Associations Between Carotid Plaque Characteristics and Improvement of Cerebral Blood Perfusion in Patients With Moderate to Severe Carotid Stenosis Undergoing Carotid Endarterectomy

BACKGROUND

The relationship between plaque characteristics and their predictive value for perioperative cerebral blood flow (CBF) are unknown.

PURPOSE

To investigate the relationship between carotid plaque characteristics and perioperative CBF utilizing MRI.

STUDY TYPE

Prospective.

POPULATION

In all, 131 patients with carotid moderate-to-severe stenosis referred for carotid endarterectomy (CEA).

FIELD STRENGTH/SEQUENCE

3T, black-blood T₁ - and T₂ -weighted, 3D time-of-flight, and simultaneous noncontrast angiography intraplaque hemorrhage.

ASSESSMENT

The relative CBF (rCBF = CBF_{index-hemisphere} /CBF_{contralateral-hemisphere} ) and the CBF difference ratio (DR_CBF = [CBF_post-CEA - CBF_pre-CEA ]/CBF_pre-CEA ) in the middle cerebral artery territory were measured. The pre- and post-CEA CTP data were used as the assessment standard for CBF change. Carotid lipid-rich necrotic core (LRNC), intraplaque hemorrhage, calcification, fibrous cap rupture, maximum wall thickness, normalized wall index (NWI), and stenosis were determined.

STATISTICAL TESTS

Pearson or Spearman correlation, Mann-Whitney U-test, and linear regression.

RESULTS

Patients with LRNC had higher rCBF_pre-CEA than those without (1.0 ± 0.1 vs. 0.9 ± 0.1, P < 0.05). NWI was weakly correlated with rCBF_pre-CEA (r = -0.213, P < 0.05) and DR_CBF (r = 0.185, P < 0.05) and marginally correlated with rCBF_post-CEA (r = 0.166, P = 0.057). LRNC was weakly correlated with rCBF_pre-CEA (r = 0.179, P < 0.05). NWI was associated with rCBF_pre-CEA (β = -0.035; 95% confidence interval [CI] [-0.064, -0.006]; P < 0.05), rCBF_post-CEA (β = 0.042; 95% CI [0.002, 0.081]; P < 0.05) and DR_CBF (β = 0.105; 95% CI [0.026, 0.185]; P < 0.05). After adjusting for confounding factors, associations of NWI with rCBF_post-CEA (β = 0.059; 95% CI [0.016, 0.103]; P < 0.05) and DR_CBF (β = 0.110; 95% CI [0.021, 0.199]; P < 0.05) remained statistically significant, while the association between NWI and rCBF_pre-CEA was no longer significant (β = -0.026; 95% CI [-0.058, 0.006]; P = 0.112).The associations of LRNC with rCBF_pre-CEA (β = 0.057; 95% CI [-0.0006, 0.114]; P = 0.052) and DR_CBF (β = -0.157; 95% CI [-0.314, 0.001]; P = 0.051) were close to statistical significance. After adjusting for confounding factors, these associations were statistically significant (of LRNC vs. rCBF_pre-CEA : β = 0.060; 95% CI [0.003, 0.118]; P < 0.05; LRNC vs. DR_CBF : β = -0.205; 95% CI [-0.375, -0.036]; P < 0.05).

DATA CONCLUSION

Carotid plaque burden and components, particularly LRNC, might be effective indicators for CBF change following CEA. Level of Evidence 1 Technical Efficacy Stage 5.

Quantitative evaluation of carotid atherosclerotic vulnerable plaques using in vivo T1 mapping cardiovascular magnetic resonaonce: validation by histology

BACKGROUND

It has been proved that multi-contrast cardiovascular magnetic resonance (CMR) vessel wall imaging could be used to characterize carotid vulnerable plaque components according to the signal intensity on different contrast images. The signal intensity of plaque components is mainly dependent on the values of T1 and T2 relaxation. T1 mapping recently showed a potential in identifying plaque components but it is not well validated by histology. This study aimed to validate the usefulness of in vivo T1 mapping in assessing carotid vulnerable plaque components by histology.

