This comprehensive review details the understanding of the anatomy and physiology of the intestinal lymphatic system in health and disease, with a focus on aspects relevant to drug delivery. It highlights current state-of-the-art approaches to deliver drugs to the intestinal lymphatics and the shift toward the use of these strategies to achieve pharmacokinetic and therapeutic benefits for patients.

Somatostatin and somatostatin-expressing neurons in the brain are extensively involved in cognition. Loss of somatostatin and somatostatin-expressing neurons in Alzheimer disease rests at the center of a series of interdependent pathological events contributing to cognitive decline and dementia. Targeting somatostatin-mediated processes has significant therapeutic potential for the treatment of Alzheimer disease.

α-Synuclein is a key pathogenic protein in Parkinson’s disease and other synucleinopathies, making it a leading therapeutic target for disease modification. Multiple posttranslational modifications occur at various sites in α-Synuclein and alter its biophysical and pathological properties, some interacting with one another to add to the complexity of the pathogenicity of this protein. This review details these modifications, their implications in disease, and potential therapeutic opportunities.

Bile acids facilitate biliary cholesterol solubilization and dietary lipid absorption, regulate host metabolism and immunity, and modulate gut microbiome. Targeting bile acid metabolism and signaling holds promise for treating metabolic and inflammatory diseases.

Combining drugs with different mechanisms of action for synergistic interactions optimizes treatment efficacy and safety. Accurate interpretation of synergy requires the identification of the expected additive effect. Despite innovative models to predict the additive effect, consensus in drug-drug interactions research is lacking, hindering the bench-to-bedside development of combination therapies. Collaboration among science, industry, and regulation is crucial for advancing combination therapy development, ensuring rigorous application of predictive models in clinical settings.

Understanding the complex MS immune pathogenesis provided multiple targets for therapeutic intervention, resulting in a plethora of agents, with various mechanisms of action, efficacy, and safety profiles. However, promoting repair beyond the body’s limited spontaneous extent is still a major challenge. GA, one of the first approved disease-modifying therapies, induces diverse immunomodulatory effects. Furthermore, GA treatment results in elevated neurotrophic factors secretion, remyelination and neurogenesis, supporting the notion that immunomodulatory treatment can support in situ a growth-promoting and repair environment.

Cytochrome P450 enzymes are the major catalysts involved in drug metabolism. The characterization of their individual roles has major implications in drug development and clinical practice.

Pharmacological research at Karolinska Institutet has a long and successful history. Given the 75-year anniversary of the Department of Physiology and Pharmacology, this perspective provides an overview of recent departmental achievements and future trajectories. For these developments, interdisciplinary and intersectoral collaborations and a clear focus on result translation are key elements to continue its legacy of world-leading pharmacological research.

After four decades of intensive research, questions persist about the transduction and control of nitric oxide (NO) synthase bioactivity. Here we discuss NO signaling in cardiovascular health and disease, highlighting new findings, such as the important role of red blood cells in cardiovascular NO homeostasis. Nonclassical signaling modes, like the nitrate-nitrite-NO pathway, and therapeutic opportunities related to the NO system are discussed. Existing and potential pharmacological treatments/strategies, as well as dietary components influencing NO generation and signaling are covered.

The recent years of research have brought about substantial functional and structural insight into mechanisms of activation of Frizzleds and Smoothened. While the advance furthers our mechanistic understanding of ligand recognition, receptor activation, signal specification, and initiation, broader opportunities emerge that allow targeting class F GPCRs for therapy and regenerative medicine employing both biologics and small molecule compounds.

Studies have implicated the kynurenine pathway of tryptophan in the pathophysiology of neurologic and psychiatric diseases. Key enzymes of the kynurenine pathway regulate brain metabolism in both health and disease, making them promising targets for treating these disorders. Therefore, understanding the distribution, cellular expression, and regulation of these enzymes and metabolites in the brain is critical for developing effective therapeutic strategies. This review endeavors to describe these processes in detail.:

Newly diagnosed patients with optic neuritis referred to a tertiary academic MS center from July 2022 to January 2024 underwent both point-of-care pMRI and subsequent 3T conventional MRI (cMRI). Images were evaluated for periventricular (PV), juxtacortical (JC), and infratentorial (IT) lesions. DIS was determined on brain MRI per 2017 McDonald criteria. Test characteristics were computed by using cMRI as the reference. Interrater and intermodality agreement between pMRI and cMRI were evaluated by using the Cohen . Time from symptom onset to pMRI and cMRI during the study period was compared with the preceding 1.5 years before pMRI implementation by using Kruskal-Wallis with post hoc Dunn tests.

Twenty patients (median age: 32.5 years [interquartile range {IQR}, 28–40]; 80% women) were included, of whom 9 (45%) and 5 (25%) had DIS on cMRI and pMRI, respectively. Median time interval between pMRI and cMRI was 7 days (IQR, 3.5–12.5). Interrater agreement was very good for PV (95%, = 0.89), and good for JC and IT lesions (90%, = 0.69 for both). Intermodality agreement was good for PV (90%, = 0.80) and JC (85%, = 0.63), and moderate for IT lesions (75%, = 0.42) and DIS (80%, = 0.58). pMRI had a sensitivity of 56% and specificity of 100% for DIS. The median time from symptom onset to pMRI was significantly shorter (8.5 days [IQR 7–12]) compared with the interval to cMRI before pMRI deployment (21 days [IQR 8–49], n = 50) and after pMRI deployment (15 days [IQR 12–29], n = 30) (both P < .01). Time from symptom onset to cMRI in those periods was not significantly different (P = .29).

