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BACKGROUND AND PURPOSE: There is a paucity of data regarding the incidence of structural brain lesions in children with new-onset unprovoked seizures. Our aim was to determine the frequencies and types of epileptogenic lesions detected on a dedicated epilepsy protocol MR imaging according to age group, the presence of developmental delay, and the number and types of seizures. MATERIALS AND METHODS: Consecutive children between 6 months and 18 years of age with new-onset unprovoked seizures were included. The frequencies and types of epileptogenic lesions were determined and then stratified according to sex, age groups, the presence of developmental delay, and the number and types of seizures at presentation. Multivariate analysis was used to identify variables significantly associated with the presence of epileptogenic lesions. RESULTS: One thousand children were included. An epileptogenic lesion was identified in 26%, with malformations of cortical development being the most common lesion (32%), followed by hypoxic-ischemic injury (20%) and vascular etiologies (16%). Univariate analysis showed a significant increase in the frequency of epileptogenic lesions with decreasing age, the presence of developmental delay, and the number and types of seizures at presentation. The presence of developmental delay and seizure type at presentation remained significant in a multivariate analysis. CONCLUSIONS: We documented a relatively high rate of epileptogenic lesions in children with new-onset seizures, with the presence of developmental delay and specific seizure types being associated with a higher likelihood of detecting an epileptogenic lesion on neuroimaging. This study fulfills the requirements of the study design recommended by the Practice Committee of the American Academy of Neurology, and we hope that our results will assist the relevant societies and committees in formulating neuroimaging guidelines for children with new-onset seizures.

Previous studies on possible accumulation of gadolinium-based contrast agents (GBCA) in the brain suggest that macrocyclic GBCA are less likely to accumulate than linear GBCA. However, conflicting results have been reported, especially in MS. The aim of this study is to investigate retrospectively the correlation between gadoterate-meglumine (macrocyclic GBCA) use and T1 signal intensity changes (SI) in the dentate nucleus and the GP on unenhanced T1-weighted images in a large cohort of MS patients.Unenhanced T1-weighted images of 232 MS patients who previously received multiple intravenous administrations of 0.1 mmol/kg of gadoterate-meglumine were reviewed. The change in T1 SI ratios of dentate nucleus/central pons (DN/CP) and globus pallidus/centrum semiovale (GP/CSO) was calculated between the first and last MRIs and correlated with age, number of injections, time interval between MRIs, disease duration, activity, and therapy.DN/CP ratio showed no significant changes whereas the GP/CSO ratio showed a significant decrease (p0.0001) between the first and last MRIs. Multivariable analyses of both ratios, controlling for age, disease duration, and time interval between MRIs, showed no significant correlation between the number of gadolinium injections and the differences in DN/CP (standardized beta = -0.018, p = 0.811) or GP/CSO SI ratios (standardized beta = -0.049, p = 0.499).Repeated administration of gadoterate-meglumine in MS patients did not result in increased T1 SI in the DN or the GP. The significant decrease of GP/CSO ratio between the first and last MRIs is not due to gadolinium accumulation but rather to varying MR parameters.

The regular administration of intrathecal chemotherapy has significantly reduced the risk of central nervous system leukemia in patients with acute lymphoblastic leukemia. We report the case of 28-year-old man who developed intrathecal methotrexate induced myelopathy; a rare but serious side effect of intrathecal chemotherapy. In the light of absent effective treatment strategies, description of the case, along with reviewing similar cases published in the literature will help shed a light on the possible pathophysiologic mechanisms behind this injury. To this date, there are no specific clinical, biochemical and imaging signs that would allow timely detection of intrathecal methotrexate induced myelopathy. This in turn is causing delayed treatment of this injury, resulting in significant morbidity and mortality.

To report the volumetric measures of the paralyzed vocal fold in patients undergoing injection laryngoplasty.All the medical records of patients with unilateral vocal fold paralysis who had high resolution computerized tomography scan of the neck and chest prior to injection laryngoplasty between October 2015 and May 2018 were included. Volumetric evaluation of the vocal folds was performed by measuring the vocal fold height using coronal images and the vocal fold length and width using axial images.A total of 21 patients divided into 13 males and 8 females were identified. The mean age was 56.66 Volumetric measurements of the paralyzed vocal fold in comparison to the normal vocal fold in a group of 21 patients with unilateral vocal fold paralysis shows the presence of significant difference between the normal and affected site, and the presence of large inter-subject variation. Information on the volume difference between the two vocal folds may be used to better estimate the amount that needs to be injected in medialization procedures.

