BACKGROUND: Idiopathic acute transverse myelitis (IATM) is a focal inflammatory disorder of the spinal cord that results in motor, sensory, and autonomic dysfunction. However, the comparative analysis of MRI-negative and MRI-positive in IATM patients were rarely reported.
OBJECTIVE: The purpose of this study was to compare MRI-negative with MRI-positive groups in IATM patients, analyze the predictors for a poor prognosis, thus explore the relationship between MRI-negative and prognosis.
METHODS: We selected 132 patients with first-attack IATM at the First Affiliated Hospital of Nanchang University from May 2018 to May 2022. Patients were divided into MRI-positive and MRI-negative group according to whether there were responsible spinal MRI lesions, and good prognosis and poor prognosis based on whether the EDSS score ≥ 4 at follow-up. The predictive factors of poor prognosis in IATM patients was analyzed by logistic regression models.
RESULTS: Of the 132 patients, 107 first-attack patients who fulfilled the criteria for IATM were included in the study. We showed that 43 (40%) patients had a negative spinal cord MRI, while 27 (25%) patients were identified as having a poor prognosis (EDSS score at follow-up ≥ 4). Compared with MRI-negative patients, the MRI-positive group was more likely to have back/neck pain, spinal cord shock and poor prognosis, and the EDSS score at follow-up was higher. We also identified three risk factors for a poor outcome: absence of second-line therapies, high EDSS score at nadir and a positive MRI result.
CONCLUSIONS: Compared with MRI-negative group, MRI-positive patients were more likely to have back/neck pain, spinal cord shock and poor prognosis, with a higher EDSS score at follow-up. The absence of second-line therapies, high EDSS score at nadir, and a positive MRI were risk factors for poor outcomes in patients with first-attack IATM. MRI-negative patients may have better prognosis, an active second-line immunotherapy for IATM patients may improve clinical outcome.

OBJECTIVE: To describe the association between preoperative ictal scalp electroencephalogram (EEG) results and surgical outcomes in patients with focal epilepsies.
METHODS: The data of consecutive patients with focal epilepsies who received surgical treatments at our center from January 2012 to December 2021 were retrospectively analyzed.
RESULTS: Our data showed that 44.2% (322/729) of patients had ictal EEG recorded on video EEG monitoring during preoperative evaluation, of which 60.6% (195/322) had a concordant ictal EEG results. No significant difference of surgery outcomes between patients with and without ictal EEG was discovered. Among MRI-negative patients, those with concordant ictal EEG had a significantly better outcome than those without ictal EEG (75.7% vs. 43.8%, p = 0.024). Further logistic regression analysis showed that concordant ictal EEG was an independent predictor for a favorable outcome (OR = 4.430, 95%CI 1.175-16.694, p = 0.028). Among MRI-positive patients, those with extra-temporal lesions and discordant ictal EEG results had a worse outcome compared to those without an ictal EEG result (44.7% vs. 68.8%, p = 0.005). Further logistic regression analysis showed that discordant ictal EEG was an independent predictor of worse outcome (OR = 0.387, 95%CI 0.186-0.807, p = 0.011) in these patients. Furthermore, our data indicated that the number of seizures was not associated with the concordance rates of the ictal EEG, nor the surgical outcomes.
CONCLUSIONS: The value of ictal scalp EEG for epilepsy surgery varies widely among patients. A concordant ictal EEG predicts a good surgical outcome in MRI-negative patients, whereas a discordant ictal EEG predicts a poor postoperative outcome in lesional extratemporal lobe epilepsy.

UNASSIGNED: Posterior cortex epilepsy (PCE) primarily comprises seizures originating from the occipital, parietal, and/or posterior edge of the temporal lobe. Electroclinical dissociation and subtle imaging representation render the diagnosis of PCE challenging. Improved methods for accurately identifying patients with PCE are necessary.
UNASSIGNED: To develop a novel voxel-based image postprocessing method for better visual identification of the neuroimaging abnormalities associated with PCE.
UNASSIGNED: Multicenter, retrospective study.
UNASSIGNED: Clinical and imaging features of 165 patients with PCE were retrospectively reviewed and collected from five epilepsy centers. A total of 37 patients (32.4% female, 20.2 ± 8.9 years old) with magnetic resonance imaging (MRI)-negative PCE were finally included for analysis. Image postprocessing features were calculated over a neighborhood for each voxel in the multimodality data. The postprocessed maps comprised structural deformation, hyperintense signal, and hypometabolism. Five raters from three different centers were blinded to the clinical diagnosis and determined the neuroimaging abnormalities in the postprocessed maps.
UNASSIGNED: The average accuracy of correct identification was 55.7% (range from 43.2 to 62.2%) and correct lateralization was 74.1% (range from 64.9 to 81.1%). The Cronbach\'s alpha was 0.766 for the correct identification and 0.683 for the correct lateralization with similar results of the interclass correlation coefficient, thus indicating reliable agreement between the raters.
UNASSIGNED: The image postprocessing method developed in this study can potentially improve the visual detection of MRI-negative PCE. The technique could lead to an increase in the number of patients with PCE who could benefit from the surgery.

