Structured Reporting in Multiple Sclerosis - Consensus-Based Reporting Templates for Magnetic Resonance Imaging of the Brain and Spinal Cord. / Strukturierte Befundung bei Multipler Sklerose ­ Konsensbasierte Befundvorlagen für die magnetresonanztomografische Untersuchung des Gehirns und des Rückenmarks.

As a result of technical developments and greater availability of imaging equipment, the number of neuroradiological examinations is steadily increasing [1]. Due to improved image quality and sensitivity, more details can be detected making reporting more complex and time-intensive. At the same time, reliable algorithms increasingly allow quantitative image analysis that should be integrated in reports in a standardized manner. Moreover, increasing digitalization is resulting in a decrease in the personal exchange between neuroradiologists and referring disciplines, thereby making communication more difficult. The introduction of structured reporting tailored to the specific disease and medical issue [2, 3] and corresponding to at least the second reporting level as defined by the German Radiological Society (https://www.befundung.drg.de/de-DE/2908/strukturierte-befundung/) is therefore desirable to ensure that the quality standards of neuroradiological reports continue to be met.The advantages of structured reporting include a reduced workload for neuroradiologists and an information gain for referring physicians. A complete and standardized list with relevant details for image reporting is provided to neuroradiologists in accordance with the current state of knowledge, thereby ensuring that important points are not forgotten [4]. A time savings and increase in efficiency during reporting were also seen [5]. Further advantages include report clarity and consistency and better comparability in follow-up examinations regardless of the neuroradiologist's particular reporting style. This results in better communication with the referring disciplines and makes clinical decision significantly easier [6, 7]. Although the advantages are significant, any potential disadvantages like the reduction of autonomy in reporting and inadequate coverage of all relevant details and any incidental findings not associated with the main pathology in complex cases or in rare diseases should be taken into consideration [4]. Therefore, studies examining the advantages of structured reporting, promoting the introduction of this system in the clinical routine, and increasing the acceptance among neuroradiologists are still needed.Numerous specific templates for structured reporting, e. g., regarding diseases in cardiology and oncology, are already available on the website www.befundung.drg.de . Multiple sclerosis (MS) is an idiopathic chronic inflammatory and neurodegenerative disease of the central nervous system and is the most common non-trauma-based inflammatory neurological disease in young adults. Therefore, it has significant individual and socioeconomic relevance [8]. Magnetic resonance imaging (MRI) plays an important role in the diagnosis, prognosis evaluation, and follow-up of this disease. MRI is established as the central diagnostic method in the diagnostic criteria. Therefore, specific changes are seen on MRI in almost all patients with a verified MS diagnosis [9]. Reporting of MRI datasets regarding the brain and spinal cord of patients with MS includes examination of the images with respect to the relevant medical issue in order to determine whether the McDonald criteria, which were revised in 2017 [10] and define dissemination in time and space clinically as well as with respect to MRI based on the recommendations of the MAGNIMS groups [11, 12], are fulfilled. A more precise definition of lesion types and locations according to the recommendations of an international expert group [13] is discussed in the supplementary material. Spinal cord signal abnormalities are seen in up to 92 % of MS patients [14-16] and are primarily located in the cervical spine [15]. The recommendations of the MAGNIMS-CMSC-NAIMS working group published in 2021 [11] explicitly recommend the use of structured reporting for MS patients.Therefore, a reporting template for evaluating MRI examinations of the brain and spinal cord of patients with MS was created as part of the BMBF-funded DIFUTURE consortium in consensus with neuroradiological and neurological experts in concordance with the recommendations mentioned above [11] and was made available for broad use (https://github.com/DRGagit/ak_befundung). The goal is to facilitate efficient and comprehensive evaluation of patients with MS in the primary diagnostic workup and follow-up imaging. These reporting templates are consensus-based recommendations and do not make any claim to general validity or completeness. The information technology working group (@GIT) of the German Radiological Society and the German Society for Neuroradiology strive to keep the reporting templates presented here up-to-date with respect to new research data and recommendations of the MAGNIMS-CMSC-NAIMS group [11]. KEY POINTS:: · consensus-based reporting templates. · template for the structured reporting of MRI examinations of patients with multiple sclerosis. · structured reporting might facilitate communication between neuroradiologists and referring disciplines. CITATION FORMAT: · Riederer I, Mühlau M, Wiestler B et al. Structured Reporting in Multiple Sclerosis - Consensus-Based Reporting Templates for Magnetic Resonance Imaging of the Brain and Spinal Cord. Fortschr Röntgenstr 2023; 195: 135 - 138.

