Week 5

Cerumen impaction

-Accumulation of cerumen, sloughed epithelial cells, and hair (cotton swab use, hearing aid use) -Patients: elderly patients, mentally retarded, children -Symptoms: pain, fullness in ear, tinnitus, dizziness, hearing loss, chronic cough -Diagnosis: direct visualization through otoscope TREATMENT -gentle cleaning with water/saline at body temp. Contraindicated with perforated eardrum, severe otitis externa, foreign objects. -manual removal with curette. -Ceruminolytics (oil/water based)

Monochromancy, Dichromancy, protanopia, deuteranopia, tritanopia, anomalous trichomancy, protanomaly, deuteranomaly, tritanomaly. ACHROMOTOPSIA

-Achromotopsia: total color blindness. Absence of 2 of the 3 types of cones

Acoustic Neuroma

-Actually a schwannoma of the 8th cranial nerve -arises in vestibular portion of nerve VIII, so actually a vestibular schwannoma PATH: a benign neoplasm of schwann cells ---loss of expression of the NF2 gene product: merlin, causing proliferation SX: hearing loss, tinnitus, vertigo, dizziness, loss of balance, headache, facial weakness, facial numbness or numbness in one ear, facial pain or pain in ear HISTO -Antoni A areas (verocay bodies). more cellular -Antoni B areas. less cellular TX: watching waiting, sterotactic radiosurgery, surgery

Bright light adaptation

-Bright light leads to increased channel closure and decreased intracellular Ca++ -Ca++ inhibits guanylyl cyclase, so decreased levels of Ca++ leads to increased synthesis of cGMP and increased channel opening and decreased hyperpolarization. -Higher levels of light are then needed to close the channel and hyperpolarize the membrane

Layers of Retina, define nuclear and plexiform

-Choroid 1) Pigment Epithelium 2) Layer of rods and cones 3) Outer limiting layer 4) Outer Nuclear layer 5) Outer Plexiform layer 6) Inner nuclear layer 7) Inner plexiform layer 8) Ganglion cell layer 9) Nerve fiber layer 10) Inner limiting layer -Vitreous LIGHT: 10-9-8-7-6-5-4-3-2-1 Convergence of signal: 1-2-3-4-5-6-7-8-9-10 3NUCLEAR LAYERS (cell bodies): outer (nuclei of rods and cones), Inner, and Ganglion -2 PLEXIFORM (synaptic zones)

Diabetic Retinopathy

-Disorder of Retinal Vessels -Degree of disease is nonlinearly related to age of onset (earlier greater risk), blood sugar control, other CV risk factors, ie. obesity, hyperlipidemia, smoking, diet, exercise -leading cause of severe visual loss in working age population PATH -pericytes die leading to micro aneurysm formation and thrombosis

Optic Disc and Fovea Centralis

-Exit of ganglion cell axons -No photoreceptors, interneurons, or ganglion cells -Lamina cribosa of sclera -Central artery and vein of retina FOVEA CENTRALIS -Surrounded by macula lutea (yellow spot) -temporal side of optic disc -many cones -high quality vision -midget bipolar cells (contain midget ganglion cells)

Diabetic Retinopathy locations of damage

-Hard exudates occur due to edema. This fluid is removed leaving behind the protinatious material INTRARETINAL H. in the deeper retinal layers (outer nuclear layer, photoreceptor cell layer) creating dot-plot hemorrhages and flame shapes EXUDATES: same as intraretinal COTTON WOOL SPOTS -"soft exudates". superficial. Suggests ischemia

Chondrodermatitis Nodularis Helicus

-Mimicker of basal cell and SCC. Grows to cartilage -middle-aged to elderly men -PATH: pressure to ear, sun exposure, autoimmunity SX: painful rapidly enlarging ulcer on helix of ear, which suddenly stops growing and remains stable TREATMENT: avoid pressure on side, excision -no malignant potential

Phototransduction and Retinal

-Outer segment membrane contains a trimeric GPCR and a signal transduction cascade that results in hyperpolarization -Retinal receptors do not have action potentials, but rather have graded changes in membrane potential leading to graded neurotransmitter release onto postsynaptic neurons (bipolar and horizontal) RETINAL: derivative of Vitamin A. 11-cis retinal is initiated by absorbing a photon to become trans

