Competency 6.1.1 Flashcards
Glaucoma Definition
A series of conditions which are characterised by progressive damage to optic nerve head and retinal nerve fibre layer
Types of Glaucoma Covered Here
- POAG
- NTG
- ACG
- Secondary Glaucoma
- PDS
- Pseudoexfoliation
- Neovascular
- Inflammatory
POAG Risk Factors
IOP
- Higher IOP is greater risk
- Asymmetry of 4mmHg or more is significant
- Pressures over 25mmHg very significant with increased risk over 21mmHg
Age
- More common in older individuals
Over 40 years for African heritage and over 65 for caucasians
Ethnicity
- 5x more prevalent in africans due to thinner corneas
- Develops at earlier age and often harder to control
Family History
- 9.2x higher chance of developing POAG if first degree relative affected
Myopia
- 3.00DS or more
- Increased susceptibility to damage due to stretching of fibres
- Large AC makes POAG more likely than other forms of glaucoma
Optic Nerve Structure
- Larger disc more susceptible
Vascular Diseases
- HBP and DM increase susceptibility
Others
- Anti-VEGF (Especially Bevacizumab)
- Long term use of contraceptive pill
NTG Risk Factors
Age
- Tend to be older than those with POAG
Ethnicity
- More often in Japanese populations
CCT
- Is lower than in POAG patients
Abnormal Vasoregulation
- Migrain sufferers
- Reynauds phenomenon
- Systemic hypotension
Gender
- More common in females
Family History
- Can have cross links between POAG and NTG
ACG Risk Factors
Age
- Average age of 62 year for pupillary block mechanism
- Younger for non-pupillary block
Gender
- More common in females
Race
- More common in east asians
- Non-pupillary block more common in these populations
Family History
- Important but poorly defined relationship
Refraction
- Hyperopic due to short AL
Pigmentary Glaucoma Risk Factors
Young, white myopic men
Pseudoexfoliative Glaucoma Risk Factors
- Rare prior to 5th decade, prevalence increases rapidly after 6th decade
- Highest prevalence is in Scandinavia
Neovascular Glaucoma Risk Factors
- Ischaemic CRVO
- Diabetes
- CRAO (less common)
- Tumours
Inflammatory Glaucoma
- AC activity
- Steroid use
Cataract Risk Factors
Age
- Prevalence increases with age, most commonly affects over 70s
Gender
- More common in females as they tend to live longer
UV Exposure
- UVA and UVB both contribute to the formation of cataract
- High UV environments include places such as Bolivia and working outside all the time
Smoking
- Alters lens cells through oxidation
Diabetes
- Increased blood sugar causes lens to swell
- Excess glucose then converted into sorbitol which results in opacity
Trauma
- Blunt trauma causing flower shaped cataract
- Electric shock causing snowflake shaped opacity
Medicines
- Use of corticosteroids causes PSC
DR Risk Factors
Duration of Diabetes
- Most important risk factor
- In diabetics diagnosed before 30, indigence of DR is 50% after 10 years and 90% after 30 years
- Stronger predictor of proliferative disease than maculopathy
Control
- Good control can delay or prevent onset of DR
- Type 1 patients may benefit more than type 2
- Sudden control improvement may be associated with short term DR progression
Pregnancy
- Sometimes associated with rapid DR progression
- Related to pre-pregnancy DR severity
- Diabetic macular oedema resolves spontaneously after pregnancy in many cases
Hypertension
- Tight control can be of benefit especially in those with maculopathy
Nephropathy
- Kidney problems lead to worsening of DR
- Treatment of renal disease can lead to better treatment outcome with photocoagulation laser
Macular Degeneration Risk Factors
Age
- Major risk factor
- Eyes remove ability to remove toxins with age
Race
- More common in white individuals than in other races
- Lack of pigmentation results in inability to remove debris
Family History
- Upto 3x greater risk if first degree relative has disease
- More than 50 genes implicated in AMD developement
Gender
- Female gender suspected
Smoking
- Roughly doubles risk of AMD
Sunlight
- Blue light damages retinal cells resulting in debris buildup
Diet
- High fat diet
- Antioxidants and leafy green veg thought to be protective
