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Purpose: To describe the clinical features of a visual variant Alzheimer's disease, a disorder that might be seen by the ophthalmologist with visual symptoms and signs. Design: Retrospective case series. Participants: Eight patients with Alzheimer's disease presenting with predominantly visual complaints. Methods: A retrospective review of patients at a tertiary care academic center seen by the authors from 1999 to 2001 with Alzheimer's disease and predominantly visual complaints. Results: Eight patients with the visual variant of Alzheimer's disease were reviewed. All had seen eye care providers before referral to the neuro-ophthalmology clinic for visual complaints but without a diagnosis. Four patients had homonymous visual field loss, and two had presumed cortical visual impairment. Neuroimaging showed either normal brain (1 patient) or atrophy of the parietal or occipital areas but no structural lesions (7 patients). Fluoro-18-deoxyglucose positron emission tomography scans were performed in five of the cases, and all showed hypoperfusion in the parietooccipital areas. Neuropsychologic testing revealed visuospatial deficits in all 5 patients tested. Conclusions: Visual symptoms might be the presenting (or rarely only) manifestation of Alzheimer's disease. Clinicians should be aware of the visual variant of Alzheimer's disease. Neuropsychological testing and magnetic resonance imaging (MRI) provide supporting evidence for the diagnosis. Positron emission tomography scans might be helpful in selected cases, especially those with a normal MRI.

OBJECTIVE To compare Early Treatment Diabetic Retinopathy Study visual acuity outcome with retinal structural outcome at the 6-year follow-up examination of infants randomized in the Early Treatment for Retinopathy of Prematurity study. METHODS We compared the results in 606 eyes of subjects in whom both functional (visual acuity) and retinal structural assessments were obtained at age 6 years. Visual acuity assessments were performed by masked testers, and retinal examinations were performed by certified ophthalmologists. MAIN OUTCOME MEASURES Visual acuity and retinal structure at age 6 years. RESULTS Concordant outcomes occurred in 462 eyes (76.2%): 402 eyes had favorable functional and structural outcomes and 60 eyes had unfavorable functional and structural outcomes. Discordant outcomes occurred in 92 eyes (15.2%): 86 eyes had unfavorable functional and favorable structural outcomes and 6 eyes had favorable functional and unfavorable structural outcomes. Of the 86 eyes with unfavorable functional and favorable structural outcomes, 43 had optic atrophy (23 eyes) and/or retinal abnormalities that were less severe than those considered to be unfavorable (32 eyes). In 52 eyes (8.6%), retinal structure could not be assessed or the visual acuity was untestable. CONCLUSION Posterior pole appearance correlates well with visual acuity in 6-year-old infants with a history of advanced retinopathy of prematurity. APPLICATION TO CLINICAL PRACTICE When the retinal structure is normal but visual acuity is poor in infants with a history of severe retinopathy of prematurity, other diagnoses such as optic atrophy and cortical visual impairment could at least partially account for the discrepancy. TRIAL REGISTRATION clinicaltrials.gov Identifier: NCT00027222.

This article presents a review of the literature and a case study on a child with cortical visual impairment. The literature review covers the diagnosis, etiology, prevalence, prognosis, and a comparison of the differences between children with cortical visual impairment and those with ocular impairment. The case study presents occupational therapy intervention strategies specific to cortical visual impairment and results of treatment.

