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The study of artists with acquired brain damage is an empirical way to investigate the multiplicity of cerebral changes that occur with artistic training. We describe a talented painter with a left progressive cerebral lesion. In spite of losing function of her right hand, she regained dexterity of the left one in ten days for painting and drawing but not for writing. We discuss two potential explanations for her rapid recovery: (a) her extensive artistic training and/or (b) the slow-growing nature of her cerebral lesion.

Introduction Neuropsychiatric symptoms (NPS) are both common in mild cognitive impairment and Alzheimer disease (AD). Studies have shown that some NPS such as apathy and depression are a key indicator for progression to AD. Methods We compared Neuropsychiatric Inventory (NPI) total score and NPI subdomain score between mild cognitive impairment-converters (MCI-C) and mild cognitive impairment-nonconverters (MCI-NC) longitudinally for 6 years using the Alzheimer's Disease Neuroimaging Initiative (ADNI) database. In addition to the NPI, Mini-Mental State Examination (MMSE) scores were also compared to find out if MMSE scores would differ between different NPI groups. Lastly, a linear regression model was done on MMSE and NPI total score to establish a relationship between MMSE and NPI total score. Results The results in this study showed that NPI total scores between MCI-C and MCI-NC differed significantly throughout 6 years. MCI-C subjects had a higher mean NPI total score and lower MMSE score compared with MCI-NC subjects. In addition, MMSE scores were significantly different between the 3 groups of NPI total score. Subjects who have a high NPI score have the lowest mean MMSE score, thus demonstrating that NPI scores do indeed affect MMSE scores. Further analyses using a regression model revealed that a unit change in NPI total score lead to 0.1 to 0.3 decrease in MMSE. Discussion On the basis of the findings, this study showed evidence that increase in NPS burden (reflected by increase in NPI) over time predicts conversion to AD, whereas stability of symptoms (reflected by stable NPI score) favors nonconversion. Further study should investigate the underlying mechanisms that drive both NPS burden and cognitive decline.

Little is known about the comparison of multiple-gated acquisition (MUGA) scanning with cardiovascular magnetic resonance (CMR) for serial monitoring of HER2+ breast cancer patients receiving trastuzumab. The association of cardiac biomarkers with CMR left ventricular (LV) function and volume is also not well studied. Our objectives were to compare CMR and MUGA for left ventricular ejection fraction (LVEF) assessment, and to examine the association between changes in brain natriuretic peptide (NT-BNP) and troponin-I and changes in CMR LV function and volume. This prospective longitudinal two-centre cohort study recruited HER2+ breast cancer patients between January 2010 and December 2013. MUGA, CMR, NT-BNP and troponin-I were performed at baseline, 6, 12, and 18 months after trastuzumab initiation. In total, 41 patients (age 51.7 ± 10.8 years) were enrolled. LVEF comparison between MUGA and CMR demonstrated weak agreement (Lin’s correlation coefficient r = 0.46, baseline; r = 0.29, 6 months; r = 0.42, 12 months; r = 0.39, 18 months; all p

BACKGROUND: Delusions affect approximately a third of Alzheimer’s disease(AD) patients and are associated with poor outcomes. Previous studies investigating the neuroanatomical correlates of delusions have yet to reach a consensus, with findings of reduced volume across all the lobes, particularly in frontal regions. The current study examined the grey matter(GM) differences associated with delusions in AD. METHODS: Using voxel-based morphometry(VBM), we assessed GM for 23 AD patients who developed delusions(AD+D) and 36 comparable AD patients who did not develop delusions(AD-D) at baseline and follow up. ANOVA was used to identify consistent differences between AD+D and AD-D patients across both timepoints(main effect of group), consistent changes from baseline to follow up(main effect of time) and differential changes between AD+D and AD-D over time(interaction of group and time). All data were obtained from the NACC database. RESULTS: The AD+D group had consistently lower frontal GM volume, although both groups showed decreased GM in fronto-temporal brain regions over time. An interaction was observed between delusions and longitudinal change, with AD+D patients having significantly elevated GM in predominantly temporal areas at baseline assessment, which had declined to become significantly lower than the AD-D group at follow-up. CONCLUSION: These findings suggest that although individuals with and without delusion show long-term GM decreases, there are specific volumetric markers that distinguish patients with delusion from those without, before and after the onset of delusions. Specifically, the decline of GM in temporal areas that were elevated prior to the onset of delusion may be involved in the manifestation of delusions.

