Evaluation of Fractional CO<sub>2</sub> Versus Long Pulsed Nd:YAG Lasers in Treatment of Hypertrophic Scars and Keloids: A Randomized Clinical Trial
Bibliographic record
Abstract
Background Keloids and hypertrophic scars are challenging to both patients and physicians. They can be aesthetically disfiguring, functionally debilitating, and emotionally distressing. Lasers have introduced new mechanisms to improve scars both on aesthetic and symptomatic levels. Aim of Work Comparing the efficacy of fractional CO 2 laser, long‐pulsed Nd:YAG laser and their combination in the treatment of hypertrophic scars and keloids on clinical, histopathological, and biochemical basis. Patients and Methods Thirty patients with hypertrophic scars and keloids were enrolled in the study. Three scars in each patient were randomly assigned to treatment modalities (i) Fractional CO 2 , (ii) Nd:YAG laser, (iii) Combined CO 2 and Nd:YAG lasers. For each treatment area four sessions, 4–6 weeks apart were performed. Clinical evaluation was done before and 1 month following last session using the Vancouver Scar Scale (VSS) and the Patient and Observer Scar Assessment Scale (POSAS). Routine hematoxylin and eosin, Masson's trichrome, and Orcein stains were used to evaluate the appearance and pattern of dermal collagen and elastic fibers. Image analysis was used to quantitatively assess the density of collagen and elastic fibers. Biochemical evaluation of tissue level of transforming growth factor‐β I (TGF‐β I) and TGF‐β III was performed using enzyme‐linked immunosorbent assay studies. Results Both VSS and POSAS showed significant improvement following treatment with the three used modalities. Collagen fibers showed significant improvement as regards appearance and pattern while it was insignificant as regards density. Elastic fibers density improvement was only significant in fractional CO 2 (treatment area A). Hypertrophic scars showed more significant improvement with fractional CO 2 laser, while in keloids there was no significant difference between the three modalities regarding improvement. Level of TGF‐β I showed significant reduction after treatment in all treatment modalities, while TGF‐β III levels showed insignificant elevation in all treatment modalities. Side effects were significantly higher in treatment area C (combined treatment). Conclusion Long pulsed Nd:YAG laser is effective and safe treatment of hypertrophic scars and keloids. Fractional CO 2 laser yields better improvement in hypertrophic scars, while in keloids both fractional CO 2 and Nd:YAG lasers achieve comparable improvement. Combination in the same session did not add significant additional benefit and the side effects profile was higher. Limitations small sample size and short follow‐up period. Lasers Surg. Med. © 2020 Wiley Periodicals, Inc.
Fetched live from OpenAlex and de-inverted. Abstracts are not stored in this database: the inverted indexes are 8.6 GB of the frame’s 9.3 GB of text, and the host has 13 GB free.
How this classification was reachedexpand
Full frame distilled prediction
Teacher imitationNot calibrated prevalence, not ground truth. Human validation pending. Learned from the 10,348 direct Codex labels and 10,348 direct Gemma labels. Candidate is the union of thresholded teacher heads; consensus is their intersection. These outputs are machine_predicted_unvalidated and are not human labels or direct frontier model labels.
Codex and Gemma teacher scores by category
| Category | Codex | Gemma |
|---|---|---|
| Metaresearch | 0.004 | 0.004 |
| Meta-epidemiology (narrow) | 0.000 | 0.000 |
| Meta-epidemiology (broad) | 0.002 | 0.000 |
| Bibliometrics | 0.000 | 0.000 |
| Science and technology studies | 0.000 | 0.001 |
| Scholarly communication | 0.000 | 0.000 |
| Open science | 0.000 | 0.000 |
| Research integrity | 0.000 | 0.000 |
| Insufficient payload (model declined to judge) | 0.000 | 0.000 |
Machine scores (provisional)
The two teacher heads of the student model, read on this work. A score orders the frame for review; it never asserts a category, and the validation status ships verbatim with every row.
Baseline scores from an immature model (maturity gate not passed, 7 training rounds). Scores rank; they never assert a category.
score_only:v0-immature-baseline · verbatim from the scoring run: score_only means the number may rank works, and no category label ships from itClassification
machine, unvalidatedMachine predicted; a candidate call from one teacher head, not a consensus.
How this classification was reached, model by model and score by score, is at the end of the page under "How this classification was reached".