Dienke Wittebol-Post

THE PREVALENCE OF CEREBRAL VISUAL DISTURBANCE IN CHILDREN WITH CEREBRAL PALSY

Assessment of visual acuity using the visual acuity card procedure in 164 children with cerebral palsy revealed low visual acuity in 71 per cent. Results of ophthalmological examination were available for 74 of these patients, but could not explain adequately the low visual acuity of 36 of the 43 patients (84 per cent) assessed by both the acuity card procedure and other techniques. There is a high probability that cerebral visual disturbance is present in these patients. Awareness of visual disability when compiling a programme of visual and neurodevelopmental stimulation for children with cerebral palsy is essential.

Ophthalmological Aspects of Pierson Syndrome

PURPOSE To study the ocular phenotype of Pierson syndrome and to increase awareness among ophthalmologists of the diagnostic features of this condition. DESIGN Retrospective, observational case series. METHODS A multicenter study of 17 patients with molecularly confirmed Pierson syndrome. The eye findings were reviewed and compared to pertinent findings from the literature. RESULTS The most characteristic ocular anomaly was microcoria. A wide range of additional abnormalities were found, including posterior embryotoxon, megalocornea, iris hypoplasia, cataract, abnormal lens shape, posterior lenticonus, persistent fetal vasculature, retinal detachment, variable axial lengths, and glaucoma. There was high interocular and intrafamilial variability. CONCLUSIONS Loss-of-function mutations in laminin beta2 (LAMB2) cause a broad range of ocular pathology, emphasizing the importance of laminin beta2 in eye development. Patients with Pierson syndrome can initially present with ocular signs alone. In newborns with marked bilateral microcoria, Pierson syndrome should be considered and renal function investigated.

Visual perceptual impairment in children at 5 years of age with perinatal haemorrhagic or ischaemic brain damage in relation to cerebral magnetic resonance imaging

Children with perinatally acquired parenchymal haemorrhage are thought to have better visual perceptual skills than those with leukomalacia. We examined seven prematurely born children with parenchymal haemorrhage and 14 with grades 2-4 leukomalacia, at the age of 5 years. Clinical and magnetic resonance imaging parameters were related to visual perceptual performance assessed with the L94, using performance age. Belonging to the leukomalacia group, the inability to walk, a diminished peritrigonal white matter, a high degree of gliosis and cortical damage were associated with poorer visuo-perceptual skills. Enlarged lateral ventricles, confirming the findings of Melhelm (Radiology 214 (2000) 199), were associated with both cognitive, perceptual and motor problems and probably reflect the considerable extent of the brain damage. Specific factors protecting against visual perceptual impairment were a preserved volume of the right optical radiation and of the splenium of the corpus callosum. Children with leukomalacia are at considerable risk of visual perceptual impairment. Children with right-sided parenchymal haemorrhages also appear to be at risk although they function much better due to better motor and cognitive skills.

Role of visual dysfunction in postural control in children with cerebral palsy.

Introduction: Deficient postural control is one of the key problems in cerebral palsy (CP). Little, however, is known about the specific nature of postural problems of children with CP, nor of the relation between abnormal posture and dysfunction of the visual system. Aim of the study: To provide additional information on the association of abnormalities in postural control and visual dysfunction of the anterior or posterior part of the visual system. Methods: Data resulting from ophthalmologic, orthoptic, neurological, neuro-radiological, and ethological investigations of more than 313 neurologically impaired children were retrospectively analyzed. Results: Abnormal postural control related to ocular and ocular motor disorders consisted of anomalous head control and subsequent abnormal head posture and torticollis. The abnormal postural control related to retrochiasmatical damage of the visual system consisted of a torticollis combined with adjustment of the upper part of the body, as if at the same time adapting to a combination of defects and optimizing residual visual functions. Conclusion: Visual dysfunctions play a distinct role in the postural control of children with CP.

Visual behaviours of neurologically impaired children with cerebral visual impairment: an ethological study

BACKGROUND/AIMS Visual functions of neurologically impaired children with permanent cerebral visual impairment (CVI) can be difficult to determine. This study investigated the behavioural profile of CVI children by means of ethological observations in order to gain a better understanding of their visual functions. METHODS Video registrations of nine subjects who were unable to undergo more orthodox methods of visual function testing were observed and analysed by an ethologist. RESULTS A series of behaviours (direct signs) and supportive or confirming behavioural elements (indirect signs) indicating some visual perception in the children were found. CONCLUSION Detailed ethological observations of visual behaviour were shown to be useful for analysing visual functions of children with permanent CVI.

Development of visual function in hemihydranencephaly

This study reports on the findings of longitudinal follow‐up of visual function in a 12‐year‐old girl affected by congenital right hemihydranencephaly. This extremely rare unilateral brain malformation allowed the authors to gather new information on neuronal plasticity and functional compensations of the visual system across a period of 10 years. An extension of the preserved right visual hemifields above the middle line and strategical eye or head positions developed to increase visual functions are discussed. In addition, ophthalmological and orthoptical findings, as well as the development of monocular grating and linear acuity, are described.

Epilepsy surgery provides new insights in retinotopic organization of optic radiations. A systematic review.

Purpose of review Visual field defects (VFDs) produced by temporal lobe resections provide valuable information on the retinotopic organization of the optic radiations. The results of this systematic review of the literature will be translated into a revised – and evidence-based – map of the retinotopic anatomy of the anterior optic radiations. Recent findings Recent studies provide best evidence by combining automatic static perimetry and modern imaging techniques. VFDs occur in 83% of patients undergoing temporal lobectomy. There is a significant correlation between size of resection and amount of VFD. Most defects appear incongruous. Macular involvement is seen in more than 50% of cases. The inferolateral defect border is of a sloping nature and sometimes crosses the horizontal meridian. On the basis of these findings, the classical theory on the retinotopic anatomy of the optic radiation should be revised. Summary This article systematically reviews the literature on VFDs after temporal lobe resection. Frequency, size, congruity, macular involvement and defect borders are related to size of resection. The classical theory on the retinotopic organization of the anterior optic radiations should be revised.

Longitudinal follow-up of grating acuity in children affected by cerebral palsy: Results of a 5 year study

Purpose To analyse the natural course of visual acuity in subjects affected by cerebral palsy.Methods During the past 5 years, 16 children underwent repeated grating acuity measurements using the acuity card procedure. At the end of the follow-up final grating acuity was compared with linear acuity obtained using standard optotypes.Results A good or moderate improvement in grating acuity was shown by 14 subjects. However, the general development of grating acuity showed a protracted course and early values did not correlate with final grating acuity (r = 0.20). Moreover, most of the children showed subnormal vision when measured with standard optotypes.Conclusion Clinicians should remain optimistic about the potential for some visual development in children affected by cerebral palsy. However, great caution should be exercised in extrapolating information from early grating acuity measurements. Regular assessments with the acuity card procedure are necessary in order to gain an insight into the natural course of visual development in children affected by cerebral palsy.

Cleft lip and cone-rod dystrophy in a consanguineous sibship.

Three siblings from a consanguineous marriage were found to have a cleft lip. Two of them developed a progressive retinopathy which was identified as a cone-rod dystrophy. It is suggested that this association may represent a hitherto unreported entity with an autosomal recessive pattern of inheritance. Although chance co-occurrence cannot be excluded.

A child with a peculiar nystagmus

A seven-month old girl developed a peculiar asymmetrical pendular nystagmus after varicella infection, suggesting neurological disease. No neuro-ophthalmological signs were found. Neuro-imaging, however, revealed an unexpectedly large chiasmal tumor.