Numerical analysis of Venous External Scaffolding Technology for Saphenous Vein Grafts

This paper presents a method for analyzing and comparing numerically Saphenous Vein Grafts (SVGs) following Coronary Artery Bypass Graft surgery (CABG). The method analyses the flow dynamics inside vein grafts with and without supporting using Venous External Scaffolding Technology (VEST). The numerical method uses patients׳ specific computational fluid dynamics (CFD) methods to characterize the relevant hemodynamic parameters of patients׳ SVGs. The method was used to compare the hemodynamics of six patient׳s specific model and flow conditions of stented and non-stented SVGs, 12 months post-transplantation. The flow parameters used to characterize the grafts׳ hemodynamics include Time Averaged Wall Shear Stress (TAWSS), Oscillatory Shear Index (OSI) and Relative Residence Time (RRT). The effect of stenting was clearly demonstrated by the chosen parameters. SVGs under constriction of VEST were associated with similar spatial average of TAWSS (10.73 vs 10.29 dyn/cm(2)), yet had fewer lesions with low TAWSS, lower OSI (0.041 vs 0.08) and RRT (0.12 vs 0.24), and more uniform flow with less flow discrepancies. In conclusion, the suggested method and parameters well demonstrated the advantage of VEST support. Stenting vein grafts with VEST improved hemodynamic factors which are correlated to graft failure following CABG procedure.

Psychologic consequences of facial dermatoses

The attractiveness of the human body has always been an important issue in the fields of sociology, psychology, and psychiatry and also in the field of dermatology. In psychodermatology, one often discovers how all these fields intermingle to produce elaborate situations and extreme human difficulties. Perfect skin is widely adored in literature, poetry, and biblical texts, as well as in advertisements, movies, and television. Because in most societies the face is the body part that is visible, imperfections of the skin are also visible; therefore, its flawed appearance bears the potential to become a source of misery to some.

Patch testing: facts and controversies

The German dermatologist, Josef Jadassohn (1863-1936), first presented the results of his innovative patch-testing technique in 1895. The safety and efficacy of this diagnostic tool has stood the test of time and is still the gold standard for the diagnosis of allergic contact dermatitis (ACD). Since its discovery, much effort has been put into standardization and optimization of allergens, vehicles, and concentrations of patch-test materials; in procedures of its application; and in reading and scoring of test reactions--all contributing to the development of an accurate, reliable, and safe test with a high reproducibility of its results. Even this seemingly carved-in-stone practice, which has been used for nearly 120 years, has been questioned and challenged, engendering debates, disagreements, and controversies, which show no signs of coming to an end. Almost every step of the procedure has provoked discussions and controversies:

Abnormal epidermal barrier in the pathogenesis of psoriasis

Almost 2 decades ago, Williams and Elias suggested a unifying concept for the pathogenesis of disorders of cornification, according to which the integrity of the epidermal barrier and its effective function is an important factor in the regulation of epidermal DNA synthesis. Interference with the barrier integrity or function will result in epidermal hyperplasia and may be the primary event leading to hyperproliferative skin diseases, such as psoriasis. We have analyzed alterations to several structures of the epidermal barrier that might be responsible for barrier dysfunction and thus lead to hyperproliferation of the epidermis in an attempt to repair the barrier and, as a result, might be inducers of psoriasis. There are several convincing reports indicating that inhibiting of epidermal transglutaminase may lead to epidermal hyperproliferation and that this stimulus might trigger psoriasis among genetically predisposed patients. Disturbance of epidermal barrier function caused by derangement of lipid or cholesterol or ceramide synthesis leads to increased DNA synthesis and epidermal hyperplasia and as a result might be an inducer of psoriasis. We could find little evidence to show that defective defense of the epidermis or an abnormal response of it to bacteria plays a role in the pathogenesis of psoriasis. Accumulating data indicate that there is an association of psoriasis and mutations of genes within the epidermal differentiation complex, which are crucial for the development, maturation, cornification, cross-linking, and terminal differentiation of the epidermis, called psoriasis susceptibility locus 4.

