Opthalmology Week 1 - 3rd Year Ophthalmology Notes PDF

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3rd Year Ophthalmology Notes...

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Cl i ni calSki l l s( Opht hal mol ogy) Ophthalmic History Taking - Presenting Complaint: Front of eye: Pain, Redness, Discharge, Photophobia Back of eye: Flashers, Floaters, Shadows Diplopia: Monocular or binocular and whether it is Horizontal or Vertical Possible Causes of Diplopia Monocular:  Cataract  Myopic Binoculars:  Cranial Nerve palsy (3, 4, 6)  Trauma trapping of muscles  Myastia Gravis AChE  Hyperthyroidism  MS - Past ophthalmic history or surgery - Medical History - Drug Therapy (eye drops and any use of beta-agonist inhalers) - Family history (glaucoma, esp. if over the age of 40) - Occupation (driving) Ophthalmic Examination General observation:  Difference of pupil size  Ptosis  Globe deviation Visual acuity (6m):  Distance set, What they can see  Best Corrected Visual Acuity (BCVA)/ Unaided (Habitual UAVA), Which Eye, Child/Adult Eye movements:  Ask if there is any double vision  Slowly to the extremes  Hold chin / eyelids Visual fields: (testing for quadrant absent or present)  4 points each eye  Same distance  Point to the finger (Diagonal)

6/12 - 2 (means cannot see two letters in the row) Forget distance glasses (USE Pinhole) Amblyopia is decreased vision in one or both eyes due to abnormal development of vision in infancy or childhood e.g. causes: Lazy Eye/Squint/Corneal Scarring Reduce distance if cannot see (e.g. 1/60)  Counting fingers  Hand movements  Perception of light  No perception of light Colour Vision:  Congenital colour blindness  Acquired Ophthalmoscope:  Dim lights  Look at far end  Get close & Ask about eye drops  Red reflex (vitreous haemorrhage / cataracts) look straight in the light Direct and consensual response: Swinging movement (between left and right eye) for APD testing. If suspected acute closed-angle glaucoma: Thumb on eye ball -> rock solid hard.

Cor eSessi on1-Cat ar actLect ur e Biggest cause of sight loss in the world Lens transparency: Collagen Fibres Arrangement -> less diffractive effect Zonules = suspensory ligaments Anterior surface: Single layer of cells still proliferating Cortex outer: Still growing Nucleus: Adult cells Cornea has greatest refractive index. Cornea provide 45 Dioptres. Lens provide 15 Dioptres. Lens can accommodate. Presbyopia: - decreased with age - decreased ability to accommodate Some clinical features of Cataracts

- Lack of Red Light Reflex - May cause monocular diplopia Cataracts Classification: - Morphology (nuclear, subcapsular, within the sutures / cortical) - Age of onset - Cause (traumatic, drug) Posterior subcapsular (black bubbles with ophthalmoscope) Causes of posterior subcapsular cataract: uvitis, diabetes Age of onset - Congenital  Leucoria: white reflex  Amblyopia: decreased vision in one or both eyes due to abnormal development of vision in infancy or childhood. Maybe caused by refractive error, strabismus, rarely Cataracts - Infantile:  patients with down syndrome more prone - Senile  age Infection causes (TORCH Acronym) Toxoplasma, Others: (HIV, Syphillis), Rubella, CMV, Herpes Drugs causes: Steroids, Bisphosphonate, Amiodarone Treatment: Operation. Cataract surgery is an elective operation Phacoemulsification, preserving posterior capsule. Intra-ocular lens (not for infants, where aphakia lenses). Lens on anterior chamber (for zonules that are damaged) Aphakic glasses worse than contact lenses. Complications of cataract surgery: explain to patients: infection and vision loss explained to patients - Posterior capsule rupture - Vitreous loss - Intra Ocular Lens Problem - Increased IOP - Wound Leak - Endophthalmitis MEDICAL EMERGENCY - Corneal oedema - Posterior Capsular Opacification (proliferation of lens epithelium on Posterior capsule, due to growing fragments of lens) Rx: Laser surgery for complications. e.g. Posterior YAG Capsulotomy. Astigmatism / Refractive Error: Myopia / Hypermetropia

Femtosecond laser treatment is expensive, not cost-effective, and still requires surgeon to remove lens and place in new lens RE Right Eye LE Left Eye ua unaided BCVA best corrected visual acuity Hypopyon Leukocytic exudate in the eye (always think of Endophthalmitis)

