Ophthalmology Past Paper - Sclera PDF

OPHTHALMOLOGY P.07A Sclera Dr. Marcello-Tan | August 29, 2024 OUTLINE I. ANATOMY................................................................... 1 A. Sclera.................................................................... 1...

OPHTHALMOLOGY P.07A Sclera Dr. Marcello-Tan | August 29, 2024 OUTLINE I. ANATOMY................................................................... 1 A. Sclera.................................................................... 1 B. Anatomical Considerations.................................... 2 II. HISTOLOGY............................................................... 3 A. Layers of the Sclera............................................. 3 III. FUNCTIONS............................................................... 3 IV. SCLERAL DISEASES.................................................... 4 A. Scleral Discolorations........................................... 4 B. Episcleritis............................................................. 4 Figure 3. Sclera C. Scleritis................................................................. 5 D. Staphyloma........................................................... 5 Ø The sclera is a dense connective tissue made up mainly of: E. Blunt Trauma......................................................... 6 o Type 1 collagen fibers (oriented in different directions) Ø The lack of parallel orientation of the collagen fibers F. Chemical Injury...................................................... 7 o Gives the sclera its white appearance (as opposed to the V. CHECKPOINT............................................................. 8 transparent nature of the cornea) VI. REFERENCES............................................................. 8 o The collagen of the sclera and cornea are continuous. I. ANATOMY A. SCLERA Ø The outer part of the eye Ø Covers the posterior 5/6 of the surface of the globe Ø Continuous with: o Anteriorly: cornea o Posteriorly: posterior scleral foramen – area where the optic nerve passes Figure 4. Lamina cribrosa (red rectangle) Ø Optic disc area: o Outer 2/3 of the sclera: continues with dura mater via the dural sheath of the optic nerve o Inner 1/3 of the sclera: joins with choroidal tissue to form the perforated plate known as lamina cribrosa (where the optic nerve fiber will pass) Figure 1. Right eye (viewed from above) Figure 2. Anatomy of the eye Figure 5. The anatomy of the eye featuring the rectus muscle tendons (stars), Tenon’s capsule (boxed), and the bulbar conjunctiva QUIDASOL, ROSETE, ABRENICA, RAPOSAS OPHTHALMOLOGY Page 1 of 9  OPHTHALMOLOGY P.07A Sclera Dr. Marcello-Tan | August 29, 2024 Ø The sclera is surrounded by the following structures: Ø The sclera is generally avascular, EXCEPT: Insert into superficial scleral o Intrascleral vascular plexus – seen posterior to the Rectus muscle tendons collagen limbus Found anteriorly and covers the o Episcleral vessels – scleral surface Tenon’s capsule sclera and rectus muscle § Superficial plexus: Overlays both the sclera and rectus Radial muscles Beneath Tenon’s capsule E.g., affected in episcleritis Bulbar conjunctiva In the area of the limbus, there is the § Deeper plexus: fusion of the Tenon’s capsule and On the scleral surface bulbar conjunctiva E.g., affected in cases of scleritis B. ANATOMICAL CONSIDERATIONS Ø In studying the sclera, it is important to note the scleral thickness in certain regions Figure 8. Episcleral vessels Figure 6. Diagrammatic representation of the anatomic considerations of the sclera and their measurements. Table 1. Sclera: anatomic considerations Area of the Location Measurement Sclera Posterior insertion of the Thinnest 0.3 mm rectus muscle Posterior pole around Figure 9. Scleral blood vessels Thickest 1.0 mm the optic nerve head Equator 0.4-0.5 mm Emissaria (Apertures) Anterior insertion to the Ø The sclera is penetrated by various arteries and nerves in 0.6 mm many places rectus muscle Ø Such penetrations are called the apertures Ø These are channels that are conduits Ø In strabismus surgery or retinal detachment surgery, there is a need for the careful placement of suture wire → requires Table 2. Emissaria knowing the thickness EMISSARIA VESSELS Features Ø This will guide the surgeon as to the depth of the suture wire Serve as passage of the Located near the in order to prevent inadvertent puncture of choroid and retina anterior ciliary arteries insertions of the going to the anterior recti muscles and ANTERIOR rectus muscle insertions allow entry of the anterior ciliary arteries Serves as the exit point of Affected in vortex veins malignant choroidal MIDDLE melanoma which can have extraocular Figure 7. Vascular portion of the sclera. extension QUIDASOL, ROSETE, ABRENICA, RAPOSAS OPHTHALMOLOGY Page 2 of 9  OPHTHALMOLOGY P.07A Sclera Dr. Marcello-Tan | August 29, 2024 Found in the area of the The sclera is very Ø Inner layer blends with the suprachoroidal lamina cribrosa weak at the level and supraciliary lamellae of the uvea of the lamina LAMINA Ø High density of pigmented cells Ø The collagen fibers branch and intermingle Penetrated by the short cribrosa FUSCA with the outer ciliary in choroid and long posterior Ø This contains a lot of pigment cells and also ciliary vessels and It bulges outward adjacent to the endothelium POSTERIOR nerves in response to ENDOTHELIUM longstanding high intraocular pressure producing optic disc cupping Axenfeld Loops Ø Ciliary nerve branches supplying the cornea Ø Form loops posterior to the nasal and temporal scleral limbus Ø In some eyes, there are some pigmented patches in the nasal and temporal scleral nimbus that may be mistaken Figure 11. The limbus, featuring the episcleral and sclera. for uveal tissues or malignant melanoma Figure 10. Axenfeld’s loop. II. HISTOLOGY A. LAYERS OF THE SCLERA Figure 12. Histological layers of the sclera (from outer to inner: episcleral, stroma, lamina fusca, and endothelium. Table 3. Layers of