Ann. Medit. Burns Club - vol. V11 - n. 4 - December 1994

PRESSURE THERAPY IN THE TREATMENT OF ADVANCED POST-BURN HYPERTROPHIC SCAR: A COMPARATIVE STUDY OF CLINICAL EVALUATION, PHOTOGRAPHY AND ULTRASONOGRAPHY

Kaya L*, Kivang K*, Dalay W, AcartOrk S.*, Atila E**

* Division of Plastic Surgery, University of Qukurova Medical School, Adana, Turkey
** Division of Diagnostic Radiology

SUMMARY. Eleven bum patients are presented who were treated with pressure garments. The changes in hyper-trophic scar thickness were followed by means of clinical evaluation, photography and high-resolution ultrasonography (USG) in our Bum Unit in 1990-1993. Patients were selected from those who had palpable scars and were late for pressure treatment. The custom-made pressure garments (JuzoHelastic Cotton, Germany) were worn by the patients for about eight weeks after the burn wound had healed. Changes in scar thickness were measured by ultrasonography before treatment and at three-monthly intervals during pressure therapy. We concluded that pressure treatment can control advanced scars that were late for treatment. Changes in scar thickness can be objectively demonstrated better by USG than by clinical evaluation and photography.

Hypertrophic scars are frequent sequelae of burn injuries. This condition can be prevented and controlled by means of pressure garments, the pressure of which can be controlled (1, 2, 3, 4).
Pressure treatment is usually performed by applying an elastic garment to the surface of the scar. The general view is that pressure treatment should be applied early -preferably two weeks after healing of the burn wound and the skin-graft areas. It has been suggested that the garments should be worn 24 hours a day except for short periods for hygienic purposes. The treatment should be continued for at least nine months and if scarring recurs, it is necessary to resume treatment. For effective treatment, a pressure ranging from 18.4 to 32.2 mm Hg should be applied (1, 5).
The many methods for following the progress or maturation of a scar include scar elastometry, negative imaging, photography, biopsy and clinical evaluation (6). Highresolution ultrasonic scanning is also used as an objective method for detecting skin lesion and measuring the scar thickness quantitatively (7).
In our study, palpable hypertrophic scarred post-bum patients who were late for pressure treatment were treated with pressure garments and the results of treatment were followed by clinical evaluation, photography and USG. The above parameters were also compared with each other and the results were evaluated.

The group in this study consisted of 11 patients treated in the Burn Unit at the University of ukorova Medical School between 1990 and 1993. The patients' mean age was 21 years (range, 7-59) and the mean body surface area burned was 23%.
The pressure garments were custom-made (JuzoHelastic Cotton, model 3021, compression class 1). The garments were worn by patients who were late for pressure treatment for about eight weeks after the bum wound and the skin-graft area had healed. The patients wore the garments 24 hours a day, except for hygienic needs, and treatment continued for about nine months.
The patients were examined clinically every month. During clinical evaluation, photographs were taken every three months (Cannon EOS 10 camera with a 50 mm macrolens) and scar thickness was measured by USG (GE RT 4000 Real Time Duplex Scanner).
A test scar was chosen to evaluate the results of treatment and the distances of this scar from anatomical landmarks were recorded. Clinical evaluation, photography and USG of the same scar were repeated every three months. The scar was clinically graded from 0-2, according to the findings of itchiness and firmness. After photographic evaluation the scar was measured by ultrasonography and the results obtained were evaluated in millimetres. This procedure was performed at a frequency of 5.0-7.5 megahertz, and the microview transducer which functioned as both sender and receiver of sound and a small gel bath were enclosed in a plastic membrane.

Ultrasonic scanning shows hypertrophic scarring as an area between two hypodense lines (Fig. 1). Before initiation of pressure treatment, USG was used to measure the scar thickness of patient #7, which was 6 mm. At this time patient #7 was grade 2, and grade 2 by clinical and photographic evaluation (Fig.2).

Fig. 1 - Ultrasonic scan showing hypertrophic scarring as an area between two hypodense lines.

Fig. 2 (a) - Photographic evaluation of patient #7 before pressure treatment. Fig. 2 (b) - Ultrasonic evaluation of patient # 7 before pressure treatment.

Fig. 3 (a) - Photographic evaluation of patient #7 after three months of pressure therapy. Fig. 3 (b) - Photographic evaluation of patient #7 after three months of pressure therapy. Fig. 3 (c) - Ultrasonic evaluation of patient #7 after three months of pressure therapy.

Fig. 4 (a) - Photographic evaluation showing results of pressure treatment in ninth month. Fig. 4 (b) - Ultrasonic evaluation showing results of pressure treatment in ninth month.

US: Ultrasonography (sear thickness in mm) CE: Clinical evaluation (scale, 0-2: itchiness and firmness0; firmness (+) = 1; itchiness and firmness (+) = 2 PH: Photography (scale, 0-2: blistering and redness 0; blistering (+) = 1; blistering and redness (+) = 2
thickness as measured by USG performed three months after pressure treatment was 4 mm and at the same time clinical and photographic evaluation both gave grade 2 (Fig.3). Ultrasonic scanning after nine months measured scar thickness as 2.0 mm, while the clinical evaluation was grade 1, as also the photographic evaluation (Fig.4). When the parametric findings obtained from this patient were presented in a graph (Fig.5), it could be objectively seen that there was a clear change in scar thickness on USG evaluation, whiIQ there was only slight change in the clinical and photographic evaluations, in the 6-9 month period.