Intraoperative ultrasonography in laminectomy for degenerative cervical spondylotic myelopathy: a clinical and radiological evaluation.

BACKGROUND: The incidence of cervical myelopathy due to spinal stenosis is constantly growing in an aging population. Especially in multisegmental disease, dorsal laminectomy is the intervention of choice. Intraoperative imaging with ultrasound might provide additional information about extent and sufficiency of spinal cord decompression. METHODS: In this prospective study, the width of the subarachnoid space was systematically measured by intraoperative ultrasound at predefined sites at the cranial and caudal edge of decompression in axial and sagittal reconstruction. These data were compared with corresponding sites on postoperative T2-weighted MRI imaging. In addition, the functional outcome was assessed by modified Japanese Orthopaedic Association (mJOA) score. A historical patient cohort treated without ultrasound-guided laminectomy served as control group. RESULTS: Altogether, 29 patients were included. According to mJOA score at last follow-up, 7/29 patients reported stable symptoms and 21/29 patients showed a substantial benefit with no or minor residual neurological deficits. One patient suffered from a new C5 palsy. Intraoperative ultrasound-guided posterior decompression provided excellent overview in all cases. Measurement of the width of the subarachnoid space acquired by intraoperative ultrasound and postoperative MRI images showed a very high correlation, especially at the cranial level (p < 0.001, r = 0.880). Bland-Altman analysis showed that most patients were within the 1.96 × SD limits of agreement throughout all measurements. No ultrasound procedure-related complications were observed. Compared to a historical cohort of 27 patients, no significant differences were found regarding functional outcome (p = 0.711). CONCLUSION: Intraoperative sonography visualises the surgically achieved restoration of the subarachnoid space in good correlation with postoperative MRI and might serve as a fast, precise and reliable tool for intraoperative imaging in cervical laminectomy. However, we could not demonstrate a clinical benefit with regard to functional outcome.

Diagnosis and follow-up evaluation of central nervous system vasculitis: an evaluation of vessel-wall MRI findings.

OBJECTIVE: To approach the clinical value of MRI with vessel wall imaging (VWI) in patients with central nervous system vasculitis (CNSV), we analyzed patterns of VWI findings both at the time of initial presentation and during follow-up. METHODS: Stenoocclusive lesions, vessel-wall contrast enhancement (VW-CE) and diffusion-restricted lesions were analyzed in patients with a diagnosis of CNSV. On available VWI follow-up, progression, regression or stability of VW-CE were evaluated and correlated with the clinical status. RESULTS: Of the 45 patients included, 28 exhibited stenoses visible on MR angiography (MRA-positive) while 17 had no stenosis (MRA-negative). VW-CE was found in 2/17 MRA-negative and all MRA-positive patients (p < 0.05). 79.1% (53/67) of stenoses showed VW-CE. VW-CE was concentric in 88.3% and eccentric in 11.7% of cases. Diffusion-restricted lesions were found more frequently in relation to stenoses with VW-CE than without VW-CE (p < 0.05). 48 VW-CE lesions in 23 patients were followed over a median time of 239.5 days. 13 VW-CE lesions (27.1%) resolved completely, 14 (29.2%) showed partial regression, 17 (35.4%) remained stable and 4 (8.3%) progressed. 22/23 patients received immunosuppressive therapy for the duration of follow-up. Patients with stable or progressive VW-CE were more likely (p < 0.05) to have a relapse (14/30 cases) than patients with partial or complete regression of VW-CE (5/25 cases). CONCLUSION: Concentric VW-CE is a common finding in medium/large-sized vessel CNSV. VW-CE might represent active inflammation in certain situations. However, follow-up VWI findings proved ambiguous as persisting VW-CE despite immunosuppressive therapy and clinical remission was a frequent finding.

Late Thrombectomy in Clinical Practice : Retrospective Application of DAWN/DEFUSE3 Criteria within the German Stroke Registry.