the Sclera Layers Description III. FUNCTIONS Ø Outermost part Ø Maintains the shape of the globe Ø Dense vascular connective tissue Ø Resists internal and external forces Ø Anterior to the rectus muscle that merges: Ø Provides attachment for the extraocular muscles o Posteriorly: superficial scleral stroma o Anteriorly: fuses with the Tenon’s capsule and the conjunctiva EPISCLERA Ø Blood supply: o Anterior ciliary arteries § Deep in the conjunctiva § Plexus between the muscle insertions and limbus Ø Inflammation: appear as red and congested (episcleritis) Ø Made up of bundles of collagen + fibroblasts + proteoglycans + glycoproteins SCLERAL Ø Opaque, porcelain-white appearance STROMA o Can be attributed to the greater variation (SUBSTANCIA in the collagen type 1 fibril PROPRIA) arrangement Figure 13. Eye model featuring the sclera to aid visualization of its o Can be due to greater fibril interweaving functions. in mucopolysaccharide, resulting in an irregular arrangement QUIDASOL, ROSETE, ABRENICA, RAPOSAS OPHTHALMOLOGY Page 3 of 9  OPHTHALMOLOGY P.07A Sclera Dr. Marcello-Tan | August 29, 2024 IV. SCLERAL DISEASES A. SCLERAL DISCOLORATIONS 1. Scleral Melanocytosis Ø Congenital benign melanocytic hyperpigmentation of the sclera which presents with small black or gray-blue spots Ø This is caused by an increase in the melanocytes in the iris, choroid and surrounding structure Ø May occur by itself or associated with other oculodermal melanocytosis or Nevus of Ota Figure 15. Slate-grey hyperpigmentation in the areas of distribution of ophthalmic and maxillary branches of the trigeminal nerve as well as nasal mucosa (a) and hyperpigmentation in the sclera (b) 3. Jaundice Ø The skin, sclera, and mucous membranes turn yellow Ø Caused by high levels of bilirubin which is a yellow-orange bile pigment secreted by the liver, formed from the breakdown of red blood cells Ø Infantile jaundice: o Common condition in preterm babies before 38 weeks AOG and in some breastfed infants o This usually occurs because the baby’s liver is not yet mature enough and unable to get rid of the bilirubin in the bloodstream Figure 14. Nevus of Ota exhibiting scleral melanocytosis o Usually, this manifests in the 2nd to 4th day of birth, and this is still considered physiologic jaundice, thus no 2. Oculodermal Melanocytosis (Nevus of Ota) treatment is warranted Ø Characterized by scleral melanocytosis o In some babies, underlying disease may cause infantile Ø Melanocytic hyperpigmentation of the skin – in the areas jaundice such as: supplied by the ophthalmic and maxillary divisions of the § Birth trauma trigeminal nerve § Mother-baby blood type incompatibility o The color of the affected skin varies from light § Low caloric intake or dehydration due to difficulty brown to dark nursing or not getting enough nutrition from Ø Typically presents at birth to puberty, but can also appear breastfeeding during puberty or during pregnancy § Race: East Asian are prone to having infantile jaundice Ø F > M (more commonly seen in females with 5:1 ratio) Ø Importance of monitoring infant patient with jaundice: Ø Common in Asian > African > White o Complication: kernicterus – high bilirubin can cause o If seen in Caucasians, this accords a higher risk brain damage in developing malignant melanoma Ø Prevention: adequate feeding preferably breastfeeding Ø Histopathology: melanocytes o When the mother is breastfeeding or using formula Ø Histopathologically: in the nevus of Ota, there is excessive frequent feeding and in hospital, they do phototherapy dendritic melanocytes in the affected tissues (help the liver breakdown bilirubin) o Because of this increase in melanocytic cells, one of the complications will be glaucoma especially if there is an increase in the melanocytic cells along the trabecular meshwork Ø What is the function of the trabecular meshwork? o Drainage of the aqueous o In the area of the limbus, if the pigmentary cells hypertrophy or undergo hyperplastic changes, this leads to increase of melanocytic cells → clogging of the Figure 16. Jaundice trabecular meshwork → no drainage of aqueous fluid → increased IOP (glaucoma) → damage to the optic nerve Ø Complications: o Glaucoma o Malignant cutaneous melanoma o Ocular melanoma Ø Management: o Yearly screening by an ophthalmologist and dermatologist is recommended o Surgical resection is not advisable Figure 17. Infantile jaundice: note the yellow discoloration of the sclera. QUIDASOL, ROSETE, ABRENICA, RAPOSAS OPHTHALMOLOGY Page 4 of 9  OPHTHALMOLOGY P.07A Sclera Dr. Marcello-Tan | August 29, 2024 B. EPISCLERITIS C. SCLERITIS Ø Common benign, self-limited inflammation of the episcleral Ø Serious inflammation of the sclera tissue Ø Associated with autoimmune diseases like rheumatoid Ø Etiology: arthritis, and the first symptom of connective tissue disease o Idiopathic Ø Classification: o 26-36% systemic disorder (e.g., collagen vascular Anterior Posterior disease (rheumatoid arthritis), dermatologic, metabolic, Ø More common (98% of Ø Rare, usually present atopy) cases) with pain and o Malignancy Ø 2 types: tenderness o Foreign body Non- Ø Serious complications o Chemical injury Necrotizing necrotizing (e.g., retinal o Infectious (e.g. viral, bacterial, protozoal) Ø More Ø Less detachment and angle- Ø Usually seen in 20-50 y/o common common closure glaucoma) Ø More common in females than males (F > M) Ø (Diffuse vs (around Ø Present as an acute or gradual onset of eye redness nodular) 13% of Ø Usually unilateral cases) Ø Most of the time the patient is asymptomatic and complains of eye redness, (+/-) pain, discomfort, photophobia, tenderness (a) (b) Figure 20. Non-necrotizing (a) vs. necrotizing (b) scleritis. Table 5. Scleritis Ø Autoimmune disease (e.g., lupus, arthritis, IBD, Sjogren’s, scleroderma) Figure 18. Episcleritis, showing superficial temporal redness of the left eye. Episcleritis is not serious and is usually self-limiting, requiring only Etiology Ø Idiopathic