Who Receives Intervention for CVI?
While identification begins as a medical issue, it becomes an educational issue since many undiagnosed children are not receiving interventions tailored to their needs, and these children can flounder in the schools without appropriate remediation. To this end, we must consider the following:
Identify children who show normal or mild disorders of visual acuity or visual field but manifest dysfunction of higher order visual systems
Some children may show normal or mild signs of visual impairment based upon visual acuity or visual field limitations, but may manifest visual perceptual or other problems that need to be identified and addressed in educational programs (Downie, Jacobson, Frisk, and Ushensky, 2003; Fazzi et al, 2004; Stiers, De Cock, Vandenbussche, 1998; Dutton et al., 1996; Jacobson et al. 1996). Jacobson and Dutton (2000), for example, indicate that diagnosis can be a challenge for milder forms of PVL [periventricular leucomalacia], especially when children have no cerebral palsy and show normal verbal development. In educational settings, these higher functioning children may be the least understood and the most underserved.
Examine children with CVI for ocular conditions in order to develop comprehensive intervention strategies
Conversely, it is important to identify ocular conditions in children with cortical visual impairment in order to develop optimal intervention approaches (Hard, Aring, & Hellstrom, 2004; Dutton, 2003; Stiers, De Cock, & Vandenbussche, 1999; Stiers et al, 2001). In children with severe motor delays or cognitive impairments, especially, ocular conditions may be overlooked due to difficulty in testing or unawareness of the need for this type of examination.
Consider the presence of brain injury in children with anterior visual pathway disorders leading to visual impairment
One study (Dale & Sonksen, 2002) found that 51 percent of 79 children with congenital anterior visual pathway disorders who were not expected to have central nervous system involvement had brain lesions determined by neuro-imaging techniques. Another (Gronqvist et al, 2001) found that 75 percent of 45 children born at full term with visual impairment had cerebral morphological (42 percent) and/or cerebral functional abnormalities (65 percent) [There is overlap of the two groups.] It will be important to determine if these neurological anomalies are benign in their effect or contribute to more subtle or not-so-subtle behavioral differences that affect function and may benefit from educational remediation techniques.
Develop collaborative diagnostic guidelines for assessment of CVI
Assessment of children with CVI to determine educational interventions needs to be collaborative in nature due to the variety of injuries that present and their complex functional consequences. Collaboration and communication among a variety of specialists are vital for effective assessment of children with complex conditions such as CVI. To provide guidelines for collaboration among these specialists that also include family input would be extremely useful.
Develop systems and accepted methodologies to identify children early
Early recognition of CVI is thought to promote the habilitation process (Dutton & Jacobson, 2001; Good et al., 2001). Systems must be developed and methodologies determined to screen and identify for CVI. Assessment material related to CVI need to have rigorous standardization protocols valid for children with visual impairments. There needs to be some way for teachers and families of children who present behavioral signs of CVI, including higher functioning children, to work with the medical community to diagnose the condition, and perhaps in the not too distant future, to pinpoint the neurological and behavioral correlates.
Note: The above is an excerpt from: Lueck, A. H. (2006). Issues in intervention for children with visual impairment or visual dysfunction due to brain injury. In E. Dennison & A. H. Lueck (Eds.). Proceedings of the Summit on Cerebral/Cortical Visual Impairment: Educational, Family, and Medical Perspectives, April 30, 2005. New York: AFB Press. pp. 121-130. Visit the AFB Press Online Bookstore to purchase a copy of this publication.
Dale, N., & Sonkson, P, (2002). Visual impairment in infancy: Impact on neurodevelopmental and neurobiological processes. Developmental Medicine & Child Neurology, 44, 613-622.
Downie, A. L. S., Jacobson, L.S., Frisk, V., Ushycky, I. (2003). Periventricular brain injury, visual motion processing, and reading and spelling abilities in children who were extremely low birth weight. Journal of International Neuropsychological Society, 9, 440-449.
Dutton, G. N. (2003). Cognitive vision, its disorders, and differential diagnosis in adults and children: knowing where and what things are. Eye, 17, 289-304.
Dutton, G., Ballantyne, J., Boyd, G., Bradman, M., Day, R., McCullough, D., Mackie, R., Philips, S., & Saunders, K. (1996). Cortical visual dysfunction in children: A clinical study. Eye, 10, 302-309.
Dutton, G. N., & Jacobson, L. K. (2001). Cerebral visual impairment in children. Seminars in Neonatology, 6, 47-485
Fazzi, E., Bova, S. M., Uggetti, C., Signorini, S. G., Bianchi, P. E., Maraucci, I., Zoppello, M., & Lanzi, G. (2004). Visual-perceptual impairment in children with periventricular leukomalacia. Brain & Development, 26, 506-512.
Good, W. V., Jan, J.E., Burden, S. K., Skoczenski, A., Candy, R. (2001). Recent advances in cortical visual impairment. Developmental Medicine & Child Neurology, 43, 56-60.
Gronqvist, S., Flodmark, O., Tornqvist, K., Edlund, G., & Hellstrom, A. (2001). Association between visual impairment and functional and morphological cerebral abnormalities in full-term children. Acta Ophthalmolgica Scandinavia, 79, 140-146.
Hard, A.L., Aring, E., & Hellstrom, A. (2004). Subnormal visual perception in school-aged ex-preterm patients in a pediatric eye clinic. Eye, 18, 628-634.
Jacobson, L.K., Dutton, G.N. (2000). Periventricular Leukomalacia: An important cause of visual and ocular motility dysfunction in children. Survey of Ophthalmology, 45(1), 1-13.
Jacobson, L., Ek, U., Fernell, E., Flodmark, O., & Broberger, U. (1996). Visual impairment in preterm children with periventricular leukomalacia—Visual, cognitive, and neuropaediatric characteristics related to cerebral imaging. Developmental Medicine and Child Neurology, 38, 724-735.
Stiers, P. deCock, P., & Vandenbussche, E. (1999). Separating visual perception and non-verbal intelligence in children with early brain injury. Brain & Development, 21(1), 397-406.
Stiers, P., van den Hout, B.M., Haers, Vanderkelen, R., de Vries, L.S., van Nieuwenhuizen, O., & Vandenbussche, E. (2001). The variety of visual perceptual impairments in pre-school children with perinatal brain damage. Brain & Development, 23(1), 333-348.
Van den Hout, B/M., de Vries, L., Meiners, L.C., Stiers, P., van der Schouw, Jennekens-Schinkel, A., Wittebol-Post, D., van der Linde, D., Vandenbussche, E., van Nieuwenhuizen, O. (2004). Visual perceptual impairment in children at 5 years of age with perinatal hemorrhagic or ischaemic brain damage in relation to cerebral magnetic imaging. Brain & Development, 26(1), 251-261.