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Diplopia and Quality of Life
Letters to the Editor Research Correspondence Diplopia and Quality of Life Dear Editor: Diplopia is a common problem in neuro-ophthalmic practice. Most of these patients have strabismus and diminished visual quality of life (QOL),1 but diplopic symptoms are rarely quantified and, thus, difficult to follow objectively over time. The cervical range of motion (CROM) method2,3 permits measurement of diplopia itself rather than strabismus. Diplopia qualitatively reduces QOL. We sought to assess how different amounts of diplopia (by the CROM method) affect visual QOL in adult patients and secondarily the ease and reproducibility this technique in assessing diplopic function. We evaluated 17 adult subjects with diplopia of any etiology using the CROM device (Table 1, available at http://aaojournal.org). Two independent examiners recorded the presence of diplopia in all positions of gaze while the patient viewed a 20/60 Snellen “E”. The area of single binocular vision (SBV) was plotted on a modified Goldmann perimeter chart and analyzed quantitatively using Image J software. A sliding scale modification factor (1 for SBV in primary gaze, decreasing to 0.35 at 30 degrees or more from primary position) based on the method of Sullivan et al4 was used to account for increasing disability with diplopia nearer to fixation. A diplopia score was also calculated.2 Results were averaged for data analysis, and interrater correlations were calculated. Visual acuity and stereopsis at distance (INNOVA Systems, Inc, Burr Ridge, IL) and at near were measured. Subjects completed 2 visual QOL assessments: the NEI VFQ-25 with the 14 question addendum, and the AS-20 (Adult Strabismus Questionnaire, developed to assess the impact of strabismus on a patient’s health-related QOL).5 Nonparametric correlations between diplopia measurements (diplopia score and modified SBV area) and the QOL surveys were calculated using PASW Statistics version 18 for MacIntosh (SPSS, Inc., Chicago, IL), as were interrater correlations for the diplopia score and modified SBV area. A strong correlation between the modified SBV area and the diplopia score (R ⫽ ⫺0.892; P⬍0.0001) was found. Interrater correlation for the diplopia score calculation was excellent (R ⫽ 0.96; range, 0.95– 0.99); the modified SBV field showed more variability (R ⫽ 0.78; range, 0.65– 0.89) that occurred because of variability past 15 degrees eccentric to primary position. There was a negative correlation between the diplopia score and both the AS-20 psychosocial subscale (R ⫽ ⫺0.581; P ⫽ 0.023) (Fig 1A, available at http://aaojournal. org) and the VFQ-25 color (Fig 2A, available at http:// aaojournal.org) and peripheral vision (Fig 2B, available at http://aaojournal.org) subscales (R ⫽ ⫺0.638; P ⫽ 0.01; R ⫽ ⫺0.508; P ⫽ 0.05). The diplopia score did not correlate with the AS-20 functional subscale (Fig 1B, available at
http://aaojournal.org). The modified SBV area had a similar but less strong correlation (in the opposite direction, since diplopia score and SBV area are inverse measures) with AS-20 questionnaire (R ⫽ 0.33, P ⫽ 0.22 for psychosocial and R ⫽ 0.22, P ⫽ 0.43 for functional). No meaningful correlation between distance or near stereopsis and visual QOL was found. There was also no correlation between visual QOL and the magnitude of the strabismic deviation in primary and/or the reading position as measured by prism and cover testing. We find that diplopia measured quantitatively has a linear correlation with worsening psychosocial and perceived peripheral vision measures. A similar quantitative relationship between QOL and degree of strabismus does not exist.1 The CROM-derived diplopia score and SBV area mapping were reproducible between examiners and could be performed with little training of personnel. Our finding that psychosocial but not functional QOL is diminished in relationship to the amount of measured diplopia (the diplopia score) runs counter to expectations. Several of the study participants had diplopia for weeks or months before testing; we postulate that the subjects had adapted to their diplopia and answered the functional questions to reflect this fact. However, their psychosocial well-being was still impacted, and this impact was more severe as the area of single binocular vision (inverse of the diplopia score) became smaller. None of the patients had a perimetric visual field defect, yet there was a strong correlation between higher diplopia scores and worse peripheral vision QOL. It is unclear whether this perception should be classified as functional or psychosocial (since it does not indicate a physiological defect). Future goals include longitudinal studies of diplopic subjects and changes in QOL as their disease evolves. WEN YING WU-CHEN, MD ALEXANDER CHRISTOFF, CO, COT PREM S. SUBRAMANIAN, MD, PHD Baltimore, Maryland ERIC R. EGGENBERGER, DO, MSEPI East Lansing, Michigan References 1. Hatt SR, Leske DA, Kirgis PA, et al. The effects of strabismus on quality of life in adults. Am J Ophthalmol 2007;144:643–7. 2. Holmes JM, Leske DA, Kupersmith MJ. New methods for quantifying diplopia. Ophthalmology 2005;112:2035–9. 3. Kushner BJ. The usefulness of the cervical range of motion device in the ocular motility examination. Arch Ophthalmol 2000;118:946 –50. 4. Sullivan TJ, Kraft SP, Burack C, O’Reilly C. A functional scoring method for the field of binocular single vision. Ophthalmology 1992;99:575– 81. 5. Hatt SR, Leske DA, Bradley EA, et al. Development of a quality-of-life questionnaire for adults with strabismus. Ophthalmology 2009;116:139 – 44.e5.
