Hyperostosis of the Maxillary Sinus Wall in Aspergillosis: Is it a Characteristic Finding?

PURPOSE: To determine whether the wall thickening of the maxillary sinus is a characteristic finding in aspergillosis. MATERIALS AND METHODS: In 103 patients, including 26 with aspergillosis, 21 with inverted papilloma (IP), and 56 with unilateral chronic sinusitis, the thickness of the maxillary sinus wall was determined by CT scanning. All cases were proven pathologically, and patients with a history of previous surgery or bone destruction were excluded. Two neuroradiologists retrospectively reviewed the CT scans using bone window settings for sinus wall hyperostosis and the presence of intrasinus calcification. Thickening of the maxillary sinus wall was assessed visually in a semiquantitative manner, and graded as 'none'(absence of thickening), 'mild'(thickening of up to 1.5 times), or moderate to severe(over 1.5 times thicker than normal contralateral sinus wall at its thickest point). RESULTS: Moderate to severe wall thickening was found only in patients with aspergillosis (21/26, 80.8%). Mild wall thickening was seen in two patients with aspergillosis (2/26, 7.7%), in 12 of 21 with IP (57.1%), and in 5 of 56 with chronic maxillary sinusitis (8.9%). Most cases of chronic maxillary sinusits (51/56, 91.1%), 9/21 IP cases (42.9%), and 3/26 cases of aspergillosis (11.5%) showed no thickening of the maxillary sinus wall. Calcifications were found in 18 patients with aspergillosis (69.2%), in no patient with IP (0%), and in one with chronic maxillary sinusitis (1.8%). CONCLUSION: We suggest that 'moderate to severe' wall thickening of the maxillary sinus is the characteristic finding of aspergillosis. Although various sinonasal diseases can cause bone change, CT findings of hyperostosis of the maxillary sinus and intrasinus calcification are very helpful in differentiating fungal sinusitis from other types of chronic inflammatory lesions.

Nasal Tooth: Case Report

Ectopic tooth is not uncommon and usually occurs in the palate and maxillary sinus. We report a case of ectopic tooth located in the nasal cavity, a rare site. The mass depicted by CT was highly attenuated, and central lucency was observed.

Anatomical Relation between Anterior Ethmoidal Sinus and Lacrimal Sac Fossa on High Resolution CT

PURPOSE: To evaluate the anatomical relation between anterior ethmoidal sinus and the lacrimal sac fossa, and thus help prevent complications during dacryocystorhinostomy. MATERIALS AND METHODS: Fifty three people without previous history of trauma, surgery, or paranasal sinus disease were randomly selected, and the 106 lacrimal sac fossas of these subjects were evaluated by high resolution CT. A series of three 2-mm thick axial sections at least 2 mm from the inferior orbital wall were obtained. The bony landmarks of the lacrimal sac fossa were established and the location of the most anterior ethmoid sinus was classified as one of three types. In type 1, no sinuses were anterior to the posterior lacrimal crest. while in type 2, sinuses extended anterior to this crest but remained behind the suture at the anterior edge of the lacrimal bone. In type 3, sinuses extended into the frontal process of the maxilla, anterior to the lacrimal bone suture. In addition, the category of both orbits of the same patient was compared. RESULTS: Among the 106 orbits examined, only seven (6.6%) were classified as type 1, with no ethmoid air cells positioned under the lacrimal sac fossa. Seventy six (71.7%) qualified as type 2, while the remaining 23 (21.7%) were type 3, demonstrating anterior ethmoid air cells within the nasal process of the maxilla. The position of the air cells was symmetric in 41 of the 53 subjects (77.4%) and asymmetric in 12 (22.6%). CONCLUSION: In cases involving surgery of the lacrimal sac fossa, such as dacryocystorhinostomy, a knowledge of the consistent anatomic relationship between the anterior ethmoidal sinus and the lacrimal sac fossa is invaluable.

