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Background With regard to somatosensory delusion, neglect or deficits of body integrity a great number of overlapping pathophysiological concepts exist. Moreover, the range of assumed underlying psychiatric and neurologic syndromes only partially is thought to be related to even diverse neuroanatomical structures so far: Alien Hand Syndrome, Body Dysmorphic Disorder (BDD), Body Integrity Identity Disorder (BIID), Depersonalization, Somatoparaphrenia and Xenomelia. Specific deafferentiation within temporal regions, the insula or representational structures of the somatosensory cortex of the right parietal lobe is thought to be related only in some variants. We report a case of a 58-year old right-handed woman that experienced a progressive left-sided hemiparesis which initially could be related to a space occupying lesion and edema in the right central region of the brain. After anti-edematous therapy and consecutive surgical evacuation a cortical and subcortical defect in between the right postcentral gyrus junction to the precentral gyrus resulted into inanimate, not inherent sensations especially of the left forearm and knee without anosognosia after complete recovery of motor function and sensitivity. The neuropsychological assessment showed no impairments. Methods We demonstrate structural (conventional MRI) and functional imaging findings (diffusion tensor imaging; DTI, and, motor and somatosensory functional MRI) in relation to the subject”s somatosensory delusions. Results Structural MRI displayed a well-defined cortical and subcortical lesion in deep central sulcus surrounded by gliosis and hemosiderin deposits. DTI revealed a marked reduction of structural inter-connection between precentral and postcentral gyrus. In fMRI the motor paradigm series of dorsal flexion of the feet or clenching the fists showed no difference in activation of the correspondent precentral gyrus. The sensor paradigm series in contrast revealed a lower posterior activation of the right postcentral area during brushing the planta pedis and the left forearm. Discussion The hereby presented case possesses rare clinically segregated symptoms of somatoparaphrenia without anosognosia or hemiparesis in conjunction with a well-defined postcentral lesion. The symptoms may be related to a corresponding reduced postcentral activation and restricted functional interconnection between motor and sensory cortex. From our point of view these results document the essential requirement of postcentral gyrus activation and regional conduction for regular experience of sensorial authenticity. [ABSTRACT FROM AUTHOR]

Objectives: Symmetry is essential for computer-aided surgical (CAS) procedures in oral and maxillofacial surgery (OMFS). A critical step for successful CAS is mirroring the unaffected side to create a template for the virtual reconstruction of the injured anatomical structure. The aim was to identify specific anatomical landmarks of the midfacial skeleton, to evaluate the symmetry in a group of the real-world Central European population, and to use these landmarks to assess midfacial symmetry in CT scans., Material and Methods: The retrospective cross-sectional study defined landmarks of the midface's bony contour using viscerocranial CT data. The distances of the skeletal landmarks (e.g., the frontozygomatic suture and temporozygomatic suture) of the left and right sides from the midline were measured and statistically compared. Midfacial symmetry for reference points was defined as a difference within 0 mm and their mean difference plus one standard deviation., Results: We examined a total of 101 CT scans. 75% of our population shows symmetrical proportions of the midface. The means of the differences for the left and right sides ranged from 0.8 to 1.3 mm, averaging 1.1 ± 0.2 mm for all skeletal landmarks. The standard deviations ranged from 0.6 to 1.4 mm, with a computed mean of 0.9 ± 0.3 mm., Conclusion: We established a methodology to assess the symmetry of the bony midface. If the determined differences were equal to or lower than 2.5 mm in the mentioned midfacial skeletal landmarks, then the symmetry of the bony midface was considered present, and symmetry-based methods for CAS procedures are applicable., Clinical Relevance: Many CAS procedures require facial symmetry. We provide an easy-to-apply method to probe for symmetry of the midface. The method may be used for population-based research, to check for proper reduction of fractures after reposition or to screen for symmetry prior to CAS planning., (© 2023. The Author(s).)