The anatomical structure of the thalamus renders its segmentation on 3DT1 images harder due to its low tissue contrast, and not well-defined boundaries. We aimed to investigate the differences in the precision of publicly available segmentation techniques on 3DT1 images acquired at 1.5 T and 3 T machines compared to the thalamic manual segmentation in a pediatric population. Sixty-eight subjects were recruited between the ages of one and 18 years. Manual segmentation of the thalamus was done by three junior raters, and then corrected by an experienced rater. Automated segmentation was then performed with FSL Anat, FIRST, FreeSurfer, MRICloud, and volBrain. A mask of the intersections between the manual and automated segmentation was created for each algorithm to measure the degree of similitude (DICE) with the manual segmentation. The DICE score was shown to be highest using volBrain in all subjects (0.873 ± 0.036), as well as in the 1.5 T (0.871 ± 0.037), and the 3 T (0.875 ± 0.036) groups. FSL-Anat and FIRST came in second and third. MRICloud was shown to have the lowest DICE values. When comparing 1.5 T to 3 T groups, no significant differences were observed in all segmentation methods, except for FIRST (p = 0.038). Age was not a significant predictor of DICE in any of the measurements. When using automated segmentation, the best option in both field strengths would be the use of volBrain. This will achieve results closest to the manual segmentation while reducing the amount of time and computing power needed by researchers.

Diagnoses of thalamic atrophy in children are based on experts' judgments. No normative measures exist for aiding objective diagnoses. Our aim was to determine normative two-dimensions(2D) and volume measurements of the thalamus in normally developing children.MRI images of 245 patients were retrospectively collected. Only participants with normal brain MRIs were included in this cross-sectional study. Anterior-posterior (AP), transverse (T), and craniocaudal (C) diameters were measured. Volumetric masks of the thalamus were manually drawn, whereas volumetric measurements of the brain were automated.124 patients were male (50.6%). We tabulated our measurements from birth until 18 years old. No significant differences in the thalamus measurements are found between the two hemispheres nor between sexes. The most remarkable increase in the thalamus volume and AP dimension is noted in the first four years of life, following which the values seem to stabilize. Craniocaudal diameters seem to increase in the first year of life, whereas transverse diameters increase until the age of 14 before plateauing.We report normative values of the thalamus in 2D and 3D from birth until 18 years of age. A rapid increase in the thalamic size is noted during the first four years of life followed by stabilization.

Background and purpose The aim of this prospective study is to investigate and evaluate in clinical practice the diagnostic impact of 3DFLAIR in regards to 2DT2/PD in terms of infratentorial lesions detection in multiple sclerosis (MS). Material and methods 164 MS patients from the OFSEP database were reviewed retrospectively. MR examinations were performed on 1.5T or 3T systems from four different centers. Infratentorial lesions were counted and allocated to different regions of the posterior fossa by three raters independently (junior resident, resident with an expertise in neuroradiology, and senior neuro-radiologist) on the 3DFLAIR and 2DT2/PD. Both sequences do not have the same spatial resolution but reflect what is recommended by most of the consensus and done in clinical practice. Results With an overall number of 528 for Rater-1 and 798 for Rater-2 infratentorial lesions, 3DFLAIR had a significantly higher number of lesions detected than 2DT2/PD (303 for Rater-1 and 370 for Rater-2). The prevalence of trigeminal lesions detected by using 3DFLAIR was also significantly higher than 2DT2/PD. ROC analysis showed 3DFLAIR to be more specific and sensitive than 2DT2/PD. An overall difference between all three Raters has been observed. The more the Rater is experienced the more lesions he detects. Conclusion Along with the radiologist ability to detect lesions based on his level of experience, the OFSEP optimized 3DFLAIR can significantly improve infratentorial lesion detection in MS compared to 2DT2/PD. This is important in MS follow-up that takes into account new lesions number to adapt patients’ treatment.

