conventional open method [4,5]. There are two reports of the use of Suprathel in Staphylococcal scalded skin syndrome [6] and TEN in a young infant [7]. Allograft (cadaveric) skin however is well recognised for its use in TEN as well as its versatility in burn patients in general [8–10]. We report our experience in the use of Suprathel and allograft skin in a severe case of TEN.

Improved skin wound epithelialization by topical delivery of soluble factors from fibroblast aggregates

INTRODUCTION Timely coverage of an excised burn wound with a split-thickness skin graft, and efficient epithelialization at the donor site wound are key components in the treatment of burn patients. Prompt healing is dependent on paracrine support from underlying dermal connective tissue fibroblasts. STUDY AIM Using the skin graft donor site in pig as a model for epithelialization, our aim was to evaluate if dermal signals, derived from cultured dermal fibroblast aggregates (Finectra), can promote epidermal regeneration. MATERIALS AND METHODS Partial-thickness skin wounds were made with a dermatome on the backs of three domestic pigs. After randomization, topical treatment was initiated by application of Finectra (n=6) or factors from standard fibroblast monolayer cultures (n=6) trapped in a slow-clotting fibrin matrix. Saline was applied to contralateral wounds to serve as corresponding untreated controls (n=12). After 3 days, full-thickness skin samples representing the whole wound area were obtained. Histological sections of these samples were analyzed for epithelialization, cell migration from lateral wound edges and hair follicles, as well as for formation of granulation tissue. RESULTS In response to topical delivery of Finectra, a significant acceleration of epithelialization (p<0.001) across the wound surface as well as from the wound edges was evident. Marked increase in thickness of granulation tissue (p<0.001) was noted in wounds treated with Finectra. Epihelialization originated from adnexal structures in which epithelial islets showed positive staining for cytokeratin-14 and PCNA. CONCLUSION These data show that the fibroblast aggregate-derived paracrine mediators, Finectra, stimulate epidermal regeneration in vivo.

The colour of blood in skin: a comparison of Allen's test and photonics simulations.

Background: The colour of the skin reflects many physiological and pathological states of an individual. Usually, the skin colour is examined by the bare eye alone. Several scaling systems have been developed to quantify the sensory evaluation of skin colour. In this work, the reflectance of the skin is measured directly using an objective instrument. Haemoglobin inside the dermal circulation is one of the key factors of skin colour and it also has a major role in the appearance of many skin lesions and scars. To quantitatively measure and analyse such conditions, the relation between the skin colour and the haemoglobin concentration in the skin needs to be resolved.

Long-Term Results of Intralesional Triamcinolone Acetonide Injections inKeloid Treatment

Background: Intralesional triamcinolone acetonide (TAC) injections are often used as the first alternative for treating keloid scarring. The long-term outcome of this treatment is unclear. Also, undesirable local side effects have been recognized in clinical work and literature but they have been labelled as harmless and rare. Methods: We documented the long-term outcome of intralesional TAC injections in the treatment of keloid scars in Tampere University Hospital. The main objectives were to investigate the remission rate and the occurrence of local side effects. We assessed 105 patients (46 women, 59 men) with 138 TAC treated keloid scars at the outpatient clinic. The keloids were photographed and assessed with Patient and Observer Scar Assessment Scale (POSAS). Results: Of the 138 keloids, 90 (65%) were clinically in remission. Local side effects, including atrophy of the skin or the subdermal fat, telangiectasia and cortisone traces, occurred in 55% of the cases. The number of injections did not correlate with remission rate or the occurrence of local side effect. ROC curve analysis showed that surface area >620 mm2 was a prognostic factor for not responding to TAC treatment. Conclusion: According to this study, intralesional TAC injections seem to be effective in the treatment of small keloids but not in larger than 620 mm2. Local side effects were more frequent than previously reported and occurred even after just 1 injection. The side effects seem to be permanent in nature.

Modified approach for endoscopic harvest of the latissimus dorsi free flap with CO2 insufflation and standard laparoscopic equipment

The latissimus dorsi (LD) muscle flap is frequently used for free tissue transfer to reconstruct large defects of the extremities. As a free flap, the LD also can be harvested as a muscle‐sparing flap (MS‐LD), preserving the innervation and insertion of the remaining muscle. Conventional harvesting of the LD flap, however, results in a long scar on the lateral back. Harvesting using an endoscopic approach minimizes donor site morbidity. We present our modified endoscopic technique with CO2 insufflation and standard endoscopic instruments for harvesting the LD or MS‐LD muscle flap.