symptomatic treatment with topical lubricants. Ø Trauma to the eye Ø Rarely, infection (fungus, parasite) Ø Pain and tenderness: severe ocular pain radiating to the jaw (pain is described as boring) Ø Redness of sclera and conjunctiva Symptoms Ø Blurred vision: associated visual acuity decline and may lead to blindness (a) (b) Figure 19. Simple (a) and nodular (b) types of episcleritis Ø Tearing Ø Light sensitivity: photophobia Table 4. Simple vs. Nodular episcleritis + episcleritis in general and its Ø Clinical and slit lamp exam: examining the diagnosis and management sclera in daylight, retracting the lids to help Simple/Diffuse Episcleritis Nodular Episcleritis determine the extent of the involvement Ø Other aspects of eye examination (visual acuity and slit exam) may be normal Diagnosis Ø Phenylephrine test: To differentiate scleritis from episcleritis (causes the blanching of the blood vessels in episcleritis but not in scleritis) Ø Ancillary tests: CT scan, MRI, UTZ (does not replace the importance of physical examination) Vascular congestion without Redness with discrete, Ø NSAIDs – relieve pain and inflammation (e.g., nodule elevated area of episcleral ASA, IBU) tissue Ø Corticosteroids – steroid eyedrops to tone down the inflammatory process o 2.5% phenylephrine drops is used to Ø Immunosuppressives/immunomodulators differentiate episcleritis from scleritis – for more severe scleritis o Episcleritis with 2.5% phenylephrine drops: Diagnosis Treatment Ø Antibiotics or antivirals for etiologic cause there will be blanching of the redness Ø Surgery: indicated if scleral perforation and o Systemic workup, especially if recurrent or severe scleral thinning are present present of underlying systemic infection Ø The bandage contact lens can be used or o First episodes: cool compresses Management corneal glue to repair damaged corneal o Oral NSAIDs tissue in the eye QUIDASOL, ROSETE, ABRENICA, RAPOSAS OPHTHALMOLOGY Page 5 of 9  OPHTHALMOLOGY P.07A Sclera Dr. Marcello-Tan | August 29, 2024 Ø Scleral patch graft: o Equator of the eye, region circumferencing the largest diameter of the eye o More posterior, related to scleritis and pathologic myopia o Patients with nearsightedness can have equatorial staphylomas well as posterior staphyloma EQUATORIAL Ø Scleritis is a serious condition; if not treated, will lead to blindness D. STAPHYLOMA Ø Abnormal protrusion of uveal tissue through a weakened point in the eyeball Ø Generally black in color Ø Black color is due to the inner layers of the eye, specifically o Can be seen around the optic nerve and the the choroid macular area Ø Occurs due to weakening of the outer layers of the eye and o A majority is developed as a result of etiology may also be autoimmune, inflammatory, and pathologic myopia degenerative conditions o This can also result from congenital, Ø Term used for ectatic sclera, which has become attached to infectious, and inflammatory disorders the underlying uvea (ectatic means dilated or distended) o Expansion of the posterior fundus including Ø May occur following severe scleritis or uveitis the macula and optic nerve POSTERIOR Table 6. Types of staphyloma o It involves the weakening of the cornea and nearby sclera ANTERIOR o It is seen as a localized bulge in the limbal area o Area of the root of the iris and the ciliary body INTERCALARY Figure 21. Types of staphyloma (right) in contrast to the normal appearance of the uvea (left) E. BLUNT TRAUMA o Bulge of the weak sclera is lined by the ciliary Ø Common sites of scleral rupture: body, which occurs 2-3 mm away from the o Superonasal quadrant, near the limbus limbus o Circumferential arc parallel to the corneal limbus which o More posterior, around 2-3 mm from the radius is opposite to the site of impact o Behind the insertion of the rectus muscles (thinnest area), which is also the common site of rupture § It is the thinnest part of the sclera – 0.3 mm = common site of scleral rupture CILIARY § Why not anterior? – 0.6 mm in the anterior rectus muscle insertion Ø Symptoms: o Pain and decreased vision o Full-thickness scleral laceration o Subconjunctival hemorrhage o Limitation of extraocular muscle movement QUIDASOL, ROSETE, ABRENICA, RAPOSAS OPHTHALMOLOGY Page 6 of 9  OPHTHALMOLOGY P.07A Sclera Dr. Marcello-Tan | August 29, 2024 o Extrusion of the content of the eye (e.g., uveal extrusion) Ø Diagnostics include: o Orbital CT scan (axial and coronal views) of the orbits and brain o B-Scan Ultrasonography To localize the rupture site and rule out intraocular foreign body, especially if trauma is related to other injuries o Protect the eye with a shield o Admit and put on NPO, on bedrest o Start the patient with topical and systemic antibiotics o +/- tetanus toxoid MANAGEMENT Figure 22. Sites of scleral rupture in cases of blunt trauma on the eye. o Schedule for repair o Protect the other eye o Highly dependent on the severity of ocular PROGNOSIS damage F. CHEMICAL INJURY Ø The sclera is highly resistant to injury from brief exposure to toxic chemicals because of the excessive production of Figure 23. Blunt trauma consequences: pain and decreased vision. tears Table 9. Chemical injury: Acids vs. Alkali Table 8. Blunt trauma in the ER Acids Alkali What to do? Steps Ø pH below 2.5: source of Ø pH above 11.5 greatest acidic burn Ø Sulfuric acid (e.g., car Ø Ammonium hydroxide or batteries) ammonium chloride (or other chemicals with pH >11.5) Ø Common household agents such as household INITIAL o Check visual acuity: defer other cleaners, fertilizers, oven CONTACT procedures that apply undue pressure to cleaners, cement, and lye prevent blurring and possible extrusion of Ø Seldom results in the loss Ø More serious because they intraocular contents of the eye will cause liquefaction o Most often than not, they will have reduced visual acuity Ø Tend to have better necrosis and can o Use a protective eye shield to prevent prognosis/outcome penetrate deeper further injuries or