Cor eSessi on2-RedEy e History: - Location (unilateral / bilateral) - Photosensitivity - Changes in Vision - Trauma - Contact Lens (slightly different types of microbes) Examination: - Visual acuity - Lymphadenopathy - Anterior to posterior (eye lash, lids, cornea, sclera, conjunctiva, anterior chamber) - Pupillary Response (reaction to light, and accommodation) - Fundoscopy - Eye movements Right Bell's Palsy (unable to blink, eyes prone to dryness) RA are more prone to uveitis, also immunosuppression can lead to infection Causes of red eye: Conjunctivitis: Bacterial Conjunctivitis (could be STDs, especially with presence of blood) *chlamydia can also affect new-born, usually affect eye unilaterally *gonococcal conjunctivitis can cause profuse purulent discharge - Viral (Rx usually not required) - Allergic (usually bilateral) Sub-conjunctival haemorrhage (usually trauma) - should check blood pressure - Rx usually not required. - do the eye movement to see if there are any more haemorrhage Episcleritis: (phenylephrine eye drops, vessels will constrict) Scleritis: (vessels don't blanch away with phenylephrine, can thin out sclera due to inflammation)

Very very painful Keratitis (inflammation of cornea) - Bacterial (Hypopyon) - Viral (steroids may make Herpes Simplex Keratitis worse!) / Fungus / Acanthaemoba (more common in contact lenses) *HSK will show branching green line with orange dye and cobalt blue light Iritis or Anterior Uveitis (inflammation around the pupil) - Rx topical steroids remember to ensure it's not HSK Symptoms: - Keratic precipitates (white dots behind the cornea) - Hypopyon Acute angle closure Glaucoma MEDICAL EMERGENCY tend to be in older person - fixed pupil – pupil tend to not dilate with light - very red eye - hazy cornea Herpes Zoster Ophthalmicus - shingles affect one side of the face - Hutchinson’s sign: Lesions to tip of nose-> increased chance ocular involvement

- Rx Acyclovir Endophthalmitis (infection inside the eye): MEDICAL EMERGENCY - Intra-vitreous injection of antibiotics - usually some procedures done to the inside of the eye (surgery) - usually take a few days - red eye, eye lid inflamed, pus inside the eye Trauma: - history of trauma is very important - cornea and fluorescein (cobalt blue light) tell if there is defect, and depth of injury - check under eyelid Partial Hyphaema (blood collection in eye) (Rx usually treatment not required, unless too much -> blockage of angle, hence check for IOP)

Complete Hyphaema (may lead to high IOP)

IOP Pressure Measurement: - Slit lamp: Goldmann Tonometer - Eyecare digital probe Iridodialysis (dislocated at the iris) Blow Out Fracture at the Maxillary Sinus (Inferior rectus can be trapped) Eyelid laceration - allow tear to flow and drain properly - involving eye lid margin (ask ophthalmologist to be involved) - involving the canaliculi Penetrating Eye Injuries: Seidel's test (Fluorescein, leakage means that dye is leaking out of the eye) Thermal injury Chemical Injuries: Flush out chemical agent, Check for pH, Clean under the eye-lid

Cor eSessi on3-Opt i cNeur opat hi es Features: - Reduced visual acuity - Afferent pupillary defect

- Visual field defect - Dyschromatopsia (unable to see some colours) - Decreased light and contrast sensitivity Signs: Optic Disc Changes - Atrophic (Pale) - Disc Swelling (loss of cupping) - Disc Cupping (in the middle of optic disc, normal ~0.2) Optic disc always near the nasal side Describe: Colour, Contour, Cupping

Investigation: - Automated Perimetry - MRI - Visual electrophysiology (detect optic nerve function) - Fluorescein Angiography Central retinal vein occlusion: - flame haemorrhage - disc swelling CD Ratio: - open angle glaucoma, nerve cells dying Optic disc atrophy: - death of optic nerve, maybe partial or complete - usually due to chronic injury