Background and Aims Shaken Baby Syndrome (SBS) is a severe form of child abuse caused by violent shaking leading to severe head injuries, causing mild-severe long-term disabilities and death. The study aims to explore medium/long-term consequences of SBS comparing children undergoing neurosurgery with hematoma evacuation/cranioplasty with those with hematoma evacuation or no surgery. Methods A cohort of 21 children with SBS, admitted to Pediatric Department/Padua Hospital (2003–2011), was followed-up. Each clinical record was reviewed collecting information on onset, acute course, ophthalmologic examinations, neuroimaging, treatment and procedures, family history and social background. Cases were followed-up at 3, 6 and 12 months after trauma, every year. The assessment included fundus evaluation and visual function, neuroradiological exams (MRI). Results 21 cases were reviewed (M:F=2:1.1), 12 foreigners, 9 italians. Mean age at onset: 5.7 months (range 1.2–18). Mean age at last follow-up evaluation: 30.4 months (range 5–82). Mean follow-up duration: 24.6 months (range 1–73.5). In acute phase 8/19 underwent neurosurgical intervention and 1/21 underwent eye surgery. 20/21 showed retinal hemorrhages, 21/21 cerebral hemorrhages, 11/21 cerebellar hemorrhages, 5/10 spinal subdural hematoma, 4/21 skull fractures, 6/21 other body region fractures. At last follow-up evaluation resulted: 2/21 hemiplegia, 1/21 paraplegia, 1/21 tetraplegia, 2/21 cortical visual impairment, 3/21 visual field deficits, 4/21 strabismus. 10/21 underwent cognitive and behavioural assessment demostrating in 6 cases global delay and in 4 cases delay in specific functions (locomotor, eye and hand coordination, performance scale). Surgical procedure’s video will be shown. Conclusions SBS may influence child development and therapeutical surgical approach seems crucial.

Fifteen children (most of whom were neurologically multiply disabled) with severe, chronic sleep disorders were treated with 2 to 10mg of oral melatonin, given at bedtime. Nine had fragmented sleep patterns, three had delayed sleep onset and three others had non-specific sleep disturbance of unclear aetiology; all had failed to respond to conventional management. Nine patients had ocular or cortical visual impairment. The health, behavioural and social benefits of treatment were significant, and there were no adverse side-effects. While the response was not always complete, the study clearly showed that melatonin has an important role in the treatment of certain types of chronic sleep disorders.

Childhood blindness has an adverse effect on growth, development, social, and economic opportunities. Severe visual impairment (SVI) and blindness in infants must be detected as early as possible to initiate immediate treatment to prevent deep amblyopia. Although difficult, measurement of visual acuity of an infant is possible. The causes of SVI and blindness may be prenatal, perinatal, and postnatal. Congenital anomalies such as anophthalmos, microphthalmos, coloboma, congenital cataract, infantile glaucoma, and neuro-ophthalmic lesions are causes of impairment present at birth. Ophthalmia neonatorum, retinopathy of prematurity, and cortical visual impairment are acquired during the perinatal period. Leukocoria or white pupillary reflex can be cause by congenital cataract, persistent hyperplastic primary vitreous, or retinoblastoma. While few medical or surgical options are available for congenital anomalies or neuro-ophthalmic disorders, many affected infants can still benefit from low vision aids and rehabilitation. Ideally, surgery for congenital cataracts should occur within the first 4 months of life. Anterior vitrectomy and primary posterior capsulotomy are required, followed by aphakic glasses with secondary intraocular lens implantation at a later date. The treatment of infantile glaucoma is surgery followed by anti-glaucoma medication. Retinopathy of prematurity is a proliferation of the retinal vasculature in response to relative hypoxia in a premature infant. Screening in the first few weeks of life can prevent blindness. Retinoblastoma can be debulked with chemotherapy; however, enucleation may still be required. Neonatologists, pediatricians, traditional birth attendants, nurses, and ophthalmologists should be sensitive to a parent’s complaints of poor vision in an infant and ensure adequate follow-up to determine the cause. If required, evaluation under anesthesia should be performed, which includes funduscopy, refraction, corneal diameter measurement, and measurement of intraocular pressure.

Objective We wanted to investigate the usefulness of event-related (ER) functional MRI (fMRI) for the assessment of cortical visual impairment in infants with periventricular leukomalacia (PVL). Materials and Methods FMRI data were collected from 24 infants who suffered from PVL and from 12 age-matched normal controls. Slow ER fMRI was performed using a 3.0T MR scanner while visual stimuli were being presented. Data analysis was performed using Statistical Parametric Mapping software (SPM2), the SPM toolbox MarsBar was used to analyze the region of interest data, and the time to peak (TTP) of hemodynamic response functions (HRFs) was estimated for the surviving voxels. The number of activated voxels and the TTP values of HRFs were compared. Pearson correlation analysis was performed to compare visual impairment evaluated by using Teller Acuity Cards (TAC) with the number of activated voxels in the occipital lobes in all patients. Results In all 12 control infants, the blood oxygenation level-dependent (BOLD) signal was negative and the maximum response was located in the anterior and superior part of the calcarine fissure, and this might correspond to the anterior region of the primary visual cortex (PVC). In contrast, for the 24 cases of PVL, there were no activated pixels in the PVC in four subjects, small and weak activations in six subjects, deviated activations in seven subjects and both small and deviated activations in three subjects. The number of active voxels in the occipital lobe was significantly correlated with the TAC-evaluated visual impairment (p < 0.001). The mean TTP of the HRFs was significantly delayed in the cases of PVL as compared with that of the normal controls. Conclusion Determining the characteristics of both the BOLD response and the ER fMRI activation may play an important role in the cortical visual assessment of infants with PVL.

