Angiography Perfusion Research Articles

Perfusion Angiography in the Prediction of Wound Healing in Endovascular Treatment of Critical Limb Ischemia: Translating Imaging Parameters into Clinical Outcomes

Perfusion Angiography in the Prediction of Wound Healing in Endovascular Treatment of Critical Limb Ischemia: Translating Imaging Parameters into Clinical Outcomes

Far-Lateral Craniotomy for Posterior Inferior Cerebellar Artery to Occipital Artery Bypass: 2-Dimensional Operative Video.

Posterior inferior cerebellar artery (PICA) aneurysms are infrequent compared with other intracranial aneurysms and are more commonly distal in origin (35% of PICA aneurysms are distal vs 6.5% of other aneurysms). This makes PICA aneurysms a surgical challenge that requires careful consideration of the patient's angiographic anatomy and perfusion needs before deciding on the appropriate intervention. This patient had a highly calcified left PICA p2 segment aneurysm, which was not favorable for endovascular intervention. An end-to-side anastomosis of the occipital artery to the p3 PICA segment was performed. This anastomosis was achieved with 11-0 suture. A permanent clip was then placed along the vertebral artery occluding both the proximal PICA and the aneurysm. Indocyanine green angiography was performed to demonstrate bypass and PICA patency. The patient gave informed consent for surgery and video recording. Institutional review board approval was deemed unnecessary. Used with permission from Barrow Neurological Institute, Phoenix, Arizona.

P3395Arrival time at hyperemia of below the ankle as a determinant factor for limb salvage: evaluation by 2 dimension perfusion angiography

Abstract Background In patients with critical limb ischemia, it is desirable to obtain enough skin perfusion pressure (SPP) levels through revascularization. 2D-perfusion angiography is an emerging technology for the quantification of tissue perfusion consisted of 6 parameters calculated by time-density curve of digital subtraction angiography (DSA). Purpose We evaluated the feasibility of 2D-perfusion angiography for below the knee (BTK) endovascular therapy (EVT). We aimed to clarify which angiographical parameters of lower limb are related to SPP after EVT. Methods Consecutive 33 limbs (mean age 74.5 years, men 55%), which successfully underwent EVT for isolated BTK lesions, were enrolled in this study. We excluded Rutherford 6 limbs with severe gangrene or tissue loss, consequently 26 limbs were Rutherford 4 or 5 critical limb ischemia. We treated total 47 lesions, including 26 chronic total occlusive lesions. 5Fr guiding sheath was advanced to popliteal artery. DSA images were obtained by mechanical contrast infusion. We quantified indexed blood flow on below the ankle area by using 2D-perfusion angiography, and examined 6 parameters [arrival time (AT), time to peak (TTP), wash-in rate, width, area under the curve and mean transit time (MTT)] from acquired DSA. Hyperemia was induced by 20mg papaverine intra-arterial infusion through the guiding sheath. Results The parameters except wash-in rate were significantly shortened after hyperemia induced by intra-arterial papaverine infusion below the ankle region. Dorsal and plantar SPP were significantly correlated with hyperemic AT, hyperemic wash-in rate and AT ratio (hyperemic/rest) of lower ankle regions after EVT. However, only AT ratio was independently associated with dorsal SPP in multivariate analysis (P=0.032). A receiver operating characteristic curve showed hyperemic AT <4.5 seconds and AT ratio <0.49 predicted to obtain SPP levels >50 mmHg after EVT with the area under the curve of 0.71 (95% confidence interval, 0.52–0.90) and 0.73 (95% confidence interval, 0.55–0.90), respectively. Representative Case of 2D-perfusion Conclusion Hyperemic AT <4.5 seconds and AT ratio <0.49 of lower ankle regions may be essential to obtain the sufficient levels of SPP for limb salvage after BTK intervention. 2D perfusion angiography technique at hyperemic condition is feasible and has the potential to monitor lower limb tissue perfusion through EVT and to optimize the interventional treatment.