In patients with optic neuritis, pMRI exhibited moderate concordance, moderate sensitivity, and high specificity for DIS compared with cMRI. Its integration into the MS clinic reduced the time from symptom onset to MRI. Further studies are warranted to evaluate the role of pMRI in expediting early MS diagnosis and as an imaging tool in resource-limited settings.

One hundred patients who underwent 7T neuroimaging between October 27, 2021, and August 10, 2023, were included. Each case was evaluated for cleftlike pituitary hypointensity, pituitary masses, and artifacts on contrast-enhanced 3D fat-saturated T1 MPRAGE. Follow-up examinations were evaluated if present. The average prevalence for each finding was calculated, as were descriptive statistics for age and sex.

A cleftlike hypointensity was present in 66% of 7T MRIs. There were no significant differences between the "cleftlike present" and "cleftlike absent" groups regarding sex (P = .39) and age (P = .32). The cleftlike hypointensity was demonstrated on follow-up MRIs in 3/3 patients with 7T, 1/12 with 3T, and 1/5 with 1.5T. A mass was found in 22%, while 75% had no mass and 3% were indeterminate. A mass was found in 18 (27%) of the cleftlike present and 4 (13%) of the cleftlike absent groups. The most common mass types were Rathke cleft cyst in 7 (31.8%) patients, "Rathke cleft cyst versus entrapped CSF" in 6 (27.3%), and microadenoma in 6 (22.2%) in the cleftlike present group. There were no significant differences in the mass types between the cleftlike present and cleftlike absent groups (P = .23). Susceptibility and/or motion artifacts were frequent using contrast-enhanced 3D fat-saturated T1 MPRAGE (54%). Artifact-free scans were significantly more frequent in the cleftlike present group (P = .03).

A cleftlike nonenhancing hypointensity was frequently seen on the contrast-enhanced 3D fat-saturated T1 MPRAGE images at 7T MRI, which most likely represents a normal embryologic Rathke cleft remnant and cannot be seen in lower-field-strength MRIs. Susceptibility and motion artifacts are common in the sella. They may affect image quality, and the artifacts at 7T may lead to an underestimation of the prevalence of the Rathke cleft and other incidental findings.

Clinical and radiologic data of our original cohort of patients were retrospectively collected and reviewed to provide an extended follow-up assessment. The need for revision spinal surgery was assessed as the primary outcome, and the radiologic stability of the augmented spinal implants was considered as the secondary outcome.

An extended radiologic follow-up was available in 27/29 patients with an average of 50.9 months. Overall, 18 of 27 (66.7%) patients, originally candidates for revision surgery, avoided a surgical intervention after a cement augmentation rescue procedure. In the remaining patients, the average interval between the rescue cement augmentation and the revision surgery was 22.5 months. Implant mobilization occurred in 2/27 (7.4%) patients; rod breakage, in 1/27 (3.7%); a new fracture within or adjacent to the instrumented segment occurred in 4/27 (14.8%) patients; and screw loosening at rescued levels occurred in 5/27 (18.5%) patients.

In this cohort, cement augmentation rescue procedures were found to be effective in avoiding or postponing revision surgery during long-term follow-up.

Nineteen (14 female, 5 male) patients with CLN2 disease at 1 UK center were studied using serial 3D T1-weighted MRI (follow-up time, 1–9 years). Brain segmentation was performed using FreeSurfer. Volume measurements for supratentorial gray and white matter, deep gray matter (basal ganglia/thalami), the lateral ventricles, and cerebellar gray and white matter were recorded. The volume change with time was analyzed using a linear mixed-effects model excluding scans before treatment onset. Comparison was made with a published natural history cohort of 12 patients (8 female, 4 male), which was re-analyzed using the same method.

Brain volume loss of all segmented brain regions was much slower in treated patients compared with the natural history cohort. For example, supratentorial gray matter volume in treated patients decreased by a mean of 3% (SD, 0.74%) (P < .001) annually compared with an annual volume loss of a mean of 16.8% (SD, 1.5%) (P < .001) in the natural history cohort.

Our treatment cohort showed a significantly slower rate of brain parenchymal volume loss compared with a natural history cohort in several anatomic regions. Our results complement prior clinical data that found a positive response to ERT. We demonstrate that automated MRI volumetry is a sensitive tool to monitor treatment response in children with CLN2 disease.

In this retrospective comparative observational study, we only included pathology-proved cases of hemangioblastoma, while the control group consisted of other randomly selected pathology-proved posterior fossa tumors from January 2022 to January 2024. Two blinded neuroradiologists analyzed all applicable MRI sequences, including ASL sequence if available. ASL was analyzed for the lightbulb sign. Disagreements between the radiologists were resolved by a third pediatric neuroradiologist. ² and Fisher exact test were used to analyze the data.

