Medical Retina Flashcards
What is the vitreous cavity in the retina?
LARGEST CAVITY 4.0-4.4 ML IN ADULTHOOD
CONTAINS VISCOELASTIC GEL MADE OF MOSTLY WATER
CONTAINS MAINLY HYALURONIC ACID AND TYPE II COLLAGEN
What is the vitreous derived from?
Embryologically from the diencephalon
What does the diencephalon give rise to?
Optic vesicle and then optic cup
What are the two layers of the retina?
Retinal Pigment Epithelial Layers
Neurosensory Retina
Why does retinal detachment occur?
weak connection between RPE and NSR
What are the 9 layers of the retinal pigment epithelium? (Internal to external)
- Internal limiting membrane
- Nerve fibre Layers
- Ganglion cell layer
- Inner plexiform layer
- Inner nuclear layers
- Outer plexiform layer
- Outer nuclear layer
- External limiting membrane
- Photoreceptor layer
What is the function of the internal limiting membrane?
SEPARATES THE RETINA FROM THE VITREOUS
What is the function of the nerve fibre layer?
CONTAINS GANGLION CELL AXONS THAT COME TOGETHER TO FORM THE OPTIC NERVE,
PRESENT IN THE MACULAR AREA AND TRAVELS NASALLY TO THE OPTIC NERVE DIRECTLY THROUGH THE PAPILLOMACULAR BUNDLE
What is the function of the ganglion cells layer?
CONTAINS THE CELL BODIES OF THE GANGLION CELLS, INVOLVED IN TRANSMITTING VISUAL INFORMATION TO THE BRAIN INCLUDING STIMULUS REQUIRES FOR LIGHT PUPILLARY RESPONSE
What is the function of the inner plexiform layer?
SYNAPTIC LAYER BETWEEN SECOND AND THIRD ORDER NEURONS
What is the function of the inner nuclear layer?
CONTAINS CELL BODIES OF BIPOLAR CELLS AND CELL BODIES OF MULLER CELLS
What is the function of the outer plexiform layer?
SYNAPTIC LAYER BETWEEN PHOTORECEPTORS AND BIPOLAR CELLS
What is the function of the outer nuclear layer?
CONTAINS CELL BODIES OF RODS AND CONES
What is the function of the external limiting membrane?
CONNECTIONS BETWEEN PHOTORECEPTORS AND MULLER CELLS CREATE THE ELM
What is the function of the photoreceptor layer?
contains rods and cones
What is the RPE composed of?
SINGLE LAYER OF A CUBOIDAL EPITHELIAL CELLS CONTAINING MELANOSOMES AND HAS MANY FUNCTIONS
What are the functions of the RPE?
ABROBS LIGHTS AND PREVENTS THE SCATTERING OF LIGHT WITHIN THE EYE
REPLENSIHES THE MOLECULES NEEDED FOR PHOTOTRANSDUCTION
CONTAINS A BLOOD RETINAL BARRIER WHICH PROVIDES A SELECTIVELY PERMEABLE MEMBRANE TO SUPPLY NUTRIENTS TO THE PHOTORECEPTORS AND MAINTAIN HOMEOSTASIS
-BLOOD RETINAL BARRIER IS MAINTAINED BY THE ZONULAE OCCLUDENTES
PHAGOCYTOSIS OF PHOTORECEPTOR OUTER SEGMENT MEMBRANES
TRANSPORT AND STORAGE OF METABOLITES AND VITAMINS
What is the macula lutea?
MACULA IS PIGMENTED, ROUNDED AREA AT THE POSTERIOR POLE OF THE RETINA, LOCATED TEMPORAL TO THE OPTIC DISC
What is the macula lutea made of?
SEVERAL LAYERS OF GANGLION CELLS (peripheral retinal only has one layer of ganglion cells)
What is the fovea?
DEPRESSION AT THE CENTRE OF THE MACULA THAT CONTAINS ONLY CONES AND REPRESENTS THE RETINA’S HIGHEST VISUAL ACUITY
What is unique about the centre of the fovea?
CENTRE OF THE FOVEA IS AVASCULAR AND IS DEPENDENT ON THE UNDERLYING CHORIOCAPILLARIS FOR BLOOD SUPPLY VIA DIFFUSION
How many rods are there?
120 million
How many cones are there?
6 million
What is the pigment in rods?
rhodopsin
What is the pigment in cones?
iodopsin
What is the wavelength of maximum absorbance in rods?
498
What is the wavelength of maximum absorbance in cones?
SHORT (420) - blue
MEDIUM (534) - green
LONG (564) - red
Describe the bipolar connection of rods
ONE BIPOLAR CELL CAN RECEIVE STIMULI FROM MULTIPLE RODS
Describe the bipolar connection of cones
FORMS A 1:1 RATIO WITH BIPOLAR CELLS
Describe the function of rods
SENSITIVE IN DARK-DIM ILLUMINATION
RESPONSIBLE FOR NIGHT AND PERIPHERAL VISION
Describe the function of cones
SENSITIVE TO BRIGHT LIGHT
RESPONSIBLE FOR CENTRAL AND COLOUR VISION
Describe the blood supply to the retina
OUTER THIRD OF RETINAL LAYERS, INCLUDING PHOTORECEPTORS AND RPE ARE SUPPLIED BY THE SHORT POSTERIOR CILIARY ARTERY
INNER TWO THIRD OF RETINAL LAYERS ARE SUPPLIED BY THE CENTRAL RETINAL ARTERY
Describe the variation in blood supply to the retina
N SOME PATIENTS, THE INNER LAYER OF THE MACULA MAY HAVE A DUAL BLOOD SUPPLY BY THE CILIORETINAL ARTERIES (BRANCH OF THE SHORT POSTERIOR CILIARY ARTERY
WHEN UNAFFECTED, CENTRAL VISION MAY BE CONSERVED IN CASES OF CENTRAL RETINAL ARTERY OCCLUSION (CRAO)
What is the most common microvascular complication of diabetes?
