Candida Antigen Titer Elevation and Mortality in Burn Patients.

BACKGROUND: Mortality in burn patients has several contributing factors as sex, age, degree of burns, or inhalation injuries. Usefulness of Candida antigen (CAG) titer is still being under debate to predict mortality. This study assessed correlation between CAG titer and mortality in burn patients. METHODS: From 1988 to 2011, 877 burn intensive care patients were evaluated for age, sex, total burn surface area (TBSA), multi organ failure (MOF), burn depth, escharotomy, fasciotomy, antibiotic use, co-morbidities, CAG titer and intubation. RESULTS: From 870 admitted patients, 190 patients were not enrolled. Increasing age was correlated with a higher mortality. The abbreviated burn severity index (ABSI) score of the deceased was 4 points and the TBSA was 20% higher than the survivors. The correlation for age, intubation, TBSA, inhalation injury, MOF, CAG titer, antibiotic use and escharotomy was significant. An increasing mortality was noted with antibiotic use and a CAG titer of 1:8 and higher. CAG titer of 1:8 and higher had a sensitivity of 51.1% and specificity of 86.3% for mortality. Multivariate analysis confirmed high influence of older age, MOF, comorbidities, antibiotic use and CAG titer of 1:8 and higher on mortality. There was a significant correlation for sex, younger age and CAG titer. CONCLUSION: CAG titers of 1:8 and higher might warrant beginning of antimycotic treatment in elderly patients with high TBSA to avoid increase in mortality.

Soft Tissue Mandibula and Tongue Reconstruction Using A Suprafascial, Folded, Deepithelialized Antero-Lateral Thigh Perforator Free Flap.

Head and neck squamous cell carcinoma (HNSCC) is the most frequent carcinoma of the head and neck region. For coverage of an entire resected mandible with floor of the mouth, 3/4 of the tongue and soft tissue of cheeks and neck bony reconstruction of the mandible and soft tissue reconstruction of tongue, cheeks and a neck large flap are needed. A patient with a superinfected T4 HNSCC was presented to our outpatient clinic. Complete resection of the mandible, bilateral neck dissection and 3/4 resection of the tongue were performed. A complex reconstruction using two free flaps was not feasable, so a large, folded, suprafascial Antero Lateral Thigh Perforator (ALTP) flap for immediate soft tissue reconstruction was used. Because of the anatomy, no reconstruction plate was inserted. On postop day 11, an understandable speaking was possible using a speach canula. Swallowing was possible without regurgitation. Eight months postoperatively, the patients mimic and closure of the mouth were satisfactory. The flap was viable throughout the entire time. It was shown that the suprafascial ALTP flap was a versatile part in the armamentarium for complex mandible soft tissue reconstruction.

Degloving Injuries of Upper Extremity: A Strategy with Full Thickness Skin Mesh.

Degloving injuries of the upper extremity during work are rare nowadays, because of effective worker protection devices. However, these devastating injuries still occur today during motor vehicle car accidents and surgeons have to be aware of the possibilities of wound coverage for these large, contaminated wounds. We present two cases of degloving injuries of the hand and entire forearm using degloved skin as meshed full thickness skin graft to cover the entire wound. Two patients were admitted to our hospital, presenting large degloving injuries of the entire forearm and hands. Both patients sustained their injuries by being dragged by moving trains and presented additional fractures of the metacarpal bones and in both cases the little finger had to be amputated. The degloved skin was cleansed and meshed as a full thickness skin graft 1:3, using a Brennen Mesher. In both patients, complete wound coverage was achieved using the degloved skin as meshed full thickness skin graft. Attachment to the wound was achieved by vacuum closure device, however, ninety percent of the graft did attach. In both cases, shrinking of the full thickness skin grafts was noted. Both of them received physiotherapy and gained nearly complete function of the injured hand and wrist. When larger parts of skin are lost in degloving injuries meshing the degloved skin as full thickness skin grafts good wound coverage of larger, contaminated defects can be achieved.

