The exploration of the chiasm and retrochiasmal visual pathways relies on magnetic resonance imaging. If a lesion of the optic chiasm is suspected, the millimetric acquisitions in T2 and T1 weighting with and without contrast infusion are carried out in the three planes.
There are two vaccines available in the UK-an oral vaccine and an injectable vaccine. Both vaccines stimulate your body to make antibodies against typhoid germs (bacteria). These antibodies protect you from illness should you become infected with typhoid bacteria.
The complete series of 4 vaccine capsules should provide protection against typhoid for up to 5 years. Another series of 4 capsules is then recommended every 5 years during possible exposure to typhoid. Your individual booster schedule may be different from these guidelines.