Prediction of MACE by Angiographic Perfusion Score (APS) in Risk Stratification following Percutaneous Coronary Stenting in STEMI without Thrombolytic Therapy

Background: ST-elevation myocardial infarction (STEMI) is a major cause of mortality worldwide. PCI remain gold standard management of STEMI. An Angiographic Perfusion Score (APS) is a combination of TIMI Flow Grades (TFG) and myocardial perfusion (TMPG) grades before and after PCI. So it can accurately measure both epicardailand myocardial perfusion and predict major adverse cardiac events (MACE). The aim of the study is to evaluate the association of APS for determining the short term clinical outcomes after PCI in ST-segment elevation myocardial infarction without thrombolytic therapy. Methodology: This cross sectional observational study carried out among adult patients presenting STsegment elevation myocardial infarction without thrombolytic pretreatment to the cardiology department of BSMMU who underwent Percutaneous Coronary Intervention and met inclusion and exclusion criteria. This study was conducted from April 2017 to March 2018. After informed written consent data collection was carried out by using a data sheet. Calculated sample size of the study was 205. Angiogram was done by SIEMENS AXOM ARTIS machine, CD Analysis to see TFG & TMPG for calculation of APS was done by two specialist observer (Professor, Associate or Assistant Professor) MACE was observed within 30 days. Chi square test was done to see the association of APS with MACE by Statistical Package for Social Science program 20 version of computer on the basis of different variables. Results: MACE distribution of the study patients revealed that only 7.8% of the patients had MACE whereas 92.2% of the patients had no MACE among 205 patient APS score with MACE distribution of the study patients revealed that 9.3% patient of partial perfusion group and 44.4% patient of failed perfusion group had MACE but there were no major adverse cardiac event in full perfusion group of patient. The difference were statistically highly significant (p<0.05) among three groups but there were no differences in the baseline characteristics of those who had full, partial or failed perfusion of APS. Conclusion: APS which combines TFG with TMPG before and after PCI is a better discriminator of 30 day MACE than TMPG or TFG alone taken only after PCI. It can identify high risk patients who need implementation of early invasive strategies. We conclude that APS is a better predictor of MACE to take care of patient more accurately.
 University Heart Journal Vol. 15, No. 1, Jan 2019; 16-21

Change in Perfusion Angiography During Transcatheter Arterial Chemoembolization for Hepatocellular Carcinoma Predicts Short-Term Outcomes.

OBJECTIVE. The purpose of this study is to quantitatively assess perfusion reductions occurring in hepatocellular carcinoma (HCC) during transcatheter arterial chemoembolization (TACE) using 2D perfusion angiography and to evaluate the relationships between various 2D perfusion angiography parameter changes and short-term tumor response. SUBJECTS AND METHODS. This prospective study included 172 patients (144 men and 28 women; mean [± SD] age, 65.4 ± 10.2 years) who underwent TACE for HCC between November 2015 and November 2017. Two-dimensional perfusion angiography was performed before and after TACE. Pre- and postprocedural CT images were also reviewed. Index lesions were defined as all discrete lesions 1.5 cm or larger. The tumor response was assessed using the modified Response Evaluation Criteria in Solid Tumors. Periprocedural 2D perfusion angiography parameters, including the arrival time, time to peak, wash-in rate, width, AUC, and mean transit time, were compared using the Wilcoxon signed rank test. Correlations between 2D perfusion angiography parameter changes and objective tumor response were evaluated using multivariate logistic regression analysis. RESULTS. A total of 187 lesions meeting the inclusion criteria were identified in 172 patients. All analyzed 2D perfusion angiography parameters were significantly different after versus before TACE (p < 0.001). A significant relationship between periprocedural change in AUC and short-term tumor response was found (odds ratio, 1.535; 95% CI, 1.314-1.793; p < 0.001). CONCLUSION. Two-dimensional perfusion angiography could objectively quantify perfusion reductions and predict short-term tumor response to TACE in patients with HCC.

Abstract TP69: Three-Phase Helical Computed Tomographic Angiography Perfusion Maps Predict Final Infarction in the Acute Ischemic Stroke Setting

