Article

Eye-movement-based assessment of visual function in patients with infantile nystagmus syndrome.

The Daroff-Dell'Osso Ocular Motility Laboratory, Louis Stokes Cleveland Department of Veterans Affairs Medical Center and CASE Medical School, Cleveland, Ohio 44106, USA.
Optometry and vision science: official publication of the American Academy of Optometry (Impact Factor: 1.53). 09/2009; 86(8):988-95. DOI: 10.1097/OPX.0b013e3181b2f2ee
Source: PubMed

ABSTRACT Infantile Nystagmus Syndrome (INS) is an ocular motor system dysfunction characterized by the rhythmic to-and-fro oscillations of the eyes. Traditionally, the assessment of INS visual function solely focused on null- or primary-position visual acuity. Our purpose is to use the past four decades of INS research to introduce a more complete assessment of visual function in patients with INS.
All eye-movement data were obtained using high-speed digital video, infrared reflection, or scleral search coil systems.
We have introduced four important aspects of a more complete INS visual function assessment: the eXpanded Nystagmus Acuity Function and visual acuity measurements in primary position; broadness of the eXpanded Nystagmus Acuity Function peak and high-acuity field; target acquisition time; and gaze-maintenance capability.
Visual function in patients with INS is multifactorial and the simple assessment of primary position visual acuity is both inadequate and may not be the most important characteristic in overall visual function. A more complete visual function assessment should also include primary and lateral gaze eye-movement and visual acuity examinations, target acquisition time and gaze holding.

0 Bookmarks
 · 
83 Views
  • [Show abstract] [Hide abstract]
    ABSTRACT: We developed a new data analysis algorithm called the automated nystagmus acuity function (ANAF) to automatically assess nystagmus acuity function. We compared results from the ANAF with those of the well-known expanded nystagmus acuity function (NAFX). Using the ANAF and NAFX, we analysed 60 segments of nystagmus data collected with a video-based eye tracking system (EyeLink 1000) from 30 patients with infantile or mal-development fusional nystagmus. The ANAF algorithm used the best-foveation positions (not true foveation positions) and all data points in each nystagmus cycle to calculate a nystagmus acuity function. The ANAF automatically produced a nystagmus acuity function in a few seconds because manual identification of foveation eye positions is not required. A structural equation model was used to compare the ANAF and NAFX. Both ANAF and NAFX have similar measurement imprecision and relatively little bias. The estimated bias was not statistically significant for either methods or replicates. We conclude that the ANAF is a valid and efficient algorithm for determining a nystagmus acuity function.
    The British journal of ophthalmology 11/2010; 95(6):832-6. · 2.92 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: To evaluate the efficacy of a computerized optokinetic nystagmus (OKN) test for determination of objective visual acuity (VA) at distance in patients with various ocular diseases. This is a prospective, non-interventional study that included 85 eyes of 71 patients with one or more ocular pathologies. Study patients were classified into group C (39 eyes of 30 patients with central visual damage), group P (24 eyes of 20 patients with peripheral visual defect) and group M (22 eyes of 21 patients with media opacity). Objective distance VA was measured with OKN induction and suppression methods, and the correlation between the objective and subjective VA at distance was evaluated using linear regression analysis. Mean subjective VAs were compared among each objective VA step and among the three groups. Significant correlation was found between subjective distance VA and objective VA determined by both OKN induction and suppression methods in all three groups and in overall patients. In overall patients, the mean subjective VA was significantly different in several objective VA steps (Welch's ANOVA, p < 0.001 for induction and suppression methods). No significant difference in subjective VA among the three groups was found in any objective VA step. Our objective VA test using OKN induction and suppression methods can be useful in estimating distance VA in patients with various ocular diseases.
    Albrecht von Graæes Archiv für Ophthalmologie 05/2011; 249(9):1379-85. · 1.93 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Objective To perform the first randomized controlled trial comparing soft contact lens (SCL) with rigid gas-permeable lens (RGPL) wearing in infantile nystagmus (IN), using spectacle wear as a baseline. Design Randomized, controlled cross-over trial with an intention-to-treat design. Participants and Controls A total of 24 participants with IN (12 idiopathic, 12 with albinism). Methods Participants were randomized into 1 of 2 treatment arms receiving the following sequence of treatments (2–3 weeks for each treatment): (A) spectacles, SCL, RGPL, and spectacle wear; or (B) spectacles, RGPL, SCL, and spectacle wear. Main Outcome Measures The main outcome measure was mean intensity of nystagmus at the null region viewing at 1.2 m. Secondary outcome measures included the same measure at 0.4 m viewing and across the horizontal meridian (measured over a ±30° range at 3° intervals) for distance and near. The nystagmus foveation characteristics were similarly assessed over ±30° and at the null region at 1.2 m and 0.4 m viewing. Visual outcome measures included best-corrected visual acuity (BCVA) at 4 m and 0.4 m, gaze-dependent visual acuity (GDVA) (i.e., visual acuity when maintaining gaze angles over a ±30° range at 10° intervals) at 4 m, and reading performance at 0.4 m derived from the Radner reading chart. Results There were no significant differences between SCL and RGPL wearing for any nystagmus characteristics or compared with spectacle wearing. The BCVA, reading acuity, and critical print size were significantly worse for SCL wearing compared with RGPL and baseline spectacle wear (P<0.05), although mean differences were less than 1 logarithm of the minimum angle of resolution (logMAR) line. Conclusions Nystagmus was not significantly different during SCL and RGPL wearing in IN, and contact lens wearing does not significantly reduce nystagmus compared with baseline spectacle wearing. The wearing of SCL leads to a small but statistically significant deterioration in visual function compared with both RGPL and spectacle wearing at baseline, although mean effect sizes were not clinically relevant.
    Ophthalmology 01/2014; · 5.56 Impact Factor

Full-text (2 Sources)

View
2 Downloads
Available from
Aug 26, 2014