Visual Field to retinal field, subdivisions of LGN

-The visual field is flipped up for down and left for right on the retinal field -Optic nerve->optic chiasm-> left or right optic tract -Magnocelluluar (1,2) project to dorsal aspect. Parvo-ventral -Magnocellular are sensitive to visual input linked to movement and contrast -Parvocellular are responsible for high acuity vision, color vision, and visual input related to shapes

Otoscerlosis

-abnormal bone deposition in middle ear around the rim of the oval window PATH: fibrosis leading to bony overgrowth, there is familial connection (AD) SX: progressive hearing loss over decades DX: ruling out other causes of hearing loss, referral to audiologist TX: hearing aid, stapedectomy

Ear

-ear wax secreting ceremoneous glands Middle ear is comprised of oscicles and presents sound to the ovale window

Sickle Cell Vasculopathy

-inherited condition creating sickle shaped hemoglobin. Results in blockages and ischemic changes. Specific genetic change is mutation of thyamine for adenine on 6th codon in hemoglobin (GAG to GTG) -In hypoxic conditions sickle hemoglobin becomes insoluble to shape change -Results in Vascualr occlusion at all levels in the eye from conjunctiva to retina, choroid, optic nerve SALMON PATCH HEMORRHAGE OR BLACK SUNBURST -PROLIFERATIVE ---Peripheral arteriolar occulsions ----Peripheral Neovascular proliferation in Retina ---Vitreous Hemorrhage/Retinal detachment

LGN projections to primary visual cortex

-portion of LGN where superior visual fields are mapped (inferior retinal field) loop around the lateral aspect of the posterior and inferior horns of lateral ventricle and project to the ventral aspect of the calcarine sulcus -"Geniculocalcarine tract" -These green projects are termed "Meyer's loop"

Advanced Diabetic eye disease

-pre retinal hemorrhage -vitreous hemorrhage -traction in RD -Rubeosis Iridis -Neovascular Glaucoma

Otitis Externa and complications

-swimmers ear -Trauma to skin or ear canal or moisture leading to bacterial infection by pseudomonas, staphylococcus, streptococcus species or by fungi Symptoms: fullness, pain (particularly on movement of tragus), hearing loss, purulent discharge, pruritis TREATMENT -avoid trauma and water (no swimming). Hydrocortisone/neomycin drops COMPLICATIONS -chronic otitis externa -malignant otitis externa: immunosuppressed (chemotherapy, diabetes, HIV). Manifests as a fungal infection. Mortality 50%

transduction of the signal to the photoreceptor

-takes picoseconds -Opsin 3(degree) changes take around one millisecond -After one minute, all-trans retinal and opsin separate. All-trans retinol is enzymatically converted back to 11-cis retinal and attaches to an empty opsin and returns to the outher segment disc membrane to begin cycle again

Meniere's Disease

-vertigo of at least 20 minutes -hearing loss -tinnitus -aural fullness PATH: excess fluid (endolymph) in membranous canals TREATMENT -acute: meclizine, diazepam Long term: diuretics, gentamicin, corticosteroids, limit salt and meal size. Surgery

Gross anatomy of eye

3 LAYERS -SCLERA--> cornea UVEAL TRACT -Choroid-->ciliary body --> ciliary muscle (anteriorly)--> stroma of iris RETINA (Extension of CNS) -Rods, cones, bipolar cells, horizontal cells, amacrina cells, ganglion cells ANTERIOR CHAMBER POSTERIOR CHAMBER -aqueous humor (ciliary epithelium produced) -Post chamber -> Iris -> ant chamber -> canal of Schlemm ---Vitreous humor: 99% water, 1% collagen and hyaluronic acid MACULA: high density of cones and high visual acuity

Photoreceptor cells

9+0 microtubule arrangement RODS -Outer segment is cylindrical -Axon (inner rod fiber) terminates as a rod spherule -Contain photopigments -Contain Rhodopsin (night vision - low light) CONES -Outer segment is conical -Axon (inner cone fiber) terminates as a cone pedicle -Contains Iodopsin and photopigments (red, green, blue)

