Abstract
Abstract: :
Purpose: This study was performed to provide us more information about the effectiveness of the implantation of a Teledioptric Intraocular lens (TDIOL) as a supplementary magnifying device in combination with the use of a closed-circuit television (CCTV). CCTVs are frequently prescribed to patients suffering from severe or profound low vision. Patients with the need of high magnification often complain about the limited number of characters on the CCTV display. We investigated the possibility to create more characters on the CCTV display with the implantation of a TDIOL. Method: Ten subjects aged from 66 to 88 with best-corrected visual acuities from 20/1000 to 20/200, with cataract and end stage age-related macular degeneration (AMD) and central fixation, participated in this study. Cataract surgery was performed with the implantation of a TDIOL, a retropupillary intraocular lens 7.0 mm diameter with a 1.5 mm diameter minus 56.0-diopter center. Pre- and postoperative visual acuity (VA), magnification requirement for reading and the number of characters on a 17 " CCTV with preferred magnification, were determined. A spectacle with a high power objective lens activated the TDIOL as a Galilean telescope. With activated TDIOL system, VA, magnification requirement and the number of characters was determined again and compared to the outcomes without activating the TDIOL system. Results: In all subjects the presumed mathematical effectiveness of the activated 2x TDIOL system was proved. The number of characters on the CCTV before and after activation of the system showed a significant difference of 8.6 characters (p value = 0.007). Magnification requirement was changed from a mean of 18.4 post-operative to a mean of 12.4 after activation of TDIOLS (p value = 0.009). The TDIOL doubled visual acuity (p value = 0.005), resulting in a decreased magnification requirement and consequently more characters on the display. Conclusion: Despite this proof of effectiveness of the TDIOL system, subjects' satisfaction was poor and 7 of 10 subjects preferred the quality of vision of the non-activated TDIOL.
Keywords: 459 low vision • 539 reading • 308 age-related macular degeneration