From a dysembryoplastic neuroepithelial tumor to a glioblastoma multiforme: Pitfalls of initial diagnosis on biopsy material, a case report.

BACKGROUND: Ganglioglioma (GG) and dysembryoplastic neuroepithelial tumor (DNET) belong to the group of low-grade epilepsy-associated tumors (LEAT) and are the most prevalent tumor types found in patients undergoing epilepsy surgery. Histopathological differentiation between GG and DNET can be difficult on biopsies due to limited tumor tissue. CASE DESCRIPTION: Here, we present a rare case where a low-grade tumor was initially classified as DNET, based on biopsy findings and unfortunately dedifferentiated within 10 years into a glioblastoma multiforme. After gross total resection, the initial tumor was reclassified as GG. CONCLUSION: This case illustrates the diagnostic challenges of LEAT, especially on biopsy material. Therefore, we advocate to counsel for complete resection and histopathological diagnosis utilizing tumor markers to confirm the nature of the tumor and to advice type of follow-up and eventual concurrent treatment.

Neurosarcoidosis with hydrocephalus as a first presenting sign: a unique case report.

There is a possible relationship with cerebral ischemic events and neurosarcoidosis. It should be considered in the differential diagnosis in a case of unexplained hydrocephalus, vascular white matter lesions and vasculitis related findings.

Dual-Energy CT Angiography Improves Accuracy of Spot Sign for Predicting Hematoma Expansion in Intracerebral Hemorrhage.

BACKGROUND AND PURPOSE: Spot sign (SS) on computed tomography angiography (CTA) is associated with hematoma expansion (HE) and poor outcome after intracerebral hemorrhage (ICH). However, its predictive performance varies across studies, possibly because differentiating hyperdense hemorrhage from contrast media is difficult. We investigated whether dual-energy-CTA (DE-CTA), which can separate hemorrhage from iodinated contrast, improves the diagnostic accuracy of SS for predicting HE. METHODS: Primary ICH patients undergoing DE-CTA (both arterial as well as delayed venous phase) and follow-up computed tomography were prospectively included between 2014 and 2019. SS was assessed on both arterial and delayed phase images of the different DE-CTA datasets, i.e., conventional-like mixed images, iodine images, and fusion images. Diagnostic accuracy of SS for prediction of HE was determined on all datasets. The association between SS and HE, and between SS and poor outcome (modified Rankin Scale at 3 months ≥3) was assessed with multivariable logistic regression, using the dataset with highest diagnostic accuracy. RESULTS: Of 139 included patients, 47 showed HE (33.8%). Sensitivity of SS for HE was 32% (accuracy 0.72) on conventional-like mixed arterial images which increased to 76% (accuracy 0.80) on delayed fusion images. Presence of SS on delayed fusion images was independently associated with HE (odds ratio [OR], 17.5; 95% confidence interval [CI], 6.14 to 49.82) and poor outcome (OR, 3.84; 95% CI, 1.16 to 12.73). CONCLUSIONS: Presence of SS on DE-CTA, in particular on delayed phase fusion images, demonstrates higher diagnostic performance in predicting HE compared to conventional-like mixed imaging, and it is associated with poor outcome.

Detection of Bone Marrow Edema in the Head and Neck With Dual-Energy CT: Ready for Clinical Use?

OBJECTIVE. The aim of this study is to evaluate the ability of dual-energy CT (DECT) to identify bone marrow edema (BME) in the head and neck region in comparison with MRI as the standard of reference. MATERIALS AND METHODS. A total of 33 patients who underwent imaging between February 2016 and February 2018 were included in this retrospective study. All patients underwent both DECT and MRI for head and neck abnormalities. Two radiologists independently visually assessed virtual noncalcium (VNCa) reconstructions with color-coded maps for the presence of BME. STIR or T2-weighted MRI reconstructions with fat suppression were used as the standard of reference for BME. Subjective quality assessment and severity of metal artifacts were scored on both imaging modalities. RESULTS. BME was detected in 18 patients on DECT compared with 20 patients on MRI. Most BME seen on DECT was located in the mandible. VNCa DECT images had a sensitivity, specificity, positive predictive value, and negative predictive value for BME of 85%, 92%, 94%, and 80% respectively, using MRI as the reference. The quality of the images was rated as excellent to moderate in 94% of the patients for VNCa DECT compared with 82% of the patients for MRI, but this difference was not statistically significant. Significantly more metal artifacts were scored on the mixed DECT images than on the MR images, but these artifacts did not interfere with diagnosis. CONCLUSION. BME detection in the head and neck region seems possible with VNCa DECT images and has the potential to provide an alternative for MRI in clinical practice.

Delphi definition of the EADC-ADNI Harmonized Protocol for hippocampal segmentation on magnetic resonance.

