Videoculography (VOG) is simpler and has lower invasiveness than other eye movement measuring methods, such as electro-oculography and the search coil method. Thus, it is advantageous for educational and clinical applications. Recently, VOG has been used to measure eye movements as orienting reflexes for applying this to perimetry. The neural mechanisms of the orienting reflex remain unclear. However, it is believed that the geniculate pathway strongly associated with consciousness and the involuntary reflex pathways via the superior colliculus generate the reflex. Therefore, VOG perimetry is potentially more suitable for evaluating the impact of visual field loss on daily life and motor performance because conventional visual field testing requires patients to perform a non-routine behavior that patients maintain fixation and press a button when they perceive a visual target. Eventually, VOG perimetry would provide new insight into our visual system.

【Purpose】We examined the differences in corneal power of table-mounted and handheld keratometers with different light configurations.

【Methods】Corneal power was measured from the right eyes of 189 university students (aged 20.2±1.2 years) with no eye disease other than refractive error using four types of auto-keratometers and analyzed using power vector analysis.

【Results】The mean corneal power was 43.37 for TONOREF II, 43.40 for ACOMOREF 2, 43.38 for Retinomax K+Screeen (RMS), and 43.49 [D] for Retinomax K-plus3 (RM3), with RM3 having a significantly higher value (p＜0.001). J0 was significantly positive for RM3 (p＜0.001), and J45 was significantly different in each group (p＝0.002 to ＜0.001), except between ACOMOREF2 and RM3.

【Conclusion】Although there were significantly different in corneal power in keratometer models, these differences were not clinically relevant (＜0.25 D).

The pupil and optokinetic nystagmus (OKN) change not only by the luminance and the direction of the motion at the eye position but also by that at the attended location. This study demonstrates that it is possible to estimate when a human switches attention by measuring pupillary response and OKN. An information-input interface was developed in which pupillary responses and OKN are used to identify a visual stimulus targeted by a user's attention. In Experiment 1, random dots with different directions of motion and brightness were presented in superposition. In Experiment 2, random dots with different directions of motion and brightness were presented at different locations. When a target letter was presented, participants switched their attention to the dot pattern with the same direction of motion and brightness as the target letter. The pupillary and OKN changes corresponded to the luminance and direction of the attended pattern when the participant switched attention to the target letter in the eye position. This finding suggests that pupillary responses and OKN can be used to identify which letter a user intends to select.