ACNE SCARS and Collagen

 J AM ACAD DERMATOL
VOLUME 59, NUMBER 4
Rivera 661

Histologically, normal-appearing dermis demonstrates relaxed, randomly aligned collagen. Both hypertrophic scars and keloids demonstrate thicker, more abundant collagen that is stretched and aligned in the same plane as the epidermis. More specifically, hypertrophic scars have islands of dermal collagen fibers, small vasculature, and fibroblasts throughout. 15

Suggested pathophysiology includes transforming growth factor-beta-I, platelet-derived growth factor, matrix metalloproteinases, interleukin- I-alpha, fibroblasts themselves, altered microvascular regeneration, histamine, carboxypeptidase A, prostaglandin D2, and tryptase.16

Keloids, on the other hand, reveal regions of reticular dermal acellular nodelike structures and are more acellular as a whole compared with hypertrophic scars. Both keloids and hypertrophic scars have an incidence 5 to 15 times higher in African Americans and 3 to 5 times higher in Asians compared with Caucasians.17

It is estimated that they affect both the African American and Hispanic populations between 4.5% to 16%.18

As briefly noted above, both are treated either singly or in combination with multiple therapies such as excision, abrasion, laser treatment and medication, among others. As an outside reference, Alster and West19 authored an excellent, thorough review on hypertrophic and keloid scars along with atrophic scars.

The other cause of scars, loss or damage of tissue, is demonstrated by the 3 primary acne scars as described by Jacob et al20: icepick, rolling, and boxcar. The icepick scars are usually smaller in diameter (\\2 mm) and deep with tracts to the dermis or subcutaneous tissue possible. Although the orifice is smaller and steep-sided, there may be a wide base that could evolve into a depressed, boxcar scar. Commonly these are seen on the cheeks. Treatment is frequently done by punch excision with closure by small suture along relaxed skin tension lines. Nonabsorbable suture is preferred because of the predisposition of the skin to scar and the inflammatory response seen with absorbables. 21

Depressed or boxcar scars are described as shallow (\\0.5 mm) or deep ([0.5 mm) and are often 1.5 to 4 mm in diameter. They have sharply defined edges with steep, almost vertical walls. Shallow scar treatment can be with resurfacing or possibly punch elevation whereas deep scar treatment is most often done by punch excision, elevation, or other modality. Soft rolling scars can be circular or linear, are often greater than 4 mm in diameter, and have gently sloped edges that merge with normal-appearing skin. There may be dermal or subdermal tethering, so treatment is commonly by subcision, which will be discussed later. An additional, sometimes categorized class, atrophic scars, exhibit a slightly wrinkled texture and may be somewhat pigmented because of the underlying vasculature. Treatment is most often with abrasion, excision, or augmentation but occasionally with creams or peels that have generally poor results.

Objective evaluation of the scars is a necessity for discussion, treatment, and research. There are grading devices that focus on 3-dimensional grid-based mapping of lesions and molded skin replicas for comparison examination.22

However, these are not as applicable in practical, daily use by the average physician. There are grading scales for acne scars that are more practical for day-to-day implementation. In 1999, the ECLA (echelle d’evaluation clinique des lesions d’acne)23 was introduced, followed by the ECCA (echelle d’evaluation clinique des cicatrices d’acne)24 in 2006. Using this scale, the qualitative aspects of scars define the type of scar, which is then associated with a quantitative score (0-4) determined semiquantitatively and multiplied by a weighting factor (15-50) of clinical severity, leading to possible totals of 0 to 540. It was found to have good interinvestigator reliability although it did not focus on icepick, rolling, or boxcar specifically but rather variations of atrophic and hypertrophic.

Goodman and Baron25 described a quantitative grading system based on counting (1-10, 11-20, [20) of scar type (atrophic, macular, boxcar, hypertrophic, keloidal) and severity (mild, moderate, severe). Points are assigned to each respective category and totaled within the range of a minimum of 0 to a maximum of 84. This was found to be reasonably accurate and reproducible with good interinvestigator reliability. The same physicians also outlined a qualitative (rather than quantitative) grading system26 that is simpler for quick, daily use. It distinguished 4 grades for level of disease: (1) macular, (2) mild, (3) moderate, and (4) severe. Subdivisions of macular disease are erythematous, hyperpigmented, or hypopigmented and those of mild to severe disease are atrophic and hypertrophic. Further specification includes the number of cosmetic units involved: A for focal or one lesion and B for discrete or 2 to 3 lesions. As the reader can appreciate, these systems and variation therein can become quite confusing. In the literature, there is one attempt at creating a comprehensive classification system based on several other systems.27 However, the lack of a true consensus scale hinders standardization of diagnosis and treatment of acne scarring.

Next Page

Acne Scarring A review and current treatment modalities

BACKGROUND and ACNE SCARS

ACNE SCARS page 2

ACNE SCAR TREATMENT and MEDICAL MANAGEMENT

SURGICAL MANAGEMENT

PROCEDURAL MANAGEMENT

PROCEDURAL MANAGEMENT page 2

TISSUE AUGMENTATION

TISSUE AUGMENTATION page 2

TISSUE AUGMENTATION page 3

TISSUE AUGMENTATION page 4

Light, laser, and energy therapy

Light, laser, and energy therapy page 2

Light, laser, and energy therapy page 3

Light, laser, and energy therapy page 4

Conclusion and REFERENCES

Manufacturers of brand name drugs mentioned in this article