accidents Ø Precipitates proteins Ø Liquefactive necrosis o Use penlight or slit lamp, if available (be Ø MEDICAL EMERGENCY very gentle) REQUIRING IMMEDIATE o Refer immediately TREATMENT Between acid and alkali, alkali burns are the worst QUIDASOL, ROSETE, ABRENICA, RAPOSAS OPHTHALMOLOGY Page 7 of 9  OPHTHALMOLOGY P.07A Sclera Dr. Marcello-Tan | August 29, 2024 Table 10. Emergency treatment 4. Inner 1/3 of the sclera and choroidal tissue form a Emergency Treatment perforated plate called ________________ Ø Determine first the chemical or offending agent (either an 5. Sclera is generally avascular, except ______________ alkali or an acid) and _____________ Ø Copious irrigation with saline or LRS or clean water for at 6. __________ epissaria is affected in malignant choroidal least 30 minutes o DO NOT USE ACIDIC SOLUTIONS TO NEUTRALIZE melanoma ALKALI and VICE VERSA 7. Layer of the sclera that has the highest density of Ø Place topical anesthetics – for the patient to be more pigmented cells comfortable while doing irrigation 8. Diagnostic test done to differentiate scleritis and Ø After 5-10 minutes, check the pH level using litmus paper episcleritis touched to the inferior cul-de-sac if neutralized (pH 7.0) Ø Make sure that the inferior and superior fornices are PROBLEM SOLVING: irrigated o The upper eyelid should be everted Case: A patient came it due to slate grey hyperpigmentation Ø Sweep conjunctival fornixes around her right eye extending from her right forehead to her Ø Refer to an ophthalmologist: the ophthalmologist can give right cheeks. topical antibiotics, cycloplegic, pain relief, anti-glaucoma 9. What is the most likely diagnosis? meds, and topical steroids 10. Common complications associated with #9 11. T/F: The best management would be surgical resection Table 11. Complications. Common Complications Case: A baby was brought to your clinic due to yellowish Ø Eye pain discoloration of her skin, sclera, and mucous membrane. Ø Ischemia Ø Corneal edema or opacification 12. This is due to high levels of? Ø Increased IOP: possible glaucoma 13. Complication associated with the above case Ø Corneal neovascularization may affect corneal clarity Ø Symblepharon: adhesion between eyelid and cornea MATCHING TYPE: Ø Blindness A. Simple Episcleritis B. Nodular Episcleritis C. Both 14. Vacular congestion 15. Managed with cold compress 16. Pain management includes oral NSAIDs 17. With discrete elevated area of episcleral tissue A. Intercalary B. Ciliary C. Equatorial D. Posterior E. Anterior 18. Related to scleritis and pathologic myopia Figure 24. Scleral chemical injury 19. Localized bulging in the limbal area 20. Weakening of the cornea and nearby sclera o Stained cornea – use fluorescein dye to check if there E 20. is erosion of the epithelium (upper left) A 19. C 18. o Opaque cornea – no longer clear, edema of the cornea B 17. (upper right) C 16. C 15. o Limbal ischemia – no blood flow (lower left) A 14. o Corneal neovascularization – vessels on top of the Kernicterus 13. Bilirubin 12. cornea from sclera, there is a tag of skin (lower right) False; not advisable 11. Glucoma, malignant cutaneous melanoma, ocular melanoma 10. Oculodermal melanocytosis 9. V. CHECKPOINT! 2.5% phenylephrine test Lamina fusca 8. 7. IDENTIFICATION: Middle 6. Intrascleral vascular plexus, episcleral vessels 5. 1. Outer part of the eye Lamina cribrosa 4. 2. Sclera is connected anteriorly with ___________, and Type 1 collage fiber 3. Cornea, posterior scleral foramen 2. __________________ posteriorly Sclera 1. 3. Sclera’s dense connective tissue is made up of ________________ QUIDASOL, ROSETE, ABRENICA, RAPOSAS OPHTHALMOLOGY Page 8 of 9  OPHTHALMOLOGY P.07A Sclera Dr. Marcello-Tan | August 29, 2024 VI. REFERENCES Ø Ophthalmology trans of 2025 Ø Dr. Marcello-Tan’s Lecture Ø Ajamian, P. (2020, April 15). In the Red Zone. Review of Optometry. https://www.reviewofoptometry.com/article/in-the-red-zone Ø De Sarker BK, Malek MIA, Abdullahi SM, Iftekhar S, Sakeb N, Mahatma M, et al. Ophthalmic associations of oculodermal melanocytosis in a tertiary eye hospital in South Asia. Therapeutic Advances in Ophthalmology [Internet]. 2021 Jan 1;13:251584142199353. Available from: https://doi.org/10.1177/2515841421993539 Ø Majumder, P. D. (2020, April 5). Anatomy of sclera. eOphtha. https://www.eophtha.com/posts/anatomy-of-sclera Ø Morarji, Jiten & Lightman, Sue & Taylor, Simon. (2011). The eye in rheumatology. British journal of hospital medicine (London, England: 2005). 72. 682-5. 10.12968/hmed.2011.72.12.682. QUIDASOL, ROSETE, ABRENICA, RAPOSAS OPHTHALMOLOGY Page 9 of 9  OPHTHALMOLOGY P.07B Vitreous Dr. Marcelo-Tan | August 29, 2024 OUTLINE o VITREOUS BASE: dense collagen fibers § Ringlike area extending 2 mm anterior and 3-4 I. VITREOUS HUMOR...................................................... 1 mm posterior to the ora serrata A. Introduction........................................................... 1 § Junction between the ciliary body and the choroid B. The 2 Topographic Areas......................................... 1 of the retina II. DEVELOPMENT........................................................... 1 Annular gap/canal of Petit: diffusion A. Primary Vitreous.................................................... 1 between aqueous and vitreous B. Secondary Vitreous................................................ 1 compartments C. Tertiary Vitreous..................................................... 2 D. Vitreous Body Changes.......................................... 2 III. BIOCHEMICAL PROPERTIES....................................... 2 IV. CLINICAL CONSIDERATIONS AND PATHOLOGIES....... 2 A. Function of the Vitreous......................................... 2 B. Persistent Fetal Vasculature................................... 2 C. Vitreous Detachment............................................. 2 D. Vitreous Opacities.................................................. 3 E. Vitreous Incarceration............................................ 