METHODS

Thirty-four subjects (mean age, 64.0 ± 8.9 years; 26 males) with carotid plaques referred to carotid endarterectomy were prospectively enrolled and underwent 3 T CMR imaging from May 2017 to October 2017. The T1 values of intraplaque hemorrhage (IPH), necrotic core (NC) and loose matrix (LM) which were identified on multi-contrast vessel wall images or histology were measured on in-vivo T1 mapping. The IPHs were divided into two types based on the proportion of the area of fresh hemorrhage on histology. The T1 values of different plaque components were compared using Mann-Whitney U test and the agreement between T1 mapping and histology in identifying and quantifying IPH was analyzed with Cohen's Kappa and intraclass correlation coefficient (ICC).

RESULTS

Of 34 subjects, 19 had histological specimens matched with CMR imaging. The mean T1 values of IPH (651 ± 253 ms), NC (1161 ± 182 ms) and LM (1447 ± 310 ms) identified by histology were significantly different. The T1 values of Type 1 IPH were significantly shorter than that of Type 2 IPH (456 ± 193 ms vs. 775 ± 205 ms, p < 0.001). Moderate to excellent agreement was found in identification (kappa = 0.51, p < 0.001), classification (kappa = 0.40, p = 0.028) and segmentation (ICC = 0.816, 95% CI 0.679-0.894) of IPHs between T1 mapping and histology.

CONCLUSIONS

The T1 values of carotid plaque components, particularly for intraplaque hemorrhage, are differentiable, and the stage of intraplaque hemorrhage can be classified according to T1 values, suggesting the potential capability of assessment of vulnerable plaque components by T1 mapping.

Quantitative assessment of carotid artery atherosclerosis by three-dimensional magnetic resonance and two-dimensional ultrasound imaging: a comparison study

Background

It has been proven that magnetic resonance (MR) and ultrasound imaging are useful tools in the quantification of carotid atherosclerotic plaques. However, there are only a few pieces of evidence to illustrate the links of quantitative measurements of carotid plaques between MR and ultrasound imaging. This study looked to compare the quantitative measurements of carotid plaques and investigate their relationship between three-dimensional (3D) MR vessel wall imaging and two-dimensional (2D) ultrasound imaging.

Methods

Seventy-five asymptomatic elderly subjects (mean age: 73.3±5.7 years; 45 males) with carotid atherosclerotic plaques diagnosed by both ultrasound and MR imaging were included in this study. The plaque size, including the maximum wall thickness (Max WT), plaque length, and plaque area, was measured by 3D MR and ultrasound imaging on longitudinal and cross-sectional views. The quantitative assessments of carotid plaque size were compared and correlated between 3D MR and 2D ultrasound imaging.

Results

In total, the quantitative measurements of 101 plaques on longitudinal views or 44 plaques on cross-sectional views of both MR and ultrasound imaging were compared. The Max WT of the plaques (longitudinal: 2.9±0.8 vs. 2.4±0.9 mm; cross-sectional: 3.2±1.1 vs. 2.6±0.7 mm) and plaque areas (longitudinal: 24.3±13.4 vs. 17.0±12.7 mm²; cross-sectional: 24.9±24.6 vs. 16.8±13.3 mm²) measured by MR imaging were found to be significantly higher than those measured by ultrasound imaging (all P<0.001). Moderate to strong correlations were found in Max WT, plaque area, plaque length between 3D MR and ultrasound imaging.

Conclusions

The quantitative measurements of carotid plaques using 3D MR and 2D ultrasound are significantly correlated. The plaque area and Max WT measured by 3D MR imaging are more significant than these parameters measured by 2D ultrasound imaging, which might be explained by the resolution of MR imaging and the workflow of measurements.

One-day protocol for 18F-FDG and 13N-ammonia PET/CT with uptake decoupling score in differentiating untreated low-grade glioma from inflammation

PURPOSE

Accurate identification of low-grade gliomas (LGGs; World Health Organization grades I and II) and their differentiation from brain inflammation lesions (BILs) remains difficult; however, it is essential for treatment. This study assessed whether a one-day protocol for voxel-wise ¹⁸F-FDG and ¹³N-ammonia PET/CT with uptake decoupling analysis could differentiate LGGs from BILs.

MATERIALS AND METHODS

Twenty-eight patients with LGGs and 16 patients with BILs underwent ¹⁸F-FDG and ¹³N-ammonia PET/CT on the same day before any type of therapy. The decoupling score and tumor-to-normal tissue (T/N) ratio of ¹⁸F-FDG and ¹³N-ammonia were calculated at each location. Student's t-test was used to compare values, and ROC curve analysis was used to establish a cut-off value for the T/N ratio and decoupling score. Area under the curve (AUC) was calculated to evaluate differential efficacy.