Background: Three-phase helical CTA can provide information on parenchymal hemodynamics distal to the occlusion, similar to CT perfusion (CTP). Helical CTA is a less expensive and a more widely available modality. We propose two perfusion map algorithms applied to three-phase helical CTA, providing optimal thresholds for prediction of final infarct volume Methods: 44 stroke patients with occlusion visible on CTA were acutely imaged with three-phase CTA (temporal sampling was 8 seconds). MR diffusion weighted imaging (DWI) between 24-48 hours were used to measure final infarct volume. The three-phase helical CTA perfusion maps were denoted “Delay” and “Flow Average” (see Figure 1). The maps were filtered using a 3D Gaussian blurring technique. The maps were generated for all patients, then a receiver operating characteristic (ROC) curve was generated for the merged patient data, comparing infarct vs. normal tissue. Thresholds were determined using ROC curves by optimizing sensitivity and specificity. Results: The “Delay” map generated an ROC curve with an Area-Under-Curve (AUC) of statistical significance. The “Flow Average” map generated an ROC curve with an Area-Under-Curve (AUC) of statistical significance. Conclusion: The proposed “Delay” and “Flow Average” perfusion maps applied to three-phase CTA predicted final infarct volume to a high degree of accuracy, close to CTP accuracies from the literature. These results show the capability of three-phase helical CTA to generate quantitative perfusion maps which will be useful for non-tertiary centers that do not have access to expensive post-processing software.

Significance of Renal Perfusion Angiography and Biochemical Indicators in Early Diagnosis of Type 2 Diabetic Nephropathy

Background: Although there are many biochemical indicators to reflect changes in renal function, but these indicators can not reflect renal damage timely and accurately. Renal microcirculation changes can not be reflected also. This study amied at evaluate significance of renal perfusion angiography and the indexes of relevant biochemical in early diagnosis of type 2 diabetic nephropathy. Methods: 30 I-III T2DN patients (DN group) and 25 healthy volunteers (control group) were studied, and both of groups were performed renal perfusion CT angiography imaging examination. Biochemical indexes, which are fasting blood glucose (FBG), urinary albumin excretion rate (UAE), 24 h urine protein quantitation (UPQ), blood urea nitrogen (BUN), serum creatinine (Scr), Cystatin C(Cys C), random albumin to creatinine ratio(ACR), were measured in both of groups, then simplified MDRD (Modification of Diet in Renal Disease) and Cys C equation were used to calculate the Estimated Glomerular Filtration Rate(eGFR). double-renal perfusion contrast scanning in both of groups were also conducted to obtain data of double renal blood flow (BF), blood volume (BV), mean transit time (MTT), and permeability surface (PS) for statistical analysis. Results: The indexes of BF, MTT and FBG, UAE, 24 h UPQ, ACR, Cys C, eGFR were found to have relative strong correlation and statistical significance (P<0.05). BF was shown the negative correlation with those indexes, however MTT had positive correlation with them. The area under ROC (receiver operating characteristic curve), were more than 0.9 for UAE, ACR, NF, and MTT, and it indicate that these indexes have relatively positive effect on the early diagnosis of the DN. For 24 h UPQ, cysteine C, eGFR and BV value, the area Under the curve are between 0.7 and 0.9, which indicates that diagnosis using those index for the disease were accuracy. Thus, the above indexes have better diagnostic efficiency compared to Scr, BUN and eGFR. Conclusion: The biochemical indexes such as UAE, ACR and renal perfusion indexes such as BF and MTT can be applied in the early predicative diagnosis and DN screening. Its diagnosis effect is better than other biochemical indexes.

Effect of Intracranial Pressure Control on Improvement of Cerebral Perfusion After Acute Subarachnoid Hemorrhage: A Comparative Angiography Study Based on Temporal Changes of Intracranial Pressure and Systemic Pressure

Increased intracranial pressure (ICP) is a well-known complication after aneurysmal subarachnoid hemorrhage (aSAH). This study focused on the different temporal changes in ICP, mean arterial pressure, and cerebral perfusion pressure at the early stage of aSAH, throughout aneurysm embolization, and their effects on improvement in angiographic perfusion patterns. Twenty-seven patients with aSAH were evaluated who underwent coiling and cerebrospinal fluid (CSF) drainage. Diagnostic angiography was performed to confirm the presence and location of the vascular lesion. The transit time of the capillary filling phase was defined as a surrogate of cerebral perfusion. Capillary filling transit times were compared before and after CSF drainage. Univariate and multivariate analyses were performed to identify associations between different physical parameters and capillary filling transit times. By univariate analysis, average capillary transit time before CSF drainage had a significant correlation with initial ICP (P= 0.0004; R2= 0.398) but not systemic pressure (mean arterial pressure or cerebral perfusion pressure). Improvement in capillary filling pattern (i.e., a decrease in angiographic capillary transit time after CSF drainage) was seen in patients with high initial ICP and correlated with ICP difference after ventricular drainage (P= 0.0001 and P < 0.0001, respectively). Using multivariate regression analysis, improved control in postprocedural ICP levels significantly correlated with angiographic evidence of improved cerebral perfusion (P= 0.0243). Decreasing ICP by CSF drainage strongly correlated with improved cerebral microcirculation after aSAH. Further development of ICP control protocols that can provide better ICP management of patients with aSAH is warranted.

