Browsing by Author "Schonstedt, Valeria"
Now showing 1 - 3 of 3
Results Per Page
Sort Options
Item Fibrolipomatous hamartoma and its ultrasound diagnosis: case series and review of the literature(Society of Radiologists in Ultrasound, 2014) Whittle, Carolina; Schonstedt, Valeria; Schiappacasse, GiancarloFibrolipomatous hamartoma is a benign tumor mainly affecting peripheral nerves. It is characterized by abnormal growth of fibroadipose tissue within the nerve, leading to progressive compressive neuropathies. Carpal tunnel syndrome is the most frequent among them. Although it is considered an infrequent tumor, magnetic resonance imaging use has led to an increase in case reports. We present 3 clinical cases of fibrolipomatous hamartoma consulting due to soft tissue mass, which were diagnosed by ultrasound.Item Morphometric analysis program: Detection of epileptic foci in young children using an adult normative database: Initial experience(2021) Stecher, Ximena; Schonstedt, Valeria; Manterola, Carla; Velásquez, Álvaro; Zamorano, Francisco; Carreño, Fernando; Castillo, MauricioObjective: To report our initial experience using an adult-template MAP in drugresistant focal epilepsy in five children with apparently normal MRI. Methods: Patients selected were highly suspicious of harboring focal structural lesions and had negative brain MRI studies. MAP was performed using a locally obtained adult database as a template. Results were reviewed by two neuroradiologists. Pertinence of MAP-positive areas was confirmed by the focal epileptic hypothesis or by pathology when possible (J Neuroradiol, 39, 2012, 87). Visual analysis was performed using Mango Software. MRI studies were reanalyzed at the workstation with knowledge of the clinical suspicion to confirm or discard the possibility of FCD. Results: Five patients aged 19-48 months were studied, all with initial 3T MRI studies interpreted as normal. All had focal epileptic hypothesis with coherence of clinical seizure characterization and electroencephalographic findings. In two patients, histology showed type 1 FCD. Due to the age of our subjects, the junction map always highlighted the subcortical white matter in relationship to maturity differences. FCD was identified as asymmetric U-shaped highlighted regions in the junction map. Significance: FCD is the most frequent pathology reported in pediatric epilepsy surgery series (Epileptic Disord, 18, 2016, 240). Significant number of FCDs may be overlooked on MRIs, reducing the odds of seizure freedom after surgery (Epilepsy Res, 89, 2010, 310). MAP is an image postprocessing method for enhanced visualization of FCD; however, when using an adult template in developing brains, normal subcortical regions may be highlighted as pathological. Creating a pediatric template is difficult, due to the need for general anesthesia to acquire the MRI database. Here, we were able to show that MAP identified FCDs as asymmetric “U-” shaped highlighted regions in the junction maps of all five patients, which may indicate that obtaining childhood databases for this purpose may not be necessary and that adult ones suffice for diagnosis of FCD.Item Vigabatrin-induced MRI changes associated with extrapyramidal symptoms in a child with infantile spasms(Sage Publications, 2015) Schonstedt, Valeria; Stecher, Ximena; Venegas, Viviana; Silva, ClaudioVigabatrin is an antiepileptic drug used for treatment of infantile spasms. We present a female patient with infantile spasms in treatment with vigabatrin who developed ataxic movements. MRI demonstrated a symmetrical pattern of thalamic and globi pallidi diffusion restriction. While these image features have been widely described to be related to the use of vigabatrin, this case highlights the development of movement disorders in association with MRI signal changes. Awareness of the reversible nature of this condition is reassuring for the treating team and avoids unjustified studies.