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 Table of Contents  
ORIGINAL ARTICLE
Year : 2021  |  Volume : 34  |  Issue : 1  |  Page : 34-39

Fractional CO2 laser versus fractional CO2 laser with subcision in management of atrophic postacne scar


1 Dermatology, Andrology and STDs Department, Faculty of Medicine, Menoufia University, Menoufia, Egypt
2 Dermatology, Andrology and STDs Department, Berket El-Sabae General Hospital, Menoufia, Egypt

Date of Submission30-Apr-2019
Date of Decision27-May-2019
Date of Acceptance01-Jun-2019
Date of Web Publication27-Mar-2021

Correspondence Address:
Reem W Mousa
Berket El-Sabae, Menoufia
Egypt
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Source of Support: None, Conflict of Interest: None


DOI: 10.4103/mmj.mmj_160_19

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  Abstract 


Objective
To evaluate efficacy and safety of fractional CO2 laser treatment versus fractional CO2 with subcision in the management of atrophic postacne scars.
Background
Atrophic postacne scarring has always been a challenge to treat. Fractional CO2 resurfacing in combination with subcision is effective and well tolerated.
Patients and methods
This prospective study includes 50 patients with atrophic acne scars from Outpatient Clinic of Dermatology, Andrology and STDs Department. An informed consent was obtained. Patients from both sex at least 18 years with any types and any grade of atrophic postacne scars, and not receiving any treatment in the past 6 months for their scars were included. All patients were subjected to history taking, general examination, and qualitative grading of acne. Patients were divided into two groups: group A included 25 patients who were subjected to fractional CO2 laser, and group B included 25 patients who were subjected to subcision and fractional laser on the second day of subcision.
Results
Excellent satisfaction was 100% with grade 1 scar, and good satisfaction was more common with grade 2 scar (60%) in group A. There were highly statistically significant differences found between grade of scar and patient satisfaction in group A (P = 0.001). Excellent satisfaction was 90.91% with grade 1 scar, and good satisfaction was more common with grade 1 scar (57.14%) in group B. There were statistically significant differences found between grade of scar and patient satisfaction in group B (P = 0.028).
Conclusion
The combination of fractional carbon dioxide laser and subcision is safe and effective modality for the treatment of atrophic acne scars. Moreover, there were improvements in patient satisfaction, without considerable complication.

Keywords: atrophic acne scar, fractional carbon dioxide laser, subcision


How to cite this article:
Haggag MM, Farag AG, Mousa RW. Fractional CO2 laser versus fractional CO2 laser with subcision in management of atrophic postacne scar. Menoufia Med J 2021;34:34-9

How to cite this URL:
Haggag MM, Farag AG, Mousa RW. Fractional CO2 laser versus fractional CO2 laser with subcision in management of atrophic postacne scar. Menoufia Med J [serial online] 2021 [cited 2021 May 12];34:34-9. Available from: http://www.mmj.eg.net/text.asp?2021/34/1/34/311998




  Introduction Top


Acne scarring is an unfortunate permanent complication arising from acne vulgaris and is associated with significant psychological distress. The incidence of acne scarring is not well studied, but it may occur to some degree in 95% of patients with acne vulgaris [1]. Atrophic acne scars can result from inflammatory skin disease causing sufficient damage to the epidermis and to the dermal collagen. Facial scars resulting from any etiologies are associated with psychological trauma and loss of self-esteem. The atrophic facial scars are divided into different morphological types depending on the shape and depth of the scars [2]. The main morphological types of atrophic postacne scars are ice pick pitted scars, superficial or deep boxcar scars, and rolling scars. Treatment of each morphological scar type varies, and although one scar type responds the best to some treatment modality, the same treatment option may not be necessarily effective in other type of scars [3]. Facial scarring has always been a challenge to treat. Different treatment modalities have been used to ameliorate atrophic scars with varying degrees of success. Management of these scars includes various types of resurfacing, which have the disadvantages of either being too mild and ineffective or being too aggressive and complicated [4]. Subcision is a technique used to correct depressed defects as it breaks the fibrotic strands that tether the scar to the underlying subcutaneous tissue, in which the mechanisms of scar improvement are releasing fibrotic strands underlying scars, organization of blood in the induced dermal pocket, and localized connective tissue formation [5]. Fractional lasers treat only a 'fraction' or a column of the affected skin leaving intervening areas of skin untreated. Fractional CO2 laser resurfacing has been used in the treatment of atrophic scars with varying degrees of success [6].

