Lena Jacobson

Periventricular Leukomalacia ☆: An Important Cause of Visual and Ocular Motility Dysfunction in Children

The immature visual system in infants born preterm is vulnerable to adverse events during the perinatal period. Periventricular leukomalacia affecting the optic radiation has now become the principal cause of visual impairment and dysfunction in children born prematurely. Visual dysfunction is characterized by delayed visual maturation, subnormal visual acuity, crowding, visual field defects, and visual perceptual-cognitive problems. Magnetic resonance imaging is the method of choice for diagnosing this brain lesion, which is associated with optic disk abnormalities, strabismus, nystagmus, and deficient visually guided eye movements. Children with periventricular leukomalacia may present to the ophthalmologist within a clinical spectrum from severe cerebral visual impairment in combination with cerebral palsy and mental retardation to only early-onset esotropia, normal intellectual level, and no cerebral palsy. Optimal educational and habilitational strategies need to be developed to meet the needs of this group of visually impaired children.

Visual impairment in preterm children with periventricular leukomalacia--visual, cognitive and neuropaediatric characteristics related to cerebral imaging.

Thirteen preterm children, aged 4 to 14 years, with visual impairment due to periventricular leukomalacia (PVL) were evaluated for visual function, intellectual level, cognitive profile and motor function. Their visual impairment was characterized by low acuity, crowding, visual field defects and ocular motility disturbances. Their cognitive profile was uneven, often with considerably higher scores on verbal than on visual‐spatial tasks. Nine children had normal intelligence, three had mild mental retardation and one had severe mental retardation. In all the children, visual impairment was complicated by visual perceptual difficulties, accounting for their greater visual handicap than would be expected from their visual acuities and strabismus alone. Though CT or MRI revealed bilateral PVL in all the children, six had no motor impairment consistent with cerebral palsy, which is an unexpected finding.

Low Gestational Age Associated with Abnormal Retinal Vascularization and Increased Blood Pressure in Adult Women

The objective was to investigate any possible relationship between functional and structural vascular changes in women with low gestational age and/or low birth weight by analyzing the retinal vascular pattern in women with thoroughly documented blood pressure. Retinal vessel morphology was evaluated by digital image analysis of ocular fundus photographs in 47 subjects, aged 23–30 y. The women were allocated into three groups: 1) those born preterm and appropriate for gestational age (AGA), with a median gestational age at birth of 30 wk and a median birth weight of 1250 g (n = 14); 2) those born small for gestational age (SGA) but full term (median 40 wk), with a median birth weight of 2130 g (n = 17), and 3) those born full term, AGA, and with a median birth weight of 3640 g (n = 16). Women born preterm had significantly higher length index for arterioles compared with the other two groups (median 1.11 and 1.08, respectively, p = 0.005). In addition, the preterm-born women had significantly fewer number of vascular branching points compared with the controls (median 27 and 30, respectively, p = 0.03). The abnormal retinal vascularization observed in ex-preterm women together with an increased casual blood pressure observed in these subjects suggests that being born preterm does have effects on the vascular system that persist into adult life. In addition, it demonstrates that preterm birth seems to affect the vascular system both functionally and structurally, which, in adulthood, could result in a lower threshold for the development of vascular disease.

Nystagmus in periventricular leucomalacia

BACKGROUND/AIMS Periventricular leucomalacia (PVL) is a lesion in the immature brain involving the optic radiation. Children with PVL have visual problems including crowding, visual field defects, strabismus, and visual perceptual/cognitive deficits, together with nystagmus. They often have optic nerve hypoplasia seen either as small discs or as large cupping of normal sized optic discs. This study aimed to perform eye movement recordings in a group of children with PVL in order to characterise and classify the nystagmus. METHODS 19 children with PVL on cerebral imaging underwent eye movement recordings with the Ober-2 infrared reflection technique. RESULTS 16 of the 19 subjects had horizontal nystagmus. CONCLUSION The present study shows that nystagmus is commonly seen in children with PVL.

Optic disc morphology may reveal timing of insult in children with periventricular leucomalacia and/or periventricular haemorrhage

Aims: To evaluate the relation between optic disc morphology and timing of periventricular white matter damage, defined as either periventricular leucomalacia (PVL) or periventricular haemorrhage (PVH), as estimated by neuroradiology. Methods: 35 children with periventricular white matter damage who had had neuroradiology performed and ocular fundus photographs taken had their photographs analysed by digital image analysis and compared with a control group of 100 healthy full term children. Timing of brain lesion was estimated by analysis of the brain lesion pattern on neuroradiological examinations (magnetic resonance imaging or computed tomography). Results: Four of 35 children had a small optic disc area; these four children had a brain lesion estimated to have occurred before 28 weeks of gestation. Nine of 11 children with a large cup area had a PVL/PVH estimated to have occurred after 28 weeks of gestation. The children with PVL/PVH had a significantly larger cup area (median 0.75 mm2) than the control group (median 0.33 mm2) (p = 0.001) and a significantly smaller neuroretinal rim area (median 1.58 mm2) than the controls (median 2.07 mm2) (p = 0.001). Conclusion: In a child with PVL/PVH and abnormal optic disc morphology, the possibilities of timing of the lesion should be considered.

Relation between blindness due to retinopathy of prematurity and autistic spectrum disorders: a population-based study.