Purpose:  We sought to determine the diagnostic agreement between the revised ultrasonography approach by the German Society of Ultrasound in Medicine (DEGUM) and the established Society of Radiologists in Ultrasound (SRU) consensus criteria for the grading of carotid artery disease., Materials and Methods:  Post-hoc analysis of a prospective multicenter study, in which patients underwent ultrasonography and digital subtraction angiography (DSA) of carotid arteries for validation of the DEGUM approach. According to DEGUM and SRU ultrasonography criteria, carotid arteries were independently categorized into clinically relevant NASCET strata (normal, mild [1-49 %], moderate [50-69 %], severe [70-99 %], occlusion). On DSA, carotid artery findings according to NASCET were considered the reference standard., Results:  We analyzed 158 ultrasonography and DSA carotid artery pairs. There was substantial agreement between both ultrasonography approaches for severe (κw 0.76, CI95 %: 0.66-0.86), but only fair agreement for moderate (κw 0.38, CI95 %: 0.19-0.58) disease categories. Compared with DSA, both ultrasonography approaches were of equal sensitivity (79.7 % versus 79.7 %; p = 1.0) regarding the identification of severe stenosis, yet the DEGUM approach was more specific than the SRU approach (70.2 % versus 56.4 %, p = 0.0002). There was equality of accuracy parameters (p > 0.05) among both ultrasonography approaches for the other ranges of carotid artery disease., Conclusion:  While the sensitivity was equivalent, false-positive identification of severe carotid artery stenosis appears to be more frequent when using the SRU ultrasonography approach than the revised multiparametric DEGUM approach., Competing Interests: The authors declare that they have no conflict of interest., (Thieme. All rights reserved.)

Quantitative spinal cord (SC) magnetic resonance imaging (MRI) presents many challenges, including a lack of standardized imaging protocols. Here we present a prospectively harmonized quantitative MRI protocol, which we refer to as the spine generic protocol, for users of 3T MRI systems from the three main manufacturers: GE, Philips and Siemens. The protocol provides guidance for assessing SC macrostructural and microstructural integrity: T1-weighted and T2-weighted imaging for SC cross-sectional area computation, multi-echo gradient echo for gray matter cross-sectional area, and magnetization transfer and diffusion weighted imaging for assessing white matter microstructure. In a companion paper from the same authors, the spine generic protocol was used to acquire data across 42 centers in 260 healthy subjects. The key details of the spine generic protocol are also available in an open-access document that can be found at https://github.com/spine-generic/protocols . The protocol will serve as a starting point for researchers and clinicians implementing new SC imaging initiatives so that, in the future, inclusion of the SC in neuroimaging protocols will be more common. The protocol could be implemented by any trained MR technician or by a researcher/clinician familiar with MRI acquisition., (© 2021. The Author(s), under exclusive licence to Springer Nature Limited.)

The insular cortex plays a key role in the integration of multimodal information and in interoceptive and exteroceptive processing. For instance, neurons in the central dorsal insula that are active during interoceptive tasks, also show an adaptation to gustatory stimulation. We tested the link between interoception and exteroception for the olfactory system (i.e., the second domain of chemosensation). In a sample of 31 participants, olfactory function was assessed in a two dimensional approach while the Heartbeat Perception Task served as a measurement for cardiac interoceptive accuracy. Subsequent fMRI sessions were performed on a 3-Tesla MR scanner containing 12-15 olfactory stimulation trials with a mildly pleasant food-related odor (coffee). Persons scoring high in the cardiac interoceptive accuracy task presented stronger smelling abilities as well as enhanced BOLD responses following olfactory stimulation. The olfactory stimulation triggered enhanced insular activation patterns in the central dorsal insular cortex. Consistent with prior findings on the coherence of gustatory and interoceptive processing in the central dorsal insula, these results base the insula as a common region for the integration of interoception and exteroception. We propose an explanatory model of how exteroception triggers the integration of intero- and exteroceptive sensations in the central dorsal insular cortex., (© 2020 The Authors. Human Brain Mapping published by Wiley Periodicals, Inc.)