Skilled professional artists are sometimes able to maintain their talents while other cognitive functions deteriorate due to brain diseases. The objective of this study is to asses the preserved artistry of a professional painter in spite of the presence of strokes affecting brain areas implicated in art expression. She had a neurologic evaluation and brain imaging after the stroke; painter-curators analyzed and compared the painter's pictorial artwork created before and after the stroke. In spite of cerebellar, visuospatial, motor, cognitive, and functional deficits likely related to strokes affecting bilateral cerebellar, left occipital, and right temporal-occipital areas, the patient was able to maintain most of their artistic painting skills.. After a short period of functional recovery, our patient showed discrepancy among their impaired cerebellar cerebral functions in day activities and their preserved painting abilities.

Our objectives were to evaluate the temporal changes in CMR-based strain imaging, and examine their relationship with left ventricular ejection fraction (LVEF), in patients treated with trastuzumab.In this prospective longitudinal observational study, 41 women with HER2+ breast cancer treated with chemotherapy underwent serial CMR (baseline, 6, 12, and 18 months) after initiation of trastuzumab (treatment duration 12 months). LVEF and LV strain (global longitudinal[GLS] and circumferential[GCS]) measurements were independently measured by 2 blinded readers.Of the 41 patients, 56% received anthracycline-based chemotherapy. Compared to baseline (60.4%, 95%CI 59.2-61.7%), there was a small but significant reduction in LVEF at 6 months (58.4%, 95%CI 56.7-60.0%, p = 0.034) and 12 months (57.9%, 95%CI 56.4-59.7%, p = 0.012), but not at 18 months (60.2%, 95%CI 58.2-62.2%, p = 0.93). Similarly, compared to baseline, GLS and GCS decreased significantly at 6 months (p = 0.024 and 0.001, respectively) and 12 months (p = 0.002 and 0.001, respectively) with an increase in LV end-diastolic volume, but not at 18 months. There were significant correlations between the temporal (6 month-baseline) changes in LVEF, and all global strain measurements (Pearson's r = -0.60 and r = -0.75 for GLS and GCS, respectively, all p 0.001).There was a significant reduction in LV strain during trastuzumab treatment, which correlated with a concurrent subtle decline in LVEF and was associated with an increase in LV end-diastolic volume. LV strain assessment by CMR may be a promising method to monitor for subclinical myocardial dysfunction in breast cancer patients receiving chemotherapy. Future studies are needed to determine its prognostic and therapeutic implications.

OBJECTIVE The optimal timing of blood pressure (BP) measurement is not firmly established for patients undergoing hemodialysis. We sought to assess which BP measurement change best correlates with changes in left ventricular mass index (LVMI) over 1 year in patients with end-stage renal disease. METHODS Fifty-seven patients were included in a prospective cohort study comparing the cardiovascular impact of conversion to in-center nocturnal hemodialysis versus continuing conventional hemodialysis. BP measurements were recorded at different time points (predialysis, after initiation of dialysis, at the intradialytic nadir, and postdialysis) during dialysis sessions over 12 weeks at baseline and after 1-year follow-up. LVMI was independently measured by a single blinded reader using cardiac magnetic resonance imaging at baseline and 1 year. RESULTS Overall, the mean LVMI was 69.9 g/m (standard deviation 15.9) at baseline and 69.6 g/m (standard deviation 16.0) at 1 year. The change in initiation mean arterial pressure (MAP) most strongly correlated with the change in LVMI (Pearson correlation coefficient r = 0.71, P

Background Neuropsychiatric symptoms (NPS) are common, accelerate the conversion to dementia, and are associated with increased caregiver burden in Alzheimer's disease (AD) and mild cognitive impairment (MCI). Objective The aim of this study is to identify potential associations between the core cerebrospinal fluid (CSF) biomarkers (amyloid/tau) and NPS in AD/MCI. Methods For this systematic review, four databases, PubMed (1946-2018), Cochrane (2005-2018), EMBASE (1947-2018), and PsycINFO (1806-2018) were searched for relevant observational studies using an extensive list of keywords. English studies were selected for critical appraisal based on our inclusion/exclusion criteria. Inclusion criteria were defined as 1) at least one AD CSF biomarker has been measured; 2) at least one NPS has been assessed; and 3) analysis has been done to examine the association between core AD CSF biomarker and NPS (main outcome). Animal, postmortem, and review studies were excluded. Results In total, 21 studies qualified for the systematic review. The overall picture regarding the association between NPS and AD CSF biomarkers is conflicting. However, agitation/aggression was significantly and consistently related to core AD CSF biomarkers. Moreover, depression was the only NPS to occasionally be associated with lower core AD CSF pathology. Conclusion Our study has revealed agitation/aggression as the most consistent NPS related to core AD CSF biomarkers. Future studies are required to focus on other neglected NPS domains such as disinhibition. Moreover, why depression was the only NPS inversely associated with core AD CSF pathology remains to be elucidated. Our study also revealed a great degree of heterogeneity, hence calling for a more standardized "objective" approach for the evaluation of NPS.