Leptospirosis is a common zoonosis worldwide. Leptospires are water borne spirochaetes which cause widespread immune-mediated capillary endothelial damage. A biphasic illness occurs with an acute infection followed by a secondary immune phase. We report the case of a 34 year old man who developed serologically confirmed leptospirosis during a fishing trip in France. This led to Weil9s disease with hepatorenal dysfunction. After 3 weeks of antibiotic treatment, he was making a sustained recovery when he developed a rapid onset of headache without meningism, altered mental function, bilateral cortical visual impairment and focal seizures. At the onset of his symptoms there was a small rise in blood pressure from 170/90 to 161/111 millimeters of mercury. Renal and hepatic function were improving. He had started to pass urine. The seizures resolved with phenytoin. No other treatment changes were made. MRI with diffusion weighting revealed nonhaemorrhagic subcortical white matter lesions maximal in the occipital lobes. The patient9s symptoms rapidly improved over days and this was paralleled by resolution of the white matter lesions. We postulate that secondary immune-mediated capillary endothelial damage, a common mechanism underlying PRES, may have been a factor in producing vasogenic oedema in the while matter in this patient. Metabolic dysfunction and hypertension may have contributed. Early imaging facilitated conservative management with full recovery.

A 21-year-old male presented with occipital lobes that were extensively damaged by bilateral infarcts present at birth. The absence of the striate cortex was confirmed with anatomic and functional MRI and high-resolution EEG. His cortical visual impairment was severe, but he retained a remarkable ability to see fast-moving stimuli. Horizontal optokinetic nystagmus could be elicited from either eye. Resolution acuity was close to normal providing the patient was allowed to move his head and eyes. The direction of motion in random-dot patterns could be discriminated with perfect accuracy at speeds above 2 deg/s, and the patient reported that he could 'see' the motion at fast but not at slow speeds. This conscious residual vision for motion is known as Riddoch's phenomenon, but it has never been reported in the complete absence of the striate cortex. Functional neuroimaging revealed activation that was outside the motion-responsive regions of the extrastriate cortex. This case demonstrates remarkable plasticity in the human visual system and may have implications for understanding the functional organization of the motion pathways.

We examined 30 infants in whom cortical visual impairment was diagnosed during their first year of life to ascertain prognostic factors for the development of object vision, defined as the ability to recognize faces or hand-held toys. All patients were followed up for a minimum of 12 months. The most common causes of cortical visual impairment in the 30 infants were hydrocephalus in nine infants (30.0%), birth asphyxia or neonatal hypoxia in eight infants (26.7%), intracranial hemorrhage with or without hydrocephalus in seven infants (23.3%), and meningitis in five infants (16.7%). Lack of development of object vision was associated only with hypoxia (P = .013). Findings on ophthalmic examination, an abnormality in the visual pathway on computed tomographic or magnetic resonance scan, and seizures, hydrocephalus, intracranial hemorrhage, meningitis, cerebral palsy, developmental delay, prematurity, microcephaly, and hearing deficit, did not appear to be risk factors for the lack of development of object vision.

• Three children with congenital hydrocephalus are described in whom increased intracranial pressure was associated with severe, long-lasting cortical visual impairment. Following shunt revisions or reconstructive craniotomies, visual improvement began within hours. It is speculated that increased intracranial pressure can occasionally result in chronic hypoperfusion of the parietal-occipital lobes, either due to posterior cerebral artery compromise secondary to transtentorial pressure gradient or to direct compression of cerebral tissues.

