Synthetic MRI in Neurofibromatosis Type 1 Coban, G.; Parlak, S.; Gumeler, E. ...
American journal of neuroradiology : AJNR,
09/2021, Volume:
42, Issue:
9
Journal Article
Peer reviewed
Open access
BACKGROUND AND PURPOSESynthetic MRI enables the generation of various contrast-weighted images and quantitative data in a reasonable scanning time. We aimed to use synthetic MRI to assess the ...detection and underlying tissue characteristics of focal areas of signal intensity and normal-appearing brain parenchyma and morphometric alterations in the brains of patients with neurofibromatosis type 1. MATERIALS AND METHODSConventional MR imaging and synthetic MRI were prospectively obtained from 19 patients with neurofibromatosis type 1 and 18 healthy controls. Two neuroradiologists independently evaluated focal areas of signal intensity on both conventional MR imaging and synthetic MRI. Additionally, automatically segmented volume calculations of the brain in both groups and quantitative analysis of myelin, including the focal areas of signal intensity and normal-appearing brain parenchyma, of patients with neurofibromatosis type 1 were performed using synthetic MRI. RESULTSThe comparison of conventional MR imaging and synthetic MRI showed good correlation in the supratentorial region of the brain (κ = 0.82-1). Automatically segmented brain parenchymal volume, intracranial volume, and GM volumes were significantly increased in the patients with neurofibromatosis type 1 (P < .05). The myelin-correlated compound, myelin fraction volume, WM fraction volume, transverse relaxation rate, and longitudinal relaxation rate values were significantly decreased in focal areas of signal intensity on myelin and WM maps (P < .001); however, GM, GM fraction volume, and proton density values were significantly increased on the GM map (P < .001). CONCLUSIONSSynthetic MRI is a potential tool for the assessment of morphometric and tissue alterations as well as the detection of focal areas of signal intensity in patients with neurofibromatosis type 1 in a reasonable scan time.
Congenital myasthenic syndromes (CMSs) are heterogeneous genetic disorders that result from impaired signal transmission at the neuromuscular junction (NMJ). Congenital disorders of glycosylation ...(CDG) are a challenging group of diseases affecting different organs in particular the central nervous system and the skeletal muscle. Only recently CDG have been implicated in some forms of post-synaptic autosomal recessive CMS. The protein encoded by the DPAGT1 gene is an enzyme that catalyzes the first step in the dolichol-linked oligosaccharide pathway for glycoprotein biosynthesis. Mutations in DPAGT1 were described in patients with CMS and tubular aggregates on muscle biopsy. We report a 16 year old young man, first child of a consanguineous family, who presented with walking difficultywith onset by the age of 3 year. The motor milestones were slightly delayed. There was speech difficulty which fluctuated during the day. On examination, he had generalized muscle weakness with proximal groups being more affected, excessive lordosis, waddling gait, and contractures of the Achilles tendons. There was no bulbar or extra-ocular muscle involvement. He had a mild intellectual disability with an IQ score of 50–55. Tensilon test was positive. Electromyography revealed decrementing response to repetitive nerve stimulation. He responded well to pyridostigmine, 3,4-diaminopyridine and salbutamol treatment. We carried out whole exome sequencing and identified a novel homozygous DPAGT1 mutation (c.509A>T). The non-synonymous change (p.Tyr170Phe) is predicted to be deleterious by in silico analysis and affects an aminoacid residue that is highly conserved across species. In conclusion we report a novel mutation on the DPAGT1 gene responsible for a form of “limb-girdle CMS”. Comparing with the previously reported cases this family has mental retardation as an unusual feature and a good response to a combined treatment with pyridostigmine and 3,4-diaminopyridine.
Introduction
Headache is a frequent complaint in children and adolescents. Decision-making for neuroimaging should take into account the cost and the need for sedation in young children.
Aim
To ...evaluate the yield of MRI in pediatric headache patients seen in two large tertiary hospitals.
Methods
Data were retrospectively collected from patient records (
n
= 613) and neuroimaging reports. Headache was classified according to International Headache Society guidelines.
Results
There were 346 children with imaging studies (MRI
n
= 281, CT
n
= 65)
.
Of patients who had at least one MRI study, 29% demonstrated an abnormal finding. Findings altering the management were obtained in 21 (7%) patients: the majority (
n
= 17, 80%) had headache for less than 3 months. On the other hand, four patients with headache longer than 3 months (19%) and 12 patients with normal neurological examination (57%) had significant MRI results affecting management. None of the children in whom the diagnosis of migraine could be made on clinical grounds (
n
= 40) had a significant MRI finding.
