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Y Har-Shai

Publications and source records attributed to Y Har-Shai.

At least 19 recordsLinked to original sources
PubMed2005

Electrical impedance scanning for melanoma diagnosis: a validation study.

BACKGROUND: A multicenter study was conducted to test the ability of electrical impedance scanning to differentiate between benign and malignant skin lesions. The performance of a dual electrical impedance scanning/image analysis device was also assessed. METHODS: Electrical impedance scanning measurements of 449 preoperative lesions found on 382 patients and including 53 melanomas from the trunk and extremities were performed. Results were correlated with histopathologic findings. In addition, ABCD parameters for the lesions were automatically calculated by the system. RESULTS: Electrical impedance scanning detected melanomas of the trunk and extremities with 91 percent sensitivity and 64 percent specificity. Moreover, sensitivity of electrical impedance scanning was increased to 100 percent for in situ and thin melanomas of smaller size (n = 27). Visual examination identified as malignant only 67 percent of these early tumors (p = 0.002). Clinical examination detected 96 percent of the larger or thicker melanomas (n = 26), whereas electrical impedance scanning detected only 81 percent of them. Combined electrical impedance scanning and image analysis detected 100 percent of the melanomas, independent of their thickness, and with no significant decrease of specificity. Because of electrical differences between the head/neck and the rest of the body, the assessed electrical impedance scanning parameters were not adequate for the diagnosis of melanomas from the head and neck. CONCLUSIONS: A validation study proved the value of electrical impedance scanning as a noninvasive technique for detection of melanoma lesions of the trunk and extremities, specifically, of in situ and thin type. In addition, image analysis was shown to be a valuable, complementary procedure. New parameters should be designed to optimize the performance of electrical impedance scanning for melanomas of the head and neck.

Adult↗
PubMed2004

Evaluation of penile revascularization for erectile dysfunction: a 10-year follow-up.

The objective of this study was to report long-term success rates for penile revascularization (PR) and investigate factors responsible for failures. During the past 10 y, data were obtained on 52 patients who underwent PR. Surgical technique was selected according to preoperative arteriographic findings. The mean age was 28.5 y and the mean follow-up was 70.8 months. Success was defined as satisfactory intercourse without additional therapy. Overall success was 48%. Patients under 28 y showed a 73% success rate vs 23% in the older ones (P=0.0003). Nonsmokers had a 57% success compared to 29% in smokers (P=0.05). The presence of venous leak and type of procedure had an insignificant impact on success (P=0.33 and 0.23 respectively). To conclude, this curative treatment option is limited to a selective population with vasculogenic erectile dysfunction. We found that the cure rate of this procedure is maintained and long-term follow-up shows good results, especially in the young nonsmokers.

Adult↗
PubMed2003

Pilot study of a novel treatment for androgenetic alopecia using enriched cell culture medium: clinical trials.

Androgenetic Alopecia (AA) afflicts a large part of the population and of the many treatments available today none is completely satisfactory. Testing the efficacy and safety of a novel topical treatment for AA which is based on cell culture medium supplemented with insulin, thyroxin and growth hormone (CCM). The 48 participants classified as androgenetic alopecia Type II, III or IV on the Hamilton scale, concluded a randomized, vehicle-controlled, double-blind trial of 6 months duration. Under occlusive cover the gel was self applied for at least 3 hours daily. Evaluation was based on hair counts, investigator global assessment and participants self-administered questionnaire. Cessation of hair loss was reported by most participants within 28 weeks, and further confirmed by the hair count (HC) in ~80% of participants. Moreover, as early as 4 months after the start of the treatment, a time dependent increase of up to 50% in HC was observed. The average change in HC between the two groups differed significantly (p=0.007), with values of 4.1% for control and 13.8% for CCM. Following 4 months of treatment, a time dependent increase in HC (>10%) above minimal was observed in 55% of the CCM and 25% of the control and this trend continued. At 6 months 63% of the CCM and 33% of the control group exhibited increase of HC higher than 10%. The average increase in HC in the CCM and the control groups was 17.1% and 8.9% respectively (p=0.035). Self evaluation questionnaires revealed a time dependent increase in satisfaction in the CCMusers compared to the control. While the average score at T2 was similar in CCM and control (2.7 and 2.6 respectively), the score at T6 in the CCM increased to 5.9 and decreased to -0.4 in the control (p=0.007). Global-clinical evaluation following six months treatment revealed significantly (p=0.02) more hair loss in the control group (40%) compared to the CCM (7%) treated group. CCM was found effective in treating androgenetic alopecia in men. It induced cessation of hair loss, increased rate of hair growth and appearance of new hair. No side effects were reported or observed.