A psychodermatology clinic: the concept, the format, and our observations from Israel

The connection between the brain and the skin is more than a physiologic fact. Skin conditions can impose great effects on every field in the patients' lives. Reciprocally, skin diseases can be evoked by psychological problems. A psychodermatology clinic is the format that enables dermatology patients to receive a comprehensive approach to their skin condition as well as to the difficulties it imposes on their lives, and vice versa. Although the notion that skin and mind are connected and have bilateral influences that should be addressed is now appreciated, it is surprising that such clinics are not more prevalent. In the literature there are only a few descriptions of such clinics, and even fewer descriptions of their format and their working formulations with their pluses and minuses. In this article, we describe in detail the working formulation of a new psychodermatology clinic in Israel, as well as our therapeutic methods, data, conclusions, and observations after the first 3 years. During a 3-year period, 124 patients were seen in our psychodermatology clinic, presenting with a vast array of dermatologic complaints. One of our major observations was that lack of proper patient-doctor communication resulted in the development of misconceptions about the disease, low compliance, and even long-lasting psychological difficulties. Another important observation was that there is a true need for such a clinic, among patients as well as among their doctors.

[A new psycho-dermatology clinic in Israel: our first year experience]

Psychodermatology involves the interrelationships between the skin and the mind, especially when considering the formation and evolution of certain common skin conditions. It appears that 30-40% of dermatology patients suffer from certain psychological problems as defined by the ICD-10, in a way that influences their disease severity and progression, as well as their quality of Life. Treatment of such cases requires a multi-disciplinary approach and should involve both a dermatologist and a mental health specialist working together In this article, the authors summarize the preliminary experience of the first year of the only psychodermatology clinic in Israel in several decades, work methods and patients' characteristics and preliminary conclusions.

Skin care products and subtle data manipulation

The dermatologists of today need to master the skills to help their patients in choosing skin care products. As physicians and scientists, we are naturally inclined to trust sophisticated and objectively derived data that are published in scientific, peer-reviewed journals and are presented to us in the form of numbers, tables, and graphs. The question that should be asked is whether a product that scored well in sophisticated tests is really superior and more suitable to the needs of our patients? Or, how far can we trust the data in scientific publications? There is no generally accepted methodology for unbiased evaluation of the efficacy and performance of skin care products. There is also no consensus on which test method best reflects the real-life performance of these products. And, most importantly, even the most objective methods and measuring devices can be and often are manipulated to support the claims of superiority of given products. We will show several out of many, many ways of how the study design, protocols, techniques, and end points can legitimately be adapted to the special characteristics of the specific product, emphasizing its advantages.

Itch and scratch: scabies and pediculosis

Scabies and lice infestations are almost an everyday diagnosis in the dermatology clinics. Along with the unbearable itch, resistance to medication, secondary infection, and the high risk for spreading the parasite to their close contacts, the patients have also to battle with many myths, prejudice, and shames connected to those infestations.

Drug Rash with Eosinophilia and Systemic Symptoms versus Stevens-Johnson Syndrome – a Case that Indicates a Stumbling Block in the Current Classification

A 43-year-old man developed a skin eruption characterized by 'macules with blisters' typical to Stevens-Johnson syndrome, as well as erosions of the lips and buccal mucosa, 2 weeks after he had started treatment with lamotrigine. He had a fever (39.6 degrees C), elevated liver enzymes and atypical lymphocytes in the peripheral blood. This undoubtedly reflects a case of Stevens-Johnson syndrome induced by lamotrigine, but it can also fulfill the criteria of anticonvulsant hypersensitivity syndrome or drug rash with eosinophilia and systemic signs. A case that precisely fits the definition of two syndromes that have different characteristics, different treatments and different prognoses indicates that there is a flaw in the classification.

The Blue Peel: how to do it less expensively and faster

One well accepted and popular method worldwide for trichloroacetic acid peels is the Obagi Blue Peel technique (Obagi Medical Products, Long Beach, CA). The peel solution is prepared by mixing a fixed volume of 30% trichloroacetic acid with the commercially available Blue Peel base. The authors suggest modifications for performing the peeling faster and less expensively: 1) preparing a larger volume of peel solution from each tube of Blue Peel base; 2) using higher concentrations of peel solution to reduce the number of coats necessary for reaching the desired depth of peel; and 3) storing the solution, as there is no need to adhere to the manufacturer's instructions to prepare the solution immediately before conducting the peel procedure to ensure homogeneity of the solution. The prepared solution can be stored at least 1 year.