Efficacy of Two-Dimensional Perfusion Angiography for Evaluations after Infrapopliteal Bypass Surgery for Critical Limb Ischemia.

Two-dimensional perfusion angiography (2DPA) is utilized in hybrid operating rooms. 2DPA produces color map images and functional parameters to provide more robust visual and quantitative evaluations than conventional angiography. Its efficacy was suggested in five patients following bypass surgery; unexpected results were obtained in one patient, leading to a decision to perform surgical re-anastomosis. Furthermore, we found that the general anesthesia eliminates body movements that tend to disrupt 2DPA results. 2DPA was more useful during surgical revascularization than conventional angiography and provided more detailed information.

3:18 PM Abstract No. 53 Changes in two-dimensional perfusion angiography before and after inferior vena cava filter retrieval

To investigate differences in hemodynamic flow parameters acquired in two-dimension (2D) perfusion angiography before and after inferior vena cava (IVC) filter retrieval. IVC filter retrievals at a single institution were retrospectively reviewed. Standardized breath-hold, digital subtraction angiography was performed at 2-3 frames per second before and after removal, and 2D-perfusion images were reconstructed on a dedicated workstation (Philips Allura Xper FD20, Philips Medical Systems, Best, Netherlands). Changes in the density per pixel per second within a region of interest (ROI) were used to calculate contrast arrival time, time-to-peak (TTP), wash-in-rate (WIR), area under the curve (AUC), and mean transit time (MTT). Measurements were obtained inferior, superior, and at the level of the filter. Differences in the hemodynamic parameters before and after filter removal were assessed with Mann-Whitney U analysis. A p-value of <0.05 was considered statistically significant. At the level of the filter, the TTP was significantly longer before filter removal when compared to after, with mean times of 1.28 and 0.78 seconds, respectively (p = 0.042). The MTT inferior to the filter was longer before filter removal when compared to after, with mean times of 0.8 and 0.5 seconds, respectively. The WIR inferior to the filter was longer before filter removal when compared to after, with mean of 435 and 250 HU/second, respectively. Preliminary data evaluating differences in flow parameters acquired in 2D-perfusion angiography before and after IVC filter retrieval demonstrate a significantly longer TTP when filters are in place, suggesting a functional hemodynamic delay secondary to filter presence.

Association of Changes in Macular Perfusion With Ranibizumab Treatment for Diabetic Macular Edema

Anti-vascular endothelial growth factor treatment is the first-line therapy in the treatment of center-involving diabetic macular edema. Data on capillary perfusion changes under repeated treatment in a possibly compromised vascular network are limited. To evaluate the association of repeated ranibizumab injections on macular perfusion in patients with diabetic macular edema. This study analyzed prospectively collected data from the 12-month RESTORE core study and the 24-month open label RESTORE extension study, which assessed the efficacy and safety of ranibizumab in patients with visual impairment due to diabetic macular edema. Of 345 patients with center-involving diabetic macular edema who had enrolled in the 12-month RESTORE core study, 240 entered the 24-month RESTORE extension study. Of these, 83 (34.6%) received ranibizumab, 83 (34.6%) received ranibizumab and laser combination therapy, and 74 (30.8%) received laser monotherapy in the first year of the study; 208 completed the 24-month extension study. Fluorescence angiography images were taken from each participant twice each year graded by Vienna Reading Center on severity of capillary loss in the parafoveal area, regularity of the foveal avascular zone outline, and measurement of the size of the foveal avascular zone, following a standardized protocol. Data analysis took place from July 2014 through December 2017. Change in 3 fluorescence angiography perfusion parameters over the course of treatment. Mean (SD) patient age was 62.6 (8.8) years; 124 of 208 (59.2%) were male and 197 of 208 (94.6%) were white. The number of patients with definite altered foveal avascular zone regularity at baseline was 103 of 240 patients (42.9%); another 118 patients (49.2%) had questionably altered regularity at baseline. Definitive capillary loss was found in 65 of 240 patients (27.1%) at baseline. Mean (SD) foveal avascular zone size at baseline was 0.261 (0.232) mm2 in ranibizumab monotherapy, 0.231 (0.219) mm2 in ranibizumab and macular laser combination therapy, and 0.201 (0.13) mm2 in laser monotherapy. No treatment arm experienced significant increase in foveal avascular zone size at any time in the study period. At month 36, ranibizumab monotherapy resulted in a mean increase of 0.073 mm2 (95% CI, 0.005-0.142 mm2) and combination therapy resulted in a mean increase of 0.117 mm2 (95% CI, 0.045-0.188 mm2), but no changes were statistically significant. No changes occurred in foveal avascular zone regularity in any treatment group, and no differences were found in capillary loss around the fovea in the 3 treatment groups; neither element could be correlated with visual acuity or central retinal thickness. Repeated ranibizumab treatment was not associated with impaired macular perfusion in our study cohort. Because our data do not suggest a harmful effect of anti-vascular endothelial growth factor therapy on capillary integrity, patients with severe microangiopathy and advanced capillary dropout should not be denied these treatments.

