Meningioma of the lateral 1/3 of the pterygoid crest. The lateral type of meningioma of the pterygoid crest has late onset of symptoms, the tumor occurs in the large wing of the pterygoid bone and causes bone growth in the posterior lateral wall of the orbit and temporal area, resulting in orbital shrinkage, or the tumor invades directly into the orbit resulting in proptosis of the eye. What are the examination methods of orbital shrinkage? 1.CT scan The tumor can be seen as a spherical growth centered on the pterygoid crest, with clear boundary, and the tumor shadow is obviously enhanced after contrast enhancement. 2.MRI scan MRI is meaningful for the diagnosis of this disease, MRI can show the relationship between tumor and pterygoid wing and orbit, and the bone destruction. Especially for medial type of pterygoid crest meningioma, MRI can also provide the relationship between the tumor and internal carotid artery, sometimes the tumor wraps the internal carotid artery or the tumor is attached to the cavernous sinus, all these conditions have important reference value for surgical removal of the tumor. The enhanced MRI image is clearer. 3.Cerebral angiography Nowadays, it is not used for localization diagnosis, but it can provide the blood supply artery of tumor and the adjacent relationship between tumor and main blood vessels. In medial pterygoid crest meningioma, the blood supply artery mainly comes from the branch of ophthalmic artery, and if the tumor develops in the anterior cranial fossa, the blood supply of anterior septal artery can be seen. In lateral type pterygoid crest meningioma, the blood supply mainly comes from the external carotid artery branches, such as the middle meningeal artery, which appears as typical radial tumor vessels, and the tumor staining is more obvious in the venous stage than the arterial stage. The middle cerebral artery is generally elevated in the lateral image due to tumor compression. If external carotid artery supply is seen at the same time of cerebral angiography, vascular embolization can be performed at the same time to reduce surgical bleeding.