The Low Vision Exam: Integrating a Functional Approach

Thinking of the low vision evaluation as an extension of the comprehensive eye examination may make it more accessible to providers and patients.

By Grace Tran, OD

The art and practice of low vision rehabilitation can consist of many approaches.1,2 The foundation of the examination for low vision rehabilitation is not at all different from a primary eye care examination. Tests performed during any type of eye examination are used to evaluate a patient’s visual ability/demand and the function of their vision, and they reveal strategies to maximize a patient’s overall quality of life.

The goal of vision rehabilitation is to find ways to use patients’ remaining vision to help them restore or maintain functional ability in their lives.3 Patients with any level of visual impairment can benefit from low vision rehabilitation.2 The way information may be gathered and how the information is used to care for a patient with visual impairment requires a functional approach.4 Just like a primary eye care examination, a vision rehabilitation evaluation will be specific to the patient’s needs and should include a case history, entrance and ancillary tests, refraction, ocular health check, discussion of recommendations, counseling and patient education, and short- and long-term plans for his or her care. Using a functional approach to care for a low vision patient similar to that used during the primary eye care examination may reveal that many of these strategies and tests are already familiar to optometrists.

THE EVALUATION

Following are some tips for sequencing an evaluation with a functional approach to care.

  • Observe the patient. A plethora of information can be gathered by observing the patient throughout the entire examination. Take note of the patient’s mobility, family/social interactions (if applicable), and his or her habitual adaptations while testing.
  • Take a detailed case history that includes how the patient is functioning with his or her vision in all aspects of daily life. Do not be afraid to ask closed-ended questions and tap into the specifics about what the patient is finding difficult. Think about his or her visual demand for each task: does the task require distance, intermediate, and/or near vision? More importantly, find out what the patient has already done to adapt to his or her difficulties.
  • Make a game plan for the examination and share this with the patient before moving forward with testing. After revealing so much about him- or herself, it is helpful to ensure that the patient is comfortable.
  • Entrance testing. The workup and sequence of testing will provide clues as to the patient’s remaining visual ability, as well as reveal any compensatory mechanisms a patient may employ to cope with any deficiencies in vision. See Entrance Testing for Low Vision Assessment for a discussion of some fundamental principles in directing entrance testing.
  • Refraction series (automatic/manual keratometry, retinoscopy, and subjective refraction). A careful refraction is critical to rule out other potential causes of visual impairment.5 Trial frame refraction will provide better answers for patients who are using eccentric viewing6 and/or have visual field issues.
  • Binocular workup. Do not overlook this even though the patient may have reduced visual acuity or ability. Modify the target size and color for testing if needed. Some patients may have a longstanding binocular issue that predates the impairment of their vision that can still be troubling to their visual function. In addition, determining eye dominance, fusion, and binocularity will assist in training tool recommendations.
  • Categorize the presentation/discussion of solutions for the patient based on the priority of his or her goals and visual demand of each goal. Prioritize and tailor recommendations to the patient’s goals, and address one thing at a time. Solutions presented can be in the form of nonoptical, tactile, auditory, and optical tools. Do not forget to address any difficulty with safety, balance, and navigation.
  • Refrain from shining lights into a patient’s eyes until the end of the examination. Some patients have a hard time with adaptation. An ocular health evaluation is necessary to determine the nature and stability of the ocular pathology or disorder.1
  • Additional ancillary/diagnostic tests such as visual field, imaging, and electrodiagnostic testing should be ordered if needed. Prepare the patient, if possible, about what to expect to ease any fear or uncertainty.
  • Take a team approach to care by referring to appropriate providers, and share thoughts with the patient’s referring provider. Reviewing all aspects of the patient’s life and how his or her function may be affected due to visual impairment can reveal ways that other team members can contribute to the patient’s care.7
  • Provide a short- and long-term management plan. Do not be afraid to break up the examination time. Overextending the patient can be tiring and unproductive for both the patient and clinician.
  • Spend time on counseling and patients’ education. Empower patients with knowledge and support them in taking ownership to participate in their own care. Answer any questions the patient may have and help him or her stay positive during the rehabilitation/habilitation process.

CONCLUSION

The foundation of the evaluation for low vision rehabilitation is simply an extended comprehensive primary eye care examination. One approach to practice discussed in this article is the careful sequencing and mild modification to the primary eye care examination. Overall, the value and understanding of vision rehabilitation can be used in daily practice for any patient that has an issue functioning with his or her vision.

Grace Tran, OD, is a staff optometrist and residency program co-coordinator at Veterans Affairs Long Beach Healthcare System, Long Beach, California, and adjunct clinical assistant professor at Southern California College of Optometry, Fullerton, California. Dr. Tran may be reached at grace.tran@va.gov.

  1. Brilliant RL. Essentials of Low Vision Practice. Woburn, MA: Butterworth-Heinemann; 1999.
  2. O’Connor PM, Lamoureux EL, Keeffe JE. Predicting the need for low vision rehabilitation services. Br J Ophthalmol. 2008;92:252-255.
  3. American Optometric Association Clinical Practice Guidelines: Care of the Patient with Vision Impairment, 2007. www.aoa.org/documents/CPG-14.pdf. Accessed April 15, 2013.
  4. Rosenthal BP. The Function-Based Low Vision Evaluation. In: Rosenthal BP, Cole RG, eds. Functional Assessment of Low Vision. St. Louis MO: Mosby; 1996:1-25.
  5. Sunness JS, El Annan J. Improvement of visual acuity by refraction in a low-vision population. Ophthalmology. 2010;117(7):1442-1446.
  6. Lundström L, Gustafsson J, Unsbo P. Vision evaluation of eccentric refractive correction. Optom Vis Sci. 2007;84(11):1046-1052.
  7. Wang BZ, Pesudovs K, Miriam C. Keane MC, et al. Evaluating the effectiveness of multidisciplinary low-vision rehabilitation. Optom Vis Sci. 2012;89:1399-1408.