T2 hyperintense signal of the central tegmental tracts in children: disease or normal maturational process?

Primary glioblastoma multiforme tumors of the medulla oblongata are rare, especially in the adult population. Perhaps due to this rarity, we are not aware of any previous reports addressing the resection of these tumors or their clinical outcomes.In this surgical video, we present a 43-year-old man with a 1-month history of left-sided paresthesia. The paresthesia initiated in the left hand, along with weakness and reduced fine motor control, and then spread to the entire left side of the body. He had recent weight loss, imbalance, difficulty in swallowing, and hoarseness in his voice. He also had a diminished gag reflex, and significant atrophy of the right side of the tongue with an accompanying deviation of the uvula and fasciculations of the tongue. MRI showed an infiltrative expansile mass within the medulla with peripheral enhancement and central necrosis. In T2/FLAIR sequences, a hyperintense signal extended superiorly into the left inferior aspect of the pons and left inferior cerebellar peduncle and inferiorly into the upper cervical cord.The decision was made to proceed with surgical resection. The patient underwent a midline suboccipital craniotomy with C1 laminectomy for surgical resection of this infiltrative expansile intrinsic mass in the medulla oblongata, with concurrent monitoring of motor and somatosensory evoked potentials and monitoring of lower cranial nerves IX, X, XI, and XII. A gross-total resection of the enhancing portion of the tumor was performed, along with a subtotal resection of the nonenhancing portion. The surgery and postoperative course were uneventful. Histopathology revealed a grade IV astrocytoma. The patient received radiation therapy.In this surgical video, we demonstrate important steps for the microsurgical resection of this challenging glioblastoma multiforme of the medulla oblongata.The video can be found here: https://youtu.be/QHbOVxdxbeU.

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Fascicular torsions of the anterior and posterior interosseous nerve in 4 cases: neuroimaging methods to improve diagnosis

Journal of Neurosurgery ◽

10.3171/2019.3.jns183302 ◽

2020 ◽

Vol 132 (6) ◽

pp. 1925-1929 ◽

Cited By ~ 3

Author(s):

Jennifer Kollmer ◽

Paul Preisser ◽

Martin Bendszus ◽

Henrich Kele

Keyword(s):

Magnetic Resonance ◽

Surgical Intervention ◽

Case Series ◽

Diagnostic Methods ◽

Posterior Interosseous Nerve ◽

Nerve Ultrasound ◽

Magnetic Resonance Neurography ◽

Surgical Exploration ◽

Hyperintense Signal ◽

Emergency Surgical Intervention

Diagnosis of spontaneous fascicular nerve torsions is difficult and often delayed until surgical exploration is performed. This case series raises awareness of peripheral nerve torsions and will facilitate an earlier diagnosis by using nerve ultrasound (NUS) and magnetic resonance neurography (MRN). Four patients with previously ambiguous upper-extremity mononeuropathies underwent NUS and 3T MRN. Neuroimaging detected proximal torsions of the anterior and posterior interosseous nerve fascicles within median or radial nerve trunks in all patients. In NUS, most cases presented with a thickening of affected nerve fascicles, followed by an abrupt caliber decrease, leading to the pathognomonic sausage-like configuration. MRN showed T2-weighted hyperintense signal alterations of fascicles at and distal to the torsion site, and directly visualized the distorted nerves. Three patients had favorable outcomes after being transferred to emergency surgical intervention, while 1 patient with existing chronic muscle atrophy was no longer eligible for surgery. NUS and MRN are complementary diagnostic methods, and both can detect nerve torsions on a fascicular level. Neuroimaging is indispensable for diagnosing fascicular nerve torsions, and should be applied in all unclear cases of mononeuropathy to determine the diagnosis and if necessary, to guide surgical therapies, as only timely interventions enable favorable outcomes.