Bottom-of-sulcus dysplasia (BOSD) is increasingly recognized as a cause of drug-resistant, surgically-remediable, focal epilepsy, often in seemingly MRI-negative patients. We describe the clinical manifestations, morphological features, localization patterns and genetics of BOSD, with the aims of improving management and understanding pathogenesis. We studied 85 patients with BOSD diagnosed between 2005-2022. Presenting seizure and EEG characteristics, clinical course, genetic findings and treatment response were obtained from medical records. MRI (3 T) and 18F-FDG-PET scans were reviewed systematically for BOSD morphology and metabolism. Histopathological analysis and tissue genetic testing were performed in 64 operated patients. BOSD locations were transposed to common imaging space to study anatomical location, functional network localization and relationship to normal MTOR gene expression. All patients presented with stereotyped focal seizures with rapidly escalating frequency, prompting hospitalization in 48%. Despite 42% patients having seizure remissions, usually with sodium channel blocking medications, most eventually became drug-resistant and underwent surgery (86% seizure-free). Prior developmental delay was uncommon but intellectual, language and executive dysfunction were present in 24%, 48% and 29% when assessed preoperatively, low intellect being associated with greater epilepsy duration. BOSDs were missed on initial MRI in 68%, being ultimately recognized following repeat MRI, 18F-FDG-PET or image postprocessing. MRI features were grey-white junction blurring (100%), cortical thickening (91%), transmantle band (62%), increased cortical T1 signal (46%) and increased subcortical FLAIR signal (26%). BOSD hypometabolism was present on 18F-FDG-PET in 99%. Additional areas of cortical malformation or grey matter heterotopia were present in eight patients. BOSDs predominated in frontal and pericentral cortex and related functional networks, mostly sparing temporal and occipital cortex, and limbic and visual networks. Genetic testing yielded pathogenic mTOR pathway variants in 63% patients, including somatic MTOR variants in 47% operated patients and germline DEPDC5 or NPRL3 variants in 73% patients with familial focal epilepsy. BOSDs tended to occur in regions where the healthy brain normally shows lower MTOR expression, suggesting these regions may be more vulnerable to upregulation of MTOR activity. Consistent with the existing literature, these results highlight (i) clinical features raising suspicion of BOSD; (ii) the role of somatic and germline mTOR pathway variants in patients with sporadic and familial focal epilepsy associated with BOSD; and (iii) the role of 18F-FDG-PET alongside high-field MRI in detecting subtle BOSD. The anatomical and functional distribution of BOSDs likely explain their seizure, EEG and cognitive manifestations and may relate to relative MTOR expression.

OBJECTIVE: The absence of MRI-lesion reduces considerably the probability of having an excellent outcome (International League Against Epilepsies [ILAE] class I-II) after epilepsy surgery. Surgical success in magnetic-resonance imaging (MRI)-negative cases relies therefore mainly on non-invasive techniques such as positron-emission tomography (PET), subtraction ictal/inter-ictal single-photon-emission-computed-tomography co-registered to MRI (SISCOM), electric source imaging (ESI) and morphometric MRI analysis (MAP). We were interested in identifying the optimal imaging technique or combination to achieve post-operative class I-II in patients with MRI-negative focal epilepsy.
METHODS: We identified 168 epileptic patients without MRI lesion. Thirty-three (19.6%) were diagnosed with unifocal epilepsy, underwent surgical resection and follow-up ⩾ 2 years. Sensitivity, specificity, predictive values, and diagnostic odds ratio (OR) were calculated for each technique individually and in combination (after co-registration).
RESULTS: 23/33 (70%) were free of disabling seizures (75.0% with temporal and 61.5% extratemporal lobe epilepsy). None of the individual modalities presented an OR > 1.5, except ESI if only patients with interictal epileptiform discharges (IEDs) were considered (OR 3.2). On a dual combination, SISCOM with ESI presented the highest outcome (OR = 6). MAP contributed to detecting indistinguishable focal cortical dysplasia in particular in extratemporal epilepsies with a sensitivity of 75%. Concordance of PET, ESI on interictal epileptic discharges, and SISCOM was associated with the highest chance for post-operative seizure control (OR = 11).
CONCLUSIONS: If MRI is negative, the chances to benefit from epilepsy surgery are almost as high as in lesional epilepsy, provided that multiple established non-invasive imaging tools are rigorously applied and co-registered together.

