Pre-cataract surgery: To operate or not to operate?

A 38-year-old female patient presented with a dense cortical lens opacity in the left eye of congenital origin. Her best corrected visual acuity was 0.4 logMAR and she was to be assessed as whether suitable for cataract extraction.

Microperimetry

A non-mydriatic confocal microperimetry assessment was performed using the MAIA device (Figure 1, Haag-Streit UK). Even though cataract partially affects the quality of the scanning laser ophthalmoscopy image (the blurring of the black and white image in Figure 2), it does not prevent accurate measurement of retinal sensitivity. A suprathreshold test, typically used to screen patients with no known disease, was used in this case. The program measures two levels of sensitivity, resulting in three colour-coded outcomes (27dB = green, 25dB = orange and <25dB = red) corresponding to the normal, suspect and abnormal ranges. The typical duration of this test (37 stimuli) is two minutes per eye. Macular sensitivity appeared to be normal at most locations, as shown in the sensitivity map in Figure 2. Fixation was relatively stable, with the preferred retinal locus (PRL) located in the foveal area, suggesting good foveal function.