Okaps flashcards - glaucoma
(27 cards)
Name 2 RGC cells
M cells: large diameter axons, dim light. P cells: small diameter axons, color and fine detail
Blood flow to four layers of optic nerve
NFL: CRA, prelaminar: sort posterior, laminar: posteiror ciliary, retrolaminar: branches of meningeal and CRA
composition of vitreous
99% protein free, very high vit C, calcium is half of plasma, lactate in aquous is higher
where in the TM is resistance the greatest?
juxtracanalicular meshwork
cause of ACG in pt who underwent scleral buckle
anterior rotation of ciliary body
what drug when added to betaxol procduce and ocular hypotensive effect equivalent to timolol
dipivefrin
function of longitudinal and circular fibers
long: insert into scleral spur, affect outflow, circular: affect acomodation.
helmotz theory of accomodation
contraction of long pulls lens forward, shallowing AC. Contraction of circular relaes zonules, lens more spherical, more focusing power. Relaxation of circular fibers tightens zonules, streches lens, makes I tthinner
production of aqueous
by active secretion, Na/K pump and carbonic anhydrase
how to measure aquous humor
fluorophotometry, AC volume 250 ul, PC 60 ul
compositionof aquous
acidic 7.2, 15x more ascorbate, low protein, lower CA, phos, otherwise similar
outflow pathway
uveoscleral meshwork, corneal scleral, juxtacnalicular, schlemms collector channels, veins, SOV, cavernous inus
effect of cycloplegics on uvealscleral outflow
increases
ddx of blood in sclem’s cnal
elevated episcleral venous pressure, nevus of ota, NF, congenital ectropion uvae
IOP changes with
higer lying down than siting, lower after exercise.
extent of visual field
60 nasally, 75 omferopr; 100 temporally
goldman test size
I-V each increment doubles diameter, quadroulds area
goldman light filter
1-4 incrememnts to 5 db, a-e 1 db.
chromosome of pigmentary glaucoma
15
krunkenberg’s spindle
melanin phagocytized by corneal endothelium
causes of elevated episcleral venous pressure
CCF, sturge weber, NF, orbital mass, TED
plateau iris
deep central AC, shallow peripheral
mechanism of malignant glaucoma
entire AC shallow, has PI
RF for aqeuous misdirection
uveitis, angle closure, nanophthalmis, post op
