Clinical Skills 5 - E - Opthalmoscopy (fundoscopy), Retinitis of prematurity

Question 1

To begin with in a fundoscopy exam, what is fundoscopy?

Answer 1

Examination of the fundus (retina) of the eye using an othalmoscope

Question 2

Like every exam, how to you start of a fundoscopy examintion?

Answer 2

Begin examination by introducing yourself to the patient and clarifying name and date of birth Then explain the procedure

Question 3

When carrying out othalmoscopy, what do you tell the patient to do whilst you begin the first inspecting of the eye?

Answer 3

Ask the patient to look at an focus on an object in the distance Also first thing you look for is the red light reflex

Question 4

What is the red light reflex?

Answer 4

The red reflex is the reflection on the retina which is a reddish colour - the light should appear red which means all objects in front of the light are transparent as they should be

Question 5

In a patient if there is no red reflex or it is weak, what can this be indicative off?

Answer 5

This can be indicative off a cataracts as this causes a cloudy lens making it harder for the light to pass

Question 6

If there are black marks on a patient who has had cataracts when looking for the red reflex, what is this?

Answer 6

Cararact treatment usually shows up as black on the red reflex

Question 7

What setting is the othalmoscope on when looking for the red reflex? What do you do after the red reflex? what are you looking at now?

Answer 7

Othalmoscope is on 0 After the red reflex, move closer and examine the patients external eye features - ie eyelids, lashes, pupil and iris and cornea, and sclera Opthalmoscope is now on 10

Question 8

After examining the features of the eye, move closer and examine the fundus of the eye What side is the optic disc? What setting is the opthalmoscope on?

Answer 8

The opthalmoscope is now on 0 The optic disc is on the nasal retina

Question 9

What are the 3 things to look for when examining the optic disc?

Answer 9

Look for Contour - well or ill defined disc margin Cup - the cup is the central part of the optic disc, this is where there are no nerve fibres Colour - optic disc should be a pinky colour

Question 10

What is said when describing the cup?

Answer 10

use the cup to disc ratio A normal cup to disc ratio is 0.2 to 0.6

Question 11

How is the cup to disc ratio measured? What disease causes a progressive increase in cup to disc ratio?

Answer 11

Cup to disc ratio is measured using what percentage of the vertical height of the optic disc that the vertical height of the optic cup takes up Glaucoma cause an increase in size of optic cup as the increased IOP damages nerve fibres

Question 12

What is the rule when examinign the space between the optic disc and cup?

Answer 12

This is the ISNT rule Space size is biggest Inferiorly Superiorly Nasally And finally temporally (on the side of the macula)

Question 13

What is retinitis of prematurity?

Who does it affect?

Answer 13

Retinopathy of prematurity (ROP) is an eye disease that can happen in premature babies.

It causes abnormal blood vessels to grow in the retina, and can lead to blindness.

Question 14

During development, blood vessels grow from the central part of the retina outwards. This process is completed a few weeks before the normal time of delivery. However, in premature babies it is incomplete. If blood vessels grow normally, ROP does not occur.

How does abnormal vessel development potentially lead to blindless in the infant?

Answer 14

If the vessels grow and branch abnormally the baby develops ROP. These abnormal blood vessels may grow up from the plane of the retina and may bleed inside the eye- known as fibrovascular proliferation

When the blood and abnormal vessels are reabsorbed, it may give rise to multiple band like membranes which can pull up the retina, causing detachment of the retina and eventually blindness before 6 months - it is the fibrous scar tissue that can cause detachment of the retina

Question 15

What are various risk factors associated with the development of retinitis of prematurity?

Answer 15

Various risk factors contribute to the development of ROP. They are:

• Prematurity
• High exposure to oxygen
• Low birth weight
• Various types of infections
• Cardiac defects

Question 16

Why can high levels of oxygen given to premature babies cause retinitis of prematuirty?

Answer 16

The normal growth of the blood vessels is directed to relatively low-oxygen areas of the retina, but the vessels remain in the plane of the retina and do not grow into the vitreous humor.

If excess oxygen is given, normal blood vessels degrade and cease to develop. When the excess oxygen environment is removed, the blood vessels rapidly begin forming again and grow into the vitreous humor of the eye from the retina.

Question 17

How is retinitis of prematuirty diagnosed?

Answer 17

ROP has no signs or symptoms when it first develops in a newborn. The only way to detect it is through an eye exam by an ophthalmologist .

Usually screening is carried out in premature babies born before 31 weeks

Can see the detahced retina on the image

Question 18

How is retinitis of prematuirty treated?

Answer 18

• Some cases of ROP are mild and correct themselves. But others progress to scarring, pulling the retina away from the rest of the eye. These cases need surgery to prevent vision loss or blindness.
• ROP surgery stops the growth of abnormal blood vessels. Treatment focuses on the peripheral retina (the sides of the retina) to preserve the central retina (the most important part of the retina). ROP surgery involves scarring areas on the peripheral retina to stop the abnormal growth and eliminate pulling on the retina.

Peripheral retinal ablation is the mainstay of ROP treatment.

Question 19

What can the peripheral retinal ablation mean for the patients vision?

Answer 19

Because surgery focuses on the peripheral retina, some amount of peripheral vision may be lost. However, by preserving the central retina, the eye can still do vital functions like seeing straight ahead, distinguishing colors, reading, etc

Question 20

What is the treatment for retinitis of prematuirty that may be carried out after retinal detachment has taken place?

Answer 20

For advanced cases of ROP with retinal detachment, these methods are used:

• Scleral buckling: - This involves placing a flexible band, usually made of silicone, around the circumference of the eye. The band goes around the sclera causing it to push in, or “buckle.” This, in turn, pushes the torn retina closer to the outer wall of the eye. This surgery takes 1–2 hours.
• Vitrectomy - This complex surgery involves replacing the vitreous (the clear gel in the center of the eye) with a saline (salt) solution. This allows for the removal of scar tissue and eases tugging on the retina, which stops it from pulling away. Vitrectomy can take several hours.