diabetic retinopathy and maculopathy
What is the most common cause of blindess in in adults aged 35-65 in developed countries?
diabetic retinopathy and maculopathy
Describe the pathogenesis of diabetic retinopathy and maculopathy
HYPERGLYCAEMIA CAUSES INCREASED RETINAL BLOOD FLOW AND DAMAGE TO ENDOTHELIAL WALLS AND PERICYTES
ENDOTHELIAL DYSFUNCTION CAUSES VASCULAR PERMEABILITY AND HARD EXUDATIVE FORMATION (LIPOPROTEINS IN THE OUTER PLEXIFORM LAYER)
PERICYTE DAMAGE PREDISPOSES TO THE FORMATION OF MICROANEURYSMS, WHICH ARE LEAKAGES OF BLOOD FROM CAPILLARY WALLS AND FLAME HAEMORRHAGES DUE TO RUPTURE OF THE CAPILLARY WALLS WHICH TRACK ALONG THE NERVE FIBRE LAYER
COTTON WOOL SPOT FORMATION: AXONAL DEBRIS AT MARGINS OF ISCHAEMIC INFARCTS
NEOVASCULARISATION OCCURS THROUGH ANGIOGENIC FACTORS SUCH AS VASCULAR ENDOTHEALIAL GROWTH FACTORS IN RESPONSE TO ISCHAEMIA
CYSTOID MACULAR OEDEMA: MOST LAYERS CAN BE AFFECTED PARTICULARLY THE OUTER PLEXIFORM LAYER
What is the most important risk factor in the development of diabetic retinopathy and maculopathy?
duration of diabetes
What are the risk factors for diabetic retinopathy and maculopathy?
duration of diabetes
diabetic control
pregnancy
smoking
hyperlipidaemia
hypertension
What are the features of diabetic retinopathy and maculopathy?
MOST PATIENTS WILL BE ASYMPTOMATIC
CAUSES OF VISION LOSS INCLUDE:
GRADUAL ONSET:
- ANY TYPE OF DIABETIC RETINOPATHY
- DIABETIC MACULAR OEDEMA: MOST COMMON CAUSE OF VISUAL IMPAIRMENT
- CATARACT
ACUTE ONSET:
- PAINLESS: SIMILAR TO VITREOUS HAEMORRHAGE OR TRACTIONAL RETINAL DETACHMENT (FLASHES AND FLOATERS MAY PRECEDE VISUAL LOSS)
- PAINFUL: SIMILAR OT NEOVASCULAR GLAUCOMA PRECIPITATED BY RUBEOSIS IRIDIS
How is DR classified?
MODIFIED AIRLINE HOUSE Classification
describe mild non-proliferative DR
AT LEAST ONE MICROANEURYSM
INRTARETINAL HAEMORRHAGES
EXUDATES
COTTON WOOL SPOTS
describe moderate non-proliferative DR
INTRARETINAL HAEMORRHAGES (IN 1-3 QUADRANTS) OR MILD INTRARETINAL MICROVASCULAR ABNORMALITY
VENOUS BEADING (IN 1 QUADRANT ONLY)
Describe severe non-proliferative DR
FOLLOWS THE 4-2-1 RULE; ONE OR MORE OF
INTRARETINAL HAEMORRHAGES IN 4 QUADRANTS
VENOUS BEADING > 2 QUADRANTS
MODERATE IRMA > 1 QUADRANT
Describe non high risk proliferative DR
NEOVASCULARISATION ON DISC OR ELSEWHERE
Describe high risk proliferative DR
FULFILS ONE OF THE FOLLOWING
NV > 1/3 DISC AREA
NVD (neovasc disc) PLUS VITREOUS HAEMORRHAGE
NVE (neovasc elsewhere) > ½ DISC AREA PLUS VITREOUS HAEMORRHAGE
Describe advanced proliferative DR
Tractional retinal detachment
What is diabetic maculopathy?
PRESENCE OF DIABETIC MACULAR OEDEMA
How is diabetic maculopathy classified?
CENTRE INVOLVING DIABETIC MACULAR OEDEMA OR
EXTRA-FOVEAL DIABETIC MACULAR OEDEMA MEETING CLINICALLY SIGNIFICANT MACULAR OEDEMA DEFINED BY THE ETDRS
What investigations are used for diabetic maculopathy?
OPTICAL COHERENCE TOMOGRAPHY FOR ASSESSING AND MONITORING DMO
FLUORESCENCE ANGIOGRAPHY MAINLY USED TO ASSESS FOR RETINAL ISCHAEMIA
What is the management of diabetic maculopathy?
