Post acne scarring is a common complication of acne. Cosmetic appearance of the post acne facial scarring can be improved by various methods. Among the procedural methods microneedling (1) is a novel and a promising option. It is a minimally invasive day care procedure for the management of atrophic acne scars. Topical tazarotene 0.1% gel is an effective medical method in the management of acne vulgaris and macular acne scars (2, 3). Based on its mechanism of action and role in collagen synthesis, topical tazarotene is a logical choice to investigate for the management of atrophic post acne scars. This is a pilot study comparing microneedling and topical tazarotene for the treatment of atrophic post acne scarring in regard to extent and rapidity of improvement, patient satisfaction and any adverse events if any.

Thirty six subjects with grade 2 to grade 4 atrophic post acne scars, classified on the basis of Goodman's Qualitative classification (4) criteria will be recruited. Goodman's qualitative and quantitative acne scarring grading system scoring will be performed for the assessment of severity of acne scarring at baseline. The face of each patient will be randomized for monthly microneedling on one side and topical tazarotene 0.1 % gel once a day local application on opposite side, using computer generated random number table. Follow ups will be done at every month until treatment completion (3 months) and 3 months after the last treatment session. Goodman's qualitative and quantitative acne scarring grading system scoring will be performed at 3rd and 6th month follow up visits. An improvement by two grades will be considered as excellent, one grade will be rated as good and no up gradation will be labelled as poor response. Patients will be also assessed by a blinded observer for clinical improvement and scored on a scale of 0 (no improvement) to 10 (maximum) at 3rd and 6th month follow up visits with the help of serial photographs taken under consistent background, position and lighting. All patients will be instructed to assess themselves using Patients' Global Assessment Score 0 (no response) to 10 (maximum) at 3rd and 6th month follow up visits.

The investigators hope the outcome of the present study may propose a newer medical modality for acne scarring, i.e topical tazarotene 0.1% gel, which can be used at home, obviating the need for physician dependant microneedling procedure.

Inclusion Criteria:

• Patients with grade 2 to grade 4 atrophic acne scars, classified on the basis of Goodman's Qualitative classification.6
• Should not have undergone any surgical and/or laser treatment for acne scars in the past 1 year.

Exclusion Criteria:

• Active acne
• History of keloidal tendency/hypertrophic or keloidal scarring on the face due to acne
• Facial scars due to reasons other than acne like varicella, trauma, burns etc
• Collagen vascular disease, bleeding disorders
• Any active bacterial , fungal or viral infection over face
• Pregnant and lactating females
• Known hypersensitivity to tazarotene
• Age less than 18 years
• Patients on anticoagulant therapy or aspirin

An independant senior dermatologist who is blinded regarding the modality used for atrophic acne scarring in each half of the face, will be assessing the outcome scores.