 All right, we're gonna get started. I am the first one of this morning's lectures And I'm talking about an iris anatomy. So there's just a Histologic picture of the iris. So there's two ways to think of anatomy. There's the clinical anatomy and then the The histological anatomy. So first let's talk about the clinical anatomy. There's two main zones the pupillary zone and that Contains the, let's see which one's the laser again. There we go. The pupillary zone, which contains the rough and the reflected area of posterior pigmented Area, and then you have the ciliary zone, which is on the outside of the rough It contains iris crypts and they're separated by this collaret, which represents the blood vessels running through the iris So the other way to look at it is more histologically. There's five layers that we Classically talk about the anterior limiting layer or the anterior border and that is Interrupted by a connective tissue that burns with ciliary body, and then there's a stroma which is sort of the meat of the iris that has melanocytes, the vessels, and Different things that we'll talk about more detail. Then the muscular layer There's the smooth muscle at the pupillary margin and the smooth muscle deep in the iris stroma. You have the anterior pigment epithelium and posterior pigment epithelium Here's kind of the cartoon version of this So you can see All right, but this anterior border the stroma with all blood vessels and Then the muscles and the posterior pigmented area So the anterior border is a condensation of fibroblasts and melanocytes. It's really really dense where you have the crypts it is absent and from what I read the reason for that is so that the Aqueous humor can more fully bathe the stroma in those those crypts The stroma itself contains pigmented cells, melanocytes, clumped cells, fibroblasts, collagen, hyaluronic acid, blood vessels on the nerves Next we have the muscular layer This is kind of The bulk of the iris anatomy we get in medical school is that there's the stinctor pupillary and the dilator The dilator is more central, more medial and the stinctor is more medial and the dilator is more lateral and you can see in this drawing the way the fibers run So smooth muscles, autonomic innervation and they're derived from the anterior pigment layer of the iris So I'm just going to touch on this a little bit I think it's going to be explained in more detail when we talk about some of the abnormal findings, but on the dilator muscles innervation Synthetic innervation, alpha one-adrenergic stimulation starts in the ipsolatohypothalamus synapses to the T1 level spinal cord and then it travels from spinal cord over the pulmonary apex, which is something I always think about with thoracic outlet syndrome and things like that and then it runs up the superior cervical gain, nanglion and Runs it along the internal crowded plexus through the cavernous sinus and then through the Ophthalmic division of cranial nerve 5 to the dilator muscle and then there's also some parasympathetic innervation. That's inhibitory The stinctor muscle is parasympathetic Mostly with the musculinic receptors starts in the editor Westphal nucleus Runs through cranial nerve 3 through the cavernous sinus the superior oblique branches to the superior oblique muscle and synapses in the ciliary ganglion and it then Terminates the short ciliary nerve to the ire stinctor. You can see the sympathetic innervation there that helps inhibit the stinctor muscles So the anterior pigment myopathylium specialized myopathylial cells The apexes of the anterior and posterior face each other and the bases face out It's continuous with the pigmented epithelium of the ciliary body one thing Dr. Manlis always talks about in path reads is The way to tell between the iris and the ciliary body is the iris has two pigmented layers that you can't differentiate Whereas the ciliary body just has the one so this is continues with the pigment and ciliary body layer Then you have posterior pigment epithelium This is the part you see coming through the pupillary rough that I on especially people with like called Pupillary atropian where you can see it coming posterior to anterior and So in summary you have five layers that important to keep in mind when you're Thinking about iris anatomy the anterior border layer the iris stroma the muscles and the anterior posterior pigment epithelium