GLYCAEMIC AND BLOOD PRESSURE CONTROL (USE FOR EFFECTIVE ANTIHYPERTENSIVES SUCH AS LISINOPRIL)
What is the management of non proliferative dr
MONITORING IN SCREENING PROGRAMMES OR SECONDARY CARE RANGING FROM ANNUAL (FOR MILD-MODERATE) TO 4MONTHLY SEVERE
CONSIDER PAN RETINAL PHOTOCOAGULATION (PRP) FOR SEVERE NONPROLIFERATIVE IN ELDERLY PATIENTS WITH TYPE 2 DIABETES OR IF POOR ATTENDANCE OR PRIOR TO CATARACT SURGERY
What is the management for non high risk proliferative dr?
REGULAR ROUTINE REVIEW +/- PRP
What is the management for high risk proliferative DR?
PRP WITHIIN TWO WEEKS
TREAT DMO IF COEXISTS AT THE SAME TIME OR BEFORE
What is the management for vitreous haemorrhage?
TREAT AS HIGH RISK Proliferative DR
What is the management for traction retinal detachment or persistent vitreous haemorrhage?
PARS PLANA VITRECTOMY
What is the treatment for maculopathy?
TREATED WITH INTRAVITREAL ANTI-VEGF (RANIBIZUMAB OR AFILBERCEPT, NOT THE LATTER HAS A HIGHER MOLECULAR WEIGHT AND IS SECOND LINE) IF THERE IS DMO ON OCT AND THE VISION AFFECTED
CONSIDER USING MODIFIED ETDRS LASER IF ANTI-VEGF IS CONTRAINDICATED (E.G. PREGNANCY)
DIABETIC RETINOPATHY AND CATARACT SURGERY: TREAT Clinically significant macular oedema AND PDR OR NEOVASCULARISATION OF IRIS BEFORE CATARACT SURGERY
IF THERE IS NO FUNDAL VIEW PERFORM B SCAN ULTRASOUND
What is hypertensive retinopathy?
chronic hypertension - atherosclerotic changes and vasoconstriction - endothelial damage –> retinopathy
CHRONIC HYPERTENSIVE RETINOPATHY CAN INCLUDE SIMILAR SIGNS TO DIABETIC RETINOPATHY
How is Hypertensive Retinopathy managed?
BP control
What are the stages of hypertensive retinopathy?
ARTERIOLAR NARROWING
ARTERIOVENOUS NIPPING (FIGURE 14.3) OR ATHEROSCLEROSIS WITH THICKENING OF RETINAL ARTERIOLES (‘COPPER / SILVER WIRING’)
STAGE 2 PLUS FLAME HAEMORRHAGES, COTTON WOOL SPOTS OR EXUDATES
STAGE 3 PLUS PAPILLOEDEMA
What other vascular conditions is hypertension associated with?
RETINAL ARTERY AND VEIN OCCLUSION AND COMPOUNDS COMPLICATIONS OF DIABETIC RETINOPATHY
What is retinal vein occlusion?
SECOND MOST COMMON RETINAL VASCULAR DISORDER AFTER DIABETIC RETINOPATHY
How is retinal vein occlusion classified?
CENTRAL RETINAL VEIN OCCLUSION VERSUS BRANCH RETINAL VEIN OCCLUSION: AN OCCLUSION AT OR PROXIMAL TO THE LAMINA CRIBROSA WHERE THE RETINAL ARTERY EXITS THE EYE LEADS TO CRVO
AN OCCLUSION OF ONE OF THE BRANCHES OF CENTRAL RETINAL VEIN LEADS TO BRVO
ISCHAEMIC VS NON ISCHAEMIC
What are the risk factors for retinal vein occlusion?
AGE
MICROVASCULAR: HYPERTENSION, HYPERLIPIDAEMIA AND DM
COMBINED ORAL CONTRACEPTIVE PILL
GLAUCOMA
Describe non-ischaemic central retinal vein occlusion
SUDDENT, PAINLESS dVA (>6/60)
FUNDOSCOPY: TORTUOSITY AND DILATATION OF ALL BRANCHES OF CENTRAL RETINAL VEIN, DOT/BLOT AND FLAME HAEMORRHAGES OF ALL FOUR QUADRANTS, PROMINENTS IN THE PERIPERHY WITH OPTIC DISC AND MACULAR SWELLING
Describe ischaemic central retinal vein occlusion
SUDDENY, PAINLESS SEVERE dVA (6/60)
RELATIVE AFFERENT PUPILLARY DEFECT
SIGNIFICANT TORTUOSITY AND DILATATION OF ALL FOUR QUADRANTS WITH SEVERE FLAME HAEMORRHAGES, DISC AND MACULAR OEDEMA
RUBEOSIS IRIDIS IN ABOUT 50% OF PATIENTS WHICH CAN LEAD TO NVG
What is the most common location of branch retinal vein occlusion?
SUPEROTEMPORAL, FOLLOWED BY INFEROTEMPORAL
describe the features of branch retinal vein occlusion
DVA, METAMORPHOPSIA, VF DEFECT (ALTITUDINAL)
RETINAL HAEMORRHAGE IN AFFECTED QUADRANT
What are the complications of branch retinal vein occlusion?
CMO AND NEOVASCULARISATION
What is the management for branch retinal vein occlusion?
MACULAR OEDEMA WITH MINIMAL ISCHAEMIA
- WITHIN 3 MONTHS OF ONSET: CONSIDER OZURDEX OR ANTI-VEGF
- AFTER 3 MONTHS OF ONSET: CONSIDER MACULAR GRID LASER OF OZURDEX OR ANTI-VEGF
MACULAR OEDEMA WITH MARKED ISCHAEMIA: NO IMMEDIATE TREATMENT
ISCHAEMIC BRVO WITH NEOVASCULARISATION: PRP
What is retinal artery occlusion?