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Challenges in Diagnosing Intermediate Maple Syrup Urine Disease by Newborn Screening and Functional Validation of Genomic Results Imperative for Reproductive Family Planning

International Journal of Neonatal Screening ◽

10.3390/ijns7020025 ◽

2021 ◽

Vol 7 (2) ◽

pp. 25

Author(s):

Mona Sajeev ◽

Sharon Chin ◽

Gladys Ho ◽

Bruce Bennetts ◽

Bindu Parayil Sankaran ◽

...

Keyword(s):

Newborn Screening ◽

Maple Syrup Urine Disease ◽

Dietary Intervention ◽

Brain Mri ◽

Prenatal Testing ◽

Intermediate Form ◽

Motor Delay ◽

Maple Syrup ◽

Hyperintense Signal ◽

Urine Disease

Maple syrup urine disease is caused by a deficiency of branched-chain alpha-ketoacid dehydrogenase, responsible for degradation of leucine, isoleucine, and valine. Biallelic pathogenic variants in BCKDHA, BCKDHB, or DBT genes result in enzyme deficiency. We report the case of a female infant who presented with mild gross motor delay at 4 months, and seizures with hypoglycaemia at 5 months. Newborn screening returned total leucine/isoleucine at the 99.5th centile of the population; however, as second-tier testing reported minimal alloisoleucine, the results were considered inconsistent with MSUD. Plasma amino acid and urine organic acid analyses at 5 months were, however, consistent with a diagnosis of MSUD. A brain MRI showed bilateral symmetrical T2 hyperintense signal abnormalities involving white matter, globus pallidus, thalamus, brainstem, and dentate nuclei with restricted diffusion. A repeat MRI 10 months post-dietary-intervention showed the resolution of these changes and progression in myelination. Her clinical phenotype, including protein tolerance, correlated with intermediate MSUD. Molecular analysis of all three genes identified two variants of uncertain significance, c.434-15_434-4del and c.365A>G (p. Tyr122Cys) in the DBT gene. The rate of leucine decarboxylation in fibroblasts was reduced, but not to the extent observed in classical MSUD patients, supporting an intermediate form of MSUD. Previously reported mRNA splicing studies supported a deleterious effect of the c.434-15_434-4del variant. This functional evidence and confirmation that the variants were in trans, permitted their reclassification as pathogenic and likely pathogenic, respectively, facilitating subsequent prenatal testing. This report highlights the challenges in identifying intermediate MSUD by newborn screening, reinforcing the importance of functional studies to confirm variant pathogenicity in this era of molecular diagnostics.

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Evaluation of the Swallow-Tail Sign and Correlations of Neuromelanin Signal with Susceptibility and Relaxations

Tomography ◽

10.3390/tomography7020010 ◽

2021 ◽

Vol 7 (2) ◽

pp. 107-119

Author(s):

Tzu-Wei Lee ◽

Cheng-Yu Chen ◽

Kuan Chen ◽

Chao-Wei Tso ◽

Hui-Hsien Lin ◽

...

Keyword(s):

