Necrotizing fasciitis caused by mono-bacterial gram-negative infection with E. coli - the deadliest of them all: A case series and review of the literature.

INTRODUCTION: Unlike other skin and soft tissue infections, necrotizing fasciitis (NF) is a very rare but potentially fatal condition. Common organisms causing NF are poly-microbial (type I) infection with mixed organisms and mono-bacterial gram-positive infection with mainly streptococci (type II). Mono-bacterial gram-negative NF is a rare form of NF that is not included in the current classification. CASE SERIES: We report four cases of mono-bacterial gram-negative NF caused by E. coli. All patients presented in septic shock and showed landscape-like skin necrosis and pain out of proportion. Radical debridement and escalation of antibiotic treatment was performed in all patients. Short-term survival was 50%. Two patients died of multiorgan failure. Two patients survived short term: One patient was amputated through the knee but died six months later of metastatic prostate cancer. One patient was covered with split thickness skin grafts and died three months later of catheter-associated sepsis with endocarditis. DISCUSSION: Recent findings suggest adding a type III fasciitis, which is caused by mono-bacterial gram-negative organisms. As patients are getting older with even more comorbidities, mono-bacterial gram-negative NF will be an increasing problem for physicians treating soft tissue and skin infections.In oncologic diseases, liver cirrhosis, renal diseases or otherwise immunocompromised patients, mono-bacterial gram-negative NF with E. coli is underestimated. Therefore, in these patients, antibiotic treatment should cover Gram-negative organisms including E. coli. However even with adjusted antibiotic treatment and radical debridement, the short-term survival and long-term outcome are poor.

Experimental investigation of D2 conversion to DHO in soil near the Cernavoda nuclear power plant site in Romania.

The current Canadian and Romanian model predictions for tritium dose following an atmospheric tritiated hydrogen gas (HT) release is based on a default Canadian Standards Association (CSA) conversion factor of HT to tritiated water (HTO) of 4.3%. The determination of an empirical site specific value for the conversion factor was essential for the CANDU Cernavoda Nuclear Power Plant (NPP) in Romania to verify if the CSA value is appropriate for use at this site. Given the role of soil characteristics on the conversion of HT to HTO, on-site experiments would provide the best evaluation of the conversion factor. The objective of the study was to define the soil HT to HTO conversion parameters specific to the Cernavoda NPP site. In June 2016, a series of experiments were conducted to meet this objective. First, the in situ deposition velocity of D2 gas, as a surrogate for HT gas, was obtained using an exposure chamber. Diffusion of D2 into the soil was then evaluated based on the measurements of DHO concentrations in the exposed soil. As soil microbes play a role in the conversion of HT to HTO, this work included a microbiological characterization of the soil, which targeted total soil bacteria (cultivable and gene-based) and hydrogen oxidizing bacteria (cultivable and gene-based). The fraction of hydrogen oxidizing cultivable soil bacteria represented 14-20% of the total cultivable bacteria population estimated as 2.8-29.2 × 105 cfu/g of soil. The empirically derived HT to HTO conversion factor was lower than the default value (4.3%). It fell between 0.9% and 2.0%. The default value is therefore more conservative than the Cernavoda site-specific derived value obtained from the study.

Evaluation of discriminant functions for sexing skulls from visually assessed traits applied in the Rainer Osteological Collection (Bucharest, Romania).

The sexing of human skeletal remains based on visual scoring of descriptive traits on the skull is useful for both forensic and bioarchaeological studies, given that many such features preserve well in the field and can be assessed quickly. The goal of our work is to evaluate the accuracy of this method on an age-balanced, known sex, random sample of 360 modern adult crania in the Rainer Osteological Collection. Consistent with Walker (2008), we scored glabella area (G), the mastoid process (Ma), the mental eminence (M), the orbital edge (O) and the nuchal crest (N), on a five-point scale. We generated sex discriminant functions (logistic), selected the most accurate of them, and subsequently applied them to archaeological samples from Romania. Each skull feature showed significant score differences by sex. Eight out of 31 discriminant functions passed criteria of high accuracy (∼90%), sex bias (±2%), and ease of use (direct calculation of sex). The best estimates were obtained for the 30-60 age groups. Further testing these functions on six archaeological samples showed high percentages of agreement with the sex assessed on the coxal bone. The study also indicated that, although easy to learn by novices, the method of visually scoring the skull traits depends on prior experience with human osteology. The accuracy of the method may be influenced by geographical and historical differences which are bound to exist between populations.