Fig. 5 - Graphic display of ultrasonically measured scar thickness, photography and clinical evaluations in patient #7 in whom pressure therapy was initiated at three-monthly intervals.

The findings obtained from the study group were tabulated (Table I). Before pressure treatment was initiated, the scar thickness of all the patients was grade 2. It was also grade 2 by clinical and photographic evaluation and measured 2.2-6.0 ram by ultrasonic scanning. In the ninth month of pressure treatment, the scar thickness of eight of the patients who were clinically regarded as grade 0 was grade 1 on photographic evaluation and measured 1.0 trun on USG evaluation. These patients showed good clinical response, while the other patients fared poorly.

Hypertrophic scars characteristically form within the first six to eight weeks after epithelialization occurs. During the subsequent "maturation" process, which lasts two or more years, partial or complete resolutibn typically occurs. The pressure treatment used for post-bum hypertrophic scarring is regarded as a non-invasive method. Pressure garments not only prevent and control scarring but also regress advanced scarring. Use of the garments improves hypertrophic scar formation by increasing the hypoxic condition, which results in focal degeneration of selective cells. The exact level of effective external pressure, though usually taken as being approximately that of arterial capillary pressure (24 mm Hg), has not been scientifically demonstrated (1).
In this study group we applied a pressure range of 18 to 32.2 turn Hg. Analysis of the patients showed a good clinical response in 72.7% of the cases and a poor response in the others. These rates are consistent with those of previous studies (1, 4, 8).
It is clinically important to determine scarring and regression objectively in clinically objective terms. For this purpose photography and ultraphonographic scanning are used (9).
In our study, we were able to measure objectively the full thickness of scarring by means of USG. With other methods, it is not possible to measure scar thickness objectively. Measurement of scar thickness by USG is a simple method, and as it is easily tolerated by the patients it is useful during other scannings. Another advantage is that it measures completely both the visible and the invisible sides of the scar. To eliminate measurement errors, the highest and the lowest measurements should be determined and the mean calculated for the evaluation.
The clinical progress or maturation of the scarring can be evaluated by means of clinical evaluation and photography. Small changes in scarring may not be evaluated by these parameters. Normally, in the treatment protocol, there are no objective methods for comparing scarring changes.
We have found that very good results can be obtained by pressure garments in advanced post-burn scars. We followed the results of our treatment protocol by scanning scar thickness. In our opinion, high-resolution ultrasonic scanning is a simple, noninvasive and objective method for demonstrating changes in scar thickness.

RESUME. Les auteurs présentent onze patients brûlés traités avec les vêtements compressifs. Les modifications de l'épaisseur des cicatrices hypertrophiques ont été suivies par l'évaluation clinique, la photographie et le balayage ultrasonique (USG) à haute résolution dans notre Service de Brûlures dans les années 1990-1993. Les patients ont été sélectionnés entre ceux qui avaient des cicatrices palpables et étaient en retard pour le traitement de pression. Les vêtements compressifs faits sur mesure (Juzo-Helastic Cotton, Germanie) ont été portés par les patients pour environ huit semaines après la guérison de la brûlure. Les changements de l'épaisseur de la cicatrice ont été misurés par PUSG avant le traitement et à intervalles de trois mois pendant la thérapie compressive. Nous avons conclu que la compression peut contrôler les cicatrices avancées en retard pour le traitement. Les modifications de l'épaisseur des cicatrices peuvent être objectivement mieux démontrées par FUSG que par l'évaluation clinique et la photographie.

BIBLIOGRAPHY

1. Baur P.S., Larson D.L., Stacey T.R. et al.: Ultrastructural analysis of pressure-treated human hypertrophic scars. J. Trauma, 16: 958, 1976.
2. Kischer CW., Shetlar M.R., Shetlar C.L.: Alteration of hypertrophic scars induced by mechanical pressure. Arch. Dermatol., I 11: 60,1975.
3. Larson D.L., AbstoD S., Evans E.B. et al.: Techniques for decreasing scar formation and contractures in the burned patient. J. Trauma, 11: 807,1971.
4. Leung P.C., Ng M.: Pressure treatment for hypertrophic scars.Burns, 6: 244, 1980.
5. Larson D.L., Abston S., Willis B. et al.: Contracture and scaf formation in the burn patient. Clin. Plast. Surg., 1: 653, 1974.
6. Alm S.T., Monafo W.W., Mustoe T.A.: Topical silicone gel for the prevention and treatment of hypertrophic scar. Arch. Surg., 126: 499, 1991.
7. Alexander 11, Miller D.: Determining skin thickness with pulsed ultrasound. J. Invest. Dermatol., 72: 17, 1979.
8. Cheng J.C.Y., Evans J.H., Leung K.S. et at.: Pressure therapy in the treatment of post-bum hypertrophic sear - a critical look into its usefulness and fallacies by pressure monitoring. Burns, 10: 154, 1984.
9. Bartell T.H., Monafo W.W., Mustoe T.A.: A new instrument for serial measurments of elasticity in hypertrophic scar. J. Bum Care Rehabil., 9: 657, 1988.

The preliminary scientific programme includes:

Different disasters and man-made accidents
Cooperation and coordination between all participating agencies, bodies and organizations at the disaster site
Education of the general public
Exhibitions including audio and visual means, computer self teaching program in rescue techniques, etc., to be presented at the venue

For further information contact:

Secretariat: 9th World Congress on Emergency and Disaster Medicine
P.O. Box 50006
Tel Aviv 61500, Israel
Phone: 972 35140014
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