BACKGROUND AND PURPOSE: To provide real-world data on outcome and procedural factors of late thrombectomy patients. METHODS: We retrospectively analyzed patients from the multicenter German Stroke Registry. The primary endpoint was clinical outcome on the modified Rankin scale (mRS) at 3 months. Trial-eligible patients and the subgroups were compared to the ineligible group. Secondary analyses included multivariate logistic regression to identify predictors of good outcome (mRS ≤ 2). RESULTS: Of 1917 patients who underwent thrombectomy, 208 (11%) were treated within a time window ≥ 6-24 h and met the baseline trial criteria. Of these, 27 patients (13%) were eligible for DAWN and 39 (19%) for DEFUSE3 and 156 patients were not eligible for DAWN or DEFUSE3 (75%), mainly because there was no perfusion imaging (62%; n = 129). Good outcome was not significantly higher in trial-ineligible (27%) than in trial-eligible (20%) patients (p = 0.343). Patients with large trial-ineligible CT perfusion imaging (CTP) lesions had significantly more hemorrhagic complications (33%) as well as unfavorable outcomes. CONCLUSION: In clinical practice, the high number of patients with a good clinical outcome after endovascular therapy ≥ 6-24 h as in DAWN/DEFUSE3 could not be achieved. Similar outcomes are seen in patients selected for EVT ≥ 6 h based on factors other than CTP. Patients triaged without CTP showed trends for shorter arrival to reperfusion times and higher rates of independence.

TSPO PET imaging of natalizumab-associated progressive multifocal leukoencephalopathy.

Progressive multifocal leukoencephalopathy (PML) is a severe infection of the CNS caused by the polyomavirus JC that can occur in multiple sclerosis patients treated with natalizumab. Clinical management of patients with natalizumab-associated PML is challenging not least because current imaging tools for the early detection, longitudinal monitoring and differential diagnosis of PML lesions are limited. Here we evaluate whether translocator protein (TSPO) PET imaging can be applied to monitor the inflammatory activity of PML lesions over time and differentiate them from multiple sclerosis lesions. For this monocentre pilot study we followed eight patients with natalizumab-associated PML with PET imaging using the TSPO radioligand 18F-GE-180 combined with frequent 3 T MRI. In addition we compared TSPO PET signals in PML lesions with the signal pattern of multiple sclerosis lesions from 17 independent multiple sclerosis patients. We evaluated the standardized uptake value ratio as well as the morphometry of the TSPO uptake for putative PML and multiple sclerosis lesions areas compared to a radiologically unaffected pseudo-reference region in the cerebrum. Furthermore, TSPO expression in situ was immunohistochemically verified by determining the density and cellular identity of TSPO-expressing cells in brain sections from four patients with early natalizumab-associated PML as well as five patients with other forms of PML and six patients with inflammatory demyelinating CNS lesions (clinically isolated syndrome/multiple sclerosis). Histological analysis revealed a reticular accumulation of TSPO expressing phagocytes in PML lesions, while such phagocytes showed a more homogeneous distribution in putative multiple sclerosis lesions. TSPO PET imaging showed an enhanced tracer uptake in natalizumab-associated PML lesions that was present from the early to the chronic stages (up to 52 months after PML diagnosis). While gadolinium enhancement on MRI rapidly declined to baseline levels, TSPO tracer uptake followed a slow one phase decay curve. A TSPO-based 3D diagnostic matrix taking into account the uptake levels as well as the shape and texture of the TSPO signal differentiated >96% of PML and multiple sclerosis lesions. Indeed, treatment with rituximab after natalizumab-associated PML in three patients did not affect tracer uptake in the assigned PML lesions but reverted tracer uptake to baseline in the assigned active multiple sclerosis lesions. Taken together our study suggests that TSPO PET imaging can reveal CNS inflammation in natalizumab-associated PML. TSPO PET may facilitate longitudinal monitoring of disease activity and help to distinguish recurrent multiple sclerosis activity from PML progression.

Extended stereotactic brain biopsy in suspected primary central nervous system angiitis: good diagnostic accuracy and high safety.

