Perfusion Volume Research Articles

Effects of hemodialysis on intraneural blood flow in end-stage kidney disease.

We quantified intraneural blood flow (INBF) in 18 patients with end-stage kidney disease (ESKD) and examined its relationship with nerve size, neuropathy severity, and nerve excitability parameters. Sonographic measurements of the median nerve were performed at the same site before and after hemodialysis. INBF was quantified by analyzing power Doppler sonograms to obtain the vessel score (VSc) and maximum perfusion intensity (MPI). Corresponding median motor nerve excitability studies were performed. Neuropathy severity was assessed using Total Neuropathy Score. A total of 39% of ESKD patients had detectable INBF compared with none in the control group (P < 0.0001). Patients with detectable INBF had larger nerves and more severe neuropathy (P < 0.01). INBF parameters were significantly reduced after a session of dialysis (VSc: P < 0.01; MPI: P < 0.01). A significant relationship was found between interdialytic change in INBF and changes in nerve excitability. Increased INBF is a potential marker for neuropathy severity in ESKD patients. Muscle Nerve 57: 287-293, 2018.

Effects Of Exercise-induced Hypohydration On Brain Structure And Function, A MRI Study

Hypohydration exceeding 2% body mass is known to impair endurance capacity. It is hypothesized that the central nervous system, specifically the brain, is negatively affected by hypohydration, leading to a decline in endurance capacity. PURPOSE: To investigate the effects of exercise-induced hypohydration on the brain. METHODS: Ten trained endurance males (mean±sd: age 23.3±1.1 years; body fat 10.5±2.4%; VO2peak 65±5 ml kg-1 min-1) were dehydrated to -3% body mass by running on a treadmill at 65% VO2peak in a 25°C environment, before drinking to replace 100% or 0% of fluid losses in two randomized, counterbalanced trials. Participants underwent MRI scans at baseline and post-fluid replacement to examine brain volume, functional activity and cerebral perfusion. Magnetic resonance spectroscopy was used to measure brain temperature (at primary motor cortex) before and during the dehydration run. Endurance capacity was assessed by running to exhaustion at 75% VO2peak. Results were assessed using paired sample T-test with p<0.05 considered significant. RESULTS: MRI results demonstrated a reduction in total brain volume in hypohydration (HH) as compared to euhydration (EU) trials (EU: 1.007, HH: 0.993; p=0.003). BOLD (blood-oxygen-level dependent) activation in the primary motor (M1) and somatosensory cortex (S1) during a plantar flexion task were similar between conditions (M1: p= 0.314, S1: p=0.332). Global and regional cerebral perfusion remained unchanged between conditions (Global: p= 0.055, M1: p= 0.447, S1: p=0.458). Brain temperature measured at baseline was higher than core temperature (Brain: 37.7±0.5°C, Core: 36.7±0.3°C; p<0.0001). However, both temperatures were similar during exercise (Brain: 38.2±0.4°C, Core: 38.6±0.3°C; p=0.110). Endurance capacity was reduced with hypohydration (EU: 45.2±9.3 min, HH: 38.4±10.7 min; p=0.033). CONCLUSION: Under hypohydration, the endurance capacity is impaired and total brain volume is reduced. Brain functional activity and cerebral perfusion are notably well-preserved. Brain temperature could be regulated within a narrower homeostatic range than the core temperature. Supported by DIRP Grant, PA No. 9015102335 and funding from ERGOTECH, South Africa.

The predictive factors of fever after percutaneous lithotripsy

Objective To analyze the predictive factors of fever after percutaneous renal stone surgery, and to provide reference for clinical treatment. Methods A total of 147 patients underwent percutaneous nephrolithotomy in after operation was chosen in the Department of Urology in our hospital from January 2014 to January 2016. According to the existence of fever, patients were divided into fever (n=25, heating rate 17.0%) and control (n=122) groups. Preoperative information were collected, including age, gender, preoperative serum creatinine, stone size and shape, the involvement of calyceal number, water, urine culture results, operative time, blood loss, intraoperative perfusion volume, pyonephrosis, puncture channel length, hospitalization time and other information including intraoperative, postoperative information including fever, and postoperative renal fistula complications if there is information. SPSS 18.0 was used for statistical analysis. Results The fever group stone surface area, CT value affected calyx number, stone shape, stone properties, the involvement of calyceal number, degree of hydronephrosis, operative time, intraoperative blood loss, intraoperative perfusion, hospitalization time, and renal fistula complication rates were higher than the control group (P 0.05). The results of Logistic regression analysis found that the stone surface area (OR=5.19), stone, stone shape (OR=7.86) properties (OR=3.87), operation time (OR=5.68), intraoperative perfusion (OR=5.24), and renal fistula complications (OR=2.65) for the influence factors of fever. Conclusions The stone surface area is large, stone nature infection stones, stone shape for staghorn calculi, longer operation time, and intraoperative perfusion of large renal fistula complications were more prone to postoperative fever in postoperative. Key words: Nephrostomy, percutaneous/AE; Fever/CO; Forecasting