Pruritic urticarial papules and plaques of pregnancy: polymorphic eruption of pregnancy (PUPPP)

The most commonly diagnosed pruritic dermatosis of pregnancy has a confusing nomenclature. The most commonly term used in the United States is pruritic urticarial papules and plaques of pregnancy (PUPPP), and in Great Britain, since 1982, polymorphic eruption of pregnancy. The etiology of PUPPP is still unknown. Placental products, hormonal alterations, and damage to connective tissue with subsequent conversion of nonantigenic molecules to antigenic ones, have been proposed as possible causes. The maternal and fetal prognosis is excellent. Treatment consists of topical or oral corticosteroids. Delivery does not usually provide relief of symptoms.

Life-threatening acute adverse cutaneous drug reactions

Adverse cutaneous reactions to drugs are frequent, affecting 2% to 3% of all hospitalized patients. Fortunately, only about 2% of adverse cutaneous reactions are severe and very few are fatal. Stevens-Johnson syndrome and toxic epidermal necrolysis are severe life-threatening diseases with a mortality rate reaching 30%, and only prompt recognition and diagnosis, withdrawal of the offensive drug, and referral to an intensive care unit or burn care unit might improve the prognosis and save the patient's life. Drug eruption with eosinophilia and systemic symptoms syndrome, formerly termed drug hypersensitivity syndrome, is a rather distinct severe adverse drug reaction (ADR) characterized by eruption, fever, lymph node enlargement, and single or multiple organ involvement, with a high morbidity and a mortality rate of 10%. These severe ADRs, together with serum sickness-like syndrome, are discussed in this review. Other severe reactions, such as anaphylaxis and vasculitis, are discussed elsewhere in this issue. Although most of the readers, particularly those in the outpatient arena, will not be treating these patients, they are the ones who will see them first, diagnose them, realize the potential danger in their condition, and refer them to the appropriate treatment venue. Therefore, dermatologists should be familiar with these conditions and be prepared to handle them adequately.

Autoinoculation and dissemination are two different forms of herpes virus spread

Autoinoculation and dissemination (or Kaposi's varicelliform eruption or eczema herpeticum) of herpetic lesions are two forms of viral spread, and it is essential to differentiate between the two. Presented are typical examples of the two forms of viral spread.

The myth of black henna

A 44-year-old woman presented with an eczematous, oozing eruption on her head, the back of her neck, and ears (Figure) that appeared one day after she had used a henna dye on her hair. She was aware of her allergy to permanent hair dyes, but her dermatologist approved of her use of natural dyes, such as henna. The dermatitis resolved within 1 week after she received an injection of combined betamethasone dipropionate 5 mg and betamethasone sodium phosphate 2 mg (Diprospan; Schering-Plough, Kenilworth, NJ).

"More is missed by not looking than by not knowing"[Thomas McCrae, 1870-1935]

CASE 1: A 19-year-old woman presented with a black crust on one part of the tattoo on her right leg (Fig. 1) which appeared after laser-assisted hair removal by an alexandrite laser (755 nm). CASE 2: A 28-year-old man underwent laser-assisted hair removal from his back and shoulders by an alexandrite laser (755 nm), after which he developed a burn on part of the tattoo on his right shoulder and was left with an atrophic scar (Fig. 2).

Drug rash with eosinophilia and systemic symptoms vs toxic epidermal necrolysis: the dilemma of classification

According to contemporary vernacular, when the cutaneous manifestations of drug rash with eosinophilia and systemic signs (DRESS) syndrome are those of Stevens-Johnson syndrome (SJS) or toxic epidermal necrolysis (TEN), the condition is defined as "DRESS syndrome with severe cutaneous reactions". In this article, we have presented arguments for and against including patients with skin lesions of the SJS/TEN syndromes who also have fever (practically all of the patients) and internal organ involvement (most of the patients) under the definition of DRESS syndrome. After weighing the arguments for and against this alteration of definition, we conclude that it makes more sense for patients with SJS/TEN to be classified as such and not be lumped together under the misleading label of DRESS syndrome.