Purpose:  The German Society of Ultrasound in Medicine (DEGUM) recently revised its multiparametric criteria for duplex ultrasonography (DUS) grading of internal carotid artery (ICA) disease. We determined the diagnostic accuracy of the revised DEGUM criteria for ultrasonography grading of ICA disease in a prospective multicenter study., Materials and Methods:  We evaluated consecutive patients who underwent digital subtraction angiography of the extracranial carotid arteries at four tertiary care hospitals. Blinded investigators graded ICA disease according to DEGUM-recommended ultrasonography criteria and calculated NASCET-type percent stenosis from angiography images. Endpoints included overall classification accuracy, prediction of clinically relevant disease categories and between-test agreement in the continuous range of percent stenosis., Results:  A total of 121 patients (median age: 69 [IQR, 16] years; 74 % men; median time between DUS and angiography: 1 day [IQR, 2]) provided 163 DUS-angiography carotid artery pairs. The classification accuracy of the DEGUM criteria to predict stenosis within 10 % increments as compared to angiography was 34.9 % (95 % CI, 28.0 - 42.6). The sensitivity of DUS for the detection of moderate (50 - 69 %) and severe (70 - 99 %) stenosis was 35 % and 81 %, with an overall accuracy of 73 % and 74 %, respectively. The specificity was 89 % and 69 %, respectively. Considering the continuous spectrum of the disease (0 - 100 %), the Bland-Altman interval limit of agreement was 51 %., Conclusion:  At laboratories experienced with ultrasound grading of the extracranial ICA, the revised DEGUM multiparametric ultrasonography criteria do not eliminate the need for a confirmatory test for the identification of clinically relevant grades of the disease., Competing Interests: Disclosure The authors report no conflicts of interest in this work., (© Georg Thieme Verlag KG Stuttgart · New York.)

Background: Removal of the olfactory bulb (OB) leads to depression like behavior in rodents. A link between depression and olfactory function is also established in humans. We hypothesized that the human OB volume relates to depressive state and tested whether such a potential coherence is moderated by structural alterations in other brain regions., Methods: Eighty-three participants (32 patients with major depression and 51 matched healthy controls) underwent structural MR scanning. Individual OB volumes were compared between patients and controls and the impact of depression and comorbidity was analyzed with multiple regression analysis. Whole-brain voxel-based morphometry revealed structures co-varying with both depressive state and OB volume., Results: The OB volume of patients was significantly reduced and this reduction averaged out at 17% compared to the controls. The OB volume was correlated to the volume of the insula, superior temporal cortex, and amygdala. The independent variables of depression (β = -.37), age (β = -.25), and gender (β = -.40) explained the individual OB volume variation (R 2  = .37). The correlation between OB volume and depression was moderated by volumetric reductions in a cluster including the insula and superior temporal gyrus (STG)., Conclusions: The OB volume relates to depression in humans and to the volume of structures which are critical for salience detection. We assume that a reduced OB volume causes diminished neural olfactory input which facilitates volume reduction in the insula and STG. The OB volume may hence constitute a factor of vulnerability to depression. Olfactory-based deep brain stimulation is discussed as a future therapeutic approach., (© 2018 Wiley Periodicals, Inc.)

Purpose: Clinically successful endovascular therapy (EVT) in ischemic stroke requires reliable noninvasive pretherapeutic selection criteria. We investigated the association of imaging parameters including CT angiographic collaterals and degree of reperfusion with clinical outcome after EVT., Methods: In our database, we identified 93 patients with large vessel occlusion in the anterior circulation treated with EVT. Besides clinical data, we assessed the baseline Alberta Stroke Program Early CT score (ASPECTS) on noncontrast CT (NCCT) and CT angiography (CTA) source images, collaterals (CT-CS) and clot burden score (CBS) on CTA and the degree of reperfusion after EVT on angiography. Three readers, blinded to clinical information, evaluated the images in consensus. Data-driven multivariable ordinal regression analysis identified predictors of good outcome after 90 days as measured with the modified Rankin Scale., Results: Successful angiographic reperfusion (OR 26.50; 95%-CI 9.33-83.61) and good collaterals (OR 9.69; 95%-CI 2.28-59.27) were independent predictors of favorable outcome along with female sex (OR 0.35; 95%-CI 0.14-0.85), younger age (OR 0.88; 95%-CI 0.83-0.92) and higher NCCT ASPECTS (OR 2.54; 95%-CI 1.01-6.63). Outcome was best in patients with good collaterals and successful reperfusion, but there was no statistical interaction between collaterals and reperfusion., Conclusions: CTA-collateral status was the strongest pretherapeutic predictor of favorable outcome in ischemic stroke patients treated with EVT. CTA-collaterals are thus well suited for patient selection in EVT. However, the independent effect of reperfusion on outcome tended to be stronger than that of CTA-collaterals.

