Incidental Para-Nasal Polyps on Brain MRI Images in a Cameroonian Population

Abstract

Rationale: Paranasal polyp is a soft tissue pear-shaped mass seen in the sinuses around the nostril. Allergy and inflammations are the major implicating factors. Small polyps could be of no concern to patients but large size could be a disturbance with perennial nasal obstruction and rhinorrhea. MRI with its superlative soft tissue contrast and multi-planarity facilitates the detection of paranasal polyps in brain MRI even when the referral is un-related to otorrhinolarygological features.Objective: To evaluate the prevalence and regional localisation of incidental polyps seen in brain MRI. Design and equipments: Prospective pioneer study using 0.3Tesla Hitachi AIRIS 11 MRI equipment. Setting: Polyclinic Bonanjo, Douala, Cameroon, a Specialist Hospital. Patients: 103 Patients referred for brain MRI from June 2009- Jan 2010 with only neurological symptomatology. Main outcome measured: Paranasal sinus was evaluated for polyps using T1W, T2W, FLAIR in different acquisitions. Results: 103 Patients were studied, 20 Patients had paranasal polyps with 14 (70%) males and 6 (30%) females forming a ratio of 2.33:1. Peak age range was 20-29years with 7 polyps (30%) followed by 50-59years with 25%. Polyps were rare in extremes of age. These 20 patients had 23 polyps due to 2 cases of bilateral maxillary polyps and single case of multiple polyps. The highest number of paranasal polyps 17 (73.91%) were in the maxillary sinus, followed by sphenoidal and frontal sinuses. Majority of polyps were pedunculated and < 2cm. Conclusion: Paranasal polyps are easily detected by MRI. The highest location is in the maxillary sinus with male preponderance.