The aim of this study was to evaluate efficacy and safety of fractional CO2 laser treatment versus fractional CO2 with subcision in the management of atrophic postacne scars.


  Patients and methods Top


This study included 50 patients with atrophic acne scars from both sexes of at least 18 years with any types and grade of atrophic postacne scars. They were selected from Outpatient Clinic of Dermatology, Andrology and STDs Department in Menoufia University. An informed consent form was signed by all participants, before study initiation, and the study was approved by the Committee of Human Rights in Research of Menoufia University. Exclusion criteria were as follows: receiving any treatment in the past 6 months for their scars, active acne, systemic isotretinoin in the past 6 months, intake of acne-inducing drugs, herpes labials, history of keloid, history of facial surgery or procedure for scare, bleeding disorders, anticoagulant therapy, pregnancy, lactation, systemic diseases that can impair healing (e.g. renal and hepatic diseases), neurotic patients, and unrealistic expectation. No concomitant cosmetic procedures were allowed between the laser sessions, and no topical drugs were prescribed except sunscreens and topical antibiotic creams in the postprocedure period. The studied persons were subjected to detailed history taking, thorough general and dermatological examination, Fitzpatrick skin type, and type of acne scar [2]. Assessment of acne scar severity was done before and after treatment through the application of Goodman and Baron qualitative grading system [7],[8]. According to treatment modalities, patients were divided into two groups:

Group A included 25 patients who were subjected to fractional CO2 laser; two patients were dropped off from the study before any procedure. The treatment area was cleansed of sebum and debris (including dirt, makeup, and powder) using a mild cleanser and 70% alcohol. A thick layer of EMLA 5% cream was then applied to the treatment site for 1 h before under occlusion. Before starting the procedure, the cream was removed with dry gauze, and the treatment site was once more cleaned with an antiseptic solution. Both the patients and the operators wore safety goggles during the laser session. Each patient received four sessions of nonablative fractional CO2 laser at 4-week interval. ATL-250 CO2 medical laser system (sealed off CO2 laser), having wavelength of 10.6 mm, with variable pulse duration (0.2–2 ms), up to 0.2 mm spot size, scanner area of 15 × 15 mm, and max power = 25 W. Different settings were used according to each individual case regarding the type of scar, severity, and skin type. In an attempt to avoid common adverse effects that occur with fractional laser treatment, a lower fluence was used in the first session and depending on the results. Treatment parameters were programmed in the laser system and were performed first by Super pulse mode at max power 4 along the edge of the scar, and at the center, one more pass was made along the scar by scanner mode by max power starting from 8 W and increase by 1 W every section. Time on 5 ms and PPI four in first pass and five in the second pass on the scar. All scars were treated individually in a similar fashion. After irradiation, the treated area was sufficiently cooled with icepacks for 10 min. Topical antibiotic gentamicin 2% ointment was used. The ointment was applied for 7 days as conservative precaution to prevent bacterial infections and provide a suitable environment for wound healing. Patients were advised to avoid sun exposure, and a physical sunscreen was prescribed after the procedure

Group B included 25 patients who were subjected to subcision and then fractional laser on the second day of subcision; three patients were dropped off from our study. Each patient in the study was subjected to four sessions once a month or till improvement, whichever is first. The subcision was carried out using a needle of 1.5 inch and 18 G (Nokor Admix, Beckton, Dickinson and Company, Franklin Lakes, NJ, US). The patients were instructed to avoid sun and heat for 2 days after each session; in addition, they were advised sunscreen and emollient to reduce postinflammatory hyperpigmentation, pain, and erythema. Preoperatively, patients was instructed to avoid anticoagulant medications such as aspirin, NSAIDs, vitamin C and E supplements for at least 1 week, and systemic isotretinoin treatment for at least 6 months. Subcision was performed by Nokor needle [9].