OBJECTIVE: To evaluate the diagnostic accuracy and safety of extended stereotactic brain biopsy (ESBB) in a single center cohort with suspected primary angiitis of the central nervous system (PACNS). METHODS: A standardized stereotactic biopsy targeting MRI-positive lesions and collecting samples from the meninges and the cortex as well as from the white matter was performed in 23 patients with clinically suspected PACNS between 2010 and 2017. The relationship between biopsy yield and clinical characteristics, cerebrospinal fluid parameters, MR-imaging, time point of biopsy and exact localization of biopsy as well as number of tissue samples were examined. RESULTS: PACNS was confirmed in 7 of 23 patients (30.4%). Alternative diagnoses were identified in 7 patients (30%). A shorter time period between the onset or worsening of symptoms (p = 0.018) and ESBB significantly increased the diagnostic yield. We observed only minor and transient postoperative complications in 3 patients (13.0%). ESBB led to a direct change of the therapeutic regime in 13 of 23 patients (56.5%). Careful neuropathological analysis furthermore revealed that cortical samples were crucial in obtaining a diagnosis. CONCLUSION: ESBB is a safe approach with good feasibility, even in critically ill patients, and high diagnostic accuracy in patients with suspected PACNS changing future therapies in 13 of 23 patients (56.5%). Early biopsy after symptom onset/worsening is crucial and (sub)acute MRI-lesions should be targeted with a particular need for biopsy samples from the cortical layer.

The clinical value of ceMRA versus DSA for follow-up of intracranial aneurysms treated by coil embolization: an assessment of occlusion classifications and impact on treatment decisions.

OBJECTIVE: The aim of this study was a detailed analysis of the value of contrast-enhanced magnetic resonance angiography (ceMRA) compared to digital subtraction angiography (DSA) for follow-up imaging of intracranial aneurysms treated by coil embolization. METHODS: Patients with coiled aneurysms and follow-up exams including both DSA and 3 T ceMRA were retrospectively identified. In blinded readings, both modalities were graded according to the modified Raymond-Roy classification (MRRC) and the Meyers scale. Additionally, readers were asked to make a decision regarding retreatment/follow-up based on the respective imaging findings. RESULTS: The study comprised 92 patients harboring 102 coiled aneurysms. There was good intermethod agreement of DSA and ceMRA concerning both the MRRC (κ = 0.64) and the Meyers scale (κ = 0.74). Agreement regarding occlusion of < 90% of the aneurysm (Meyers grade ≥ 2) was very good (κ = 0.87). Regarding the detection of a remnant with contrast between the coil mass and the aneurysm wall (MRRC IIIb), there were 12 discrepant findings and agreement was good (κ = 0.70). Comparing treatment/follow-up decisions, the two methods agreed very well (κ = 0.92). In seven patients with discrepant treatment decisions, the authors concurred with DSA in four cases and with ceMRA in three cases when evaluating both modalities together. Interval aneurysm growth was found in more cases with ceMRA (n = 19) than with DSA (n = 16). CONCLUSIONS: CeMRA is very unlikely to miss a relevant aneurysm remnant and thus could be suitable as the primary follow-up method. In case of remnant growth or recurrence, however, additional DSA might be required to guide treatment decisions. KEY POINTS: • There is high accordance between ceMRA and DSA regarding the evaluation of intracranial aneurysms treated by endovascular coil embolization, but closer analysis also revealed relevant differences. • CeMRA could be suitable as the primary follow-up imaging modality, potentially eliminating the need for routine DSA. • DSA will still be required in case of aneurysm remnant growth or recurrence as detected by ceMRA.

CT-Based Classification of Acute Cerebral Edema: Association with Intracranial Pressure and Outcome.

