Dr Chandra Bala and his patient Joan Brennan
By Helen Carter
A clinical trial of a new lens for cataract patients who also have age-related macular degeneration is showing promising early results, according to ophthalmologist Dr Chandra Bala.
Dr Bala, head of surgery with personalEYES eye clinics, is the only surgeon using the new intraocular lens in Australia as part of a trial to improve the sight of older people with AMD.
His study is in its early stages with increasing numbers of patients joining the trial.
One patient, Joan Brennan, 83, who lives independently, had advanced AMD and cataracts in both eyes. Dr Bala successfully implanted the lenses binocularly in both eyes.
He said Ms Brennan had enjoyed significant improvements to both eyes with remarkable near vision improvement and had experienced no side-effects, glare, halo or distance vision problems.
Her vision has improved to the point where she can read most print and she developed a sporting injury playing bowls as she can now see the jack.
‘Previously Joan couldn’t see the elevator buttons to leave my office,’ Dr Bala said. ‘She has had a marked improvement, with additional help from reading glasses. This lens has reduced the low vision aid power and she no longer carries a hand-held magnifier.
‘The only disadvantage has been a reduction in working distance to 12 centimetres, but she doesn’t seem bothered by it.’
Dr Bala said optometrists could refer for the surgery patients with cataract and visual acuity between 6/15 and 6/120 due to AMD, as the clinic was recruiting for the non-randomised case control study in 190 patients.
‘This is a surgery trial of an asymmetric refractive IOL, Lentis High Add lens, LS-313 MF80, made by Oculentis, Germany. It has a +8 Add, which will theoretically provide x2.4 magnification in the spectacle plane,’ he said.
‘Unlike the intraocular lens for visually impaired people and intraocular miniature telescope solutions used previously, this is a foldable single piece lens which can be inserted as part of a normal cataract operation through a small 2.2 mm clear corneal wound into the capsular bag with sutureless wound closure.
‘This 11 mm acrylic plate lens has a 6 mm optic with two portions; a distance segment which occupies approximately 60 per cent of the optic and an asymmetric refractive near segment which occupies the remainder of the optic.
‘Other lenses are very large and cause a reduction in peripheral vision in order to give a telescopic magnification.’
Dr Bala said the aim was to achieve emmetropia with the distance portion. He said risk of dysphotopsias was not a problem in this group because they did not drive due to poor vision and were not troubled by big magnification because of limited macular function.
The lens is not yet on the market but he said it was available free through the trial and should fall under Medicare.
Dr Bala is also a clinical senior lecturer at Macquarie University and adjunct senior lecturer at the University of New South Wales.
For information see www.personaleyes.com.au or call 02 8833 7111. Patients with cataract and AMD are eligible but must not have glaucoma or corneal problems. If the trial is successful, the clinic will consider patients who have had IOL for explant surgery.