Bickerstaff's encephalitis is a rare inflammatory disorder of the central nervous system, first described by Edwin Bickerstaff in 1951. It may also affect the peripheral nervous system, and has features in common with both Miller Fisher syndrome and GuillainâBarrÃ© syndrome. 1  1 Signs and symptoms.  2 Pathophysiology.
Pathophysiology. Tears are produced in the lacrimal gland and drain through the upper and lower puncta into the canaliculi and then into the lacrimal sac and nasolacrimal duct (see Figure: Anatomy of the lacrimal system. ). Obstruction of tear drainage can lead to stasis and infection.
The lacrimal system consists of a superior and inferior puncta at the medial ends of upper and lower eyelids. These two drain into upper and lower canaliculi. These two canaliculi join to form the common canaliculus. This zone is known as the upper lacrimal system. The common canaliculus inturn leads into the lacrimal sac.