The skin was cleansed with alcohol. Surgical pen marker was used to outline the scars to be treated with the patient in an upright position. Local anesthesia was achieved with intralesional 2% lidocaine with epinephrine (1: 100 000). The needle on 3-ml syringe was inserted at a shallow angle, with the blade facing upward, at the periphery of the scarred area. When the needle was intradermal or into superficial subcutaneous layer, it is turned so that the tip is in a horizontal orientation (parallel to the skin surface), and the skin was elevated to improve skin traction and facilitate needle motion. The free hand was used to stabilize the site while the needle moves in a lancing or gentle piston like motion (backward and forward). The direction of needle motion was changed when resistance starts to decline; the needle was passed sideways in fanning motion until no resistance was felt (endpoint). Approach the scar from multiple puncture sites was allowed to release heavy fibrous bands. Firm pressure was applied for at least 5 min to achieve hemostasis.

Each of the enrolled patients were assessed before each session and in the three follow-up visits for evaluation of response using the following:

  1. Clinical assessment: it was done before each session and 4 weeks after the last session. On objective lines, an improvement of scarring by two grades or more was labeled as 'excellent' response, a 'good' response meant improvement by a single grade, and the response was labeled as 'poor' where scar grading remained the same after completion of treatment
  2. Photography: the photos were taken by Oppo mobile camera with 20 megapixel resolutions before starting treatment, at each session, and three months after the last session, using identical lighting situation and patient positioning
  3. Patient satisfaction: each participant was asked to rate his/her overall satisfaction with the treatment on each side after each session and at the end of follow-up period using visual analogue scale. Score of patient's satisfaction was then determined as follows:


    1. 0 (unsatisfied: 0%)
    2. 1 (slightly satisfied: <25%)
    3. 2 (satisfied: 25–60%)
    4. 3 (very satisfied: >60%)


  4. Adverse effects: adverse effects were all reported including prolonged erythema (erythema >3 days), pain (graded as mild, moderate, and severe), swelling, infection, hyperpigmentation or hypopigmentation bumps, or subdermal nodules formation.


Statistical analysis

The collected data were statistically analyzed using a computer software, statistical package for the social sciences, version 23 (SPSS; SPSS Inc., Chicago, Illinois, USA). For qualitative data, comparison between two groups and more was done using χ2. For comparison between means of two groups, parametric analysis (t-test) and nonparametric analysis (Z-value of Mann–Whitney U-test) were used. For comparison between means of the same group before and after treatment, parametric analysis (paired t-test) and nonparametric analysis (Z-value of Wilcoxon signed ranks test) were used. Correlation between variables was evaluated using Pearson's correlation coefficient. Significance was adopted at P value less than 0.05 for interpretation of results of tests of significance.


  Results Top


Patients were divided into two groups in this study. The mean age in group A was 21.280 ± 2.319 years and group B was 21.44 ± 2.293 years. Comparison between the two patient groups shows that mean ages were nearly equal between both the groups, with no statistically significant difference (P = 0.05). Females were more prevalent in both groups, with 68 and 60% in groups A and B, respectively. No statistically significant difference was found by comparison between the two patient groups regarding sex. The mean duration of acne scar history in group A was 5.200 ± 21.633 and group B was 5.28 ± 1.621 years. Comparison between the two patient groups shows that mean acne duration was nearly equal between both the groups, with no statistically significant difference (P = 0.05). This table shows that the types of scar were ice pick in five (20%), rolling in 16 (64%), and box scar in 18 (72%) patients in group A. In group B, scar types were ice pick in four (16%), rolling in 18 (72%), and box scar in 18 (72%). No statistically significant difference was found by comparison between the two patient groups regarding type of scar.

