Scars

Close inspection of acne skin can reveal some scarring in up to 90% of individuals . But significant scarring occurs in 22%. Scars may show increased collagen or be associated with loss of collagen
Types scars
Macular-(Flat): Hyperpigmented tiny flat scars. They are more common in darker skinned patients and in those who pick their lesions (acne excoriee).
Depressed(Ice pick): These are sharp, deep, depressed scars, wider at the surface and narrow at the base. -Rolling: These are distensible, depressed scars with gentle sloping edges. -Boxcar: These are shallow or deep, punched out scars, wide at the surface and the base.
Elevated(Hypertrophic): These are elevated, fibrotic scars, more common in males and frequently seen in the mandibular area of the face and back. -Keloidal: These are keloids developing in acne lesions. They are seen more often in males, on the back and chest. -Papular: These scars are raised, papular and fibrotic, most commonly seen on the chin and nose. -Bridging scars and sinus tracts: These are multiple linear scars, joined together by epithelial tracts containing foul-smelling products of sebum.

Pigmented marks

In some of the individuals, acne heals with black pigmentation known as acne marks. They usually takes time to disappear. Duration of the marks to disappear depends upon the depth of the pigmentation. If the pigmentation is associated with acne, azelaic acid and adapalene are commonly used. Where as for pigmentation alone, skin lightning creams containing hydroquinone and arbutin are used .Chemical peeling like glycolic acid peeling also help to reduce the pigmentation. Glycolic acid 20-35%. is used It is well tolerated and does not produce systemic toxicity. It is an effective peeling agent even when used in lower concentrations and has a long shelf life.

Physical modalities

Facial saunas, heat and massage probably worsen the condition by precipitating the development of inflamed lesions. Removal of comedones can, however, be aided by hot compresses. Comedone removal can be surprisingly uncomfortable and a variety of specially shaped tools, particularly for blackhead removal, are available. After cleansing with spirit, the comedone extractor is centred over the comedone and firm downward pressure is applied along the direction of the hair follicle to express the contents.For closed comedones, the top of the lesion is first pierced with a 21 G needle to make extrusion less traumatic. Undue force, which could increase inflammation and lead to potential scarring, should never be applied.
Light cautery after the application of a local anaesthetic (EMLA) has been shown to help patients with multiple macro-whiteheads and blackheads (up to 1.5mm diameter).The EMLA is applied for 60-90min beneath an occlusive dressing. The cautery is used at a very low setting so as to produce little or no pain. The aim is to produce very low-grade thermal damage so as to stimulate the body's own defence mechanisms to eradicate the comedo. The actual cautery procedure takes 5-10min and is associated with very little scarring or postinflammatory pigmentation. Such therapy is more effective than topical tretinoin.
Superficial freezing with liquid nitrogen will hasten the resolution of chronic fluctuant nodular lesions and is comparatively painless. Two freeze-thaw cycles of 15sec each are recommended. It is uncertain how this treatment works, but it probably invokes an inflammatory reaction, so breaking down the indolent tissue surrounding the lesion. Cryotherapy is superior to intralesional steroid injections in the treatment of older (7 or more days) nodular lesions, whereas intralesional steroid is preferred in lesions less than 7 days old. Triamcinolone, 2.5mg/ml, may be administered from a syringe with a 30-gauge needle. Placement too superficially or too deeply may cause atrophy; 0.025-0.1ml should be injected into the middle of the lesion, causing slight distension. Aspiration before the steroid injection is desirable, but not always possible because of the nature of the fluctuant nodular lesions, which are not true cysts. Chemical peeling also helpful as an adjuvant treatment for actve acne. Salicylic acid 20-30% is the peeling agent of choice in acne as it has keratolytic and anti-inflammatory properties. As it is lipophilic in nature, it can easily penetrate the pilosebaceous unit.