Administration, Topical↗
PubMed2001

Distal arteriovenous fistula to maintain patency of the venous drainage of a latissimus dorsi flap following subclavian vein repair.

Successful reconstructive surgery with muscle flaps depends on adequate arterial supply and undisturbed venous drainage. Combining such surgery with reconstructive vascular surgery of a large-caliber vein that is responsible for the venous drainage of the flap poses an additional challenge--the repaired vein's susceptibility to thrombosis. Every attempt must be made to prevent venous outflow obstruction following muscle flap surgery. Data from the vascular surgery literature demonstrate a low success rate for subclavian vein repair. The success rate with venous reconstructive surgery has been greater when a distal arteriovenous fistula accompanied the repair. The present case described the use of a temporary distal cephalic-brachial arteriovenous fistula to maintain the patency of the venous drainage of a pedicled latissimus dorsi muscle flap, following subclavian vein repair, for one-stage coverage of a large chest wall defect.

Adenoma, Sweat Gland↗
PubMed2001

Sensitivity and positive predictive values of presurgical clinical diagnosis of excised benign and malignant skin tumors: a prospective study of 835 lesions in 778 patients.

This article reports on the sensitivity and positive predictive value of clinical diagnosis of benign and malignant skin tumors by expert plastic surgeons in an Israeli clinic. Most published reports have focused on the sensitivity of clinicians' diagnoses, a general measure of the physician's skill that does not predict the rate of accuracy of a physician's diagnoses. Our study of 835 lesions in 778 patients, one of the largest Israeli series, assesses the clinical diagnosis of malignant and benign skin tumors and is one of the few that provide information on the positive predictive value, the measure that is of interest to both physicians and patients. The majority of tumors were benign (56.8 percent), 31.6 percent were malignant, and 11.6 percent were premalignant. Among the 474 benign lesions, 46 percent were nevi. The most common nevi subclass was compound nevi (53 percent), 9 percent of the nevi were dysplastic, and 5 percent were blue nevi. The most common malignant tumor was basal cell carcinoma, accounting for 78 percent of malignant tumors. Although sensitivity for clinical diagnosis of malignancy was 91.3 percent, the positive predictive value for clinical diagnosis of malignancy was 71.3 percent. The sensitivity rate for clinically diagnosing premalignant tumors was 42.3 percent, whereas the positive predictive value for these diagnoses was higher (64.1 percent). The sensitivity rate for diagnosis of all benign lesions was 85.9 percent, and the positive predictive value was 94.2 percent. The sensitivity rate for diagnosis of all nevi was 87.6 percent, and the positive predictive value was 85.7 percent: i.e., only seven of the 218 pathologically proven diagnoses of nevi (3.2 percent) were falsely diagnosed as malignant lesions. Even more interestingly, five of the 223 clinical diagnoses of nevi (2.2 percent) were pathologically proven to be malignant melanomas, and seven were found to be premalignant lesions (3.1 percent). It was concluded that publications which report only on the sensitivity neglect to provide information of interest regarding the positive predictive value. Often, positive predictive value is qualitatively different from the sensitivity, and thus relying only on the sensitivity may lead to incorrect evaluation of a clinical judgment, which may result in erroneous surgical decisions.

Adolescent↗
PubMed1999

Striae distensae of augmented breasts after oral contraceptive therapy.

A case of striae distensae (SD) of bilateral augmented breasts following oral contraceptive therapy is presented. Striae maturation and the prevention of additional skin marks was achieved with immediate cessation of oral contraceptive pill therapy and long-term daily topical application of tretinoin cream. It is suggested that patients who are candidates for breast augmentation surgery should be informed of the possible risk of developing SD if they are taking or planning to take the contraceptive pill.

Adolescent↗
PubMed1999

An integrated approach for increasing the survival of autologous fat grafts in the treatment of contour defects.

Autologous fat grafting as a technique to correct soft-tissue defects is a controversial subject. The high percentage of fat resorption and the resulting need for additional grafting considerably reduce the value of this method. The purpose of this study was to evaluate the clinical application of tissue-culturing methodology in the handling of the lipocyte aspirate in an endeavor to improve the survival rate and therefore the take of the grafted lipocytes. The method consists of syringe aspiration of the lipocytes from the donor site, isolation of intact lipocytes by gentle centrifugation, suspension of the aspirate in an enriched cell culture medium, and injection of the cell suspension into preformed subdermal tunnels. A number of media were tested and shown to prolong the survival of lipocytes ex vivo using fluorescent acridine orange stain. Implementing the integrated cell culture techniques increased the lipocytes' viability, as indicated in clinical evaluation in which the amount of graft take ranged between 50 and 90 percent. The results of 15 patients with varied types of cases who were operated on using this new methodology show that the tissue defect was filled and remained so in postoperative follow-ups of 6 to 24 months. A three-dimensional CAT scan-aided evaluation method was developed and used in one of four case histories presented herein.

