Denise V. Gobert

Standardization of Automated Analyses of Oculomotor Fixation and Saccadic Behaviors

In an effort toward standardization, this paper evaluates the performance of five eye-movement classification algorithms in terms of their assessment of oculomotor fixation and saccadic behavior. The results indicate that performance of these five commonly used algorithms vary dramatically, even in the case of a simple stimulus-evoked task using a single, common threshold value. The important contributions of this paper are: evaluation and comparison of performance of five algorithms to classify specific oculomotor behavior; introduction and comparison of new standardized scores to provide more reliable classification performance; logic for a reasonable threshold-value selection for any eye-movement classification algorithm based on the standardized scores; and logic for establishing a criterion-based baseline for performance comparison between any eye-movement classification algorithms. Proposed techniques enable efficient and objective clinical applications providing means to assure meaningful automated eye-movement classification.

Distortion and Size Calibration of the Scanning Laser Ophthalmoscope (slo) Laser-beam Raster

Purpose. The Rodenstock scanning laser ophthalmoscope (SLO) is useful for mapping retinal function and for developing and evaluating visual rehabilitation methods. It is essential to know the visual angle subtended by stimuli in the SLO laser-beam raster and to accurately measure angular distances between objects in the final SLO image. To accomplish this, the angular extent of the SLO laser-beam raster must be calibrated. Methods. We developed a simple method and apparatus for calibrating the raster and used it for repeated calibrations during a 3-month period. Results. The laser-beam raster is quite stable in shape and size, but it is trapezoidally distorted in the vertical direction. Consequently, SLO images are distorted. Conclusions. Trapezoidal distortion of the SLO laser-beam raster can cause stimulus size to change as much as 10% from the top to the bottom of the raster. Measurements of fixed horizontal retinal landmark distances in SLO images can also vary as much as 10%. We developed a straightforward mathematical method for correcting distortion in SLO image measurements.

Recovery 9 Years Post Stroke with Standardized Electrical Stimulation

ABSTRACT This case report summarizes results of a new standardized evidence-based treatment protocol regarding neuromuscular electrical stimulation (NMES) and somatosensory stimulation (SS) for a chronic stroke patient. The protocol included treatment five times per week, up to 3 hr per day for 20 months. Treatment included 20 min active NMES followed by two to three hr of SS. Repetitive task practice activities were performed during SS for targeted muscle groups. Remarkable functional recovery was noted with all outcome measures, including the Chedoke-McMaster Stroke Assessment and the Action Research Arm Test, suggesting prolonged NMES and SS therapy should be investigated further.

Visual–vestibular function in patients following an acoustic neuroma resection

Abstract Problem: Clinical evidence suggests a relationship between visual and vestibular function; however, little work has specifically targeted how visual deficits integrate with vestibular function to affect functional balance in postoperative acoustic neuroma patients. Methods: Visual, audiometric, and balance functions were tested in 24 participants (mean age, 46.17 ± 13.107) who were placed into 2 groups: 8 acoustic neuroma patients at least 6 months post a vestibulo-neurosection (PVN), and 16 age-matched controls (NN). Variables of interest included: near and far visual acuity (ACU) using standardized Snellen charts, pure tone averages at 1,000/2,000 Hz (AUD1000 and AUD2000), horizontal and vertical Vestibular Ocular Reflex (VOR) gain (Gain), phase (PHZ), and symmetry (SYM). In addition, functional balance was measured using the combined balance scores from the EquiTest™ Smart Balance Master protocol for Sensory Organization Test (SOT) and lateral bias of the center of pressure (X-bias). All tests were assessed specifically to each side tested (right vs left). Results: Nonparametric statistics using a Kruskal-Wallis H analysis revealed a significant difference in right and left visual acuity: right = 57.86 ± 13.309 vs 170.63 ± 55.985, P = 0.021; left = 72.50 ± 26.617 vs 201.25 ± 61.483; P = 0.050. In addition, there was a significant difference in horizontal VOR phase, 190.760 ± 2.2443 vs 198.225 ± 4.6931, P = 0.001. Balance scores also resulted in a significant difference, 79.27 ± 8.084 vs 66.13 ± 8.896, P = 0.002. All significance levels were tested using the Welch Robust Tests of Equality of Means at the 0.05 level. Conclusion: Results indicate that visual function was also significantly impaired in conjunction with deficits in balance and auditory function in the PVN group compared to the NN group. Significance: These results will aid in developing rehabilitation strategies for functional balance training for patients post an acoustic neuroma resection. Support: Supported in part by a grant from the School of Allied Health in the University of Kansas Medical Center.