Tucked away in a private space outside our examination room stands our mighty Humphrey visual field analyser (‘HFA’ to its friends), imposing and proud as a bull elephant. To the casual observer it may lack a certain finesse, that’s true, but any optometrist will know that this mammoth machine is a deceptively delicate bit of kit that sets the gold standard for visual field testing. It simply can’t be beaten for accuracy, and that’s why I love it.
Essential glaucoma assessment tool
Glaucoma clinics around the country recognise the power of the HFA and consider it an indispensable assessment tool for their patients. Not only are the tests reliable, but the reproducibility is excellent, which is paramount in our practice. At Taank, we use the HFA daily to perform visual field screening and to eliminate concerns regarding headaches and unusual symptoms reported by patients.
As part of my work at the Addenbrooke’s Hospital glaucoma clinic, we perform gonioscopy, pachymetry and Sita Fast visual fields to help us triage glaucoma referrals. In this way, we ensure that only those people in need of an ophthalmological referral are sent to the glaucoma clinic.
The performance of the HFA provides peace of mind that the visual fields are clear and gives us confidence that glaucoma is not present.
"The HFA is not without its challenges, of course. One of which is the ‘Marmite’ reaction it provokes amongst our patients, who either love it or hate it"
Managing patient responses
The HFA is not without its challenges, of course. One of which is the ‘Marmite’ reaction it provokes amongst our patients, who either love it or hate it. Most often we hear people remark, “I love playing this, it’s like a game of space invaders.” Or, “I get to be a pirate, this is the best bit!” The competitive types will say, “Did I get them all right? I should get a prize.”
However, for some patients, visual field testing provides a genuine challenge. Some are anxious about missing points, particularly if they’re already worried about their eye health or have a family history of glaucoma. In addition, they may find it difficult to sit and concentrate for the duration of the test due to fixation issues or postural problems.
That’s why we’re always at pains to anticipate these challenges and deal with them sympathetically. It’s imperative that every patient is made to feel at ease, never rushed, and treated with empathy as we make the necessary adjustments to ensure the best test results possible.
Aside from ensuring that our patient is well looked after during the test, we remain resolute in our focus on accurate triaging. The HFA plays a key role in ensuring that only those patients who require further assessment are referred to hospital.
A trusted and reliable optical instrument, the HFA has both a screening and diagnostic function (of parallel importance at our practice), which is why we couldn’t live without it.