Experience of total knee arthroplasty using a novel navigation system within the surgical field.

BACKGROUND: With the aim of improving component alignment and outcome in total knee arthroplasty (TKA), several computer-assisted devices (CAD) have been developed. METHODS: In February 2014, the present unit started to use a new imageless navigation system with accelerometric pods within the surgical field for all primary TKAs; there was no need for optical trackers or cameras. This paper presents the results of the first 72 TKAs using this iAssist system in 71 prospectively collected and retrospectively analyzed patients. It analyzed component positioning in standard and full-length leg x-rays. RESULTS: The mean age of the patients was 70years (range 52-88). The center of hip, knee and ankle (mechanical axes) deviated on average 0.5° (standard deviation (SD) of 1.8) valgus from the targeted straight alignment. Three TKAs had >3° deviation (i.e. four degree varus, five degree and seven degree valgus). The frontal tibial tray alignment was an average of 89.9° (range 86.4-100.1°, SD ±2.0) with the target being 90°, and the sagittal slope was as targeted at 85.0° (range 78.4-88.8°, SD ±1.7). CONCLUSIONS: This CAD facilitated good mechanical alignment and reproducible accuracy in component positioning. Pods clipped onto cutting jigs within the surgical field provided simple and accurate navigation, with little extra time needed for calibration and no need for optical trackers or pre-operative imaging.

O2C Laser Doppler and Digital Photo Analysis for Treatment Evaluation of Beta-Glucan versus Provitamin Pantothenic Acid of Facial Burns.

Various creams are available for superficial second-degree burns (SSDB) of the face. We evaluated provitamin pantothenic acid versus ß-glucan for SSDB of the face using the O2C laser Doppler system and digital photo analysis. Out of 20 patients (January to December 2012) with facial burns, 7 with SSDB of both cheeks were included to our study. Burned cheek wounds were treated using pantothenic acid or ß-glucan. Digital photos of marked regions were taken daily from predefined distances. Microcirculation was measured at marked regions for 7 days at scheduled time points using the O2C laser Doppler. Data were evaluated using the SPSS program (SPSS Inc., Chicago, IL). Wounds treated with ß-glucan showed faster reepithelialization. O2C laser Doppler measurements showed faster increase in SO2, microvascular perfusion, hemoglobin content, and blood flow. This correlated good with clinical Vancouver Scar Scale results. Although not statistically significant, ß-glucan cream therapy of SSDB results in aesthetically superior outcome and faster reepithelialization.

Optimizing Biomaterials for Tissue Engineering Human Bone Using Mesenchymal Stem Cells.

BACKGROUND: Adequate biomaterials for tissue engineering bone and replacement of bone in clinical settings are still being developed. Previously, the combination of mesenchymal stem cells in hydrogels and calcium-based biomaterials in both in vitro and in vivo experiments has shown promising results. However, results may be optimized by careful selection of the material combination. METHODS: ß-Tricalcium phosphate scaffolds were three-dimensionally printed with five different hydrogels: collagen I, gelatin, fibrin glue, alginate, and Pluronic F-127. The scaffolds had eight channels, running throughout the entire scaffold, and macropores. Mesenchymal stem cells (2 × 10) were mixed with each hydrogel, and cell/hydrogel mixes were dispersed onto the corresponding ß-tricalcium phosphate/hydrogel scaffold and cultured under dynamic-oscillating conditions for 6 weeks. Specimens were harvested at 1, 2, 4, and 6 weeks and evaluated histologically, radiologically, biomechanically and, at 6 weeks, for expression of bone-specific proteins by reverse-transcriptase polymerase chain reaction. Statistical correlation analysis was performed between radiologic densities in Hounsfield units and biomechanical stiffness. RESULTS: Collagen I samples had superior bone formation at 6 weeks as demonstrated by volume computed tomographic scanning, with densities of 300 HU, similar to native bone, and the highest compression values. Bone specificity of new tissue was confirmed histologically and by the expression of alkaline phosphatase, osteonectin, osteopontin, and osteocalcin. The bone density correlated closely with histologic and biomechanical testing results. CONCLUSION: Bone formation is supported best by ß-tricalcium phosphate/collagen I hydrogel and mesenchymal stem cells in collagen I hydrogel. CLINICAL QUESTION/LEVEL OF EVIDENCE: Therapeutic, V.