Predictive value of perfusion defects on dual energy CTA in the absence of thromboembolic clots

BackgroundTo determine the predictive value of volumetrically measured lung perfusion defects (PDvol) and right ventricular dysfunction on dual-energy computed tomography angiography (DE-CTA) for predicting all cause mortality in patients suspected of pulmonary embolism (PE) but without evident thromboembolic clot on CTA. Methods448 patients underwent DE-CTA on a 64-channel DSCT system between January 2007 and December 2012 for suspected PE, of which 115 were without detectable thromboembolic clot on CTA. Diagnostic performance for identifying patients at risk of dying was evaluated using ROC analysis. All-cause mortality was assessed via the hospital electronic medical records and/or consultation of the patient or the patient's primary care physician via phone call interviews. Sensitivity, specificity, positive likelihood ratio, negative likelihood ratio and area under the curve (AUC) were determined for PDvol (volume of perfusion defects/total lung volume), transverse right ventricular to left ventricular diameter ratios (RV/LV) and for the combination of both tests. ResultsMortality was 38% within the investigated time period of 6 months. Patients who died had significantly higher PDvol (PDvol 28 ± 13% vs. 19 ± 12%, p < 0.001) and a non-significant difference in transverse RV/LV ratio (1.14 ± 0.37 vs. 1.06 ± 0.22, p = 0.159). The AUC was 0.71 for PDvol, 0.53 for RV/LV ratio, and 0.67 for the combination of PDvol and RV/LV ratio. PDvol remained a significant predictor after correcting for age. ConclusionsIn the absence of thromboembolic clots, PDvol at DE-CTA appears to be predictive for all cause mortality.

Prospective comparison of biphasic contrast‐enhanced CT, volume perfusion CT, and 3 Tesla MRI with diffusion‐weighted imaging for insulinoma detection

To evaluate the diagnostic performance of biphasic contrast-enhanced CT (CECT), volume perfusion CT (VPCT) and 3 Tesla MRI with diffusion-weighted imaging (DWI), in patients with clinically suspected insulinomas. This prospective study was approved by the institutional review board. Sixty-four patients with clinically suspected insulinomas underwent biphasic CECT, VPCT, and 3T MR with DWI. Two radiologists independently determined the presence/absence of tumor using a 5-scale confidence level. Conspicuity of the lesion and clarity of tumor-to-pancreatic duct distance were graded. Receiver operating characteristic analysis was performed to compare diagnostic performance. Forty-seven patients were tumor positive, with 51 tumors. The differences between the areas under the curve values for tumor detection were as follows: 0.715 (CECT), 0.903 (VPCT), 0.832 (MRI without DWI) and 0.955 (MRI with DWI) for reader 1, and 0.738 (CECT), 0.895 (VPCT), 0.841 (MRI without DWI), and 0.956 (MRI with DWI) for reader 2. MRI with DWI and VPCT were significantly more accurate than CECT for insulinoma detection (P = 0.01 and 0.02 for reader 1, and P = 0.01 and 0.03 for reader 2). Lesion conspicuity was better on MRI compared with VPCT (P = 0.01), and both were better than CECT (both P < 0.01). Tumor-to-pancreatic duct distance was better appreciated on MRI, compared with CECT and VPCT (both P < 0.01). The weighted k values indicate good to excellent agreement between observers for determining tumor presence/absence (k = 0.64-0.84). The 3T MRI with DWI and VPCT are significantly more accurate than CECT for insulinoma detection. MRI demonstrates higher tumor conspicuity and is superior in depicting the tumor-to-duct distance. 1 Technical Efficacy: Stage 3 J. Magn. Reson. Imaging 2017;46:1648-1655.

A first-in-human, double-blind, placebo-controlled, randomized, dose escalation study of DWP05195, a novel TRPV1 antagonist, in healthy volunteers.