Состояние сосудистого русла, паренхимы и перфузии легких при хронической тромбоэмболической легочной гипертензии по данным субтракционной компьютерной томографической ангиопульмонографии

to assess the state of vascular bed, parenchyma, and perfusion of lungs in patients with chronic thromboembolic pulmonary hypertension (CTEPH) using the method of subtraction computed tomography (CT). CT pulmonary angiography (CTPA) was performed in 45 patients with verified CTEPH (18 men, 27 women, age 26-79 years) by CT scanner using the "Lung subtraction" standard protocol. Parameters analyzed were characteristics of the state of main pulmonary artery (MPA) and the right ventricle (RV), and calculated CT angiographic (CTA) obstruction and perfusion defect scores. Significant correlation was found between CTA obstruction score and perfusion defect score (r=0.34, p=0.02). Mean pulmonary arterial pressure (mPAP) correlated with MPA diameter (r=0.4, p=0.02), RV wall thickness (r=0.6, p=0.0003) and the ratio of MPA diameter to ascending aortic diameter (r=0.5, p=0.002). Significant correlation was also found between RV wall thickness and pulmonary vascular resistance (PVR) (r=0.4, p=0.04). Neither CTA obstruction score nor perfusion defect score correlated with PVR and mPAP. The data of CT did not correlate with results of 6-minute walk test. In patients with CTEPH subtraction CTPA allows carrying out complex diagnostics of the state of vascular bed, parenchyma and perfusion of the lungs.

X-ray angiography perfusion imaging with an intra-arterial injection: comparative study with 15O-gas/water positron emission tomography

BackgroundX-ray angiography perfusion (XAP) is a perfusion imaging technique based on conventional DSA.ObjectiveIn this study, we aimed to validate parameters derived from XAP by comparing them with 15O-gas/water positron emission...

Angiographic perfusion imaging of intracranial stenting

Two-dimensional angiographic perfusion imaging (2DAP) is a new technique permitting perfusion imaging during angiography, and has been used to study cerebral vasospasm. Here we report our experience with this technique following angioplasty and stent placement in a patient with symptomatic and medically refractory stenosis of the right supraclinoid internal carotid artery. We found that intraprocedural angiographic perfusion imaging provided real-time and objective evidence of improved cerebral perfusion during intervention. Following treatment, the patient remains symptom-free at last follow-up.

Assessment of prognostic value of Angiographic perfusion score following Percutaneous Coronary Intervention in patients with Acute Coronary Syndrome

Assessment of prognostic value of Angiographic perfusion score following Percutaneous Coronary Intervention in patients with Acute Coronary Syndrome

Skeletal Myoblast-Seeded Vascularized Tissue Scaffolds in the Treatment of a Large Volumetric Muscle Defect in the Rat Biceps Femoris Muscle