RESULTS

Significant differences were observed in ¹³N-ammonia T/N ratio (p=0.018) and decoupling score (p=0.003) between LGGs and BILs; however, the ¹⁸F-FDG T/N ratio did not show any differences (p=0.413). Optimal cut-off values for ¹⁸F-FDG T/N ratio, ¹³N-ammonia T/N ratio, and decoupling score were 0.73, 0.97, and 2.31, respectively, with corresponding AUCs of 0.48, 0.68, and 0.77. The respective sensitivity, specificity, and accuracy parameters using these cut-off values were 53.6%, 62.5%, and 56.8%, respectively, for ¹⁸F-FDG; 50.0%, 75.0%, and 59.1%, respectively, for ¹³N-ammonia; and 60.7%, 93.8%, and 72.7%, respectively, for decoupling score.

CONCLUSIONS

¹⁸F-FDG/¹³N-ammonia uptake decoupling score can be used to discriminate between LGGs and BILs. Use of a decoupling map of these two tracers can improve visual analysis and diagnostic accuracy.

Correction to: Segment-specific progression of carotid artery atherosclerosis: a magnetic resonance vessel wall imaging study

The above article was published online with incorrect presentation of author name. Mingming is the given name and Lu is the family name. The presentation of the author name has been corrected above.

[Determination of seven urinary metabolites of benzene, toluene and xylene by ultra-high performance liquid chromatography-triple quadrupole mass spectrometry]

Objective: To develop a method using ultra-high performance liquid chromatography-triple quadrupole mass spectrometry to determine the urinary metabolites of benzene, toluene and xylene. The selected metabolites are S-phenylmercapturic acid (S-PMA) , trans, trans-muconic acid (t, t-MA) , 8-hydroxy-2 deoxyguanosine (8-OHdG) , hippuric acid (HA) , 2-methylhippuric acid (2-MHA) , 3-methylhippuric acid (3-MHA) and 4-methylhippuric acid (4-MHA) . Methods: The urine sample was pretreated using methanol to precipitate the proteins. HSS T3 chromatographic column was used to separate the metabolites. The mass spectrometric acquisition was carried out using multiple reaction monitoring (MRM) after ionization with ESI source. External standard method was used for quantification. Results: All the standard curves showed good linear relation, and r of the seven metabolites was all above 0.999. The detection limits and quantitative limits of the seven metabolites were 0.01-500 ng/ml and 0.02-1 000 ng/ml (based on the actual dilution ratio) , respectively. The average spiked recoveries of four loadings ranged from 85.8% to 109.9%. The intra-day and inter-day precisions were 0.2%-4.5% and 0.6%-9.5%, respectively. The samples can be kept for at least 14 days at both 4 ℃ and -20 ℃. Conclusion: This method is simple, rapid and highly sensitive with low cost, and its accuracy, precision and stability can meet the daily test requirements. It can be applied for the determination of urinary S-PMA, t, t-MA, 8-OHdG, HA, 2-MHA, 3-MHA and 4-MHA for the occupational population exposed to benzene, toluene and xylene.

[Determination of Cortisol in Saliva by Liquid Chromatography Tandem Mass Spectrometry]

Objective: To establish a liquid chromatography tandem mass spectrometry method to determine the cortisol in saliva. Methods: Take 0.5 ml saliva sample into a 2 ml centrifuge tube, add excess sodium chloride and 1ml acetonitrile to it, then vortex for 3 min, centrifuge for 10 min at 15 000 r/min, and take 800 μl of the upper layer to another centrifuge tube. Finally, the sample was concentrated by a vacuum concentrator and brought to 200 μl with the initial mobile phase. Then, the sample was analyzed by liquid chromatography tandem mass spectrometry. The target compound was quantified by external standard curve method. Results: The linear range of the method was 0.02-5.00 ng/ml, r=0.999 9, the method limit of the detection was 0.002 ng/ml, the method limit of quantitative was 0.02 ng/ml, and the spiked recoveries were 89.60%-98.60%. The intra-assay precision was 1.90%-3.30%, and the inter-assay precision was 4.20%-9.00%; samples could be stored at -20 °C for at least 14 days. The determination of cortisol could not be interfered by other endogenous substances in the sample. Conclusion: The method is simple in pretreatment, high sensitivity, good reproducibility and good recovery, and it is suitable for the quantitative analysis of cortisol in saliva for normal and occupationally stressed populations.