Body contouring surgery following bariatric surgery and dietetically induced massive weight reduction: a risk analysis.

BACKGROUND: This study analyzed the impact of weight reduction method, preoperative, and intraoperative variables on the outcome of reconstructive body contouring surgery following massive weight reduction. METHODS: All patients presenting with a maximal BMI >/=35 kg/m(2) before weight reduction who underwent body contouring surgery of the trunk following massive weight loss (excess body mass index loss (EBMIL) >/= 30%) between January 2002 and June 2007 were retrospectively analyzed. Incomplete records or follow-up led to exclusion. Statistical analysis focused on weight reduction method and pre-, intra-, and postoperative risk factors. The outcome was compared to current literature results. RESULTS: A total of 104 patients were included (87 female and 17 male; mean age 47.9 years). Massive weight reduction was achieved through bariatric surgery in 62 patients (59.6%) and dietetically in 42 patients (40.4%). Dietetically achieved excess body mass index loss (EBMIL) was 94.20% and in this cohort higher than surgically induced reduction EBMIL 80.80% (p < 0.01). Bariatric surgery did not present increased risks for complications for the secondary body contouring procedures. The observed complications (26.9%) were analyzed for risk factors. Total tissue resection weight was a significant risk factor (p < 0.05). Preoperative BMI had an impact on infections (p < 0.05). No impact on the postoperative outcome was detected in EBMIL, maximal BMI, smoking, hemoglobin, blood loss, body contouring technique or operation time. Corrective procedures were performed in 11 patients (10.6%). The results were compared to recent data. CONCLUSION: Bariatric surgery does not increase risks for complications in subsequent body contouring procedures when compared to massive dietetic weight reduction.

Tight contact technique during side-to-side laser tissue soldering of rabbit aortas improves tensile strength.

BACKGROUND: Cerebral revascularization may be indicated either for blood flow preservation or flow augmentation, often in clinical situations where neither endovascular nor standard surgical intervention can be performed. Cerebral revascularization can be performed by using a temporary occlusive or a non-occlusive technique. Both of these possibilities have their specific range of feasibility. Therefore non-occlusive revascularization techniques have been developed. To further reduce the risks for patients, less time consuming, sutureless techniques such as laser tissue soldering are currently being investigated. METHOD: In the present study, a new technique for side-to-side anastomosis was developed. Using a "sandwich technique", two vessels are kept in close contact during the laser soldering. Thoraco-abdominal aortas from 24 different rabbits were analyzed for laser irradiation induced tensile strength. Two different irradiation modes (continuous and pulsed) were used. The results were compared to conventional, noncontact laser soldering. Histology was performed using HE, Mason's Trichrome staining. FINDINGS: The achieved tensile strengths were significantly higher using the close contact "sandwich technique" as compared to the conventional adaptation technique. Furthermore, tensile strength was higher in the continuously irradiated specimen as compared to the specimen undergoing pulsed laser irradiation. The histology showed similar denaturation areas in both groups. The addition of a collagen membrane between vessel components reduced the tensile strength. CONCLUSION: These first results proved the importance of close and tight contact during the laser soldering procedure thus enabling the development of a "sandwich laser irradiation device" for in vivo application in the rabbit.

[Revision surgery after carpal tunnel release using a posterior interosseous artery island flap]. / Revisionschirurgie des karpaltunnelsyndroms - ergebnisse der behandlung mit der dorsalen vorderarmlappenplastik.