BACKGROUND AND PURPOSE: Brain edema after acute cerebral lesions may lead to raised intracranial pressure (ICP) and worsen outcome. Notwithstanding, no CT-based scoring system to quantify edema formation exists. This retrospective correlative analysis aimed to establish a valid and definite CT score quantifying brain edema after common acute cerebral lesions. METHODS: A total of 169 CT investigations in 60 patients were analyzed: traumatic brain injury (TBI; n = 47), subarachnoid hemorrhage (SAH; n = 70), intracerebral hemorrhage (ICH; n = 42), and ischemic stroke (n = 10). Edema formation was classified as 0: no edema, 1: focal edema confined to 1 lobe, 2: unilateral edema > 1 lobe, 3: bilateral edema, 4: global edema with disappearance of sulcal relief, and 5: global edema with basal cisterns effacement. ICP and Glasgow Outcome Score (GOS) were correlated to edema formation. RESULTS: Median ICP values were 12.0, 14.0, 14.9, 18.2, and 25.9 mm Hg in grades 1-5, respectively. Edema grading significantly correlated with ICP (r = .51; P < .0001) in focal and global cerebral edema, particularly in patients with TBI, SAH, and ICH (r = .5, P < .001; r = .5; P < .0001; r = .6, P < .0001, respectively). At discharge, 23.7% of patients achieved a GOS of 5 or 4, 65.0% reached a GOS of 3 or 2, and 11.9% died (GOS 1). CT-score of cerebral edema in all patients correlated with outcome (r = -.3, P = .046). CONCLUSION: The proposed CT-based grading of extent of cerebral edema significantly correlated with ICP and outcome in TBI, SAH, and ICH patients and might be helpful for standardized description of CT-images and as parameter for clinical studies, for example, measuring effects of antiedematous therapies.

Artificial Intelligence Algorithm Detecting Lung Infection in Supine Chest Radiographs of Critically Ill Patients With a Diagnostic Accuracy Similar to Board-Certified Radiologists.

OBJECTIVES: Interpretation of lung opacities in ICU supine chest radiographs remains challenging. We evaluated a prototype artificial intelligence algorithm to classify basal lung opacities according to underlying pathologies. DESIGN: Retrospective study. The deep neural network was trained on two publicly available datasets including 297,541 images of 86,876 patients. PATIENTS: One hundred sixty-six patients received both supine chest radiograph and CT scans (reference standard) within 90 minutes without any intervention in between. MEASUREMENTS AND MAIN RESULTS: Algorithm accuracy was referenced to board-certified radiologists who evaluated supine chest radiographs according to side-separate reading scores for pneumonia and effusion (0 = absent, 1 = possible, and 2 = highly suspected). Radiologists were blinded to the supine chest radiograph findings during CT interpretation. Performances of radiologists and the artificial intelligence algorithm were quantified by receiver-operating characteristic curve analysis. Diagnostic metrics (sensitivity, specificity, positive predictive value, negative predictive value, and accuracy) were calculated based on different receiver-operating characteristic operating points. Regarding pneumonia detection, radiologists achieved a maximum diagnostic accuracy of up to 0.87 (95% CI, 0.78-0.93) when considering only the supine chest radiograph reading score 2 as positive for pneumonia. Radiologist's maximum sensitivity up to 0.87 (95% CI, 0.76-0.94) was achieved by additionally rating the supine chest radiograph reading score 1 as positive for pneumonia and taking previous examinations into account. Radiologic assessment essentially achieved nonsignificantly higher results compared with the artificial intelligence algorithm: artificial intelligence-area under the receiver-operating characteristic curve of 0.737 (0.659-0.815) versus radiologist's area under the receiver-operating characteristic curve of 0.779 (0.723-0.836), diagnostic metrics of receiver-operating characteristic operating points did not significantly differ. Regarding the detection of pleural effusions, there was no significant performance difference between radiologist's and artificial intelligence algorithm: artificial intelligence-area under the receiver-operating characteristic curve of 0.740 (0.662-0.817) versus radiologist's area under the receiver-operating characteristic curve of 0.698 (0.646-0.749) with similar diagnostic metrics for receiver-operating characteristic operating points. CONCLUSIONS: Considering the minor level of performance differences between the algorithm and radiologists, we regard artificial intelligence as a promising clinical decision support tool for supine chest radiograph examinations in the clinical routine with high potential to reduce the number of missed findings in an artificial intelligence-assisted reading setting.

Patient reported long-term outcome after endovascular therapy of indirect dural carotid cavernous fistulas.

PURPOSE: Patient-reported long-term follow-up after endovascular treatment of indirect carotid cavernous fistulas is important, but rarely addressed in literature. We report on this issue with a special focus on the patient's view and its impact on the indication evaluation process. METHODS: We retrospectively reviewed the records of all patients (n = 33) with a minimum follow-up interval of at least 36 and up to 166 months after endovascular treatment of an indirect carotid cavernous fistula (Barrow B-D) at our institution (treated from 01/2003 to 06/2015). We determined treatment details including primary therapy success and complication rate and quote the patient's subjective perception of the long-term treatment success using a standardized interview form. RESULTS: As a primary result the fistula was completely occluded in 25/33 cases (76%), while a downgrading was achieved in 8/33 (24%) of the cases. Secondary occlusion was observed in three out of eight patients (38%). In the long-term interview (response rate: 91%, median follow-up interval: 114 months) 87% of the patients reported high satisfaction with the long-term therapy result. Endovascular treatment achieved a sustainable relief from all eye-related symptoms in 89% and from pulsatile tinnitus in 57% of the cases. CONCLUSIONS: In addition to good results in terms of angiographic and clinical cure, endovascular treatment is also perceived as beneficial by most of the patients. This is another important argument in favor of an endovascular treatment.