High velocity impact injuries can often result in loss of large skeletal muscle mass, creating defects devoid of matrix, cells, and vasculature. Functional regeneration within these regions of large volumetric muscle loss (VML) continues to be a significant clinical challenge. Large cell-seeded, space-filling tissue-engineered constructs that may augment regeneration require adequate vascularization to maintain cell viability. However, the long-term effect of improved vascularization and the effect of addition of myoblasts to vascularized constructs have not been determined in large VMLs. Here, our objective was to create a new VML model, consisting of a full-thickness, single muscle defect, in the rat biceps femoris muscle, and evaluate the ability of myoblast-seeded vascularized collagen hydrogel constructs to augment VML regeneration. Adipose-derived microvessels were cultured with or without myoblasts to form vascular networks within collagen constructs. In the animal model, the VML injury was created in the left hind limb, and treated with the harvested autograft itself, constructs with microvessel fragments (MVF) only, constructs with microvessels and myoblasts (MVF+Myoblasts), or left empty. We evaluated the formation of vascular networks in vitro by light microscopy, and the capacity of vascularized constructs to augment early revascularization and muscle regeneration in the VML using perfusion angiography and creatine kinase activity, respectively. Myoblasts (Pax7+) were able to differentiate into myotubes (sarcomeric myosin MF20+) in vitro. The MVF+Myoblast group showed longer and more branched microvascular networks than the MVF group in vitro, but showed similar overall defect site vascular volumes at 2 weeks postimplantation by microcomputed tomography angiography. However, a larger number of small-diameter vessels were observed in the vascularized construct-treated groups. Yet, both vascularized implant groups showed primarily fibrotic tissue with adipose infiltration, poor maintenance of tissue volume within the VML, and little muscle regeneration. These data suggest that while vascularization may play an important supportive role, other factors besides adequate vascularity may determine the fate of regenerating volumetric muscle defects.

The value of whole-brain CT perfusion imaging and CT angiography using a 320-slice CT scanner in the diagnosis of MCI and AD patients.

To validate the value of whole-brain computed tomography perfusion (CTP) and CT angiography (CTA) in the diagnosis of mild cognitive impairment (MCI) and Alzheimer's disease (AD). Whole-brain CTP and four-dimensional CT angiography (4D-CTA) images were acquired in 30 MCI, 35 mild AD patients, 35 moderate AD patients, 30 severe AD patients and 50 normal controls (NC). Cerebral blood flow (CBF), cerebral blood volume (CBV), mean transit time (MTT), time to peak (TTP), and correlation between CTP and 4D-CTA were analysed. Elevated CBF in the left frontal and temporal cortex was found in MCI compared with the NC group. However, TTP was increased in the left hippocampus in mild AD patients compared with NC. In moderate and severe AD patients, hypoperfusion was found in multiple brain areas compared with NC. Finally, we found that the extent of arterial stenosis was negatively correlated with CBF in partial cerebral cortex and hippocampus, and positively correlated with TTP in these areas of AD and MCI patients. Our findings suggest that whole-brain CTP and 4D-CTA could serve as a diagnostic modality in distinguishing MCI and AD, and predicting conversion from MCI based on TTP of left hippocampus. • Whole-brain perfusion using the full 160-mm width of 320 detector rows • Provide clinical experience of 320-row CT in cerebrovascular disorders of Alzheimer's disease • Initial combined 4D CTA-CTP data analysed perfusion and correlated with CT angiography • Whole-brain CTP and 4D-CTA have high value for monitoring MCI to AD progression • TTP in the left hippocampus may predict the transition from MCI to AD.

Fluoropyrimidine-associated myocardial toxicity as a global metabolic effect compared to vascular spasm and visibility on FDG PET scanning.

e14013 Background: Myocardial toxicity from fluoropyrimidines is a rare but potentially serious side effect, estimated by some as occurring in up to 9%. Coronary spasm has been suggested as the underlying mechanism, despite a lack of supporting evidence and other toxicity mechanisms have been proposed. Matsubara described Krebs cycle dysfunction in the presence of 5FU with depletion of high energy phosphate compounds in rodent myocardial tissue with ECG changes. Following a chance discovery of abnormal myocardial FDG uptake on a PET scan shortly after presenting with presumed 5FU cardiac toxicity (angina, ST elevation, troponin rise; normal coronary vessels on imaging), we prospectively evaluated all instances of angina occurring during 5FU infusion with coronary artery imaging and FDG PET scan. Methods: We identified 5 patients who experienced angina during 5FU therapy. They were investigated for coronary ischaemia and also underwent PET scanning to assess myocardial FDG uptake. Data was collected from patient records, and subsequent cardiac investigations. Results: In all 5 cases, PET scan demonstrated markedly abnormal FDG uptake throughout the myocardium, with the ventricular blood pool demonstrating more FDG activity than myocardium. No significant underlying coronary artery disease was identified. All 5 patients had previous PET scans with normal myocardial FDG uptake. Conclusions: We identified a consistent pattern of abnormal FDG uptake throughout the myocardium for all scanned patients with chest pain following administration of 5FU. This was not restricted to a single arterial territory. There were no typical ECG changes of spasm. Obstructive coronary disease was excluded with angiographic imaging or myocardial perfusion scanning. The FDG PET scans suggest global myocardial metabolic change, supporting the notion of 5FU being a direct myocardial toxin inhibiting myocardial glucose utilization. The myocardium may then be dependent on fatty acid metabolism, posing additional risk to patients on low fat diets. Our data provides new insight into the mechanism of 5-FU myocardial toxicity and further prospective assessment using PET is warranted.

