THE VALUE OF MRI IMAGING AND ITS SIGNIFICANCE IN THE DIAGNOSIS OF INVASIVE PITUITARY ADENOMA

Objective To assess the value and significance of MRI imaging in the diagnosis of invasive pituitary adenoma. Methods Twenty-nine patients with invasive pituitary adenoma confirmed by surgery and pathology were imaged with sagittal,coronal T_1WI,or coronal PDWI and T_2WI,sagittal,coronal or T_1WI after Gd-DTPA injection,spin-echo sequences,using 0.5 T MRI scanner.MRI findings were analyzed and compared with surgical and pathological results. Results The MRI appearance of the tumors was equal signal intensity in T_1WI,equal or high signal intensity in T_2WI,and even or uneven enhancement after Gd-DTPA injection.MRI findings included invasion of the sella turcica and adjacent bones,involvement of sphenoid sinus and cavernous sinus,encasement of internal carotid artery.Ten patients with grade-0 invasion on MRI were found to have non-involvement of cavernous sinus during surgery;14 cases with grade-1 invasion on MRI,three of them showed involvement of cavernous sinus and encasement of internal carotid artery;in 20 cases with grade-2 involvement of cavernous sinus on MRI,15 were confirmed by surgery;in nine cases with grade-3 invasion on MRI,eight were found to have invasion of cavernous sinus and lateral interspace of internal carotid artery;in five with grade-4 invasion on MRI,four had involvement of cavernous and encasement of internal carotid artery. Conclusion MRI is helpful in providing information on invasion of pituitary neoplasms for preoperative diagnosis,which is of great instruction significance for the management of the disease.