Ultrafast Brain Magnetic Resonance Imaging in Acute Neurological Emergencies: Diagnostic Accuracy and Impact on Patient Management.

OBJECTIVES: The aim of this study was to investigate diagnostic accuracy and impact on patient management of an ultrafast (4:33 minutes/5 sequences) brain magnetic resonance imaging (MRI) protocol for the detection of intracranial pathologies in acute neurological emergencies. MATERIALS AND METHODS: Four hundred forty-nine consecutive emergency patients with acute nontraumatic neurological symptoms were evaluated for this institutional review board-approved prospective single-center trial. Sixty patients (30 female, 30 male; mean age, 61 years) with negative head CT were included and underwent emergency brain MRI at 3 T subsequent to CT. MRI included the ultrafast protocol (ultrafast-MRI; sag T1 GRE, ax T2 TSE, ax T2 TSE Flair, ax T2* EPI-GRE, ax DWI SS-EPI; TA, 5 minutes) and an equivalent standard-length protocol (TA, 15 minutes) as reference standard. Two blinded board-certified neuroradiologists independently analyzed the MRI with regard to image quality (1, nondiagnostic; 2, substantial artifacts; 3, satisfactory; 4, minor artifacts; 5, no artifacts) and intracranial pathologies. Sensitivity and specificity for the detection of intracranial pathologies were calculated accordingly. RESULTS: Ninety-three additional intracranial lesions (acute ischemia, n = 21; intracranial hemorrhage/microbleeds, n = 27; edema, n = 2; white matter lesion, n = 38; chronic infarction, n = 3; others, n = 2) were detected by ultrafast-MRI, whereas 101 additional intracranial lesions were detected by the standard-length protocol (acute ischemia, n = 24; intracranial hemorrhage/microbleeds, n = 32; edema, n = 2; white matter lesion, n = 38; chronic infarction, n = 3; others, n = 2). Image quality was equivalent to the standard-length protocol. Ultrafast-MRI demonstrated high diagnostic accuracy (sensitivity, 0.939 [0.881-0.972]; specificity, 1.000 [0.895-1.000]) for the detection of intracranial pathologies. MRI led to a change in patient management in 10% compared with the initial CT. CONCLUSIONS: Ultrafast-MRI enables time-optimized diagnostic workup in acute neurological emergencies at high sensitivity and specificity compared with a standard-length protocol, with direct impact on patient management. Ultrafast MRI protocols are a powerful tool in the emergency setting and may be implemented on various scanner types based on the optimization of individual acquisition parameters.

Measurement of structural integrity of the spinal cord in patients with amyotrophic lateral sclerosis using diffusion tensor magnetic resonance imaging.

BACKGROUND: The value of conventional magnetic resonance imaging (MRI) for amyotrophic lateral sclerosis (ALS) is low. Functional and quantitative MRI could be more accurate. We aimed to examine the value of diffusion tensor imaging (DTI) with fractional anisotropy (FA) measurements of the cervical and upper thoracic spinal cord in patients with ALS. PATIENTS AND METHODS: Fourteen patients with ALS and 15 sex- and age-matched controls were examined with DTI at a 3T MRI scanner. Region-of-interest (ROI) based fractional anisotropy measurements were performed at the levels C2-C4, C5-C7 and Th1-Th3. ROIs were placed at different anatomical locations of the axial cross sections of the spinal cord. RESULTS: FA was significantly reduced in ALS patients in anterolateral ROIs and the whole cross section at the C2-C4 level and the cross section of the Th1-Th3 level. There was a trend towards a statistically significant FA reduction in the anterolateral ROIs at the C5-C7 level in ALS patients. No significant differences between patients and controls were found in posterior ROIs. CONCLUSION: FA was reduced in ROIs representing the motor tracts in ALS patients. DTI with FA measurements is a promising method in this circumstance. However, for DTI to become a valuable and established method in the diagnostic workup of ALS, larger studies and further standardisation are warranted.

