Medical Ophthamology Flashcards
What is Diabetes Mellitus (DM) associated with in terms of ocular damage?
Diabetes Mellitus (DM) causes long-term damage to ocular structures, potentially leading to blindness.
Which types of diabetes mellitus exist and how do they differ in prevalence?
Type I accounts for 5-10% (autoimmune), and Type 2 for 90-95% (develops later in life).
What is a stye, and how is it treated?
A stye is a small abscess caused by acute staphylococcal infection; treated with hot compresses, antibiotics, and incision and drainage.
How does blepharitis present in patients with diabetes?
Blepharitis manifests as chronic staphylococcal infection of the lid margin, treated with lid hygiene and systemic tetracycline.
What causes chalazion, and what type of lesion is it?
Chalazion is a chronic, sterile granulomatous lesion caused by retained sebaceous secretions.
Why are cataracts more common in patients with diabetes?
Cataracts are more frequent due to metabolic abnormalities in diabetes.
What are the characteristic features of diabetic cataracts?
Diabetic cataracts often present with anterior cortical spokes or posterior subcapsular plaques.
What is the second leading cause of neovascular glaucoma?
Neovascular glaucoma develops due to angle closure from fibrovascular tissue.
What is rubeosis iridis and how is it related to DM?
Rubeosis iridis refers to abnormal blood vessel growth on the iris in diabetes.
What is diabetic retinopathy (DR), and why is it a significant cause of blindness?
Diabetic retinopathy is a leading cause of blindness due to microangiopathy affecting the retina.
What are the major risk factors for developing diabetic retinopathy?
Risk factors include poor glucose control, long duration of DM, hypertension, nephropathy, pregnancy, and anaemia.
Describe the pathogenesis of diabetic retinopathy.
Diabetic retinopathy results from capillary occlusion, leakage, and blood abnormalities.
What are the early-stage symptoms of diabetic retinopathy?
Early-stage diabetic retinopathy has no symptoms or presents with blurry vision.
Why is regular eye examination crucial for diabetics?
Regular eye exams are essential since early diabetic retinopathy is asymptomatic but treatable.
List the key signs of diabetic retinopathy.
Signs include hard exudates, cotton wool spots, retinal haemorrhages, and neovascularisation.
What is the significance of microaneurysms in diabetic retinopathy?
Microaneurysms are the earliest signs of diabetic retinopathy.
How do hard exudates manifest in diabetic retinopathy?
Hard exudates result from lipid deposits in the retina due to leakage.
What role do new blood vessels play in diabetic retinopathy?
New blood vessels are fragile and can rupture, causing vitreous haemorrhage.
How does retinal detachment occur in diabetic patients?
Retinal detachment occurs due to traction from new blood vessels.
What is vitreous haemorrhage, and how does it develop in diabetic retinopathy?
Vitreous haemorrhage occurs when neovascular fronds rupture.
Differentiate between non-proliferative and proliferative diabetic retinopathy.
Non-proliferative retinopathy lacks new vessels; proliferative involves neovascularisation.
What is diabetic maculopathy?
Diabetic maculopathy affects the macula, leading to central vision loss.
How is early treatment of diabetic retinopathy classified?
Early treatment includes classifying diabetic retinopathy into stages (mild, moderate, severe).
What management strategies are important in diabetic eye disease?
Management includes glucose control, blood pressure regulation, and laser therapy.
How does laser photocoagulation help in managing diabetic retinopathy?
Laser photocoagulation prevents progression by sealing leaking vessels.
What medications are used in the intravitreal treatment of diabetic retinopathy?
Anti-VEGF medications like bevacizumab reduce neovascularisation.
When is vitrectomy indicated in diabetic retinopathy?
Vitrectomy is required for vitreous haemorrhage or retinal detachment.
How does public health enlightenment contribute to preventing diabetic retinopathy?
Public health efforts aim to increase awareness and screening.
Why is hypertension associated with diabetic retinopathy?
Hypertension exacerbates diabetic retinopathy by damaging blood vessels.
What is hypertensive retinopathy and how does it affect ocular health?
Hypertensive retinopathy involves vascular changes due to sustained elevated blood pressure.
What are the major factors influencing the development of hypertensive retinopathy?
Severity and duration of hypertension influence retinopathy risk.
Explain the pathogenesis of hypertensive retinopathy.
Vasoconstriction and increased permeability cause haemorrhages and exudates in hypertensive retinopathy.
Describe the stages of the Kieth-Wegner classification for hypertensive retinopathy.
The Kieth-Wegner classification outlines four stages of hypertensive retinopathy.