Ninety-five patients were enrolled in the study; 57 (60%) were boys. The median age at diagnosis was 8 years old (interquartile range: 3–14). Of the enrolled patients, 8 had hemangioblastoma, and 87 had other posterior fossa tumors, including medulloblastoma (n = 31), pilocytic astrocytoma (n = 23), posterior fossa ependymoma type A (n = 16), and other tumors (n = 17). The comparison of hemangioblastoma versus nonhemangioblastoma showed that peripheral edema (P = .02) and T2-flow void (P = .02) favor hemangioblastoma, whereas reduced diffusion (low ADC) (P = .002) and ventricular system extension (P = .001) favor nonhemangioblastoma tumors. Forty-two cases also had ASL perfusion sequences. While high perfusion favors hemangioblastoma (P = .03), the lightbulb sign shows a complete distinction because all the ASL series of hemangioblastoma cases (n = 4) showed the lightbulb sign, whereas none of the nonhemangioblastoma cases (n = 38) showed the sign (P < .001).

Lightbulb-like intense and homogeneous hyperperfusion patterns on ASL are helpful in diagnosing posterior fossa hemangioblastoma in children.

This retrospective study included children with histologically confirmed diagnoses of intracranial epidermoids, temporal bone cholesteatomas, or head and neck epidermal inclusion cysts. Lesions were segmented, and voxelwise calculation of ADC values was performed along with histogram analysis. ADC calculations were validated with a second analysis software to ensure accuracy. Normal brain ROIs—including the cerebellum, white matter, and thalamus—served as normal comparators. Correlational analysis and Bland-Altman plots assessed agreement among software tools for ADC calculations. Differences in the distribution of values between the lesions and normal brain tissues were assessed using the Wilcoxon rank sum and Kruskal-Wallis tests.

Forty-eight pathology-proved cases were included in this study. Among them, 13 (27.1%) patients had intracranial epidermoids 14 (29.2%) had head and neck epidermal inclusion cysts, and 21 (43.7%) had temporal bone cholesteatomas. The mean age was 8.67 (SD, 5.30) years, and 27 (56.3%) were female. The intraclass correlation for absolute agreement for lesional ADC between the 2 software tools was 0.997 (95% CI, 0.995–0.998). The intracranial epidermoid head and neck epidermal inclusion cyst, and temporal bone cholesteatoma median ADC values were not significantly different (973.7 versus 875.7 versus 933.2 x 10^–6 mm²/s, P = .265). However, the ADCs of the 3 types of lesions were higher than those of 3 normal brain tissue types (933 versus 766, x 10^–6 mm²/s, P < .001).

The ADC values of intracranial epidermoids, temporal bone cholesteatomas, and head and neck epidermal inclusion cysts are higher than those of normal brain regions. It is not accurate to simply classify these lesions as exhibiting restricted diffusion or reduced diffusivity without considering the tissue used for comparison. The observed hyperintensity on DWI compared with the brain is likely attributable to a relatively higher contribution of the T2 shinethrough effect.

A single-center observational cohort study was performed. All patients with histologically confirmed WHO grade 2 and 3 gliomas managed with surgical debulking between January 2015 and December 2020 were identified. Preoperative, early postoperative, and follow-up imaging were reviewed independently by 2 consultant neuroradiologists. The extent of resection was estimated with and without DWI sequences for each case.

Two hundred twenty-four patients with WHO grade 2 and 3 gliomas were managed with surgical debulking between 2015 and 2020. DWI was not performed on early postoperative MRI in 2 patients. With the use of DWI, the extent of resection was upgraded in 30% of cases (n = 66/222) and classified as "complete" or "supramaximal" in 58% of these patients (n = 38/66). In cases in which the extent of resection was upgraded with the use of DWI, signal abnormality was stable or reduced at follow-up in 78% (n = 49/63). In cases with worsening signal abnormality, 64% were deemed to be secondary to adjuvant radiation therapy (n = 9/14). Eight percent (n = 5/63) of patients with an increased estimated extent of resection using DWI demonstrated signal progression attributed to true disease progression at follow-up.

DWI is a helpful and reliable adjunct in differentiating residual tumor from marginal ischemia in early postoperative MRI in WHO grade 2 and 3 diffuse gliomas and increases the accuracy in assessing the extent of resection. It should be used routinely in these cases.

One hundred eight patients with presumed or confirmed meningiomas who underwent a brain MRI at multiple doses of gadolinium were included in the study. The patients’ MRIs were categorized into 3 groups based on the gadolinium dose administered: micro (approximately 25% of the standard dose), low (approximately 62% of the standard dose), and standard dose. Multireader qualitative visual assessment and quantitative relative signal differences calculations were performed to evaluate tumor differentiation from the cortex and from the dural venous sinus. The relative signal differences for each dose were analyzed by using ANOVA for quantitative assessment and the McNemar test for qualitative assessment. Additionally, noninferiority testing was used to compare the low and micro doses to the standard dose.

Decreasing the gadolinium dose to a low dose or micro dose resulted in a statistically significant decrease in signal difference between the tumor and the adjacent brain tissue (P < .02). However, on visual assessment, the low dose was noninferior to the standard dose. The proportion of cases with suboptimal differentiation was significantly higher for the micro dose than for the standard dose, both for the differentiation between the tumor and the cortex (P = .041) and the differentiation between the tumor and the sinus (P < .001).