OPTHALMIC EMERGENCY
What is the most common cause of retinal artery occlusion?
Atheroscleorisis and GCA
Describe the features of central retinal artery occlusion
SUDDEN PAINLESS LOSS OF VISION (VA USUALLY COUNTING FINGERS, UNLESS CILIORETINAL IS SPARED) WITH MARKED RAPD
Describe the fundoscopy findings of central retianl artery occlusion
FUNDOSCOPY:
- SWOLLEN, PALE AND OPAQUE RETINA, -‘CHERRY RED’ SPOT AT THE MACULE
- ARTERIOLAR ATTENUATION
Describe the management of central retinal artery occlusion
IRREVERSIBLE RETINAL INFARCTION USUALLY OCCURS WITHIN 90 MINUTES OF OCCLUSION OF THE ARTERY:
THUS OCULAR MASSAGE,
Anterior Chamber PARACENTESIS,
IOP-LOWERING INTERVENTION SUCH AS IV ACETAZOLAMIDE OUTSIDE OF THIS WINDOW HAVE QUESTION EFFICACY
Describe features of branch retinal artery occlusion
MOST COMMONLY DUE TO EMBOLIC CAUSES
SUDDEN PAINLESS ALTITUDINAL FIELD LOSS
SWOLLEN WHITE RETINA ALONG THE AFFECTED VESSEL WITH ARTERIOLAR ATTENUATION
What is ocular ischaemic syndrome?
can be thought of as angina of the eye
MAJORITY OF CASES CAUSED BY ATHEROSCLEORTIC-STENOSIS OF THE CAROTID ARTERY
Describe the features of ocular ischaemic syndrome
UNILATERAL SUBACUTE dVA AND PERIOCULAR PAIN
ANTERIOR SEGMENT: CONJUNCTIVAL INJECTION, AC CELLS AND RUBEOSIS IRIDIS (IOP MAY REMAIN LOW DUE TO HYPOPERFUSION)
POSTERIOR SEGMENT: CAN BE DECEPTIVELY SIMILAR TO CRVO, CHERRY RED MACULA, RETINAL ARTERY ATTENUATION AND ENOVASCULARISATION OF THE DISC ARE SEEN
Describe non proliferative sickle cells changes to the eye
INCLUDES SIGNS OF INTRARETINAL HAEMORRHAGES (‘SALMON PATCHES’) OR PATCHES OF RPE HYPERPLASIA (BLACK SUNBURSTS)
Describe proliferative sickle cell changes to the eye
PERIPHERAL ARTERIOLAR OCCLUSION
ARTERIOVENOUS ANASTOMOSIS
NEOVASCULARISATION WITH A ‘SEA FAN’ APPEARANCE
VITREOUS HAEMORRHAGE
TRACTIONAL / RHEGMATOGENOUS RETINAL DETACHMENT
what IS THE LEADING CAUSE OF BLINDNESS IN THE ELDERLY IN DEVELOPED COUNTRIES ?
age related macular degeneration
What is the hallmark of age related macular degeneration?
LARGE CONFLUENT SOFT DRUSEN
How does cell death occur in age related macular degeneration?
apoptosis
Describe the pathological changes in dry age related macular degeneration
DRUSEN: YELLOW DEPOSITS BETWEEN BRUCH’S MEMBRANE AND RPE
ATROPHY OF RPE, PHOTORECEPTOR LAYERS ANC CHORIOCAPILLARIES
GEOGRAPHIC ATROPHY: THE END POINT OF DRY ARMD, CHARACTERISED BY LARGE ATROPHIC AREAS WITH VISIBILITY OF UNDERLYING CHOROID
Describe the pathological changes in wet age related macuular degeneration
INGROWTH OF CHOROIDAL VESSELS INTO RPE AND SUBRETINAL SPACE (CHOROIDAL NEOVASCULARISATION)
DISCIFORM MACULAR DEGENERATION IS THE END POINT OF WET ARMD
THIS IS FIBROUS SCARRING DUE TO SUB-RPE NEOVASCULARISATION (SUBRETINAL FIBROSIS)
Describe the pathological changes in polypoidal choroidal vasculopathy
A VARIANT OF WET ARMD
CHARACTERISED BY POLYPOIDAL DILATTION OF THE CHOROIDAL VASCULATURE
PROGRESSES TO SUBRETINAL HAEMORRHAGE AND MULTIPLE PEDs
MORE COMMON IN MIDDLE AGED ASIAN POPULATION AND IS UNILATERAL IN PRESENTATION
What are the risk factors for age related macular degeneration
INCREASING AGE: MOST IMPORTANT RISK FACTOR
GENETICS: CFH AND ARMS2 GENES
SMOKING
HYPERMETROPIA
HYPERTENSION
FEMALE
WHITE RACE
What are the features of dry age related md
GRADUAL dVA AND CENTRAL SCOTOMA
INTERMEDIATE OR LARGE SOFT DRUSEN (>63 MICRONS OR >125 MICRONS) NOTE: SMALL, HARD DRUSEN ARE OF LIMITED SIGNIFICANCE AND MAY REFLEXT NORMAL AGE-RELATED CHANGES
GEOGRAPHIC ATROPHY OF RPE
What are the features of wet age related md?
