Bernard Hirshowitz

A skin-stretching device for the harnessing of the viscoelastic properties of skin

A skin-stretching device that is designed to harness the viscoelastic properties of the skin using incremental traction is presented as an addition to the surgeons armamentarium. It has proved to be of value in helping to close problematic areas of skin shortage which would otherwise have required more complicated procedures for their solution. It is simple in application and can even be put to use at the bedside. It consists of two pins that are threaded through the dermis of the wound margins on either side of the defect and which are in turn engaged by the hooks of the stretching device. The stretching force on the skin margins is spread over a wide area, thus preventing damage to the skin itself that individual hooks applied to the skin might cause. The device is employed over a duration of 20 to 30 minutes to 1 to 3 days depending on the condition of the skin adjoining the defect. The device can be applied over three different periods of time: (1) preoperatively (presuturing), lasting 1 to 2 days, (2) intraoperatively, extending over a period of 20 to 30 minutes, and (3) postoperatively (or delayed), which takes place over a time span of hours to 1 to 3 days. Five illustrative cases are presented.

Free-fat injections for the correction of hemifacial atrophy.

Three adult patients with long-standing hemifacial atrophy were treated with repeated free-fat injections at 4- to 8-week intervals. The longest follow-up study to date is 18 months, and following the expected postoperative resorption, no further loss of bulk of injected fat has been observed. On palpation, the feel of the fat is normal, and facial expression is also good. The relative ease of this procedure, which does not entail any scarring, appears to justify more widespread use of free-fat injections to restore facial soft-tissue depressions.

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

&NA; 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. (Plast. Reconstr. Surg. 101: 1173, 1998.)

Mechanical properties and microstructure of the superficial musculoaponeurotic system.

Because of the widespread reliance on SMAS tightening procedures in present-day face lift surgery, a study was undertaken to examine the physical properties and microscopic structure of both virginal (40 specimens) and reoperated (8 specimens) SMAS tissue. The findings could be of practical value to the surgeon and are reported herewith: First, the SMAS is a composite fibrofatty layer comprising collagen and elastic fibers interspersed with fat cells. Second, microscopic appearance shows a considerable amount of elastic fibers in close relationship to the collagen fibers. Third, on scanning electron microscopy, the collagen fibers in the virginal SMAS show a convoluted appearance similar to that found in the dermis. In the reexcised SMAS tissue, there is some evidence of parallelization of the collagen fibers as seen in the stretched dermis. Fourth, mechanical testing (Instron), i.e., a series of loading/unloading tests at various rates and amplitudes, and stress relaxation tests were performed on samples of preauricular skin and SMAS. These indicated definite viscoelastic properties for both sets of specimens, with the tendency of an increased stiffness and a reduction in viscoelastic effects on repeated working of the samples. Overall, the mechanical behavior of both tissues was somewhat similar, the viscoelastic effects in SMAS being less pronounced. A nonlinear viscoelastic model is under development to represent the behavior of both tissues. The implications of these results may help to explain the slackening effect observed in some postoperative patients.

Treatment of keloid scars by combined cryosurgery and intralesional corticosteroids

Fifty-eight patients with keloid scars were subjected to combined cryosurgery and intralesional corticosteroid therapy. Complete regression of the scars occurred in 41 patients. In 8 patients the scars improved, and there was no improvement in 9 patients. Keloid scars of the earlobes were the most responsive to treatment.The possibility of differing biological activity of cryosurgery and corticosteroids complementing each other is postulated, and a combination of their respective actions may offer promise in treatment.

Bilateral superomedial thigh flaps for primary reconstruction of scrotum and vulva.

The use of bilateral superomedial thigh flaps for primary reconstruction of scrotum and vulva is presented. These flaps have proved to be reliable, ensuring good healing and providing almost normal sensation. Further indirect evidence that these are arterial flaps is given.

Large liponecrotic pseudocyst formation following cheek augmentation by fat injection

A case in which a growing cystic mass developed in the submandibular area, 6 months following fat injection to the cheek and mandibular area, is described. Histological examination revealed a liponecrotic pseudocyst. It is suggested that subcutaneous masses appearing in an area, which was previously injected with fat, should be excised. Diagnostic aspiration procedures may cause leakage of its oily content and possible further granulomatotic reactions and cysts.

One-stage reconstruction of the scrotum following Fournier's syndrome using a probable arterial flap.

A one-stage procedure is described for restoring the scrotum in a patient who suffered from Fourniers gangrene. The proximal superiomedial-based thigh flaps employed are most likely arterial flaps. These flaps are also well innervated, which makes them ideal for the purpose of scrotal reconstruction.

Viscoelastic Properties of the Superficial Musculoaponeurotic System (SMAS): A Microscopic and Mechanical Study

Abstract. A study was undertaken to determine the physical properties and microscopic structure of the superficial musculoaponeurotic system (SMAS) tissue. Forty virginal specimens and eight reoperated specimens were examined. The following findings were discovered. 1) Microscopic appearance shows the SMAS to consist of collagen fibers, a relatively high concentration of elastic fibers interspersed with fat cells. 2) On scanning electron microscopy, the virginal SMAS shows the collagen fibers to have a similar convoluted appearance as in the dermis. There is some evidence of parallelization of the collagen fibers in the reexcised SMAS specimens. 3) Mechanical testing (Instron) demonstrates that both the SMAS and preauricular skin were subjected to a series of loading/unloading tests at various rates, amplitudes, and stress relaxation tests. Both sets of specimens indicated definite viscoelastic properties. Although the mechanical behavior of both tissues was somewhat similar, the viscoelastic effect of the SMAS was less pronounced. A slackening effect of the SMAS indicated a gradual expansion of the SMAS postoperatively. These results could provide some indication of the long-term effects of SMAS surgery.

Treatment of hemangiomas by sclerosing agents: an experimental and clinical study.

Twenty-one patients with hemangiomas on the face and lip who were treated with injections of sclerosing agents are discussed. The mode of action of these drugs was also studied experimentally on rats, which were injected through the pampiniform plexus of the spermatic cord. In the clinical study all patients showed satisfactory resolution of the hemangiomas with commensurate improvement in their appearance. The experimental study provides an explanation for the replacement of blood vessels by young connective tissue.