Reducing the gadolinium dose to 62% of the standard level still allows for sufficient visual delineation of meningiomas from surrounding tissues. However, further reduction to 25% substantially compromises the ability to distinguish the tumor from adjacent structures and is, therefore, not advisable.

Ninety-four patients (52 ± 22 years old, 69 women, 25 men) diagnosed with meningioma were recruited in the study. Each patient underwent preoperative T1WI, T2WI, DTI, and MR elastography. Combined MR elastography–DTI model was developed based on multiple logistic regression. Intraoperative tumor descriptions served as clinical criteria for evaluating meningioma consistency. The diagnostic efficacy in determining meningioma consistency was evaluated by using a receiver operating characteristic curve. Further validation was conducted in 27 stereotactic biopsies by using indentation tests and underlying mechanism was investigated by histologic analysis.

Among all the imaging modalities, MR elastography demonstrated the highest efficacy with the shear modulus magnitude (|G*|) achieving an area under the curve (AUC) of 0.81 (95% CI: 0.699–0.929). When combined with DTI, the diagnostic accuracy further increased (AUC: 0.88, 95% CI: 0.784–0.971), surpassing any technique alone. Indentation measurement based on stereotactic biopsies further demonstrated that the MR elastography–DTI model was suitable for predicting intratumor consistency. Histologic analysis suggested that meningioma consistency may be correlated with tumor cell density and fibrous content.

The MR elastography–DTI combined model is effective in noninvasive prediction of meningioma consistency.

The study enrolled 28 patients with WD (19 with neurologic symptoms) and 25 controls. Fractional anisotropy (FA), mean diffusivity (MD), and magnetic susceptibility in globus pallidus, pontine tegmentum, dentate nucleus, red nucleus, head of caudate nucleus, putamen, substantia nigra, and thalamus were extracted. Correlations between imaging data and the Unified Wilson’s Disease Rating Scale (UWDRS) neurologic subitems were explored.

FA, MD, and susceptibility values were higher in multiple DGN of patients with WD than controls (P < .05). Patients with WD without abnormal signals in DGN on routine MRI also had higher FA, MD, and susceptibility values than controls (P < .017). We found that UWDRS neurologic subscores correlated with FA and susceptibility values of DGN (P < .05). In addition, we also found that FA and susceptibility values in specific structures correlated with specific neurologic symptoms of WD (ie, tremor, parkinsonism, dysarthria, dystonia, and ataxia) (P < .05).

Patients with WD have increased FA, MD, and susceptibility values even before the lesion is morphologically apparent on routine MRI. The increased FA and susceptibility values correlate with clinical severity of WD.

Twenty-two patients with AD, 17 with FTD, and 21 cognitively healthy patients were identified from the electronic health systems record and a behavioral neurology clinic. Four neuroradiologists evaluated T1-weighted anatomic MRI studies with and without a volumetric report. Outcome measures were the proportion of correct diagnoses of neurodegenerative disease versus normal aging ("rough accuracy") and AD versus FTD ("exact accuracy"). Generalized linear mixed models were fit to assess whether the use of a volumetric report was associated with higher accuracy, accounting for random effects of within-rater and within-subject variability. Post hoc within-group analysis was performed with multiple comparisons correction. Residualized volumes were tested for an association with the diagnosis using ANOVA.

There was no statistically significant effect of the report on overall correct diagnoses. The proportion of "exact" correct diagnoses was higher with the report versus without the report for AD (0.52 versus 0.38) and FTD (0.49 versus 0.32) and lower for cognitively healthy (0.75 versus 0.89). The proportion of "rough" correct diagnoses of neurodegenerative disease was higher with the report than without the report within the AD group (0.59 versus 0.41), and it was similar within the FTD group (0.66 versus 0.63). Post hoc within-group analysis suggested that the report increased the accuracy in AD (OR = 2.77) and decreased the accuracy in cognitively healthy (OR = 0.25). Residualized hippocampal volumes were smaller in AD (mean difference –1.8; multiple comparisons correction, –2.8 to –0.8; P < .001) and FTD (mean difference –1.2; multiple comparisons correction, –2.2 to –0.1; P = .02) compared with cognitively healthy.

The availability of a brain volumetric report did not improve neuroradiologists’ accuracy over visual assessment in diagnosing AD or FTD in this limited sample. Post hoc analysis suggested that the report may have biased readers incorrectly toward a diagnosis of neurodegeneration in cognitively healthy adults.

We identified inpatients or patients in the emergency department who underwent CTAHN (including noncontrast and postcontrast head CT, with or without CTP imaging) followed within 24 hours by a 3T MRI study that included a 2.5-minute unenhanced multicontrast sequence (NeuroMix) and a 5-minute intracranial time of flight MRA) during a 9-month period (April to December 2022). Cases were classified by 4 radiologists in consensus as to whether NeuroMix and NeuroMix + MRA detected equivalent findings, detected unique findings, or missed findings relative to CTAHN.