BACKGROUND: This study aimed to have international experts converge on a harmonized definition of whole hippocampus boundaries and segmentation procedures, to define standard operating procedures for magnetic resonance (MR)-based manual hippocampal segmentation. METHODS: The panel received a questionnaire regarding whole hippocampus boundaries and segmentation procedures. Quantitative information was supplied to allow evidence-based answers. A recursive and anonymous Delphi procedure was used to achieve convergence. Significance of agreement among panelists was assessed by exact probability on Fisher's and binomial tests. RESULTS: Agreement was significant on the inclusion of alveus/fimbria (P = .021), whole hippocampal tail (P = .013), medial border of the body according to visible morphology (P = .0006), and on this combined set of features (P = .001). This definition captures 100% of hippocampal tissue, 100% of Alzheimer's disease-related atrophy, and demonstrated good reliability on preliminary intrarater (0.98) and inter-rater (0.94) estimates. DISCUSSION: Consensus was achieved among international experts with respect to hippocampal segmentation using MR resulting in a harmonized segmentation protocol.

The EADC-ADNI Harmonized Protocol for manual hippocampal segmentation on magnetic resonance: evidence of validity.

BACKGROUND: An international Delphi panel has defined a harmonized protocol (HarP) for the manual segmentation of the hippocampus on MR. The aim of this study is to study the concurrent validity of the HarP toward local protocols, and its major sources of variance. METHODS: Fourteen tracers segmented 10 Alzheimer's Disease Neuroimaging Initiative (ADNI) cases scanned at 1.5 T and 3T following local protocols, qualified for segmentation based on the HarP through a standard web-platform and resegmented following the HarP. The five most accurate tracers followed the HarP to segment 15 ADNI cases acquired at three time points on both 1.5 T and 3T. RESULTS: The agreement among tracers was relatively low with the local protocols (absolute left/right ICC 0.44/0.43) and much higher with the HarP (absolute left/right ICC 0.88/0.89). On the larger set of 15 cases, the HarP agreement within (left/right ICC range: 0.94/0.95 to 0.99/0.99) and among tracers (left/right ICC range: 0.89/0.90) was very high. The volume variance due to different tracers was 0.9% of the total, comparing favorably to variance due to scanner manufacturer (1.2), atrophy rates (3.5), hemispheric asymmetry (3.7), field strength (4.4), and significantly smaller than the variance due to atrophy (33.5%, P < .001), and physiological variability (49.2%, P < .001). CONCLUSIONS: The HarP has high measurement stability compared with local segmentation protocols, and good reproducibility within and among human tracers. Hippocampi segmented with the HarP can be used as a reference for the qualification of human tracers and automated segmentation algorithms.

Diagnostic imaging of patients in a memory clinic: comparison of MR imaging and 64-detector row CT.

PURPOSE: To investigate the assessment of global cortical atrophy (GCA), medial temporal lobe atrophy (MTA), and white matter changes (WMCs) in patients screened at a memory clinic with a 64-detector row computed tomography (CT) brain protocol, in comparison with the reference standard, magnetic resonance (MR) imaging. MATERIALS AND METHODS: The study protocol was approved by the local institutional review board. Written informed consent was obtained from all participants. Thirty patients (21 men, nine women; median age, 62 years) who presented to a memory clinic underwent 64-detector row CT and multisequence MR imaging of the brain on the same day. Three readers blinded to the clinical diagnosis assessed the resultant images. Images were presented in random order and scored for GCA, MTA, and WMC with published visual rating scales. Intermodality agreement between CT and MR imaging (intrareader agreement across both modalities), expressed by weighted kappa analysis, and interobserver agreement within each modality between readers (Kendall W test) were assessed. RESULTS: Overall, excellent intraobserver agreement between CT and MR imaging was observed for GCA (mean kappa, 0.83) and MTA (mean kappa, 0.88 and 0.86 on the left and right sides of the brain, respectively). There was substantial overall agreement concerning WMC (mean kappa, 0.79). For all three tested scales, interobserver variability was low and comparable for CT and MR imaging. CONCLUSION: Use of 64-detector row brain CT yields reliable information that is comparable with that obtained with MR imaging. Thus, multidetector row CT is a suitable diagnostic imaging tool in a memory clinic setting.

Progression of mild cognitive impairment to dementia: contribution of cerebrovascular disease compared with medial temporal lobe atrophy.

