Lecture 7: 12/7 Flashcards
list some functions of the ciliary body
accommodation, aqueous humor production, produces MPS
example of a DPA drug that acts on the ciliary body
cycloplegic, which temporarily paralyzes ciliary body so you can get better refraction
example of a TPA drug that acts on ciliary body
glaucoma drugs
describe how the ciliary body can be an “asymmetric girdle”
one side is more narrow, it is not the same width all the way around, and it is a band that runs interior to the anterior portion of the eye
ciliary body narrow portion (nasal side) width is
5.5mm
ciliary body broader portion (temporal side) width is
6.5mm
average width of ciliary body is
6.0mm
anatomy of apex of ciliary body
points posteriorly and continuous with choroid
anatomy of base of ciliary body
facing towards center of the cornea
the base of the ciliary body’s outer end is attached to the:
scleral spur
the base of the ciliary body’s inner end is where?
it jets out into the vitreous chamber (posterior of eye)
anatomy of the external surface of the ciliary body
is against the sclera
the periciliary is continuous with the perichoroidal space
anatomy of the internal surface of the ciliary body
meets up with the retina, and the retina “overlaps” the ciliary body like the wave on sand
posterior view of the ciliary body has what 2 zones
- pars plana (flat)
2. pars plicata (folded)
what are the fine striations in the pars plana called?
stria cillaris of Schultz
what width does the pars plana take up from the average 6mm
4mm
which is most posterior out of the two zones of the ciliary body?
pars plana
what is the ora serrata
the junction where there are some parts of the retina and some parts of the ciliary body, scalloped edge
the scalloped extension of the ciliary body in the ora serrata is called
the bays of ciliary body
the tooth-like extensions of the retina at the ora serrata are called the
dentate processes (of the retina)
the pars plicata makes up ____mm of the 6mm wide ciliary body
2mm
the anterior end of the ciliary body on the pars plicate is continuous with the
iris (of the vascular tunic)
how many folds are in the pars plicata and what do they look like?
they have a white stripe on top of the folds
70-80 folds
the “folds” of the pars plicata (called the ciliary processes) is where the ____ attach
-zonules attach (zonules is where the aqueous humor is produced)
it is from the surface of the ___ ____ that the aqueous humor is secreted
ciliary processes
the outer edge of the surface of the pars plicata is attached to the:
scleral spur
list of the 6 layers of the ciliary body
- ciliary muscle
- vessel layer (stroma)
- basal lamina
- pigment epithelium of ciliary body
- non-pigmented epithelium of ciliary body
- internal limiting membrane
which ciliary body layer is a continuation of Bruch’s?
basal lamina
the ciliary muscle layer is what type?
smooth muscle
the ciliary muscle layer is controlled by
the autonomic nervous system (ANS), the parasympathetic division
what is the origin of the ciliary muscle layer?
the ciliary tendon (which is attached to the scleral spur)
what is the bundle arrangement of the ciliary muscle layer from external to internal?
- longitudinal muscle
- radial muscle
- circular muscle
the origin of the longitudinal, radial, and circular muscle groups are the
ciliary tendon
attachment of the muscle bundles in the ciliary muscle is in the form of a V shape. where does the apex and base face?
the base facing the scleral spur and the apex facing posteriorly
which of the three muscle bundles in the ciliary muscle layer ends in muscle stars in the suprachoroid?
longitudinal
what muscle bundle in the ciliary muscle layer is internal to the longitudinal and has the base of the V which is wider and tend to run at an oblique angle to the optic axis?
radial
where is the insertion of the circular bundle of the ciliary muscle?
into the anterior ends of the ciliary processes
the muscle bundle that has two arms of the V shaped bundle arising from very wide attachments to the ciliary tendon, and that run almost parallel to the equator
circular
the 3 muscle groups in the ciliary muscle have what action when they contract?
causes the ciliary body to move forward and at the same time inward towards the center of the eye
axipetal motion has what action on the zones and ciliary body?
it causes a reduction in tension on the zonules causing the elastic lens capsule to contract -> lens becomes more spherical
increased dioptric power results from the ______ curvature of the lens surfaces
increased
describe the main components of the vessel layer (stroma) of the ciliary body
arteries, capillaries, veins, in a loose connective network
what are the two vessel that supply blood from the vessel layer of the ciliary body?
- long posterior ciliary artery
- anterior ciliary artery
the two vessels, the long posterior ciliary artery and the anterior ciliary artery, form a plexus called
major arterial circle of the iris
describe the path of a vessel from the major arterial circle
they run posteriorly and enter the ciliary processes and form unusually rich capillary beds in the ciliary processes
where does venous drainage occur from the stroma?
from the stroma is posterior to the choroid
the elastic layer of Bruch’s membrane gradually tails off into fine fibrils which lose themselves in what layer in the basal lamina?
in the stroma of the vessel layer in the area of the pars plicata
the inner collagenous zone of Bruch’s thickens at the ora serrata and extends into the
basal lamina, pars plicana (similar to elastic layer)
the basement membrane of the pigmented epithelium of the ciliary body is an anterior continuation of:
the basement membrane of the retinal pigment epithelium
the basement membrane of the pigmented epithelium of the ciliary body continues on to the
root of the iris
