Radiological evaluation of the recesses on the posterior wall of thenasopharynx using cone-beam computed tomography

ABSTRACT Radiological Evaluation of the Recesses on the Posterior Wall of the Nasopharynx Using Cone-Beam Computed Tomography The nasopharyngeal region holds significant importance for both radiological evaluation and clinical intervention due to its complex anatomical structures and histological diversity. In particular, clear visualization of structures such as the Rosenmüller fossa and the pharyngeal opening of the eustachian tube plays a critical role in the early diagnosis of malignancies such as nasopharyngeal carcinoma. In this study, morphometric analyses of the Rosenmüller fossa, pharyngeal bursa, and eustachian tube opening were performed using cone-beam computed tomography images. Cone-beam computed tomography images from a total of 150 patients were retrospectively examined. Quantitative data were obtained for the width, depth, and length determined in sagittal sections of the Rosenmüller fossa and pharyngeal opening of the Eustachian tube, as well as their distances from the posterior end of the nasal septum and the midsagittal axis and the angles they formed with the midsagittal axis. Also, the prevalence of the pharyngeal bursa and, where present, its width, depth, and length in sagittal sections were also recorded. These data were analysed according to age and gender. Our findings indicate that the parameters of the Rosenmüller fossa and Eustachian tube opening vary according to age and gender, and that statistically significant differences were observed in some measurements according to Rosenmüller fossa types. Furthermore, the dimensional relationship between Rosenmüller fossa width and depth and Eustachian tube opening showed a positive correlation (p<0.05). The data obtained indicate that there are significant relationships between the types of the Rosenmüller fossa and Eustachian tube opening measurements. Knowledge of the anatomical structures located in the nasopharyngeal region may assist in the detection of early-stage malignancies such as nasopharyngeal carcinoma and in the interpretation of deviations from normal. Our study demonstrates that nasopharyngeal morphometric analyses performed using cone-beam computed tomography provide clinically and radiologically meaningful data and may serve as a reference for future studies in this field. Keywords: Cone-beam computed tomography, eustachian tube, nasopharynx, pharyngeal bursa, rosenmüller fossa.