Papilledema

A specific form of optic disc swelling or edema caused by increased intracranial pressure (ICP)‐no other etiology for this terminology. • Bilateral Disease • Often presents with no Visual Symptoms or may present with Intermittent Transient Visual Loss. • Axoplasmic Flow stasis in nerve fiber layers in setting of increased ICP causing edema of optic nerve head. • Any cause of increased ICP can cause this: Tumors, Hemorrhage, Idiopathic elevated ICP (Pseudotumor Cerebri). -May occur acutely or over weeks. Untreated will lead to optic atrophy

Adjustment of lens for near vision

BASICS: cornea is 2/3rds of refraction and lens is 1/3rd FAR -Lens is flattened to facilitate far vision ---Ciliary muscles relaxed. Zonular fibers are stretched (taut). Image focused on the retina. Near objects would be "focused" behind the retina NEAR -ciliary muscles contracted. Reduced tension in zonular fibers -Lens becomes convex

Cherry Red Spots in Macula

Descriptive term of red central choroid showing through the surrounding opaque NFLayer of fovea/macula area. Fovea is an area with no overlying inner retinal layers so choroid shines through. ‐Unilateral etiology from central retinal artery occlussion. NFLayer edematous from ischemia. ‐Bilateral from deposition of gangliosides in ganglion cell layer (NFL) surrounding fovea centralis in patients with lipid storage diseases.

Emmetropia, Hypermetropia, Myopia, Astigmitism

Emmtropia: image properly focused. Single plane on retina HYPERMETROPIA: focal plane behind retina MYOPIA: focal plane in front of retina ASTIGMITISM: Cornea does not have spherical shape, instead ellipsoid. Image not focused on single focal plane

Homonymous, Heteronymous, Hemianopia, Quadrantanopia and cuts at various locations on nerve

Homonymous: similar loss of visual fields for both eyes -Heteronymous (non-homonymous): non-overlapping visual field losses in both eyes -Hemianopia: loss of half a visual field -Quadrantanopia: loss of a quadrant of visual field

Layers of Retina

INNER NUCLEAR: cell bodies of interneurons (Muller cells) -Nuclei of horizontal cells distal; bipolar cells middle; amacrine cells proximal -Bipolar cells project to the second synaptic zone INNER PLEXIFORM LAYER -Bipolar cells terminate on amacrine and ganglion cells -Processes of amacrine cells spread laterally GANGLION CELL LAYER NERVE FIBER LAYER: axons from ganglion cell converge towards optic disc INNER LIMITING MEMBRANE: Basal lamina between vitreous and ends of Muller cells -Cell bodies of ganglion cells (dendrites in inner plexiform; axons leave as optic nerve)

Treatment for Sickle Cell Retinopathy

Much like DR with laser photocoagulation for ischemic areas • Vitrectomy for Vitreous Hemorrhage/Retinal Detachment • Monitor IOP‐Higher can lead to further perfusion issues with sickle rbcs

2 types of Diabetic retinopathy

NONPROLIFERATIVE (NPDR): earliest stage with vascular incompetence, macular edema develops along with hard exudates in macula. Leading cause of visual loss in diabetics PROLIFERATIVE: widespread iachemia as vascular disease progresses with subsequent proliferation of neovascularization from VEGF. These vessels haphazard, and fragile break and cause intraocualr hemorrhages and retinal detachments. Leads to vitreous hemorrhage -----Hard exudates tend to be around the fovea

Treatment of DR

NPDR with macular edema treated with either focal argon laser to dry up fluid and seals leaks or intravitreal injections of anti-VEGF or steroids -PDR treated the same plus Pan retinal photocoagulation to limit the retina production of VGEF and reduce risk for proliferative disease. May also treat with anti-VEGF injections Intraocular surgery for retinal detachment, nonclearing hemorrhages STRICT BLOOD SUGAR CONTROL AND REDUCE CV RISK FACTORS