One hundred seventy-four cases (mean age, 67 [SD, 16] years; 56% female) met the inclusion criteria. NeuroMix alone and NeuroMix + MRA protocols were determined to be equivalent or better compared with CTAHN in 71% and 95% of patients, respectively. NeuroMix always provided equivalent or better assessment of the brain parenchyma, with unique findings on NeuroMix and NeuroMix + MRA in 35% and 36% of cases, respectively, most commonly acute infarction or multiple microhemorrhages. In 8/174 cases (5%), CTAHN identified vascular abnormalities not seen on the NeuroMix + MRA protocol due to the wider coverage of the cervical arteries by CTAHN.

A fast MR imaging protocol consisting of NeuroMix + MRA provided equivalent or better information compared with CTAHN in 95% of cases in our population of patients with an acute neurologic presentation. The findings provide a deeper understanding of the benefits and challenges of a fast unenhanced MR-first approach with NeuroMix + MRA, which could be used to design prospective trials in select patient groups, with the potential to reduce radiation dose, mitigate adverse contrast-related patient and environmental effects, and lessen the burden on radiologists and health care systems.

The institutional review board approved this retrospective study of cervical spine CT emergency department results from 2 hospitals in our health system after reviewing 5 years of data in patients experiencing trauma. In addition to the primary variable of age (younger than 65 years and 65 years and older), we looked at injury mechanism, fracture types, sites, symptoms, and operative or medical treatments. Because the demographics of our home site is different from most towns in the United States, we provide race/ethnicity data.

Of 21,986 cervical spine CTs, 190/9455 (2.0%) participants 65 years of age and older and 199/12,531 (1.6%) participants younger than 65 years of age had fractures (total, 389/21,986, 1.8%). There were more cases of falls from standing (106, 55.8%) and falls from a height (46, 4.2%) in those 65 years and older and this mechanism was associated with a higher risk of C1 and C2 fractures (52, 27.4%; and 78, 41.1%, respectively). Among the C1 fractures, anterior and posterior arch fractures predominated (37, 19.5%). For C2 fractures, types 2 and 3 odontoid fractures (39, 20.5%; and 12, 6.3%) were more common in the older cohort. Motor vehicle collisions were more common in the younger cohort (89, 44.7%), and they were associated with more C5–C7 fractures (47, 23.6%; 60, 30.2%; and 66, 33.2%, respectively) including the facets (49, 24.6%), spinous processes (31, 15.6%), and transverse processes (52, 26.1%). Overall, the rates of instability, surgical intervention, and asymptomatic fractures were similar in the 2 age groups.

Cervical spine fractures appear in about 1.8% of the CT scans performed in a busy emergency department environment. Fractures in the elderly occur more commonly due to falls, are located at C1 and C2, and may involve ligamentous injuries. Younger patients incur trauma more commonly due to motor vehicle collisions, and they are more likely to affect the posterior elements, especially C5–C7. The differences in trends for fractures in the 65 years of age and older and younger than 65 years of age groups have persisted since the Canadian C-Spine Rule 1996–1998 data were collected.

We retrospectively analyzed patients with symptomatic intracranial atherosclerotic stenosis stent placement in a prospective cohort at a high-volume stroke center. Clinical, radiologic, and periprocedural characteristics and long-term outcomes were reviewed. Periprocedural intracranial hemorrhage was classified as procedure-related hemorrhage (PRH) and non-procedure-related hemorrhage (NPRH). The long-term outcomes were compared between patients with PRH and NPRH, and the predictors of NPRH were explored.

Among 1849 patients, 24 (1.3%) had periprocedural intracranial hemorrhage, including PRH (4) and NPRH (20). The postprocedural 30-day mRS was 0–2 in 9 (37.5%) cases, 3–5 in 5 (20.8%) cases, and 6 in 10 (41.7%) cases. For the 14 survivors, the long-term (median of 78 months) mRS were 0–2 in 10 (76.9%) cases and 3–5 in 3 (23.1%) cases. The proportion of poor long-term outcomes (mRS ≥3) in patients with NPRH was significantly higher than those with PRH (68.4% versus 0%, P = .024). Anterior circulation (P = .002), high preprocedural stenosis rate (P < .001), and cerebral infarction within 30 days (P = .006) were independent predictors of NPRH after stent placement.

Patients with NPRH had worse outcomes than those with PRH after stent placement for symptomatic ICAS. Anterior circulation, severe preprocedural stenosis, and recent infarction are independent predictors of NPRH.

StA setup consisted of an aspiration pump connected to pressure transducer. CyA was tested with 5 subsequent iterations: single solenoid valve with air plus saline (i1) or saline alone (i2) as aspiration medium; 2 solenoid valves with air plus saline (i3) as aspiration medium; complete air removal and saline feeding (i4); and pressurized saline feeding (i5). To assess the efficacy of clot ingestion, the pressure transducer was replaced with a distal aspiration catheter. Moderately stiff clot analogs (15 mm) were used to investigate the ingestion quantified as clot relative weight loss. Additionally, the aspiration flow rate was assessed for each setup.

With CyA i1, the amplitude of the achieved negative pressure waves declined with increasing frequencies but progressively increased with each subsequent iteration, achieving a maximum amplitude of 81 kPa for i5 at 1 Hz. Relative clot weight loss was significantly higher with i5 at 5 Hz than with StA (100% versus 37.8%; P = .05). Aspiration flow rate was lower with CyA than with StA (i5 at 5 Hz: 199.8 mL/min versus StA: 311 mL/min; P < .01).

