## 4 Discussion
The authors concluded that the study supported the effectiveness of bimatoprost used once daily in improving eyelash prominence in adults, as assessed through objective measures and patient-reported outcomes. Many other researchers confirmed the effectiveness of bimatoprost in treating hypotrichosis of the eyelashes. In a recent prospective study, [PERSON] et al. [28] investigated the usefulness of 0.03% bimatoprost for the management of eyelash loss in alopecia totalis and universalis. The patients applied bimatoprost solution to the eyelid margins once daily at bedtime for 12 weeks. The authors reported that an increase in eyelash length and thickness was observed only in those patients who had eyelashes present at the beginning of the study, and that there was no induction of new eyelash growth. Fewer studies have been conducted to explore the effectiveness of bimatoprost for enhancing eyebrows; however, bimatoprost solution is considered a potential off-label treatment for eyebrow hypotrichosis [29]. In our study, participants found bimatoprost preparation significantly more effective in improving eyebrow density and eyebrow hair elongation in comparison to sweet almond oil, although these findings were not confirmed by trichoscopy. [PERSON] and [PERSON] [30] described a case of a 60-year-old woman with idiopathic eyebrow hyporticbiosis who used a 0.03% bimatoprost solution once a day for 8 months. Alopecia in this woman was excluded. The researchers reported excellent and sustained growth of her hair, which became gradually visible over the observation period, as photographically documented. In a study by [PERSON] et al. [31], bimatoprost was significantly more effective in terms of hair growth and color change than a placebo. It is worth noting that the study conducted by [PERSON] et al. [31] was a multicenter, double-masked, randomized trial involving 357 participants with eyebrow hyportichosis, with results compared between three groups: bimatoprost 0.03% twice or once daily or vehicle twice daily. The primary endpoint was the 1-grade increase on the GlobalEyebrow Assessment (GEBA), which, after 7 months, was achieved by 83.9% of patients on bimatoprost used twice daily and 77.1% of patients on bimatoprost once daily in comparison to 43.0% of participants using the vehicle only (\(p<\) 0.001 for both comparisons). An average increase in eyebrow fullness, as measured with Digital Monitoring System Image Analysis (DMSIA), was 34.51 mm\({}^{2}\) in the bimatoprost twice-daily group and 30.96 mm\({}^{2}\) in the bimatoprost once-daily group versus 6.42 mm\({}^{2}\) in the vehicle group (\(p<\) 0.001 for both comparisons). Also, eyebrow darkness increased significantly when both bimatoprost groups (\(-\)4.53 IU and \(-\)3.76 IU) were compared with the vehicle group (0.11 IU) (\(p<\) 0.001 for both comparisons). Significantly more participants were satisfied with bimatoprost compared to the vehicle group starting from the second month, and this satisfaction level was maintained until the end of the study. [PERSON] [32] conducted a study in which 10 women randomly used bimatoprost on one eyebrow and a placebo on the other (split-face study) for 6 weeks. All participants reported significant subjective improvement in eyebrow hair growth, which was objectively confirmed by photographic documentation. In another split-face study, [PERSON] et al. [33] investigated the efficacy and safety of 0.01% and 0.03% bimatoprost in 30 patients suffering from eyebrow hypotrichosis. As assessed using the GEBA, both concentrations significantly improved eyebrow density and diameter (\(p<\) 0.05); 0.03% bimatoprost was numerically, but not significantly, better than 0.01% bimatoprost. Furthermore, patients preferred 0.03% bimatoprost due to its superior clinical effectiveness and perceived treatment satisfaction, with \(p\)-values of 0.04 and 0.003, respectively. Studies from the literature also compared bimatoprost to other substances used to promote hair growth, such as minor oxidil. [PERSON] et al.