New Jersey Neuroscience Institute, JFK Hospital, Edison, NJ 08818, USA.
Invest Ophthalmol Vis Sci. 2010 May;51(5):2476-8. doi: 10.1167/iovs.08-3241. Epub 2009 Sep 8.
Physiologic gaze-evoked nystagmus (GEN) is one of many normal eye movements seen on the neurologic examination. GEN occurring at gaze angles >45 degrees is considered a positive sign in the Horizontal Gaze Nystagmus Test (HGNT) used by United States police officers to determine alcohol intoxication.
The authors enrolled 56 subjects after a brief survey and a neurologic examination yielding normal
Subjects were directed to look at small targets on the wall in primary gaze and at 10 degrees intervals until they reached extreme gaze bilaterally. Eye movements were recorded using infrared video-oculography.
In addition to a high incidence of physiologic GEN at gaze angles 30 degrees and greater (at 30 degrees, n = 43%; at 40 degrees, n = 73%; at extreme gaze, n = 93%), the authors demonstrated that physiologic GEN occurs at smaller gaze angles (at 10 degrees, n = 21%; at 20 degrees, n = 34%).
A significant number of subjects with normal vision have physiologic GEN at gaze angles as small as 10 degrees. This could potentially refute the "failing" grade that is the hallmark of the HGNT and propagates further testing of the validity of this test in the conviction of intoxicated drivers.
生理性视动性眼球震颤（GEN）是神经检查中常见的许多正常眼球运动之一。在用于确定醉酒的美国警察使用的水平眼震测试（HGNT）中，注视角度> 45 度的 GEN 被认为是一个阳性体征。
作者在进行简短的调查和神经检查后招募了 56 名受试者，结果均正常。
要求受试者在直视时看向墙上的小目标，每隔 10 度看向一个新目标，直到双侧达到极限注视。使用红外视频眼动描记术记录眼球运动。
除了在 30 度及更大的注视角度出现生理性 GEN 的高发生率（在 30 度时，n = 43%；在 40 度时，n = 73%；在极限注视时，n = 93%）外，作者还证明生理性 GEN 发生在较小的注视角度（在 10 度时，n = 21%；在 20 度时，n = 34%）。
许多视力正常的受试者在注视角度小至 10 度时就出现生理性 GEN。这可能会反驳 HGNT 的标志性“失败”等级，并进一步验证该测试在判定醉酒司机时的有效性。