An overwhelming benefit from endovascular treatment of ischaemic stroke could be shown in recent clinical trials, making it the new evidence-based standard of care for ischaemic stroke due to large vessel occlusion. To provide all eligible stroke patients with this therapy at any time, stroke networks and hospitals should streamline their workflow to rapidly image, select, and treat stroke patients. Interdisciplinary cooperation is vital for effective emergency endovascular stroke treatment, which is one of the most complex multidisciplinary functions a hospital can undertake.

Background: Cortical lesions in status epilepticus have been reported but the underlying mechanisms are poorly elucidated., Case Summary: We report on afemale patient (75 years) with a history of alcohol abuse who presented with complex partial status epilepticus and lateralized epileptiform discharges in the left frontal and temporal regions in EEG. While cranial magnetic resonance imaging (MRI) showed left hippocampal T2-hyperintensity and diffusion restriction, cerebrospinal fluid was normal and revealed no limbic encephalitis-related antibodies. Following treatment with levitiracetam, seizures ceased and the patient was dismissed. Nine months later, she was readmitted with generalized status epilepticus. Cranial MI now showed hippocampal diffusion restriction and T2 hyperintensity, but in the right hemisphere, as well as atrophy and partial gliotic transformation of the initially affected left hippocampus., Discussion: Although hippocampal damage due to antibody-negative limbic encephalitis cannot be ruled out, our observation of subsequent bilateral hippocampal diffusion restriction with gliotic transformation may demonstrate permanent seizure-induced structural brain damage and underlines the importance of further research to elucidate the effects of prolonged epileptic discharges on cerebral structural integrity.

Purpose: This study investigates the performance of a 3 D Ultrasound (US) system in imaging elbow and wrist nerves., Materials and Methods: Twenty healthy volunteers with asymptomatic median, ulnar and radial nerves were prospectively investigated. Bilateral 3DUS scans of the elbows and wrists were acquired by using a commercially available US scanner (18 MHz, AplioXG, Toshiba) and stored as a 3 D volume by a dedicated software (CURE, Robarts Research Institute). Retrospectively, qualitative (image quality, atypical nerve location, findings potentially associated with compression neuropathy) and quantitative (cross-sectional area measurements) evaluations were performed., Results: In all 200 nerves 3DUS was feasible (100%). Image quality was insufficient in 13.5% (25 ulnar nerve elbow, 2 radial nerve) and sonomorphology was not assessable in those nerves. Measurement of cross sectional areas was feasible in all nerves (100%). Median cross-sectional area (range) were: median nerve elbow 7 mm2 (6-9), radial nerve 3 mm2 (1-4), ulnar nerve elbow 8 mm2 (5-11), median nerve wrist 8 mm2 (5-10), and ulnar nerve wrist 4 mm2 (2-6). No significant changes in nerve cross-sectional area along each nerve was found. Ulnar nerve subluxation was found in 2 nerves (6.7%). No anconeus epitrochlearis muscle or osteophytes were found., Conclusion: 3DUS is a feasible method for assessing nerves of the upper extremity and has been shown to provide a good overview of the median, ulnar and radial nerve at the elbow and wrist, but is limited for evaluation of the ulnar nerve in the cubital tunnel. This technique enables reliable measurements at different locations along the nerve., (© Georg Thieme Verlag KG Stuttgart · New York.)

Wilson's disease is a rare autosomal recessive disorder characterized by the accumulation of copper, mainly in the liver and the brain. As copper accumulation in the brain leads to disturbances in basal ganglia function, neurological-type patients typically present with hypo- and hyperkinetic extrapyramidal symptoms, with Parkinsonism being very common. Although there are numerous reports on olfactory deficits in primary neurodegenerative disorders, olfactory function has not been investigated in metabolic disorders presenting with extrapyramidal features. Twenty-four patients with Wilson's disease participated in the investigation. All patients were treated pharmacologically. They comprised patients with liver disease alone (including mild enzyme elevation in asymptomatic individuals; n = 11) and/or neurological symptoms (n = 13) at the time of testing. Twenty-one patients underwent both [18F]fluoro-2-deoxy-D-glucose positron emission tomography ([18F]FDG-PET) and magnetic resonance imaging (MRI). The severity of extrapyramidal symptoms was judged using a clinical score system ranging from 0 (no symptoms) to 3 (severe symptoms). In all patients, psychophysical testing was performed using the Sniffin' Sticks, which involved tests for odor threshold, discrimination, and identification. Results from the present study revealed that Wilson's disease patients with neurological symptoms show a significant olfactory dysfunction compared to hepatic-type patients. Individuals who are more severely neurologically affected also present with a more pronounced olfactory deficit. Of interest, there was no significant effect of long-term treatment with penicillamine on olfactory function. Olfactory function did not correlate significantly with the presence of MRI visible lesions in the basal ganglia or with any regional glucose metabolism as measured by [18]F-FDG-PET. In conclusion, these findings indicate that the underlying pathological alterations with degeneration in the basal ganglia and neuronal loss in association with a marked increase of the copper content in this brain region play a role in the olfactory deficit.

