The patient is automatically moved head first into the CT gantry, and the x-ray tomogram is acquired. Now the patient is automatically moved through the PET gantry, which is mounted in parallel with the CT gantry, and the PET slices are acquired. The patient may now leave the device, and the PET-CT software starts reconstructing and aligning the PET and CT images.
Diagnostic Procedures. Three common diagnostic procedures, tonometry, visual field tests, and ophthalmoscopy, enable ophthalmologists to screen patients for glaucoma. To make a definitive diagnosis, ophthalmologists often use all 3 procedures as part of an overall eye examination. The procedures are simple, relatively quick, and virtually painless.
1 Eye pressure. 2  Tonometry measures the pressure in the eye (intraocular pressure, or IOP). 3  Vision tests. 4  These include tests to check for visual acuity and loss of side and central vision (perimetry testing).arly detection and treatment of glaucoma are important for controlling the condition and preventing blindness. A doctor evaluating possible glaucoma will take a medical history and do a physical exam. If your doctor suspects glaucoma, he or she will refer you to an eye specialist (ophthalmologist).