Grade 3 acne scars were the most common (44%), and the least common was grade 2 (20%) in group A. In group B, grade 3 was the most common (48%), and the least common was grade 4 (24%). No statistical significant difference was found between both groups regarding grading in preintervention period. Grade 2 was the most common (30.4%), and the least common was grade 1 (21.7%) in group A. In group B, grade 1 was the most common (63.24%), and the least common was grade 3 (9.09%). There were statistically significant differences between both groups regarding grading in the postintervention period. There were statistically significant differences between both groups in preintervention and postintervention periods (P = 0.05), as shown in [Table 1].
Table 1: Comparison between two patients groups regarding grade of scar

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Excellent satisfaction was seen 17.39% in group A and 50% in group B. Poor satisfaction was the least common in group B (18.18%) versus group A (60.87%) [Table 2].
Table 2: Comparison between two patients groups regarding patient satisfaction

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There was a statistically significant difference between the two patient groups regarding patient satisfaction (P = 0.010). The adverse effects were slightly higher in group B than group A, with no statistically significant difference found between the two patient groups regarding adverse effects [Table 3].
Table 3: Comparison between two patients groups regarding adverse effects

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Regarding patient satisfaction with treatment, excellent satisfaction was seen with grade 1 scar (100%), good satisfaction was more common with grade 2 scar (60%), and poor satisfaction was more common with grade 4 scar (42.86%) in group A. There were highly statistically significant differences found between grade of scar and patient satisfaction (P = 0.001; [Table 4]).
Table 4: Relationship between grade of scar and patient satisfaction in group A

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Group B shows excellent satisfaction with grade 1 scar (90.91%), good satisfaction was more common with grade 1 scar (57.14%), and poor satisfaction was more common with grade 2 scar (75%). There were statistically significant differences found between grade of scar and patient satisfaction (P = 0.028; [Table 5]).
Table 5: Relationship between grade of scar and patient satisfaction in group B

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  Discussion Top


A total of 50 patients with atrophic acne scars were included. Group A included 25 patients who were subjected to fractional CO2 laser, and group B included 25 patients who were subjected to subcision and fractional laser on the second day of subcision. The common types of atrophic acne scars were box scar, rolling, and then ice pick in both groups. In 2006, Chivot et al. [10] found that in atrophic scars, the ice pick type represented 60–70% of total scars, the box scar 20–30%, and rolling scars 15–25%. Moreover, Nilforoushzadeh et al. [11], reported that 30 patients were affected by atrophic acne scar, ice pick type, and rolling, where 80% of the scars was of rolling type, 10% of the scars were of ice pick type, and the rest were of other types. Saeed and Alsaiari [12] in their study found the distribution of patients according to morphologic types was as follows: 40% of patients with acne scar had predominantly rolling scar, 37.5% had mixture of various morphologic scar subtypes, and 22.5% had predominantly pitting scar. In this study, qualitative scar grading system showed that grade 3 were most common (44%) in group A, and in group B, grade 3 was most common (48%), without statistically significant difference found between both groups regarding grading in the preintervention period. This was in agreement with Mohammad et al. [13] who stated that qualitative grading system of acne scars before and after treatment of the studied patients with different types of acne scars showed significant improvement in both groups. Moreover, Saeed and Alsaiari [12] found that all patients were with moderate-to-severe atrophic scars, where 31% had moderate acne scar and 9% had severe grade of acne scars, based on Goodman and Baron classification system. Our results showed that excellent satisfaction was seen in group A in 17.39% and in 50% in group B. There was a statistically significant difference found by comparison between two patients groups regarding patient satisfaction (P = 0.01). Our findings are closer to Badheka et al. [14], who found that excellent and good satisfaction results were seen in subcision group with fractional laser therapy at the end of treatment sessions in comparison with other methods. In line with several studies, Alster et al. [15], Glaich et al. [16], and Hasegawa et al. [17] reported that ∼77.5% (31 cases out of the total of 40) were satisfied with the treatment results regarding patient satisfaction assessment. Hedelund et al. [18] demonstrated statistically significant improvement in skin texture and atrophy in comparison with placebo after 3-monthly laser sessions. In 2010, studies of Bhardwaj and Khunger [19], Katz [20], and Chan et al. [21] reported that good to excellent response was achieved in ∼67% patients on the quartile grading scale.