Endovascular therapy of direct dural carotid cavernous fistulas - A therapy assessment study including long-term follow-up patient interviews.

PURPOSE: Endovascular embolization nowadays is a well-established treatment option for direct carotid cavernous fistulas (dCCF, Barrow Type A). There are many publications on the complication and success rates of this method. However, little is known on the patients´ opinion on the treatment result after several years. We report on this issue also including the "pioneer patients" treated almost two decades ago. METHODS: We retrospectively reviewed the records of all patient (n = 25) with a more than 24 months follow-up interval after endovascular treatment of a dCCF at our institution from 01/1999 to 08/2018. We determined primary therapy success, complication rate, state of the fistula in the last imaging follow-up and quoted the patient's subjective perception of the long-term treatment success using a standardized interview form. RESULTS: Occlusion rate in the last imaging follow up was 96% (24/25) with a complication rate of 8% (2/25). The response rate on our interview request was 96% (24/25) with a rate of considered feedback of 84% (21/25 patients). Duration of our observation interval for the patient reported outcome was 143 months / 11 years (median, range: 35-226 m / 2-18 y). Most of them (21/25, 84%) felt they benefited from the treatment. CONCLUSIONS: Endovascular supply of dCCF is a highly effective treatment method leading to a sustainable therapy success with long-lasting stable subjective benefit even to our "pioneer patients" treated almost two decades ago.

Radiation dose and image quality in intraoperative CT (iCT) angiography of the brain with stereotactic head frames.

OBJECTIVES: Intraoperative CT (iCT) angiography of the brain with stereotactic frames is an integral part of navigated neurosurgery. Validated data regarding radiation dose and image quality in these special examinations are not available. We therefore investigated two iCT protocols in this IRB-approved study. METHODS: Retrospective analysis of patients, who received a cerebral stereotactic iCT angiography on a 128 slice CT scanner between February 2016 and December 2017. In group A, automated tube current modulation (ATCM; reference value 410 mAs) and automated tube voltage selection (reference value 120 kV) were enabled, and only examinations with a selected voltage of 120 kV were included. In group B, fixed parameters were applied (300 mAs, 120 kV). Radiation dose was measured by assessing the volumetric CT dose index (CTDIvol), dose length product (DLP) and effective dose (ED). Signal-to-noise ratio (SNR) and image noise were assessed for objective image quality, visibility of arteries and grey-white differentiation for subjective image quality. RESULTS: Two hundred patients (n = 100 in each group) were included. In group A, median selected tube current was 643 mAs (group B, 300 mAs; p < 0.001). Median values of CTDIvol, DLP and ED were 91.54 mGy, 1561 mGy cm and 2.97 mSv in group A, and 43.15 mGy, 769 mGy cm and 1.46 mSv in group B (p < 0.001). Image quality did not significantly differ between groups (p > 0.05). CONCLUSIONS: ATCM yielded disproportionally high radiation dose due to substantial tube current increase at the frame level, while image quality did not improve. Thus, ATCM should preferentially be disabled. KEY POINTS: • Automated tube current modulation (ATCM) yields disproportionally high radiation dose in intraoperative CT angiography of the brain with stereotactic head frames. • ATCM does not improve overall image quality in these special examinations. • ATCM is not yet optimised for CT angiography of the brain with major extracorporeal foreign materials within the scan range.

Intracranial Rescue Stent Angioplasty After Stent-Retriever Thrombectomy : Multicenter Experience.