PURPOSE: The aim of this study is to evaluate the results of fasciocutaneous posterior interosseous artery island flaps in the treatment of recurrent or persistent carpal tunnel compression syndrome (CTS). PATIENTS AND METHODS: From 1997 to 2006, 14 patients (8 women, 6 men, ages ranging from 26 to 77 years with a mean age of 55.7 years) have been operated for recurrent or persistent CTS, or for a neuropathic pain syndrome. All patients were treated with a posterior interosseous island flap following neurolysis of the scarred median nerve. The patients were evaluated pre- and postoperatively using a pain visual analogue scale and the DASH score. Sensibility, motor dysfunction, pain and success of the treatment were classified as good, better or bad. RESULTS: Mean follow-up of the patients was 23.8 months (1.7 to 93.5 months). The pain evaluation showed a statistically significant improvement (p < 0.005) decreasing from a mean value of 6.7 to 1.5. The DASH score was also statistically significantly improved postoperatively (p < 0.005). The best results were observed in patients without extensive preliminary median nerve damage. The duration of symptoms before re-operation did not influence the outcome. Seven patients demonstrated good, five improved and two patients maintained poor results. The two patients with poor results suffered from extremely scarred and injured median nerves following previous carpal tunnel surgery. CONCLUSION: Protective coverage of the median nerve by use of a fasciocutaneous island flap after failure of carpal tunnel release provides a good gliding tissue cover and reduces the risk of adhesions between the nerve and the surrounding tissues after previous surgery. While this protection of the nerve can reduce painful symptoms it does not guarantee total pain relief in all patients. Pain relief and functional recovery strongly depend on the preexisting condition of the median nerve.

Surgical management of gynecomastia--a 10-year analysis.

BACKGROUND: Gynecomastia is defined as the benign enlargement of the male breast. Most studies on surgical treatment of gynecomastia show only small series and lack histopathology results. The aim of this study was to analyze the surgical approach in the treatment of gynecomastia and the related outcome over a 10-year period. PATIENTS AND METHODS: All patients undergoing surgical gynecomastia corrections in our department between 1996 and 2006 were included for retrospective evaluation. The data were analyzed for etiology, stage of gynecomastia, surgical technique, complications, risk factors, and histological results. RESULTS: A total of 100 patients with 160 operations were included. Techniques included subcutaneous mastectomy alone or with additional hand-assisted liposuction, isolated liposuction, and formal breast reduction. Atypical histological findings were found in 3% of the patients (spindle-cell hemangioendothelioma, papilloma). The surgical revision rate among all patients was 7%. Body mass index and a weight of the resected specimen higher than 40 g were identified as significant risk factors for complications (p < 0.05). CONCLUSIONS: The treatment of gynecomastia requires an individualized approach. Caution must be taken in performing large resections, which are associated with increased complication rates. Histological tissue analysis should be routinely performed in all true gynecomastia corrections, because histological results may reveal atypical cellular pathology.

Effects of local continuous release of brain derived neurotrophic factor (BDNF) on peripheral nerve regeneration in a rat model.

The purpose of this study was to evaluate the effect of continuously released BDNF on peripheral nerve regeneration in a rat model. Initial in vitro evaluation of calcium alginate prolonged-release-capsules (PRC) proved a consistent release of BDNF for a minimum of 8 weeks. In vivo, a worst case scenario was created by surgical removal of a 20-mm section of the sciatic nerve of the rat. Twenty-four autologous fascia tubes were filled with calcium alginate spheres and sutured to the epineurium of both nerve ends. The animals were divided into 3 groups. In group 1, the fascial tube contained plain calcium alginate spheres. In groups 2 and 3, the fascial tube contained calcium alginate spheres with BDNF alone or BDNF stabilized with bovine serum albumin, respectively. The autocannibalization of the operated extremity was clinically assessed and documented in 12 additional rats. The regeneration was evaluated histologically at 4 weeks and 10 weeks in a blinded manner. The length of nerve fibers and the numbers of axons formed in the tube was measured. Over a 10-week period, axons have grown significantly faster in groups 2 and 3 with continuously released BDNF compared to the control. The rats treated with BDNF (groups 2 and 3) demonstrated significantly less autocannibalization than the control group (group 1). These results suggest that BDNF may not only stimulate faster peripheral nerve regeneration provided there is an ideal, biodegradable continuous delivery system but that it significantly reduces the neuropathic pain in the rat model.

