1: Begin by understanding what the patient’s vocational and recreational visual needs are
Occupational lenses (OPPLs) were invented due to the ever growing usage of multiple devices/tools at a variety of working distances for a prolonged period of time. Such changes in our lifestyles mean that our visual needs cannot be fulfilled by conventional progressive powered lenses. It is, therefore, vital to ask your patient what type of close-range activities they do, both professionally and for pleasure. Ask open questions and allow your patient to describe what their daily tasks involve. Use this information to tailor your advice to find a solution (or solutions) that best suits their lifestyle.
2: What is their work environment like?
Do they use one screen or multiple VDU devices? What kind of digital devices do they use and how far away do they hold them? What is their natural sitting position? Do they have a standing desk? Does their work environment change between working at home vs in the office? Again, such information can be obtained by asking open questions and carefully listening to their answers. This will be the key to successfully dispensing OPPLs in order to provide the most comfortable visual experience, ultimately leading to full patient loyalty.
3: The bond between timing and working distances
In practice we commonly hear: ‘I spend seven or eight hours a day looking at a screen. This statement is ambiguous and needs further dissecting. If your patient is mainly using a laptop at approximately 45-50cm away, they will need a larger near zone. In comparison if your patient is working in an ergonomically designed office where their screen is at eye level and at approximately 65-75cm away, they will need a more balanced design of OPPLs. This will enable them to make notes, use their phone and use their PC monitor comfortably. Imagine that your patient is an IT technician or a financial trader using three screens adjacent to one another at eye level – you should consider enlarging the intermediate zone. Think about tailoring the lens to produce a wider corridor width so the wearer does not feel restricted when looking to the side. Alternatively, a dedicated single vision intermediate pair is also a good solution for such professions.
4: Tailor each lens pair to visual needs and occupational set-up
Individualised lenses such as Hoya Workstyle and Zeiss Officelens Individual use the latest freeform technology, which takes into account the vertex distance, pantoscopic tilt and faceform angle to create a digitally enhanced visual performance for the wearer. A unique lens is produced for each dispense where the surface aberrational astigmatism (this is known as ‘distortion’ in practice) is pushed further into the periphery of the lens. Use this technology to your advantage in addition to your judgment as a dispensing optician to expand the most desired visual zone.
5: Don't underestimate lens treatments and filters
In my opinion, applying an anti-reflection coating is a must on all lenses to reduce surface reflections. If a patient is light sensitive or suffering from glare, consider a grade 0 (15% ABS) grey tint to reduce the amount of light entering the eye, thus reducing glare. Grey is a neutral colour, so screen colours will not be distorted. Ask questions about sitting position and lighting with particular reference to direct sunlight hitting the screen. The controversial blue control filter has had a massive growth during the pandemic period via social media and online retailers. Ensure you provide the correct advice for the heavy screen users and clarify any misconceptions they may have.
6: Advise on the lens limitations and manage expectations
Explain to each patient exactly how the lenses will work and the positioning of the different visual zones in order to avoid any surprises on collection. For example: ‘There will be a smooth transition in power when looking from the top to the bottom of the lens. Looking at eye level you will find the intermediate zone, which is specifically designed for your working distance using a PC. When looking at your phone, reading a book or using a laptop, you will naturally tilt your head down and access the bottom of the lens where you will find your full near correction. Ensure that you are moving your head directly at what your wish to look at. Do not use the lenses for any outdoors activities or driving. Take care when walking around the house and going down stairs.’ Keep your advice concise and note everything down.
7: Move onto frame selection that is fit for purpose
Guide your patient to try on frames with an adequate B measurement suitable for the multiple progression zones. Ideally the pupil centre should be positioned above the horizontal centre line (HCL) to allow enough space for the transition into the near zone beneath the HCL. Refer to your chosen lens supplier’s manual for specific fitting information such as minimum fitting heights. Make the process informative but enjoyable for the patient.