DECREASED VA, METAMORPHOPSIA AND CENTRAL SCOTOMA OF SUDDEN ONSET
SUBRETINAL OR SUB-RPE HAEMORRHAGE AND EXUDATION
RPE AND OR EXUDATIVE RETINAL DETACHMENT
CMO
SUBRETINAL FIBROSIS
What investigations are used in age related md
OCT: MOST WIDLEY USED TEST TO MONITOR DISEASE PROGRESS
ICG IF PCV SUSPECTED: BRANCHING VASCULAR NETWORK MAY BE SEEN ON EARLY FRAMES WITH HYPERFLUORESCENCE POLYPS IN LATE FRAMES
How is dry age related md managed?
INVOLVES MANAGEMENT OF MODIFIABLE RISK FACTORS
AGE RELATED EYE DISEASE STUDY 2 (9): VITAMIN C, VITAMIN E, LUTEIN, ZEAXANTHIN AND ZINC PROVIDED TO REDUCE THE PROGRESSION OF ARMD
AMSLER GRID: TO RULE OUT PROGRESSION TO WET ARMD
How is wet age related md managed?
INTRAVITREAL ANTI-VEGF INJECTIONS (E.G. RANIBIZUMBA OR AFLIBERCEPT)
What are two aids for low vision?
MAGNIFIERS: FOR READING E.G. LOOP OR SPECTACLE MAGNIFIERS
TELESCOPES: FOR DISTANCE VISION E.G. GALILEAN TELESCOPES
What is choroidal neovascularisation?
ABNORMAL GROWTH OF VESSELS FROM THE CHORIOCAPILLARIES THROUGH BRUCH MEMBRANE INTO SUB-RPE (TYPE 1) OR SUBRETINAL (TYPE 2) SPACE
Describe the presentation of choroidal neovascularisation
DVA, METAMORPHOPSIA AND SCOTOMA
What are the causes of choroidal neovascularisation?
DEGENERATIVE: ARMD (MOST COMMON CAUSE) MYOPIC DEGENERATION AND ANGIOID STREAK
CENTRAL SEROUS CHORIORETINOPATHY
INFLAMMATORY CONDITIONS: BIRDSHOT CHOROIDOPATHY, VKH, POHS
BEST DISEASE
IDIOPATHIC
What is degenerative myopia?
DEGENERATIVE CHANGES MAY OCCUR IN PATIENTS WITH PROGRESSIVE / PATHOLOGICAL MYOPIA
THOSE ARE A SUBSET OF PATIENTS WITH MYOPIA > -6D IN WHICH THE AXIAL LENGTH OF THE EYE MAY NEVER STABILISE
What disease is degenerative myopia associated with?
STICKLER, MARFAN, EHLERS-DANLSO AND DOWN SYNDROMES
What are the features of choroidal neovascularisation?
CHOROIDAL ATROPHY WITH VISIBILITY OF UNDERLYING CHOROIDAL VESSELS
CNV
RHEGMATOGENOUS RETINAL DETACHMENT
MACULAR HOLE
POSTERIOR STAPHYLOMA
What is a posterior staphyloma?
AN OUTPOUCHING OF THE POSTERIOR WALL OF THE EYE THAT HAS A DIFFERENT RADIUS OF CURVATURE THAN THE REST OF THE EYE
ONE OF THE HALLMARKS OF PATHOLOGICAL MYOPIA, ASSOCIATED WITH POOR PROGNOSIS
What are angiooid streaks?
USUALLY BILATERAL SYMMETERICAL IRREGULAR ATROPHIED STREAKS DEEP TO THE RETINA, RADIATING FROM THE OPTIC DISC
RESULT FROM BREAKS IN THE BRUCH MEMBRANE
How do angioid streaks present?
PERIPAPILLARY ATROPHY WITH MULTIPLE IRREGULAR STREAKS RADIATING IN A CIRCULAR PATTERN
What are some causes of angioid streaks?
IDIOPATHIC
PSEUDOXANTHOMA ELASTICUM: MOST COMMON SYSTEMIC ASSOCIATION
MUTATIONS IN THE ABCC6 GENE
PRESENTS WITH YELLOW PAPULAR LESIONS WITH EXCESSIVE WRINKLING (PLUCKED CHICKEN APPEARANCE) OF SKIN USUALLY IN THE NECK, INGUINAL FOLDS AND ANTECUBITAL FOSSA
EHLER-DANLOS SYNDROME
PAGET DISEASE
What is cystoid macular oedema?
RETINAL THICKENING OF THE MACULA DUE TO ABNORMALITIES OF THE BLOOD RETINAL BARRIER WHICH LEADS TO LEAKAGE OF FLUID WITHIN THE INTRACELLULAR SPACES OF THE RETINA, TYPICALLY IN THE OUTER PLEXIFORM LAYER
What are some symptoms of cystoid macular oedema?
dVA, METAMORPHOPSIA AND SCOTOMA
What investigation is used in cystoid macular oedema?
OCT
What are some causes of cystoid macular oedema?
DIABETIC MACULE OEDEMA
CRVO AND BRVO
ARMD
UVEITIS TYPICALLY PARS PLANITIS BUT ALSO OCCURS IN ANTERIOR AND POSTERIOR UVEITIS
RETINITIS PIGMENTOSA
IRVINE-GASS SYNDROME
DRUGS
What is central serous chorioretinopathy?
BUILDUP OF CENTRAL SUBRETINAL FLUID DUE TO RETINAL PIGMENT EPITHELIUM DYSFUNCTION AND CHOROIDAL HYPERPERMEABILITY
What are some risk factors for central serous chorioretinopathy?