Anatomy of the proximal cutaneous perforator vessels of the gracilis muscle.

An anatomic study was performed to analyse the proximal perforator vessels of the gracilis musculocutaneous flap. Twenty-three cadaver legs preserved by the method of Thiel were carefully dissected 24h after the proximal vascular pedicle was injected with a red silicone mass. Nine additional cadaver legs were injected with ink, to visualise the skin area supplied by the proximal perforators, respectively, clarified by a modified Spalteholz technique to demonstrate the anatomic course of the perforators. A considerable variation in numbers and localisation of proximal cutaneous perforators was found. One to four perforators were seen within an area of 6 x 6 cm(2) at the entrance of the main pedicle into the proximal gracilis muscle. Their external diameter ranged from 0.5 to 1.0 mm. The ink-injections showed an oval shaped angiosome with a mean surface of 88 cm(2) at the level of the proximal gracilis pedicle. We conclude from this anatomic study, that a cutaneous flap based on the medial circumflex femoral gracilis perforators can be harvested by experienced hands bearing in mind the unpredictable perforator-anatomy.

[Effect of surgical laser on collagen-rich tissue]. / Untersuchungen zur Wirkung chirurgischer Laser auf kollagenreiche Gewebe.

The goal of this ex-vivo study was a controlled macroscopical and microscopical comparison of the immediate effects of surgical lasers on dense collagenous tissues. The investigation of the exact denaturizing effects following tissue interaction between lasers and collagenous fibers are of importance for a better understanding of the observed and described healing process. Partial tenotomies were performed ex vivo on sixty tendons of the flexor digitorum profundus muscle of New Zealand White Rabbits using four surgical lasers (Holmium:YAG-, Erbium:YAG-, Neodym:YAG-, and CO2-Laser). The tendons were evaluated macroscopically, histologically and observations were made on the surgical handling of the lasers during the procedure. The choice of lasers allowed the comparison of a wide spectrum of wavelengths (gamma = 1.0 to 10.6 microns). In addition, beam delivery modalities were compared to each other (focus vs. contact). The pulse (frequency and power) was varied within each laser. Other parameters including focus size, absorption, dispersion, and thermal tissue conductivity were maintained constant in this test arrangement in order to allow a later comparison between the observed areas of denaturated collagen. The macroscopical and histological results showed great differences in the effects of the four lasers. Even within each single laser group, the results varied greatly with the choice of variable parameters. Holmium:YAG- and CO2-Laser can produce similar areas of collagen denaturation. When comparing specimens with similar areas of collagen denaturation induced by different laser types, different amounts of charring were observed. Erbium:YAG-Laser tenotomies showed generally inhomogeneous denaturation areas, while tenotomies with Neodym: YAG-Laser used in continuous mode resulted in significant charring and tissue retraction in the area of interaction. These observations help in defining the combination of parameters with which Holmium:YAG-, Erbium:YAG-, and CO2-Lasers can be used for transsection of dense collagenous tissues. In addition, these histological results as well as already published observations on healing patterns following laser surgery allow for the formulation of a hypothesis on the effects of laser in the wound healing process.

Effect of early mobilization on healing of nerve repair: histologic observations in a canine model.

