lacrimal gland
ducts in the palpebral acessory lacrimal gland merge with other ducts the cliber increases and emerge on the conjunctival surface with incidence of _______
.100mm2
the actions of secretogogues appear mediated through 3 pathways which are......
1) cAMP by b adrenergic & vipergic 2) diacyl glyceroldependent pathway- alpha 1 adrengeric 3) ca calmodulin diacylglyercol pathway activated by cholingernic
lacrimal gland blood supply from arterial side is by 2 artieries ___ and____ & one vien ______
1. lacrimal artery 2. internal maxillary artery 3. lacrimal vien
what are the two routes in which lacrimal glands can be reached
1. retro orbital plexus 2. directly to the lacrimal galdn via rami lacrimales without mixing with the retrooribal plexus
lacrimal gland develops near the ____ month of pregnancy but it is not functional till ___ weeks after birth
3rd month (feb for j sis) two weeks! then baby can cry sometimes it starts at two months
parasympathetic system in lacrimal gland pathway starts at pons--- to ____ cn to ____ parasympathetic fibers for the lacrimal gland are located where? parasympathetic fibers are responsible fore secretion and are the main contributor to______
7 (facial) pterygopalatine INSIDE THE ACINUS tear film
approximately ______ % of tears are normally drained through the lacrimal system while ___ percent _____
70-80% 25% evaporate
there is no __________ branch between the zygomatic nerve and _______ nerve as the old pathway suggested
ANASTAMOSING LACRIMAL NERVE
the final tear fluidis formed as a mizture of ___ rich cluid secreted by the main ___ cels and KCL rich fluid how is the secretory function of acinar cells is regulated by________ which is innervated by neurotransmitters such as ___
NA CL acinar autonmoic secretomotor innervation acetycholine and VIP, nonprinphrine, NPY
recent discovery is ___ plays a role in modulation of tear production
NO
does stimulation of the sympathetic nervous system change tear secretion?
NO it doesnt therefore if the superior cervical ganglion is destroyed secretion of the gland is unaffected
innervating structures (3) ABi where are nerve fibers found? where are nerve terminals found?
acinus blood vessels interstitium 1) nerve fibers are found in blood vessels and interstitium 2) nerve terminals are found in all three areas
acini are surrounded by loose ____ fibers, a capillary network, lymphatics, and rich vascular and____ supply
collagen nerve
fornix accessory lacrimal gland of krause is located in the __________ this gland is functionally and structrually similiar to the _____ gland
conjuctival fornix lacrimal gland
ampulla ____ causes contraction of ampulla which drives tears to the lacrimal sac
connects the horizontal and vertical compnents of the canaliculus. blinking
nasolacrimal duct is a _____ continuation of the lacrimal sac to the ________ of the nose
downward inferior meatus
the innervated structure, acinus has __ nerve terminals found next to ___ secreting cells. which are electron dense with ___ staining.
facial serous dark
There are two levels of secretion that parasympathetic controls, what are they? and what was recently found that changes tear secretion?
first order second order Nitric oxide
the lacrima gland is located in the____ for the lacrimal gland in the ___ bone and is divided into two portions ___ and ___ portion b the aponeurosis of the levator muscle. functionally it is ___ gland
fossa frontal orbital and palpebral one
caruncle
found nasal to the plica semilunaris this is glandular tissue covered in hair and contained sweat gland it is a round looking thin
what are the 3 forces that remove tears 1.______ which is 4x more likely in lower punctum 2.______ 3.______
gravity capillary attraction blinking
lacrimal sac what part of canaliculus is invovled where is lacrimal sac located
horizontal canaliculus leads from ampulla to lacrimal sac lacrimal sac is located at the fossa for lacrimal sac in the medial wall of orbit
punctum
is the opening where the tears drian into the lacrimal sac. there is a superior and inferior punctum
the lacrimal system consists of the _____ gland, the accessory____ and a ____ system
lacrima lacrimal glands drainage system from eyelid to nose
what is sjogrens syndrome
lacrimal gland dysfunction may indicate dry eye that can loose corneal transparency. could be caused by atrophy of lacrimal gland or neurological problem
there are no nerve terminals located in ___ cells because they are ___ innervated
myoepithelial cells directly
along the secretory cells are contractile cells called____ which are activated during ____ lacrimal activity
myoepthelial cells high
there are two levels of tear secretions 1. is ___ order secretion during normal activies 2. is ___ order secretion during____
normal high reflex tearing and crying
the tear is made up of 4 things NGGI
nutrients growth factors glycoprotiens immunoglobins
nasal sinuses are ___ from the nasal cavities
outgrowths
the orbital portion of lacrimal gland is superior larger portion and drains into ___ via ___ ducts
palpebral portion 12 main ducts
the nervous the nervous supply is innervated by parasympathetic- P sympathetic-S CN5 -neural nirtric oxide recently it showed that ___ identified in cell s in the pterygopalatine may play a role in modulation of tear production
parasympathetic:pterygoid palatine sympathetic: superiorcervical ganglion Nitric oxide
varying pathways to lacrimal gland but hte "revised pathway" by _____ has a scientific basis and is considered VALID this pathway says: the ____ fibers are delivered to the _____ in the rami lacrimales which enter through the _____ the rami lacrimales affect the galnd by innervating the _____
ruskell 1971 secretomotor lacrimal gland inferior orbital fissue acinus
the papebral accessory lacrima gland of wolfring is located in the ____ of the eylid and is structurally and ___ similiar to the lacrimal gland its secretion is ____ which forms the middle portion of the ____ tears. recent research with rabbits show extensive network in lid tarsal and orbital portions not in ______ the acini here ar located in the ___-
tarsal plate, lacrimal gland serous trilaminar tears marginal region subeithelial areolar stroma
where is the tear drainage apparatus located
the medial canthus
canaliculus what are the components what component lead to the ampulla the horizontal and vertical canalicul meet form the ____ in about __- percent of people they are two seperate glands
the tear passages from the puncta that have a vertical and horizontal components. the vertical part way to remember***VP ( vertical to puctum) Horizontal to HALs. like cough drop (horizotal to ampulla to lacrima) common canalicus 10%
what is the plica semilunaris
this is the human remnant of the third eyelid found in some animals it has sebaceous and sweat glands and located in media canthus
the lacrima glan with a acini with a central lumen leading to ____ which lead to ____ and empty into____
tuberacemose gland tubes intermediate ducts superior fornix