The diagnostic value of MRI findings in pediatric idiopathic intracranial hypertension: a case-control study.

BACKGROUND: Idiopathic intracranial hypertension (IIH) is a rare medical condition in children. Based on the different radiological findings reported in various studies in pediatric IIH, this study was conducted to determine the diagnostic value of MRI findings in diagnosing IIH in children. METHODS: In this retrospective study, the medical records of all children aged 1 to 18 years who visited Ghaem Hospital in Mashhad, Iran, between 2012 and 2022 and were diagnosed with IIH were gathered. Forty-nine cases of children with IIH and 48 control cases of children with the first unprovoked seizure with no indications of increased intracranial pressure for comparison were selected. Patient demographic information and MRI findings were extracted. The comparison between different MRI findings in the case and control groups was conducted using statistical tests. RESULTS: In the case group, the mean diameter of the subarachnoid space expansion around the optic nerve was 5.96 ± 1.21, compared to 4.79 ± 0.33 in the control group, with statistically significant difference (P < 0.001). All the patients with flattening of the posterior globe or transverse sinus stenosis were in the case group, and the frequency of these findings in the case group was significantly higher than in the control group (P < 0.001). The majority of patients (95.5%) classified under category 3 and 4 of empty sella were part of the case group, and the statistical test results indicated a significant difference between the two groups (P < 0.001). The optic nerve sheath diameter cut-off of 5.35 mm, when used for expansion of the subarachnoid space around the optic nerve, with a sensitivity of 82% and a specificity of 100% in diagnosing IIH. CONCLUSION: The most reliable diagnostic indicators for diagnosing IIH in children are perioptic subarachnoid space expansion with high sensitivity, and posterior globe flattening and transverse sinus stenosis with high specificity.

The Gross, Fine, and Oral Motor Functions in a Patient with Megalencephalic Leukoencephalopathy with Subcortical Cyst: A Case Report.

Megalencephalic Leukoencephalopathy with Subcortical Cysts (MLC) is a rare autosomal recessive neurodegenerative disorder. As motor deficits are a core feature of MLC, the present study reported on an MLC1 patient's gross, fine, and oral motor functions. Our patient demonstrated macrocephaly, deterioration of motor functions with ataxia, spasticity, and intellectual disability. In addition to medical interventions, the patient received rehabilitation interventions of occupational therapy and speech therapy. Brain structures were analyzed with magnetic resonance imaging (MRI), and gross, fine, and oral motor functions were analyzed with Gross Motor Function Measurement (GMFM), Purdue Pegboard Test (PPT), and Oral Motor Assessment Scale (OMAS) at age two and after interventions at age five. The results showed that although the motor functions did improve due to the interventions, the patient still had weaknesses in gross, fine, and oral motor functions when compared to his peers. These findings emphasized the importance of early referral for rehabilitation of motor function in order to increase their independence, participation in daily tasks, and quality of life.

Bi-allelic Loss of Human APC2, Encoding Adenomatous Polyposis Coli Protein 2, Leads to Lissencephaly, Subcortical Heterotopia, and Global Developmental Delay.

Lissencephaly is a severe brain malformation in which failure of neuronal migration results in agyria or pachygyria and in which the brain surface appears unusually smooth. It is often associated with microcephaly, profound intellectual disability, epilepsy, and impaired motor abilities. Twenty-two genes are associated with lissencephaly, accounting for approximately 80% of disease. Here we report on 12 individuals with a unique form of lissencephaly; these individuals come from eight unrelated families and have bi-allelic mutations in APC2, encoding adenomatous polyposis coli protein 2. Brain imaging studies demonstrate extensive posterior predominant lissencephaly, similar to PAFAH1B1-associated lissencephaly, as well as co-occurrence of subcortical heterotopia posterior to the caudate nuclei, "ribbon-like" heterotopia in the posterior frontal region, and dysplastic in-folding of the mesial occipital cortex. The established role of APC2 in integrating the actin and microtubule cytoskeletons to mediate cellular morphological changes suggests shared function with other lissencephaly-encoded cytoskeletal proteins such as α-N-catenin (CTNNA2) and platelet-activating factor acetylhydrolase 1b regulatory subunit 1 (PAFAH1B1, also known as LIS1). Our findings identify APC2 as a radiographically distinguishable recessive form of lissencephaly.

A Common Ancestral Asn242Ser Mutation in TMEM67 Identified in Multiple Iranian Families with Joubert Syndrome.

BACKGROUND: Joubert syndrome (JS) is a clinically and genetically heterogeneous group of rare neurodevelopmental disorder characterised by peculiar midbrain-hindbrain malformation, known as the "molar tooth" sign. JS can manifest a broad range of signs and symptoms. The most common features of JS are hypotonia, ataxia, developmental delay/intellectual disability, abnormal eye movements, and neonatal breathing abnormalities. To date, 29 genes have been shown to cause JS. METHODS: We employed whole-genome single nucleotide polymorphism genotyping in a group of Iranian families with JS and Sanger sequencing of a known mutation associated with JS located in a single homozygous regions shared by affected members of the families. RESULTS: Homozygosity mapping uncovered a shared ∼2.2-Mb run of homozygosity on chromosome 8q21.3-q22.1 encompassing the known JS-causing TMEM67 gene. Sanger sequencing of a known mutation (NM_153704.5: c.725A>G; p.Asn242Ser) in TMEM67 identified from studying another Iranian family using whole-exome sequencing confirmed the presence of the homozygous mutation in 22 affected members of 12 nuclear families. "Molar tooth" sign of brain magnetic resonance imaging, moderate-to-severe neurodevelopmental delay, and abnormal eye movements were the most common features of affected individuals. In addition, liver disease, seizure, behavioural abnormalities, failure to thrive, and kidney disease were observed variably in some of the patients. CONCLUSION: We propose that Asn242Ser is a founder mutation in the Iranian population, which might explain a significant proportion of JS cases from eastern Iran. Therefore, screening for this variant should be considered for genetic testing in Iranian patients with JS. In addition, this finding is important for developing population-specific genetic testing in Iran.

Homocystinuria: A Rare Disorder Presenting as Cerebral Sinovenous Thrombosis.

Objective Homocystinuria is an inborn error of amino acid metabolism caused by cystathionine beta-synthase deficiency that affects methionine metabolism. The clinical features are heterogeneous ranging from mental retardation, ectopia lentis, and osteoporosis to vascular events such as deep vein thrombosis, sagital sinus thrombosis, and myocardial infarction. Cerebral sinovenous thrombosis (CVST) is an unusual disorder in children and requires prompt and accurate management. Some causal factors for the development of CVST differ between children and adults. The majority of cases with CSVT are found to have an underlying cause for thrombosis like dehydration, infections, prothrombotic and hematologic disorders, malignancy and trauma. Although homocystinuria is usually associated with ischemic strokes, CVST as initial clinical presentation of homocystinuria is rare in children. In this article, we presented a 10-year old boy with seizure, hemiparesis, and ataxia due to CSVT caused by homocystinuria.