Feasibility of Real-Time Angiographic Perfusion Imaging in the Treatment of Cerebral Vasospasm

Background: Objective assessment and quantification of the severity of cerebral vasospasm following aneurysmal subarachnoid hemorrhage is not routinely utilized. We investigated the feasibility of angiographic perfusion imaging derived from digital subtraction angiography (DSA) following endovascular vasospasm treatment procedures. Methodology: Real-time blood flow analysis was performed using parametric color coding on pre- and postintervention DSA. Semiquantitative parenchymal perfusion parameters (arrival time [AT] of contrast, time to peak [TTP] opacification, and mean transit time [MTT] of contrast) were calculated across 3 vascular territories (anterior cerebral artery [ACA], middle cerebral artery [MCA], and lenticulostriate arteries) using standard 2-D angiographic perfusion software. The pre- and postintervention arterial vessel diameters were compared. Results: Twelve endovascular vasospasm treatments in 6 patients were performed. All patients received intra-arterial vasodilator therapy with either nimodipine, milrinone, or both. Following intra-arterial intervention, parenchymal flow analysis showed improvement in TTP and MTT across all vascular territories (p < 0.002) and improvement in AT in the ACA and MCA territories (p < 0.03). Improvement in parenchymal perfusion parameters was associated with improvement in vessel diameters in all territories following treatment (p < 0.05). Conclusion: Real-time parenchymal perfusion imaging during endovascular vasospasm treatment procedures is feasible and provides reliable semiquantitative measurement of angiographic treatment response.

Abstract 193: Real-time Quantitative Changes in Cerebral Blood Flow From Intra-arterial Vasodilator Treatment in Cerebral Vasospasm

Introduction: Intra-arterial (IA) vasodilators are key components in the treatment of cerebral vasospasm (CV) resulting from subarachnoid hemorrhage (SAH) and traumatic brain injury (TBI). Angiographic assessments of vessel caliber immediately after infusion, however, are unreliable metrics of treatment effect, and as a result there does not currently exist a clear biomarker against which to titrate treatment. Quantitative cerebral blood flow (CBF) measurements from angiographic images may better characterize treatment effect and provide real-time feedback to guide infusion protocols. Methods: From our prospectively maintained institutional registry, we identified patients treated with IA vasodilators in the anterior circulation for CV between July 2014 and June 2016. Angiograms were reviewed by an experienced neuro angiographer blinded to clinical data and subsequent imaging. Regions of interest (ROIs) were drawn by two experienced neuroimagers over the MCA territory. CBF maps were calculated automatically from immediate pre- and immediate post-infusion angiograms using perfusion angiography and averaged over the ROIs. Results: A total of 65 angiograms were evaluated from 22 patients treated with vasodilators for CV. Average age was 48 and 60% were female. Etiology of vasospasm included SAH in 83% (54/65), TBI in 14% (9/65) and stroke/vasculopathy in 3% (2/65) Degree of vasospasm varied from mild (20% (13/65)) to moderate ((62% (40/65)) and severe (18% (12/65)). All patients were treated with IA verapamil ranging from 5 mg to 30 mg over the course of 10-60 minutes. Immediate post-infusion angiograms demonstrated improved vascular caliber in 23% (15/65) cases. In comparison, CBF increased on average 11% (SD 49) after verapamil infusion. Verapamil dosage correlated with percent change in CBF (p&lt;0.05, Spearman’s correlation). Conclusions: Verapamil infusion resulted in increased CBF in patients with CV from SAH and TBI. Quantitative angiographic CBF may serve as an effective real-time biomarker of treatment efficacy.