Forced-choice preferential-looking acuity estimates from cortically visually impaired (CVI) infants and children were compared with three measures of visual function. Mean acuity deficit varied with fixation, tracking and visual impairment. Acuity deficit correlated with centile score for sensorimotor skills, but not for gross motor skills. The results suggest that these estimates provide information about the CVI child's ability to use vision in everyday life. Correlations were found between initial acuity deficits and acuity deficits measured from three months to six years later. Forced-choice preferential-looking acuity estimates may be useful for evaluating treatment response and establishing guidelines for educational materials for these infants and children.

Aim: To describe the visual problems which children with brain damage may experience and to describe approaches to these, applicable to everyday life. Methods: A literature-based essay is presented using relevant articles and practical experience. Results: Damage to the brain can affect both visual input and visual processing. Degradation of visual input results in reduced visual acuity, reduced contrast sensitivity and restricted visual fields. The dorsal stream passes between the occipital cortex and the posterior parietal lobes, which serve the ability to extract visual data from a complex scene, visual attention and the visual guidance of movement. The ventral stream passes between the occipital lobes and the temporal lobes and is responsible for recognition of what is being looked at and orientation. Any of these visual functions can be impaired to any degree and in any combination. Structured history-taking and clinical examination is required to fully characterise the visual problems in each affected child in order to devise a tailored management strategy matched to the child’s needs. Conclusion: Structured history-taking and clinical examination in children with visual impairment secondary to brain damage can allow management to be customised to the individual requirements of that child.

This study assessed the prevalence and characteristics of light-gazing by all visually impaired children referred during a 2 1/2-year period. Light-gazing (compulsive staring into lights) is one of the many clinical signs of cortical visual impairment (CVI), and in the present study it occurred in 60 per cent of children with CVI. The authors believe that light-gazing by any child with ocular lesions indicates some degree of CNS involvement. Visually impaired children who flicker their fingers in front of their eyes against a light source demonstrate an extension of this compulsive behaviour. This and other studies suggest that blind mannerisms have specific neuropathological substrata and therefore are useful clinical signs.

There is a high prevalence of ocular defects in children with developmental disabilities. This study evaluated visual disability in a group of 200 cerebral palsy (CP) patients and found that 68% of the children had significant visual morbidity. These findings emphasize the need for an early ocular examination in patients with CP.

Aims. The aim of the study was to assess cortical visual function in infants with cystic periventricular leukomalacia (PVL). Methods. Patients with type 3 PVL were assessed at 12 months corrected age using a battery of tests specifically designed to assess various aspects of visual function, including ocular movements, visual acuity (Keeler cards), visual fields and fixation shift. Infants with moderate or severe retinopathy (>stage 1) were excluded. Results. Thirteen infants (5 m, 8 f) with GA 30.6 + 3.7 weeks and BW 1573 + 583 grams were included in the study. All had some abnormalities of visual function but the spectrum of severity observed was very wide, ranging from isolated abnormal ocular movements to severe abnormalities on all the aspects of visual function assessed. Ocular movements abnormalities were frequent (11/13) often associated to inability to follow an object for a complete arc. Acuity was reduced in 9/13, fixation shift was abnormal in 11/13 and visual fields were reduced in 10/13. Brain MRI was available in 12 of the 13 infants and all had abnormal optic radiations. The infants who also had obvious signs of atrophy of the thalami had a higher risk of developing more severe visual abnormalities. Conclusions. Our results suggest that visual abnormalities are frequent in infants with cystic PVL and that a detailed assessment of various aspects of visual functions should be performed in order to identify the severity of cortical visual impairment.

Cortical visual impairment (CVI) is the leading cause of bilateral visual impairment in children in Western countries. This finding reflects better methods for identifying visual impairment due to CNS injury and also advances in perinatal care, which have increased the survival rate of children with neurological morbidity. This review will describe advances in the diagnosis and management of CVI. Central to our discussion is a definition of CVI that includes a decrease in visual acuity. New treatment and rehabilitative measures are badly needed for this disorder. We hope to stimulate interest in CVI, a disease that has become a significant public health problem.