Association between age and progression of carotid artery atherosclerosis: a serial high resolution magnetic resonance imaging study

This study aimed to investigate the association between age and progression of carotid atherosclerotic plaques using serial high resolution magnetic resonance imaging (MRI). Symptomatic patients who had carotid atherosclerosis with 30-70% stenosis were enrolled in this study. Carotid MRI was performed at baseline and follow-up time point (≥ 6 months after baseline), respectively. The characteristics of carotid plaque progression among different age groups (> 75 years old, 60-75 years old and < 60 years old) were compared. Logistic regression was performed to relate age with carotid plaque progression. Of recruited 84 patients, 73 (mean age, 66.5 ± 11.4 years old; males, 82.2%) with 96 plaques were included in the final analysis. Compared with younger patients, older ones had significantly higher incidence of calcification in carotid plaques (> 75 years old: 91.3%, 60-75 years old: 65.7% and < 60 years old: 55.3%, p = 0.013), greater annual change of carotid wall volume (> 75 years old: 39.0 (4.3-104.6) mm³, 60-75 years old: 28.7 (- 28.0 to 73.7) mm³ and < 60 years old: 4.8 (- 27.1-31.9) mm³, p = 0.032) and maximum carotid wall area (> 75 years old: 6.1 (- 3.5 to 17.2) mm², 60-75 years old: 2.4 (- 4.7 to 15.1) mm² and < 60 years old: 1.4 (- 5.8 to 6.9) mm², p = 0.046). Age (OR 1.44; 95% CI 1.10-1.89; p = 0.009) and hypertension (OR 4.61; 95% CI 1.41-15. 02; p = 0.011) were independent predictors in discriminating upper quartile of annual change of carotid wall volume after adjusting for all clinical factors. Older patients have faster progression rate in carotid plaques than younger ones and age is independently associated with carotid plaque progression. Our findings suggest that the carotid plaques of older patients need to be monitored more frequently.

Shape and Location of Carotid Atherosclerotic Plaque and Intraplaque Hemorrhage: A High-resolution Magnetic Resonance Imaging Study

Aim: The present study aimed to investigate the association between shape and location of atherosclerotic plaques and intraplaque hemorrhage (IPH) in carotid arteries using magnetic resonance (MR) imaging.

Methods: Overall, 114 symptomatic patients (mean age: 64.9±10.9 years; 81 males) who underwent MR imaging and had advanced carotid plaques were included in analysis. IPH presence and carotid plaque shape and location (below and above bifurcation) were evaluated. The plaque shape was defined as follows: type-I: the arc-length of plaque is greater in the upstream; type-II: the arc-length of plaque in downstream and upstream is equal; and type-III: the arc-length of plaque is greater in downstream. The plaque shape and location were compared between plaques with and without IPH and their associations with IPH were determined.

Results: Of 181detectedplaques, 57 (31.5%) had IPH. Compared with plaques without IPH, those with IPH had higher incidence of the plaque shape of type-I (66.7% vs. 32.2%, P<0.001), lower incidence of plaque shape of type-III (24.6% vs. 50.0%, P=0.001), and were more likely located above carotid bifurcation (71.9% vs. 48.4%, P=0.003). The plaque shape of type-I (OR, 4.01; 95%CI, 1.36–11.83; P=0.012) and location above bifurcation (OR, 3.21; 95%CI, 1.07–9.61; P=0.037) of carotid plaques were significantly associated with IPH after adjusting for confounder factors.

Conclusions: Carotid plaque shape and location are significantly associated with the occurrence of IPH. Our findings could provide new insights for the pathogenesis of IPH and vulnerably plaques.

Intracranial artery stenosis magnetic resonance imaging aetiology and progression study: Rationale and design

BACKGROUND

It has been shown that intracranial artery stenosis (ICAS) plays a key role in Chinese ischemic stroke or transient ischemic attack (TIA) patients. Many vascular diseases can lead to ICAS, such as atherosclerosis, dissection, vasculitis, moyamoya disease, and reversible cerebral vasoconstriction syndrome (RCVS). In addition, progression of intracranial atherosclerotic disease (ICAD) will increase the risk of ischemic cerebrovascular events. The ICASMAP study primarily aims to determine the etiology and disease distribution of ICAS using noninvasive magnetic resonance (MR) imaging and evaluate the rate for progression of ICAD in symptomatic population.