ObjectivesDWP05195 is a transient receptor potential vanilloid 1 (TRPV1) antagonist developed for managing pain. The purpose of this study was to evaluate the pharmacodynamics pharmacokinetics, safety, and tolerability of DWP05195 in healthy subjects. This was a first-in-human randomized, double-blinded, placebo-controlled, dose escalation study.Subjects and methodsDWP05195 or placebo was administered as a single dose of 10–600 mg in the single-dose study and as 100–400 mg once daily for 8 days in the multiple-dose studies. Each study group consisted of 10 subjects (study drug-to-placebo ratio was 8:2). For pharmacodynamics assessment, the heat pain threshold (HPtr), heat pain tolerance (HPtol), perfusion intensity, and flare area ratio of cutaneous blood flow were measured. Safety and tolerability were evaluated throughout the study.ResultsThe maximum plasma concentrations and area under the plasma concentration–time curve from zero to the last measurable time dose-dependently increased. HPtr and HPtol tended to increase more after DWP05195 administration than after placebo administration. HPtr and HPtol tended to dose-dependently increase after administration of DWP05195. Cutaneous blood flow was reduced as the dose of DWP05195 increased during the multiple-dose study. DWP05195 was well tolerated up to 600 and 400 mg single- and multiple-dose administrations, respectively.ConclusionThe pharmacological activity of DWP05195, measured using HPtr and HPtol, increased as expected in a dose-dependent manner owing to increased systemic exposure, indicating that DWP05195 can be used as a TRPV1 antagonist for pain management.

Interpretative Guidelines and Possible Indications for Indocyanine Green Fluorescence Imaging in Robot-Assisted Sphincter-Saving Operations.

Since the introduction of indocyanine green angiography more than 25 years ago, few studies have presented interpretative guidelines for indocyanine green fluorescent imaging. We aimed to provide interpretative guidelines for indocyanine green fluorescent imaging through quantitative analysis and to suggest possible indications for indocyanine green fluorescent imaging during robot-assisted sphincter-saving operations. This is a retrospective observational study. This study was conducted at a single center. A cohort of 657 patients with rectal cancer who consecutively underwent curative robot-assisted sphincter-saving operations was enrolled between 2010 and 2016, including 310 patients with indocyanine green imaging (indocyanine green fluorescent imaging+ group) and 347 patients without indocyanine green imaging (indocyanine green fluorescent imaging- group). We tried to quantitatively define the indocyanine green fluorescent imaging findings based on perfusion (mesocolic and colic) time and perfusion intensity (5 grades) to provide probable indications. The anastomotic leakage rate was significantly lower in the indocyanine green fluorescent imaging+ group than in the indocyanine green fluorescent imaging- group (0.6% vs 5.2%) (OR, 0.123; 95% CI, 0.028-0.544; p = 0.006). Anastomotic stricture was closely correlated with anastomotic leakage (p = 0.002) and a short descending mesocolon (p = 0.003). Delayed perfusion (>60 s) and low perfusion intensity (1-2) were more frequently detected in patients with anastomotic stricture and marginal artery defects than in those without these factors (p ≤ 0.001). In addition, perfusion times greater than the mean were more frequently observed in patients aged >58 years, whereas low perfusion intensity was seen more in patients with short descending mesocolon and high ASA classes (≥3). The 300 patients in the indocyanine green fluorescent imaging- group underwent operations 3 years before indocyanine green fluorescent imaging. Quantitative analysis of indocyanine green fluorescent imaging may help prevent anastomotic complications during robot-assisted sphincter-saving operations, and may be of particular value in high-class ASA patients, older patients, and patients with a short descending mesocolon.

Prognostic value of perfusion CT in HCC treatment with sorafenib

To investigate the impact of sorafenib-treatment on intralesional perfusion using volume perfusion computed tomografy (VPCT) in hepatocellular carcinoma (HCC), correlate the observed changes to mRECIST at mid-term for identification of their prognostic value and document potential correlations with the course of serum alpha-fetoprotein (AFP).