3 F. Vitritis.................................................................... 4 G. Acute Postoperative Endophthalmitis..................... 4 V. Checkpoint................................................................ 4 VI. References................................................................ 5 I. VITREOUS HUMOR A. INTRODUCTION Figure 2. Vitreous: take note of the parts in the cortical vitreous mentioned. Ø Latin “vitrum”: glass-like Ø 80% of the volume of the eye, roughly around 4 mL Ø Transparent gel that fills the vitreous cavity that contains: II. DEVELOPMENT o Water A. PRIMARY VITREOUS o Collagen fibrils (vitreous/hyaloid membrane) Ø Develops by the end of the 3rd embryonic week o Hyaluronan – acts as fillers between collagen fibrils o Contains primary hyaloid vessels which supply nutrients to the lens B. THE 2 TOPOGRAPHIC AREAS Ø Hyaloid vessels disappear before birth Ø Cloquet’s canal/hyaloid canal o Area of Martegiani: condensation of tissues found around the optic nerve o Vitreous inserts on the edges of the optic nerve head, creating a funnel-shaped void Figure 1. Topographical areas of the vitreous humor Figure 3. Primary Vitreous Ø Core vitreous: central part of the vitreous cavity B. SECONDARY VITREOUS Ø Cortical vitreous: peripheral part of the vitreous cavity Ø Develops by the 9th week o ANTERIOR CORTICAL GEL: anterior surface of the Ø Becomes the mature vitreous vitreous body Ø Fills the globe and compacts the primary vitreous § LIGAMENT OF WIEGER: condensation of collagen fibers attached to the posterior lens capsule § PATELLAR FOSSA: indentation created by the posterior surface of the lens to the anterior surface of the anterior cortical gel § BERGER SPACE: potential space between peripheral posterior lens and anterior cortical gel Figure 4. Secondary Vitreous EMPERADOR, ROSETE, ABRENICA, RAPOSAS OPHTHALMOLOGY Page 1 of 5  OPHTHALMOLOGY P.07B Vitreous Dr. Marcelo-Tan | August 29, 2024 C. TERTIARY VITREOUS III. BIOCHEMICAL PROPERTIES Ø Develops by 6th month embryonic age Ø Similar to cornea, except there are very few cells: Ø Fibrous structure of secondary vitreous condenses and o Phagocytes: remove unwanted cellular debris in the forms the lens zonules (suspensory structures that visual field suspends the lens to the eyeball) o Hyalocytes: which turnover the hyaluronan Ø 98-99%: Water o As opposed to the cornea (75% only) Ø 1%: collagen type Il, glycosaminoglycans, hyaluronan, salts, vitrosin Ø No blood vessels Ø High ascorbate levels Ø Gelatinous consistency: 2-4x more viscous than water Ø Refractive index: 1.336 and devoid of blood vessels Figure 5. Tertiary Vitreous IV. CLINICAL CONSIDERATIONS AND PATHOLOGIES A. FUNCTION OF THE VITREOUS D. VITREOUS BODY CHANGES Ø Storage area for metabolites Ø Produced by cells in the non-pigmented ciliary body (from embryonic mesenchymal cells) o Intravitreal injection of medications Ø Shock absorber for trauma Ø Changes in nature and composition: Ø Light transmission o At birth: no vitreous fluid, only gel-like o 4-5 years old: with vitreous fluid Note by Doc: Five strong attachments of the vitreous: o Adolescence: vitreous cortex becomes more dense 1. Vitreous base o Adulthood: core vitreous liquefies, fibrillar 2. Posterior lens capsule degeneration, syneresis course strands develops, 3. Area around optic nerve gel volume decreases, liquid increases 4. Macula 5. Retinal vessels B. PERSISTENT FETAL VASCULATURE Ø Persistent embryonic tissue which usually regresses during gestation (28-30 weeks AOG) o Unilateral usually o Leukocoria or white pupil o Reduced VA to blindness o Microphthalmia Figure 7. Persistent fetal vasculature: Remnants of the hyaloid artery Figure 6. Age-related vitreous liquefaction and posterior vitreous detachment (PVD) Table 1. Anterior vs posterior persistent fetal vasculature Anterior PFV Posterior PFV Pockets of liquid appear within the central vitreous that gradually coalesce Slit lamp examination: Slit lamp examination: ↓ Ø Lens changes Ø Possible retinal There is a concurrent weakening of post-oral vitreoretinal (membranous detachment and adhesion cataract) retinal dysplasia ↓ Ø Vascularized whitish Ocular ultrasound: if it can't Eventually, this can progress to PVD, where the liquid retrolental tissue be viewed under fundus exam, vitreous dissects the residual cortical gel away from the ILL Ø Ciliary body villi IRREVERSIBLE on the inner surface of the retina as far anteriorly as the visible in the pupil posterior border of the vitreous base Note by Doc: normal process, not pathologic EMPERADOR, ROSETE, ABRENICA, RAPOSAS OPHTHALMOLOGY Page 2 of 5  OPHTHALMOLOGY P.07B Vitreous Dr. Marcelo-Tan | August 29, 2024 Ø Treatment: symptomatic (only intervene if there are PIGMENT GRANULES symptoms) Ø Tobacco dust/Shafer's sign Ø Complications: glaucoma (due to drainage disorders), Ø Pigment cells in the anterior vitreous retinal detachment, vitreous hemorrhage Ø Seen in presence of retinal breaks C. VITREOUS DETACHMENT Ø 2 things happen: o Synthesis: increase in gel o Syneresis: increase breakdown of collagen arrangement Ø Causes of syneresis: o Aging o Nearsightedness o Uveitis o Post-injury o Surgery Ø Floaters: spots or transparent shapes in the visual field Figure 9. Tobacco dust / Shafer’s sign observed in the image Ø Diagnosis: o Clinical Question by doc: where did the pigment granules come o Slit lamp: Weiss ring (fibroglial tissue) from? o B-scan ultrasound: thin hyperreflective line within the vitreous cavity Answer: released from the iris or retinal pigment epithelium D. VITREOUS OPACITIES VITREOUS HEMORRHAGE ASTEROID HYALOSIS Ø Causes: Ø Minute white opacities of calcium-containing o Diabetic retinopathy phospholipids o Retinal breaks without detachment Ø Etiology is unknown o Peripheral vascular disease o But correlation to diabetes mellitus → o Rhegmatogenous retinal detachment hypercholesterolemia o Retinal neovascularization (e.g., central retinal vein Ø Features: occlusion (CRVO), branch retinal vein occlusion o >50-year-old, and usually unilateral (BRVO)) o Usually asymptomatic o Trauma o Floaters Ø Diagnostics: o Rare decrease in visual acuity o Dilated ophthalmoscopy Ø Diagnosis: slit lamp exam; fluorescein angiogram o Ocular ultrasound Ø Treatment: observe, pars plana vitrectomy (PPV) Ø Management: o High back rest o Pars plana vitrectomy (PPV) if too thick (not resolving in 6 months) Figure 8. Asteroid hyalosis: white opacities observed when performing slit lamp examination. CHOLESTEROLOSIS Figure 10. Normal retina (left) vs Hemorrhage occurring in the vitreous humor obscuring retinal details. Ø Also known as: SYNCHYSIS SCINTILLANS Ø Numerous highly refractile yellow-white, gold, or E. VITREOUS INCARCERATION multicolored cholesterol crystals Ø During complicated cataract or vitreous surgery Ø Association: repeated or severe accidental or surgical Ø Complications: trauma with large intravitreal hemorrhages o Endophthalmitis Ø Crystals settle inferiorly due to PVD o Hypotony and collapse of anterior chamber Ø Features: o Asymptomatic o Secondary glaucoma o Floaters o Retinal detachment Ø Diagnostics: slit lamp – snow-globe effect Ø Treatment: not indicated EMPERADOR, ROSETE, ABRENICA, RAPOSAS OPHTHALMOLOGY Page 3 of 5  OPHTHALMOLOGY P.07B Vitreous Dr. Marcelo-Tan | August 29, 2024 Ø Treatment: Ø Etiology: 1. Intraocular inflammation (e.g., intermediate uveitis): o Changes in vitreous: ▪ Liquefaction ▪ Shrinkage ▪ Vitreous gel will contract ▪ The eyeball will be filled with aqueous humor o Opacification ▪ Affects vision: floaters and blurring ▪ Ex: toxoplasmosis and pars planitis o TREATMENT: RULE OUT INFECTION PRIOR TO CORTICOSTEROID AND IMMUNOSUPPRESSION 2. Infectious: o Endophthalmitis ▪ Purulent inflammation of the intraocular fluids ▪ Hallmark: progressive vitritis ▪ Histology: inflammatory cells ▪ Causes: - Endogenous: bacterial, fungal - Exogenous: postoperative, traumatic, filtering bleb associated, after intravitreal injections, corneal ulcers Figure 11. Treatment of vitreous incarceration (A) Narrow vitreous strand to a cataract wound. The inset Figure 13. Progression of endophthalmitis shows possible laser pathways for vitreolysis: Left: early stages, Right: late stages. 1. A gonioscopic approach, directed at the cataract wound—the location at which the vitreous strand is 3. Autoimmune often the most discrete 4. Ocular tumors (e.g., primary intraocular lymphoma) 2. A direct approach near the limbus 3. A direct approach in the region of the collarette; and G. ACUTE POSTOPERATIVE ENDOPHTHALMITIS 4. A direct approach at the pupil Ø Occurs 3-5 days or 1-2 weeks after surgery o This last approach is rarely successful Ø Incidence after cataract surgery: 0.08% to 0.68% (B) A broad vitreous band at the wound Ø Symptoms: (C) Iris pulled upward in a tent like configuration and o Pain, eye redness, discharge, and decreased visual entrapped by the vitreous incarceration in the wound acuity o Lid swelling, conjunctival, and corneal edema Ø Signs: retinal periphlebitis Ø Endophthalmitis vitrectomy study o Most common symptom: blurred visual acuity o Most common sign: hypopyon Ø Visual acuity determination is most important: o Visual acuity = light perception or worse: pars plana vitrectomy (PPV) o Visual acuity = hand motions or better: tap and inject intravitreal antibiotics Figure 12. Vitreous wick syndrome, peaked pupil appearance seen in vitreous incarceration F. VITRITIS Ø Cellular infiltration Ø Symptoms: o Blurring of vision o Eye redness o Pain Figure 14. Postoperative endophthalmitis: most common sign is o Photosensitivity hypopyon, which occurs when exudates accumulate/ collect in the anterior chamber of the eye. EMPERADOR, ROSETE, ABRENICA, RAPOSAS OPHTHALMOLOGY Page 4 of 5  OPHTHALMOLOGY P.07B Vitreous Dr. Marcelo-Tan | August 29, 2024 Ø Diagnostics: A. Cholesterolosis 1. Microbiological studies: B: Pigment Granules o Bacteria from own periocular flora, oral flora C. Vitreous Hemorrhage o Vitreous sampling D. Vitreous Incarceration o Endophthalmitis vitrectomy study (EVS): ▪ 94.2% of culture confirmed cases gram-positive 8. Common during complicated cataract or vitreous bacteria surgery ▪ 70%: gram-positive coagulase-negative 9. Synchysus Scintillans staphylococci 10. Tobacco sign/ Shafer’s sign - Staphylococcus epidermidis 2. Ocular ultrasound: B 10. o Vitreous opacities with vitritis A 9. o Thickened choroid D 8. B 7. A 6. B 5. A 4. Area of Martegiani 3. Vitreous Base 2. Vitreous Humor 1. VI. REFERENCES Ø Dr. Marcelo-Tan’s lecture Figure 15. Ocular ultrasound vitreous opacities with vitritis and a thickened choroid. Ø Treatment: o Intravitreal antibiotics: § Vancomycin 1.0 mg/0.1 ml § Ceftazidime 2.25 mg/0.01 ml § Amphotericin B or voriconazole o Pars plana vitrectomy § To reduce bacterial load § Disadvantage: need for sophisticated equipment o Systemic antibiotics: 4th generation fluoroquinolones (e.g., ciprofloxacin, gatifloxacin, moxifloxacin, and ceftazidime) o Corticosteroids: § Minimize ocular damage from the inflammatory response § Not given for fungal etiologies V. CHECKPOINT! IDENTIFICATION: 1. 80% of the volume of the eye 2. Ringlike area extending 2mm anterior and 3-4mm posterior to the ora serrata 3. Condensation of the tissue found around the optic nerve MATCHING TYPE: A. Anterior PFV B. Posterior PFV 4. Vascularized whitish retrolental tissue 5. Irreversible 6. Ciliary body villi visible in the pupil 7. Possible retinal detachment EMPERADOR, ROSETE, ABRENICA, RAPOSAS OPHTHALMOLOGY Page 5 of 5  OPHTHALMOLOGY P.08 Uvea Dr. Chiu-Ang | September 5, 2024 OUTLINE B. EMBRYOLOGY I. UVEA.......................................................................... 1 Table 1. Embryology of the Uvea A. Anatomy and Physiology........................................ 1 Iris Ciliary Body Choroid B. Embryology........................................................... 1 C. Vascular Supply.................................................... 