METHODS

The ICASMAP study is a prospective, observational, and multicenter study by recruiting 300 subjects (18-80 years old) with recent stroke or TIA (within 2 weeks after onset of symptoms) in China. All the subjects will undergo MR imaging examination including brain and intracranial artery MR imaging at baseline. In addition, the clinical risk factors will be collected and blood biomarkers will be tested. A subgroup of more than 200 subjects who were diagnosed with ICAD according to baseline MR imaging will be followed up for 2 years. During the follow-up study, MR imaging examination will be performed at 12 and 24 months. The primary end point is presence of progression of intracranial artery atherosclerotic plaques.

CONCLUSIONS

The ICASMAP study investigates the etiology of ICAS and progression of ICAD in Chinese stroke patients and may help to improve the precise diagnosis and intervention of ICAS and stroke prevention.

PROPERTIES OF THERMOLUMINESCENT CARDS WITH HIGH SENSITIVE GR-200A LiF:Mg,Cu, P DETECTORS FOR HARSHAW AUTOMATIC READER

New DML TL cards with GR-200A detectors were developed. The TL sensitivity remains stable and the detectors were sealed firmly during the encapsulation process. The sensitivity, detection threshold, residual signal, reusability, dose response and Teflon capsule resistance of DML cards with two GR-200A detectors with diameter 3.6 mm and thickness 0.38 mm placed in positions 2 and 3 were evaluated. The detection thresholds were 0.61 μSv for the detector at position 2 and 1.15 μSv for the detector at position 3. The residual signals were 0.40% for the detector at position 2 and 0.57% for the detector at position 3. The 10 repeated readings of the same 10 irradiated cards were found within 1% for the two detectors on the cards. The DML cards demonstrate very high sensitivity, low background and good stability and can be used for very low dose ranges in personnel dosimetry and in environmental monitoring.

Simultaneous T1 and T2 mapping of the carotid plaque (SIMPLE) with T2 and inversion recovery prepared 3D radial imaging

PURPOSE

To propose a technique that can produce different T₁ and T₂ contrasts in a single scan for simultaneous T₁ and T₂ mapping of the carotid plaque (SIMPLE).

METHODS

An interleaved 3D golden angle radial trajectory was used in conjunction with T₂ preparation with variable duration (TE_prep ) and inversion recovery pulses. Sliding window reconstruction was adopted to reconstruct images at different inversion delay time and TE_prep for joint T₁ and T₂ fitting. In the fitting procedure, a rapid B₁ correction method was presented. The accuracy of SIMPLE was investigated in phantom experiments. In vivo scans were performed on 5 healthy volunteers with 2 scans each, and on 5 patients with carotid atherosclerosis.

RESULTS

The phantom T₁ and T₂ estimations of SIMPLE agreed well with the standard methods with the percentage difference smaller than 7.1%. In vivo T₁ and T₂ for normal carotid vessel wall were 1213 ± 48.3 ms and 51.1 ± 1.7 ms, with good interscan repeatability. Alternations of T₁ and T₂ in plaque regions were in agreement with the conventional multicontrast imaging findings.

CONCLUSION

The proposed SIMPLE allows simultaneous T₁ and T₂ mapping of the carotid artery in less than 10 minutes, serving as a quantitative tool with good accuracy and reproducibility for plaque characterization.

Association of Age and Size of Carotid Artery Intraplaque Hemorrhage and Minor Fibrous Cap Disruption: A High Resolution Magnetic Resonance Imaging Study

Aim: To investigate the association between the volumes of different aging intraplaque hemorrhage (IPH) and minor fibrous cap disruption (MFCD) in carotid arteries.

Methods: Patients with cerebrovascular symptoms and carotid atherosclerotic plaques determined by ultrasound were recruited and underwent multi-contrast magnetic resonance (MR) vessel wall imaging for carotid arteries. Carotid plaques with IPH on MR imaging were included in the analysis. The age (fresh or recent) and the volume of IPH for each plaque were evaluated.

