Meral Özmen

Whole-exome sequencing identifies recessive WDR62 mutations in severe brain malformations

The development of the human cerebral cortex is an orchestrated process involving the generation of neural progenitors in the periventricular germinal zones, cell proliferation characterized by symmetric and asymmetric mitoses, followed by migration of post-mitotic neurons to their final destinations in six highly ordered, functionally specialized layers. An understanding of the molecular mechanisms guiding these intricate processes is in its infancy, substantially driven by the discovery of rare mutations that cause malformations of cortical development. Mapping of disease loci in putative Mendelian forms of malformations of cortical development has been hindered by marked locus heterogeneity, small kindred sizes and diagnostic classifications that may not reflect molecular pathogenesis. Here we demonstrate the use of whole-exome sequencing to overcome these obstacles by identifying recessive mutations in WD repeat domain 62 (WDR62) as the cause of a wide spectrum of severe cerebral cortical malformations including microcephaly, pachygyria with cortical thickening as well as hypoplasia of the corpus callosum. Some patients with mutations in WDR62 had evidence of additional abnormalities including lissencephaly, schizencephaly, polymicrogyria and, in one instance, cerebellar hypoplasia, all traits traditionally regarded as distinct entities. In mice and humans, WDR62 transcripts and protein are enriched in neural progenitors within the ventricular and subventricular zones. Expression of WDR62 in the neocortex is transient, spanning the period of embryonic neurogenesis. Unlike other known microcephaly genes, WDR62 does not apparently associate with centrosomes and is predominantly nuclear in localization. These findings unify previously disparate aspects of cerebral cortical development and highlight the use of whole-exome sequencing to identify disease loci in settings in which traditional methods have proved challenging.

Bone mineral density in children with neurofibromatosis 1

Aim: Our aim was to detect the status of bone mineral density (BMD) in children with NF1, and thus to help the management of the skeletal complications of NF1.

Vitamin K deficiency--late onset intracranial haemorrhage.

A retrospective study is presented of the clinical features and outcome of late onset haemorrhagic disease due to vitamin K deficiency in 11 babies who were admitted to the emergency or child neurology unit during a 4-year period (January 1994-December 1997). The disease occurred in infants between 30 and 119 days of age (mean: 56+/-24 days). None of them received vitamin K after birth and all were breastfed. The presenting complaints were seizures (91%), drowsiness (82%), poor sucking (64%), vomiting (46%), fever (46%), pallor (46%), acute diarrhoea (27%), irritability and high-pitched cry (18%). On examination, tense or bulging fontanelle (73%), anisocoria (36%), weak neonatal reflexes (18%), cyanoses (18%) were the most frequent findings. The localizations of the intracranial haemorrhage were as follows: intracerebral (91%), subarachnoid (46%), subdural (27%), and intraventricular (27%). No fatality was observed. However, after a follow-up period ranging from 6 to 48 months (mean: 21+/-13 months), only three (27%) infants remained neurologically normal. Seizure disorders (73%), severe psychomotor retardation (46%), cerebral palsy (46%) and microcephaly (46%) were observed in the remainder. Hydrocephalus developed in three (27%) babies but none of them required shunt replacement. The value is emphasized of vitamin K prophylaxis in the newborn to reduce the incidence of late onset intracranial haemorrhage and handicap in children.

Wii-based Balance Therapy to Improve Balance Function of Children with Cerebral Palsy: A Pilot Study.

