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Objective To study the HRCT features of pneumatized inferior turbinate and to evaluate their diagnostic value.Methods Twelve cases of pneumatized inferior turbinates demonstrated by HRCT were retrospectively analyzed.Results Coronal HRCT could demonstrate pneumatization of the inferior turbinate clearly and directly.Unilateral pneumatization was found in 11 cases and bilateral in one case. According to the location of pneumatization,pneumatized inferior turbinates were classified into three types : bulbous,lamellar,and extensive types.Five of 12 cases were bulbous,5 were lamellar and 2 were extensive type.On coronal HRCT scans,bulbous type showed nodular shape in one case,oval and ellipse shape in 2 cases each,respectively.Lamellar pneumatization appeared as curved stripe-like shape in 4 cases communicating with the maxillary sinus and ellipse shape in one case.Extensive type was found in 2 cases, curled lamella-like shape was found in 1 case communicating with the maxillary sinus and ellipse shape in another case.In 5 cases with maxillary sinus communication,axial HRCT revealed a defect on the medial wall of the maxillary sinus.In such a condition,the maxillary process of palatine bone and maxillary bone attached to the lower turbinate separately.Conclusion HRCT was an optimal imaging modality for the diagnosis of pneumatization of the inferior turbinate and may help the clinicians to differentiate from other causes of the inferior turbinate hypertrophy.
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Objective To investigate the CT and MRI findings of cavernous hemangioma in paranasal sinus so as to promote the diagnostic accuracy.Methods All 30 cases of cavernous hemangioma in paranasal sinus were verified with pathological examinations.The CT and MRI findings were analyzed retrospectively.Results The lesions occurred in the maxillary sinus in 25 cases,in the anterior ethmoid sinus in 3 cases and in the sphenoid sinus in 2 cases.The lesions extended and compressed adjacent structures.MRI showed the extent and the associated changes of the lesions more clearly compared to CT. On CT,all the involved paranasal sinuses invariably expanded.The bony walls of paranasal sinuses were compressed and remodeled with focal defect in 28 cases,mostly in the medial wall of the maxillary sinus (21 cases).Bony scelerosis of the residual walls of paranasal sinus were found in 8 cases.The lesions demonstrated well-defined margin and heterogeneous density with phlebolith in 10 cases.Postcontrast CT showed marked inhomogeneous enhancement in 16 cases.On MR T_1WI,canernous hemangioma showed hypointense signal compared to brain in 4 cases and isointense signal in 14 cases.On T_2WI,the lesions revealed heterogeneous hyperintense singal in 16 cases and isointense signal in 2 cases with multiple hypointense foci.Postcontrast MR imaging demonstrated marked inhomogeneous enhancement in these cases,honeycomb-like appearance in 8 cases and variegated appearance in 10 cases.The feature of progressive enhancement was found on dynamic contrast enhancement of MRI in 8 cases.Conclusions The characteristic bony change together with phlebolith can suggest the diagnosis of cavernous hemangioma in paranasal sinus on CT.The heterogeneous hyperintense singal on MR T_2WI,progressive enhancement and honeycomb-like or variegated appearance on postcontrast MRI were also the characteristic findings of cavernous hemangioma in paranasal sinus.Combination of CT and MRI findings can provide more accurate information for the diagnosis and therapy of cavernous hemangioma in paranasal sinus.
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Objective To study the CT and MRI findings of osteosarcoma in paranasal sinus and evaluate their clinical value.Methods All 9 cases of osteosarcoma were verified by histopathology.Imaging data were analyzed retrospectively.Results The lesion occurred in maxillary sinus in 5 cases,in ethmoid sinus in 3 cases and in sphenoid sinus in one case.Primary osteosarcoma was found in 7 cases.Secondary osteosarcoma occurred from fibrous dysplasia and ossifying fibroma each in one case.On CT,the involved areas revealed bony destruction associated with ill-defined and irregular soft tissue mass.The lesion showed heterogeneous density with minimal or massive tumor bone formation,cloud-like in 3 cases,ivory-like in 2 cases,spicule-like in 2 cases,cloud- and spicule -like in one case and spicule- and ivory-like in one case.Postcontrast CT showed mild to moderate inhomogeneous enhancement in 3 cases.On MR T_1 WI,the lesions showed hypointensity compared to brain in 5 cases and iso-intensity in 2 cases.On T_2WI,the lesions showed heterogeneous hyperintensity in 4 cases and isointensity in 3 cases with marked hypointense foci which corresponded to tumor bone on CT.Postcontrast MR imaging demonstrated moderate to marked inhomogeneous enhancement in these cases.MRI showed accurately the extent and associated changes of the lesions.The lesions invaded the orbit,pterygopalatine and infratemporal fossae,skull base and extensive craniofacial structures in 5,4,3 cases and 1 case,respectively.Conclusion CT is the optimal modality in showing tumor bone of osteosareoma in paranasal sinus.MRI can demonstrate optimally the invading extent of the lesions.Combined imaging modalities can provide more comprehensive information for diagnosis and therapy of osteosarcoma in paranasal sinus.