Parulekar Manoj V, Dai Shuan, Buncic J Raymond, Wong Agnes M F
Department of Ophthalmology and Vision Sciences, The Hospital for Sick Children, 555 University Ave, Toronto, ON M5G 1X8, Canada.
Arch Ophthalmol. 2008 Jul;126(7):899-905. doi: 10.1001/archopht.126.7.899.
To investigate whether ocular torsion and vertical misalignment differ in the upright vs supine position in skew deviation and to compare these findings with those in trochlear nerve palsy.
Ten patients with skew deviation, 14 patients with unilateral peripheral trochlear nerve palsy, and 12 healthy subjects were prospectively recruited. With subjects first in the upright position and then in the supine position, ocular torsion was measured by double Maddox rods and vertical misalignment was measured by the prism and alternate cover test.
In patients with skew deviation, the abnormal torsion and vertical misalignment in the upright position decreased substantially with change to the supine position, whereas in patients with trochlear nerve palsy, it changed little between positions. Torsion was decreased by 83% in patients with skew deviation, 2% in patients with trochlear nerve palsy, and 6% in healthy subjects (P < .001). Similarly, vertical misalignment was decreased by 74% in patients with skew deviation and increased by 5% in patients with trochlear nerve palsy and 6% in healthy subjects (P < .001).
Our findings provide the basis for additional clinical tests to support the classic 3-step test: ocular torsion and vertical misalignment that decrease from the upright position to the supine position indicate skew deviation, whereas torsion and vertical misalignment that do not change significantly between positions indicate trochlear nerve palsy.
研究在垂直分离性偏斜中，直立位与仰卧位时眼扭转和垂直斜视的差异，并将这些结果与滑车神经麻痹的情况进行比较。
前瞻性招募了10例垂直分离性偏斜患者、14例单侧外周滑车神经麻痹患者和12名健康受试者。受试者先处于直立位，然后处于仰卧位，通过双马多克斯杆测量眼扭转，通过棱镜交替遮盖试验测量垂直斜视。
在垂直分离性偏斜患者中，直立位时异常扭转和垂直斜视在变为仰卧位时大幅降低，而在滑车神经麻痹患者中，不同体位间变化很小。垂直分离性偏斜患者的扭转降低了83%，滑车神经麻痹患者降低了2%，健康受试者降低了6%（P < .001）。同样，垂直分离性偏斜患者的垂直斜视降低了74%，滑车神经麻痹患者增加了5%，健康受试者增加了6%（P < .001）。
我们的研究结果为支持经典三步试验的额外临床检查提供了依据：从直立位到仰卧位时眼扭转和垂直斜视降低提示垂直分离性偏斜，而不同体位间无明显变化提示滑车神经麻痹。