Glaucoma

OPEN ANGLE normal anatomy of the eye with a clear pathway for fluid flow, however in the collector channels for outflow, the trabecular meshwork and Schlemm's canal, there is a blockage which creates elevated IOP. Insidious onset‐usually completely painless • Elevated IOP causes damage to optic nerve through death of ganglion cells in characteristic fashion • Lose peripheral vision first and central last • Patient can have no symptoms until vison is lost centrally (by then it is too late) -More prevalent as we age NARROW • Narrow angle has anatomic blockage with a narrowing of the approach to the collector channels resulting in elevated IOP. -May be acute onset or chronic. Acute is heralded with severe eye pain, red eye, halos around lights, loss of vision, and fixed mid-dialted pupil often with steamy cornea. Medical emergency TREATMENT -immediate lowering of IOP with meds -Peripheral Iridectomy, laser or surgical -Observe to monitor IOP reduction

Otitis Media, complications

PATH: obstruction of eustachian tube leads to effusion, which becomes a nidus for bacterial growth (pneumococcus, Haemophilus, Morazella) -RIsk factors: Age, URI, fall/winter, bottle-feeding, pacifier use, smoking in household, daycare SX: earache/fullness, otorrhea, decreased hearing, fever, pulling at ear, irritability PE: bulging tympanic membrane TREATMENT -amoxicillin (less than 6 months, greater than 2 years) with observation an option -Analgesics COMPLICATIONS -perforation leading to cysts (cholesteatoma) -infection by Pseudomonas aeruginosa, staph aureus, or fungus. Mastoiditis and intracranial abscess

Color Vision

Rods: rhodopsin, with an absorbance maximum at about 496 nm. Chromosome 3 CONES -Blue photoreceptor with an absorbance max= 419nm. Short wavelength or "S cone". virtually absent from the fovea. CHROMOSOME 7 -green photoreceptor with an absorbance max= 531nm. medium wavelength or "M cone" X CHROMOSOME -Red photoreceptor with an absorbance max= 559nm. Long wavelength or "L cone". X CHROMOSOME ---The ratio of M to L varies in people, but acuity doesnt -The receptors have many AA differences (besides red/green), and these differences tune the cis-retinal absorption

Scotopic vision, Mesotopic vision, and photopic vision

SCOTOPIC: vision under extremely low light conditions. Rod vision exclusively, with no color perception and decreased acuity MESOTOPIC: vision under low light conditions, star light/moonlight. Predominantly rod activity but above the lower limits of cone activity PHOTOTOPIC: vision under indoor lighting and sunlight. Above rod saturation and in the range of best acuity. Upper limits induce bleaching of photoreceptors (snow blindness)

Occipital lobe projections (v3, v4, v5 function)

Secondary and tertiary visual cortex also referred to as visual association cortex and extrastriate cortex LGN->V1->V2-> V3 and V5

Basal cell carcinoma pic

gross: pearly papule -growth from basaloid layer of epidermis

Squamous cell carcinoma pic

invades underlying dermis -sun exposure and immunosupression -ulcerated nodule

Cells of Retina (photoreceptor cells, conducting neurons, association neurons, supporting neuroglial cells) and Muller Cells specifically

photoreceptor cells: rods and cones conducting neurons: bipolar cells and ganglion cells association neurons: spread laterally...horizontal cells and amacrine cells supporting neuroglial cells: Muller cells MULLER: nuclei in inner nuclear layer. Extend to outer limiting membrane and inner limiting membrane -Type of glial cell. Function as mechanical and metabolic support. -Microglial cells present in all cell layers as well

Age related macular degeneration

• Affects central vision generally in people over 60 yrs old. • Leading cause of irreversible blindness in developed countries. • Affects 12% of people over the age of 80 • Prevention is improved by exercise, eating well, not smoking • Comes in two forms, Dry (90% of cases) and Wet types PATH • Dry is a painless irreversible death of photoreceptors centrally in the macula • Further, Dry is degeneration of the Choriocapillaris, and retinal pigment epithelium, two layers vitally important for the health of the photoreceptors • Dry is associated with drusen, or subretinal deposits/pigment which continue to worsen and lead to slow progressive central visual loss. This is the most common type. • Wet is characterized by the development of subretinal neovascularization with bleeding and central visual loss, often acutely. Related to vascular endothelial growth factor (VGEF).

