The Human Touch

Data derived from imaging tools can be helpful for the diagnosis and prognosis of glaucoma, but should only be used as a supplement to and not as a substitute for a competent clinical examination, according to George L Spaeth MD “I am not opposed to the introduction of better technologies, and I have worked towards that goal. But, as physicians and patients increasingly rely on indirect and machine-driven markers of health and disease, I have witnessed the deterioration of physicians’ abilities to take histories, examine patients, and perceive and understand patterns,” said Dr Spaeth, Esposito Research Professor of Ophthalmology, Kimmel Medical College, Jefferson University, Philadelphia, USA. “I believe we need to preserve, teach, and research the skills of direct physical examination. Every step away from data that result from touching the patient – touching physically, emotionally, and spiritually – is a step away from understanding the essence of the patient, engaging the patient in his or her own care, and the promotion of health that is the primary objective of the patient encounter. What we are interested in is what happens to the patient as a result of our examination, and guiding the patient so that he or she can heal himself or herself is what we are really trying to do. What comes out of a machine is only data, and it has no relevance to patient engagement. The development of a relationship between the doctor and the patient is most likely to result in the person being fully engaged in his or her own care,” he said. LIMITATIONS AND STRENGTHS Whether information is obtained using technology or by physical examination, it is critical to consider its accuracy and its relevance to the patient. Accuracy depends in part on the method of obtaining the data. Dr Spaeth noted that there can be accuracy problems with both imaging and clinical examination. For example, physicians may pay no attention to signal strength when reviewing images obtained by optical coherence tomography (OCT). Or, a machine-derived readout can be simply erroneous, as demonstrated by Dr Spaeth’s personal experience where the Disc Damage Likelihood Scale score calculated by a spectral-domain OCT device wrongly indicated he had glaucoma. “Statistically-derived outputs based on population averages may not be applicable to the individual,” he said. Clinical examination can also yield invalid information. For example, optic disc examination is often done without pupil dilation, or physicians performing applanation tonometry may fail to confirm that the mires are properly aligned. When it comes to relevance to the patient, however, clinical examination has the advantage. Relevance is judged against what patients care about most, which is how they feel and function, and those aspects are best ascertained through history and observation. “What we are looking for is whether the data will tell us about quality of life and ability to act,” said Dr Spaeth. Relevant data include the patients’ comments and temporal patterns recorded through personal observation of such things as how patients walk into the examining room, whether they are happy or depressed, and if change in the optic nerve appearance corresponds to a new visual field defect. Measurements that allow accurate prediction of disability development are also important, and the rate of change in the optic disc or visual field are probably most helpful. However, the data still need to be interpreted, and then the interpretations need to be individualised, said Dr Spaeth. QUALITY OF LIFE He illustrated his latter point with findings from studies showing that the relationship between visual acuity and quality of life differs between urban- and rural-dwelling populations, while the impact of visual field loss on function also varies among individuals. A search of the literature identified no studies comparing the accuracy of clinical examination alone with machine- or laboratory-derived data for glaucoma diagnosis or prognosis. However, Dr Spaeth said it did uncover numerous articles consistent with his beliefs about the need for conducting an accurate clinical examination and the fact that too many physicians lack the necessary skills. Resurrection of the necessary skills may be difficult, however, because the personal examination takes time and effort, and habits are hard to change. “It is much easier to look at a coloured labelled printout than at an optic disc, and the course chosen is often that which is economically and/or emotionally more beneficial for the physician than for the patient,” said Dr Spaeth. “So, how are you going to keep someone down on the farm once they have seen Paris? When the data acquisition material is readily available, how can you convince physicians to look at the optic disc? The answer is to make them understand that when they look at the optic disc, the patient is going to do better,” he added. George L Spaeth: gspaeth@willseye.org