MRI T1 = water is dark (e.g. vitreous will be hypointense) T2 = water is bright (e.g. vitreous will be hyperintense) Optic Neuritis sub classification of Optic Neuropathy - inflammation of optic nerve - causes: demyelinating (common, e.g. MS), infections - ophthalmoscope:  Retrobulbar Neuritis  Papillitis  Neuroretinitis Anterior Ischaemic Optic Neuropathy - Non-arteritic Small emboli in the eye, similar to stroke (non-emergency) - Arteritic (emergency) GCA = Giant Cell Arteritis = Temporal Arteritis (inflammation in the temporal artery)  older people  temporal headache  loss of vision that may be transient  jaw claudication (pain after chewing)  weight loss fatigue Rx: Start on steroids on the same day Papilloedema: - Swollen disc but due to increased Intra-cranial Pressure - Colour of disc hyperaemic (red) - Bilateral to be affected - Optic nerve (also affected by increased CSF) - Horizontal diplopia (CNXI also affected by increase in ICP) - Absence of vein pulsation APD: Afferent Pupillary Defect: Both eyes may not constrict / constrict equally less (Afferent) Adie's Pupil: due to inflammation or damage to the ciliary ganglion Near light dissociation: constrict to accommodation does not constrict to light also reduced peripheral reflex (e.g. Knee Jerk) Argyll Robertson (Prostitute Pupils) Similar as Adie's, but is associated with neurosyphilis

Horner's syndrome - Myotic pupils (constricted pupils) - Ptosis - Reduced sweating - Congenital Heterochromia - Smoking (Pancoast tumours at the apex of lung, compress sympathetic pathway) Learn to describe visual field defects towards the brain, the more symmetrical the visual field defect

Cor eSessi on4-Ocul arTr auma Look at ALL aspect of the eye Anterior segment:  Eye-lid  Cornea  Pupils Types of ocular trauma:  Iridodialysis (detachment of iris)

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Ciliary body may react to shock Hyphaema (prescribe oral steroids) Traumatic Cataract Dislocated lens Vitreous Haemorrhage Hole in macula (perforation?) Siedel's Test (Open full / Close partial sclera injury)

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Optic Neuropathy Blowout fracture (especially between the orbital floor and maxillary sinus)

Cor eSessi on5-Di abet i cRet i nopat hy Diabetes Risk Factors  Diabetes also affect cornea (affect the nerves)  Cataracts  Cranial Nerves 3, 4, 6 palsies (also cause diplopia) Common cause of blindness in the UK Pathogenesis of DR  Hyperglycaemia, effects on nerve tissues and blood vessels  Capillary basement membrane thickened  Capillaries close Blood vessel Changes

Background Diabetic Retinopathy - Microaneurysm - Dot & Blot Haemmorhage - Exudates - also note Venous Looping Try to test yourself in identifying the features

Pre-proliferative Retinopathy - Cotton wool spots Proliferative Retinopathy - New vessels lack supporting structures NVD - Neovascularisation at the Disc NVE - Neovascularisation elsewhere !!Common OSCE Question!! Pan retinal photocoagulation -> destruction of peripheral blood vessels - recent laser (white spots) - old laser (black spots) anti-VEGF is shown to be more effective in maculopathy, anti-VEGF needs to be administered more than once End-stage / Advanced Retinopathy -> bleeding into the vitreous - blood floaters - blurred vision -> fibrosis pulls and detaches retina Diabetic Maculopathy can occur at any stage Diabetic Maculopathy - Ischaemic (Geographic Atrophy) Rx: No treatment currently - Oedematous (Macular Exudates) Pathogenesis - fibrovascular tissue bursts from the choroid, through Bruch’s membrane and invades the overlying retina - fluid and haemorrhage destroys the retinal structures Rx: Intravitreal Injections of Anti-VEGF Fluorescent Angiogram - shows presence of new blood vessels - also shows leakage of blood vessels OCT reflection of beam of light shown into patient's eye - May see collection of fluid in macula - Due to leakage from damaged blood vessels Risk Factors - Sudden fluctuations in blood glucose - Duration of diabetes - Pregnancy (hormonal changes, more likely to cause neovascularisation)

- Not having Eye Clinical Screening (DR is asymptomatic)

Cor eSessi on6-AgeMacul arDegener at i on Optic nerve is located nasally

AMD Clinical Features Deterioration of central vision, usually peripheral vision is left intact Early AMD Drusen = little lipoproteinous bumps between choroid and retina looks like exudates, round and in the macula Exudates are smaller and more defined, possibly retinal vein occlusion. Think of diabetic retinopathy in diabetic patients. Pigment increase the risk of developing to advanced AMD Advanced AMD Dry Macular Degeneration - Atrophy of Retina, tend to be RPE - Retinal Pigmented Epithelium in the macula - Causes geographic atrophy, lead to blindness in the corresponding part of visual field - Occurs gradually

