Neurocognitive change over the course of a multiday external lumbar drain trial in patients with suspected normal pressure hydrocephalus.

Objective: To characterize neurocognitive response to cerebrospinal fluid (CSF) diversion during a multiday external lumbar drainage (ELD) trial in patients with suspected normal pressure hydrocephalus (NPH). Methods: Inpatients (N = 70) undergoing an ELD trial as part of NPH evaluation participated. Cognition and balance were assessed using standardized measures before and after a three-day ELD trial. Cognitive change pre- to post-ELD trial was assessed in relation to change in balance, baseline neuroimaging findings, NPH symptoms, demographics, and other disease-relevant clinical parameters. Results: Multiday ELD resulted in significant cognitive improvement (particularly on measures of memory and language). This improvement was independent of demographics, test-retest interval, number of medical and psychiatric comorbidities, NPH symptom duration, estimated premorbid intelligence, baseline level of cognitive impairment, cerebrovascular disease burden, degree of ventriculomegaly, or other NPH-related morphological brain alterations. Balance scores evidenced a greater magnitude of improvement than cognitive scores and were weakly, but positively correlated with cognitive change scores. Conclusions: Findings suggest that cognitive improvement associated with a multiday ELD trial can be sufficiently captured with bedside neurocognitive testing. These findings support the utility of neuropsychological consultation, along with balance assessment, in informing clinical decision-making regarding responsiveness to temporary CSF diversion for patients undergoing elective NPH evaluation. Implications for the understanding of neuroanatomical and cognitive underpinnings of NPH are discussed.

Utilization of a cloud-based radiology analytics platform to monitor imaging volumes at a large tertiary center.

Rationale and objective: In this study, we evaluate the ability of a novel cloud-based radiology analytics platform to continuously monitor imaging volumes at a large tertiary center following institutional protocol and policy changes. Materials and methods: We evaluated response to environmental factors through the lens of the COVID-19 pandemic. Analysis involved 11 CT/18 MR imaging systems at a large tertiary center. A vendor neutral, cloud-based analytics tool (CBRAP) was used to retrospectively collect information via DICOM headers on imaging exams between Oct. 2019 to Aug. 2021. Exams were stratified by modality (CT or MRI) and organized by body region. Pre-pandemic scan volumes (Oct 2019-Feb. 2010) were compared with volumes during/after two waves of COVID-19 in Illinois (Mar. to May 2020 & Oct. to Dec. 2020) using a t-test or Mann-Whitney U test. Results: The CBRAP was able to analyze 169,530 CT and 110,837 MR images, providing a detailed snapshot of baseline and post-pandemic CT and MR imaging across the radiology enterprise at our tertiary center. The CBRAP allowed for further subdivision in its reporting, showing monthly trends in average scan volumes specifically in the head, abdomen, spine, MSK, thorax, neck, GU system, or breast. Conclusion: The CBRAP retrieved data for 300,000 + imaging exams across multiple modalities at a large tertiary center in a highly populated, urban environment. The ability to analyze large imaging volumes across multiple waves of COVID-19 and evaluate quality-improvement endeavors/imaging protocol changes displays the usefulness of the CBRAP as an advanced imaging analytics tool.

Tumor-associated alterations in white matter connectivity have prognostic significance in MGMT-unmethylated glioblastoma.

PURPOSE: We investigated the prognostic significance of tumor-associated white matter (TA-WM) tracts in glioblastoma (GBM) using magnetic resonance-diffusion tensor imaging (MR-DTI). We hypothesized that (1) TA-WM tracts harbor microscopic disease not targeted through surgery or radiotherapy (RT), and (2) the greater the extent of TA-WM involvement, the worse the survival outcomes. METHODS: We studied a retrospective cohort of 76 GBM patients. TA-WM tracts were identified by MR-DTI fractional anisotropy (FA) maps. For each patient, 22 TA-WM tracts were analyzed and each tract was graded 1-3 based on FA. A TA-WM score (TA-WMS) was computed based on number of involved tracts and corresponding FA grade of involvement. Kaplan-Meier statistics were utilized to determine survival outcomes, log-rank test was used to compare survival between groups, and Cox regression was utilized to determine prognostic variables. RESULTS: For the MGMT-unmethylated cohort, there was a decrease in OS for increasing TA-WMS (median OS 16.5 months for TA-WMS 0-4; 13.6 months for TA-WMS 5-8; 7.3 months for TA-WMS > 9; p = 0.0002). This trend was not observed in the MGMT-methylated cohort. For MGMT-unmethylated patients with TA-WMS > 6 and involvement of tracts passing through brainstem or contralateral hemisphere, median OS was 8.3 months versus median OS 14.1 months with TA-WMS > 6 but not involving aforementioned critical tracts (p = 0.003 log-rank test). For MGMT-unmethylated patients, TA-WMS was predictive of overall survival in multivariate analysis (HR = 1.14, 95% CI 1.03-1.27, p = 0.012) while age, gender, and largest tumor dimension were non-significant. CONCLUSION: Increased TA-WMS and involvement of critical tracts are associated with decreased overall survival in MGMT-unmethylated GBM.