Music interventions have been widely adopted as a potential non-pharmacological therapy for patients with Alzheimer's disease (AD) to treat cognitive and/or behavioral symptoms of the disease. In spite of the prevalence of such therapies, evidence for their effectiveness report mixed results in the literature. The purpose of this narrative review is to investigate the effectiveness of various intervention strategies (music therapy vs. music listening techniques) and music type used in the intervention (individualized vs. non-individualized music) on cognitive and behavioral outcomes for persons with AD. Databases were searched for studies using either active music therapy or music listening techniques over the last 10 years. These studies were in English, included persons with AD dementia, and whose protocol gathered pre- and post-intervention outcome measures. We initially identified 206 papers which were then reduced to 167 after removing duplicates. Further review yielded 13 papers which were extensively reviewed, resulting in a final sample of six papers. Our analysis of these papers suggested that, regardless of the music intervention approach, individualized music regimens provided the best outcomes for the patient. Furthermore, music listening may act as a relaxation technique and therefore provide a long-term impact for the patient, while active music therapy may acts to engage participants through social interaction and provide acute benefits. Our findings suggest that music techniques can be utilized in various ways to improve behavior and cognition.

Our aim was to evaluate the temporal changes in left ventricular (LV) diastolic filling in relation to other LV parameters using cardiac MRI (CMR) in patients with HER2 positive breast cancer receiving trastuzumab therapy. Fourty-one women with early stage HER2+ breast cancer underwent serial CMR (baseline, 6, 12, and 18 months) after initiation of trastuzumab therapy. A single, blinded observer measured LV parameters on de-identified CMRs in random order. Linear mixed models were used to investigate temporal changes. Compared to baseline, there were significant decreases in systolic function as measured by both left ventricular ejection fraction (LVEF) (p0.001 at 6 and 12 months) and peak ejection rate corrected for end-diastolic volume (PER/LVEDV) (p = 0.008 at 6 months, p = 0.01 at 12 months). However, these differences were no longer significant at 18 months. In contrast, significant reductions in diastolic function as measured by LV peak filling rate corrected for end-diastolic volume (PFR/LVEDV) were observed at 6 months (p = 0.012), 12 months (p = 0.031), and up to 18 months (p = 0.034). There were no significant temporal changes in the time to peak filling rate corrected for cardiac cycle (TPF/RR). The reduction in PFR/LVEDV at 18 months was no longer significant when corrected for heart rate. In conclusion, there were significant subclinical deleterious effects on both LV systolic and diastolic function among patients receiving trastuzumab. While there was recovery in LV systolic function after therapy cessation at 18 months, reduction in PFR/LVEDV appeared to persist. Thus, diastolic dysfunction may serve as a marker of trastuzumab-induced cardiotoxicity that needs to be confirmed in a larger study.

Introduction: The purpose of this study was to determine the variety and prevalence of renal and non-renal abnormalities detected on multidetector computed tomography (MDCT) that precluded patients from donating a kidney.Methods: Institutional review board approval was obtained and the requirement for informed consent was waived. A retrospective, single-centre review of 701 patients (444 female, 257 male; age range 18–86 years; mean age 43.2±11.9 years) that underwent renal donor protocol MDCT was conducted. A systematic review of the CT report, records from multidisciplinary renal transplantation rounds, and electronic medical records was performed to determine which patients were approved or declined as live renal donors. If declined as a donor, CT-identified reasons were categorized as abnormalities of renal vasculature, renal parenchyma, collecting system, or extra-renal.Results: A total of 81 patients were excluded as renal donors on the basis of CT findings. Abnormalities of the collecting system accounted for the most frequent cause of exclusion (n=41), with asymptomatic renal calculi being detected in 39 patients. Complex vascular anatomy and vascular abnormalities resulted in the exclusion of 29 patients. Supernumerary arteries and early arterial branching resulted in the exclusion of 20 patients, while renal vein anomalies leading to exclusion were uncommon (n=2). Abnormalities of renal parenchyma resulted in the exclusion of nine patients. Three patients were diagnosed with autosomal dominant polycystic kidney disease, two patients had renal cell carcinoma, and two patients had areas of cortical scarring. A complex cystic lesion requiring surveillance imaging was encountered in one patient and a large area of renal infarction related to prior adrenalectomy was demonstrated in one patient. Extra-renal abnormalities leading to exclusion were limited to two patients with pulmonary nodules.Conclusions: MDCT plays a critical role in the preoperative assessment of potential renal donors by identifying contraindications to donor nephrectomy and providing accurate vascular mapping. This study is anticipated to be informative for those involved in the workup of potential living renal donors by quantifying the incidence and reasons for donor exclusion identified on CT.

