Understanding low functioning cerebral visual impairment: An Indian context

Abstract

For several reasons, cerebral visual impairment (CVI) is emerging as a major cause of visual impairment among children in the developing world and we are seeing an increasing number of such children in our clinics. Owing to lack of early training about CVI and it being a habilitation orientated subject, we need to become equipped to optimally help the affected children. In this paper we have explained our pragmatic approach in addressing children who present with low functioning CVI. Initially we explain briefly, how vision is processed in the brain. We then present what should be specifically looked for in these children in regular clinics as a part of their comprehensive ophthalmic examination. We discuss the process of functional vision evaluation that we follow with the help of videos to explain the procedures, examples of how to convey the conclusions to the family, and how to use our findings to develop intervention guidelines for the child. We explain the difference between passive vision stimulation and vision intervention, provide some common interventions that may be applicable to many children and suggest how to infuse interventions in daily routines of children so that they become relevant and meaningful leading to effective learning experiences.

Keywords: Cerebral visual impairment; developing countries; early intervention; functional vision assessment; interdisciplinary management; multisensory training.

Figure 1

Showing the three visual brain areas, and the connecting dorsal, and ventral streams

Figure 2

(a) Lea paddles. (b) Puppet faces. (c) Cloth glove with puppet face on one side and lines pattern on other side. (d) Use of mirror to assess vision. (e) Hiding Heidi test. (f) Clutter and noise free room with facility to position the child for functional vision assessment. (g) Simulation of how enhancing facial contrast by make-up may help a child with low visual acuity and low contrast sensitivity-Face without make-up (left), face with make-up (right) as seen by a child with low acuity and contrast sensitivity. (h) Tent with minimal pattern and single plain colour may help reduce visual distractions

Figure 3

Showing how to choose appropriate toy as per thresholds of vision: (a) Toy on the left is very attractive but not suitable for a child with profound CVI, but (b) the toy on right would be more appropriate