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Ophthalmology Volume 118, Number 7, July 2011 Table. Subject Demographics Patient Characteristics
Value (range)
Average age (yrs) Sex (M:F) Cause of diplopia -thyroid eye disease -CN III palsy -CN IV palsy -CN VI palsy -Combined CN IV, VI palsy -divergence insufficiency -post-traumatic (orbital fracture)
52.2 (39–80) 10:7 6 1 2 4 1 2 1
Figure 1. Correlation of psychosocial (A) and functional (B) visual quality of life (QOL) domains with diplopia score. A strong negative correlation (R ⫽ ⫺0.581, P ⫽ 0.023) was observed between the psychosocial QOL and diplopia score, while no significant diplopia score relationship was seen with functional QOL (R ⫽ ⫺0.155, P ⫽ 0.55).
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Figure 2. Diplopia score relationship to VFQ-25 subdomains. Only the 2 domains with significant results (color vision and peripheral vision) are presented. Scores below 100 are abnormal. A, For the color vision subdomain, a negative correlation between the diplopia score and self-rating on this scale is seen; R ⫽ ⫺0.638, P ⫽ 0.01. B, Scores for peripheral vision decreased with worsening (increasing) diplopia scores; R ⫽ ⫺0.508, P⫽0.05.
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http://aaojournal.org). The modified SBV area had a similar but less strong correlation (in the opposite direction, since diplopia score and SBV area are inverse measures) with AS-20 questionnaire (R ⫽ 0.33, P ⫽ 0.22 for psychosocial and R ⫽ 0.22, P ⫽ 0.43 for functional). No meaningful correlation between distance or near stereopsis and visual QOL was found. There was also no correlation between visual QOL and the magnitude of the strabismic deviation in primary and/or the reading position as measured by prism and cover testing. We find that diplopia measured quantitatively has a linear correlation with worsening psychosocial and perceived peripheral vision measures. A similar quantitative relationship between QOL and degree of strabismus does not exist.1 The CROM-derived diplopia score and SBV area mapping were reproducible between examiners and could be performed with little training of personnel. Our finding that psychosocial but not functional QOL is diminished in relationship to the amount of measured diplopia (the diplopia score) runs counter to expectations. Several of the study participants had diplopia for weeks or months before testing; we postulate that the subjects had adapted to their diplopia and answered the functional questions to reflect this fact. However, their psychosocial well-being was still impacted, and this impact was more severe as the area of single binocular vision (inverse of the diplopia score) became smaller. None of the patients had a perimetric visual field defect, yet there was a strong correlation between higher diplopia scores and worse peripheral vision QOL. It is unclear whether this perception should be classified as functional or psychosocial (since it does not indicate a physiological defect). Future goals include longitudinal studies of diplopic subjects and changes in QOL as their disease evolves. WEN YING WU-CHEN, MD ALEXANDER CHRISTOFF, CO, COT PREM S. SUBRAMANIAN, MD, PHD Baltimore, Maryland ERIC R. EGGENBERGER, DO, MSEPI East Lansing, Michigan References 1. Hatt SR, Leske DA, Kirgis PA, et al. The effects of strabismus on quality of life in adults. Am J Ophthalmol 2007;144:643–7. 2. Holmes JM, Leske DA, Kupersmith MJ. New methods for quantifying diplopia. Ophthalmology 2005;112:2035–9. 3. Kushner BJ. The usefulness of the cervical range of motion device in the ocular motility examination. Arch Ophthalmol 2000;118:946 –50. 4. Sullivan TJ, Kraft SP, Burack C, O’Reilly C. A functional scoring method for the field of binocular single vision. Ophthalmology 1992;99:575– 81. 5. Hatt SR, Leske DA, Bradley EA, et al. Development of a quality-of-life questionnaire for adults with strabismus. Ophthalmology 2009;116:139 – 44.e5.
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Ophthalmology Volume 118, Number 7, July 2011 Table. Subject Demographics Patient Characteristics
Value (range)
Average age (yrs) Sex (M:F) Cause of diplopia -thyroid eye disease -CN III palsy -CN IV palsy -CN VI palsy -Combined CN IV, VI palsy -divergence insufficiency -post-traumatic (orbital fracture)
52.2 (39–80) 10:7 6 1 2 4 1 2 1
Figure 1. Correlation of psychosocial (A) and functional (B) visual quality of life (QOL) domains with diplopia score. A strong negative correlation (R ⫽ ⫺0.581, P ⫽ 0.023) was observed between the psychosocial QOL and diplopia score, while no significant diplopia score relationship was seen with functional QOL (R ⫽ ⫺0.155, P ⫽ 0.55).
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Figure 2. Diplopia score relationship to VFQ-25 subdomains. Only the 2 domains with significant results (color vision and peripheral vision) are presented. Scores below 100 are abnormal. A, For the color vision subdomain, a negative correlation between the diplopia score and self-rating on this scale is seen; R ⫽ ⫺0.638, P ⫽ 0.01. B, Scores for peripheral vision decreased with worsening (increasing) diplopia scores; R ⫽ ⫺0.508, P⫽0.05.
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