A comparison of complications in 400 patients after native nail versus silicone nail splints for fingernail splinting after injuries.

BACKGROUND: The fingertip is the most commonly injured part of the hand and is an important aesthetic part of the hand. METHODS: In this retrospective study we analyzed data from 700 patients operated on between 1997 and 2008 for complications after nail splinting with native nail or silicone nail. Inclusion criteria were patients living in Bern/Berner Land, complete documentation, same surgical team, standard antibiotics, acute trauma, no nail bed transplantation, and no systemic diseases. Groups were analyzed for differences in age, gender, cause and extension of trauma, bony injury and extent, infection, infectious agent, and nail deformities. Statistical analysis was done using the χ (2) test, Fisher's exact test, and Pearson correlation coefficients. RESULTS: A total of 401 patients, with a median age of 39.5 years, were included. There were more men with injured nails. Two hundred forty native nails and 161 silicone splints were used. There were 344 compression injuries, 44 amputations, and 13 avulsion injuries. Forty-three patients had an infection, with gram-positive bacteria (Staphylococcus aureus) causing most infections. A total of 157 nail dystrophies were observed, split nails most often. The native nail splint group showed significantly (p < 0.015) fewer nail deformities than the silicone nail splint group; otherwise, there were no statistical differences. However, there were twice as many infections in the silicone nail group. CONCLUSION: It seems to be advantageous to use the native nail for splinting after trauma, when possible. In case of a destroyed and unusable nail plate, a nail substitute has to be used.

Deep sternal osteomyelitis: an algorithm for reconstruction based on wound width.

Patients with sternum osteomyelitis are transferred to plastic surgery departments for wound coverage. Several options of flap coverage are known; however, various wound diameters need different flaps. In a retrospective study, 135 patients from 2006-2010 with deep sternal wound infections were evaluated. From 2006-2009 various flaps were used for wound coverage, as described in published reports. In 2010 a developed algorithm was used for defect coverage based on wound width using pectoralis muscle flaps or the latissimus dorsi muscle flap. Two groups of patients were analyzed, from 2006-2009 and 2010, and in a matched pair analysis patients with small wound width less than 6 cm, medium wounds widths between 6-12 cm, and large wound width larger than 12 cm. End-point was wound dehiscence larger than 1 cm. Statistical analysis was done by Mann Whitney U-test using the SPSS program. Forty-eight patients were included in the match from a total of 130 study patients. Statistical analysis did not show significant difference in patient population of the two groups. In the group with wound sizes less than 6 cm a significant difference was found when using the algorithm. In the other groups no statistically significant difference was seen; however lesser numbers in wound dehiscence were found. In addition, a significantly lesser length of stay was found in the ICU and length of the hospital stay for all groups treated according to the algorithm. A reduction of costs may be achieved when using the algorithm based on wound size.

Incidence and treatment of burns: a twenty-year experience from a single center in Germany.

OBJECTIVE: To analyze trends in incidence and treatment of thermal injuries over the last two decades. METHODS: We retrospectively reviewed our local single center database of patients with thermal injuries admitted to the burn intensive care unit (BICU) of the Cologne-Merheim Medical Center (University Hospital of Witten/Herdecke). The cohort was divided into two groups according to the decade of admission and the epidemiology and clinical course of the patient sample admitted during the period 1991-2000 (n=911) was compared to that of 2001-2010 (n=695). RESULTS: The following variables were significantly different in the bivariate analysis: mean age (39.8 years vs. 44.0 years), burn size of total body surface area (23.2% vs. 18.0%) and size of 3rd degree burns (9.6% vs. 14.9%). The incidence of inhalation injury was significantly lower in the last decade (33.3% vs. 13.7%) and was associated with a shorter duration of mechanical ventilation (10.8 days vs. 8.5 days). The ABSI-score as an indicator of burn severity declined in the second period (6.3 vs. 6.0) contributing partially to the decline of BICU length of stay (19.1 days vs. 18.8 days) and to the mortality rate decrease (18.6% vs. 15.0%). CONCLUSION: The severity of burn injuries during the last two decades declined, probably reflecting the success of prevention campaigns. Concerning mortality, the chance of dying for a given severity of injury has decreased.