Anatomical Relation between Anterior Ethmoidal Sinus and Lacrimal Sac Fossa on High Resolution CT

PURPOSE: To evaluate the anatomical relation between anterior ethmoidal sinus and the lacrimal sac fossa, and thus help prevent complications during dacryocystorhinostomy. MATERIALS AND METHODS: Fifty three people without previous history of trauma, surgery, or paranasal sinus disease were randomly selected, and the 106 lacrimal sac fossas of these subjects were evaluated by high resolution CT. A series of three 2-mm thick axial sections at least 2 mm from the inferior orbital wall were obtained. The bony landmarks of the lacrimal sac fossa were established and the location of the most anterior ethmoid sinus was classified as one of three types. In type 1, no sinuses were anterior to the posterior lacrimal crest. while in type 2, sinuses extended anterior to this crest but remained behind the suture at the anterior edge of the lacrimal bone. In type 3, sinuses extended into the frontal process of the maxilla, anterior to the lacrimal bone suture. In addition, the category of both orbits of the same patient was compared. RESULTS: Among the 106 orbits examined, only seven (6.6%) were classified as type 1, with no ethmoid air cells positioned under the lacrimal sac fossa. Seventy six (71.7%) qualified as type 2, while the remaining 23 (21.7%) were type 3, demonstrating anterior ethmoid air cells within the nasal process of the maxilla. The position of the air cells was symmetric in 41 of the 53 subjects (77.4%) and asymmetric in 12 (22.6%). CONCLUSION: In cases involving surgery of the lacrimal sac fossa, such as dacryocystorhinostomy, a knowledge of the consistent anatomic relationship between the anterior ethmoidal sinus and the lacrimal sac fossa is invaluable.

CT Findings of the Angiomatous Polyp in the Nasal Cavity and Paranasal Sinus

PURPOSE: To assess the characteristic CT findings of the angiomatous polyp. MATERIALS AND METHODS: Fivecases of pathologically-proven angiomatous polyp were retrospectively evaluated. All underwent CT scanning, butin only four cases were postcontrast CT scans obtained. In analysing CT findings we focused on adjacent bonychange, and the extent and enhancement pattern of the mass. RESULTS: All but one case involved the maxillarysinus, showing thickening of the posterolateral wall and erosion or destruction of the medial wall. As forinvolvement of the anterior wall of this sinus, bony destruction was seen in one case, and thickening in three. Infour cases the tumor involved the maxillary sinus and nasal cavity, and two cases showed nasopharyngeal extension.No case involved the pterygopalatine fossa, however. On contrast enhanced CT scans(n=4), all cases showedenhancement as strong as blood vessels, and a multiple focal punctate or tubular pattern. CONCLUSION: Angiomatouspolyp tends to show bone thickening rather than bone destruction, not to involve the pterygopalatine fossa, and toreveal a strong punctate or tubular enhancement pattern. These findings may be helpful in the differentialdiagnosis of angiomatous polyp from other tumors such as maxillary cancer, angiofibroma and nasal polyp

Inverted Papilloma: CT and MR Imaging Findings in Correlation with Histologic Findings

PURPOSE:To evaluate CT and MR findings suggestive of inverted papilloma by correlation with pathologic findings. MATERIALS AND METHODS: The CT(n=16) and MR(n=8) findings of 22 pathologically proven cases of inverted papilloma in the sinonasal cavity were retrospectively reviewed with reference to location of tumor, density/signal intensity, contrast enhanced appearance, shape and cleft air shadow at the free margin of tumors, and mass effect. These findings and pathologic findings were then correlated. RESULTS: All 22 tumors were located in the unilateral nasal cavity and extended into the maxillary sinus(n=17), choana(n=10), ethmoid sinus(n=8), nasopharynx(n=7), nasal vestibule(n=5) or frontal sinus(n=1). All CT scans showed that the density of tumor masses was similar to adjacent muscle. Precontrast CT scans showed no visibles triations' within the tumor mass, but postcontrast scans revealed striations' of varying degree in six of nine cases. CT scans showed that the free margin of tumors was serrated(n=13) or lobulated(n=5), and in 13 cases cleft air shadow of varying shape was noted. All MR scans showed's triations' with intermediate/slightly high signal intensity on T1WI and intermediate/high on T2WI within tumor masses, which were more prominent on postcontrast scans. On MR, the free margin of tumors was seen to be serrated(n=5), lobulated(n=4), or smooth(n=1), but cleft air shadow was not detected. CONCLUSION: The triations' seen on postcontrast CT and MR images and the cleft air shadow with a serrated appearance seen on CT images at the free margin of tumors suggested the presence of inverted papilloma in the sinonasal cavity.

