The diagnosis of pituitary adenoma includes three aspects: clinical symptoms + endocrine examination + magnetic resonance imaging 1. Endocrine examination: Increased prolactin (PRL) in pituitary prolactin adenoma, exceeding 10 times the normal value; increased growth hormone (GH) in pituitary growth hormone adenoma, exceeding the normal value; increased blood cortisol (F) in pituitary pro-adrenal hormone adenoma, increased adrenal hormone (ACTH) is increased.
MRI: (1) MRI of pituitary microadenoma: T1-weighted image shows that most microadenomas are low signal, a few are equal or high signal, and indirect signs such as pituitary stalk deviation and saddle subdivision can be seen. Gd-DTPA enhancement shows that pituitary tissues and adenomas do not strengthen synchronously, and generally pituitary tissues strengthen earlier than pituitary microadenomas.
(2) MRI of pituitary macroadenoma: T1-weighted image shows equal or low signal, T2-weighted image shows equal and high mixed signal. Cystic lesions, necrosis and hemorrhage within the tumor each show their signal characteristics.
(3) Pituitary stroke MRI performance: T1 and T2-weighted images can be seen as high signal, suggesting tumor hemorrhage, if T1-weighted image is low signal, T2-weighted image is high signal, suggesting intra-tumor infarction with edema.
3.Pituitary CT: Coronal scan, sagittal reconstruction and axial examination of pituitary gland can improve the detection rate of pituitary microadenoma. Signs of pituitary microadenoma: (1) Direct signs are hypodense areas in the saddle >3mm, a few are high density; while microadenoma with equal density needs to be diagnosed with indirect signs; (2) Indirect signs are pituitary height >7mm, saddle diaphragm is full or bulging, asymmetric; pituitary stalk deviation >2mm from the midline is more significant. Pituitary macroadenomas are mostly high-density signals occupying the saddle and may develop suprasellarly; there may be low-density signals inside the tumor, which are caused by tumor softening and necrosis, cystic change. Hemorrhagic foci are seen in pituitary strokes. If the tumor develops suprasellarly and affects interventricular foramen and III ventricle, obstructive hydrocephalus may appear. Enhanced CT scan shows homogeneous or peripheral enhancement of the tumor with clearer borders.