BACKGROUND AND PURPOSE: Few articles in the literature have looked at the diameter of the optic nerve on MR imaging, especially in children, in whom observations are subjective and no normative data exist. The aim of this study was to establish a data base for optic nerve diameter measurements on MR imaging in the pediatric population. MATERIALS AND METHODS: This was a retrospective study on the MR imaging of pediatric subjects (younger than 18 years of age) at the Department of Diagnostic Radiology at the American University of Beirut Medical Center, Beirut, Lebanon. The optic nerve measurements were obtained by 3 raters on axial and coronal sections at 3 mm (retrobulbar) and 7 mm (intraorbital) posterior to the lamina cribrosa. RESULTS: Of 211 scans of patients (422 optic nerves), 377 optic nerves were measured and included. Ninety-four patients were female (45%) and the median age at MR imaging was 8.6 years (interquartile range, 3.9–13.3 years). Optic nerves were divided into 5 age groups: 0–6 months ( n = 18), 6 months–2 years ( n = 44), 2–6 years ( n = 86), 6–12 years ( n = 120), and 12–18 years ( n = 109). An increase in optic nerve diameter was observed with age, especially in the first 2 years of life. Measurements did not differ with eye laterality or sex. CONCLUSIONS: We report normative values of optic nerve diameter measured on MR imaging in children from birth to 18 years of age. A rapid increase in optic nerve diameter was demonstrated during the first 2 years of life, followed by a slower increase. This was independent of sex or eye laterality.

Pediatric ischemic stroke still represents a burden, and more than half of the survivors will experience cognitive or motor disabilities. The objective of this study was to investigate the role of thrombophilia in a cohort of children with arterial ischemic stroke. The records of infants and children with clinically and radiologically confirmed stroke were reviewed. Patients with venous or perinatal stroke were not included. Thirty-three patients were diagnosed with arterial ischemic stroke. The male/female ratio was 1.75:1. The median age was 4 years. The most frequent clinical manifestations were hemiparesis (54.5%) and seizures (33.3%). Genetic thrombophilia testing was available on 24 patients. Nine of the 24 patients (37.5%) were heterozygous for factor V Leiden. None of the patients carried the factor II G20210A variant. Ten patients (41.7%) were heterozygous and 3 (12.5%) were homozygous for methylenetetrahydrofolate reductase (MTHFR) C677T variant. Fifteen patients (62.5%) had one or more genetic polymorphism. Factor V Leiden was significantly associated with arterial ischemic stroke (P < 0.001). Stroke recurred in 2 children with multiple risk factors and MTHFR C677T mutation. Factor V Leiden is one of the major genetic risk factors for pediatric arterial ischemic stroke in Lebanon. MTHFR C677T was prevalent among patients with recurrent stroke.

We explore the safety, and therapeutic benefit of intrathecal injection of ex-vivo expanded autologous bone marrow derived mesenchymal stem cells (BM-MSCs) in 10 patients with advanced multiple sclerosis (MS). Patients were assessed at 3, 6 and 12 months. Assessment at 3-6 months revealed Expanded Disability Scale Score (EDSS) improvement in 5/7, stabilization in 1/7, and worsening in 1/7 patients. MRI at 3 months revealed new or enlarging lesions in 5/7 and Gadolinium (Gd+) enhancing lesions in 3/7 patients. Vision and low contrast sensitivity testing at 3 months showed improvement in 5/6 and worsening in 1/6 patients. Early results show hints of clinical but not radiological efficacy and evidence of safety with no serious adverse events.

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Background: Endoscopic third ventriculostomy (ETV) has gained wide popularity as a first-line treatment for obstructive hydrocephalus (OHC). We have been performing ETV since 1998. We report our experience with this technique in the management of OHC. Methods: Between 1998 and 2007, we performed 49 ETV procedures in 46 patients suffering from OHC. Medical records were retrospectively reviewed. Success was defined as shunt-free survival. Results: There were 29 males and 17 females with a mean age of 23 years (6 months–65 years). Aqueductal stenosis and tectal tumor were the most common etiologies (63%). Seven patients (15.6%) had early ETV failure. Of 38 patients with initial success and available follow-up, shunt independence was achieved in 29 patients (76.3%) after a mean follow-up of 37 months. Kaplan-Meier analysis yielded a 70% 5-year shunt-free survival rate. On multivariate analysis, no variables could predict early or late ETV failure. Transient complications occurred in 6 patients (13%), but there were no ETV-related deaths or permanent morbidity. Conclusion: ETV is a safe and effective treatment for OHC, resulting in a high rate of long-term shunt independence with a low risk of complications. ETV should be considered the treatment of choice for patients with OHC and its development as a substitute to shunt placement should be encouraged in neurosurgically developing countries.

