Imaging featuresIn recent years, imaging techniques such as CT and MRI have improved significantly, and the diagnostic accuracy of saddle-nodal meningiomas has increased significantly. CT: On CT, it is mainly a round or round-like, homogeneous occupying lesion at the base of the saddle node, which may be isointense or dense. On enhancement scans, the mass is usually uniformly enhanced, and sometimes abnormally thickened blood supply arteries can be seen around the tumor. Multilayer spiral CT 3D angiography can not only fully reveal the imaging features of saddle node meningioma, but also can understand the blood supply of the tumor. MRI: In MRI scan, saddle node meningioma shows isosignal on T1WI and equal or slightly high signal on T2WI. The pituitary gland is mostly intact with homogeneous signal, and the pituitary stalk is well defined. The saddle diaphragm with low signal separates the tumor from the pituitary gland. On enhancement scans, the tumor is clearly enhanced, and linear enhancement of the basal dura is seen on T1 images (meningeal tail sign). The presence of this feature is highly supportive of the diagnosis of meningioma. It has been reported in the literature that 52%-78% of paragangliomas in the saddle have a meningeal tail sign, with a diagnostic specificity of 92%-94.02%. MRI is significantly better than CT in localizing and qualitatively diagnosing meningioma in the saddle node and showing the relationship between the tumor and adjacent tissues, showing the dural attachment points, subacute hemorrhage and cystic changes, as well as the vascularity in and around the tumor, providing favorable value for surgery. It is often difficult to distinguish meningioma from pituitary tumor in the saddle area. However, MRI is less sensitive to calcification and bone changes, and the nature of meningioma can be determined by osteophytes or osteolysis on CT bone window scan. Therefore, simultaneous examination of CT and MRI is currently advocated to help localize and characterize the tumor, understand the relationship between the tumor and surrounding tissues, and provide detailed information for diagnosis and treatment. (3) Cerebral angiography: angiography can show the blood supplying arteries and returning veins of the tumor and clarify the adjacent relationship between the tumor and the surrounding important blood vessels, which is helpful for preoperative assessment of the difficulty of surgery and formulation of surgical plan. (4) X-ray plain examination: some of them can show the osteophytes of saddle nodes and slight resorption of anterior bed prominence; the butterfly saddle is enlarged and the saddle base is thinned. It is rarely used in clinical work at present.