Inflammatory pseudotumor of the maxillary sinus: CT and MR findings in six cases

• Published in: American journal of roentgenology (1976) Vol. 163; no. 3; pp. 689 - 692
• Main Authors: Som, PM, Brandwein, MS, Maldjian, C, Reino, AJ, Lawson, W
• Format: Journal Article
• Language: English
• Published: Leesburg, VA Am Roentgen Ray Soc 01-09-1994; American Roentgen Ray Society
• Subjects: Adolescent; Adult; Aged; Biological and medical sciences; Granuloma, Plasma Cell - diagnosis; Granuloma, Plasma Cell - epidemiology; Humans; Magnetic Resonance Imaging; Male; Maxillary Sinus - diagnostic imaging; Maxillary Sinus - pathology; Medical sciences; Middle Aged; Otorhinolaryngology (head neck, general aspects and miscellaneous); Otorhinolaryngology. Stomatology; Paranasal Sinus Diseases - diagnosis; Paranasal Sinus Diseases - epidemiology; Retrospective Studies; Tomography, X-Ray Computed; Tumors; Human; Pseudotumor; Maxillary sinus; ENT disease; Medical imagery; Inflammation; Computerized axial tomography; Paranasal sinus; Nuclear magnetic resonance imaging
• ISSN: 0361-803X; 1546-3141
• DOI: 10.2214/ajr.163.3.8079869

Inflammatory pseudotumor is a chronic inflammatory lesion of unknown origin. The purpose of this study was to analyze the CT and MR findings in six cases of inflammatory pseudotumor of the maxillary sinus in order to determine if there were any imaging findings that distinguish this lesion from the more common type of pseudotumor that occurs in the orbit.
Six patients with pseudotumor of the maxillary sinus were identified retrospectively. The diagnosis was based on biopsy specimens. Their CT scans and MR images were studied by two radiologists to identify specifically the presence of soft-tissue disease and the presence and type of any bone involvement.
CT and MR images showed some degree of involvement of the bony wall in all cases. All patients had a soft-tissue mass with mild enhancement on CT scans and intermediate signal intensity on both T1- and T2-weighted MR images.
Our experience shows that inflammatory pseudotumor of the maxillary sinus causes bone changes on CT and MR images, findings that mimic a malignant tumor. Bone involvement appears to be more common in pseudotumor of the maxillary antrum than in its orbital counterpart.