Adipose Tissue↗
PubMed1999

Improved vitality of experimental random dorsal skin flaps in rats treated with enriched cell culture medium.

A defined, serum-free cell culture medium supplemented with nonsteroidal anabolic hormones, insulin, thyroxin, and growth hormone was found to accelerate wound healing by stimulating vascularized granulation tissue formation, epithelialization, and angiogenesis. The aim of this work was to study the effect of cell culture medium on the survival rate of cephalically based random dorsal skin flaps in an animal model. A total of 77 Sprague-Dawley rats were randomized into five treatment groups: pharmacologic delay with cell culture medium, flap enhancement with cell culture medium, surgical delay, biological delay with saline, and control. Statistically significant differences in distal flap necrosis were found among all groups (p<0.003). The rats treated with cell culture medium before flap elevation showed a significant increase in flap viability: a survival rate of 83 percent, compared with the control group, which demonstrated a survival rate of only 58 percent (p<0.0001). The surgical delay and the groups treated with cell culture medium yielded similar results with no significant difference between them. This study indicates that preoperative injection of cell culture medium may play a role in decreasing skin flap necrosis.

Animals↗
PubMed1998

Partial breast necrosis after MIDCABG via small anterolateral thoracotomy.

We report a case in which partial breast necrosis developed after minimally invasive direct coronary artery bypass grafting using an IMA Retractor (Cardio-Thoracic Systems Inc, Cupertino, CA). We suggest that during minimally invasive direct coronary artery bypass grafting in the presence of a large breast, it is advisable to reduce the intraoperative additive forces of pressure and traction caused by the retractor arm on the breast tissue, thus avoiding further excessive compression on the partially compromised blood circulation of the breast.

Breast↗
PubMed1998

Static-electric field induction by a silicone cushion for the treatment of hypertrophic and keloid scars.

Silicone gel and silicone occlusive sheeting are widely used at present for the treatment of hypertrophic and keloid scars, without any scientific explanation as to their mode of action. In a recent paper the possibility was raised that static electricity generated by friction-activated silicone sheeting could be the reason for this effect, and that it can, with time, cause involution of hypertrophic and keloid scars. The objective of this study was to test this hypothesis and to observe whether a continuous and also an increased negatively charged static-electric field will shorten the treatment period. A device to implement these requirements gradually evolved over a 5-year period. A number of prototypes were tested until the final product was attained. Some of the patients in this study were treated initially with a silicone sponge inserted in the cushion. Later this version was changed to the final design described herein. A silicone cushion was developed with the purpose of increasing a negative static-electric charge to accelerate the regression process. The cushion is custom-made using a silicone occlusive sheeting envelope of 0.75-mm thickness, which does not deteriorate with use, and is partially filled with high viscosity silicone oil. Its edges are sealed, and its size is designed to extend a little beyond the scarred area. Static electricity readings, generated by activating the cushion by pumping action with the fingers, stretching or deforming the cushion, are invariably much higher when compared with those obtained with silicone occlusive sheeting and silicone gel sheeting. The interaction between the negatively charged ions of the cushion and the ionic charges of the tissue fluids may be the critical factor in achieving hypertrophic and keloid scars involution. Of the 30 patients enrolled in the study, 3 patients dropped out. Treatment with the silicone cushions yielded 63.3 percent cessation of itching and burning followed by pallor and flattening of the scar, some markedly so, over a few weeks to 6-month period. An additional 26.6 percent had their scars resolved in up to 12 months of treatment. Good contact of the cushion over the scar has been shown to be important in this clinical trial, and much creativity is needed for making elastic strap bindings that ensure this contact. The clinical trials extended over a 12-month period. Ten patients (33.3 percent) who had recalcitrant scars with little response to the use of the silicone cushion were given intralesional corticosteroid injections, in addition to the continued use of the cushion, resulting in a fairly rapid resolution of these scars over a period of months to a year.

Adolescent↗
PubMed1998

Computerized morphometric quantitation of elastin and collagen in SMAS and facial skin and the possible role of fat cells in SMAS viscoelastic properties.