Perioperative Changes in Cerebral Perfusion Territories Assessed by Arterial Spin Labeling Magnetic Resonance Imaging Are Associated with Postoperative Increases in Cerebral Blood Flow in Patients with Carotid Stenosis

The magnetic resonance imaging technique known as territorial arterial spin labeling (TASL) allows for noninvasive visualization of perfusion territories. The objective of this study was to use TASL to assess the relationship between perioperative changes in the perfusion territories of the internal carotid artery (ICA) and cerebral blood flow (CBF) after carotid revascularization. In 32 patients, ICA perfusion volume (PV) and CBF were measured before and after carotid endarterectomy/carotid artery stenting using TASL and single-photon emission computed tomography, respectively. ICA flow was measured during carotid endarterectomy before and after reconstruction, using an electromagnetic flowmeter. Eleven healthy volunteers, as the normal control group, underwent TASL evaluation. We classified patients into 2 groups: the normal PV group (ICA PV ≥ mean-2 standard deviation of healthy volunteers; n= 13) and the reduced PV group (ICA PV < mean-2 standard deviation; n= 19). The postoperative increase in the ICA PV and CBF were significantly greater in the reduced PV group than in the normal group (90.4% ± 131.8% vs. 10.5 ± 9.8%, P= 0.017, 32.0±25.7% vs. 10.5% ± 10.7%, P= 0.0032, respectively). ICA flow increased significantly after reconstruction in both the normal PV group (115.1 ± 48.1 mL/minute to 159.1± 53 mL/minute; P= 0.016) and reduced PV group (57.8 ± 38.3 mL/minute to 182.3 ± 52.6 mL/minute; P<0.0001). However, in some patients in the reduced PV group, the PV increased only slightly, whereas the ICA flow markedly increased, which resulted in a large CBF increase, such as hyperperfusion. The TASL study suggested that an imbalance between increases in the PV and ICA flow could play an important role in the pathophysiology underlying postoperative abnormal increases in CBF.

Characteristics of CT Perfusion Parameters of Focal Pancreatic Lesions and Data Comparison of Different Algorithms.

Objective To characterize the CT perfusion parameters of focal pancreatic lesions including pancreatic cancers (PACs) and pancreatic neuroendocrine tumors (pNETs),estimate the confirmity and fungibility of parameters obtained from Deconvolution and Maximum slope+Patlak.Methods From December 2015 to November 2016,22 patients with PACs and 22 patients with pNETs(37 lesions confirmed by surgery and biopsy)underwent preoperative whole-pancreas CT perfusion in our center. The volume perfusion CT of the entire pancreas was performed at 80 kV and 100 mA,using 28 consecutive volume measurements and intravenous injection of 45 ml of iodinated contrast and saline at a flow rate of 5 ml/s. One experienced radiologists measured and recorded the CT perfusion parameters on Siemens post-processing workstation using two mathematical methods:Maximum slope+Patlak analysis versus Deconvolution method.ResultsWilcoxon matched-pairs test revealed significant difference between both pairs of the perfusion measurements by the two methods,PACs(BFM vs. BFD,Z=-3.263,P=0.001;BVD vs. BVP,Z=-3.978,P=0.000); pNETs(BFM vs. BFD,Z=-5.212,P=0.000;BVD vs. BVP,Z=-2.633,P=0.008). Spearman's correlation coefficient showed both pairs of perfusion measurements significantly correlated with each other in PACs (BFM vs. BFD,r=0.845,P=0.000;BVD vs. BVP,r=0.964,P=0.000) and pNETs(BFM vs. BFD,r=0.759,P=0.000),BVD vs. BVP,r=0.683,P=0.000). Geometric mean BFM/BFD ratio in PACs was 0.77 (range:0.61-0.99),while geometric mean BVD/BVP ratio was 1.42 (range:1.13-1.79),within 95% limits of agreement. Geometric mean BFM/BFD ratio in pNETs was 0.66 (range:0.51-0.86),while geometric mean BVD/BVP ratio was 1.15 (range:0.88-1.50),within 95% limits of agreement. Conclusion sSignificantly different CT perfusion values of blood flow and blood volume were obtained by Deconvolution-based and Maximum slope+Patlak-based algorithms in the pNETs and PACs. They correlated significantly with each other. Two perfusion-measuring algorithms are interchangeable because the ranges of the conversion factors are narrow.