Wet Macular Degeneration - Choroidal neovascularisation and leakage - More rapid - Fibrovascular membrane burst through choroid, and leaks between choroid and retina - Destroys structure and layers of retina Rx: Intraviterous Anti-VEGF Drug name: Eylea (Aflibercept) or Lucentis (Ranibizumab) Signs: - Red (haemorrhage of new vessels) and Yellow Blots (exudates) - Drusen Metamorphopsia: Distortion of vision, due to distortion of shape of macula, and finally distort perceptions Investigations of AMD - OCT - Optical Coherence Tomography - FFA - Fluorescin Angiography Causes of AMD - Genetics - Age - Smoking - UV exposure through bright lights Painless Gradual Vision Loss Reversible - Cataract - Refractive Error / Astigmatism - Diabetic Macular Oedema Irreversible - AMD (wet / dry) - Temporal Arteritis - Vitreous haemorrhage - Retinal detachment - Central retinal artery occlusion - Retinal vein occlusion - Optic Atrophy - Open angle glaucoma - Retinitis Pigmentosa Charles Bonnet syndrome (CBS), is the experience of complex visual hallucinations in a person with partial or severe blindness.

Cor eSessi on7–Gl aucoma

Cataracts - leading blindness in the world Age-related maculopathy - Biggest cause of blindness in Northern Ireland Glaucoma - biggest cause of irreversible cause of blindness Age is a big risk factor of glaucoma Prevalence highest in elderly Primary: Unknown Cause Secondary: Specific Cause Open Angle Acute-Closure Angle: Iris blocks the angle (due to increase swelling) Gonioscopy (angle lens): Allow viewing of the angle Primary Open-Angle Glaucoma: - Asymptomatic - Tend to present late - People who visit their optometrist may have it detected - Irreversible Definition of glaucoma: optic neuropathy with disc swelling, affecting peripheral vision - frequently inherited - glaucoma is NOT the same as high intraocular pressure - however, treatment only deals with high intraocular pressure Observation - disc become pallor - disc cupping is increasing (ratio of disc to cup ratio) / thinning of neural retinal ring (to measure you can divide into 4 quadrants, and add up the vertical height) - disc contour less defined - vessels are pushed towards one side

Treatment - Eye drops (prostaglandin, beta-blockers) - Trabeculotomy (Surgical) (Trabeculotomy bleb blister, fluid can come out of the eye) - Trabeculoplasty (Laser) Peripheral loss tends to be patchy (less helpful doing visual field by confrontation, better with automated periphery test) Angle Closure Glaucoma - Chronic (less dramatic) - Acute Symptoms  Very red eye  Tend to be elderly  Vagal response, nausea or vomiting  Extreme pain Pathology: - lens blocks pupil, unable to drain aqueous fluid into the angle - swelling of the iris, blocks angle - hypermetropic people have higher chance, myopic eyes have lesser chance - more common in women (maybe smaller eyes)

Clinical Signs: Dilated pupils that does not respond to light (direct or consensual) Rx: Trabeculoplasty Secondary Causes: - Pseudo exfoliation - Rubeosis: retinal ischaemia, neovascularisation of iris - Iris Bombe: due to iritis, pupils stick to the iris Congenital glaucoma: - Big eyes of babies - Photophobic (scared of light) - Watery Eyes Rx: Surgery is very important -> may lead to complications in the eye

Opht hal mi cI magi ngTechni ques Describe normal and abnormal OCT: Neovascular membrane, Oedema Describe normal and abnormal FFA: Neovascular retinal vessels, Oedema Ophthalmoscope: Optic disc Nasal, Macula Temporal

RPE between retina and choroid. Retinal vessels and choroidal vessels are different! Diabetic Retinopathy v.s. Maculopathy Non-Mydriatic Camera Central Retinal Vein Occlusion (Haemorrhage very diffuse) Vitreous Haemorrhage (obscure view of retina) Fluorescein Angiography: - different stage, different vessel filling - photos taken at different timing - potential side effects: Anaphylaxis Shock, Syncope, Cardiac Arrest Optical Coherence Tomography: - Hyperreflectivity (Nerve Cells, Outer plexiform Layer, Plexiform Layer, Retinal Pigment Epithelium) BRIGHT - Hyporeflectivity (Outer nuclei of photo receptors, Inner nuclei of bipolar cell, Retinal Capillaries) DARK - Central fovea Diabetic Retinopathy

FFA = New Vessels OCT = Cystoid Macular Oedema, Supratemporal, Hyper reflective Maculopathy OCT = Fluid collection between choroid and retina...