Glaucoma: the patient's perspective

Ananth Viswanathan

The conventional view

• Glaucoma is often described as 'the silent thief of sight'.
• This presupposes that patients are not aware of any visual problems until the end stage.

The conventional view is WRONG

• There is ample evidence^1,2,3 that patients are aware of problems despite relatively minor binocular field loss.
• A patient who notices gradual visual deterioration is twice as likely to have bilateral field progression as not.³
• In order to forge a closer link between standard clinical tests and patient perception, we need to estimate the binocular visual field.
• This begs the question:

Is it possible to merge bilateral monocular field tests to predict the binocular field?

• Yes.
• Several studies^4,5,6 have shown that the Integrated Visual Field (predictions based on the highest sensitivity between eyes at each visual field test location) predicts the binocular field accurately.
• The Integrated Visual Field is more closely linked to patient perception than formal Esterman testing^.6,7
• The Integrated Visual Field test agrees well with the current method (Esterman) of classifying visual fields with regard to legal fitness to drive in the United Kingdom in patients with
  glaucoma; it appears superior to the current method in identifying those with reduced fitness to drive.⁸

References

1. Nelson P, Aspinall P, Papasouliotis O, Worton B, O'Brien C. Quality of life in glaucoma and its relationship with visual function. J Glaucoma 2003; 12: 139-150.
2. Noe G, Ferraro J, Lamoureux E, Rait J, Keeffe JE. Associations between glaucomatous visual field loss and participation in activities of daily living. Clin Experiment Ophthalmol 2003; 31: 482-486.
3. Viswanathan AC, McNaught AI, Poinoosawmy D, Fontana L, Crabb DP, Fitzke FW, et al. Severity and stability of glaucoma: patient perception compared with objective measurement. Arch Ophthalmol 1999; 117: 450-454.
4. Crabb DP, Viswanathan AC, McNaught AI, Poinoosawmy D, Fitzke FW, Hitchings RA. Simulating binocular field status in glaucoma. Br J Ophthalmol 1998; 82: 1236-1241.
5. Nelson-Quigg JM, Cello K, Johnson CA. Predicting binocular visual field sensitivity from monocular visual field results. Invest Ophthalmol Vis Sci 2000; 41: 2212-2221.
6. Jampel HD, Friedman DS, Quigley H, Miller R. Correlation of the binocular visual field with patient assessment of vision. Invest Ophthalmol Vis Sci 2002; 43: 1059-1067.
7. Crabb DP, Viswanathan AC. Integrated visual fields: a new approach to measuring the binocular field of view and visual disability. Graefes Arch Clin Exp Ophthalmol 2004.
8. Crabb DP, Fitzke FW, Hitchings RA, Viswanathan AC. A practical approach to measuring the visual field component of fitness to drive. Br J Ophthalmol 2004; 88: 1191-1196.