Magnetization Transfer ◽

Systematic Evaluation ◽

Joint Analysis ◽

Quantitative Susceptibility Mapping ◽

Widespread Application ◽

Hyperintense Signal ◽

Significant Difference ◽

Relaxation Measurements ◽

Iron Deposits ◽

Older Subjects

The presence of a swallow-tail sign in the nigrosome-1 with hyperintense signal shown on the susceptibility-weighted imaging (SWI) has been shown to be sensitive in detecting the abnormal iron deposits in this area. A systematic evaluation in healthy subjects is required before this tool can be recommended in a widespread application. We evaluated a simple and practical SWI approach using a multiecho gradient-echo sequence with an improved contrast-to-noise ratio (CNR). We also evaluated the association of the neuromelanin imaging contrast behavior with the susceptibility and relaxation measurements. Twenty-five older and 23 young healthy adults were evaluated. The CNRs of the nigrosome-1 were compared along with method and group. Correlations of the nigrosome-1 neuromelanin signal in the neuromelanin-sensitive imaging with CNRs in the susceptibility, T1 and T2 mappings were examined. Two different coils were used to confirm the reproducibility. Compared with the single-echo, multiecho SWI can improve the CNR of the swallow-tail sign. We found significant correlations between neuromelanin signal and CNRs in the susceptibility and T2 mappings, and T1 value. The older subjects exhibited increased CNRs compared with the young adults. No significant difference was observed in the measurements between 20 and 64 channels. The multiecho technique allows the high-quality nigrosome-1 images in SWI and allows for a joint analysis of T2* and quantitative-susceptibility mapping at high spatial resolution. The correlations of neuromelanin-sensitive imaging with susceptibility and T2 imply that the iron content in the nigrosome-1 may have significant influences on the hyperintensity of neuromelanin in the magnetization transfer-related contrast.

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Imaging features of hemangioma in long tubular bones

BMC Musculoskeletal Disorders ◽

10.1186/s12891-020-03882-2 ◽

2021 ◽

Vol 22 (1) ◽

Author(s):

Lei Cao ◽

Jin-Xu Wen ◽

Shu-Man Han ◽

Hui-Zhao Wu ◽

Zhi-Gang Peng ◽

...

Keyword(s):

Soft Tissue ◽

Plain Radiograph ◽

Ground Glass Opacity ◽

Plain Radiography ◽

Long Bone ◽

Imaging Features ◽

Mri Imaging ◽

Soft Tissue Density ◽

Tissue Density ◽

Hyperintense Signal

Abstract Background To investigate the imaging features of hemangiomas in long tabular bones for better diagnosis. Methods Twenty-four patients with long bone hemangiomas confirmed by pathology were enrolled. Nineteen patients had plain radiography, fourteen patients had computed tomography (CT) and eleven had magnetic resonance imaging (MRI). The hemangioma was divided into medullary [13], periosteal [6] and intracortical type [5]. Results Among 19 patients with plain radiography, eleven patients were medullary, three periosteal, and five intracortical. In the medullary type, the lesion was primarily osteolytic, including five cases with irregular and unclear rims and one lesion having osteosclerotic and unclear rims. In three patients with the periosteal type, the lesion had clear rims with involvement of the cortical bone in the form of bone defect, including two cases with local thickened bone periosteum and one case having expansile periosteum. Five intracortical hemangiomas had intracortical osteolytic lesions with clear margins. Among 14 patients with CT imaging, 8 cases were medullary, three periosteal, and three intracortical. Among 8 medullary hemangiomas, one had ground glass opacity, and seven had osteolytic, expansile lesions like soft tissue density with no calcification. In three periosteal cases, the lesion was osteolytic with thickened periosteum and narrowed medullary cavity. In three intracortical hemangiomas, the lesion was of even soft tissue density with no calcification. Among 11 patients with MRI imaging, seven were medullary, two periosteal, and two intracortical. Among 7 medullary lesions, six were of hypointense signal on T1WI and hyperintensesignal on T2 WI. In two periosteal cases, the periosteum was thickened, with one case being of equal signal, and the other having no signal. Two intracortical hemangiomas were both of slightly low signal on T1WI but hyperintense signal on T2WI. Conclusions The long bone hemangiomas had characteristic cystic honeycomb-like presentations in plain radiograph. CT and MRI imagings are helpful for diagnosis of hemangiomas in long bone.

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Treating ischaemic stroke with intravenous tPA beyond 4.5 hours under the guidance of a MRI DWI/T2WI mismatch was safe and effective

Stroke and Vascular Neurology ◽

10.1136/svn-2018-000186 ◽

2019 ◽

Vol 4 (1) ◽

pp. 8-13 ◽

Cited By ~ 1

Author(s):

Qing-ke Bai ◽

Zhen-guo Zhao ◽

Lian-jun Lu ◽

Jian Shen ◽

Jian-ying Zhang ◽

...