Recently, the superficial musculoaponeurotic system (SMAS) was found to be a composite tissue comprising collagen, elastic fibers, and fat cells in an extracellular viscous matrix. Both SMAS and facial skin tissues exhibit viscoelastic properties, but SMAS tissue has delayed stress relaxation. As a consequence, SMAS is viewed as a firmer elastic foundation for the more viscous facial skin. In some patients, a slackening effect of SMAS tissue takes place over a period ranging from weeks to months after tightening. To determine the relative quantity of viscoelastic components and better understand their biomechanical behavior, a quantitative morphometric study of the elastic and collagen fibers in the SMAS and facial skin was conducted. Thirty-four SMAS preparations were taken from 17 patients during either primary face lift operations (12 women) or reoperative face lift procedures (4 women, 1 man), which were performed 4 to 9 months after the original surgery, to examine the elastin and collagen content. For comparison, preauricular skin was also gathered from these patients. The specimens were stained with Weigert's staining to identify elastin and collagen fibers. Using a computerized morphometric analysis, 100 fields of each SMAS and skin specimen were examined. According to our findings, the average percentage of elastin and collagen fibers in SMAS and facial skin was as follows: (1) the percentage of elastin fibers in the SMAS was 4.71 +/- 1.2 (standard error of mean +/- 0.0291); (2) the percentage of elastin fibers in the skin was 6.1 +/- 1.8 (standard error of mean +/- 0.0436); (3) The percentage of collagen fibers in the SMAS was 38.7 +/- 5.9 (standard error of mean +/- 0.1430); and (4) the percentage of collagen fibers in the skin was 48.47 +/- 6.96 (standard error of mean +/- 0.1688). A statistical significance of p < 0.0001 was demonstrated between the collagen and elastin groups. A different percentage of elastin and collagen fibers was found among the 17 patients and within each of them separately. Neither gender nor age differences were found regarding elastin and collagen fiber content. No statistical differences were demonstrated between specimen sources, i.e., whether the operations were primary or reoperative face lift procedures. Findings from previous studies indicate that the cheek has two viscoelastic layers, the skin and the SMAS. The proportional similarity in average percentages of elastin and collagen in SMAS and facial skin cannot explain the relatively delayed stress relaxation effect of the SMAS. Therefore, the fat cells that are found exclusively in the SMAS probably lend a certain degree of firmness to this layer and play a significant role in the long-term efficacy of SMAS surgery.

Adipocytes↗
PubMed1997

The surgical anatomy of the fat in the upper eyelid medial compartment.

The surgical anatomy of the upper eyelid fat in the medial compartment was investigated in 388 patients and in 12 cadavers. We found two individual fat pads comprising this compartment. The difference among the investigated cases was found to be the extent of their separation. In 16.7 percent of the cadavers' eyelids the fat pads were entirely separated, in 45.8 percent they were separated to about half their length, while in 37.5 percent only the tips were separated. Among the patients in whom only the protruded fat was inspected, 59.8 percent of the fat pads were separated, and in the rest, only the tips were isolated. On histologic examination we could always identify two well-circumscribed fat pads, each surrounded by a fibrocollagenous tissue. At the level of their interconnection, a loose fibroareolar tissue was found. In practice, during blepharoplasty, both fat pads should be addressed in order to achieve the expected results.

Adipose Tissue↗
PubMed1997

Aesthetic results and patient satisfaction with immediate breast reconstruction using tissue expansion: a follow-up study.

Immediate breast reconstruction with the tissue expander is now established as an accepted procedure after mastectomy, and large series have been published concerning the technique and its complications. Unfortunately, only scarce information is available regarding the long-term aesthetic results and patient satisfaction achieved by immediate reconstruction using tissue expansion. In this study, we reviewed 52 patients who had undergone immediate breast reconstruction using the tissue expander with a follow-up of at least 1 year after completion of the reconstruction. We developed an objective assessment of patient satisfaction, aesthetic results, and the factors affecting them. The results show remarkable concordance of assessment by patient, surgeon, and independent observer: All gave good scores for aesthetic appearance (6.4 to 7.4 on a scale of 1 to 10). A total of 92.3 percent of patients rated their satisfaction as good to excellent. Symmetry was the main parameter influencing the patients' score, while the surgeon's score also was affected by the quality of the inframammary fold and capsular contracture. Breast size, chemotherapy, complications, time interval, and additional procedures had no relation to either scoring or patient satisfaction.

Breast Neoplasms↗