In glutaric aciduria type I, an autosomal recessive disease of mitochondrial lysine, hydroxylysine and tryptophan catabolism, striatal lesions are characteristically induced by acute encephalopathic crises during a finite period of brain development (age 3-36 months). The frequency of striatal injury is significantly less in patients diagnosed as asymptomatic newborns by newborn screening. Most previous studies have focused on the onset and mechanism of striatal injury, whereas little is known about neuroradiological abnormalities in pre-symptomatically diagnosed patients and about dynamic changes of extrastriatal abnormalities. Thus, the major aim of the present retrospective study was to improve our understanding of striatal and extrastriatal abnormalities in affected individuals including those diagnosed by newborn screening. To this end, we systematically analysed magnetic resonance imagings (MRIs) in 38 patients with glutaric aciduria type I diagnosed before or after the manifestation of neurological symptoms. To identify brain regions that are susceptible to cerebral injury during acute encephalopathic crises, we compared the frequency of magnetic resonance abnormalities in patients with and without such crises. Major specific changes after encephalopathic crises were found in the putamen (P < 0.001), nucleus caudatus (P < 0.001), globus pallidus (P = 0.012) and ventricles (P = 0.001). Analysis of empirical cumulative distribution frequencies, however, demonstrated that isolated pallidal abnormalities did not significantly differ over time in both groups (P = 0.544) suggesting that isolated pallidal abnormalities are not induced by acute crises--in contrast to striatal abnormalities. The manifestation of motor disability was associated with signal abnormalities in putamen, caudate, pallidum and ventricles. In addition, we found a large number of extrastriatal abnormalities in patients with and without preceding encephalophatic crises. These abnormalities include widening of anterior temporal and sylvian CSF spaces, pseudocysts, signal changes of substantia nigra, nucleus dentatus, thalamus, tractus tegmentalis centralis and supratentorial white matter as well as signs of delayed maturation (myelination and gyral pattern). In contrast to the striatum, extrastriatal abnormalities were variable and could regress or even normalize with time. This includes widening of sylvian fissures, delayed maturation, pallidal signal changes and pseudocysts. Based on these results, we hypothesize that neuroradiological abnormalities and neurological symptoms in glutaric aciduria type I can be explained by overlaying episodes of cerebral alterations including maturational delay of the brain in utero, acute striatal injury during a vulnerable period in infancy and chronic progressive changes that may continue lifelong. This may have widespread consequences for the pathophysiological understanding of this disease, long-term outcomes and therapeutic considerations.
Glutaryl-CoA dehydrogenase (GCDH) deficiency is an autosomal recessive disease with an estimated overall prevalence of 1 in 100 000 newborns. Biochemically, the disease is characterized by accumulation of glutaric acid, 3-hydroxyglutaric acid, glutaconic acid, and glutarylcarnitine, which can be detected by gas chromatography-mass spectrometry of organic acids or tandem mass spectrometry of acylcarnitines. Clinically, the disease course is usually determined by acute encephalopathic crises precipitated by infectious diseases, immunizations, and surgery during infancy or childhood. The characteristic neurological sequel is acute striatal injury and, subsequently, dystonia. During the last three decades attempts have been made to establish and optimize therapy for GCDH deficiency. Maintenance treatment consisting of a diet combined with oral supplementation of L: -carnitine, and an intensified emergency treatment during acute episodes of intercurrent illness have been applied to the majority of patients. This treatment strategy has significantly reduced the frequency of acute encephalopathic crises in early-diagnosed patients. Therefore, GCDH deficiency is now considered to be a treatable condition. However, significant differences exist in the diagnostic procedure and management of affected patients so that there is a wide variation of the outcome, in particular of pre-symptomatically diagnosed patients. At this time of rapid expansion of neonatal screening for GCDH deficiency, the major aim of this guideline is to re-assess the common practice and to formulate recommendations for diagnosis and management of GCDH deficiency based on the best available evidence.
The recanalization rate of CSVT under OAC was high and the median time to CRec was 6 months. Thrombosis of the superior sagittal sinus is a positive predictor of recanalization. Outcome in this cohort was excellent but no significant association of outcome and recanalization status was found.
