This prospective study found that glaucoma patients with the most impaired central visual fields or lowest contrast sensitivity were more likely to have trouble with face recognition compared with other glaucoma patients and healthy controls.
These results are not surprising. However, this study highlights that glaucoma patients may have more difficulty with facial recognition and this impairment may have socially and psychologically debilitating consequences. Ophthalmologists should be aware of this problem and its implications in caring for their advanced glaucoma patients.
The authors used the Cambridge Face Memory Test to compare the facial recognition ability of 54 glaucomatous patients with that of 41 age-similar visually-healthy controls. Glaucomatous patients were classified into three groups according to the severity of their best-eye visual field (VF) defect (early, moderate, or advanced) using the Hodapp, Parrish and Anderson (HPA) classification, which summarizes the overall extent of damage while also taking into account the proximity of the defect to fixation.
Patients with advanced bilateral 24-2 VF loss identified fewer faces on average (66 percent) than those with early (75 percent) and moderate (75 percent) defects and controls (75 percent; P < 0.05). The same was true for patients with significant 10-2 VF loss, although the effect was slightly less pronounced (67 percent).
The authors write that this weak trend could indicate that while patients with advanced VF loss may be aware of some disability, they may underestimate their true level of task performance impairment. This finding coincides with previous research suggesting that patient perceptions of their vision do not necessarily match with their actual level of functioning.
The authors also note that while there was an obvious shift in performance for more advanced patients, there was still considerable variability in the scores of participants within each severity group. Since the HPA method places some emphasis on central vision defects, it is possible that these defects were influential in determining the observed effects.
Multiple regression analysis revealed that contrast sensitivity was also important for face recognition. The authors write that some studies using different experimental designs disagree that contrast sensitivity is important for face recognition and suggest that loss of visual acuity is more debilitating.
They conclude that face recognition deficits, as a disability, should not be underestimated as they can cause anxiety, embarrassment and the subsequent avoidance of social situations.