Cervical aortic arch (CAA) is a rare congenital aortic anomaly. It can be associated with several cardiovascular abnormalities including aortic aneurysm, valvular disease, and pseudocoarctation. In this report, we present a case of CAA with combined association of both aneurysm formation and pseudocoarctation. This combination of anomalies is extremely uncommon, described in only 4 cases in the literature. In addition, our patient had an anomalous subaortic left brachiocephalic vein that, to our knowledge, was not previously described in the literature to be associated with CAA. The radiographic, multidetector computed tomography scan, and magnetic resonance angiography imaging findings are presented.

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Objective To determine the incidence of dehiscence between the vestibular aqueduct and the jugular bulb on computed tomography (CT) scans and assess its implication as a cause of dizziness or hearing loss. Methods Two hundred temporal bone CT scans were evaluated for the prevalence of dehiscence between the jugular bulb and vestibular aqueduct. Correlation of the imaging findings and clinical data was performed. Results A total of 11.5% of patients had dehiscence of the jugular bulb with the vestibular aqueduct; 75% of these cases occurred on the right side and in the setting of a high jugular bulb. Nine (39.1%) of 23 patients with dehiscence had dizziness, and 11 (47.8%) had hearing loss. The correlation between the incidence of dizziness, hearing loss, and dehiscence was not significant. Conclusion The incidence of a dehiscent jugular bulb with a vestibular aqueduct is 11.5%. The prevalences of vertigo and hearing loss associated with this finding are 39.1% and 47.8%, respectively. The depiction of dehiscent jugular bulb-vestibular aqueduct should be considered with caution as the sole cause of symptoms.

Objective To identify the relationship between the vertical portion of the facial nerve and the tympanic annulus, using computed tomographic (CT) scans of healthy adult and pediatric patients. Study design A retrospective review of CT scans. Setting The study was conducted in a tertiary referral medical center. Patients After excluding ears with noted pathology, a total of 241 ears were included in the final review (121 right and 120 left ears). The mean age of the patients was 33.3 years (2 mo to 87 yr). Intervention(s) Both structures were identified at three distinct locations: the superior and the inferior most margins of the tympanic ring and at the umbo. Measurements were made in both anteroposterior and a mediolateral planes. Comparisons between different age groups were made to analyze the relative change in position that happens with age. Results The vertical portion of the facial nerve, as it proceeds distally, takes a more anterior and lateral course, and crosses the plane of the annulus almost consistently in the inferior third. The average distance at each location is reported. Statistically significant differences were found between age groups, in the areas around the second genu and the distal most segment of the facial nerve. Conclusions This is the largest anatomic study to date analyzing the relationship of the facial nerve to the tympanic annulus. It also allows comparison between age groups, demonstrating a significant difference between adult and pediatric groups, especially in the distal portion of the fallopian canal.

The authors report a case of intraspinal neurenteric cyst in a 22-month-old child, who presented with acute paraplegia following a vesicourethrogram. Despite 8 days' delay in surgical decompression, he made a complete neurological recovery. Neurenteric cysts are rare congenital lesions of the spinal canal lined with an epithelium of endodermal origin. They are usually located at the cervicothoracic junction and present with progressive mild to moderate signs of myelopathy. This is a unique case in regard both to its clinical presentation and to the excellent outcome after 8 days of complete paraplegia.

We herein describe a 16-year-old child with acute lymphoblastic leukemia and acute pancreatitis who developed Wernicke's encephalopathy secondary to prolonged total parenteral nutrition (TPN) that lacked vitamin B1 supplementation. The patient showed a direct and complete response to thiamine therapy. Diagnostic challenges are discussed and recommendations for prophylactic vitamin B1 supplementation in children with leukemia who are placed on TPN are made.