While magnetic resonance imaging (MRI) is the current standard imaging method for diagnosing and localizing corticotropinomas in Cushing disease, it can fail to detect adenomas in up to 40% of cases. Recently, positron emission tomography (PET) has shown promise as a diagnostic tool to detect pituitary adenomas in Cushing disease. We perform a scoping review to characterize the uses of PET in diagnosing Cushing disease, with a focus on describing the types of PET investigated and defining PET-positive disease. A scoping review was conducted following the PRISMA-ScR guidelines. Thirty-one studies fulfilled our inclusion criteria, consisting of 10 prospective studies, 8 retrospective studies, 11 case reports, and 2 illustrative cases with a total of 262 patients identified. The most commonly utilized PET modalities in prospective/retrospective studies were FDG PET (n = 5), MET PET (n = 5), 68 Ga-DOTATATE PET (n = 2), 13N-ammonia PET (n = 2), and 68 Ga-DOTA-CRH PET (n = 2). MRI positivity ranged from 13 to 100%, while PET positivity ranged from 36 to 100%. In MRI-negative disease, PET positivity ranged from 0 to 100%. Five studies reported the sensitivity and specificity of PET, which ranged from 36 to 100% and 50 to 100%, respectively. PET shows promise in detecting corticotropinomas in Cushing disease, including MRI-negative disease. MET PET has been highly investigated and has demonstrated excellent sensitivity and specificity. However, preliminary studies with FET PET and 68 Ga-DOTA-CRH PET show promise for achieving high sensitivity and specificity and warrant further investigation.

OBJECTIVE: This study aimed to differentiate temporal-plus epilepsy (TPE) from temporal lobe epilepsy (TLE) using extraction of radiomics features from three-dimensional magnetization-prepared rapid acquisition gradient echo (3D-MPRAGE) imaging data.
METHODS: Data from patients with TLE or TPE who underwent epilepsy surgery between January 2019 and January 2021 were retrospectively analyzed. Thirty-three regions of interest in the affected hemisphere of each patient were defined on 3D-MPRAGE images. A total of 3531 image features were extracted from each patient. Four feature selection methods and 10 machine learning algorithms were used to build 40 differentiation models. Model performance was evaluated using receiver operating characteristic analysis.
RESULTS: Eighty-two patients were included for analysis, 47 with TLE and 35 with TPE. The model combining logistic regression and the relief selection method had the best performance (area under the receiver operating characteristic curve, .779; accuracy, .875; sensitivity, .800; specificity, .929; positive predictive value, .889; negative predictive value, .867).
CONCLUSIONS: Radiomics analysis can differentiate TPE from TLE. The logistic regression classifier trained with radiomics features extracted from 3D-MPRAGE images had the highest accuracy and best performance.

To summarize the clinical features of epilepsy related to DEPDC5, NPRL2, and NPRL3 genes encoding the GATOR1 complex in children and to evaluate the factors affecting the prognosis of these epilepsies.
In this retrospective study, we reviewed the clinical and genetic characteristics of children with epilepsy related to GATOR1 variants who were admitted to the Peking University First Hospital between January 2016 and December 2021. Potential prognostic factors were assessed by comparing children with and without ongoing seizures.
Fifty probands, including 31 boys and 19 girls were recruited. The median age at onset of epilepsy was 4 months, and 64% of patients had early-onset epilepsy (≤1 year). The most frequent epileptic seizure type was focal seizure (86%). Among the 50 patients, only six were with de novo variants. According to the novel classification framework for GATOR1 variants, 36 patients were with pathogenic variants and 14 with likely pathogenic variants. DEPDC5 variants were found in 37 patients, NPRL3 in 9, and NPRL2 in 4. The phenotype was similar among the probands, with variants in DEPDC5, NRPL2, or NPRL3. 76% (38/50) of epilepsy related to GATOR1 variants was neuroimaging positive, including brain MRI positive in 31 patients, and MRI combined F-18-fluorodeoxyglucose positron emission tomography positive in the other seven patients. Twenty-seven patients underwent epilepsy surgery. In total, after initial antiseizure medications alone, 92% (46/50) of patients were drug-resistant epilepsies, only 8% (4/50) of the probands became seizure-free but seizure-free (≥6 m) occurred in 92.6% (25/27) of patients with drug-resistant epilepsy after epilepsy surgery at the last follow-up. Patients undergoing epilepsy surgery had better epilepsy prognosis.
Epilepsy related to GATOR1 variants had high possibility to be drug-resistant epilepsy and to have positive neuroimaging finding. Epilepsy surgery is the only favorable factor for better seizure prognosis in this kind epilepsy.

