Gonioscopy — PCAG / PACG
Assesses the eye's drainage angle conformation. Primary closed-angle glaucoma is linked to how the angle is formed — gonioscopy grades that risk on a three-point scale.
Gonioscopy & glaucoma
Screening for inherited glaucoma risk
Gonioscopy examines the eye's drainage angle and grades the result on a clear three-point scale — helping you and your breeder make informed decisions.
£65 / dog
gonioscopy or POAG test
Registered eye scheme panellist
BVA
KC
ISDS
BVA · KC · ISDS
Eye scheme testing panel member
CertVOphthal
RCVS Certificate in Veterinary Ophthalmology, 2011
Since 1997
Qualified, University of Glasgow
Liverpool
Lecturer to undergraduate & new-graduate vets
What is glaucoma?
Glaucoma is a condition in which pressure builds within the eye. It can be painful and, if untreated, can lead to loss of sight. Some forms are inherited, which is why screening matters in predisposed breeds.
Two inherited types are screened through the eye scheme — each assessed differently, depending on your dog's breed requirements.
- Identify inherited glaucoma risk before symptoms appear.
- Record findings on your dog's eye scheme certificate.
- Support responsible breeding in at-risk breeds.
Two inherited types
Which test does your dog need?
The test required depends on breed. Check the BVA breed lists, or use our quick guide if you're unsure.
POAG test
Examines primary open-angle glaucoma — an inherited form seen in certain breeds, where the drainage angle appears normal but glaucoma still develops.
The gonioscopy procedure
Gonioscopy uses a special lens to view the drainage angle of the eye. Iona examines the angle and grades how much of it appears abnormal, which indicates the level of risk.
The result is recorded on your dog's eye scheme certificate and can inform breeding decisions, particularly in breeds where glaucoma risk is a concern.
- Carried out in a single appointment using a specialist gonioscopy lens.
- Both eyes are examined and graded individually on the three-point scale.
Grading
The three-grade scale
Gonioscopy results are graded by how much of the drainage angle appears abnormal. The grade is recorded on your dog's certificate and can inform breeding decisions.
Grade 1
≤ 25% abnormal
Normal / mildly affected
Grade 2
26–75% abnormal
Moderately affected
Grade 3
> 75% abnormal
Severely affected, at risk
Ready when you are
Book your dog's eye test.
Secure your appointment in a few minutes with a £25 deposit. The balance is paid on the day, by card.
- Painless, 30-minute appointment
- Findings recorded on the eye scheme certificate
- £25 deposit, balance paid on the day