The orbit constitutes a narrow anatomical space housing numerous important anatomical structures. Diseases affecting the orbit encompass a spectrum of conditions including inflammatory, neoplastic, vascular, traumatic, congenital, periorbital, and systemic manifestations [15]. Surgical interventions have been effective in addressing various orbital diseases. The history of orbital surgery dates back to Krönlein’s pioneering work in 1889, where he first reported successful removal of endoorbital cysts via a transorbital approach [16]. Subsequently in 1922, Dandy introduced the transcranial approach for treating orbital lesions, marking significant milestones in the evolution of surgical techniques for orbital pathology [17]. Since then, both transorbital and transcranial approaches have undergone progressive development in the treatment of orbital lesions.

Li et al. segmented the orbit into four quadrants—inner-superior, outer-superior, inner-inferior, and outer-inferior—using horizontal and vertical lines passing through the optic nerve as demarcations [11]. The infraorbital region encompasses the inner and outer inferior quadrants. The initial surgical approaches studied for lesions in the infraorbital region were transcutaneous methods [18]. Bourguet first described the transconjunctival approach in 1924, making significant contributions to orbital surgery [19]. Tenzel and Miller later advocated for its use in accessing small orbital floor fractures [20]. Kennerdell et al. proposed the transmaxillary sinus approach for successful resection of apical orbital tumors involving the optic nerve [21]. Saskia and Schultheiß et al. highlighted the transmaxillary approach as providing an excellent perspective of the infraorbital region with fewer postoperative complications compared to transcutaneous and transconjunctival approaches [22, 23]. However, it should be noted that all these approaches involve external incisions of varying sizes, which may impact patients’ maxillofacial aesthetics differently.

Over the years, advancements in endoscopic technology and surgical equipment have led to a gradual increase in the number of endoscopic operations for managing orbital lesions [24]. However, the primary procedure remains the decompression of the optic nerve canal [25]. Endoscopic treatment of intraorbital lesions primarily targets inferomedial intraconal space lesions [26]. Nevertheless, there is a notable absence of literature on endoscopic management specifically focusing on lesions confined to the infraorbital region, particularly the lateral infraorbital region. Therefore, this study aimed to explore the feasibility and safety of endoscopic management for such lesions.

In this anatomical study, we demonstrated the successful application of PLRA to access the infraorbital region. Using a 70° scope, we accurately delineated the maximum boundary of the medial infraorbital quadrangle within the infraorbital region. Additionally, we conducted a comparative analysis of the PLRA with other surgical approaches commonly used for managing infraorbital lesions.

For lesions in the infraorbital region, the PLRA offers several advantages over traditional approaches. Firstly, it avoids the need for external incisions, providing a minimally invasive alternative, Secondly, it allows access to the medial infraorbital region without the risk of traction on the optic nerve, a concern with lateral transorbital approaches. Similarly, compared to the transethmoidal approach, the PLRA reduces traction to the nasal septum while facilitating access to the lateral infraorbital region without risking optic nerve injury.

Furthermore, the PLRA minimizes the extent of external incisions compared to approaches such as the transconjuntival and the transmaxillary approaches. Therefore, the PLRA represents a novel approach for treating lesions affecting the infraorbital region, offering advantages over traditional open approaches.

The PLRA utilizes the natural corridor of the maxillary sinus through the medial infraorbital quadrangle to access the infraorbital region. In our study, we successfully accessed the infraorbital region via the PLRA without causing damage to nerves, blood vessels, or muscles. Importantly, this approach allows for adequate exposure of the lateral compartment without the need to inferiorly transpose the infraorbital nerve. For deeper lesions requiring treatment, selective removal of a portion of the medial wall of the maxillary sinus can be performed to create additional space for manipulation. However, it is essential to note that accessing deeper structures such as the superior rectus muscle through the medial infraorbital quadrangle may necessitate removal of orbital fat. This procedure increases the risk of potential damage to neurovascular structures. As a precautionary measure, we do not recommend using the PLRA for treating lesions above the level of the optic nerve.

Additionally, the PLRA creates two types of bone defects when accessing the infraorbital region. One defect occurs during access to the maxillary sinus through the PLRA, while the other is formed through the orbital floor. The bone defect from accessing the maxillary sinus can be repaired by suturing an inferior turbinate mucosal flap. However, defects in the orbital floor resulting from fat removal may lead to complications such as diplopia and enophthalmos [27]. Autologous fat transplantation is a viable option clinical surgery to mitigate postoperative complications such as enophthalmus [28]. Techniques described in the literature on endoscopic repair of infraorbital wall fractures can also guide effective wall repair, with material selection tailored to the size of the bone defect [23, 29,30,31].

However, several considerations must be addressed before further discussing the PLRA’s approach to the infraorbital region. This study did not involve specific surgical cases, limiting direct application to clinical scenarios. Moreover, the PLRA crosses the optic nerve, posing limitations in treating lesions located above the anatomical landmark. Additionally, during actual operations, there is a risk of damaging smaller branches of the ophthalmic artery. The removal of fat tissue can also complicate identification and protection of the ciliary nerve, potentially resulting inn nerve damage. Therefore, it is crucial for surgeons to thoroughly understand these anatomical structures when employing the PLRA from an endoscopic perspective. Overall, with advancements in endoscopic techniques and materials for orbital floor repair, the safe application of this research in patient surgeries is increasingly feasible and reasonable.