Bacterial infections: uncommon presentations

The essence of dermatology is morphology. The most important instrument in the practice of dermatology has always been, and still is, the naked eye; however, "We see only what we are ready to see, what we have been taught to see" (Jean Martin Charcot). Although most practitioners will easily correctly diagnose common bacterial skin diseases (such as cellulitis, erysipelas, impetigo, etc), only a trained and updated dermatologist will recognize the unusual forms and rare variants of these diseases. Bacterial skin diseases are sometimes acute and life-threatening. The mortality rates from necrotizing fasciitis range from 20% to 40%, to name just one example. It is not unreasonable to expect that dermatologists, whether in clinical practice or in referral centers, will be the first physicians to be confronted with unusual variants of bacterial skin diseases that have been unrecognized by non-dermatologists. Some of these cases might even be life-threatening, and only prompt and early recognition, diagnosis, and treatment can make the difference between losing and saving a patient's life. In short, we dermatologists should hone our clinical diagnostic skills and expand our knowledge of the rare forms and unusual and atypical variants of skin diseases: the textbook variants will probably be recognized and treated by general practitioners.

Acne and diet

Forbidden foods? "The first law of dietetics seems to be: If it tastes good, it's bad for you" (Isaac Asimov, Russian-born biochemist and science fiction writer). This was essentially the Magna Carta for dermatologists of the 1950s: anything coveted by the teenage palate was suspect for morning after acne. Today, half a century later, although the slant has shifted away for this line of thinking in our dermatologic textbooks, several articles on the beliefs and perceptions of acne patients showed that nothing much has changed and that they expect us to give them detailed instructions of what "acne-related" foods they should avoid. In one such study(1), diet was the third most frequently implicated factor (after hormones and genetics) as the cause of the disease, with 32% of the respondents selecting diet as the main cause, and 44% thinking that foods aggravate acne. In another study that analyzed knowledge about causes of acne among English teenagers, 11% of the responders blamed greasy food as the main cause of the disease(2), whereas in another study found that 41% of final-year medical students of the University of Melbourne chose diet as an important factor of acne exacerbation on a final examination.(3)

The life-threatening complications of dermatologic therapies

Dermatologists use a variety of systemic drugs, some of which can cause severe adverse reactions and even fatalities. Ivermectin, a well-tolerated drug, can cause severe neurological side effects, whereas metronidazole, in high cumulative doses, has been associated with convulsions and rarely with hepatotoxicity. Dapsone is associated with frequent hematologic side effects, such as methemoglobinemia, hemolysis, and anemia. Although hepatotoxicity is rare and usually mild and reversible with the new antifungal agents, severe cutaneous reactions (such as toxic epidermal necrolysis, Stevens-Johnson syndrome, and anaphylaxis) have been reported. Even a relatively safe drug such as acyclovir has been reported to be the cause of renal failure and neurotoxicity. Retinoids can cause not so benign "benign" intracranial hypertension. Methotrexate can cause not only liver toxicity, but also myelosuppression and pancytopenia, which may be acute and life threatening. Nephrotoxicity is a well-recognized side effect of cyclosporine, whereas thrombotic thrombocytopenic purpura, which is associated with high morbidity and mortality, is less well known. Dermatologists should be familiar with these and other severe adverse reactions of the most popular and most used systemic medications of our trade.

Herpes simplex: autoinoculation versus dissemination

Autoinoculation and dissemination (or Kaposi's varicelliform eruption (KVE) or eczema herpeticum) of herpetic lesions are two forms of viral spread, and it is essential to differentiate the two. Autoinoculation means true infection with retrograde transport of the virus to the dorsal root ganglia of the relevant dermatome that allows the virus to remain there in a latent state for a lifetime, with periodic reactivation. Autoinoculation is, in a manner of speaking, a kind of self-infection with a virus that exists in the host. In contrast, KVE involves a spread of the lesions to the skin areas affected by another skin disease, but there is no true inoculation, i.e. the nerve endings and ganglion are not affected, and so reactivation and recurrences of these lesions will not usually occur. Four cases of autoinoculation and two of KVE illustrate the differences between these two forms of viral spread.

Ectoparasitic sexually transmitted diseases: Scabies and pediculosis

Scabies and pediculosis are diagnosed on an almost daily basis in many dermatology offices. Whether the patient seeks medical attention because of the often unbearable itch of scabies or because of the fear of lice infestations, the physician should be on the lookout for these ectoparasitic infestations. Secondary bacterial infection, resistance to medication, and the risk of spread of the infestations to family members and other close contacts may complicate the problem. Patients frequently have to battle the myths, prejudices, and even shame that are associated with such infestations.