Failure of secondary wound closure after sternal wound infection following failed initial operative treatment: causes and treatment.

BACKGROUND: Patients transferred to Plastic Surgery Departments for sternum osteomyelitis have a high morbidity of about 3%. Despite several known options for sternal wound coverage and salvage operations, wound dehiscence or wound necrosis can occur, increasing patient morbidity. PATIENTS AND METHODS: One hundred thirty-five patients admitted between January 2007 and December 2010 were evaluated in a retrospective study for wound dehiscence after salvage wound coverage at our institution. Various flaps were applied, such as pectoralis major myocutaneous pedicled flaps, pectoralis major muscle pedicled flaps, latissimus dorsi pedicled flaps, greater omental flaps, and vertical rectus abdominis muscle and transverse rectus abdominis muscle flaps. Inclusion criteria were sternal wound infection, bacterial wound infection, previous wound debridement outside our institution, vacuum-assisted closure device wound treatment at our institution, and secondary flap closure of the sternal defect at our institution. A multivariate regression analysis was performed. RESULTS: One hundred thirty patients met the inclusion criteria. In all patients, bacterial wound colonization was shown. Forty patients showed wound dehiscence after closure at our institution. Reasons for wound dehiscence were attributed to wound size, >4 different species of bacteria colonizing the wound, gram-negative bacteria, Candida albicans, intensive care unit stay, and female gender. Interestingly, wound dehiscence was not significant correlated to obesity, smoking, atherosclerosis, renal insufficiency or type of closure influenced significantly, or necrosis. CONCLUSIONS: Female patients after CABG, with large sternal wounds infected with gram-negative bacteria and candida, have an 85% risk of wound dehiscence after flap coverage for sternal wound infection.

Technique and indication of distal arterial-to-proximal venous anastomosis at an amputated distal phalanx.

Digital finger amputation with soft tissue injury is a frequent accident in reconstructive surgery. Several techniques about reconstruction of digital finger amputation are described in literature. However replantation is difficult when large segments of the arteries are missing. This is especially true for distal finger phalanx amputations, where replantation is done in selected patients such as artists or musicians. In this article a microsurgical replantation techniques of a distal artery and proximal vein anastomosis is presented in a distal phalanx amputation, which successfully solved the problem of venous reflux without venous anastomosis.

Thoracic radionecrosis following repeated cardiac catheterization.

Radiodermatitis is a known complication in patients having undergone radiotherapy. It usually appears 2 to 5 years after irradiation. We are reporting on a case of radiodermatitis that occurred within months after coronary dilatation and stenting. It started with painful swelling, followed by a typical appearance on the skin surface. Histological finding confirmed the diagnosis. However, magnetic resonance imaging showed changes in the subcutaneous tissue extending into the ribs. A radical debridement was performed including removal of a partially necrotic 4th rib. The defect was closed with a latissimus dorsi transposition flap. Our findings are compared with the literature reports.

Combined latissimus dorsi and serratus anterior flaps for pelvic reconstruction.