What are the features of Grade 1 hypertensive retinopathy?
Grade 1 presents with mild arteriolar narrowing.
How does Grade 2 hypertensive retinopathy present?
Grade 2 shows more marked arteriolar narrowing and focal attenuation.
What is the Bonnet sign, and in which grade of hypertensive retinopathy does it occur?
Bonnet sign is the tapering of veins near arteriolar crossings in Grade 2 retinopathy.
What are the clinical features of Grade 3 hypertensive retinopathy?
Grade 3 presents with copper wiring, flame-shaped haemorrhages, and cotton wool spots.
Describe the Gunn and Salus signs in hypertensive retinopathy.
Gunn and Salus signs indicate arteriovenous crossing changes in hypertensive retinopathy.
What characterises Grade 4 hypertensive retinopathy?
Grade 4 shows silver wiring and bilateral disc swelling, indicating severe retinopathy.
What are the consequences of malignant hypertension on the eye?
Malignant hypertension can cause severe ocular complications, including optic neuropathy.
How does ocular ischaemic syndrome present in hypertensive patients?
Ocular ischaemic syndrome leads to severe vision loss from restricted blood flow.
What role does laser therapy play in treating hypertensive retinopathy complications?
Laser therapy treats retinal neovascularisation and haemorrhages in hypertensive retinopathy.
How is retinal vascular occlusion managed in hypertensive retinopathy?
Retinal vascular occlusion is managed through blood pressure control and anti-VEGF injections.
What similarities exist between the retinal and cardiovascular systems in hypertension?
Retinal changes mirror systemic cardiovascular issues, aiding in diagnosis.
Why is sickle cell disease significant in the context of eye health?
Sickle cell disease causes significant visual loss due to vascular complications.
What genetic mutation causes sickle cell disease?
A point mutation in the β-globin gene on chromosome 11 causes sickle cell disease.
Describe the haemoglobin structure affected by sickle cell disease.
Haemoglobin S leads to reduced oxygen transport and abnormal red blood cell shapes.
What is the global epidemiology of sickle cell disease?
Sickle cell disease affects over 400,000 children annually, mostly in sub-Saharan Africa.
What percentage of the Nigerian population is affected by sickle cell disease?
In Nigeria, 150,000 children are born annually with HbSS.
How does sickle cell disease affect the eyes?
Sickle cell disease leads to occlusion of small retinal vessels, causing ischaemia.
Describe the pathophysiology of sickle cell retinopathy.
Vascular proliferation in sickle cell disease results in unstable blood vessels that can rupture.
What are the clinical features of sickle cell eye disease?
Early stages cause mild blurry vision, while advanced stages lead to blindness.
What distinguishes non-retinal from retinal lesions in sickle cell disease?
Non-retinal lesions include conjunctival issues, while retinal lesions cause vision loss.
How does vascular proliferation lead to eye damage in sickle cell disease?
Vascular proliferation in sickle cell disease leads to vitreous haemorrhage.
What are the stages of retinal lesions in sickle cell retinopathy?
Retinal lesions are divided into non-proliferative and proliferative stages.
Why is the retina considered an accessible organ for hypertension monitoring?
The retina’s microcirculation makes it a window into hypertension’s effects.
What is the significance of fundoscopic examination in diabetic and hypertensive patients?
Fundoscopy allows visualisation of retinal blood vessels to detect hypertension-related changes.
How does haemoglobin S affect the shape and function of red blood cells?
Sickle haemoglobin causes red blood cells to become rigid and sticky.
What systemic complications arise from sickle-shaped red blood cells?
Sickle-shaped red blood cells can block blood flow, causing pain and organ damage.
How is sickle cell retinopathy managed?
Sickle cell retinopathy is managed through regular eye exams and treatment of neovascularisation.
What is the role of oxygen therapy in managing sickle cell-related eye complications?
Oxygen therapy helps prevent retinal hypoxia in sickle cell patients.
What preventative measures are recommended for diabetic retinopathy?
Diabetic retinopathy can be prevented with regular eye exams and tight glucose control.
What is the relevance of anti-VEGF drugs in diabetic eye disease?
Anti-VEGF drugs reduce new blood vessel growth in diabetic retinopathy.
How can early diagnosis of hypertensive and diabetic retinopathy prevent blindness?
Early diagnosis and treatment prevent blindness in hypertensive and diabetic retinopathy.
What are the systemic implications of untreated retinopathy in hypertensive and diabetic patients?
Untreated retinopathy can cause systemic complications like stroke and heart disease.
