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.
Nasolacrimal duct. The nasolacrimal duct (sometimes called the tear duct) carries tears from the lacrimal sac of the eye into the nasal cavity. The duct begins in the eye socket between the maxillary and lacrimal bones, from where it passes downwards and backwards.