1 II. PARTS OF THE UVEA.................................................... 1 A. Iris........................................................................ 1 B. Ciliary Body........................................................... 2 C. Choroid................................................................ 2 Fig. 3. Anatomy of the Fig. 2. The iris ciliary process III. UVEITIS....................................................................... 2 Fig. 4. The choroid A. SUN Classification................................................ 3 B. Terminology.......................................................... 3 Epithelium: Epithelium: Mainly derived C. Systemic Workup.................................................. 4 neuroectodermal neuroectodermal from the inner D. Ocular Diagnostics................................................ 4 vascular layer of Sphincter & Stroma, ciliary mesenchyme that IV.CLASSIFICATIONS OF UVEITIS..................................... 4 muscles, & blood surrounds the A. Anterior Uveitis..................................................... 4 dilator pupillae: vessels: optic cup B. Intermediate Uveitis.............................................. 6 neuroectodermal mesenchyme C. Posterior Uveitis.................................................... 6 Melanocytes: D. Panuveitis........................................................... 10 Stroma & blood originate from the E. Uveitis with High Intraocular Pressure (IOP) & Iris vessels: neural crest Atrophy............................................................... 10 Mesenchyme V. Checkpoint.............................................................. 10 VI. References.............................................................. 11 C. VASCULAR SUPPLY AND VENOUS DRAINAGE Pre-lecture Questions Ø Vascular supply: 1. What are the parts of the uvea? o Short posterior ciliary arteries Iris, ciliary body, choroid o Long posterior ciliary arteries 2. What is the function of the iris? o Anterior ciliary arteries Controls the amount of light that comes in the eye Ø Venous drainage: 3. What is uveitis? o Vortex veins Inflammation of the uvea 4. What are the classifications of uveitis based on anatomy? Anterior uveitis, intermediate uveitis, posterior uveitis, panuveitis I. UVEA A. ANATOMY AND PHYSIOLOGY Ø UVEA o Pigmented, vascular, middle layer of the eye Ø FUNCTIONS o Regulates light entry o Absorbs reflected light o Nourishes eye Ø 3 PARTS o Iris Figure 5. Vascular Supply and Venous Drainage of the Uvea o Ciliary body o Choroid II. PARTS OF THE UVEA A. IRIS Anatomy and Physiology Ø Anterior most part that surrounds the pupil and metabolizes the anterior segment Ø Average diameter: 12 mm Ø Thickness: 0.5 mm Ø In the center, an aperture of 3-4 mm = PUPIL Ø Thinnest at its root, wherein it is the area that tears away easily on blunt trauma (IRIDODIALYSIS) Ø Divides space into anterior and posterior chambers (Fig. Figure 1. Parts of the uvea 6) CERVA, DAGUITAN, DELA CRUZ, EMPERADOR, QUIDASOL, ROSETE, ABRENICA, RAPOSAS OPHTHALMOLOGY Page 1 of 15  OPHTHALMOLOGY P.08 Uvea Dr. Chiu-Ang | September 5, 2024 Ø Anteriorly, the iris is divided into two parts by collarette (thickest part of the iris 0.6-1 mm wide located 2 mm from the pupillary margin) o Inner pupillary zone (1-2 mm wide) o Outer ciliary zone (3-4 mm wide) Figure 8. The ciliary body triangle Figure 6. The iris and its location in a schematic diagram Ø Sphincter pupillae muscle: o Constricts the pupil o Forms 1 mm broad circular band in the pupillary zone of the iris o Parasympathetic fibers (3rd nerve) Ø Dilator pupillae muscle: o Dilates the pupil o Lies in the stroma of the ciliary zone o Cervical sympathetic nerves Figure 9. Parts of the ciliary body When do the pupils constrict/dilate? Bright light = constrict C. CHOROID Dark = dilate Ø Nourishes the outer layers of the retina Ø Posterior-most part of the uvea Ø Extends from optic disc to ora serrata Ø Inner surface: smooth and brown (RPE) Ø Outer surface: rough (sclera) Figure 7. Iris structure: sagittal plane B. CILIARY BODY Ø Produces aqueous humor, the fluid that fills the front of the eye Ø Cut section: triangular shape Figure 10. Choroid the surrounding structures o Anterior side (A) – form part of the angle of the anterior and posterior segment III. UVEITIS o Middle – iris is attached Ø The classification of uveitis, established by the SUN o Outer side (O) – lies against the sclera (Standardization of Uveitis Nomenclature) Working Ø 2 parts of the ciliary body (I): Group, is based on the primary site of inflammation: o Pars plicata – ciliary processes (serrated area) o Anterior uveitis (red) involves the iris and anterior § 2-2.5 mm ciliary body o Pars plana – smooth/flat o Intermediate uveitis (blue) involves the posterior § 5 mm wide temporally, 3 mm nasally ciliary body and the pars plana, and/or the peripheral § Allows access to the posterior segment to treat retina many vitreoretinal diseases o Posterior uveitis (green) involves the choroid, either § Pars plana vitrectomy: access to the posterior primarily or secondarily from the retina segment to treat many vitreoretinal diseases CERVA, DAGUITAN, DELA CRUZ, EMPERADOR, QUIDASOL, ROSETE, ABRENICA, RAPOSAS OPHTHALMOLOGY Page 2 of 15  OPHTHALMOLOGY P.08 Uvea Dr. Chiu-Ang | September 5, 2024 Table 3. The SUN Working Group Descriptors of Uveitis Figure 11. Anterior, intermediate, and posterior part of choroid A. SUN CLASSIFICATION *Study and memorize all SUN Classification criteria (Tables 2-5) *Remember the duration Table 2. The SUN Working Group Anatomic Classification of Uveitis Table 4. The SUN Working Group Activity of Uveitis Terminology (Larger at end of trans) Table 5. SUN grading system for Grading, anterior chamber (AC) cell, and flare severity. The presence or absence of a hypopyon should be noted separately in addition to the AC cellular activity grade. Cells: Active Inflammation Flare: Leakage of Protein (can be active or not) AC