In recurrent pressure sores, adjacent tissue has already been consumed by multiple surgeries. Additional problems are several co-morbidities of patients. Especially, severe atherosclerosis would be a contraindication for using free flaps. However, microsurgical techniques allow circumventing these limitations and preparing even severely atherosclerotic vessels. We performed a total of eight sacral pressure sore coverage in our standardized fashion, using the free combined latissimus dorsi and serratus anterior free flaps. All patients had severe atherosclerosis and needed large soft tissue coverage of the sacral defects. Five patients presented after bowel resection, three with recurrent sacral pressure sores. The average follow-up was 12 months. Postoperatively, all patients were allowed to be prone on the operated area. One minor wound dehiscence was sutured in local anesthesia. CT imaging analysis of the pelvis showed complete void space coverage. The combined latissimus dorsi and serratus anterior flaps are a valuable tool for pelvic reconstruction in our hands. In addition, severe atherosclerosis should not be considered an obstacle to microsurgery and the use of free flaps.

Suicide by burning: epidemiological and clinical profiles.

Self-immolation constitutes a rare form of suicide in developed countries, though it accounts for unique injury characteristics in the burn intensive care unit. The aim of this study was to present the epidemiological and clinical features of patients burned during a suicidal attempt seen in a North Rhine-Westphalia burn intensive care unit (BICU). To address this aim, we undertook a 21-year retrospective study involving patients with thermal injuries admitted to the largest burn unit in Germany. A total of 125 suicide-related burn victims were identified in the study period (9.4%). Comparing the self-immolation group with the rest burn patient cohort, suicide victims were more likely to be single and to act under the influence of alcohol. The suicidal group had a larger extent of burns, higher incidence of inhalation injury, required more surgical procedures, catecholamines, blood transfusions, and a longer BICU stay. Their clinical course was complicated by prolonged intubation period, higher rate of multiple drug-resistant bacteria acquisition and sepsis, leading to a higher mortality rate. Although the proportion of self-immolation victims among all burned patients is not high, the markedly higher severity of their burns and their poorer quality of outcomes makes them an important clinical subgroup for further study.

Factors of osteogenesis influencing various human stem cells on third-generation gelatin/ß-tricalcium phosphate scaffold material.

Human bone marrow-derived stem cells (hBMSCs) and adipose-derived stem cells (hASCs) have been used to regenerate bone. Both sources are claimed to have comparable osteogenic potential, but few comparative studies are available. Third-generation biomaterials have been developed to reduce steps in regenerating tissues. For osteogenesis gelatin/ß-tricalcium phosphate (ß-TCP) scaffolds with incorporated controlled-release bone morphogenetic protein-2 (BMP-2) as third-generation biomaterials were recently developed. So far, few studies on protein-induced osteogenesis versus chemical-induced osteogenesis have been performed. This study evaluates the osteogenic potential of hBMSCs versus hASCs derived on gelatin/ß-TCP scaffolds in vitro under four different conditions. Gelatin/ß-TCP scaffolds with and without incorporated controlled-release BMP-2 were seeded with hBMSCs or hASCs under oscillating fluid conditions in osteogenic (OS) medium or growth medium (GM). All were evaluated radiologically (computed tomography [CT] scan), histologically, biomechanically, and for gene expression at 1, 2, 4, and 6 weeks. The highest radiological densities were seen in specimens at 6 weeks with controlled-release BMP-2, close to native bone. HBMSCs, hASCs, OS, and GM conditions resulted in similar bone formation with gelatin/ß-TCP scaffolds and incorporated controlled-release BMP-2. This was confirmed histologically by Toluidine Blue and van Kossa staining and biomechanically. Gene expression studies of these specimens showed the presence of preosteoblasts, transitory osteoblasts, and secretory osteoblasts. Specimens comprised of gelatin/ß-TCP scaffolds without incorporated controlled release BMP-2 in OS medium showed lesser bone formation. hASCs and hBMSCs have similar osteogenic potential. hASCs are an attractive alternative to hBMSCs for bone regeneration using third-generation gelatin/ß-TCP scaffolds with incorporated controlled-release BMP-2.

A high bifurcation of the dorsal branch with dominant superficial palmar branch of the radial artery: a case report of an aberrant radial artery with traumatic aneurysm.

