Abstract
Purpose:
Patients often report that floaters can have a significant impact on vision, but the exact mechanism is unknown. Contrast sensitivity function (CSF) and patient well-being were evaluated prospectively in patients with floaters treated by vitrectomy with the hypothesis that patients with bothersome floaters have a reduction in CSF that can be normalized by vitrectomy.
Methods:
CSF was prospectively studied by computer-based Freiburg Acuity Contrast Testing [Weber index: %W = (Lummax - Lummin)/ Lummax] in 38 eyes of 22 patients. Patients with floaters (N = 8; 51± 23 years) were tested before vitrectomy and results were compared to age-matched controls (N=30; 53 ± 15 years). Minimally-invasive, sutureless 25 G vitrectomy was performed. Patient well-being was quantified pre-operatively in 16 subjects with the validated NEI visual function questionnaire-39 (VFQ-39) using the composite index of all 39 questions, as well as four other sub-indices [mental health, role difficulties, general vision and near vision]. CSF measurements and VFQ evaluations were repeated post-operatively at 1 week and 1 month as outcome measures.
Results:
Pre-operatively, patients with floaters had 54.4% attenuation in CSF (5.39 ± 2.55 %W) compared to controls (2.93 + 1.2 %W; P < 0.003). Post-operative CSF normalized at 1 week (2.44 ± 1.87 %W; P < 0.019) and 1 month (2.26 ± 1.29 %W; P < 0.016). By VFQ testing, mental health, role difficulties, general vision, and near vision improved 83.8% (P<0.01), 69.4% (P < 0.016), 54.9% (P<0.004), 41.2% (P<0.034), respectively, with a composite VFQ-39 improvement of 29.5% (P < 0.006) at 1 month post-operatively.
Conclusions:
Profound CSF diminution establishes a clear basis for significant dissatisfaction in patients with floaters as demonstrated by standardized VFQ testing. Vitrectomy dramatically normalized CSF in patients with floaters and may explain the observed improvement in patient well-being as determined by VFQ testing. Assessing patients with objective measures of contrast sensitivity and standardized quality of life questionnaires may provide useful guides for patient selection when considering vitrectomy for floaters.
Keywords: 762 vitreoretinal surgery •
478 contrast sensitivity •
669 quality of life