Conclusion
Neuroimaging should be performed selectively in children with headache seen in pediatric neurology clinics, especially in headache of short duration (< 3 months) and features atypical for migraine. A normal neurological examination should not reassure the clinician.
Language delays are common in childhood, may be associated with delays in other areas of development, and can affect school performance. Various tests designed for general developmental screening or ...specifically for language are used to assess developmental status in preschool children. Knowledge of the probabilities of normal developmental milestones may simplify detection of problems and delays. The aim of this study was to determine the milestones of language development in Turkish children.
We assessed data from application of the Denver II Developmental Screening Test's Turkish standardization to 1,993 children, 976 (49.0%) boys and 1,017 (51.0%) girls aged 0.6-82.0 months. We used binary logistic regression to analyze the predicted probability of accomplishing the language items on the Denver II Developmental Screening Test.
We determined the sequence of assessed language items and the ages associated with accomplishing those items, as well as the ages at which 25, 50, 75, and 100% of children passed the items. Language items followed a sequential route. Graphs had polynomial slopes.
Curves for normal development allow detection of aberrations in the predicted course of language development, and may facilitate earlier diagnosis of delays in language.
Congenital myasthenic syndromes (CMSs) are heterogeneous genetic disorders that result from impaired signal transmission at the neuromuscular junction (NMJ). Congenital disorders of glycosylation ...(CDG) are a challenging group of diseases affecting different organs in particular the central nervous system and the skeletal muscle. Only recently CDG have been implicated in some forms of post-synaptic autosomal recessive CMS. The protein encoded by the DPAGT1 gene is an enzyme that catalyzes the first step in the dolichol-linked oligosaccharide pathway for glycoprotein biosynthesis. Mutations in DPAGT1 were described in patients with CMS and tubular aggregates on muscle biopsy. We report a 16 year old young man, first child of a consanguineous family, who presented with walking difficultywith onset by the age of 3 year. The motor milestones were slightly delayed. There was speech difficulty which fluctuated during the day. On examination, he had generalized muscle weakness with proximal groups being more affected, excessive lordosis, waddling gait, and contractures of the Achilles tendons. There was no bulbar or extra-ocular muscle involvement. He had a mild intellectual disability with an IQ score of 50–55. Tensilon test was positive. Electromyography revealed decrementing response to repetitive nerve stimulation. He responded well to pyridostigmine, 3,4-diaminopyridine and salbutamol treatment. We carried out whole exome sequencing and identified a novel homozygous DPAGT1 mutation (c.509A>T). The non-synonymous change (p.Tyr170Phe) is predicted to be deleterious by in silico analysis and affects an aminoacid residue that is highly conserved across species. In conclusion we report a novel mutation on the DPAGT1 gene responsible for a form of “limb-girdle CMS”. Comparing with the previously reported cases this family has mental retardation as an unusual feature and a good response to a combined treatment with pyridostigmine and 3,4-diaminopyridine.
Objectives To assess magnetic resonance imaging (MRI) findings in a group of 20 children below the age of 18 years diagnosed with tuberous sclerosis (TS). Methods The age of imaging and period of ...follow up, MRI characteristics of cortical tubers, subependymal nodules and other findings were recorded. Results Male/Female ratio was 6/14. Age at first imaging was 5 months to 18 years. Nine patients had follow-up imaging after 5 months–8 years. Seven of them were stable. One patient underwent tuber resection and temporal lobectomy. One patient had a partially calcified 2×1.5 cm subependymal giant cell astrocytoma which showed cystic degeneration and growed into 3×5.5 cm size on follow up. Six of all had cranial tomography. None had spinal imaging. Cortical tubers were mostly seen in frontal and parietal lobes. 2 patients had cerebellar tubers which were calcified. Ten patients had cortical cystic degeneration, 12 had calcification and 2 had Gadolinium enhancement in cortical tubers. Radial band was present in all but one. Subependymal nodules were mostly located around corpus of lateral ventricles and adjacent to foramen Monro (13/19). Amount of subependymal nodules ranged between 3–15 with a size of 2–9 mm. Seven patients had Gadolinium enhancement and 15 had calcification in subependymal nodules. One patient did not have subependymal nodules. In this study group 12/20 patients had enlarged perivascular space. Although 9/20 had thin corpus callosum and 12/20 had enlarged ventricles, only one patient showed cerebral atrophy. Conclusion We observed that in our patients quantity of cortical tubers in parietal lobes were similar to frontal lobes. 2/20 (10%) patients showed tubers in cerebellum. 60% revealed enlarged perivascular spaces which may be interesting to study in larger groups of TS patients.