Band Keratopathy

• Band of calcium salt deposition in the interpalpebral fissure in the subephithelial space in cornea • Etiology variable: Can be seen in the setting of increased elevated serum calcium/phosphate, ie hyperparathyroidism, sarcoidosis, renal failure May also occur when corneal surface ph rises, and changes the solubility of the salts in the tear film, resulting in pptn. Occurs in chronic inflammation, ie uveitis, end‐stage glaucoma, pthisis bulbi Silicone oil in AC in eyes from complex RD repair Treatment • May chelate with EDTA and remove the calcium/phosphate salts but will recur if inciting event remains • May improve vision/ cosmetics

Pseudopapilledema, optic disc swelling

• Bilateral or Unilateral presentation. • Pseudo ‐papilledema presents with similar findings of optic disc swelling and can appear identical to true Papilledema, but is NOT caused by increased ICP. • May present with no visual complaints Host of inflammatory, infiltrative or infectious processes including: Syphillis, Lyme disese, cat ‐scratch disease, Inflammatory examples: Optic Neuropathy, Optic neuritis, Diabetic papillitis, Sarcoid, Infiltrative: Leukemia, Optic nerve tumors, Optic disc drusen

Cotton Wool Spots and Optic Atrophy

• Cotton wool spots are areas of retinal opacity from accumulation of axonal cytoplasmic debris from disrupted flow in a number of retinal ganglion cells resulting from ischemic insult - closure of a retinal arteriole, ie vascular disease such as DR or HTN. Small scotoma for patient. -Etiology related to ischemic insult to inner retinal layers and ganglion cells. Multitude of causes including diabetes, hypertension, vascular occlusion and others. Results in permanent loss of function of those ganglion cells, contributing to optic atrophy from the loss of these ganglion cells. • Optic Atrophy is secondary to death of a multitude of retinal ganglion cells that show up as a pale optic nerve. Visual loss is significant. May be from direct optic nerve disease or secondary to other processes.

Optic Atrophy

• Etiology is anything that compromises ganglion cell function on a large scale. Includes a host of inflammatory, Infiltrative, and Ischemic causes, local and systemic. • Vascular diseases such as diabetes, GCA, NAION • Infiltrative such as local tumors/leukemia • Inflammatory and Infectious • Toxic and nutritional causes • Hereditary • Workup is extensive

Phthisis Bulbi

• Final stage of an eye subject to any circumstance that resulted in complete loss of function, whether it be from trauma or disease‐end stage • Soft, shrunken, disorganized globe, atrophic and blind. • Usually painless or can be very painful all of a sudden years after onset • May harbor tumors, ie RB, Melanoma • Treatment options include prosthesis &/or enucleation

Infectious Keratitis

• Inflamed, painful process involving the Cornea • May be viral, bacterial, fungal, parasitic • Most often presents with pain, conjunctival injection, photophobia, and possible blurred vision • Exam shows inciting agent, ie ulcer/infiltrate from bacteria; multiple infiltrates from fungus in a quieter eye; dendrite (herpes) or nothing in viral • Culture/ RIA • Treatment includes ABX, antiviral, antifungals, etc • May result in visual loss from scarring

Retinitis Pigmentosa

• Most common cause of inherited blindness in 20‐60 yr olds in the world. Primarily affects peripheral vision • Degenerative disease with variable degree of penetration affecting primarily the rod photoreceptors thereby limiting vision in dim light situations • Loss of vision is gradual and affects peripheral vision primarily but can result in blindness • Inheritance is varied including X‐linked recessive patterns (most severe), but also with dominant and recessive patterns • Disrupted Rhodopsin protein DIAGNOSIS/TREATMENT • Electroretinophraphy (ERG) is the definitive test showing delayed electrical response in rods • Family history • Bone spicule formation on exam • Constricted visual field, progressive • No known treatment, but supplemental Vit A, may slow progression

Retinoblastoma, from what cells, chromosome

• Most common intraocular malignancy of childhood. • Arises from photoreceptor cell layer. Hereditary form (approx. 50% of cases) arise from mutation on chromosome 13, RB1 tumor suppressor gene. • Almost exclusively found in young children < 3 • Inherited forms more likely to be bilateral • Signs/Symptoms: Leukocoria (white pupil/reflecting tumor), red irritated eye with glaucoma, squint, strabismus and poor vision • Note pseudoleukocoria occurs with just the right angle of a picture reflecting the optic nerve TREATMENT • Goal is to preserve life and then VA • Spread is through the optic nerve to brain • Most common is chemotherapy • May use brachytherapy (radiation), thermodestructive, photocoagulation • Enucleation (with a large portion of optic nerve resection) is reserved for nonresponsive, large tumors, usually unilateral presentation as they are more advanced when first seen