Cells Grade AC Flare (1 mm x 1 mm slit beam) 0 50 Intense (fibrin or plasmoid aqueous) Ø Anterior uveitis: B. TERMINOLOGY o Idiopathic is the most common type Table 6. Terminologies in uveitis Ø Intermediate uveitis: o Pars planitis is the most common intermediate Granulomatous: composed of lymphocytes, plasma cells, uveitis and giant cells Ø Posterior uveitis: o Neuroretinitis includes the optic disc Ø Panuveitis affects all anatomical areas (anterior down to Mutton-fat Keratic posterior) Precipitates o Most of the posterior uveitis are panuveitis (matataba siya compared sa (diseases overlap) non-granulomatous) CERVA, DAGUITAN, DELA CRUZ, EMPERADOR, QUIDASOL, ROSETE, ABRENICA, RAPOSAS OPHTHALMOLOGY Page 3 of 15  OPHTHALMOLOGY P.08 Uvea Dr. Chiu-Ang | September 5, 2024 Koeppe’s nodules (pupillary C. SYSTEMIC WORKUP margin) Table 7. Investigations in the Standardized Strategy for the Etiologic Diagnosis of Uveitis Busacca nodules (iris stroma) Iris Nodules Ø It is important to rule out infection, TB, and syphilis (TB and syphilis are masquerading diseases) Berlin nodules (angle) D. OCULAR DIAGNOSTICS **Good to know only** Ø Fluorescein angiography: CME, retinal vasculitis, retinal or choroidal NV, disc swelling, retinitis, choroiditis Ø Indocyanine green angiography: choroidal vasculopathies (white dot syndrome, VKH, SO), sarcoid; more on choroid problems Ø Ultrasound: vitreous opacities, choroidal thickening, retinal detachment, media opacities, small pupil Ø OCT: CME, subretinal fluid, CNV, photoreceptor IS-OS junction; to test for layers Ø Fundus autofluorescence: lipofuscin to assess viability of RPE/photoreceptor complex in white dot syndromes Ø Anterior chamber paracentesis: cell cytology, PCR Ø Vitreous biopsy +/- vitrectomy: cell cytology, PCR Choroidal Nodules Ø Chorioretinal biopsy IV. CLASSIFICATIONS OF UVEITIS Non-granulomatous: composed of lymphocytes, plasma cells and pigment Figure 12. Anatomic classification of uveitis, including anterior uveitis, Keratic Precipitates intermediate uveitis, posterior uveitis, and panuveitis (fine, white colored) A. ANTERIOR UVEITIS Ø Affects the front area of the uvea Ø Symptoms: o Pain o Redness o Photophobia: excessive tearing due to ciliary spasm o Decreased vision due commonly to macular edema Ø Signs: o Cells and flares in the anterior chamber § Cells – individual inflammatory cells, such as WBCs CERVA, DAGUITAN, DELA CRUZ, EMPERADOR, QUIDASOL, ROSETE, ABRENICA, RAPOSAS OPHTHALMOLOGY Page 4 of 15  OPHTHALMOLOGY P.08 Uvea Dr. Chiu-Ang | September 5, 2024 § Flares – protein that has released through Ø Nonspecific urethritis (can’t pee) inflamed vasculature inside the eye (parang “ting” Ø Oligoarticular polyarthritis (can’t ganun) climb a tree) o Ciliary flush (mapula na yung vessels) Reactive arthritis Ø Papillary conjunctivitis (can’t see) o Keratic precipitates – cellular deposits in the syndrome Ø Iritis corneal endothelium Ø Keratoderma blennorrhagicum Ø Causes Ø Circinate balanitis o Seronegative spondyloarthropathies / HLA-B27- Ø Typical skin findings (hyperkeratotic related: AS, Reiter’s, IBD, psoriatic arthritis rash) o Behcet’s disease Psoriatic arthritis Ø Nail changes o JRA Ø Sausage digits o Fuch’s heterochromic iridocyclitis Inflammatory Ø Iritis may precede bowel disease o Syphilis bowel disease Ø Sacroiliitis o TB (Ulcerative colitis/ o Sarcoidosis Chron disease) o Possner-Schlossman syndrome/CMV/herpetic iritis o Masquerade syndrome o Traumatic iritis o Tubular interstitial nephritis and uveitis o Toxic anterior segment syndrome o Idiopathic No work-up is necessary if first episode + non- granulomatous, + unremarkable ROS + PMHx due to it being most likely idiopathic 1. ACUTE NON-GRANULOMATOUS IRITIS/IRIDOCYCLITIS Ø Presents as sudden onset of pain, redness, and photophobia with or without decreased vision Ø Inflammation lasts several days to weeks, no more than 3 months Ø The attack is acute and unilateral with a history of episodes alternating between the 2 eyes (HLA-B27), or acute and bilateral (TINU, idiopathic, autoimmune, JIA, drug-induced) Figure 14. Triad of reactive arthritis Ø Idiopathic Ø Treatment: steroids (topical, periocular, oral), cycloplegics Figure 15. Chronic anterior uveitis with posterior and peripheral anterior synechiae in a case of HLA-B27 positive ankylosing spondylitis Figure 13. Acute anterior uveitis with plasmoid aqueous and hypopyon in a patient with ulcerative colitis 3. JUVENILE IDIOPATHIC/RHEUMATOID ARTHRITIS (JIA, JRA) Ø Chronic, non-granulomatous anterior uveitis 2. HLA-B27 RELATED UVEITIS Ø Iridocyclitis in JIA is most common in those with Ø Acute, recurrent, unilateral, alternating non- o Pauci-articular presentation (4 or fewer joints) granulomatous iritis or iridocyclitis (bilateral, chronic AU of arthritis in minority) o RF - Ø HLA-B27 positive in 50-95% cases o ANA + o Female gender Ø History of: o Onset of arthritis less than 5 years old o Morning lower back pain or Ø Oftentimes, eye is white and asymptomatic Ankylosing stiffness, which improves with Ø Fine KPs, cells and flare, band keratoptahy, white spondylitis exertion cataracts, posterior synechiae Ø Work-up: sacroiliac imaging (aortic valvular insufficiency, lung fibrosis) CERVA, DAGUITAN, DELA CRUZ, EMPERADOR, QUIDASOL, ROSETE, ABRENICA, RAPOSAS OPHTHALMOLOGY Page 5 of 15  OPHTHALMOLOGY P.08 Uvea Dr. Chiu-Ang | September 5, 2024 Ø Treatment: topical steroids + cycloplegics, early Ø Course: self-limiting (10%), remitting-relapsing course initiation MTX, oral/periocular steroids, adalimumab, (30%), prolonged course without exacerbations (60%) infliximab, biologics Ø Treatment: o You cannot give steroids as a long-term o Periocular steroids – first line treatment for children → use the o Intravitreal steroids in severe, refractory cases immunomodulatory drugs o Systemic steroids Ø IA patients should undergo periodic eye screening, o Indirect laser photocoagulation or cryotherapy frequency depends on number of risk factors