Comparison between acoustic radiation force impulse quantification data and perfusion-CT parameters in hepatocellular carcinoma

ObjectiveTo find out, if ultrasound elastography of hepatocellular carcinoma (HCC) can predict patterns of tumor perfusion in volume perfusion computed tomography (VPCT). Material and methods25 consecutive patients (mean age, 68.9; range, 51–85 years) with liver cirrhosis suspected of HCC underwent VPCT and acoustic radiation force impulse (ARFI) elastography the same day. Quantitative elasticity values were registered, while blood flow (BF), blood volume (BV) and hepatic perfusion index (HPI) of the HCC lesions were calculated. Additionally, we identified histologic WHO grading, lesion size and localization. The Siemens Acuson S 3000 HELX-System with Virtual Touch™-Software and Siemens Somatom Definition Flash with Syngo® software were used. ResultsA total of 43 HCC lesions were assessed. Mean shear wave velocity was 2.6m/s (range, 1.1–4.3m/s). There was no significant linear correlation between the elasticity values and BF (p=0.751), BV (p=0.426) and HPI (p=0.437). However, elasticity values were higher, the larger the tumor was (p=0.008). Shear wave velocity declined with increasing distance of the HCC to the skin surface (p=0.028) and depending on liver segment. In addition, elasticity values were higher in less differentiated HCCs. This trend was not statistically significant (p=0.842). ConclusionTissue elasticity in HCC does not correlate with the degree of tumor vascularization, but calculated values are influenced both by the tumor size and localization inside the liver.

Perioperative application of salvianolate on oxidative stress and plasma IMD/ADM2 in patients with acute myocardial infarction undergoing PCI.

The present study was conducted to investigate the effects of salvianolate on perioperative oxidative stress and plasma Intermedin/adrenomedullin 2 (IMD/ADM2) in patients with acute myocardial infarction (AMI) undergoing percutaneous coronary intervention (PCI). The clinical data of 108 patients with AMI treated by PCI were retrospectively analyzed. According to the use of salvianolate in perioperative period, the patients were divided into the study group (n=62) and the control group (n=46). The control group was given routine treatment while the study group was given routine treatment combined with intravenous infusion of salvianolate (200 mg administered once at 24 h before operation, once/day after operation, 1 week later, the curative effect was observed). The changes in levels of hemodynamic indexes [fibrinogen (FIB), platelet aggregation rate (PAG), plasma viscosity, packed-cell volume (PCV)], oxidative stress indexes [superoxide dismutase (SOD), glutathione peroxidase (GSH Px)], cardiac function indexes [left ventricular ejection fraction (LVEF), cardiac output (CO)], related biochemical indexes [high-sensitivity C-reactive protein (hs-CRP), N-terminal pro brain natriuretic peptide (NT proBNP)] and plasma IMD/ADM2 in the two groups at 24 h pre-operation and the 8th day postoperation were analyzed. On the 8th day post-operation, hemodynamic indexes such as FIB (3.3±1.0 and 3.9±0.9) g/l, PAG (20.6±6.5 and 41.6±7.7)%, plasma viscosity (1.1±0.5 and 1.7±0.6) mPa•s/120 s−1 and PCV (40.0±3.8 and 45.5±3.7)%, the related biochemical indexes such as hs-CRP (55.1±4.8 and 79.3±5.3) mg/l and NT-proBNP (435.6±305.2 and 788.6±310.8) ng/l in the two groups were significantly decreased compared to those pre-operation; the differences were statistically significant (P<0.05). The oxidative stress indexes such as SOD (43.6±1.9 and 24.2±2.0) U/ml and GSH-Px (822.6±13.52 and 742.6±62.6) enzyme activity unit, the cardiac function indexes such as LVEF (45.1±3.5 and 41.9±3.3)% and CO (4.6±0.5 and 4.1±0.5) l/min and plasma IMD/ADM2 (163.5±20.2 and 144.2±22.5) pg/ml in the two groups were significantly increased compared to those pre-operation; the differences were statistically significant (P<0.05). In conclusion, applying intravenous infusion of salvianolate in patients with AMI during perioperative period of PCI can effectively improve the oxidative stress reaction and have positive effects on regulating plasma IMD/ADM2 level, which promoted cardiac function recovery and enhances myocardial perfusion volume.

Multiparametric Imaging of Tumor Hypoxia and Perfusion with 18F-Fluoromisonidazole Dynamic PET in Head and Neck Cancer.

