Secondary Logo

Journal Logo

Dyschromatopsia in Multiple Sclerosis Patients: A Marker of Subclinical Involvement? Response

Felgueiras, Helena MD; Parra, Joana MD; Cruz, Simão MD; Pereira, Pedro MD; Santos, Ana F. MD; Rua, Adriana MD; Meira, Dália MD; Fonseca, Pedro MD; Pedrosa, Catarina MD; Cardoso, João N. MD; Almeida, Cristina MD; Araújo, Maria MD; Santos, Ernestina MD

Journal of Neuro-Ophthalmology: March 2017 - Volume 37 - Issue 1 - p 108–109
doi: 10.1097/WNO.0000000000000486
Letters to the Editor
Free

Neurology Department, Centro Hospitalar de Vila Nova de Gaia/Espinho, Vila Nova de Gaia, Portugal

Neurology Department, Centro Hospitalar e Universitário de Coimbra, Coimbra, Portugal

Neurology Department, Hospital Fernando Fonseca, Lisboa, Portugal

Neurology Department, Hospital Garcia de Orta, Almada, Portugal

Neurology Department, Hospital de Braga, Braga, Portugal

Neurology Department, Centro Hospitalar do Porto, Porto, Portugal

Ophthalmology Department, Centro Hospitalar de Vila Nova de Gaia/Espinho, Vila Nova de Gaia, Portugal

Ophthalmology Department, Centro Hospitalar e Universitário de Coimbra, Coimbra, Portugal

Ophthalmology Department, Hospital Fernando Fonseca, Lisboa, Portugal

Ophthalmology Department, Hospital Garcia de Orta, Almada, Portugal

Ophthalmology Department, Hospital de Braga, Braga, Portugal

Ophthalmology Department, Centro Hospitalar do Porto, Porto, Portugal

Neurology Department, Centro Hospitalar do Porto, Porto, Portugal

Instituto de Ciências Biomédicas de Abel Salazar da Universidade do Porto, Porto, Portugal

The authors report no conflicts of interest.

We thank Dr. Subramanian and colleagues for their critical appraisal and interest in our article (1). They suggested that Hardy–Rand–Rittler (HRR) pseudoisochromatic plates are not a sensitive indicator of acquired color vision deficits in patients with optic neuropathies. While we agree that a hue discrimination test such as the Farnsworth-Munsell (FM) 100 hue test is more sensitive than HRR plate testing, we chose the latter given the fact that it is widely available and easy to perform (2). Moreover, several studies have shown that HRR plates are an effective test of color vision as long as visual acuity is better than 20/50 (3). Use of HRR plates, when compared with the FM 100 hue test, is easier and quicker to perform, and almost all normal subjects would likely make no errors, while in the FM 100 hue test normal subjects would make a few mistakes (2). Zhao et al (4) also bring up an interesting hypothesis that HRR plate testing may be used to screen patients with multiple sclerosis for deficits in contrast sensitivity. One limitation of our study is that contrast sensitivity was not assessed. We look forward to future studies to further address this issue.

Back to Top | Article Outline

REFERENCES

1. Felgueiras H, Parra J, Cruz S, Pereira P, Santos AF, Rua A, Meira D, Fonseca P, Pedrosa C, Cardoso JN, Almeida C, Araújo M, Santos E. Dyschromatopsia in multiple sclerosis patients: a marker of subclinical involvement? J Neuroophthalmol. 2016;36:275–279.
2. Foote KG, Neitz M, Neitz J. Comparison of the Richmond HRR 4th edition and Farnsworth-Munsell 100 Hue Test for quantitative assessment of tritan color deficiencies. J Opt Soc Am A Opt Image Sci Vis. 2014;31:A186–A188.
3. Ng JS, Shih B. Level of visual acuity necessary to avoid false-positives on the HRR and Ishihara color vision tests. Eur J Ophthalmol. [published ahead of print September 7, 2016] doi: .
4. Zhao J, Davé SB, Wang J, Subramanian PS. Clinical color vision testing and correlation with visual function. Am J Ophthalmol. 2015;160:547–552.e1.
© 2017 by North American Neuro-Ophthalmology Society