OBJECTIVE: MRI-negative focal epilepsy is one of the most challenging cases in surgical epilepsy treatment. Many epilepsy centers recommend intracranial electroencephalography (EEG) for MRI-negative cases, especially neocortical epilepsy. This retrospective study aimed to explore whether intracranial monitoring is mandatory in MRI-negative neocortical epilepsy surgery and the factors that significantly influence the decision on whether to perform intracranial recording.
METHODS: In this study, consecutive surgical patients with focal MRI-negative neocortical epilepsy were recruited. All patients underwent routine preoperative evaluation according to the dedicated protocol of the authors\' epilepsy center to determine the treatment strategy. Patients were divided into two groups according to the surgical strategy, i.e., a direct group and a stereo-EEG (SEEG)-guided group. History of epilepsy, seizure frequency, interictal and ictal EEG data, PET data, PET/MRI coregistration data, neuropathological findings, and surgical outcomes were compared between the two groups. Multivariate analysis was performed to identify factors influencing the decision to perform SEEG monitoring.
RESULTS: Sixty-four patients were included in this study, 19 and 45 of whom underwent direct and SEEG-guided cortical resection, respectively. At an average follow-up of 3.9 years postoperatively, 56 patients (87.5%) had Engel class I results without permanent neurological deficits. Surgical outcomes were not significantly different between the direct and SEEG-guided groups (94.7% vs 84.4%). PET hypometabolic abnormalities were detected in all patients. There were significant differences between the two groups in the extent of hypometabolism (focal vs nonfocal, p < 0.01) and pathological subtype (focal cortical dysplasia type II vs others, p = 0.03). Multivariate analysis revealed that the extent of hypometabolism (OR 0.01, 95% CI 0.00-0.15; p = 0.001) was the only independent factor affecting the treatment strategy.
CONCLUSIONS: Careful selection of patients with MRI-negative neocortical epilepsy may yield favorable outcomes after direct cortical resection without intracranial monitoring. PET/MRI coregistration plays an essential role in the preoperative evaluation and subsequent resection of these patients. Intracranial monitoring is not a mandatory requirement for surgery if the focal hypometabolic areas are consistent with the findings of semiology and scalp EEG.

OBJECTIVE: Several surgical strategies have been proposed to treat MRI-negative Cushing\'s Disease. These include tumor removal, if identified, and if a tumor is not identified, resection of varying degrees of the pituitary gland, often guided by inferior petrosal sinus sampling (IPSS). The relative risks and benefits of each strategy have never been compared.
METHODS: This systematic review of the literature included only studies on the results of surgery for MRI-negative patients with Cushing\'s Disease in which the surgical strategy was clearly described and associated remission and/or hypopituitarism rates detailed for each strategy.
RESULTS: We identified 12 studies that met inclusion criteria for remission rates and 5 studies for hypopituitarism rates. We divided cases into 6 resection strategies. Remission and hypopituitarism rates for each strategy were: (1) tumor identified, resect tumor only (68%, 0%); (2) resect tumor and surrounding capsule (85%, 0%); and if the tumor was not identified (3) resect inferior 1/3 of gland (78%, no data); (4) resect 30-50% of gland based on IPSS (68%, 13%); (5) resect > 50% but < 100% of gland (65%, 9%); (6) resect entire gland (66%, 67%). Strategy 3 only contained 9 patients.
CONCLUSIONS: Remission rates for MRI-negative Cushing\'s Disease support surgery as a reasonable approach. Results are best if a tumor is found. If a tumor is not identified, one can either remove one-third of the gland guided by IPSS lateralization, or remove both lateral portions along with the inferior portion leaving sufficient central gland to preserve function. Our recommendations are limited by the lack of rigorous and objective data.