Today’s visual environment has evolved dramatically in recent years. Within what seems a blink of an eye, our focus has been concentrated to an arm’s length away and workload seems to be reaching a critical mass. Smartphones were launched just 10 years ago with the first Apple iPhone.
Now, more than 80% of Americans own a smart phone. Six years ago, Apple’s first-generation iPad tablet was released and now 50% of Americans own one. These new devices differ from our traditional computers, not only in their size and portability, but how close we hold them to our eyes. The barrage of digital media devices and the constant access to information has brought with it increased levels of eye strain, even in young people.
The Hoya Nulux Active
Hoya’s Sync lens, known as Nulux Active in Europe and Remark in Asia, has been designed to address the rigours of our new visual world by creating an area of relaxation when undertaking near tasks, while at the same time reducing the distortion that a progressive lens typically presents. The lens design helps promote visual comfort, especially for those with high digital media usage.
Figure 2: Horizontal and vertical aspherisation in the Nulux Active
The Nulux Active, was created to help all ages with these new visual demands, but has particular relevance for the younger patient for whom the increased visual demand has been most dramatic (figure 1). Indeed, this group spent most of their waking hours involved in some form of digital screen use. In fact, schools are taking this portable technology into the classroom. Books are becoming digitally converted and apps are increasingly being used for creative learning. Our children have taken to this new technology in droves. Not surprisingly, just as digital screen use becomes the norm, so does the increased prevalence of eye strain symptoms.
Figure 3: Accommodative support shifts gradually towards values up to +0.53 DS (Nulux Active A) or +0.88 DS (Nulux Active B)
A study
How successful Nulux Active can be in helping relieve these visual symptoms is the basis for this study. The Nulux Active lens is a back surface (‘Trueform’) optimised lens that has a vertical aspheric front surface and an aspheric or atoric back surface with soft progression distribution over the entire surface (figure 2).
The asymmetric design creates an edge to edge active area, offering +0.88DS (Nulux Active B) or +0.55DS (Nulux Active A) accommodative power support (figure 3). The asymmetric vertical aspherical design generates overlapping retinal images so improving visual comfort when there is transition across any single view (figure 4).The study required 12 optometrists to prescribe the Nulux Active lens over a six to eight-week period to patients that fell within the criteria of our study.
These criteria related to the amount of time spent on a tablet/smartphone and/or on a computer, as well as, the presence of symptoms of eyestrain. When the symptoms were significant and the near visual demand high, Nulux Active lenses were prescribed to determine if any resolution of eye strain would result. From the 12 optometrists, 87 patients were found to fill the criteria.
Method
Each optometrist was asked to prescribe Nulux Active when they deemed its use beneficial in situations where extensive eye strain was noted. The age was unimportant, but ideally patients were under 45 years old. When a patient was selected for the study, they were asked to note any one or more symptoms of eye strain. These symptoms included:
- Headaches
- Fluctuation in vision
- Light sensitivity
- Tired eyes
- Dry eyes
- Poor night vision
- Eye rubbing
- Decreased concentration at near
- Eye twitching
- Vertigo
- Double vision
- General fatigue
Each patient also described the amount of time they spend on a tablet/smartphone and a computer on an average day. The values ranged from less than one hour, one to three hours, four to six hours, seven to nine hours, and greater than 10 hours. A brief description of the reasoning for prescribing the Sync lens was also offered by the practitioners.
After two to four weeks, there was a follow-up with the patient required to document their overall satisfaction with the Nulux Active lenses. This follow-up information was submitted to the optometrists as a summary of patient comfort.
Findings
Eighty-seven patients were enrolled into the Nulux Active lens study. The ages of the patients ranged from seven to 55 years old, with an average age of 26.14 years old and a median age of 26 years old.
Digital device usage
Time spent on different digital devices varied, but most time was given to computer usage. Of the 87 patients, 78 reported spending time at a computer. Time spent was broken down as follows;
- 92% used a computer for between one and nine hours a day.
- 54% used the computer one to six hours a day.
- 52% were on a computer for four to nine hours a day.
- 29% used a computer for one to three hours a day.
Tablet/smartphone use showed a tighter grouping.
- 69 patients responded to using a tablet/smartphone on an average day.
- 80% fell within the one to six hours a day of use.
- 35 patients fell within the one to three hours a day category, representing 51% of the patients.
The tallies for usage are summarised in table 1.
Table 1: Hours of use of different digital devices by different age groups
Symptoms
Each patient was asked to note all their symptoms regarding eye strain. From the 87 patients, 239 symptoms were stated. This works out at 2.8 symptoms per patient. We adjusted the tally to 228 by removing eye twitching (three responses), vertigo (three) and diplopia (six) from the list as their severity was minimal. The commonest reported symptom of eye strain taken from the list was ‘fluctuation in vision’, with 45 complaints or 52% of the patients. Tired eyes (38 complaints) and headaches (37 complaints) were not far behind. Closely following with 34 complaints was ‘general fatigue’. The numbers of reported eye strain complaints tailed off from there, with ‘decreased concentration’ (27 complaints), ‘decreased vision at night’ (20), ‘dry eyes’ (20), ‘photophobia’ (15) and ‘eye rubbing’ (12). See table 2.
Table 2: Eye strain symptoms in digital device users of different ages
Follow up
Patient satisfaction with how well they adapted to the new lenses and any influence upon symptoms was determined by a follow up phone call or interview at the revisit to the optometrist. Each practitioner recorded a brief description of responses from the patient. These responses were assessed in terms of either a positive or a negative attitude.
Eighty-seven patients entered the study, but 11 were lost in follow up. Seventy-six patients gave their follow up responses to their new Nulux Active lens use as follows:
- 20 were ‘extremely happy’.
- 44 were ‘happy’.
- Eight were ‘just satisfied’ with their new lenses.
- Four patients were ‘unhappy’ with their Nulux Active lens experience.
- Two reported being ‘uncomfortable’ with the distortion.
Both latter patients had been wearing single vision free form lenses before trying the Nulux Actives. Overall, 64 patients or 84% of the Nulux Active study patients were happy or very happy with the Nulux Active lens and its ability to reduce their eye strain symptoms. Only 5% found the Nulux Active lens uncomfortable or ineffective in its ability to reduce their eye strain.
Conclusion
While this was a limited study in terms of sample size and its reliance on subjective responses, the overwhelming positive results of the patient base to resolve their eye strain were considered to be of significance. In a world where digital devices are becoming the norm in such a short period, digital media strain to the visual system will not just be a problem of the presbyope. Eye care practitioners need to be ready to offer solutions to problems arising.
Thomas Gosling is an optometry consultant based in Colorado, US.