Tumor hypoxia and perfusion are independent prognostic indicators of patient outcome. We developed the methodology for and investigated the utility of multiparametric imaging of tumor hypoxia and perfusion with 18F-fluoromisonidazole (18F-FMISO) dynamic PET (dPET) in head and neck cancer. Methods: One hundred twenty head and neck cancer patients underwent 0- to 30-min 18F-FMISO dPET in a customized immobilization mask, followed by 10-min static acquisitions starting at 93 ± 6 and 160 ± 13 min after injection. A total of 248 lesions (≥2 cm3) were analyzed. Voxelwise pharmacokinetic modeling was conducted using an irreversible 1-plasma 2-tissue-compartment model to calculate surrogate biomarkers of tumor hypoxia (k3), perfusion (K1), and 18F-FMISO distribution volume. The analysis was repeated with truncated dPET datasets. Results: Substantial inter- and intratumor heterogeneity was observed for all investigated metrics. Equilibration between the blood and unbound 18F-FMISO was rapid in all tumors. 18F-FMISO distribution volume deviated from the expected value of unity, causing discrepancy between k3 maps and total 18F-FMISO uptake and reducing the dynamic range of total 18F-FMISO uptake for quantifying the degree of hypoxia. Both positive and negative trends between hypoxia and perfusion were observed in individual lesions. All investigated metrics were reproducible when calculated from a truncated 20-min dataset. Conclusion:18F-FMISO dPET provides the data necessary to generate parametric maps of tumor hypoxia, perfusion, and radiotracer distribution volume. These data clarify the ambiguity in interpreting 18F-FMISO uptake and improve the characterization of lesions. We show total acquisition times can be reduced to 20 min, facilitating the translation of 18F-FMISO dPET into the clinic.

Abstract TP116: Perioperative Assessment of Cerebral Perfusion Territories Through Arterial Spin Labeling Magnetic Resonance Imaging in Carotid Stenosis

Backgroud: Territorial arterial spin labeling (TASL) is a MRI technique that permits independent labeling of major individual feeding vessels and noninvasive visualization of their perfusion territories. Objective: The objectives of this study were to use TASL to assess perioperative changes in the perfusion territories of the internal carotid arteries (ICAs) in carotid stenosis patients and to investigate the usefulness of this technique. Methods: Thirty-two patients underwent TASL and SPECT before and after carotid endarterectomy (CEA) or carotid artery stenting (CAS). ICA perfusion volume was calculated using TASL images. ICA flow was measured during CEA, both before and after reconstruction, using electromagnetic flow meter. Results: In most cases, preoperative asymmetry ( Fig. A ) of ICA perfusion volume improved postoperatively ( Fig B ) (red, rt ICA; green, lt ICA; blue, VA-BA). We classified patients into the following two groups: (1) an elevated CBF group (CBF increase after surgery ≥50%, n=4) and (2) a stable CBF group (CBF increase after surgery &lt;50%, n=28). ICA perfusion volume increased significantly after surgery in the stable CBF group (291.1±89.0cm 3 versus 396.4±40.9cm 3 , p&lt;0.0001) but did not increase significantly in the elevated CBF group (246.4±103.2cm 3 versus 268.7±107.7cm 3 ) ( Fig. C ). However, ICA flow increased significantly after reconstruction in both the elevated CBF group (54.0±58.2ml/min → 177.7±25.4ml/min) and the stable CBF group (85.7±50.0ml/min → 171.8±56.1ml/min) (p&lt;0.0001) ( Fig. D ). Conclusion: TASL clearly demonstrated that CEA and CAS elicited increases in the perfusion volumes of stenotic ICAs, which resulted in equalization of the perfusion volumes of the left and right ICA. In the elevated CBF group, however, ICA perfusion volume increased slightly, despite marked increase in ICA flow. These findings suggest that an imbalance between these parameters plays an important role in the pathophysiology of hyperperfusion.

Sporadic insulinomas on volume perfusion CT: dynamic enhancement patterns and timing of optimal tumour-parenchyma contrast.

To assess enhancement patterns of sporadic insulinomas on volume perfusion CT (VPCT), and to identify timing of optimal tumour-parenchyma contrast. Consecutive patients who underwent VPCT for clinically suspected insulinomas were retrospectively identified. Patients with insulinomas confirmed by surgery were included, and patients with familial syndromes were excluded. Two radiologists evaluated VPCT images in consensus. Tumour-parenchyma contrast at each time point was measured, and timing of optimal contrast was determined. Time duration of hyperenhancement (tumour-parenchyma contrast >20 Hounsfield units, HU) was recorded. Perfusion parameters were evaluated. Three dynamic enhancement patterns were observed in 63 tumours: persistent hyperenhancement (hyperenhancement time window ≥10s) in 39 (61.9%), transient hyperenhancement (hyperenhancement <10s) in 19 (30.2%) and non-hyperenhancement in 5 (7.9%). Timing of optimal contrast was 9s after abdominal aorta threshold (AAT) of 200 HU, with tumour-parenchyma contrast of 77.6 ± 57.2 HU. At 9s after AAT, 14 (22.2%) tumours were non-hyperenhancing, nine of which had missed transient hyperenhancement. Insulinomas with transient and persistent hyperenhancement patterns had significantly increased perfusion. Insulinomas have variable enhancement patterns. Tumour-parenchyma contrast is time-dependent. Optimal timing of enhancement is 9s after AAT. VPCT enables tumour detection even if the hyperenhancement is transient. • Enhancement patterns of insulinomas are variable and tumour-parenchyma contrast is time-dependent. • An optimized single-phase scan found 77.8% tumours to be hyperenhancing. • Hyperenhancing tumours increase to 84.1% and 87.3% with biphasic/triphasic scan. • Volume perfusion CT enables detection of insulinomas with missed transient hyperenhancement.