Evaluation of Bilateral Optic Disc Edema

• Must rule out elevated ICP‐ requires MRI emergently. • Lumbar puncture once MRI confirms absence of space occupying lesion such as tumor or hemorrhage. DO NOT do LP without MRI first! • May also image orbit looking for local factors unrelated to ICP

Sympathetic Ophthalmia

• Rare, poorly understood bilateral granulomatous response to surgery or trauma in one eye. Note, the trauma or surgery is in one eye, but BOTH eyes become involved with the inflammatory process • Likely autoimmune (T cells primarily) to ocular antigens exposed when first eye insulted • May occur days to over 50 years after inciting event • Only known prevention is to enucleate the injured eye (exciting eye) PRIOR to the onset of inflammation‐may not be practical • Sympathizing eye (non traumatized eye) and Exciting eyes can appear clinically the same with inflammation. • Dalen Fuch's Nodules in mid periphery of retina • Pt. presents with blurred vision, pain, redness, uveitis • Steroids are mainstay of treatment

Lipid Storage Diseases Bilateral Cherry Red Spot

• Tay Sachs/ Sandhoff (GM2 gangliosidoses) • GM1 gangliosidoses • Niemann‐Pick Type A • Sialidosis • Farber Lipogranulomatosis • Others, less common Inborn errors of lipid metabolism. All share in an enzymatic inability to process sphingolipids and gangliosides and lead to deposition in the retina. All are systemic diseases with different manifestations; often death by 3 years old.

CMV Retinitis

• Ubiquitous DNA virus of herpes family, present in over 80% of adults‐present in latent state (CYTOMEGALOVIRUS) • Immunocompetent host it is a limited mono type illness, but in immunocompromised hosts, like AIDS patients, or cancer patients on chemotherapy, it can reactivate and lead to rapid necrotizing retinitis and blindness (brush fire type pattern) • HAART antiviral agents have revolutionized the treatment by allowing immune recovery in AIDS. -Related to low CD4 counts, seen typically if counts are below 50 cells/ul. Seen in AIDS • Multiorgan disease • "Floaters" seen as early stage, rapidly progressing to permanent visual loss if untreated as retina is permanently destroyed • Spreads along retinal vessels • Treatment is intravenous gangciclovir/foscarnet along with HAART in AIDS patients • Intraocular gangciclovir injections can be given in those unable to do intravenous

Central Retinal Artery Occlusion

• Usually embolic blockage of main retinal artery entering eye through Optic N. • CV risk factors, typically 60+ yrs old • Irreversible loss of vision within 90 mins with inner retinal layers ischemic. Severe loss of VA • Swelling of ganglion cell layer‐ opacity • Central fovealis red as no ganglion cell layer present and choroid shows through

Uveal Melanoma (and choroidal)

• Uvea incorporates iris, ciliary body and choroid • Choroidal is most common uveal, 85% • Sporadic onset, possible skin tone - caucasian risk • Arises from melanocytes ‐classic appearance of dome shape lesion from choroid or ciliary body, often mushroom shaped as breaks through Bruch's membrane • Poor prognosis associated with larger size, orange pigment, fluid. • Most often seen incidentally on exam • Flat lesions generally benign nevi CHOROIDAL MELANOMA • Diagnosis based on appearance, ancillary testing such as ultrasound, or biopsy • Treat‐ observation if felt to be benign • Brachytherapy mainstay for conserving eye • Proton beam, thermal, photocoagulation • Enucleation for large, invading optic nerve, etc -METS will kill you

ARMD Treatment

• Vitamin supplementation with increased amounts of zinc, copper and magnesium may slow disease progression (NIH study: AREDS 2) • Healthy diet with dark green leafy vegetables, fish • Exercise, no smoking, limit cardiovascular risk factors • Laser photocoagulation for wet disease to coagulate vessels • Intraocular injections of antivgef medications for regression of wet neovascularization (must be repeated monthly)