Videos

Files in this Data Supplement:

• Bielschowsky.mov - (15.2 MB)
  Documentation of dynamic Bielschowsky head-tilt test. First scene: three-dimensional turntable oscillating ±35° at 0.3 Hz. Second scene: binocular and monocular video recording during oscillation of a patient with acquired left trochlear nerve palsy in right gaze. The paretic left eye was covered with a cyan filter blocking the red laser light but allowing video recording. Increasing hyperdeviation of the covered eye with intorsion. Third scene: computer animation of desaccaded original search-coil data of the same patient at the same gaze direction as in scene two. Red lines indicate instantaneous ocular rotation axes. Axis of the covered eye is shifted nasally relative to the axis of the fellow eye and away from the line of sight.

• Example_Patient.mov - (2.87 MB)
  (Complementary to Fig. 4, but a different patient.) Acquired right trochlear nerve palsy. Patient looking at nine different target directions during sinusoidal head roll with the palsied eye covered. Rotation axis of viewing eye roughly aligns with the line of sight. Rotation axis of covered eye deviates nasally relative to the axis of the fellow eye, but remains fairly stable.

• Hess_Screen.mov - (4.12 MB)
  (Complementary to Figs. 1 and 4, but different patient.) Reconstruction of Hess screen grid during dynamic Bielschowsky head-tilt testing of a congenital right trochlear nerve palsy. For every gaze direction, mean eye position during oscillation cycles was calculated for each chair position in steps of 1°. Covered right eye: red. Viewing left eye: blue.

• Geometric_Model.mov - (2.53 MB)
  (Complementary to Fig. 7D.) Computer animation of geometric two-step model simulating right trochlear nerve palsy. Left healthy eye (viewing): sinusoidal ±10° torsion about the line of sight in nine different gaze directions. Right affected eye (covered): rotation about a stable rotation axis (red line) deviated 15° nasally relative to the axis of the healthy eye and not aligned with the line of sight.

• Eyelab_Model.mov - (2.95 MB)
  (Complementary to Fig. 10.) Computer animation of EyeLab model simulating right trochlear nerve palsy. Left viewing eye (healthy: model input): sinusoidal ±10° torsion about the line of sight at nine different gaze directions. Right covered eye (affected: model output): oscillating deviation of rotation axis (red line) toward the nose and vertical deviation of gaze as a function of torsion.