We present the case of an 11-year-old boy with humoral immunodeficiency on monthly intravenous immunoglobulins (IVIG) infusions, evaluated for recurrent, brief, neurological deficits secondary to cerebral sinus thrombosis without any identifiable hypercoagulability state. Etiologic possibilities for the thrombotic event are presented with special discussion of IVIG-related cerebral thrombosis. To the best of our knowledge, our patient represents the first reported case of Bruton's disease on IVIG therapy developing a cerebral ischemic event and the second reported case of cerebral sinus thrombosis associated with IVIG use for any disease. Potential concerns regarding the risk of cerebral thrombosis during IVIG therapy in this and other disorders are reviewed.

A 30-year-old man who developed acute blurred vision in the right eye and right periocular pain on eye movement proved to have a bilateral optic neuropathy and imaging evidence suggestive of bilateral optic nerve sheath meningiomas. This is an unusual presentation for optic nerve meningioma but a reminder that this entity may mimic optic neuritis.

Acute appendicitis is one of the most common conditions requiring emergency surgery. However, acute appendicitis presenting with left lower quadrant abdominal pain is extremely rare. Imaging, particularly CT , plays an important role in establishing an accurate and prompt diagnosis, as delay in diagnosis may occur due to lack of uniformity in the clinical signs and symptoms. We report a rare case of a 10-year-old boy who presented with persistent left lower quadrant pain of several days duration, in which the CT scan of the abdomen and pelvis was essential in establishing the correct diagnosis. The malpositioned inflamed appendix was clearly identified in the left side of the abdomen, with the characteristic CT findings of uncomplicated intestinal malrotation. Left-sided acute appendicitis should be considered in the differential diagnosis of young patients presenting with left lower quadrant pain, in order to avoid delay in diagnosis and guide the surgical intervention.

Traumatic eye injuries are associated with significant visual impairment and are a major cause of monocular blindness. Rapid assessment and examination following trauma to the eye is crucial. A thorough knowledge of potential injuries is imperative to ensure rapid diagnosis, to prevent further damage to the eye, and to preserve visual capacity. One consequence of ocular trauma is cataract formation. We report a case and image of a 5-year-old boy who presented after sustaining a blunt head trauma. CT scan of the head revealed a markedly hypodense left eye lens.

Covert brain infarction is an emerging concern in patients with β-thalassemia intermedia (TI). We have recently observed a high prevalence (60%) of silent brain infarction on brain magnetic resonance imaging (MRI) in 30 splenectomized adults with TI. In this work, we further evaluate cerebral involvement in the same 30 patients using fluorodeoxyglucose positron emission tomography–computed tomography (PET-CT) scanning. The median age was 32 years (range, 18–54 years) with a male to female ratio of 13:17. Nineteen patients (63.3%) had evidence of decreased neuronal function on PET-CT. Involvement was mostly left sided, multiple, and most commonly in the temporal and parietal lobes. Elevated liver iron concentration, beyond 15 mg Fe/g dry weight, characterized patients with decreased neuronal function. The concordance rate between brain MRI and PET-CT for the detection of brain abnormality was only 36.7% (Kappa 0.056, P = 0.757), highlighting that both modalities reveal different types of brain pathology. Decreased neuronal function is a common finding in patients with TI and is associated with iron overload. Moreover, the addition of PET-CT to MRI identifies a greater proportion of TI patients with silent neuroimaging abnormalities.

BACKGROUND AND PURPOSE: Hereditary spastic paraplegia (HSP) is a disorder characterized by degeneration of the corticospinal tracts and posterior column of the spinal cord. Previously described radiologic findings included nonspecific brain abnormalities such as brain atrophy and white matter lesions, as well as atrophy of the spinal cord. In our study, we aimed to better characterize brain and spine MR imaging findings in a series of patients with HSP. MATERIALS AND METHODS: Nine patients from 4 different Lebanese families with the autosomal recessive form of HSP were included in the study. All patients underwent brain and whole-spine MR imaging. We assessed the presence of white matter abnormalities mainly along the corticospinal tracts, brain atrophy, thinning of the corpus callosum, and the presence of spinal cord atrophy or abnormal signal intensity. RESULTS: Imaging revealed mild brain atrophy (44%), atrophy of the corpus callosum (55%), white matter lesions (67%), abnormal T2 high signal intensity in the posterior limb of the internal capsule (55%), and mild spinal cord atrophy (33%). CONCLUSIONS: The MR imaging findings of HSP are nonspecific and variable; however, the most prominent features include atrophy of the corpus callosum, T2 signal intensity in the posterior limb of the internal capsule, and spinal cord atrophy.

