Key priorities for implementation

Key priorities for implementation

Diagnosis

  • At diagnosis offer all people who have COAG, who are suspected of having COAG or who have OHT all of the following tests:

    • intraocular pressure (IOP) measurement using Goldmann applanation tonometry (slit lamp mounted)

    • central corneal thickness (CCT) measurement

    • peripheral anterior chamber configuration and depth assessments using gonioscopy

    • visual field measurement using standard automated perimetry (central thresholding test)

    • optic nerve assessment, with dilatation, using stereoscopic slit lamp biomicroscopy with fundus examination.

  • Ensure that all of the following are made available at each clinical episode to all healthcare professionals involved in a person's care:

    • records of all previous tests and images relevant to COAG and OHT assessment

    • records of past medical history which could affect drug choice

    • current systemic and topical medication

    • glaucoma medication record

    • drug allergies and intolerances.

Monitoring

  • Monitor at regular intervals people with OHT or suspected COAG recommended to receive medication (see 'Treatment for people with OHT or suspected COAG'), according to their risk of conversion to COAG (see table 1).

Table 1 Monitoring intervals for people with OHT or suspected COAG who are recommended to receive medication

Clinical assessment

Monitoring intervals (months)

IOP at target a

Risk of conversion to COAG b

Outcome c

IOP alone d

IOP, optic nerve head and visual field

Yes

Low

No change in treatment plan

Not applicable

12 to 24

Yes

High

No change in treatment plan

Not applicable

6 to 12

No

Low

Review target IOP or change treatment plan

1 to 4

6 to 12

No

High

Review target IOP or change treatment plan

1 to 4

4 to 6

a Person is treated and IOP is at or below target. If IOP cannot be adequately controlled medically, refer to consultant ophthalmologist.

b To be clinically judged in terms of age, IOP, CCT, appearance and size of optic nerve head.

c For change of treatment plan refer to treatment recommendations.

d For people started on treatment for the first time check IOP 1 to 4 months after start of medication.

  • Monitor at regular intervals people with COAG according to their risk of progression to sight loss (see table 2).

Table 2 Monitoring intervals for people with COAG

Clinical assessment

Monitoring intervals (months)

IOP at target a

Progression b

Outcome c

IOP alone d

IOP, optic nerve head and visual field

Yes

Noe

No change in treatment plan

Not applicable

6 to 12

Yes

Yes

Review target IOP and change treatment plan

1 to 4

2 to 6

Yes

Uncertain

No change in treatment plan

Not applicable

2 to 6

No

Noe

Review target IOP or change treatment plan

1 to 4

6 to 12

No

Yes/uncertain

Change treatment plan

1 to 2

2 to 6

a IOP at or below target.

b Progression = increased optic nerve damage and/or visual field change confirmed by repeated test where clinically appropriate.

c For change of treatment plan refer to treatment recommendations.

d For people started on treatment for the first time check IOP 1 to 4 months after start of medication.

e No = not detected or not assessed if IOP check only following treatment change.

Treatment for people with OHT or suspected COAG

  • Offer people with OHT or suspected COAG with high IOP treatment based on estimated risk of conversion to COAG using IOP, CCT and age (see table 3).

Table 3 Treatment for people with OHT or suspected COAG

CCT

More than
590 micrometres

555–590 micrometres

Less than
555 micrometres

Any

Untreated

IOP (mmHg)

> 21 to 25

> 25 to 32

> 21 to 25

> 25 to 32

> 21 to 25

> 25 to 32

> 32

Age (years)a

Any

Any

Any

Treat until 60

Treat until 65

Treat until 80

Any

Treatment

No treat-ment

No treat-ment

No treat-ment

BBb

PGA

PGA

PGA

a Treatment should not be routinely offered to people over the age threshold unless there are likely to be benefits from the treatment over an appropriate timescale. Once a person being treated for OHT reaches the age threshold for stopping treatment but has not developed COAG, healthcare professionals should discuss the option of stopping treatment.

The use of age thresholds is considered appropriate only where vision is currently normal (OHT with or without suspicion of COAG) and the treatment is purely preventative. Under such circumstances the threat to a person's sighted lifetime is considered negligible. In the event of COAG developing in such a person then treatment is recommended.

b If beta-blockers (BB) are contraindicated offer a prostaglandin analogue (PGA).

Treatment for people with COAG

  • Offer people newly diagnosed with early or moderate COAG, and at risk of significant visual loss in their lifetime, treatment with a prostaglandin analogue.

  • Offer surgery with pharmacological augmentation (mitomycin C [MMC] or 5-fluorouracil [5-FU])[1] as indicated to people with COAG who are at risk of progressing to sight loss despite treatment. Offer them information on the risks and benefits associated with surgery.

Organisation of care

  • Refer people with suspected optic nerve damage or repeatable visual field defect, or both, to a consultant ophthalmologist for consideration of a definitive diagnosis and formulation of a management plan.

  • People with a diagnosis of OHT, suspected COAG or COAG should be monitored and treated by a trained healthcare professional who has all of the following:

    • a specialist qualification (when not working under the supervision of a consultant ophthalmologist)

    • relevant experience

    • ability to detect a change in clinical status.

Provision of information

  • Offer people the opportunity to discuss their diagnosis, prognosis and treatment, and provide them with relevant information in an accessible format at initial and subsequent visits. This may include information on the following:

    • their specific condition (OHT, suspected COAG and COAG), its life-long implications and their prognosis for retention of sight

    • that COAG in the early stages and OHT and suspected COAG are symptomless

    • that most people treated for COAG will not go blind

    • that once lost, sight cannot be recovered

    • that glaucoma can run in families and that family members may wish to be tested for the disease

    • the importance of the person's role in their own treatment – for example, the ongoing regular application of eye drops to preserve sight

    • the different types of treatment options, including mode of action, frequency and severity of side effects, and risks and benefits of treatment, so that people are able to be active in the decision-making process

    • how to apply eye drops, including technique (punctal occlusion and devices) and hygiene (storage)

    • the need for regular monitoring as specified by the healthcare professional

    • methods of investigation during assessment

    • how long each appointment is likely to take and whether the person will need any help to attend (or example, driving soon after pupil dilatation would be inadvisable)

    • support groups

    • compliance aids (such as dispensers) available from their GP or community pharmacist

    • Letter of Vision Impairment (LVI), Referral of Vision Impairment (RVI) and Certificate of Vision Impairment (CVI) registration

    • Driver and Vehicle Licensing Agency (DVLA) regulations.



[1] At the time of publication (April 2009), MMC and 5-FU did not have UK marketing authorisation for this indication. Informed consent should be obtained and documented. Both drugs should be handled with caution and in accordance with guidance issued by the Health and Safety Executive.

  • National Institute for Health and Care Excellence (NICE)