Background: To evaluate the effect of occlusion type and fibrinolytic agent on recanalization success and clinical outcome in patients undergoing local intra-arterial fibrinolysis (LIF) in acute hemispheric stroke. Methods: LIF was performed in 137 patients with angiographically established occlusion in the carotid circulation within 6 h of stroke onset. Retrospective analysis included recanalization success, recanalization time, type of occlusion and fibrinolytic treatment mode. Five types of occlusion were categorized: intracranial bifurcation (carotid ‘T’) of the internal carotid artery (ICA; n = 35); proximal segment of the middle cerebral artery (MCA; n = 66); distal segment of the MCA (n = 20); extracranial ICA with MCA embolism (n = 8); multiple peripheral branches of the anterior cerebral artery and the MCA (n = 8). Neurologic outcome was evaluated after 3 months by Barthel Index (BI) as good (BI >90), moderate (BI 50–90), poor (BI <50) or death. Results: Recanalization was achieved in 74 patients (54%). Mean recanalization time in recanalized patients was 91 min. Neurologic outcome was good in 48 patients (35%), moderate in 34 (25%), poor in 30 (22%) and 25 died (18%). Outcome was significantly better in recanalized than in nonrecanalized patients (p < 0.001). Treatment results were significantly better in proximal and distal MCA occlusion than in carotid ‘T’ occlusions (p < 0.001). Recanalization success hardly differed between urokinase and rt-PA. Combined treatment with rt-PA and lys-plasminogen tended toward a faster recanalization. Parenchymal hemorrhage occurred in 13 patients (9%). Conclusion: The type of occlusion is of high prognostic value for successful fibrinolysis in the anterior circulation. However, recanalization is a time-consuming process even with an intra-arterial approach. Recanalization did not differ between type or dosage of plasminogen activators. Further innovative attempts are warranted towards hastening recanalization time in endovascular acute stroke treatment.
This article summarizes the magnetic resonance imaging features of glutaric aciduria type I (GA I) based on the cases presented at the 3rd International Workshop on Glutaryl-CoA Dehydrogenase Deficiency together with a review of previously reported neuroimaging characteristics of GA I. Previous reports have focused on characteristic findings, such as basal ganglia injury and frontotemporal atrophy or hypoplasia, subdural effusions and white-matter disease. Most of these findings have been demonstrated in symptomatic children, i.e. after manifestation of acute encephalopathic crises. In contrast, prospective investigations in presymptomatically diagnosed children are rare. Since more recent investigations have highlighted CNS changes in patients without encephalopathic crises, systematic prospective investigations of neuroradiological findings in this disease are indispensable for a better understanding of this disease. Based on these findings a suggestion for a MRI protocol is presented, supporting a standardized evaluation of patients with GA I.
These patients' clinical signs and cranial MRI abnormalities are strikingly similar and may represent a distinctive disease with autosomal-recessive inheritance: cystic leukoencephalopathy without megalencephaly.
Quantitative 23Na magnetic resonance imaging (MRI) provides tissue sodium concentration (TSC), which is connected to cell viability and vitality. Long acquisition times are one of the most challenging aspects for its clinical establishment. K‐space undersampling is an approach for acquisition time reduction, but generates noise and artifacts. The use of convolutional neural networks (CNNs) is increasing in medical imaging and they are a useful tool for MRI postprocessing. The aim of this study is 23Na MRI acquisition time reduction by k‐space undersampling. CNNs were applied to reduce the resulting noise and artifacts. A retrospective analysis from a prospective study was conducted including image datasets from 46 patients (aged 72 ± 13 years; 25 women, 21 men) with ischemic stroke; the 23Na MRI acquisition time was 10 min. The reconstructions were performed with full dataset (FI) and with a simulated dataset an image that was acquired in 2.5 min (RI). Eight different CNNs with either U‐Net–based or ResNet‐based architectures were implemented with RI as input and FI as label, using batch normalization and the number of filters as varying parameters. Training was performed with 9500 samples and testing included 400 samples. CNN outputs were evaluated based on signal‐to‐noise ratio (SNR) and structural similarity (SSIM). After quantification, TSC error was calculated. The image quality was subjectively rated by three neuroradiologists. Statistical significance was evaluated by Student’s t‐test. The average SNR was 21.72 ± 2.75 (FI) and 10.16 ± 0.96 (RI). U‐Nets increased the SNR of RI to 43.99 and therefore performed better than ResNet. SSIM of RI to FI was improved by three CNNs to 0.91 ± 0.03. CNNs reduced TSC error by up to 15%. The subjective rating of CNN‐generated images showed significantly better results than the subjective image rating of RI. The acquisition time of 23Na MRI can be reduced by 75% due to postprocessing with a CNN on highly undersampled data.
Computed tomography perfusion and CTA provide an effective add-on to standard CT in acute stroke imaging by significantly increasing the sensitivity and reliability of infarct detection.
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