PURPOSE: Stent-retriever thrombectomy (SRT) for acute intracranial large artery occlusion (LAO) may not result in permanent recanalization in rare cases, e.g. due to an underlying stenosis or dissection. In this specific patient group, rescue stent angioplasty (RSA) may be the only treatment option to achieve permanent vessel patency and potentially a good clinical outcome. To date, the experience with RSA is limited. METHODS: In this retrospective analysis, interventional and clinical data of patients with acute intracranial LAO of the anterior and posterior circulation who underwent RSA after SRT due to an underlying lesion between 2012-2017 in four neurovascular centers were studied. RESULTS: In this study 34 patients (mean age 67 years) were included whereby 18 patients had anterior circulation LAO and 16 patients posterior circulation LAO. The SRT maneuver count ranged between 1 and 15 (median 2). Indications for RSA were an immediate re-occlusion in 25 (74%), and a persistent high-grade stenosis in 9 patients (26%). The RSA was technically feasible in 33 patients (97%). A mTICI 2b/3 result was obtained in 26 patients (76%). Median onset-to-recanalization time was 248 min (range 80-650 min). After 3 months 10/34 patients (29%) had a good clinical outcome (modified Rankin Scale, mRS 0-2). In detail, 4/18 patients (22%) with anterior circulation LAO and 6/16 patients (38%) with posterior circulation LAO were functionally independent. CONCLUSION: The use of RSA can be considered for acute intracranial LAO in cases with immediate re-occlusion or high-grade stenosis after SRT alone.

Challenges in HSV encephalitis: normocellular CSF, unremarkable CCT, and atypical MRI findings.

PURPOSE: Herpes simplex virus (HSV) encephalitis continues to be the most common form of sporadic lethal encephalitis worldwide. The wide spectrum of clinical presentations and laboratory findings often poses a diagnostic challenge for physicians which might delay administration of life-saving therapy with acyclovir. Atypical presentations of HSV encephalitis have become increasingly prevalent with better diagnostic techniques and have not been well studied. METHODS: We retrospectively evaluated all consecutive PCR-proven HSV encephalitis cases treated at the Hospital of the Ludwig-Maximilians-University in Munich, Germany from January 1, 2013 to February 28, 2018. RESULTS: We included 18 patients with PCR-proven HSV encephalitis. The most common clinical features were altered mental status (77.8%), focal neurologic deficits (72.2%) and fever (72.2%). Remarkably, four of these patients (22.2%) had a normocellular cerebrospinal fluid (CSF) on admission. Electroencephalography and magnetic resonance imaging abnormalities were highly sensitive for HSV encephalitis independent of CSF cell count. Striking atypical findings on MRI were extensive global brain swelling and severe brainstem involvement in single patients. Of note, initial CT scans were normal in 11 out of 16 patients (68.8%). All patients were treated with acyclovir. Three patients still developed a clinical deterioration under therapy with acyclovir with one patient requiring decompressive craniotomy due to bilateral space-occupying temporal lobe hemorrhage. 94.4% of the patients survived but only 38.9% were discharged with a good clinical outcome (Glasgow Outcome Score = 5). CONCLUSION: Atypical presentations of HSV encephalitis seem to be more common than previously thought and physicians should apply a high level of clinical suspicion and a low threshold to initiate life-saving acyclovir therapy in suspected cases.

The Value of Supine Chest X-Ray in the Diagnosis of Pneumonia in the Basal Lung Zones.

RATIONALE AND OBJECTIVES: Basal lung opacities are frequently observed on supine chest x-ray (SCXR) of intensive care patients, causing insecurity among clinicians and radiologists. We sought to determine the diagnostic accuracy of SCXR for basal pneumonia. MATERIALS AND METHODS: We identified 172 patients who received both SCXR and computed tomography within 1 hour. Two readers examined the SCXR and rated findings in both basal zones according to the following scale: 0 = "no pneumonia," 1 = "possible pneumonia," 2 = "highly suspected pneumonia." Computed tomography served as standard of reference. Sensitivity, specificity, and positive and negative predictive values (PPV/NPV) were calculated once pooling 0 and 1 as negative and once pooling 1 and 2 as positive finding. RESULTS: When pooling 0 and 1 as negative, sensitivity was 0.45 (right)/0.38 (left), specificity was 0.94/0.97, PPV was 0.76/0.79, and NPV was 0.81/0.84. When pooling 1 and 2 as positive, sensitivity was 0.80/0.75, specificity was 0.62/0.58, PPV was 0.45/0.35, and NPV was 0.88/0.89. The most common findings in false-positive cases were combined pleural effusions and lower lobe atelectasis. CONCLUSIONS: Interpreting only highly suspicious basal opacities as pneumonia considerably increases the PPV with almost constant NPV. Clinicians and radiologists should be aware of the limitations of SCXR regarding basal pneumonia.