Results: In total, 41 carotid plaques in 37 patients (mean age 70.2 ± 11.0 years old; 32 males) were eligible for statistical analysis. The absolute volume of fresh IPH in plaques with MFCD was significantly larger than that in plaques without MFCD (109.83 ± 75.49 mm³ vs. 30.54 ± 20.62 mm³, P = 0.002). Logistic regression showed that the absolute volume of fresh IPH was significantly associated with MFCD before (odds ratio [OR], 1.735; 95% confidence interval [CI], 1.127–2.670; P = 0.012) and after adjusting for confounding factors (OR, 1.823; 95% CI, 1.076–3.090; P = 0.026). There was no significant association between recent IPH volume and MFCD (P > 0.05).

Conclusion: The volume of fresh IPH is independently associated with MFCD in carotid plaques, suggesting that integrity of fibrous cap may change with different age and size of IPH.

Association of Progression of Carotid Artery Wall Volume and Recurrent Transient Ischemic Attack or Stroke: A Magnetic Resonance Imaging Study

BACKGROUND AND PURPOSE

This study aimed to investigate the association between carotid plaque progression and subsequent recurrent events using magnetic resonance imaging.

METHODS

Sixty-three symptomatic patients with ipsilateral carotid atherosclerotic stenosis (30%-69% stenosis) determined by ultrasound underwent first and second carotid artery magnetic resonance imaging for carotid artery at baseline and ≥6 months after the first scan, respectively. All the patients had clinical follow-up after the second magnetic resonance scan for ≤5 years until the onset of recurrent transient ischemic attack or stroke. Presence/absence of carotid plaque compositional features, particularly intraplaque hemorrhage and fibrous cap rupture was identified. The annual progression of carotid wall volume between 2 magnetic resonance scans was measured. Univariate and multivariate Cox regression was used to calculate the hazard ratio and corresponding 95% confidence interval of carotid plaque features in discriminating recurrent events. Receiver-operating-characteristic-curve analysis was conducted to determine the area-under-the-curve of carotid plaque features in predicting recurrent events.

RESULTS

Sixty-three patients (mean age: 66.5±10.0 years old; 54 males) were eligible for final statistics analysis. During a mean follow-up duration of 55.1±13.6 months, 14.3% of patients (n=9) experienced ipsilateral recurrent transient ischemic attack/stroke. The annual progression of carotid wall volume was significantly associated with recurrent events before (hazard ratio, 1.14 per 10 mm³; 95% confidence interval, 1.02-1.27; P=0.019) and after (hazard ratio, 1.19 per 10 mm3; 95% confidence interval, 1.03-1.37; P=0.022) adjusted for confounding factors. In discriminating the recurrence of transient ischemia attack/stroke, receiver-operator curve analysis indicated that combined with annual progression of wall volume, there was a significant incremental improvement in the area-under-the-curve of intraplaque hemorrhage (area-under-the-curve: 0.69-0.81) and fibrous cap rupture (area-under-the-curve: 0.73-0.84).

CONCLUSIONS

The annual progression of carotid wall volume is independently associated with recurrent ischemic cerebrovascular events, and this measurement has added value for intraplaque hemorrhage and fibrous cap rupture in predicting future events.

Carotid Intraplaque Hemorrhage Imaging with Quantitative Vessel Wall T1 Mapping: Technical Development and Initial Experience

Purpose To develop a three-dimensional (3D) high-spatial-resolution time-efficient sequence for use in quantitative vessel wall T1 mapping. Materials and Methods A previously described sequence, simultaneous noncontrast angiography and intraplaque hemorrhage (SNAP) imaging, was extended by introducing 3D golden angle radial k-space sampling (GOAL-SNAP). Sliding window reconstruction was adopted to reconstruct images at different inversion delay times (different T1 contrasts) for voxelwise T1 fitting. Phantom studies were performed to test the accuracy of T1 mapping with GOAL-SNAP against a two-dimensional inversion recovery (IR) spin-echo (SE) sequence. In vivo studies were performed in six healthy volunteers (mean age, 27.8 years ± 3.0 [standard deviation]; age range, 24-32 years; five male) and five patients with atherosclerosis (mean age, 66.4 years ± 5.5; range, 60-73 years; five male) to compare T1 measurements between vessel wall sections (five per artery) with and without intraplaque hemorrhage (IPH). Statistical analyses included Pearson correlation coefficient, Bland-Altman analysis, and Wilcoxon rank-sum test with data permutation by subject. Results Phantom T1 measurements with GOAL-SNAP and IR SE sequences showed excellent correlation (R² = 0.99), with a mean bias of -25.8 msec ± 43.6 and a mean percentage error of 4.3% ± 2.5. Minimum T1 was significantly different between sections with IPH and those without it (mean, 371 msec ± 93 vs 944 msec ± 120; P = .01). Estimated T1 of normal vessel wall and muscle were 1195 msec ± 136 and 1117 msec ± 153, respectively. Conclusion High-spatial-resolution (0.8 mm isotropic) time-efficient (5 minutes) vessel wall T1 mapping is achieved by using the GOAL-SNAP sequence. This sequence may yield more quantitative reproducible biomarkers with which to characterize IPH and monitor its progression. ^© RSNA, 2017.