Noninvasive diagnosis of brain lesions is important for the correct choice of treatment. Our aims were to investigate whether 1) proton MR spectroscopic imaging ((1)H-MRSI) can aid in differentiating between tumors and nonneoplastic brain lesions, and 2) perfusion MR imaging can improve the classification.We retrospectively examined 69 adults with untreated primary brain lesions (brain tumors, n = 36; benign lesions, n = 10; stroke, n = 4; demyelination, n = 10; and stable lesions not confirmed on pathologic examination, n = 9). MR imaging and (1)H-MRSI were performed at 1.5T before biopsy or treatment. Concentrations of N-acetylaspartate (NAA), creatine (Cr), and choline (Cho) in the lesion were expressed as metabolite ratios and were normalized to the contralateral hemisphere. Dynamic susceptibility contrast-enhanced perfusion MR imaging was performed in a subset of patients (n = 32); relative cerebral blood volume (rCBV) was evaluated. Discriminant function analysis was used to identify variables that can predict inclusion in the neoplastic or nonneoplastic lesion groups. Receiver operator characteristic (ROC) analysis was used to compare the discriminatory capability of (1)H-MRSI and perfusion MR imaging.The discriminant function analysis correctly classified 84.2% of original grouped cases (P.0001), on the basis of NAA/Cho, Cho(norm), NAA(norm), and NAA/Cr ratios. MRSI and perfusion MR imaging had similar discriminatory capabilities in differentiating tumors from nonneoplastic lesions. With cutoff points of NAA/Choor =0.61 and rCBVor =1.50 (corresponding to diagnosis of the tumors), a sensitivity of 72.2% and specificity of 91.7% in differentiating tumors from nonneoplastic lesions were achieved.These results suggest a promising role for (1)H-MRSI and perfusion MR imaging in the distinction between brain tumors and nonneoplastic lesions in adults.

Kearns-Sayre syndrome (KSS) is a mitochondrial disorder consisting of external ophthalmoplegia, retinitis pigmentosa, ataxia and heart block. Magnetic resonance imaging (MRI) shows abnormal T2 high signal intensity in the deep gray matter nuclei, the cerebellar and the subcortical white matter. We report an unusual MR pattern of KSS, where the T2 images revealed radially oriented, hypointense stripes in hyperintense white matter, a characteristic MRI pattern of lysosomal disease not previously reported in KSS.

Purpose To investigate whether in vivo proton magnetic resonance spectroscopic imaging (MRSI) can differentiate between 1) tumors and nonneoplastic brain lesions, and 2) high- and low-grade tumors in children. Materials and Methods Thirty-two children (20 males and 12 females, mean age = 10 ± 5 years) with primary brain lesions were evaluated retrospectively. Nineteen patients had a neuropathologically confirmed brain tumor, and 13 patients had a benign lesion. Multislice proton MRSI was performed at TE = 280 msec. Ratios of N-acetyl aspartate/choline (NAA/Cho), NAA/creatine (Cr), and Cho/Cr were evaluated in the lesion and the contralateral hemisphere. Normalized lesion peak areas (Chonorm, Crnorm, and NAAnorm) expressed relative to the contralateral hemisphere were also calculated. Discriminant function analysis was used for statistical evaluation. Results Considering all possible combinations of metabolite ratios, the best discriminant function to differentiate between nonneoplastic lesions and brain tumors was found to include only the ratio of Cho/Cr (Wilks' lambda, P = 0.012; 78.1% of original grouped cases correctly classified). The best discriminant function to differentiate between high- and low-grade tumors included the ratios of NAA/Cr and Chonorm (Wilks' lambda, P = 0.001; 89.5% of original grouped cases correctly classified). Cr levels in low-grade tumors were slightly lower than or comparable to control regions and ranged from 53% to 165% of the control values in high-grade tumors. Conclusion Proton MRSI may have a promising role in differentiating pediatric brain lesions, and an important diagnostic value, particularly for inoperable or inaccessible lesions. J. Magn. Reson. Imaging 2006. Published 2005 Wiley-Liss, Inc.