Multimodal Presurgical Evaluation of Medically Refractory Focal Epilepsy in Adults: An Update for Radiologists.

Surgery is a potentially curative treatment option for patients with medically refractory focal epilepsy. Advanced neuroimaging modalities often improve surgical outcomes by contributing key information during the highly individualized surgical planning process and intraoperative localization. Hence, neuroradiologists play an integral role in the multidisciplinary management team. In this review, we initially present the conceptual background and practical framework of the presurgical evaluation process, including a description of the surgical treatment approaches used for medically refractory focal epilepsy in adults. This background is followed by an overview of the advanced modalities commonly used during the presurgical workup at level IV epilepsy centers, including diffusion imaging techniques, blood oxygenation level-dependent functional MRI (fMRI), PET, SPECT, and subtraction ictal SPECT, and by introductions to 7-T MRI and electrophysiologic techniques including electroencephalography and magnetoencephalography. We also provide illustrative case examples of multimodal neuroimaging including PET/MRI, PET/MRI-diffusion-tensor imaging (DTI), subtraction ictal SPECT, and image-guided stereotactic planning with fMRI-DTI.

Advancements in Positron Emission Tomography/Magnetic Resonance Imaging and Applications to Diagnostic Challenges in Neuroradiology.

Since the clinical adoption of magnetic resonance (MR) in medical imaging, MR has proven to be a workhorse in diagnostic neuroradiology, with the ability to provide superb anatomic detail as well as additional functional and physiologic data, depending on the techniques utilized. Positron emission tomography/computed tomography has also shown irreplaceable diagnostic value in certain disease processes of the central nervous system by providing molecular and metabolic information through the development of numerous disease-specific PET tracers, many of which can be utilized as a diagnostic technique in and of themselves or can provide a valuable adjunct to information derived from MR. Despite these advances, many challenges still remain in neuroradiology, particularly in malignancy, neurodegenerative disease, epilepsy, and cerebrovascular disease. Through improvements in attenuation correction, motion correction, and PET detectors, combining the 2 modalities of PET and MR through simultaneous imaging has proven feasible and allows for improved spatial and temporal resolution without compromising either of the 2 individual modalities. The complementary information offered by both technologies has provided increased diagnostic accuracy in both research and many clinical applications in neuroradiology.

Can loss of the swallow tail sign help distinguish between Parkinson Disease and the Parkinson-Plus syndromes?

PURPOSE: To determine if loss of the swallow tail sign (STS) can distinguish Parkinson Disease (PD) from the Parkinson-Plus syndromes. METHODS: Twenty-five patients with PD, 21 with Parkinson-Plus syndromes, and 14 control patients were included. Presence of the STS was assessed. RESULTS: The STS was present in 79% of controls, statistically greater than the PD/Parkinson-Plus patients. There was no difference in the presence of the STS between the PD/Parkinson-Plus subgroups or when scanning at 1.5 T or 3 T. CONCLUSIONS: Loss of the STS could not distinguish between PD and Parkinson-Plus patients. The STS can be identified at both 1.5 T and 3 T.

Efficacy and safety of novel oral anticoagulants in patients with cervical artery dissections.

BACKGROUND: American and European guidelines support antiplatelet agents and anticoagulants as reasonable treatments of cervical artery dissection (CAD), though randomized clinical trials are lacking. The utility of novel oral anticoagulants (NOAC), effective in reducing embolic stroke risk in non-valvular atrial fibrillation (NVAF), has not been reported in patients with CAD. We report on the use, safety, and efficacy of NOACs in the treatment of CAD. METHODS: We retrospectively identified patients diagnosed with CAD at a single academic center between January 2010 and August 2013. Patients were categorized by their antithrombotic treatment at hospital discharge with a NOAC (dabigatran, rivaroxaban, or apixaban), traditional anticoagulant (AC: warfarin or treatment dose low-molecular weight heparin), or antiplatelet agent (AP: aspirin, clopidogrel, or aspirin/extended-release dypyridamole). Using appropriate tests, we compared the baseline medical history, presenting clinical symptoms and initial radiographic characteristics among patients in the 3 treatment groups. We then evaluated for the following outcomes: recurrent stroke, vessel recanalization, and bleeding complications. p values <0.05 were considered significant. RESULTS: Of the 149 included patients (mean age 43.4 years; 63.1% female; 70.5% vertebral artery CAD), 39 (26.2%), 70 (47.0%), and 40 (26.8%) were treated with a NOAC, AC, and AP, respectively. More patients with severe stenosis or occlusion were treated with NOAC than with AC or AP (61.8 vs. 60.0 vs. 22.5%, p = 0.002). Other baseline clinical and radiographic findings, including the presence of acute infarction and hematoma, did not differ between the 3 treatment groups. One hundred and thirty-five (90.6%) patients had clinical follow-up (median time 7.5 months) and 125 (83.9%) had radiographic follow-up (median time 5 months) information. There were 2 recurrent strokes in the NOAC group and 1 in each of the AC and AP groups (p = 0.822). There were more major hemorrhagic events in the AC group (11.4%) compared to the NOAC (0.0%) and AP (2.5%) groups (p = 0.034). Three patients treated with NOAC and none treated with AC or AP had a worsened degree of stenosis on follow-up imaging (8.6 vs. 0.0 vs. 0.0%, p = 0.019). CONCLUSION: Compared to traditional anticoagulants for CAD, treatment with NOACs is associated with similar rates of recurrent stroke, fewer hemorrhagic complications, but greater rates of radiographic worsening. These data suggest that NOACs may be a reasonable alternative in the management of CAD. Prospective validation of these findings is needed.