MALES AGED 20-50
TYPE A PERSONALITY
CORTICOSTEROID RELATED: IATROGENIC OR CUSHING DISEASE
What are some features of central serous chorioretinopathy?
UNILATERAL DROP IN VA METAMORPHOPSIA, CENTRAL SCOTOMA
SLOW RECOVERY FROM BRIGHT LIGHT
COMPLICATIONS INCLUDE SEROUS (EXUDATIVE) RD AND CNV
What are the investigations used for central serous chorioretinopathy?
OCT: TRIANGLE SHAPED SUBRETINAL FLUID COLLECTION WITH NEUROSENSORY RETINAL DETACHMENT
FA: PROGRESSIVE LEAKAGE WITH ‘INKBLOT’ OR ‘SMOKESTACK’ APPEARANCE
What is the management used for central serous chorioretinopathy?
OBSERVE (SPNTANEOUS RESOLUTION) WITH MANAGEMENT OF RISK FACTORS
CONSIDER PHOTODYNAMIC THERAPY (VERTEPORFIN) WHEN THERE IS AISGNIFICANT VISUAL DISTURBANCE OR CHRONIC CSCR
What is Eales Disease?
IDIOPATHIC PERIPHERAL RETINAL PERIPHLEBITIS THAT TYPICALLY OCCURS IN YOUNG INDIAN MALES
How does Eales Disease present?
USUALLY WITH RECURRENT VITREOUS HAEMORRHAGES
What is a risk factor for Eales Disease?
TUBERCULAR PROTEIN EXPOSURE (TUBERCULIN SENSITIVITY) MAY BE A RISK FACTOR FOR DEVELOPING THIS DISEASE
What is Best Disease?
BEST VITELLIFORM MACULAR DYSTROPHY IS AN AD DEGENERATION OF THE MACULA
What is Best Disease associated with?
LIPOFUSCIN ACCUMULATION IN THE RPE AND ATROPHY OF THE PHOTORECEPTOR LAYER OF THE RETINA
What are the features of Best Disease
BILATERAL CONDITION ASSOCIATED WITH HYPERMETROPIC PATIENTS
EGG YOLK LESION IN MACULA: YELLOW-ORANGE ELEVATED LESION
ELECTRORETINOGRAM (ERG): NORMAL
ELECTRO-OCULOGRAM (EOG): ABNORMAL
CAN BE COMPLICATED BY CNV WHICH LEADS TO DVA
What is stargardt disease?
AN AR CONDITION ASSOCAITED WITH A MUTATION IN THE ABCA4 GENE ON CHROMOSOME 1 THAT CAUSES MACULAR DEGENERATION
How does stargardt disease present?
PRESENTS WITH READING DIFFICULTIES IN PATIENTS UNDER 20
What are the features of stargardt disease?
NORMAL-APPEARING FUNDUS IN EARLY STAGES OF THE DISEASE
LATE FUNDAL APPEARANCE
- BEATEN BRONZE APPEARANCE OF THE MACULA THAT CAN PROGRESS TO GEOGRAPHIC ATROPHY WITH A BULL’S EYE PATTERN
- YELLOW WHITE FLECKS IN RPE
FA: DARK CHOROID (REDUCED CHOROIDAL CIRCULATION)
What is lebers congenital amaurosis?
A RECESSIVE CONDITION THAT PRESENTS WITH SEVERE VISUAL LOSS AT BIRTH, NYSTAGMUS AND ABSENT PUPILLARY REFLEXES
Describe the fundoscopy findings in lebers congenital amauruosis?
EARLY DISEASE; NORMAL
LATE DISEASE: SALT AND PEPPER RETINOPATHY AND BULL’S-EYE MACULOPATHY
What is albinism?
HEREDITARY GROUP OF DISEASES THAT AFFECTS A MELANIN SYNTHESIS O THE EYE ONLY (OCULAR LABINISM – XL INHERITENCE) OR, MORE COMMONLY, THE EYE, SKIN AND HAIR (OCULOCUTANEOUS ALBINISM – AR INHERITENCE)
What are the features of albinism?
SYMPTOMS: dVA DUE TO FOVEAL HYPOPLASIA
SIGNS: NYSTAGMUS, STRABISMUS AND IRIS / FUNDAL HYPOPIGMENTATION RESULTING IN A ‘PINK EYE’ APPEARANCE
OPTIC CHIASM CONTAINS MORE CROSSED FIBRES THAN NORMAL
What is retinitis pigmentosa?
A CONDITION THAT IS CHARACTERISED BY PHOTORECEPTOR DYSFUNCTION (RODS THEN CONES) AND PROGRESSIVE ATROPHY DEGENERATION OF RETINAL TISSUE
What is retinitis pigmentosa caused by?
MOST COMMONLY DUE TO A MUTATION IN THE RHODOPSIN GENE IN THE LONG ARM OF CHROMOSOME 3
INHERITENCE CAN BE AD (MOST COMMON BUT LEAST SEVERE) AR OR XL INHERITENCE (WORST PROGNOSIS)
What are the features of retinitis pigmentosa?
SYMPTOMS: NYCTALOPIA (LIGHT BLINDNESS) AND PERIPHERAL CISION LOSS (TUNNEL VISION IN LATE DISEASE)
TRIAD: PALE OPTIC DISC (WAXY DISC) + BOHNY SPICULES + ARTERIOLAR ATTENUATION
ERG (CONFIRMS DIAGNOSIS AND MONITORS DISEASE PROGRESSION) AND EOG ARE ABNORMAL
What are the associations with retinitis pigmentosa?
