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.
Tetanus toxoid (TT), the vaccine that protects mothers and newborns from tetanus, is a detoxified version of the toxin (poison) that causes the disease. A fourth variety of vaccine, such as that for Haemophilus influenzae type b (Hib), uses only the components of the virus or bacteria that provoke an immune response.