ophthamology revision

Using the direct ophthalmoscope…

You will find a word at each of the points indicated by the boxes…

A patient standing six metres from a standard Snellen Chart can only see the top line. How is this recorded in snellen notation?

E5 minutes of arc: 6/6 acuity

10 minutes: 6/12

20 minutes: 6/24

30 minutes: 6/36

6 metres

E50 minutes of arc: 6/60 acuity

The human eye is just able to discern separate objects if the angle between them is 30 seconds of arc.

6

12

The test distance

An average eye would see this line at 12 metres

Identify these refractive errors

Myopia

“Short sighted”

Hypermetropia

“long sighted”

What abnormality does this photo show, and what is the surgical procedure called which corrects it?

What is this abnormality called, and what is the main symptom it causes?

What stain has been used, and what abnormality is shown?

What abnormality is shown here?

Suggest two important differential diagnoses

Suggest two useful investigations

This patient suddenly lost all useful vision in her right eye a few hours before the photo was taken.

What is the diagnosis?

What tests would you perform

What is the commonest accompanying systemic disease?

What pupil abnormality would be present?

Name three abnormalities shown here

Give the diagnosis

Suggest a cause

Extra-ocular muscles

Medial Rectus Third nerve

Sixth nerve

Third nerve

Third nerve

Fourth nerve

Third nerve

Lateral rectus

Superior RectusInferior rectus

Superior Oblique

Inferior Oblique

Muscle: Nerve supply:

3

5

9

2

8

Humphrey Visual Field Analyser

Identify two abnormalities, and suggest a diagnosis

What is the diagnosis here?

What’s the diagnosis here?

What is the main abnormality shown here?

And here?

Which is the abnormal eye, and what word is used to describe the visual acuity deficit?

Before After

Diagnosis?

What is this condition called?

What’s the link..?

Different patients, same underlying diagnosis…

Laser treatment

Answers

• Slide 2 - 6/60• Slide 5 – Myopia “Short sighted” (top pic)

and hypermetropia “long sighted” (bottom pic)

• Slide 6 - Cataract – phaco-emulsification• Slide 8 - Entropion, where eye lash folds in

towards eye. Main symptom: gritty scratchy “there’s something in my eye” kind of pain

Answers

• Slide 9 - Fluoracin stain showing up corneal ulcer

• Slide 10 - Abnormality: swollen, blurry optic disc edge (papilloedema). Differentials: Raised intracranial pressure, malignant hypertension, idiopathic intracranial hypertension. Investigations – blood pressure, CT scan

Answers• Slide 11 - Painless sudden loss of vision =

central retinal artery occlusion/thrombosis. Tests – BP, cholesterol, glucose. Patient would be a vascularpath. Pupil abnormality is relative afferent pupillary defect, as retina not able to detect light

• Slide 13 – Complete ptosis, “down & out” eye, dilated pupil = 3rd nerve palsy. Possible cause = posterior communicating artery aneurysm pressing on nerve, or vascualr occlusion along the length of the 3rd nerve.

Answers• Slide 15

– 2 – right eye loss of vision– 3 – bitemporal hemianopia “tunnel vision”– 5 – right homonymous hemianopia– 8 – right homonymous hemianopia– 9 – right homonymous hemianopia with central

sparing• Slide 17 – Horners, see partial ptosis,

constricted pupil & decreased sweating. Causes anything along the length of the sympathetic chain, e.g. tumour, vascular origin

Answers

• Slide 18 – anterior uveitis, aka iritis• Slide 19 – glaucoma (see cupping of optic

disc and increased intraocular pressure)• Slide 20 – leukochoria (white reflex/white

pupil). Causes = retinoblastoma, cataract• Slide 21 – strabismus (“squint”)• Slide 22 – left eye abnormal. Amblyopia• Slide 23 - hypothryroidism

Answers

• Slide 24 – central retinal vein occlusion, see multiple haemorrhages

• Slide 25 – internal carotid artery atheroma and consequent embolus seen on retina

• Slide 26 – diagnosis = diabetic retinopathy• Slide 28 – Stevens Johnson with

decreased tear production & scarring

Answers

• Slide 29 – areas of depigmentation of retina

• Slide 30 – RA and see deterioration of the sclera called scleromalacia perforans

• Slide 31 – sturge weber syndrome• Slide 32 – inverting eye lid with cotton bud