How to get better at OCT

How to get better at interpreting optical coherence tomography (OCT) was the subject of a workshop hosted by Michelle Hanratty at the AOP’s Locum clinical skills conference 2024 (held on 5 November).

OCT is a core skill for many optometrists and is becoming increasingly widespread, Hanratty noted.

Part of successful use of the technology includes clear communication with patients, Hanratty believes.

“A picture is [worth] more than 1000 words, and if you explain that actually, it’s like looking through cling film, they’ll understand why their vision isn’t as good quality as they would like it to be,” she said.

“The best way to get better OCT is to look at lots of them, even when you think the patient is normal,” Hanratty added.

This means performing OCT scans on patients where you might not believe there is anything wrong, she said.

Hanratty advised optometrists to “compare it to their signs, symptoms and their other presentations.”

She added: “Yes, it may be perfect – but you’ll start to get an appreciation of something that looks a little bit different, but is still non-pathological and is still normal.”

She also advised against jumping to conclusions, as this might lead to missing something that does exist.

Cross-referencing OCT with fundoscopy findings and with the patients’ history and symptoms is also important, Hanratty advised.

“With OCT, it’s really good to think about using it to confirm what you think your diagnosis is, and not to rely on it just in isolation,” she said.

Getting a second opinion from a colleague is also often invaluable and is often appreciated by patients, she added.

Easing patients’ fears

“OCT can be a great tool for monitoring, as well as for screening,” Hanratty told attendees.

When taking a patient for extra or repeated scans, it is important that they understand why this is happening, Hanratty said, adding that patients are now often more involved in deciding whether a referral is made than they might have been in the past.

If a scan is being repeated, any lack of communication could lead to the patient being scared, she emphasised, adding that showing patients the OCT image when explaining it to them can help to avoid this.

Explaining that uneven layers can be the reason that the patient does not have perfect vision can be helpful, Hanratty explained.

She noted: “OCT is very visual, and I think you can use that to explain to patient exactly what is going on – or not going on, as the case may be.”

Hanratty also reminded attendees in her workshop that, if working in general practice, they are not expected to be retina specialists, and that they might not fully understand every layer that is present in the OCT scan.

“You can get hung up on knowing what those layers are. From an anatomical point of view, it can be quite difficult to learn what those layers are, particularly if you’re not a specialist in retina,” she said.

The important thing is being able to spot an anomaly, she said, adding that fitness to practise cases would always assess what an optometry peer would have done in the same situation.

She noted that there is not always a right or a wrong, but that evidencing why you have taken a certain course of action is the most important thing.

“It’s making sure that what you do stands up to scrutiny, and can be justified. You’ve always got to be able to evidence why you’ve taken a certain course of action,” she said.