Neurological lesions that cause dyskinetic cerebral palsy (CP) commonly involve ocular movements. This report describes a group of 14 children (nine males, five females) whose CP is associated with severe dyskinetic eye movements. Ages ranged from 4 months to 13 years (mean 6.9 years). Clinical features of this eye movement disorder are discussed and defined. The visual function of these children is slow, variable, and highly inefficient. They are often misdiagnosed as blind, due to cortical visual impairment. Early recognition of dyskinetic eye moment disorder and appropriate developmental and educational management are important.

Cerebral venous thrombosis is an important cause of stroke in children. Understanding the natural history of the disease is essential for rational application of new interventions. We retrospectively identified 31 children with cerebral venous thrombosis confirmed by head computed tomography (4 patients) or by magnetic resonance imaging (27 patients). Risk factors, clinical and radiographic features, and neurologic outcomes were analyzed. There were 21 males and 10 females aged 1 day to 13 years (median 14 days). Nineteen (61%) were neonates. The most common risk factors included mastoiditis, persistent pulmonary hypertension, cardiac malformation, and dehydration. The chief clinical features were seizures, fever, respiratory distress, and lethargy. Fifteen patients had infarctions (8 hemorrhagic, 7 ischemic). Protein C and antithrombin III deficiency were the most common coagulopathies among 14 tested patients. On discharge, 11 patients were normal, 17 had residual deficits, and 2 patients died. Twenty-seven patients were followed from 1 month to 12 years (mean 22 months). At follow-up, 11 patients were normal, and 13 patients had development delay. One had residual hemiparesis and cortical visual impairment. Two had other deficits. Neonatal cerebral venous thrombosis is probably more common than previously thought, and outcomes are worse in this group. All children with cerebral venous thrombosis should be tested for coagulation disorders. (J Child Neurol 2001;16:574-580).

To the Editor. —I read with interest the article by Connolly et al, entitled "Rapid Recovery From Cortical Visual Impairment Following Correction of Prolonged Shunt Malfunction and Congenital Hydrocephalus." 1 The authors indicated that the three patients had long periods of elevated intracranial pressure secondary to shunt malfunction. They did not indicate how they knew that the pressure levels were elevated. Perhaps the patients had prolonged periods of shunt malfunction leading to an increase in intracranial pressure because of the reluctance to invasively measure intracranial pressure. The authors did mention that visual evoked potentials were used for evaluations of the patients, but they did not indicate how these were obtained. Visual evoked potentials have been found helpful in noninvasively estimating intracranial pressure levels in patients with acute hydrocephalus in shunts. 2,3

Cortical visual impairment (CVI) in children is most commonly caused by peri- or post-natal hypoxia-ischemia, but may also occur following other insults, e.g., trauma, epilepsy, infections, drugs or poisons, and certain neurologic diseases. The disorder differs considerably in etiology, physical findings, and, perhaps, prognosis, from the cortical blindness seen in adults. The same event that causes CVI by damaging the geniculate and/or extrageniculate visual pathways may also damage other areas of the brain, or the retina, optic nerves, or chiasm. Thus, children with CVI often have other neurological problems. Diagnosis may require the participation of a multidisciplinary team and the use of special visual testing techniques. Due to the uncertainty concerning the prognosis in CVI, clinicians should remain optimistic about the child's potential for some vision recovery.

Visual defects are often poorly recognized in children with multiple neurologic problems due to perinatal hypoxic-ischemic encephalopathy. We report the clinical, radiologic, and electrodiagnostic characteristics of 20 children with cortical visual impairment secondary to birth asphyxia. Clinical diagnosis often was delayed. Ten patients recovered vision during the first two years of life. Four infants had coexisting damage to the pregeniculate visual pathway. Useful investigations included cranial computed tomography and visual evoked potential mapping. Electroencephalographic abnormalities were nonspecific. The classical definition of cortical blindness must be modified for children.