Pemphigus vulgaris induced by radiotherapy

Pemphigus can be triggered or induced by many insults, such as drugs, infections, viruses and neoplasms. X-ray-induced pemphigus has been recorded only rarely in the literature. We describe the case of a woman with pemphigus vulgaris in remission, who relapsed 1 week after completion of an irradiation course for breast cancer, in the exact location of the radiation. We review the previous 15 cases from the literature and outline the common features of those cases.

Smoking can be good for you

Smoking is without doubt one of the greatest causes of avoidable illness and death in the modern world. Most well known is the relationship between smoking and numerous cancers, cerebrovascular and cardiovascular disease. Smoking and most especially nicotine, are, however, sometimes beneficial in certain diseases, including Parkinson's, Alzheimer's, allergic alveolitis, nausea and vomiting of pregnancy, pre-eclampsia, fibroids, carcinoma of body of uterus, ulcerative colitis, pyoderma gangrenosum, aphthous stomatitis and ulceration, pemphigus, herpes simplex and acne. In the immensely justifiable enthusiasm to discredit this dangerous activity, the mechanisms behind these beneficial effects tend to have been un-discussed or ignored. It is the aim of this paper to spur interest in the reasons for these effects. If the mechanisms are elucidated, therapeutic advances may be possible.

Cutaneous side effects of alternative therapy

Unconventional, complementary, and alternative therapies have become very popular forms of therapy and the predictions are that their popularity will continue to soar in the future. They are often perceived as being "natural" and therefore harmless, devoid of side effects, and without unpleasant consequences. The fact is that although their risks might be less than those of conventional drugs, side effects of this therapy can and do occur and must be considered as being a relevant factor in using such methods. It is to be expected that their numbers will increase in the future because of their growing popularity and because of continuing efforts to intensify their activity and therapeutic efficacy. Therefore, now more than ever, dermatologists should be familiar with all possible side effects, risks, and toxic, allergic, and possible mutagenic reactions. This article provides fundamental and vital information for practicing dermatologists.

Balneotherapy in dermatology

Balneotherapy and spa therapy emerged as an important treatment modality in the 1800s, first in Europe and then in the United States. Balneotherapy involves immersion of the patient in mineral water baths or pools. Today, water therapy is being practiced in many countries. Examples of unique and special places for balneotherapy are the Dead Sea in Israel, the Kangal hot spring in Turkey, and the Blue Lagoon in Iceland. Bathing in water with a high salt concentration is safe, effective, and pleasant for healing and recovery. This approach needs no chemicals or potentially harmful drugs. There are almost no side effects during and after treatment, and there is a very low risk to the patient's general health and well-being. Mineral waters and muds are commonly used for the treatment of various dermatologic conditions. The major dermatologic diseases that are frequently treated by balneotherapy with a high rate of success are psoriasis and atopic dermatitis. The mechanisms by which broad spectrums of diseases are alleviated by spa therapy have not been fully elucidated. They probably incorporate chemical, thermal, mechanical, and immunomodulatory effects. The major importance of balneotherapy and spa therapy both individually and as complements to other therapies lies in their potential effectiveness after standard medical treatments have failed to give comfort to these patients.

Still elusive relationship between atopic dermatitis and allergic contact dermatitis

The relationship between atopic dermatitis (AD) and allergic contact dermatitis (ACD) has long been and continues to be an unsolved and frequently discussed issue. Whereas AD patients have traditionally been considered to have a decreased frequency of ACD, recent studies revealed that these individuals are more or equally likely to develop ACD. The aim of the present review was to determine whether the results of recent experimental studies and theoretical considerations might lead to a parallel shift in our concept on the causal relationship between AD and ACD. It has been shown that Th2 and Th1-type immune responses are not mutually exclusive, and that at least in AD a mixture of both Th2 and Th1 occurs and the interactions between them account for the clinical characteristics of the disease. This new concept on the immunopathomechanism of AD challenges our previous belief that the cytokine pattern of the affected skin is unsuitable for the development of delayed-type hypersensitivity. Since we do not know the exact quantitative balance between Th1 and Th2 reactions along a time axis, we cannot predict whether the cytokine pattern of AD patients favors or inhibits the development of ACD. What we do know with a greater degree of certainty, is that when the eczematous excoriated skin of AD patients, with its defective epidermal barrier (enhancing the penetration of many antigenic substances) is chronically exposed to skin care products and various sensitizing topical medications, it is more likely to develop a superimposed ACD.