The effect of early mobilization on the healing of nerve repair was studied in a canine model. Median and ulnar nerves in the left wrist of 16 adult mongrel dogs were transected and immediately repaired. No motion of the repaired forelimb was allowed in the immobilized group (n = 10), while controlled passive motion between 30 and 90 degrees of wrist flexion was begun on the first postoperative day for 10 minutes twice daily in the mobilized group (n = 6). The pattern of revascularization and collagen formation at neurorrhaphy was examined by transillumination of India ink-injected specimen and by conventional histologic sections. Revascularization of nerve repair was found to occur by ingrowth of capillaries from proximal and distal nerve ends, which typically crossed the neurorrhaphy by 3 weeks in the immobilized group. Following early mobilization, there was a persistent "hypovascular zone" at the nerve repair site for up to 6 weeks. In addition, more scar tissue was generated by early motion according to gross observation and quantitative collagen analysis. Early mobilization, therefore, seems to impede nerve regeneration by delaying revascularization and enhancing scar formation.

Refinements in extracorporal septoplasty.

Septal deviations interfere with nasal airflow and contribute to deformities in the external appearance of the nose. An aesthetically and functionally satisfactory correction of severe septal deformities or "crippled" septal plates often requires a temporary intraoperative removal of the septal cartilage for appropriate remodeling. This article describes refinements to the previously described technique of extracorporal septoplasty; these refinements have proven useful and have made the procedure safer in the hands of less experienced surgeons. The refinements simplify the straightening methods for the explanted septal plate, achieving a stable and median fixation of the replanted septum while maintaining a satisfactory contour of the nasal dorsum. A milling cutter is used to straighten the irregularities of the explanted septal plate and to thin broadly based anterior nasal spines. When necessary, microplates are added to stabilize the osteotomized and medialized anterior nasal spine. The final positioning of the replanted septal plate is greatly enhanced by a rein stitch, transosseous sutures, and multiple quilt stitches. Additionally, direct fixation of the replanted septum to the edges of the upper lateral cartilages further improves the stability of the reconstruction. Finally, particular care should be taken to avoid residual irregularities of the nasal dorsum; it they occur, these irregularities can be covered with a thin cartilaginous splint or a layer of dehydrated fascia lata or autologous temporal fascia. A total of 436 patients who underwent rhinoseptoplasties at the authors' department during a 1-year period were reviewed. Of these patients, 108 presented with severe septal deviations and underwent an extracorporal septoplasty using the refined techniques described herein. Despite the complexity of the procedure, the patients' satisfaction rates were high, independent of the operating surgeon.

The relevance of extracorporeal septoplasty in cleft nose correction.

The aim of this paper is to delineate the importance of the correction of the nasal septum when attempting to improve the nasal shape and function in patients with cleft lip and palate (CLP) deformity. The particular problems of the nasal shape in CLP patients are assessed. Various approaches for adequate correction are reviewed and discussed. The method of extracorporeal septoplasty is presented in detail. This method was used between 1982 and 1997 in 141 out of 332 CLP patients who required septoplasties and appears particularly suited for this purpose since it offers the possibility of reconstructing an almost normal septum. This is necessary in order to achieve both a functionally and an aesthetically good result. Our experience over the past 16 years confirms the advantages of this approach.

Laser treatment for an unusual reactive vascular proliferation.

An unusual case of severe vascular proliferation presenting in the form of haemorrhaging cutaneous lesions on the leg is reported. The similarity between these benign lesions and various malignancies is outlined. The patient healed well when the lesions were excised using a laser under local anaesthetic.

Effects of laser versus scalpel tenolysis in the rabbit flexor tendon.