CyA with the appropriate setup may represent an encouraging innovation in mechanical thrombectomy, offering a promising pathway for improving efficacy in clot ingestion and recanalization. The observed benefits warrant confirmation in a clinical setting.

Patients from 2 comprehensive stroke centers were reviewed (2020–2023). We included patients with failed thrombectomy and/or underlying intracranial stenosis who received SAIL with tirofiban before the intended angioplasty and stent placement. SAIL consisted of deploying a stent retriever through the occluding lesion to create a bypass channel and infuse 10 mL of tirofiban for 10 minutes either intra-arterially or IV. The stent retriever was re-sheathed before retrieval. The primary end points were successful reperfusion (expanded TICI 2b–3) and symptomatic intracerebral hemorrhage. Additional end points included 90-day mRS 0–2 and mortality.

After a median of 3 (interquartile range, 2–4) passes, 44 patients received the SAIL bridging protocol with tirofiban, and later they were considered potential candidates for angioplasty and stent placement bailout (43.2%, intra-arterial SAIL). Post-SAIL successful reperfusion was obtained in 79.5%. A notable residual stenosis (>50%) after successful SAIL was observed in 45.7%. No significant differences were detected according to post-SAIL: successful reperfusion (intra-arterial SAIL, 80.0% versus IV-SAIL, 78.9%; P = .932), significant stenosis (33.3% versus 55.0%; P = .203), early symptomatic re-occlusion (0% versus 8.0%; P = .207), or symptomatic intracerebral hemorrhage (5.3% versus 8.0%; P = .721). Rescue angioplasty and stent placement were finally performed in 15 (34.1%) patients (intra-arterial SAIL 21.0% versus IV-SAIL 44%; P = .112). At 90 days, mRS 0–2 (intra-arterial SAIL 50.0% versus IV-SAIL 43.5%; P = .086) and mortality (26.3% versus 12.0%; P = .223) were also similar.

In patients with stroke in which angioplasty and stent placement are considered, SAIL with tirofiban, either intra-arterial or IV, seems to safely induce sustained recanalization, offering a potential alternative to definitive angioplasty and stent placement.

We conducted a historical, multicenter registry study at 51 centers that enrolled patients with AT-LVO. We divided the patients into 3 groups based on the endovascular therapy technique: mechanical thrombectomy alone, percutaneous transluminal angioplasty (PTA), and stent deployment. Mechanical thrombectomy alone was classified into the mechanical thrombectomy-only group; PTA and mechanical thrombectomy–PTA, into the PTA group; and mechanical thrombectomy–stent deployment, mechanical thrombectomy–PTA–stent deployment, PTA–stent deployment, and stent deployment–only into the stent group. The primary outcome was incidence of reocclusion of the treated vessels within 90 days of endovascular therapy completion.

We enrolled 770 patients and analyzed 509 patients. The rates in the mechanical thrombectomy-only, PTA, and stent deployment groups were 40.7%, 44.4%, and 14.9%, respectively. Incidence rate of residual stenosis >70% of final angiography was significantly higher in the mechanical thrombectomy-only group than in the PTA and stent deployment groups (mechanical thrombectomy-only versus PTA versus stent deployment: 34.5% versus 26.3% versus 13.2%, P = .002). Reocclusion rate was significantly lower in the PTA group than in the mechanical thrombectomy-only group (adjusted hazard ratio, 0.48; 95% CI, 0.29–0.80). Of the patients, 83.5% experienced reocclusion within 10 days after endovascular therapy. Alarmingly, a substantial subset (approximately 62.0%) of patients experienced reocclusion within 2 days of endovascular therapy. Incidence of mRS scores of 0–2 ninety days after endovascular therapy was not significantly different among the 3 groups. Incidences of symptomatic intracranial hemorrhage, any other intracranial hemorrhage, and death were not significantly different.

Incidence rate of reocclusion was significantly lower in the PTA group than in the mechanical thrombectomy-only group. We found no meaningful difference in reocclusion rates between the stent deployment and mechanical thrombectomy-only groups. In Japan, glycoprotein IIb/IIIa inhibitors are not reimbursed. Therefore, PTA might be the preferred choice for AT-LVOs due to the higher reocclusion risk with mechanical thrombectomy-only. Reocclusion was likely to occur within 10 days, particularly within 2 days post-endovascular therapy.

This study was single-center retrospective cohort study, and we obtained medical records of patients who underwent VBS. We compared clinical and periprocedural factors between extracranial and intracranial VBS. The primary outcomes included the incidence of in-stent restenosis (>50% reduction in lumen diameter) and stented-territory ischemic events. We compared the incidence of in-stent restenosis and stented-territory ischemic events by using Kaplan-Meier curves.

