What is meant by osteomeatal complexes are patent bilaterally?

When the osteomeatal complexes are patent bilaterally, it indicates that both openings that connect the frontal and maxillary sinuses to the nasal cavity, also known as osteomeatal openings or ostia, are clear and unobstructed. This is considered a normal anatomical variation, and it allows for proper drainage and ventilation of the sinuses, ensuring their optimal functioning.