The use of surgical lasers has been shown to decrease adhesion formation as compared with scalpel control groups in various surgical procedures. The potential benefits of laser technology have not been assessed in the treatment of adherent tendons. The current study was designed to first develop a reliable and reproducible model for consistent adhesion formation following flexor tendon trauma. The second goal was to compare the effects of laser tenolysis procedures on tendon gliding with those of traditional scalpel tenolysis. In phase I, the adhesion-induction model utilized bilateral standardized crush- abrasion injuries to the hind limb digital flexor tendons of New Zealand White rabbits. Following 4 weeks of immobilization, the animals were sacrificed, and peritendoneal adhesions were assessed biomechanically. A significantly higher maximal force was required to extract the adherent tendons from the foot as compared with nontraumatized control tendons. In phase II, six groups of animals underwent the same standardized tendon trauma. Four weeks later the rabbits were randomly assigned to undergo either CO2 laser or holmium:YAG laser tenolysis on one foot. Scalpel lysis was used on the contralateral foot and served as an intraindividual control. Biomechanical assessment was performed at 1, 2, and 4 weeks following tenolysis. Significantly less force was required to extract the treated tendons at 1 and 2 weeks following holmium:YAG laser tenolysis when compared with scalpel or CO2 laser tenolysis. After 4 weeks, differences between holmium:YAG and CO2 laser and scalpel treatment were no longer significant. Extracted tendons were pulled apart to failure, and no difference in breaking strength was noted between groups. We conclude that holmium:YAG laser tenolysis results in easier tendon gliding as compared with scalpel or CO2 laser tenolysis at early time points. Laser tenolysis does not affect intrinsic tendon strength.

Pregnancy in patients with cystic fibrosis.

With increasing life span of patients with CF, more women with CF are becoming pregnant and others are seeking information about the risks involved during pregnancy and delivery. A striking limitation of the available information is the lack of large prospective studies of pregnant patients with CF matched for age and disease severity compared with their non-pregnant cohorts. A study investigating the effect of pregnancy on morbidity and mortality is being completed by the Cystic Fibrosis Foundation. We recommend that all women with CF be offered contraceptive measures and counseling on the maternal and fetal risks of pregnancy, including the genetic risks for the child. The issue of who will raise the child in the event of subsequent morbidity or maternal mortality should ideally be prospectively discussed.

Effects of delay procedures on vasculature and survival of arterialized venous flaps: an experimental study in rabbits.

The effect of delay procedures on the survival of large arterialized venous flaps was studied in a rabbit ear model. Both ears of 25 New Zealand White rabbits (n = 50) were randomized into three operative groups receiving (1) no delay, (2) limited delay, or (3) extensive delay. Two weeks later the ear flap was completely divided, and arterialization of the flap venous tree was achieved by anastomosing the central artery of the ear to the anterior branch of the flap central vein. Survival area of 10 flaps in each group was assessed at 14 days. Flap vasculature was assessed in 10 additional ears in the nondelayed and extensively delayed groups by standardized vascular injections with radiopaque silicon rubber immediately, 6 hours, 24 hours, and 2 weeks after arterialization. Delay procedures significantly increased (p = 0.001, unpaired two-tailed Student's t test) survival of arterialized venous flaps in this model. Whereas all flaps in the non-delayed group underwent total necrosis, the mean viable surface area of the flaps was 67.9 percent in the limited delay group and 94.0 percent in the extensively delayed group. Lastly, angiographic studies suggest that delay procedures prior to arterialization of the venous tree enhance perfusion of the arterial tree by increasing venoarterial communications.

Biomechanical evaluation of the canine and porcine models for experimental craniofacial surgery.

This investigation compared the variation of the biomechanical properties of canine and porcine craniofacial bones in homotypical (same site in opposite sides of an animal) and heterotypical (same site in different animals) sites. Biomechanical analysis is a reliable method to assess bone healing, because fracture repair correlates closely with the changes in biomechanical properties. Paired bone fragments were harvested in nine dogs and nine minipigs from each side of the skull from three different sites-the frontal bone, the supraorbital rim, and the zygomatic arch- and submitted to torque to failure. Maximum torque, stiffness, and toughness were recorded and comparative analysis performed. A normal range of variation between paired craniofacial bones in two useful animal models is provided. The results showed that the variability between homotypic left and right sides was not significant, whereas the variability between heterotypic sites in separate animals was. Maximum torque was the most reliable of the three parameters considered, because the data fell over a much narrower range. We conclude that the use of the contralateral side is a valid control in experimental procedures that may alter the biomechanical properties of one side.