In this study, group A shows excellent satisfaction with grade 1 scar (100%), and good satisfaction was more common with grade 2 scar (60%). In group B, excellent satisfaction was seen with grade 2 scar (90.91%), and good satisfaction was more common with grade 1 scar (57.14%). Subcision is a simple and certain surgical method for treating atrophic acne scar in which the scar levels are made free from the underneath connections, and it decreases the connective tissue formation under the scar without making any damage to the skin surface. Hence, subcision is a valuable method, but as it has a high risk of recurrence, the effectiveness of this method is considered low to medium by Harandi et al. [22]. Our findings were in line with several studies that confirmed value of combined therapy. Goodman [23] reported that of the entire scar types, rolling scars were seen to respond the best whereas ice pick pitted scars responded the least to treatment in the study population. This observation carries a lot of therapeutic importance as simple fractional laser resurfacing monotherapy is unlikely to take care of pitted scars. The results of Mohammad et al. [13] showed that subcision with fractional CO2 laser had 54.7% and fractional CO2 laser alone had 43% of recovery. In a study by Harandi et al. [22], conducted on the subcision method, it was reported that there was 60–90% improvement in depth and size of scars (significant improvement) in the patients, with mean of 71.73%. Approximately 28.2% of them had '80% improvement or more' (excellent improvement). In another similar study, the patients who had undergone subcision reported that it enhanced the outcomes versus the patients who had not [24]. Cho et al. [25] demonstrated the efficacy as well as safety of fractional CO2 laser resurfacing in acne scars. Half of the 20 patients enrolled in this study achieved clinical improvement of more than 50%, whereas another seven patients achieved 26–50% improvement. Furthermore, fractional lasers are effective in treating superficial textural irregularity and color variation but have limited ability to improve scars that are deep [26]. Several conflicts were shown in the therapeutic results obtained with fractional laser resurfacing. Lacking the uniform objective assessment of the satisfaction achieved therapeutically and the large portion of the clinical studies on resurfacing fractional laser procedure have been used with quartile grading systems or the satisfaction of the patient as the criteria to determine the results. In addition, there are just a few studies that reported the therapeutic benefits in various morphological types of acne scars [27],[28],[29]. In this study, adverse effects were slightly higher in group B than group A, with no statistical significant difference found between two patients groups regarding adverse effects (P = 0.68). Our findings regarding adverse effects agreed with Majid and Imran [4], as they reported that adverse effects seen were not significant, and none of the enrolled patients had any long-term or permanent adverse effects from the procedure. However, there is certainly some downtime associated with fractional CO2 laser resurfacing as patients do experience crusting for a few days after the procedure. This crusting makes it impossible for patients to resume their normal work for a few days after each laser session. In a study by Kang et al. [26], the use of combination of three methods such as subcision, dot peeling, and laser to treat acne scars, the results showed that severe acne scars decreased up to 53.3%, and 80% of the patients recovered, and there were no significant adverse effects in the treatment place. Fractional laser technology obviates many of these drawbacks as only a 'fraction' of the whole skin is treated and the integrity of epidermis is not compromised.


  Conclusion Top


The combination of fractional carbon dioxide laser and subcision is a safe and effective modality for the treatment of atrophic acne scars. Moreover there were improvements in patient satisfaction, without considerable complication. The varying morphology of acne scars, especially when multiple types of scars are found in the same patient, suggests the need for combination therapy to provide the most effective treatment. Fractional laser therapy is probably the only monotherapy that offers the highest degree of scar amelioration and patient satisfaction.

Financial support and sponsorship

Nil.

Conflicts of interest

There are no conflicts of interest.



 
  References Top

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    Tables

  [Table 1], [Table 2], [Table 3], [Table 4], [Table 5]



 

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