[Purpose] Cerebral palsy is a sensorimotor disorder that affects the control of posture and movement. The Nintendo® Wii Fit offers an inexpensive, enjoyable, suitable alternative to more complex systems for children with cerebral palsy. The aim of this study was to investigate the efficacacy of Wii-based balance therapy for children with ambulatory cerebral palsy. [Subjects] This pilot study design included fourteen ambulatory patients with cerebral palsy (11 males, 3 females; mean age 12.07 ± 3.36 years). [Methods] Balance functions before and after treatment were evaluated using one leg standing, the functional reach test, the timed up and go test, and the 6-minute walking test. The physiotherapist prescribed the Wii Fit activities,and supervised and supported the patients during the therapy sessions. Exercises were performed in a standardized program 2 times a week for 12 weeks. [Results] Balance ability of every patient improved. Statistically significant improvements were found in all outcome measures after 12 weeks. [Conclusion] The results suggest that the Nintendo® Wii Fit provides a safe, enjoyable, suitable and effective method that can be added to conventional treatments to improve the static balance of patients with cerebral palsy; however, further work is required.

Clinical assessment, MRI, and EMG in congenital brachial plexus palsy.

Thirteen infants with congenital brachial plexus palsy (eight with upper, five with upper and lower) were monitored by magnetic resonance imaging (the first performed between 7 and 41 days of age and the second at 3 months of age), electromyography (the first performed between 27 and 50 days and the second at 3 months), and the muscle scoring system of the Hospital for Sick Children (at 3, 6, and 9 months of age). The findings were evaluated with respect to the clinical status of the patients at 12 months of age. Magnetic resonance imaging, which could be performed readily even in the neonatal period, revealed pseudomeningoceles in two of the five patients with a poor prognosis (in all planes even in the early days after birth) and in two of the eight patients with a good prognosis (more easily visible at 3 months of age). Electromyography implied root avulsion in three of five patients with a poor prognosis. Electromyography can be of great value for patients with a poor prognosis and root avulsion but may underestimate the severity. The muscle scoring system (Hospital for Sick Children) was determined to be the most predictive method for prognosis.

Muscle ultrasonography and electromyography correlation for evaluation of floppy infants

Floppiness in an infant may have a number of different etiologies from disorders of the brain to spinal cord lesions, neuropathies, neuromuscular junction disorders and myopathies. In this study we aimed to investigate the correlation of muscle ultrasonography (US) and electromyography (EMG) in the diagnosis of floppy infants. The study encompassed 41 floppy infants aged 2-24 months. The muscle US and EMG examinations were performed without awareness of the clinical diagnosis. The final diagnosis was established by molecular genetic tests or muscle/nerve biopsy. The neurogenic group consisted of 16 infants according to their US and EMG findings. Fifteen of them had spinal muscular atrophy proven by genetic analysis and one had polyneuropathy diagnosed by nerve biopsy. Six infants were in the myopathic group according to their muscle US and EMG results. All of them underwent muscle biopsy and microscopic examination revealed five congenital muscular dystrophy and one glycogen storage disease. In two infants the US and EMG data conflicted. Their biopsies were also insufficient for the diagnosis. Seventeen infants had normal US and EMG findings but pathologic cranial magnetic resonance imaging or metabolic/genetic tests. They were considered in the group of central hypotonia. Our results suggest a high concordance of US and EMG findings in the diagnostic work-up of neurogenic and myopathic disorders.

Quantification of neurometabolites in subacute sclerosing panencephalitis by 1H-MRS

The authors studied 20 patients with subacute sclerosing panencephalitis (SSPE) to investigate the correlations between MRI, magnetic resonance spectroscopy (MRS), and clinical status. MRI findings did not correlate with clinical status. By contrast, all patients had reductions in N-acetyl aspartate (NAA) and increase in myoinositol (mI) (p < 0.01), and NAA and mI concentrations correlated with clinical severity (p < 0.05). During follow-up, NAA continued to decline. 1H-MRS may be a useful measure of disease severity and progression in SSPE.