Children with blindness due to retinopathy of prematurity (ROP) ‐ who are at greatly increased risk of cerebral damage ‐ have been noted to have a high rate of autistic symptoms, but systematic controlled studies have been lacking. A controlled population‐based study was performed; one group was blind due to ROP (N=27) and the other was congenitally blind due to hereditary retinal disease (N=14). Fifteen of the 27 children with ROP had autistic disorder. All these children were mentally retarded and about one‐third of them had cerebral palsy. In the comparison group, two of the 14 children had autistic disorder. It is concluded that there is a strong association between ROP and autistic disorder. The association is most probably mediated by brain damage and is largely independent of the blindness per se.

PERINATAL FACTORS ASSOCIATED WITH RETINOPATHY OF PREMATURITY

The etiology of retinopathy of prematurity appears to be multifactorial. Introduction of new treatments in neonatal care may add new risk factors. We have analyzed thc relationship between 42 perinatal factors and the development of retinopathy of prematurity in 78 infants with a birth weight < 1501 g and/or gestational age < 33 weeks. We have also applied a chronological analysis of the maximum and minimum pO2 and pCO2 values. Retinopathy of prematurity was seen in 37 of 78 infants (47.4%). Nineteen factors were found to be related to the development of retinopathy of prematurity. However, when step‐wise logistic regression analysis was used, only birth weight, number of days of oxygen therapy and use of beta‐blocking agents by the mother before birth were found to be associated with the development of retinopathy or prematurity. The results suggest that medication with beta blockers immediately before birth should be used cautiously.

Visual and cerebral sequelae of very low birth weight in adolescents

Objective: To describe the visual functions and relate them to MRI findings and the intellectual level in adolescents born with very low birth weight (VLBW). Design: Population-based case–control study. Patients: 59 15-year-old VLBW adolescents and 55 sex and age-matched controls with normal birth weight. Main outcome measures: Objective clinical findings (visual acuity, stereo acuity and cycloplegic refraction) were recorded. Structured history taking was used to identify visual difficulties. The intellectual level was assessed with the Wechsler Intelligence Scale for Children (WISC). All VLBW adolescents underwent MRI of the brain. Results: Significant differences were found between the VLBW adolescents and controls regarding visual acuity (median −0.11 and −0.2, respectively; p = 0.004), stereo acuity (median 60″ and 30″, respectively; p<0.001), prevalence of astigmatism (11/58 and 0/55, respectively; p<0.001) and in full-scale IQ (mean IQ 85 and 97, respectively; p<0.001) and performance IQ (mean 87 and 99, respectively; p = 0.002). The structured history also revealed a borderline significant difference between the groups (mean problems 0.46 and 0.15 respectively; p = 0.051). 30% (17/57) of the VLBW adolescents had abnormal MRI findings and performed worse in all tests, compared with both the VLBW adolescents without MRI pathology and the normal controls. Conclusion: This study confirms previous observations that VLBW adolescents are at a disadvantage regarding visual outcome compared with those with normal birth weight. In 47%, visual dysfunction was associated with abnormal MRI findings and in 33% with learning disabilities. The adolescents with abnormal MRI findings had more pronounced visual and cognitive dysfunction. The findings indicate a cerebral causative component for the visual dysfunction seen in the present study.

Visual and perceptual characteristics, ocular motility and strabismus in children with periventricular leukomalacia

The immature visual system is vulnerable to adverse events. Periventricular leukomalacia (PVL), an end-stage lesion after hypoxia-ischemia at gestational age 24–34 weeks affecting the visual radiation, has become a principal cause of visual impairment in children. Cerebral visual dysfunction caused by PVL is characterized by delayed visual maturation, subnormal visual acuity, crowding, visual field defects, and visual perceptual-cognitive problems. Magnetic resonance imaging is the method of choice for diagnosing this brain lesion, which is associated with optic disk abnormalities, strabismus, nystagmus, and deficient visually guided eye movements. Children with PVL may present to the ophthalmologist within a clinical spectrum from severe visual impairment in combination with cerebral palsy to only early-onset esotropia, normal intellectual level and no cerebral palsy. Optimal educational and habilitational strategies need to be developed to meet the needs for this group of children.

Cognitive and behavioural characteristics in blind children with bilateral optic nerve hypoplasia.

AIM To describe cognitive and behavioural characteristics in a group of blind children with bilateral optic nerve hypoplasia (ONH). METHODS Data from records, parents, teachers, and repeated developmental assessments of 13 blind children with ONH born in 1988-1998 were analysed. All children had neuroimaging and/or hormonal evidence of midline malformations. They were all blind and able to communicate with speech. RESULTS Severe mood swings and temper tantrums were common, especially during the first years of life. Later in life, sluggish tempo, low frustration tolerance and a narrow range of interests were common. Autism had been diagnosed in 6/13 children, autistic-like condition (ALC) was found in another three. The behaviour of the remaining four children was not within the autism spectrum. Eight children had cognitive capacities within the normal or near-normal range; five had mental retardation. Autism/ALC was found in all cognitive subgroups. All children exhibited fluent speech and, of these, 12 had started to talk at the expected age, but had clear deficiencies in communicative ability. CONCLUSION These children had a common pattern of behavioural characteristics including autism spectrum disorders independent of intellectual capacities.