OPTIC DISC DRUSEN, MYOPIA, POSTERIOR SUBSCAPULAR CATARACT, CMO, OPEN ANGLE GLAUCOMA KERATOCONUS
What are retinitis-pigmentosa like conditions?
A GROUPS OF AR CONDITIONS CHARACTERISED BY PHOTORECEPTORS DYSFUNCTION WITH SIMILAR FEATURES TO RP
How do retinitis pigmentosa like conditions present?
ALL PRESENT WITH NYCTALOPIA AND TUNNEL VISION WITH ASSOCIATED EXTRAOCULAR FEATURES
What is Usher Syndrome?
MOST COMMON INHERITED CAUSE OF COMBINED DEAFNESS (SENSORINEURAL) + BLIDNESS
What is Refsum Syndrome?
ACCUMULATION OF PHYTANIC ACID
ASSOCIATED ANOSMIA, PERIPHERAL NEUROPATHY AND ICHTHYOSIS
What is bardet-biedel syndrome?
RP-LIKE RETINOPATHY OR BULL’S EYE MACULOPATHY (CONE-ROD DYSTROPHY MORE COMMON)
ASSOCIAED LEARNING DISABILITY, POLYDACTYLY AND OBESTIY
What is Bassen Kornzweig syndrome?
ABNORMAL ABSORPTION OF FAT-SOLUBLE VITAMINS
ASSOCIATED SPINOCEREBELLAR ATAXIA AND ACANTHOCYTOSIS
What are some causes of leukocoria?
CONGENITAL CATARACT
RETINOBLASTOMA
PERSISTENT FETAL VASCULATURE
RETINOPATHY OF PREMATURITY
COATS DISEASE
TOXOCARIASIS
(white pupil / absence of red reflex)
What is a retinoblastoma?
MOST COMMON PRIMARY INTRAOCULAR MALIGNANCY IN CHILDREN
What is a retinoblastoma?
MOST COMMON PRIMARY INTRAOCULAR MALIGNANCY IN CHILDREN
What does retinoblastoma originate from?
ARISES FROM EMBRYONAL PHOTORECEPTOR CELLS OF THE RETINA WITH A MUTATION IN THE TUMOUR SUPPRESSION GENE RB1 ON THE LONG ARM OF CHROMOSOME 13
MOST COMMONLY SPORADIC IN INHERITENCE BUT CAN BE AD
Describe the histopathology of retinoblastoma
FLEXNER ROSETTES ARE CLASSIC BUT HOMER-WRIGHT ROSETTES ARE FLURETTES MAY EXIST
Describe the features of retinoblastoma
AVERAGE AGE OF DIAGNOSIS IS 3 YEARS, PARENTS OFTEN NOTICE LOSS OF RED REFLEX IN PHOTOS
Describe the diagnostic features of retinoblastoma
UNILATERAL (SOMETIMES BILATERAL) LEUKOCORIA + STRABISMUS +/- RED EYE AND dVA
FUNDUSCOPY: WHITE ROUND MASS WITH EITHER ENDOPHYTIC (TOWARDS VITREOUS) OR EXOPHYTIC GROWTH (TOWARDS RPE / CHOROID)
ULTRASOUND SCAN: CAN SHOW CALCIFICATION WITH HIGHER INTERNAL REFLECTIVITY AND CAN HELP DETERMINE TUMOUR THICKNESS
What is persistent fetal vasculature?
ALSO KNOWN AS PERSISTENT HYPERPLASTIC PRIMARY VITREOUS AND IS THE FAILURE OF THE FETAL HYALOID VASCULATURE TO REGERSS
CONDITION IS ASSOCIATED WITH PREMATURITY AND DEVELOPMENT OF CATARACT AND RETINAL DETACHMENT
PATIENTS PRESENT WITHIN THE 2 WEEKS OF LIFE WITH UNILATERAL LEUKOCORIA, MICRO-OPTHALMIA AND CATARACT (MITTENDORF DOT)
What is retinopathy of prematurity?
BLOOD VESSELS GROW FROM THE OPTIC DISC TOWARDS THE PERIPHERY OF THE RETINA IN UTERO AND THIS GROWTH IS DRIVEN THROUGH A RELATIVE HYPOXIC STATE
MAIN RISK FACTOR FOR DEVELOPMENT OF ROP IS BRING BORN PREMATURELY
Why is the periphery the most affected area in Retinopathy of prematurity?
RETINAL VESSELS REACH THE NASAL ORA SERRATA (JUNCTION BETWEEN RETINA AND PARS PLANA) AT 32 WEEKS GESTATION AND THE TEMPORAL AT 40 WEEKS
What are the risk factors for retinopathy if prematurity?
