Hermann D. Schworm

Drift in Ocular Counterrolling during Static Head Tilt

Abstract: A decreasing drift of the counter‐rolled eye position (OCR) during head tilt was recently described. The underlying mechanism is not known. OCR in eleven healthy subjects was recorded (Search coil, Skalar) during a head tilt paradigm in two test conditions. The head was tilted with a velocity below (test 1) and above (test 2) detection threshold for the semicircular canals (SC) and held static for eight minutes. A significant drift of OCR was revealed in test 2 (P = .0006, ANOVA) and close to significant in test 1 (P = .07). No statistical difference was found between the two test conditions. The results suggest that the OCR drift was not caused by the SC complex merely.

Dynamic Changes of Eye Cyclo Position during Head Tilt

In maintaining steady vision during locomotion the eyes have to make compensatory rotations to the movements of the head, that is, the vestibulo ocular reflex (VOR). The semicircular canals detect rotary (r-VOR) and the otoliths detect linear (t-VOR) movements of the head.1 When a subject performs head tilt (roll), the ipsilateral eye elevates and the contralateral eye depresses. An ocular counter-rolling (OCR) in the opposite direction to head tilt is also induced. The dynamic shift in torsional position is usually attributed to the semicircular canals and the stable post-tilt OCR is attributed to the otoliths. Recent findings2 suggest that the otoliths contribute to the dynamic changes of eye position as well. Our aim with this study was to evaluate the dynamic changes of eye position in response to head tilt, and to try to differentiate the input from the canals and the otoliths to provide a better understanding of the r-VOR dynamics.

Changes of saccadic eye movements in thyroid‐associated ophthalmopathy

Purpose:  To establish whether or not the dynamics of saccadic eye movements are significantly changed in patients with different stages of thyroid‐associated ophthalmopathy (TAO) and, subsequently, if analysis of saccades could serve as an additional diagnostic tool for early detection of inflammatory activity in TAO.