Cafe au lait has hue of its own

Segmental pigmentation disorder is a pigmentation disorder (hypo- or hyperpigmentation) first described some 20 years ago. It appears early in life, is segmental, and usually has a sharp border in the midline. It can be confused clinically and histologically with several pigmentary disorders, especially with giant or segmental cafe-au-lait macules. The purpose of this article is to promote, revive, and refresh this somewhat neglected entity, and to further subdivide it into two types: segmental pigmentation disorder simplex and segmental cafe-au-lait. We illustrate our contention with case reports.

Sunscreens--the ultimate cosmetic

One decade ago, a sun protection factor (SPF) of 15 was considered a complete blocker of ultraviolet radiation (UV). The logic behind that cutoff point was that sunscreens with this SPF number would always prevent erythema and that preventing erythema would prevent all the ill effects of UV exposure. Today, we know that both of these assumptions were wrong and we tend to recommend higher SPF. Consumers apply only about one-quarter to one-half thickness of the layer of sunscreen material used to measure the SPF in the laboratory. That means that less than 50% of the SPF number claimed on the label is spread on the consumer's skin, meaning that a sunscreen with an SPF 30 will give the real protection of an SPF of 15. Therefore, recommend 60 when you want a real protection of 30! Significant injury, DNA damage, mutations, and carcinogenesis can and do occur also with cumulative suberythemal UV exposure. Thus, erythema induction, a criterion that defines SPF, is not a good indicator of UV damage. We also need higher SPF values to prevent the damage caused by suberythemal doses of UV. The value of the SPF claimed on the label is diminished by environmental factors that are not taken into account during SPF measurements in the laboratory, such as sweating, water immersion, rubbing off, and photodegradation. There are some misunderstandings and confusion about the mode of action of physical sunscreens. It was originally considered that, in contrast to organic sunscreens, the inorganic metal oxides (zinc oxide and titanium dioxide) acted as scatterers or reflectors of UV light, as a mirror. This is not the case with modern micronized forms of metal oxides. It has been shown that both zinc oxide and titanium dioxide mobilize electrons within their atomic structure while absorbing UV radiation. Thus, although metallic oxides are not inert per se, in their coated form they are stable, non-toxic, and safe and they act as highly efficient UV attenuators. Therefore, we recommend our patients to use this type of sunscreens. We should exert all our influence upon our patients not to expose themselves to excessive sunlight, to routinely use generous layers of sunscreen agents, and to wear protective clothing. To wait for the dust to settle around the issue of the effectiveness of sunscreens in preventing melanoma, while the ideal sunscreens--topical, systemic, whatever--are at our disposal, is a luxury we cannot afford.

Along these lines

Non-melanotic discoloration of the skin can result from the accumulation of various internal agents (ingestion, inhalation, or injection), chemicals or drugs, such as heavy metals, amiodarone, tetracycline, clofazimine and others, or exogenous (topical) substances. Identifying the causative agent frequently requires a thorough investigation and clever detective work, including visits to the home and workplace. It is, however, rare that the patient presents at a clinic with the corpus delicti, and it is even more rare when neither the patient nor the treating physician are initially aware of it. "What is the hardest of all? That which you hold the most simple; seeing with your own eyes what is spread out before you."[J.W. Goethe quoted by J.P. Eckermann in Converstions with Goethe, May 18, 1824.]

Co-existing sensitivity to metronidazole and isothiazolinone

A 68-year-old woman developed allergic contact dermatitis to topical metronidazole gel as proven by positive patch tests to the gel and to metronidazole. She was also allergic to methylchloroisothiazolinone and methylisothiazolinone (MC/MI). The similarity between the two molecules and the fact that the patient reacted to the gel after the very short incubation period of 1 day (i.e. not long enough for acquiring an active sensitization) makes the possibility of a cross-reaction between these substances very plausible. As the isothiazolinones are widely used and comprise an important and relatively frequent cause of allergic contact dermatitis, a cross-reactivity with metronidazole means that perhaps there should have been more cases of metronidazole allergy is more common than the current literature suggests.