Of the 105 patients, 41 (39.0%) underwent extracranial VBS, and 64 (61.0%) underwent intracranial VBS. During the follow-up, the incidences of in-stent restenosis and stented-territory ischemic events were 15.2% and 22.9%, respectively. The procedure time was longer (47.7 ± 19.5 minutes versus 74.5 ± 35.2 minutes, P < .001), and the rate of residual stenosis (≥30%) just after VBS was higher (2 [4.9%] versus 24 [37.5%], P < .001) in intracranial VBS than in extracranial VBS. Also, the incidences of in-stent restenosis were significantly higher in intracranial VBS than in extracranial VBS (4.9% versus 21.9%, P = .037). On the other hand, the incidences of stented-territory ischemic events (7.3% versus 32.8%, P < .001) were significantly higher in intracranial VBS than in extracranial VBS. The main mechanisms of stroke were artery-to-artery embolism (2 [66.7%]) in extracranial VBS, and artery-to-artery embolism (9 [42.9%]) and branch atheromatous disease (8 [38.1%]) in intracranial VBS. The Kaplan-Meier curve demonstrated a higher incidence of in-stent restenosis and stented-territory ischemic events in intracranial VBS than in extracranial VBS (P = .008 and P = .002, respectively).

During the follow-up, the incidence of in-stent restenosis and stented-territory ischemic events was higher in patients with intracranial VBS than in those with extracranial VBS. The higher rates of postprocedural residual stenosis might have contributed to the increased risk of in-stent restenosis. Furthermore, prolonged procedure time and additional stroke mechanism, including branch atheromatous disease, might be associated with a higher risk of stented-territory ischemic events in intracranial VBS.

In 35 patients with 37 unruptured IAs, a 3T MRA and a 7T 4D MRI flow scan were performed. Five hemodynamic parameters—peak-systolic wall shear stress (WSS_MAX) and time-averaged wall shear stress (WSS_MEAN), oscillatory shear index (OSI), mean velocity, and velocity pulsatility index—were correlated to 6 3D morphology proxy parameters of aneurysm instability—major axis length, volume, surface area (all 3 size parameters), flatness, shape index, and curvedness—by Pearson correlation with 95% CI. Scatterplots of hemodynamic parameters that correlated with IA size (major axis length) were created.

WSS_MAX and WSS_MEAN correlated negatively with all 3 size parameters (strongest for WSS_MEAN with volume (r = –0.70, 95% CI –0.83 to –0.49) and OSI positively (strongest with major axis length [r = 0.87, 95% CI 0.76–0.93]). WSS_MAX and WSS_MEAN correlated positively with shape index (r = 0.61, 95% CI 0.36–0.78 and r = 0.49, 95% CI 0.20–0.70, respectively) and OSI negatively (r = –0.82, 95% CI –0.9 to –0.68). WSS_MEAN and mean velocity correlated negatively with flatness (r = –0.35, 95% CI –0.61 to –0.029 and r = –0.33, 95% CI –0.59 to 0.007, respectively) and OSI positively (r = 0.54, 95% CI 0.26–0.74). Velocity pulsatility index did not show any statistically relevant correlation.

Out of the 5 included hemodynamic parameters, WSS_MAX, WSS_MEAN, and OSI showed the strongest correlation with morphologic 3D proxy parameters of aneurysm instability. Future studies should assess these promising new imaging marker parameters for predicting aneurysm instability in longitudinal cohorts of patients with IA.

Brain MRIs of 53 subjects with FD (mean age, 40.7 [SD, 12.4] years; male/female ratio = 23:30) were collected in this single-center study. Mean BA diameter and its tortuosity index were calculated on MRA. Possible correlations between these metrics and clinical, laboratory, and advanced imaging variables of the posterior circulation were tested. In a subgroup of 20 subjects, a 2-year clinical and imaging follow-up was available, and possible longitudinal changes of these metrics and their ability to predict clinical scores were also probed.

No significant association was found between MRA metrics and any clinical, laboratory, or advanced imaging variable (P values ranging from –0.006 to 0.32). At the follow-up examination, no changes were observed with time for the mean BA diameter (P = .84) and the tortuosity index (P = .70). Finally, baseline MRA variables failed to predict the clinical status of patients with FD at follow-up (P = .42 and 0.66, respectively).

Alterations of the BA in FD lack of any meaningful association with clinical, laboratory, or advanced imaging findings collected in this study. Furthermore, this lack of correlation seems constant across time, suggesting stability over time. Taken together, these results suggest that the role of BA dolichoectasia in FD should be reconsidered.

We studied participants from the UK Southall and Brent REvisited study who underwent 3T brain MRI between 2014 and 2018. TOF-MRA images were assessed for the presence of incidental cerebrovascular findings and used to determine CoW anatomy.

Seven hundred fifty participants (mean age, 71.28 [SD, 6.46] years; range, 46–90 years; 337 women), 322 White Europeans, 253 South Asians, and 175 African Caribbeans were included. Incidental cerebrovascular findings were observed in 84 subjects (11.2%, 95% CI, 9.0%–13.7%; 36 women; 42.86%, 95% CI, 32.11%–54.12%), with cerebral aneurysms being the most frequent followed by intracranial arterial stenoses with the highest prevalence among South Asians compared with White European (OR: 2.72; 95% CI, 1.22–6.08; P = .015) and African Caribbean subjects (OR: 2.79; 95% CI, 1.00–7.82; P = .051). Other findings included arteriovenous malformations and infundibula. The CoW was found to be more often complete in women than in men (25.22% compared with 18.41%, P = .024) and in African Caribbean (34.86%) compared with White European (19.19%) and South Asian (14.23%) subjects (P < .001 each).