CT and MR evaluation of Choanal Polyps

PURPOSE: To evaluate the various types and CT and MR imaging findings of choanal polyps. MATERIALS AND METHODS: We classified 42 cases of surgically proven choanal polyps into three types according to site of origin,and retrospectively analyzed imaging findings; in the case of antrochoanal polyps, particulr attention was givento extension of the lesion into the nasal cavity. We also determined whether MR imaging can provide moreinformation than CT. RESULTS: The antrochoanal polyp was the most common type( 33/42 : 78.6% ). Three cases ofchoanal polyps(7.1%) originated in the sphenoid sinus (sphenochoanal polyps), and while six( 14.3% ) did notinvolve the sinus( pure choanal polyps ). Thirty-six of 42 choanal polyps(85.7%) extended into either the choanaor nasopharynx. Three cases of antrochoanal polyps protruded through the middle meatus, and two into theoropharynx. The maxillary sinus component of an antrochoanal polyps extended more frequently through the accessoryostium( 29/33 ) than through the natural ostium. For delineating the stalk of an antrochoanal polyp, MR imagingwas not superior to CT. CONCLUSION: The most common type of choanal polyp is the antrochoanal, followed by purechoanal and sphenochoanal. CT and MR imaging can help identify lesion continuity between a choanal polyp and theparanasal sinus.

Mucocele in Concha Bullosa: A Case Report

Mucocele of concha bullosa is rare and can be misdiagnosed as an intranasal tumor mass. We report a case ofmucopyocele of the concha bullosa.

Anatomical Relationship between the Optic Nerve and Posterior Paranasal Sinuses on Ostiomeatal Unit CT

PURPOSE: To determine the anatomic variations that can lead to optic nerve damage during the sugical treatment of posterior paranasal sinus lesions MATERIALS AND METHODS: two hundred optic nerves of 100 persons were examined using ostiomeatal unit CT (OMU CT). The anatomical features of this nerve and posterior paranasal sinuses were classified into four types : the optic nerve adjacent to the sphenoid sinus without indentation of the sinus wall (type 1); the optic nerve adjacent to the sphenoid sinus, causing indentation of the sinus wall (type 2); the optic nerve passing through the sphenoid sinus (type 3); and the optic nerve adjacent to the sphenoid sinus and posterior ethmoid sinus (type 4). Bony dehiscence around the optic nerve and pneumatization of the anterior clinoid process were also evaluated. RESULTS: The anatomical classification of the optic nerve and posterior paranasal sinuses was as follows : type 1, 1326 (66%); type 2, 60 (30%); type 3, 6 (3%), and type 4, 2 (1%). Bony dehiscence around the optic nerve had developed in 58 cases (29%) and pneumatization of the anterior clinoid process in 13 (6.5%). These conditions were most common in type 3 optic nerve, and second most common in type 2. CONCLUSION: The 2 and 3 optic nerve, bony dehiscence around the optic nerve and pneumatization of the anterior clinoid process are the anatomic variations that can lead to optic nerve damage during the surgical treatment of posterior paranasal sinus lesions. To prevent optic nerve damage, these factors should be carefully evaluated by OMU CT.

CT and MR Findings of the Inverted Papilloma

PURPOSE: The purpose of this study is to describe the CT and MR findings of inverted papilloma and to determine the specific differential finding between inverted papilloma with and without coexisting malignancy. MATERIALS AND METHODS: Twenty-two histopathologically proven inverted papillomas were included in this study; in six patients there was coexisting malignancy. Twenty-two CT images and eight MR images were retrospectively reviewed. RESULTS: On CT images, the inverted papillomas were seen as unilateral sinonasal masses with bone remodeling (n=15) rather than bone destruction (n=1) and showed iso- or slightly high attenvation. Three of the six malignant cases showed aggressive bone destruction and widespread extension into the orbit, intracranial and buccal spaces, and pterygopalatine fossa. On MR images, the inverted papillomas (n=3) were iso- (n=2) or slightly high (n=1) in signal intensity in relation to muscle on T1 weighted images, and high (n=3) on T2 weigihted images. Gadolinium enhanced images showed heterogenous moderate enhancement. In the cases of coexisting malignancy (n=5), the masses were iso- (n=5) on T1 weighted images, high (n=5) on T2 weighted images and also showed heterogenous moderate enhancement. CONCLUSION: Inverted papilloma should be considered in the differential diagnosis of a bulky unilateral nasal mass extending into the adjacent paranasal sinuses, especially in an elderly patient with chronic nasal obstruction. Although there were no specific differential findings in signal intensiy and enhancement pattern on CT and MR images between benign and malignant inverted papilloma, aggressive bone destruction and widespread extension beyond the sinonasal cavity are findings which are highly suggestive of coexisting malignancy.

