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Excerpts from the job aid with illustrations for the zones, stages and types of ROP
Excerpts from the job aid

A practical tool for ROP screening

In this step, we share a practical tool, the ‘ROP classification and decision making’ job aid. This downloadable infographic summarises what we have learned this week about the classification of ROP and is designed to be used to support decision making and communications during ROP screening. This tool can be used to explain to parents what is happens at the back of the eye in ROP and also how ROP progresses.

Download the job aid (PDF)

How to use the job aid

Use the job aid as a guide when noting your observations and making appropriate management decisions:

  1. Which areas of the retina are affected? Use the Zones illustration

  2. What are the key features? Use the Stages, Plus disease and Aggressive posterior ROP illustrations

  3. Based on your answers to questions 1 and 2: What type of ROP do you see? What is the management decision? Use the illustrations for the Types of ROP illustrations

You may also find the job aid helpful to support discussions with colleagues, parents and carers.

In week 3 we will add more detail into the job aid on schedules for treatment and follow up.

Job aid: ROP classification and decision making


Zones of ROP

Illustration indicating the zones of ROP for the left and right eyes. Zone 1 is a central circle over the macula & optic disk, zone 2 is a ring around zone 1 extending to the ora serrata at the nasal side & zone 3 is a ring around zone 2 extending to the ora serrata
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Stages of ROP

Illustration of the 5 stages of ROP as seen in the retina and described below

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  • Stage 1: Demarcation line between vascular and avascular retina
  • Stage 2: Raised ridge
  • Stage 3: Vascularised ridge
  • Stage 4: Subtotal retinal detachment: 4a) Macular not detached or 4b) Macular detached (as shown)
  • Stage 5: Detached retina: Total retinal detachment: 5a) Open funnel or 5b) Closed funnel (as shown)

Plus disease

Illustration of the signs of plus disease in ROP as seen in the retina and described below
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Signs of ‘plus’ disease:

  • Retinal vessels dilated and tortuous in all four quadrants
  • Iris vascular engorgement (dilated)
  • Poor pupillary dilatation
  • Vitreous haze.

Signs of ‘pre-plus’ disease:

  • Vessels dilated and more tortuous than normal.

Aggressive posterior ROP

Illustration of the signs of aggressive posterior ROP as seen in the retina and described below
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  • Prominent plus disease
  • Ill-defined demarcation line
  • Flat network of proliferating new vessels
  • Difficult to differentiate between arterioles and venules
  • Progression is not through classic stages 1 to 3.

Types of ROP to support management decisions

Type 1 ROP: High risk - treatment required within 24 - 48 hours

Zone I, stage 3 without plus disease

Illustration of retinal image showing Zone 1 Stage 3 ROP without plus disease
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Zone I, any stage with plus disease

Illustration of retinal image showing Zone I, any stage ROP with plus disease
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Zones I & II, stages 2 & 3 with plus disease

Illustration of retinal image showing Zones I & II, stages 2 & 3 ROP with plus disease.
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Type 2 ROP: Low risk - follow up screening required

Zone 1 Stage 1 or 2 without plus disease

Retinal illustration showing the main features of Zone I, stage 1 or 2 without plus disease ROP
Click to expand

Zone 2 Stage 3 without plus disease

Retinal illustration showing the main features ofZone 2 Stage 3
without plus disease ROP
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This article is from the free online course:

Retinopathy of Prematurity: Practical Approaches to Prevent Blindness

London School of Hygiene & Tropical Medicine