Preliminary Anatomical and Neurodevelopmental Outcomes of Intravitreal Bevacizumab As Adjunctive Treatment for Retinopathy of Prematurity

Abstract Purpose: To evaluate the two-year follow-up of patients with type 1 retinopathy of prematurity (ROP) who received intravitreal bevacizumab (IVB) as adjunctive treatment. Materials and methods: We conducted a longitudinal follow-up study of premature infants who received 0.625 mg IVB therapy in addition to standard laser photocoagulation therapy. For comparison of the ophthalmological and neurological assessment outcomes of these infants, a control group was formed with 13 birth weight- and gestational age-matched infants who were treated with laser therapy alone for type 1 ROP. The neurological status of the study group and the control group was examined systematically, and neurodevelopmental evaluation was assessed by the Bayley Scales of Infant Development (BSID-III). Results: A total of 18 eyes of 13 infants were included in the study. Anatomical success was obtained in 14 eyes (78%) and retinal detachment was observed in 4 eyes (22%). At two years of age, no significant difference was found in terms of spherical or cylindrical refractive errors compared to the control group. In control group, 2/13 patients’ and in study group, 3/13 patients’ neurological examinations were abnormal. No significant difference was found in the mean cognitive, language or motor BSID-III test scores of the groups. Conclusions: IVB appears to be useful for advanced ROP when laser treatment is precluded or not sufficient for preventing the progression of ROP. This pilot study indicates that IVB seems to contribute no further complications to the complications already present due to prematurity.

Evaluation of etiologic and prognostic factors in neonatal convulsions.

This study evaluated etiologic and risk factors affecting long-term prognoses of neurologic outcomes in newborns with neonatal seizures. We enrolled patients at chronologic ages of 23-44 months, referred to the Department of Pediatric Neurology, Istanbul Medical Faculty, from January 1, 2007-December 31, 2009, after manifesting seizures in their first postnatal 28 days. Of 112 newborns, 41 were female, 71 were male, 33 were preterm, and 79 were full-term. Perinatal asphyxia (28.6%) and intracranial hemorrhage (17%) were the most common causes of neonatal seizures. Cerebral palsy developed in 27.6% of patients during follow-up. The incidence of epilepsy was 35.7%. Almost 50% of patients manifested developmental delay in one or more areas. Global developmental delay was the most common (50.8%) neurologic disorder. The correlation between gestational age or birth weight and adverse outcomes was nonsignificant. Etiology, Apgar score, need for resuscitation at birth, background electroencephalogram, neonatal status epilepticus, cranial imaging findings, type/duration of antiepileptic treatment, and response to acute treatment were all strong prognostic factors in neurologic outcomes. Neonatal seizures pose a threat of neurologic sequelae for preterm and full-term infants. Although the number of recognized etiologic factors in neonatal seizures has increased because of improvements in neonatology and diagnostic methods, perinatal asphyxia remains the most common factor.

Using the Modified Checklist for Autism in Toddlers in a well-child clinic in Turkey: Adapting the screening method based on culture and setting:

We aimed to adapt the Modified Checklist for Autism in Toddlers to Turkish culture. The Modified Checklist for Autism in Toddlers was filled out independently by 191 parents while they were waiting for the well-child examination of their child. A high screen-positive rate was found. Because of this high false-positive rate, a second study was done in which the Modified Checklist for Autism in Toddlers was administered by health-care staff in a short interview with two groups of parents. The first group (the high-risk group) comprised 80 children aged 18–36 months, who were initially diagnosed with pervasive developmental disorders. The second group (the low-risk group) comprised 538 children of the same age, who were followed regularly by the well-child clinic. Two screen positives were found in the low-risk group. These two children, a random sample of 120 children from the low-risk group, and all the high-risk group were invited to a clinical evaluation. The diagnostic power of the Modified Checklist for Autism in Toddlers was assessed against clinical diagnosis and the Childhood Autism Rating Scale. The positive predictive value of the Modified Checklist for Autism in Toddlers was found to be 75%. Our findings led us to conclude that the Modified Checklist for Autism in Toddlers is a useful tool in Turkey for screening of pervasive developmental disorders in primary care, but in our culture, it is completed more accurately when health-care personnel ask the parents the questions. This study shows that Modified Checklist for Autism in Toddlers screening should be adapted based on culture and setting.