## 4 Discussion
However, due to the limited examination area in our study, we cannot determine whether the vessels are primarily localized in the center, as noted in their work [18]. Figure 2A-D illustrates a diffuse arrangement of polymorphic vascular structures, comprising both linear vessel segments and irregular conglomerates, with connections that are difficult to clearly discern. In contrast, the 3D visualization in Figure 2E,F allowed for a detailed representation of vessel organization and polymorphism, showing both linear and glomerular vessels. A review of the literature on melanoma-associated vessels reveals that the term \"polymorphic vessels\" is frequently encountered, with the most common combination being dotted vessels and linear-irregular vessels [45]. Furthermore, [PERSON] et al. were able to demonstrate the polymorphism of blood vessels using D-OCT  
in comparison to healthy skin. In this study, a higher prevalence of linear and coiled vessels, some of which resemble glomerular vascular tufts, was observed when compared to healthy skin [40]. Additionally, the presence of distinctly varying vessel calibers is well-documented in the literature and is characteristic of melanomas and their vascular polymorphism [43]. However, little has been published on the distribution of vessels across multiple layers, likely due to the limited number of 3D visualizations of skin in existing studies. Future developments in LC-OCT technology could include the integration of AI-analysis capable of automatically detecting vessels in LC-OCT images. Our findings could be used as a foundation for the future training of AI models, since manual segmentation is time consuming. This AI feature would then not only assist in assessing the vasculature of skin tumors for treatment planning and monitoring but could also play a valuable role in the diagnosis and follow-up of inflammatory diseases. Moreover, with trained AI models, the 3D reconstruction of multiple skin tumors is possible in a very short time. Then our preliminary findings on 3D skin tumor vascularization could be confirmed in a larger study cohort. In the future, imaging technology is expected to achieve significant advancements beyond the current capability to visualize even individual blood cells within blood vessels. With the excellent axial and lateral resolution of less than 1.3 \(\upmu\)m, it will become possible not only to detect but also to differentiate these cells. This capability could be further enhanced with AI, which can analyze and classify complex patterns and features. Similar to flow cytometry, which is well-established in hematology, LC-OCT has the potential to analyze cells flowing through a vessel in vivo and in real-time [48]. Following appropriate manual annotation, AI could be capable of autonomously analyzing the physical and chemical properties of these cells. Another promising application of this technology is the future visualization of lymphatic vessels in the skin. With its high resolution and advanced imaging techniques, it may enable the production of detailed images that distinguish lymphatic vessels from blood vessels, providing new insights into the function and pathology of the lymphatic system. Moreover, it could provide an early, real-time view of potential lymphatic invasion in cases of melanoma in the future. A potential further limiting factor of this study is the influence of contact pressure during contact-based imaging with the LC-OCT system. Although pressure was deliberately minimized during measurements and visual feedback in the form of increased blood flow was used to ensure the most unbiased visualization of vascular structures, complete avoidance of pressure artifacts remains a challenge. The contact pressure can influence the morphology of the vessels, especially in sensitive tissue structures. In addition, minimizing pressure is highly dependent on the experience and care of the person performing the procedure.