Anatomical abnormalities such as unusual bifurcations or aberrant arteries of the radial artery are extremely rare and due to malformation or disruption of the vascular net. We present a case of a 64 year old woman with a high bifurcated dorsal branch of the left radial artery, consulting us for a pulsatile mass in the anatomical snuffbox after a fall. The mass measured 3-4 mm in diameter and was located on the dorsal aspect of the wrist over the anatomical snuffbox. Primary imaging studies using Duplex Ultrasound suggested an aneurysm of the radial artery, further imaging with arteriogram revealed a high bifurcation of the dorsal branch of the radial artery, presenting with an aneurysm. The deep palmar branch of the ulnar artery was the dominating vessel, allowing ligation and excision of the aneurysm. Histological evaluation revealed intimal wall hyperplasia within the aneurysm, suggesting an injury as initiating factor. A review of the literature showed that this abnormality of high bifurcation of the dorsal palmar branch of the radial artery has not been previously reported. Management of aneurysms at the wrist is discussed.

What's behind the mask? A look at blood flow changes with prolonged facial pressure and expression using laser Doppler imaging.

Clinically, the initial blanching in burn scar seen on transparent plastic face mask application seems to diminish with time and movement requiring mask alteration. To date, studies quantifying perfusion with prolonged mask use do not exist. This study used laser Doppler imaging (LDI) to assess perfusion through the transparent face mask and movement in subjects with and without burn over time. Five subjects fitted with transparent face masks were scanned with the LDI on four occasions. The four subjects without burn were scanned in the following manner: 1) no mask, 2) mask on while at rest, 3) mask on with alternating intervals of sustained facial expression and rest, and 4) after mask removal. Images were acquired every 3 minutes throughout the 85-minute study period. The subject with burn underwent a shortened scanning protocol to increase comfort. Each face was divided into five regions of interest for analysis. Compared with baseline, mask application decreased perfusion significantly in all subjects (P < .0001). Perfusion did not change during the rest period. There were no significant differences with changing facial expression in any of the regions of interest. On mask removal, all regions of the face demonstrated a hyperemic effect with the chin (P = .05) and each cheek (P < .0001) reaching statistical significance. Perfusion levels did not return to baseline in the chin and cheeks after 30 minutes of mask removal. Perfusions remain constantly low while wearing the face mask, despite changing facial expressions. Changing facial expressions with the mask on did not alter perfusion. Hyperemic response occurs on removal of the mask. This study exposed methodology and statistical issues worth considering when conducting future research with the face, pressure therapy, and with LDI technology.

Conditions affecting cell seeding onto three-dimensional scaffolds for cellular-based biodegradable implants.

Seeding cells efficiently and uniformly onto three-dimensional scaffolds is a key element for engineering tissues, particularly when only a low-number of cells is available for tissue repair and regeneration. The aim of this study was to evaluate three seeding techniques on two biocompatible scaffolds in vitro using chondrocytes as follows: (1) static; (2) modified centrifugal cell immobilization (CCI); and (3) dynamic oscillating motion. Five milliliters of media containing 5, 10, or 25 million articular, auricular, or costal chondrocytes were used to seed porous PLGA scaffolds and sections of devitalized cartilage. The dynamic oscillating technique resulted in up to 150% higher cellular load at 7 days than CCI seeding. Cell distribution was more homogeneous throughout the scaffold under dynamic conditions versus more sporadic and dispersed cell concentrations on the scaffolds when using either the static or the modified CCI technique. Cell load and distribution, when using a low numbers of chondrocytes at one and two million cells per milliliter, was comparable to that using the much higher number, especially under dynamic seeding conditions. The seeded scaffolds were used as implants to achieve cellular bonding between two devitalized meniscus discs. The constructs were implanted subcutaneously in nude mice for 12 weeks and analyzed histologically. Implants seeded with auricular chondrocytes showed qualitative more integration into native meniscus tissue than articular and costal cell implants. We conclude the dynamic oscillating seeding technique is an efficient technique for seeding low-cell numbers onto scaffolds resulting in consistent and uniform cell distribution throughout porous PLGA scaffolds.