Background There are limited data on the effects of trastuzumab on the right ventricle (RV). Therefore, we sought to evaluate the temporal changes in right ventricular (RV) structure and function as measured by cardiovascular magnetic resonance (CMR), and their relationship with left ventricular (LV) structure and function in breast cancer patients treated with trastuzumab. Methods Prospective, longitudinal, observational study involving 41 women with HER2+ breast cancer who underwent serial CMR at baseline, 6, 12, and 18 months after initiation of trastuzumab. A single blinded observer measured RV parameters on de-identified CMRs in a random order. Linear mixed models were used to investigate temporal changes in RV parameters. Results Of the 41 women (age 52 ± 11 years), only one patient experienced trastuzumab-induced cardiotoxicity. Compared to baseline, there were small but significant increases in the RV end-diastolic volume at 6 months (p = 0.002) and RV end-systolic volume at 6 and 12 months (p

Introduction Although cardiovascular risk factors (CVRFs) have been identified as important risk factors for both major depression and cognitive decline in later life, their association with neuropsychiatric symptoms (NPS) has not been fully elucidated. Furthermore, CVRFs, particularly hypertension, hypercholesterolemia, and diabetes, may ultimately lead to physical conditions such as small vessel disease known to disrupt cognition, thereby leading to the onset of NPS. Thus, a better understanding of the association between CVRFs and NPS could improve the development of treatments and preventative measures for NPS. Methods Using baseline data from the Prevention of Alzheimer's Dementia with Cognitive Remediation plus Transcranial Direct Current Stimulation (PACt-MD) study, a multi-site intervention study targeting older patients with depression and cognitive decline, we analysed the distribution of CVRFs (Framingham risk scores; Hachinski ischemic score; presence of hypertension, hypercholesterolemia, hyperlipidemia, diabetes, and smoking) in patients with and without NPS as determined by a score of 1 and above or 0 on the Neuropsychiatric Inventory-Questionnaire (NPI-Q). Participants fell into one of the following three diagnosis groups: Mild Cognitive Impairment (MCI) with a lifetime history of major depression (MDD); MCI without MDD; and MDD without MCI. Comparisons of distributions of CVRFs between NPI positive and negative groups were conducted using the non-parametric Mann-Whitney U test at a significance level of Results In a combined sample of 140 participants, there were no significant differences in any CVRF between positive and negative total NPI groups. However, some NPI subscale scores, notably agitation/aggression, anxiety, disinhibition, irritability, and night-time behaviour were significantly associated with increased CVRFs (p Conclusions None of the CVRFs were associated with overall total NPI-Q scores, however, these preliminary analyses suggest that some specific CVRFs were associated with certain NPI-Q subdomains. This suggests that CVRFs contribute to specific NPS domains rather than overall NPS burden. This research was funded by This project has been made possible by Brain Canada through the Canada Brain Research Fund, with the financial support of Health Canada and the Chagnon Family.