Intracranial arterial stenoses were independently associated with ethnicity after adjusting for vascular risk factors, having the highest prevalence among South Asians. The prevalence of aneurysms was higher than that in previous population-based studies. We observed anatomic differences in the CoW configuration among women, men, and ethnicities.

Clinical and optimized deep learning–based image reconstruction T1 3D Sampling Perfection with Application optimized Contrast using different flip angle Evolution (SPACE) were evaluated, comparing noncontrast sequences in 10 healthy controls and postcontrast sequences in 5 consecutive patients. Images were reviewed on a Likert-like scale by 4 fellowship-trained neuroradiologists. Scores (range, 1–4) were separately assigned for 11 vessel segments in terms of vessel wall and lumen delineation. Additionally, images were evaluated in terms of overall background noise, image sharpness, and homogeneous CSF signal. Segment-wise scores were compared using paired samples t tests.

The scan time for the clinical and deep learning–based image reconstruction sequences were 7:26 minutes and 5:23 minutes respectively. Deep learning–based image reconstruction images showed consistently higher wall signal and lumen visualization scores, with the differences being statistically significant in most vessel segments on both pre- and postcontrast images. Deep learning–based image reconstruction had lower background noise, higher image sharpness, and uniform CSF signal. Depiction of intracranial pathologies was better or similar on the deep learning–based image reconstruction.

Our preliminary findings suggest that deep learning–based image reconstruction–optimized intracranial vessel wall imaging sequences may be helpful in achieving shorter gradient times with improved vessel wall visualization and overall image quality. These improvements may help with wider adoption of intracranial vessel wall imaging in clinical practice and should be further validated on a larger cohort.

This prospective study was conducted between March 2023 and October 2023. Medical students and resident trainees were asked to identify intracranial hemorrhage and large-vessel occlusion in 100 noncontrast head CTs and 100 head CTAs, respectively. One group received diagnostic aid simulating artificial intelligence for intracranial hemorrhage only (n = 26); the other, for large-vessel occlusion only (n = 28). Primary outcomes included accuracy, sensitivity, and specificity for intracranial hemorrhage/large-vessel occlusion detection without and with aid. Study interpretation time was a secondary outcome. Individual responses were pooled and analyzed with the t test; differences in continuous variables were assessed with ANOVA.

Forty-eight participants completed the study, generating 10,779 intracranial hemorrhage or large-vessel occlusion interpretations. With diagnostic aid, medical student accuracy improved 11.0 points (P < .001) and resident trainee accuracy showed no significant change. Intracranial hemorrhage interpretation time increased with diagnostic aid for both groups (P < .001), while large-vessel occlusion interpretation time decreased for medical students (P < .001). Despite worse performance in the detection of the smallest-versus-largest hemorrhages at baseline, medical students were not more likely to accept a true-positive artificial intelligence result for these more difficult tasks. Both groups were considerably less accurate when disagreeing with the artificial intelligence or when supplied with an incorrect artificial intelligence result.

This study demonstrated greater improvement in diagnostic accuracy with artificial intelligence for medical students compared with resident trainees. However, medical students were less likely than resident trainees to overrule incorrect artificial intelligence interpretations and were less accurate, even with diagnostic aid, than the artificial intelligence was by itself.

Neuroradiologists were identified using a previously-validated method based on Work Relative Value Units and Neiman Imaging Types of Service classification. Data on payments from industry were obtained from the Open Payments database from the Centers for Medicare & Medicaid Services, from 2016 to 2021. Payments were grouped into 7 categories, including consulting fees, education, gifts, medical supplies, research, royalties/ownership, and speaker fees. Descriptive statistics were calculated.

A total of 3019 neuroradiologists were identified in this study. Between 2016 and 2021, 48% (1440/3019) received at least 1 payment from industry, amounting to a total number of 21,967 payments. Each year, among those receiving payments from industry, each unique neuroradiologist received between a mean of 5.49–7.42 payments and a median of 2 payments, indicating a strong rightward skew to the distribution of payments. Gifts were the most frequent payment type made (60%, 13,285/21,967) but accounted for only 4.1% ($689,859/$17,010,546) of payment value. The greatest aggregate payment value came from speaker fees, which made up 36% ($6,127,484/$17,010,546) of the total payment value. The top 5% highest paid neuroradiologists received 42% (9133/21,967) of payments, which accounted for 84% ($14,284,120/$17,010,546) of the total dollar value. Since the start of the coronavirus 2019 (COVID-19) pandemic, the number of neuroradiologists receiving industry payments decreased from a mean of 671 neuroradiologists per year prepandemic (2016–2019) to 411 in the postpandemic (2020–2021) era (P = .030). The total number of payments to neuroradiologists decreased from 4177 per year prepandemic versus 2631 per year postpandemic (P = .011).

Industry payments to neuroradiologists are highly concentrated among top earners, particularly among the top 5% of payment recipients. The number of payments decreased during the COVID-19 pandemic, though the dollar value of payments was offset by coincidental increases in royalty payments. Further investigation is needed in subsequent years to determine if the postpandemic changes in industry payment trends continue.