Keyword(s):

Ischaemic Stroke ◽

Contrast Material ◽

Final Analysis ◽

National Institutes Of Health ◽

Haemorrhagic Transformation ◽

Intravenous Tissue Plasminogen Activator ◽

Hyperintense Signal ◽

Rapid Sequence ◽

Tissue Plasminogen ◽

Sequence Study

PurposeClinical trials have provided evidence that treating patients with acute ischaemic stroke (AIS) beyond 4.5 hours was feasible. Among them using MRI diffusion-weighted imaging/fluid attenuation inversion response (DWI/FLAIR) mismatch to guide intravenous tissue plasminogen activator (tPA) was successful. Our study explored the outcome and safety of using DWI/T2-weighted imaging (T2WI) mismatch to guide intravenous tPA therapy for patients with AIS between 4.5 hours and 12 hours of onset.MethodThis was a retrospective study. Records of 1462 AIS patients with the time of onset of <12 hours were reviewed. Those had MRI rapid sequence study and had hyperintense signal on DWI but normal T2WI and received intravenous tPA up to 12 hours of onset were included in the analysis. Their demographics, risk factors, post-tPA complications, National Institutes of Health Stroke Scale (NIHSS) scores and outcome were recorded and analyse. χ2 was used to compare the intergroup variables. SAS was used to perform statistical calculation. A p<0.05 was considered statistically significant.ResultsOf 1462 identified, 601 (41%) patients were entered into the final analysis. Among them, 327 (54%) had intravenous tPA within 4.5 hours of onset and 274 (46%) were treated between 4.5–12 hours. After intravenous tPA, 426 cases (71%) had >4 pints of improvement on NIHSS score within 24 hours. Postintravenous tPA, 32 (5.32%) cases had haemorrhagic transformation. 26 (4.33%) were asymptomatic ICH and 4 (0.67%) died. At 90 days, 523 (87%) achieved a modified Rankin scale of 0–2.ConclusionUsing MRI DWI/T2WI mismatch to identify patients with AIS for intravenous tPA between 4.5 hours and 12 hours was safe and effective. The outcome was similar to those used DWI/PWI or DWI/FLAIR mismatch as the screening tool. However, obtaining DWI/T2WI was faster and avoided the need of contrast material.

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Leukoencephalopathy due to variants in GFPT1-associated congenital myasthenic syndrome

Neurology ◽

10.1212/wnl.0000000000006886 ◽

2019 ◽

Vol 92 (6) ◽

pp. e587-e593 ◽

Cited By ~ 1

Author(s):

Guy Helman ◽

Suvasini Sharma ◽

Joanna Crawford ◽

Bijoy Patra ◽

Puneet Jain ◽

...

Keyword(s):

Genome Sequencing ◽

Muscle Weakness ◽

Genetic Diagnosis ◽

Clinical Information ◽

Congenital Myasthenic Syndrome ◽

Cerebral White Matter ◽

Repetitive Nerve Stimulation ◽

Hyperintense Signal ◽

Biological Parents ◽

Hexosamine Biosynthesis

ObjectiveTo determine the molecular etiology of disease in 4 individuals from 2 unrelated families who presented with proximal muscle weakness and features suggestive of mitochondrial disease.MethodsClinical information and neuroimaging were reviewed. Genome sequencing was performed on affected individuals and biological parents.ResultsAll affected individuals presented with muscle weakness and difficulty walking. In one family, both children had neonatal respiratory distress while the other family had 2 children with episodic deteriorations. In each family, muscle biopsy demonstrated ragged red fibers. MRI was suggestive of a mitochondrial leukoencephalopathy, with extensive deep cerebral white matter T2 hyperintense signal and selective involvement of the middle blade of the corpus callosum. Through genome sequencing, homozygous GFPT1 missense variants were identified in the affected individuals of each family. The variants detected (p.Arg14Leu and p.Thr151Lys) are absent from population databases and predicted to be damaging by in silico prediction tools. Following the genetic diagnosis, nerve conduction studies were performed and demonstrated a decremental response to repetitive nerve stimulation, confirming the diagnosis of myasthenia. Treatment with pyridostigmine was started in one family with favorable response.ConclusionsGFPT1 encodes a widely expressed protein that controls the flux of glucose into the hexosamine-biosynthesis pathway that produces precursors for glycosylation of proteins. GFPT1 variants and defects in other enzymes of this pathway have previously been associated with congenital myasthenia. These findings identify leukoencephalopathy as a previously unrecognized phenotype in GFPT1-related disease and suggest that mitochondrial dysfunction could contribute to this disorder.