Introduction Cardiovascular risk factors are associated with both cognitive impairment and depression. However, the extent to which these factors are associated with cognitive impairment in patients with mild neurocognitive disorder with and without a history of lifetime depression needs to be clarified. Methods We looked at the distribution of Framingham Risk Scores (FRS) for cardiovascular disease in three groups of participants age 60 years and older in the Prevention of Alzheimer's Dementia with Cognitive Remediation plus Transcranial Direct Current Stimulation (PACt-MD) study: those with mild cognitive impairment (MCI; n = 42), remitted major depressive disorder (MDD, n =29), or MCI plus remitted MDD (n = 21). We also examined the association between cardiovascular risk factors and cognitive scores on the Mini-Mental State Examination (MMSE) or Montreal Cognitive Assessment (MOCA), and the Montgomery–Asberg Depression Rating Scale (MADRS) using the non-parametric Spearman's rank order correlation test. Results There were no differences in the severity of FRS across the three diagnostic groups (p=0.281). Comparison of age, gender, education, and cognitive scores across FRS severity groups showed a significant correlation of increased FRS severity with higher age (p=0.016) and lower MOCA (p=0.023). When we assessed the correlation between specific cardiovascular risk factors (i.e hypertension, hypercholesterolemia, smoking, diabetes, hyperlipidemia) and MMSE, MOCA, and MADRS, the only significant correlation was found to be between a history of hypertension and lower MOCA scores (p=0.001). Conclusions The similar FRS distribution across MDD and MCI provides further support for the association of cardiovascular burden with both MDD and cognitive impairment. Hypertension was the only cardiovascular risk factor that was correlated with cognitive impairment. Future research is needed to clarify the mechanism behind this association. This research was funded by This Project has been made possible by Brain Canada through the Canada Brain Research Fund, with the financial support of Health Canada and the Chagnon Family.

Introduction Neuropsychiatric symptoms (NPS) are common in Alzheimer's Disease (AD) and Mild Cognitive Impairment (MCI) but their association with disease biomarkers remains unknown. The aim of this systematic review is to identify potential cerebrospinal fluid (CSF) biomarkers of neuropsychiatric symptoms in Alzheimer's disease (AD) and MCI based on a systematic review of the current literature. Methods We developed a pre-defined search strategy focused on the association between CSF biomarkers and NPS in patients with AD/MCI using an extensive list of relevant keywords and controlled vocabulary. The search was then performed on four databases: Pubmed, EMBASE, Cochrane, and PsycINFO. 8838 results were recorded and screened by 2 independent reviewers. Studies were selected for critical appraisal based on our inclusion/exclusion criteria. Inclusion criteria were defined as, (1) Study must be in English (2) at least one AD CSF biomarker has been measured (3) at least one NPS from the neuropsychiatric inventory (NPI) has been assessed (4) study population should at least include patients with AD or MCI (5) some type of statistical analysis has been done in an effort to elaborate the association between an AD CSF biomarker and the status of NPS. Furthermore, Non-English, animal and review studies or studies not including an NPS, AD CSF biomarker or AD/MCI patients were excluded. Eventually, a total of 23 studies qualified for the final systematic review and are presented in the study Results Among all neuropsychiatric symptoms, depression was the most evaluated NPS followed by sleep, psychosis, anxiety, agitation/aggression, eating/appetite, apathy, and irritability. Most studies have reported conflicting results regarding the presence/absence of any significant association between any NPS with any of the AD CSF biomarkers. However, the NPS of agitation/aggression was significantly related to at least one CSF biomarker across all the studies evaluating this NPS. Conclusions Our study has revealed agitation/aggression as the most consistent NPS related to AD CSF pathology based on a review of the current literature. However, multiple studies have also revealed a conflicting relationship between AD CSF biomarkers and other NPS. Future studies are required to clarify these associations. Future studies should also focus on other NPS such as elation/euphoria, motor disturbances, and disinhibition as it seems to be the neglected domains in previous studies. Our study has also revealed a great degree of heterogeneity among studies, hence calling for a more standardized “objective” approach for the evaluation of NPS in dementia. This research was funded by Not Applicable