Radiofrequency ablation of a solitary liver metastasis complicated by colonic perforation.

Radiofrequency ablation is used for the treatment of primary liver malignancies and liver metastases. In this case, the authors performed percutaneous radiofrequency ablation of a solitary esophageal carcinoma metastasis within the left hepatic lobe. Following the procedure, the patient developed a colonic perforation with a large right upper quadrant abscess. Although the abscess nearly resolved after intravenous antibiotics and percutaneous drainage, the patient ultimately developed a colocutaneous fistula that required surgical excision and right hemicolectomy. The risks for developing this complication as well as measures to minimize this risk are discussed.

Examination of selected clinical factors and medication use as risk factors for pneumonia during stroke rehabilitation: a case-control study.

OBJECTIVE: To assess the association of selected clinical factors and specific medication use (proton pump inhibitors, H2 receptor antagonists [H2 blockers], and angiotensin-converting enzyme inhibitors) with presence of pneumonia in patients with stroke undergoing acute inpatient rehabilitation. DESIGN: Matched case-control study in a freestanding urban academic inpatient acute rehabilitation hospital. Participants were 72 stroke survivors, consisting of 36 patients who developed pneumonia during rehabilitation hospitalization individually matched in order of decreasing priority on age, sex, stroke side, depth, and severity with 36 patients with stroke not developing pneumonia. Potential risk factors, including severe dysphagia, dietary interventions, presence of tracheostomy or feeding tube, and specific medications, were assessed for association with pneumonia during rehabilitation using separate univariate and multivariate analyses. Functional change was assessed using the functional independence measure. RESULTS: Although pneumonia was associated with proton pump inhibitors or H2 blockers (odds ratio, 3.3; 95% confidence interval, 1.0-13.7), any feeding tube (odds ratio: 5.0; 95% confidence interval, 1.4-27.0), severe dysphagia (odds ratio: 15.0; 95% confidence interval, 2.3-631), and tracheostomy (odds ratio: 10; 95% confidence interval, 1.4-434.0) on univariate evaluation, none of these individual factors was significantly associated with pneumonia in a multivariate model. Risk factors were found to be highly related to each other. Odds of pneumonia did not significantly decrease with angiotensin-converting enzyme inhibitors (odds ratio: 0.9; 95% confidence interval, 0.2-3.0). Patients with pneumonia had a significantly lower functional independence measure score at discharge. CONCLUSIONS: A reduction in pneumonia was not found with the use of angiotensin-converting enzyme inhibitors. Although tracheostomies, feeding tubes, proton pump inhibitor or H2 blocker use, and the presence of dysphagia were identified as risk factors for pneumonia on univariate analyses, none of these factors demonstrated an independent association with pneumonia on multivariate analyses. It may be more that the underlying impairment, rather than the assessed interventions, may confer greater risk of pneumonia in the poststroke patient.

Mating behavior is controlled by acute changes in metabolic fuels.

Mild food restriction for 48 h inhibits mating behavior in female musk shrews (Suncus murinus). However, mating behavior is restored after a 90-min feeding bout. In this series of experiments, we examined the role of metabolic fuels in this behavioral restoration. First, drugs reported to block glycolysis or fatty acid oxidation were given 2 h before mating. Both treatments inhibited mating in food-restricted females that were refed after treatment. Blood glucose levels were assessed in females that were fed ad libitum, food restricted, or food restricted and refed for 90 min. Food restriction significantly lowered blood glucose compared with ad libitum feeding or food restriction in combination with 90 min of refeeding. However, neither glucose nor fat alone could substitute for food and promote mating behavior in food-restricted females. In addition, analysis of ketone bodies and body composition in females demonstrated low or undetectable levels of these energy substrates. Our data suggest that musk shrews have relatively little stored energy. Therefore, female musk shrews rely on continuous food intake and monitor multiple cues acutely, including glucose availability and fatty acid oxidation. This ensures that mating does not occur when adequate energy is unavailable.