BACKGROUND AND PURPOSE: We sought to determine the predictive value of magnetic resonance imaging measures of vascular disease (white matter hyperintensities [WMHs], lacunes, microbleeds, and infarcts) compared with atrophy on the progression of mild cognitive impairment to dementia. METHODS: We included 152 consecutive patients with mild cognitive impairment. Baseline magnetic resonance imaging was used to determine the presence of medial temporal lobe atrophy and vascular disease (presence of lacunes, microbleeds, and infarcts was determined, and WMHs were rated on a semiquantitative scale). Patients were followed up for 2+/-1 years. RESULTS: Seventy-two (47%) patients progressed to dementia during follow-up. Of these, 56 (37%) patients were diagnosed with Alzheimer's disease, and 16 (10%) patients were diagnosed with a non-Alzheimer dementia (including vascular dementia, frontotemporal lobar degeneration, and Parkinson dementia). Converters were older and had a lower Mini-Mental State Examination score at baseline. On baseline magnetic resonance imaging, patients who progressed to a non-Alzheimer dementia showed more severe WMHs and had a higher prevalence of lacunes in the basal ganglia and microbleeds compared with nonconverters. Cox proportional-hazard models showed that, adjusted for age and sex, baseline medial temporal lobe atrophy (hazard ratio=2.9; 95% CI, 1.7 to 5.3), but not vascular disease, was associated with progression to Alzheimer's disease. By contrast, deep WMHs (hazard ratio=5.7; 95% CI, 1.2 to 26.7) and periventricular hyperintensities (hazard ratio=6.5; 95% CI, 1.4 to 29.8) predicted progression to non-Alzheimer dementia. Furthermore, microbleeds (hazard ratio=2.6; 95% CI, 0.9 to 7.5) yielded a >2-fold increased, though nonsignificant, risk of non-Alzheimer dementia. CONCLUSIONS: Medial temporal lobe atrophy and markers of cerebrovascular disease predict the development of different types of dementia in mild cognitive impairment patients.

MRI biomarkers of vascular damage and atrophy predicting mortality in a memory clinic population.

BACKGROUND AND PURPOSE: MRI biomarkers play an important role in the diagnostic work-up of dementia, but their prognostic value is less well-understood. We investigated if simple MRI rating scales predict mortality in a memory clinic population. METHODS: We included 1138 consecutive patients attending our memory clinic. Diagnostic categories were: subjective complaints (n=220), mild cognitive impairment (n=160), Alzheimer disease (n=357), vascular dementia (n=46), other dementia (n=136), and other diagnosis (n=219). Baseline MRIs were assessed using visual rating scales for medial temporal lobe atrophy (range, 0-4), global cortical atrophy (range, 0-3), and white matter hyperintensities (range, 0-3). Number of microbleeds and presence of infarcts were recorded. Cox-regression models were used to calculate the risk of mortality. RESULTS: Mean follow-up duration was 2.6 (+/-1.9) years. In unadjusted models, all MRI markers except infarcts predicted mortality. After adjustment for age, sex, and diagnosis, white matter hyperintensities, and microbleeds predicted mortality (white matter hyperintensities: hazard ratio [HR], 1.2; 95% CI, 1.0-1.4; microbleeds: HR, 1.02 95% CI, 1.00-1.03; categorized: HR, 1.5; 95% CI, 1.1-2.0). The predictive effect of global cortical atrophy was restricted to younger subjects (HR, 1.7; 95% CI, 1.2-2.6). An interaction between microbleeds and global cortical atrophy indicated that mortality was especially high in patients with both microbleeds and global cortical atrophy. CONCLUSIONS: Simple MRI biomarkers, in addition to their diagnostic use, have a prognostic value with respect to mortality in a memory clinic population. Microbleeds were the strongest predictor of mortality.

The pilot European Alzheimer's Disease Neuroimaging Initiative of the European Alzheimer's Disease Consortium.

BACKGROUND: In North America, the Alzheimer's Disease Neuroimaging Initiative (ADNI) has established a platform to track the brain changes of Alzheimer's disease. A pilot study has been carried out in Europe to test the feasibility of the adoption of the ADNI platform (pilot E-ADNI). METHODS: Seven academic sites of the European Alzheimer's Disease Consortium (EADC) enrolled 19 patients with mild cognitive impairment (MCI), 22 with AD, and 18 older healthy persons by using the ADNI clinical and neuropsychological battery. ADNI compliant magnetic resonance imaging (MRI) scans, cerebrospinal fluid, and blood samples were shipped to central repositories. Medial temporal atrophy (MTA) and white matter hyperintensities (WMH) were assessed by a single rater by using visual rating scales. RESULTS: Recruitment rate was 3.5 subjects per month per site. The cognitive, behavioral, and neuropsychological features of the European subjects were very similar to their U.S. counterparts. Three-dimensional T1-weighted MRI sequences were successfully performed on all subjects, and cerebrospinal fluid samples were obtained from 77%, 68%, and 83% of AD patients, MCI patients, and controls, respectively. Mean MTA score showed a significant increase from controls (left, right: 0.4, 0.3) to MCI patients (0.9, 0.8) to AD patients (2.3, 2.0), whereas mean WMH score did not differ among the three diagnostic groups (between 0.7 and 0.9). The distribution of both MRI markers was comparable to matched US-ADNI subjects. CONCLUSIONS: Academic EADC centers can adopt the ADNI platform to enroll MCI and AD patients and older controls with global cognitive and structural imaging features remarkably similar to those of the US-ADNI.