Hippocampal volumes were corrected for individual brain (supratentorial) volumes, and corrected hippocampal volumes smaller than 2 SDs (absolute value and/or asymmetry index, defined by the ratio of the smaller over the larger hippocampus of each individual) from the mean of controls were considered as having atrophy. 2012). CLINCIAL The histopathology of HS is characterized by loss of specific neurons and synaptic reorganization of surviving cells,5 and in MR images, this is observed as volume reduction and signal hyperintensity in T2 images.6,7 Quantification of hippocampal volume has advantages over visual analysis for the detection of subtle and bilateral hippocampal abnormalities.2,8 Equally, the quantification of hippocampal T2 signal, especially with relaxometry, can improve the MR imaging diagnosis of HS.9,10 Both volume and hippocampal signal quantification measurements have good correlation with histopathologic findings of HS.4, Currently, these techniques are considered reliable and reproducible for the detection of hippocampal pathology.11 However, hippocampal volumetry by manual segmentation is time-consuming and depends on the expertise of the examiner. Corrected volume of the left hippocampus: 3.50 cm3 (z score = −2.20 SDs). Last updated: 6/9/2020 Landmark at nasion/glabella (±50mm), you must re-landmark in the brain if another body part is scanned first. Detailed imaging parameters can be found elsewhere (Wang, et al. A, A 67-year-old male patient, with MTLE and left EEG seizure focus. Classic signs of HS were as follows: reduction of volume and abnormal shape observed on T1 images and increased signal observed in T2 and FLAIR images. Never use an open MRI for MTBI. Bookmerilab helps you in saving up to Rs. In a study of 40 consecutively registered patients with medically refractory focal epilepsy, 65% of patients (15 of 23) with normal findings at 1.5-T standard head coil brain MRI had new findings at 3-T eight-channel phased-array brain MRI. Scanner preference: 3T only. Ana C. Coan was responsible for the study concept and design, patient selection and recruitment, MRI visual analysis, interpretation of the data, and manuscript writing. Use all motion reduction techniques except changing scan parameters, Surgical resections, shunts, metal (some are not compatible), Put saline bags on either side of patient's head, Can be ± 50mm from Nasion - should be as close as possible in all 3 planes, Re - landmark, if C-spine was done first as part of a double study, Echo test failure – call your network admin, Delete incorrect series from queue monitor, Extend slice coverage 1-2 mm beyond the skin margin, not necessarily to cover the ears. Volumetry detected bilateral hippocampal atrophy in 9 patients (8 with visual signs of HS and 1 with visually normal MR imaging findings). Hyperoxia (oxygen enhancement, OE) was carried out by administering 100% O(2) in epochs by mask or cannula interleaved with breathing of normal atmospheric air. Hippocampal volume assessment in temporal lobe epilepsy: how good is automated segmentation? However, this addition would add time to the procedure and would probably result in limited improvement in the detection rate (<1%). Here we demonstrated that with 3T MRI, adequate epilepsy protocols, and expert visual evaluation, quantification analysis can still improve the detection of subtle signs of HS in 28% of patients. We do not capture any email address. With quantitative analysis of 1.5T MRI, a group of patients with MTLE remains with no detectable structural abnormalities even when HS is confirmed after surgical removal of the mesial temporal structures.22 For patients with drug-resistant MTLE and normal MR imaging findings, invasive procedures, which have high cost and morbidity, are often necessary to evaluate the potential target for surgical intervention,23 and yet for these individuals, the rate of seizure freedom is lower than that for those with MRI signs of HS.24,25 Histopathology of HS is only found in a limited number of patients with MTLE with normal MR imaging findings undergoing surgery, but those with positive hippocampal pathology are the ones with better surgical outcomes.24,26 It is necessary to improve noninvasive techniques that could more efficiently select the individuals with MTLE with subtle HS to better select surgical patients and improve outcomes. MATERIALS AND METHODS: Two hundred three patients with mesial temporal lobe epilepsy defined by clinical and electroencephalogram criteria had 3T MRI visually analyzed by imaging epilepsy experts. T2 relaxometry in Aftervoxel software. In our series, only 1 patient with visual signs of HS had normal volumetry and signal quantification. MRI epilepsy protocol refers to the sequence of images taken of the brain when evaluating a potential seizure disorder. For this analysis, a region of interest was manually defined in 3 different MR imaging sections, including the hippocampus of each individual (1 in the head, 1 in the body, and 1 in the tail of the hippocampus) by an investigator blinded to the results of the MR imaging visual evaluation (B.K.). References 1 Bradley WG, Waluch V, Yadley RA, Wycoff RR. My seizures were better controlled; I was used to them; but I still wanted to know. Acquisition protocols are proposed for the main MRI devices. His seizures started at 11 years of age and were characterized by an aura described as fear and an epigastric sensation followed by loss of consciousness and manual automatisms. Andrea Bernasconi, MD. In patients who had bilateral hippocampal abnormalities detected by the quantifications methods, there was marked asymmetry. In the remaining 4 patients, 2 had bilateral asymmetric hippocampal abnormalities on visual analyses and the relaxometry lateralized to the side with less hippocampal atrophy by both visual and automatic volumetry, and the other 2 patients had unilateral hippocampal atrophy (concordant by visual and automatic volumetry) and the relaxometry lateralized to the side contralateral to the atrophy and hyperintense T2 signal defined by visual analysis. On the right side of the graphic are shown the hippocampal volumes of patients (white circles = hippocampi ipsilateral to the epileptic focus; mean volume, 3.78 ± 0.51 cm3; black triangles = hippocampi contralateral to the epileptic focus; mean volume, 4.28 3± 0.56 cm). The side of the HS detected by MR imaging visual and volumetry analysis was concordant in all except 1 case (118/119, 99%). While best practices do exist, protocol design varies according to factors that include: The needs of the patient and the specifics of the symptoms and case; The MRI equipment being used In the remaining 4% (5/117), the MR imaging signs of HS were bilateral and symmetric. On the right side of the graphic is the hippocampal T2 signal of patients (white circles = hippocampi ipsilateral to the epileptic focus; mean signal, 105.49 ± 7.88; black triangles = hippocampi contralateral to the epileptic focus; mean signal, 99.10 ± 5.01). Spacing – 1.2 mm8. Epilepsy protocol MRI at 1.5T or 3.0T, on the other hand, includes the entire brain from nasion to inion, T1-weighted MPRAGE or SPGR images 1.5-mm slice thickness with no intervening gap obtained in the coronal oblique plane (if TLE is suspected). We think that this optimized hippocampal quantification protocol can be easily applied to all patients with drug-resistant focal epilepsies as a parallel and additional analysis for the routine evaluation of MRI in specialized epilepsy centers. NEX / NSA – 16. MRI protocol for epilepsy is a group of MRI sequences put together to improve sensitivity and specificity in identifying possible structural abnormalities that underlie seizure disorders (e.g. Hippocampal signal values higher than 2 SDs from the mean of the control group composed of the same individuals in the volumetry analysis (absolute value and/or asymmetry index, defined by the ratio of higher and lower hippocampal signals of each individual) were considered hyperintense signal. His seizures started at 5 years of age and were characterized by an aura described as jamais vu followed by a hipometer complex partial seizure. Check the positioning block in the other two planes. Dr Cendes received support from Conselho Nacional de Desenvolvimento Científico e Tecnológico, Brazil.