Weissberg E, Lyons S A, Richman J E
New England College of Optometry, Boston, Massachusetts, USA.
Optometry. 2000 Mar;71(3):183-8.
A 44-year-old woman came to us with a chief symptom of "jumping letters side-to-side, which is most noticeable while reading." The onset occurred after she had experienced a closed head traumatic brain injury 3 years earlier. Several neuro-ophthalmologists diagnosed a fixational instability secondary to saccadic intrusions and prescribed Gabapentin, which provided minimal relief.
The term saccadic intrusions refers to an inappropriate saccade with a disrupting effect on fixation. Our examination revealed a myopic anisometropia. Motility testing confirmed saccadic intrusions that lessened on occlusion of either eye and superior gaze. A plano spectacle with six-prism diopter-yoked base down was used to position the eyes in the superior null point. Electro-oculography, using the Visagraph II, demonstrated pre and post changes with the prism. The uncorrected anisometropia allowed the patient to be monocular under binocular viewing conditions.
The case report focuses on fixational problems that may occur secondary to traumatic brain injuries. There is evidence that the origin of the problem may be from uninhibited brain stem circuits. Pharmacological treatment may only offer transient improvement. The responsibility of a functional cure is often placed on the optometrist.
This case demonstrates how an alternative use of prism and prescription application can play an important role in the management of fixation dysfunctions.
一名44岁女性前来就诊，主要症状为“阅读时字母左右跳动，最为明显”。发病于3年前她经历闭合性颅脑外伤之后。几位神经眼科医生诊断为继发于眼球跳动性侵入的注视不稳定，并开具了加巴喷丁，但缓解效果甚微。
眼球跳动性侵入是指对注视有干扰作用的不适当扫视。我们的检查发现有近视性屈光参差。眼球运动测试证实存在眼球跳动性侵入，遮盖任何一只眼及向上注视时侵入减轻。使用一副带有6棱镜屈光度、底向下的双眼同向棱镜的平光眼镜将眼睛置于上方零点位置。使用Visagraph II进行的眼电图检查显示了使用棱镜前后的变化。未矫正的屈光参差使患者在双眼观察条件下可单眼视物。
该病例报告聚焦于创伤性脑损伤继发可能出现的注视问题。有证据表明问题的根源可能来自不受抑制的脑干回路。药物治疗可能仅提供短暂改善。功能性治愈的责任通常落在验光师身上。
本病例展示了棱镜的另一种应用方式及处方应用在注视功能障碍管理中如何发挥重要作用。
