My take on...OCT

Dr Louise Terry 

“I regularly use optical coherence tomography (OCT) in practice and my research has highlighted how important and useful the technology is to me. I now struggle to see how optometry and ophthalmology would be without it. Given the rate that technology has advanced recently, I expect a wealth of new and exciting techniques for imaging the retina and other structures of the eye to be developed over the coming years.

“So, what’s next for OCT? OCT-angiography (OCT-A) is an adaptation of standard OCT devices with the additional ability to detect blood flow in the retina. It can be used to investigate changes to blood flow in conditions such as macular degeneration and diabetic eye disease. Currently, retinal blood flow is usually assessed using fluorescein angiography. This involves injecting a dye called fluorescein into a vein in the arm and taking a series of retinal photographs as the dye moves through the blood vessels in the retina. Fluorescein is so named because it fluoresces under blue light, highlighting areas where blood is (and isn’t) reaching. This can alert the clinician to any blocked or leaking vessels. Unfortunately, injection of fluorescein can cause a number of adverse reactions, including nausea and vomiting, increased heart rate, and in rare cases, severe allergic reaction. OCT-A allows safe imaging of blood flow without the need for injections and can be carried out on the High Street, making it accessible to the general public without the need for a hospital visit.

“Another likely addition to healthcare in the near future will be computer-aided diagnosis. These tools can be used by professionals to assist with detecting disease and making clinical decisions. For example, OCT images may be reviewed by inbuilt software, which will determine the likely diagnosis for that patient. The results can then be reviewed by a clinician, who will determine the final diagnosis. These tools are not designed to substitute the clinician, rather to play a supporting role in detecting and diagnosing abnormalities. This aims to improve patient care by increasing the accuracy and speed of diagnosis.”

Dr Neelam Patel

“OCT has revolutionised ophthalmology and secondary care services for eye health. A greater uptake of OCT in primary eye care could now transform community optometry. OCT is able to offer better diagnostic capabilities, enhance referrals and enable monitoring of low-risk and stable ocular conditions. As OCT technology advances further, it may lead to development of additional eye care services, for instance, around the management of conditions associated with the retinal vasculature, choroid and vitreous.

“OCT instruments are becoming increasingly compact, user-friendly and time efficient, making them well-suited to community optometry. Many manufacturers now offer OCT instruments as part of a lease agreement, making them more manageable as an investment. Practices need to consider staff training, patient pathways and professional fees.

“I see OCT becoming an integral part of primary eye care in the UK, particularly with an ageing population. However, as OCT is not a part of the current NHS General Ophthalmic Services (GOS), practices have no choice but to offer OCT as an optional private service to NHS patients. This poses a risk of increased health inequality in areas of socioeconomic deprivation and may contribute to much-needed reforms in the current NHS GOS. This may be resolved with developments of NHS-funded enhanced community services based around OCT services.” 

Image credit: Paul Ligas