## 4 Discussion  
This study aimed to investigate the effectiveness, safety, and user experience of bimatoprost topical preparation compared to sweet almond oil. We found that participants rated the bimatoprost topical preparation as more effective in improving eyebrow density and eyebrow hair elongation, but less effective in improving eyebrow hair hydration. No difference was found in perceived color change between the groups. Participants reported similar levels of comfort while using both preparations; however, they expressed significantly higher satisfaction with the bimatoprost topical preparation. Adverse events were minor and resolved spontaneously. No structural differences were found in the photographs or trichoscopy images between the groups at the end of each treatment. There is an ongoing interest in the aesthetic improvement of eyelashes and eyebrow hair. The first FDA-approved medicinal product indicated for the treatment of hypotrio-chosis of the eyelashes was Latisse. It was launched in 2008. The intended action was to increase the growth, including length, thickness, and darkness of eyelashes. Latisse is  
Figure 5: Photographs and trichoscopy images depicting areas of sparse eyebrow hair: top at baseline, middle after using the bimatoprost topical preparation, and bottom after using the sweet almond oil. Arrows indicate the area of the trichoscopy image. Figure 6: Trichoscopy images depicting eyebrows over 15 weeks of the study. available as a 0.03% bimatoprost ophthalmic solution. No contraindications for its use are mentioned in the product leaflet. Among adverse events that occur with a frequency of 3-4% are eye pruritus, conjunctival hyperemia, and skin hyperpigmentation [24]. Latisse was approved for use based on clinical studies. In the first proof-of-concept study, 0.03% bimatoprost solution was applied to the upper eyelid to enhance eyelash growth, color, and thickness. After 3 months, 81% of participants reported that their overall eyelash appearance was much improved, while 19% reported that their overall eyelash appearance was improved [25]. Another study conducted by Allergan aimed to expand the target population for Latisse to include pediatric patients and investigate safety in this population. A multicenter, double-masked, randomized, vehicle-controlled, parallel-group study included pediatric patients after chemotherapy, people suffering from alopecia area, and adolescents with a non-medical need. The study concluded that the adverse event profile aligns with those reported in previous studies of bimatoprost ophthalmic solution. There were no instances of iris hyperpigmentation or skin hyperpigmentation [25]. The focus of studies on bimatoprost has primarily been on the improvement of the condition of eyelashes. The reason for this was a higher percentage of eyelash changes reported as a side effect in studies investigating the efficacy of prostaglandin analogs in patients with open-angle glaucoma or ocular hypertension. In the meta-analysis by [PERSON] et al., eyelash change rates varied for different prostaglandin medications; however, all rates were high [26]. In 2013, [PERSON] et al. [27] conducted a randomized, double-masked, vehicle-controlled, parallel-group study to investigate the effectiveness of bimatoprost for hypotrichosis of the eyelashes. The study included 278 patients and lasted 5 months, with 16 weeks of active treatment. After completion of the active treatment phase, significantly greater improvements from baseline were observed on all Eyelash Satisfaction Questionnaire (ESQ) items, which measured improvement in length, fullness, and overall satisfaction with treatment. Additionally, a comparison between groups revealed that significantly better results were reported by the bimatoprost group than by the vehicle group in terms of length, fullness, and overall satisfaction (weeks 8-20; \(p\leq 0.0052\)); confidence, attractiveness, and professionalism (weeks 12-20; \(p<0.0001\)); and impact on daily routine (weeks 16 and 20; \(p\leq 0.01\)).