• The status of the macula should be included in the preoperative evaluation of patients about to undergo keratoplasty or cataract extraction. Frequently, corneal opacities or cataracts preclude visualization of macular details. In such cases, the Amsler grid is useful in assessing macular function. This study evaluated 15 patients with opaque media. In 13 patients, the opacity was too dense to allow the patient to see the Amsler grid. However, all 13 patients could see the illuminated version of the grid. Of the three abnormal responses detected by use of the illuminated grid, two were caused by macular pathology and one by amblyopia.
Miller D, Lamberts DW, Perry HD. An Illuminated Grid for Macular Testing. Arch Ophthalmol. 1978;96(5):901–902. doi:10.1001/archopht.1978.03910050503025