PREAMTURELY BORN INFANT (< 32 WEEKS GESTATION)
WEIGHT LESS THAN 1500G
EXTENDED OXYGEN TREATMENT: FOR EXAMPLE IN NEONATAL RESPIRATORY DITRESS SYNDROME
Describe the locations of retinopathy of prematurity
ZONE I: A CIRCLE WITH RADIUS OF TWICE THE DISTANCE FROM THE DISC TO FOVEA WITH THE OPTIC DISC BEING THE CENTRE
ZONE II: EDGE OF ZONE I TO NASAL ORA SERRATA
ZONE III: FROM ZONE II TO THE REMAINING RETINA
Describe the stages of retinopathy of prematurity
WHITE DEMARCATION LINE SEPARATING VASCULAR FROM AVASCULAR AREAS
RIDGE: ELEVATED AND THICKENED DEMARCATION LINE
EXTRARETINAL FIBROVASCULAR PROLIFERATION OR NEOVASCULARISATION INFILTRATING THE VITREOUS
PARTIAL RETINAL DETACHMENT (A – EXTRAFOVEAL; B – FOVAL)
TOTAL RETINAL DETACHMENT (MOST COMMONLY TRACTIONAL)
What is plus disease?
retinopathy of prematurity ADDITIONAL SIGNS OF INCREASED VENOUS DILATATION AND/OR ARTERIOLAR TORTUOSITY OF THE POSTERIOR RETINAL VESSELS CAN INCREASE THE SEVERITY OF THE CONDITION
How is retinopathy of prematuriy screened for?
HIGH RISK CHILDREN SHOULD BE SCREENED VIA AN INDIRECT OPHTHALMOSCOPE WITH 28D LENS, COMPLICATIONS AND PERMANENT VISUAL LOSS CAN OCCUR IF THE DISEASE IS NOT TREATED EARLY
UK ROP SCREENING RECOMMENDATIONS (11) INCLUDE
ALL INFANTS BORN AT LESS THAN 32 WEEKS GESTATION AND / OR WEIGHING LESS THAN 1501G SHOULD BE SCREENED
- IF BORN < 27 WEEKS GESTATION, SCREEN AT 30-31 WEEKS POSTMENSTRUAL AGE
- IF BORN > 27 WEEKS AND < 32 WEEKS GESTATION OR BORN > 32 WEEKS GESTATIONAL AGE BUT WEIGH < 1501 G, SCREEN AFTER 4-5 WEEKS POSTNATAL AGE
- SCREEN WEEKLY IF STAGE 3 DISEASE PLUS DISEASE OR IF VESSELS END AT ZONE 1 OR POSTERIOR ZONE 2
- OTHERWISE SCREEN EVERY 2 WEEKS
Describe the management of prematurity of retinopathy
TREATMENT WITHIN 48 HOURS WITH TRANSPUPILLARY DIODE LASER
TREAT IF:
- ZONE 1, ANY STAGE PLUS DISEASE
- ZONE 2: STAGE 3 PLUS DISEASE
- ZONE 1: STAGE WITHOUT PLUS DISEASE
What is coats disease?
UNILATERAL CONDITION OF UNKNOWN AETIOLOGY THAT IS CHARACTERISED BY THE TELANGIECTASIA AND NEOVASCULARISATION
COMMONNLY AFFECTS YOUNG BOYS
What are the features of coats disease?
DVA, STRABISMUS AND LEUKOCORIA
RETINAL TELANGIECTASIA AND MICROANEURYSMS
INTRA/SUBRETINAL EXUDATION
COMPLICATIONS: EXUDATIVE RETINAL DETACHMENT AND NVG
What is von-Hippel-Lindau disease?
AD CONDITION AFFECTING THE VHL GENE ON THE SHORT ARM OF CHROMOSOME 3
THIS CONDITION AFFECTS MULTIPLE ORGANS INCLUDING THE BRAIN, SPINAL CORD, RETINA, KIDNEYS, ADRENAL GLANDS AND PANCREAS
What are the features of von hippel lindau disease?
RETINAL CAPILLARY HAEMANGIOMA WITH TORTUOUS FEEDER VESSELS
RENAL CELL CARCINOMA
PHAEOCHROMOCYTOMA
CNA HAEMANGIOBLASTOMA
What is choroidal melanoma?
UVEAL TRACT MALIGNANT MELANOMAS ARISE FROM MELANOCYTES IN EITHER THE IRIS, CILIARY BODY OR CHOROID
CHOROIDAL MELANOMA IS THE MOST COMMON
Describe a choroidal melanoma
USUALLY UNILATERAL IN PRESENTATION
CAN BE ASYMPTOMATIC OR CAUSE dVA AND EXUDAIVE RETINAL DETACHMENT
THEY CAN APPEAR PIGMENTED WITH A ‘COLLAR-STUD’ CONFIGURATION IF BRUCH’S MEMBRANE IS RUPTURED
METASTATIC SPREAD IF USUALLY TO THE LIVER
CHROMOSOME 3 MONOSOMY IS AN INDICATORY OF POOR PROGNOSIS
Describe the management of central retinal vein occlusion
NON-ISCHAEMIC
- IF VA IS 6/96 OR BETTER AND THERE IS EVIDENCE OF MACULAR OEDEMA ON OCT
- COMMENCE INTRAVITREAL ANTI-VEGF OR OZURDEX (DEXAMETHASON) IMPLANT
- BOTH TREATMENTS ARE FIRST LINE, ALTHOUGH YOUNGER PHAKIC PATIENTS OR WITH HISTORY OF GLAUCOMA SHOULD BE STARTED ON ANTI-VEGF
- PATIENTS WITH HIGH CARDIOVASCULAR PROFILE SHOULD BE STARTED ON OZURDEX IMPLANT
ISCHAEMIC
- NO NEOVASCULARISATION AND OPEN ANGLE: MONITOR FOR NEOVASCULARISATION AND GLAUCOMA
- NEOVASCULARISATION PRESENT: URGENT PRP +/- CYCLODIODE LASER THERAPY IF ANGLE CLOSURE