Acquisition, analysis, and visualization of diffusion tensor magnetic resonance imaging (DT-MRI) is still an evolving technology. This article reviews the fundamentals of the data acquisition process and the pipeline leading to visual results that are interpretable by physicians in their clinical practice. The limitations of common approaches for visualizing the retrieved data are discussed and a new statistical method is presented to assess the reliability of the acquired tensor field. A novel visualization method is proposed which is discussed in light of neurophysiological considerations of the perception of colored patterns. It is argued that this method is more accurate for medical data while providing a nearly optimal visual stimulus. The method is evaluated on a patient study with a brain tumor.

Purpose: Microangiopathic lesions of the brain tissue correlate with the clinical diagnosis of vascular subcortical dementia. The "experience-based" evaluation is insufficient. Rating scales may contribute to reproducible quantification., Materials and Methods: In MRI studies of 10 patients, 9 neuroradiologists quantified vascular white matter lesions (WMLs) at two different points in time for 12 anatomically defined regions with respect to number, size and localization (score). For 9 observers and 10 studies, 90 intra-observer differences were obtained for each of the 12 WML scores. To calculate the inter-observer reliability, rating pairs were formed. Furthermore, 360 differences were computed for each score and rating for 12 anatomically defined WML scores, and the intraclass correlation (ICC) was calculated as a measure of agreement (reliability)., Results: As to the intra-observer reliability, the median of the differences was 1.5 for the entire brain as opposed to 0 for defined brain regions. The corresponding values for the inter-observer reliability were 3 and 1, respectively. The mean intra-class correlation coefficient for the 10 studies was 0.88, whereas the mean interclass correlation concerning the inter-observer reliability was 0.70, with the first and second rating being averaged. The rating of each study took about 6 minutes., Conclusion: The rating scale with high intra- and inter-observer reliability can dependably quantify WMLs and correlates with the clinical diagnosis of vascular dementia. Using a reliable rating scale, the diagnostic distinction of age-associated physiological vs. pathological size of the WML can make a contribution to the reproducible quantifiable diagnostic evaluation of vascular brain tissue lesions within the framework of dementia diagnostics.

In spite of marked disability, patients with primary progressive multiple sclerosis (PPMS) display smaller lesion volumes on conventional magnetic resonance imaging (MRI) compared with other forms of multiple sclerosis (MS). Hence, damage to the normal-appearing brain tissue (NABT) may play an important role in explaining the pathogenesis of disability in PPMS. Diffusion-weighted MRI (DW-MRI) probes water diffusion in vivo that can be altered by pathologic changes. Using DW-MRI we investigated diffusion in the NABT of 15 patients with PPMS over one year. The average apparent diffusion coefficient (ADCav) was measured in 10 regions of interest located in the normal-appearing thalamus and the normal-appearing white matter (NAWM). Six healthy subjects served as a reference. In contrast to healthy subjects, patients with PPMS showed an increment within 12 months of the ADCav in NAWM which was associated with an increase of the T2- and T1-lesion volumes. The ADCav in frontal NAWM was associated with disability as measured by the MS Functional Composite Measure. Serial DW-MRI depicts progressive changes in the NAWM of patients with PPMS. Our preliminary findings suggest that the processes causing structural damage in NAWM and lesions in patients with PPMS are partially linked and that changes of water diffusion in NAWM depicted by DW-MRI are clinically relevant.