Introduction Objective: Neuropsychiatric symptoms (NPS) are a key characteristic and known biomarker of Alzheimer's disease (AD). Our study investigates the potential of NPS as measured by the Neuropsychiatric Inventory score (NPI) to predict progression from Mild Cognitive Impairment (MCI) to AD. In addition, we have analyzed the trajectory of NPS in comparison to global cognitive scores. Introduction NPS are common in MCI and based on prior studies they are a significant risk factor for progression to AD. Working memory and episodic memory are also known to decline with progression of AD. Cognitive tests such as MMSE have been utilized to track patients’ level of cognition and the decline in these cognitive tests is a well-known predictor of dementia. However, how NPI scores relate to cognitive test scores in predicting progression to AD is still unknown. We propose to analyze NPI (total score and sub scores) longitudinally for 6 years and to compare scores between MCI- converters (MCI-C) and MCI- non converters (MCI-NC). We hypothesize that converters may have higher scores compared to non-converters. In addition, we expect that MMSE score should correlate inversely with NPI score. Symptoms associated with progression to AD that are prevalent in our study should match those that are shown in previous studies (depression, delusion, agitation, and apathy.) Methods We selected 150 subjects from Alzheimer's Disease Neuroimaging Initiative phase 3 (36 MCI-C and 114 MCI-NC). The only inclusion criteria were that subjects must have NPI scores at two or more time points. Gender, age, and education were matched across all subjects. To measure NPI scores longitudinally, subjects were divided into two groups, MCI-C and MCI-NC. We also grouped subjects according to their NPI scores to measure their cognition using MMSE: healthy (N=55), mild (NPI score= 1-9, N=65), and severe (NPI score= 10 and above, N=30). The NPI total score and MMSE were measured across 6 years and compared at 12-month intervals. All statistical analyses were performed using SPSS 25. Analyses of variance (ANOVA) were used to compare MCI-C and MCI-NC group differences. If the assumption of homogeneity was violated, Brown-Forsythe Test p-value was reported instead. Post-hoc analyses was done by using Gabriel and Dunnett's T3 test. The 12 NPI sub scores were also counted as percentage to analyse the progression of NPS. Results The NPI total scores at all time points for the duration of 6 years were significantly different between MCI-C and MCI-NC (p Conclusions Our study has confirmed previous findings that NPI scores increased with progression of clinical symptoms from MCI to AD in MCI-C relative to MCI-NC. In addition, MMSE scores varied between NPI groups at all time points after baseline. Both of the scores showed a deteriorating trend in their respective scale in MCI-C relative to MCI-NC. This research was funded by Data collection and sharing for this project was funded by the Alzheimer's Disease Neuroimaging Initiative (ADNI) (National Institutes of Health Grant U01 AG024904) and DOD ADNI (Department of Defense award number W81XWH-12-2-0012). ADNI is funded by the National Institute on Aging, the National Institute of Biomedical Imaging and Bioengineering, and through generous contributions from the following: AbbVie, Alzheimer's Association; Alzheimer's Drug Discovery Foundation; Araclon Biotech; BioClinica, Inc.; Biogen; Bristol-Myers Squibb Company; CereSpir, Inc.; Cogstate; Eisai Inc.; Elan Pharmaceuticals, Inc.; Eli Lilly and Company; EuroImmun; F. Hoffmann-La Roche Ltd and its affiliated company Genentech, Inc.; Fujirebio; GE Healthcare; IXICO Ltd.; Janssen Alzheimer Immunotherapy Research & Development, LLC.; Johnson & Johnson Pharmaceutical Research & Development LLC.; Lumosity; Lundbeck; Merck & Co., Inc.; Meso Scale Diagnostics, LLC.; NeuroRx Research; Neurotrack Technologies; Novartis Pharmaceuticals Corporation; Pfizer Inc.; Piramal Imaging; Servier; Takeda Pharmaceutical Company; and Transition Therapeutics. The Canadian Institutes of Health Research is providing funds to support ADNI clinical sites in Canada. Private sector contributions are facilitated by the Foundation for the National Institutes of Health ( www.fnih.org ). The grantee organization is the Northern California Institute for Research and Education, and the study is coordinated by the Alzheimer's Therapeutic Research Institute at the University of Southern California. ADNI data are disseminated by the Laboratory for Neuro Imaging at the University of Southern California.

We examine a time of flight (TOF) approach for the analysis of contrast enhanced 4D volumetric CT angiography scans to derive and display blood velocity in arteries. Software was written to divide blood vessels into a series of cross sections and to track contrast bolus TOF along the central vessel axis, which was defined by a user, from 4D CT source data. Time density curves at each vessel cross section were fit with quadratic, Gaussian, and gamma variate functions to determine bolus time to peak (TTP). A straight line was used to plot TTP versus vessel path length for all three functions and the slope used to calculate intraluminal velocity. Software was validated in a simulated square channel and non-pulsatile flow phantom prior to the calculation of blood velocity in the major cerebral arteries of 8 normal patients. The TOF algorithm correctly calculates intra-luminal fluid velocity in eight flow conditions of the CT flow phantom where quadratic functions were used. Across all conditions, in phantoms and in vivo, the success of calculations depended strongly on having a sufficiently long path length to make measurements and avoiding venous contamination. Total blood flow into the brain was approximately 17 % of a normal 5 L cardiac output. The technique was explored in vivo in a patient with subclavian steal syndrome, in the pulmonary arteries and in the iliac artery from clinical 4D CT source data. Intravascular blood velocity and flow may be calculated from 4D CT angiography using a TOF approach.