CT Findings of Inverted Papilloma and Aspergiollosis in Sinonasal Cavities: CT differentiation

PURPOSE: To describe the characteristic CT findings of inverted papilloma (IP) and aspergillosis involving sinonasal cavities and to differentiate between them on CT. MATERIALS AND METHODS: We retrospectively reviewed CT images in 22 cases of pathologically confirmed IP and 16 of aspergillosis; these were classified as one of four types, according to location. We also analyzed infundibular widening, displacement of the maxillary medial wall, the presence of air in the maxillary ostium, elevation of ethmoidom axillary plate (EMP), calcification within a lesion, reactive hyperostosis and CT density. RESULTS: Four cases were type I, which was seen only in aspergillosis (4/16, 25%); five were type IV, and all were IP (5/22, 22.7%), with a characteristic growing vector. Type II was seen in nine cases of IP and 11 of aspergillosis, and type III in eight cases of IP and one of aspergillosis. In types II and III (17 of 22 cases of IP; 12 of 16 of aspergillosis), five of 22 cases of IP (22.7%) and nine of 16 of aspergillosis (56.3%) showed infundibular widening, which was more severe in aspergillosis. Maxillary medial wall displacement was seen in five of 22 cases (22.7%) of IP, four of which showed lateral displacement and in five of 16 cases (31.3%) of aspergillosis, all of which showed medial displacement. Air in the maxillary ostium was seen in seven of 22 cases of IP (31.8%). Elevation of EMP was seen in two cases of IP (9.1%) and three of aspergillosis (18.8%), which showed oblique elevation. Calcification was detected in nine cases of aspergillosis (56.3%) but in only one of IP. Reactive hyperostosis was seen in 13 cases of aspergillosis (81.3%) and two of IP (9.1%). CONCLUSION: Although it is hard to differentiate between IP and aspergillosis involving sinonasal cavities, the findings of calcification, infundibular widening, air in the maxillary ostium,displacement of the maxillary medial wall, an elevated EMP pattern and reactive hyperostosis combined with duration of symptom may be helpful.

The Role of Three-Dimensional Imaging in Evaluation of the Sinonasal Mass

PURPOSE: To investigate the role of 3D imaging in the sinonasal mass. MATERIALS AND METHODS: Twenty patients with sinonasal mass(squamous cell carcinoma[n=6], spindle cell carcinoma[n=1}, angiomatous polyp[n=1}, giant cell reparative granuloma[n=1}, non-Hodgkin's lymphoma[n=1}, melanoma[n=1}, angiofibroma[n=1}, pyocele[n=1}, inverted papilloma[n=1}) were studied with spiral CT. Reconstruction of surface rendered 3D images and segmentations were performed and compared with the 2D image. RESULTS: The 3D images enabled easy understanding of the characteristics of the mass in 12 casese. The 3D images displayed pathway of tumor extension in 5 cases and werehelpful in assessing the primary site of the mass in 3 cases. In two cases with encasement of ICA by the mass, assesment of relationship between the mass and vessels were possible through the segmentation. CONCLUSION: The 3D image, as an adjunct to the 2D image, can help to evaluate the virtual appearance of bony change, the degree of extension of mass, the spreading route, the evaluation of origin site. It also provides valuable 3-dimensional conception of the mass, especially for the surgeon.

Evaluation of the Dynamic Patency of the Frontonasal Duct: Value of PNS CT Scan after Administration of anlsoosmolar Contrast Agent for Low lrritation into the Nasal Cavity

PURPOSE: To evaluate the dynamic patency of the frontonasal duct(FND) on PNS CT scan after administration ofan iso-osmolar contrast agent (lsovist) into the nasal cavity. MATERIALS AND METHODS: Coronal PNS CT scans from ten normal and 30 patients with symptoms of chronic sinusitis were obtained after administration of lsovist intothe nasal cavity, followed by Valsalva maneuver for the even distribution of the agent into the FND and sinuses. Atotal of 80 FNDs were evaluated for dynamic patency by examining the presence of the contrast agent in ducts. RESULTS: The contrast agent was visualized in 34/37 FNDs(91.9%) without ipsilateral frontal sinus it is and was visualized in 18/43 FNDs(41.9%) in cases of ipsilateral frontal sinusitis. In addition, the contrast agent within the ipsilateral frontal sinus was visualized in 8/18 FNDs(44.4%). The major causes of ductal obstruction were mucoperiosteal thickening and polypoid lesions secondary to inflammation. CONCLUSION: PNS CT scan together with the administration of lsovist, which caused minimal irritation, was useful for the evaluation of the relationship between the dynamic patency of the FND and frontal sinusitis, In addition, this study can provide the rhinologist with accurate anatomical and pathological information concerning the FND before a choice is made between endoscopic sinus surgery or medical treatment.