Impact of transjugular intrahepatic portosystemic shunt implantation on liver perfusion measured by volume perfusion CT.

Background Implantation of a transjugular intrahepatic portosystemic shunt (TIPS) induces changes of liver perfusion. Purpose To determine the changes in arterial, portal venous, and total perfusion of the liver parenchyma induced by TIPS using the technique of volume perfusion computed tomography (VPCT) and compare results with invasively measured hepatic intravascular pressure values. Material and Methods VPCT quantification of liver perfusion was performed in 23 patients (mean age, 62.5 ± 8.8 years) with portal hypertension in the pre-TIPS and post-TIPS setting, respectively. A commercially available software package was used for post-processing, enabling separate calculation of the dual (arterial [ALP] and portal venous [PVP]) blood supply and additionally of the hepatic perfusion index (HPI) (HPI = ALP/(ALP + PVP)*100%). Invasive pressure measurements were performed during the intervention, before and after TIPS placement. Liver function tests performed before and after the procedure were compared. Results Mean decrease of pressure gradient through TIPS was 13.3 mmHg. Mean normal values for ALP, PVP, and total perfusion (ALP + PVP) before TIPS were 15.9, 37.7, and 53.5 mL/100 mL/min, respectively, mean HPI was 35.4%. After TIPS, ALP increased to a mean value of 37.7 mL/100 mL/min, PVP decreased (15.7 mL/100 mL/min, P < 0.05), whereas total perfusion remained unchanged (53.4 mL/100 mL/min, P = 0.97). HPI increased (71.9%; P < 0.05). No correlation between invasive pressure measurement and VPCT parameters was observed. After TIPS, liver function tests were found to worsen with a significant increase of bilirubin ( P < 0.05). Conclusion Following TIPS placement, ALP and HPI increased in all patients, whereas PVP markedly decreased. Interestingly, the magnitude of decrease in portosystemic pressure gradients was not found to correlate with VPCT parameters.

Early Changes in Contrast Enhanced Ultrasound Predict for Pathologic Response to Chemotherapy in an Animal Tumor Model

The purpose of this study was to examine CEUS whether could earlier predict pathologic response to chemotherapy than morphologic method in a MCF-7 tumor model. Twenty MCF-7 breast cancer bearing nude mice were included in this study. Animals received either adriamycin or a control substance were imaged before and after treatment with an ultrasound scanner after bolus injection of SonoVue. Dynamic contrast enhanced ultrasound was performed at pretherapy, Day 3, Day 5 and Day 7 after adriamycin administration. Regions of interest within the tumor were analyzed off-line to determine perfusion parameters including peak enhancement (PE), area under the curve of wash-in (WIAUC), wash-in rate (WIR), wash-in perfusion index (WIPI) and quality of fit (QOF). The section equivalent to ultrasound imaging plane was stained with Hematoxylin and Eosin to allow for assessment of tumor cell density and Ki67 for situation of tumor proliferation, CD34 for tumor micro-vascular density. There were no significant differences in tumors perfusion and tumor volumes before treatment. Treatment with adriamycin resulted into a significant decrease in PE, WIAUC, WIR and WIPI in comparison with control group (P < 0.05) at Day 3, when there was no significant difference in tumor volume. The volume of treated tumors was significant smaller than that of control tumors (P < 0.05) at day 7. The tumor cell density estimated by pathology slice was significantly lower in treated tumors than in control tumors at day 7 (P < 0.05). The positive Ki67 cell density and CD34 estimated by pathology slice were also significantly lower in treated tumors than in control tumors at day 7 (P < 0.05). The correlation between micro-vascular and perfusion parameters was obvious (P < 0.05). Changes in tumor micro-vessel functionality as depicted by CEUS early on after starting adriamycin -based chemotherapy can predict final pathologic response. Contrast enhanced ultrasound will be a new way for evaluating tumor response to chemoth.