The time of onset of congenital horizontal nystagmus is usually known. We present a group of infants in whom this was determined objectively. In two, vertical nystagmus in the neonatal period became horizontally directed, at 4 months in one, and between 7 and 9 months of age in the second. Two infants (one an oculocutaneous albino) had no visual response initially but subsequently developed horizontal nystagmus as the vision improved at 5 and 6 1/2 months: Type III delayed visual maturation. An infant totally blind due to Norrie's disease was examined in the first week of life but did not develop nystagmus for a further 3 months. Two children with cortical visual impairment never developed nystagmus. In early infancy, vision is thought to be predominantly subcortical. Therefore the development of nystagmus at a time when the geniculostriate system is emerging functionally (around 3 months), and its absence in cortical visual impairment, has led us to propose a hypothesis suggesting that a functioning geniculostriate system is a prerequisite for the development of horizontal nystagmus.

The electroencephalograms of 40 children with permanent cortical visual impairment (CVI) were studied. CVI was diagnosed in the presence of severe visual loss, normal or minimal ocular findings and clinical, electrodiagnostic and CT evidence of postgeniculate lesions involving the visual cortex. All patients had a multidisciplinary evaluation, including extensive neurological and ophthalmological investigations. The records did not contain any specific features which would be diagnostic of CVI. Isolated occipital spikes were rare and more commonly multifocal EEG disturbance was seen because of diffuse cerebral involvement. Photic stimulation was of little use in the diagnosis. Multihandicapped children with profound CVI tended to show multifocal abnormalities, no alpha rhythm and a suppressed posterior waking background in their EEGs, whereas those with more residual vision usually had an alpha rhythm. The presence or absence of alpha rhythm seemed to reflect the intactness of the striate cortex. However, the lack of alpha rhythm was not always associated with total blindness and not all children with useful residual vision had alpha rhythm.

Fifty patients with permanent cortical visual impairment were evaluated. They had a characteristic behaviour profile, usually with residual sight but poor visual attention. 30 of the 50 also had damage to the anterior visual pathway. Visual evoked potential mapping was shown to have a clear advantage over visual evoked responses, and using that in conjunction with CT and clinical data enabled several subgroups of cortical visual impairment to be identified. The diagnosis probably is more common than previously recognised, and should be suspected when there is greater delay in visual development in other areas and the degree of visual loss is unexplained by ocular findings. Using traditional criteria for cortical blindness may mean that many children are not diagnosed, which has serious implications for their rehabilitation.

The common behavioral features of 50 children with permanent cortical visual impairment (CVI) are described. CVI is frequently associated with specific behavioural characteristics. The majority of these children have residual vision, but they all have variable and inconsistent visual performance, including visual acuity. They see better in familiar environments and when they understand what to look for and where to look for it. They often use touch to identify objects. Their ability to identify colours is much stronger than their perception of form. Many turn their heads to the side when they are reaching. Nystagmus and visual self-stimulation are exceptionally rare. They appear to have great difficulty with the cognitive evaluation of visual perception in spatial terms. Head elevation is worst in those with least vision, and without head elevation the possibility of visual stimulation is further restricted.

The assessment of cortical visual impairment in handicapped children is often difficult and the diagnosis may be delayed for several years, particularly when the child is difficult to examine [1]. The striate cortex receives and transmits visual information to the association areas. Thus it governs the ability to resolve fine detail (visual acuity) and acts as a gateway to conscious visual analysis. More complex visual interpretation occurs in the association areas. Total destruction of the striate cortex results in loss of vision for conscious visual analysis. Destruction of the association areas results in visual agnosia and such individuals see without being able to recognise. Because of the similarities in their visual behaviour, it is difficult clinically to distinguish between profound visual agnosia and severe loss of visual acuity in multihandicapped children.

Damage to the cerebral cortex was responsible for impairment in vision in 90 of 130 consecutive children referred to the Vision Assessment Clinic in Glasgow. Cortical blindness was seen in 16 children. Only 2 were mobile, but both showed evidence of navigational blind-sight. Cortical visual impairment, in which it was possible to estimate visual acuity but generalised severe brain damage precluded estimation of cognitive visual function, was observed in 9 children. Complex disorders of cognitive vision were seen in 20 children. These could be divided into five categories and involved impairment of: (1) recognition, (2) orientation, (3) depth perception, (4) perception of movement and (5) simultaneous perception. These disorders were observed in a variety of combinations. The remaining children showed evidence of reduced visual acuity and/ or visual field loss, but without detectable disorders of congnitive visual function. Early recognition of disorders of cognitive vision is required if active training and remediation are to be implemented.