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The T1W Hyperintense Signal on the Surface of Distal Segment of Bile Duct Tumor Thrombi and Its Significance

Academic Radiology ◽

10.1016/j.acra.2012.05.001 ◽

2012 ◽

Vol 19 (9) ◽

pp. 1141-1148

Author(s):

Qing-Yu Liu ◽

Hai-Gang Li ◽

Ming Gao ◽

Wei-Dong Zhang ◽

Xiao-Feng Lin

Keyword(s):

Bile Duct ◽

Distal Segment ◽

Bile Duct Tumor ◽

Hyperintense Signal ◽

Tumor Thrombi

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Optic pathway glioma infiltrating into somatostatinergic pathways in a young boy with gigantism

Journal of Neurosurgery ◽

10.3171/jns.1994.81.4.0595 ◽

1994 ◽

Vol 81 (4) ◽

pp. 595-600 ◽

Cited By ~ 13

Author(s):

Thomas J. Manski ◽

Charles S. Ha worth ◽

Bertrand J. Duval-Arnould ◽

Elisabeth J. Rushing

Keyword(s):

Magnetic Resonance Imaging ◽

Magnetic Resonance ◽

Optic Pathway Glioma ◽

Optic Pathway ◽

Resonance Imaging ◽

Content Type ◽

Hyperintense Signal ◽

Immunocytochemical Studies ◽

Stereotactic Biopsies ◽

Fine Print

✓ The authors report gigantism in a 16-month-old boy with an extensive optic pathway glioma infiltrating into somatostatinergic pathways, as revealed by magnetic resonance imaging and immunocytochemical studies. Stereotactic biopsies of areas showing hyperintense signal abnormalities on T2-weighted images in and adjacent to the involved visual pathways provided rarely obtained histological correlation of such areas. The patient received chemotherapy, which resulted in reduction of size and signal intensity of the tumor and stabilization of vision and growth velocity.

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What does a neuron learn from multisensory experience?

Journal of Neurophysiology ◽

10.1152/jn.00284.2014 ◽

2015 ◽

Vol 113 (3) ◽

pp. 883-889 ◽

Cited By ~ 14

Author(s):

Jinghong Xu ◽

Liping Yu ◽

Terrence R. Stanford ◽

Benjamin A. Rowland ◽

Barry E. Stein

Keyword(s):

Superior Colliculus ◽

Early Life ◽

Life Experience ◽

Sensory Experience ◽

Rearing Environment ◽

Early Life Experience ◽

Environmental Events ◽

Cat Superior Colliculus ◽

Maturational Process ◽

Multisensory Experience

The brain's ability to integrate information from different senses is acquired only after extensive sensory experience. However, whether early life experience instantiates a general integrative capacity in multisensory neurons or one limited to the particular cross-modal stimulus combinations to which one has been exposed is not known. By selectively restricting either visual-nonvisual or auditory-nonauditory experience during the first few months of life, the present study found that trisensory neurons in cat superior colliculus (as well as their bisensory counterparts) became adapted to the cross-modal stimulus combinations specific to each rearing environment. Thus, even at maturity, trisensory neurons did not integrate all cross-modal stimulus combinations to which they were capable of responding, but only those that had been linked via experience to constitute a coherent spatiotemporal event. This selective maturational process determines which environmental events will become the most effective targets for superior colliculus-mediated shifts of attention and orientation.

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