Rare kissing antra of the maxillary sinuses: clinical implications

Purpose: To report a rare anatomical variant of the maxillary sinuses, with radiological and clinical emphasis.

Methods: A 40-year-old male with recurrent acute rhinosinusitis presented to our center for clinical management. A computed tomography scan revealed the presence of an incidental anatomical variant of bilateral maxillary sinuses for which we coin the term "kissing antra".

Results: Kissing antra appearances on computed tomography consisted of enlarged bilateral palatine recesses of the maxillary antra that met in the midline across a narrow bony septum below the floor of the nasal cavity. The right palatonasal recess angle was markedly acute at 61° instead of the normal 90°.

Conclusion: Kissing antra of the maxillary sinuses are important for anatomists, radiologists and surgeons to be aware of, both as rare anatomical variants, as well as for their multiple clinical diagnostic and therapeutic implications that we discuss in this report.