Simultaneous investigation of microvasculature and parenchyma in cerebral small vessel disease using intravoxel incoherent motion imaging.

IntroductionCerebral small vessel disease (cSVD) is associated with microvascular and parenchymal alterations. Intravoxel incoherent motion (IVIM) MRI has been proposed to simultaneously measure both the microvascular perfusion and parenchymal diffusivity. This study aimed to evaluate the application of IVIM in cSVD to assess the microvasculature and parenchymal microstructure.MethodsSeventy-three patients with cSVD (age 70 ± 11 y) and thirty-nine controls (age 69 ± 12 y) underwent IVIM imaging (3T). Group differences of the perfusion volume fraction f and the parenchymal diffusivity D were investigated using multivariable linear regression accounted for age, sex and cardiovascular factors. To examine the relation between the IVIM measures and the disease severity on structural MRI, white matter hyperintensity (WMH) load served as surrogate measure of the disease severity.ResultsPatients had a larger f (p < 0.024) in the normal appearing white matter (NAWM) than controls. Higher D (p < 0.031) was also observed for patients compared with controls in the NAWM and grey matter. Both f (p < 0.024) and D (p < 0.001) in the NAWM and grey matter increased with WMH load.ConclusionsThe increased diffusivity reflects the predicted microstructural tissue impairment in cSVD. Unexpectedly, an increased perfusion volume fraction was observed in patients. Future studies are needed to reveal the precise nature of the increased perfusion volume fraction. IVIM imaging showed that the increases of f and D in cSVD were both related to disease severity, which suggests the potential of IVIM imaging to provide a surrogate marker for the progression of cSVD.

P2.03b-002 Efficacy and Safety of WBRT Combined with Endostar in Patients with Advanced Non-Small Cell Lung Cancer: Topic: Brain Meta

We aimed to identify the optimal regimen of endostar combined with whole brain irradiation(WBRT) for BM for evaluation and provide preliminary efficacy data. The 30 cases of advanced NSCLC patients with symptomatic unresectable BM were randomly divided into two groups, experimental group (15 cases): the Endostar (15 mg/m2, intravenous infusion, d1-7) synchronization of WBRT (40 Gy/20 fractions/4 weeks); control group (15 cases): WBRT alone. Cerebral blood volume (CBV), blood flow (CBF) and mean perfusion time (MTT) and lymphocyte analysis were observed by magnetic resonance perfusion imaging before and 4 weeks after WBRT. In experimental group, CBF, CBV and MTT at baseline were 582.12±161.42, 524.00±428.64 and 235.00±149.36. Four weeks after treatment, those perfusion values were 260.00±356.6, 336.00±480.82 and 509.00±44.34 respectively, which showed obvious decreasing trends compared with baseline data in CBF and CBV, while increased in MTT(Fig 1).Figure 2Immune function related indicators. All the ten cases showed a partial response (PR) to therapy in experimental group, while in the control group the response rate was 40%.Endostar in combination with WBRT was generally well tolerated.View Large Image Figure ViewerDownload Hi-res image Download (PPT) Endostar combined with WBRT appears to be a efficacy and tolerable treatment of BM.

Benign Oligemia in Subacute Stage Is Associated with Borderzone Infarction in Stroke Patients Caused by Intracranial Large Artery Disease

Background: CT perfusion (CTP) imaging provides quantitative evaluation of cerebral perfusion flow and volume. Our previous findings showed that benign oligemia caused by intracranial large artery disease may be existent in subacute stroke. Aims: We aimed at comparing the topographic patterns and clinical outcome of stroke patients with and without persistent benign oligemia as defined by CTP imaging. Methods: Consecutive ischemic stroke patients who were referred for CTP in 2009 were screened. The topographic patterns (cortical, borderzone or perforating artery territory infarcts) were assessed by diffusion-weighted imaging (DWI). The clinical outcome was defined by modified Rankin score at 6 months after stroke onset. Results: Totally, 26 stroke patients were recruited. Benign oligemia in subacute stage was detected in 15 patients. The occurrence of borderzone infarction was higher in stroke patients with benign oligemia than those without (p = 0.036). Conclusions: The topographic pattern of DWI may be different between the intracranial arterial disease patients with and without benign oligemia on CTP in subacute stroke.