Toward regenerating a human thumb in situ.

Regenerative technology promises to alleviate the problem of limited donor supply for bone or organ transplants. Most expensive and time consuming is cell expansion in laboratories. We propose a method of magnetically enriched osteoprogenitor stem cells, dispersed in self-assembling hydrogels and applied onto new ultra-high resolution, jet-based, three-dimensional printing of living human bone in a single-step for in situ bone regeneration. Human bone marrow-derived mesenchymal stem cells (hBMSCs) were enriched with CD 117+ cells, dispersed in different collagen I and RAD 16I hydrogel mixes, and applied onto three-dimensional printed btricalcium phosphate=poly(lactic-co-glycolic acid) scaffolds, printed from ultra-high-resolution volumetric CT images of a human thumb. Constructs were directly implanted subcutaneously into nude mice for 6 weeks. In vivo radiographic volumetric CT scanning and histological evaluations were performed at 1, 2, 4, and 6 weeks, and expression of bone-specific genes and biomechanical compression testing at 6 weeks endpoint. Time-dependant accumulation of bone-like extracellular matrix was most evident in CD 117+ hBMSCs using collagen I=RAD 16I hydrogel mix. This was shown histologically by Toluidine blue, von Kossa, and alkaline phosphatase staining, paralleled by increased radiological densities within implants approximating that of human bone, and confirmed by high expression of bone-specific osteonectin and biomechanical stiffness at 6 weeks. Human origin of newly formed tissue was established by expression of human GAPDH using RT-PCR. Statistical analysis confirmed high correlations between biomechanical stiffness, radiological densities, and bone markers. Bone tissue can be successfully regenerated in vivo using a single-step procedure with constructs composed of RAD 16I=collagen I hydrogel, CD 117+-enriched hBMSCs, and porous b-tricalcium phosphate=poly(lactic-co-glycolic acid) scaffolds.

Using ordinal logistic regression to evaluate the performance of laser-Doppler predictions of burn-healing time.

BACKGROUND: Laser-Doppler imaging (LDI) of cutaneous blood flow is beginning to be used by burn surgeons to predict the healing time of burn wounds; predicted healing time is used to determine wound treatment as either dressings or surgery. In this paper, we do a statistical analysis of the performance of the technique. METHODS: We used data from a study carried out by five burn centers: LDI was done once between days 2 to 5 post burn, and healing was assessed at both 14 days and 21 days post burn. Random-effects ordinal logistic regression and other models such as the continuation ratio model were used to model healing-time as a function of the LDI data, and of demographic and wound history variables. Statistical methods were also used to study the false-color palette, which enables the laser-Doppler imager to be used by clinicians as a decision-support tool. RESULTS: Overall performance is that diagnoses are over 90% correct. Related questions addressed were what was the best blood flow summary statistic and whether, given the blood flow measurements, demographic and observational variables had any additional predictive power (age, sex, race, % total body surface area burned (%TBSA), site and cause of burn, day of LDI scan, burn center). It was found that mean laser-Doppler flux over a wound area was the best statistic, and that, given the same mean flux, women recover slightly more slowly than men. Further, the likely degradation in predictive performance on moving to a patient group with larger %TBSA than those in the data sample was studied, and shown to be small. CONCLUSION: Modeling healing time is a complex statistical problem, with random effects due to multiple burn areas per individual, and censoring caused by patients missing hospital visits and undergoing surgery. This analysis applies state-of-the art statistical methods such as the bootstrap and permutation tests to a medical problem of topical interest. New medical findings are that age and %TBSA are not important predictors of healing time when the LDI results are known, whereas gender does influence recovery time, even when blood flow is controlled for.The conclusion regarding the palette is that an optimum three-color palette can be chosen 'automatically', but the optimum choice of a 5-color palette cannot be made solely by optimizing the percentage of correct diagnoses.