Identification of intraplaque haemorrhage in carotid artery by simultaneous non-contrast angiography and intraPlaque haemorrhage (SNAP) imaging: a magnetic resonance vessel wall imaging study

OBJECTIVES

To investigate the usefulness of Simultaneous Non-contrast Angiography and intraPlaque haemorrhage (SNAP) imaging in characterising carotid intraplaque haemorrhage (IPH) compared with magnetisation-prepared rapid acquisition gradient-echo (MP-RAGE) sequence.

METHODS

Fifty-four symptomatic patients (mean age: 63.1 ± 5.7 years, 38 males) with carotid atherosclerosis were recruited and underwent carotid MR imaging. The presence and area of IPH on SNAP and MP-RAGE images were determined. The agreement in identifying IPH and its area between SNAP and MP-RAGE was analysed.

RESULTS

Of 1368 slices with acceptable image quality in 54 patients, 13% and 22.6% were found to have IPH on MP-RAGE and SNAP images, respectively. There was moderate agreement between MP-RAGE and SNAP sequences in identifying IPH (κ = 0.511, p = 0.029). The area of IPH on SNAP images was significantly larger than that on MP-RAGE images (17.9 ± 18.2 mm² vs. 9.2 ± 10.5 mm², p < 0.001). For IPHs detected by SNAP imaging, the area of IPHs also detected by the MP-RAGE sequence was significantly larger than that of IPHs not detected by the MP-RAGE sequence (17.9 ± 19.2 mm² vs. 6.4 ± 6.2 mm², p < 0.001).

CONCLUSION

Compared with the MP-RAGE sequence, SNAP imaging detects more IPHs, particularly for smaller IPHs, suggesting that SNAP imaging might be a more sensitive tool for identification of carotid haemorrhagic plaques.

KEY POINTS

• Moderate agreement was found between SNAP and MP-RAGE in identification of IPH • SNAP imaging might be a more sensitive tool to detect carotid IPHs • Compared with the MP-RAGE sequence, SNAP imaging can detect carotid IPHs with smaller size • SNAP imaging can help clinicians to optimise the treatment strategy.

[Interaction between family history of diabetes and hyperlipidemia on risk of diabetes in population with normotension in Harbin: a cross-sectional study]

Objective: To explore the interaction between family history of diabetes and hyperlipidemia on the risk of diabetes in population with normotension. Methods: A multistage stratified probability random sampling was conducted to select a representative sample of urban residents aged 20-74 years in Harbin. A total of 376 diabetes patients with normotension and 3 692 residents with normal blood pressure, normal fasting glucose, and normal 2 hours glucose from OGTT were surveyed. The interaction was evaluated by using crossover analysis and additive model. Results: Multivariate logistic regression analysis indicated that there was a possible additive interaction between family history of diabetes and hyperlipidemia on the risk of diabetes. The relative excess risk due to the interaction, the attributable proportion due to the interaction, and the synergy index were 1.97 (95%CI:-0.32-4.26), 0.30 (95%CI: 0.03-0.57), and 1.54 (95%CI: 0.96-2.47), respectively. There were significant combination effects between family history of diabetes and high both total cholesterol and triglyceride, isolated high total cholesterol, and isolated high triglyceride levels; the ORs were 10.55 (95%CI: 5.62-19.80), 7.81 (95%CI: 3.65-16.71) and 5.13 (95%CI: 3.22-8.16), respectively. Conclusion: There might be synergistic effect between family history of diabetes and hyperlipidemia on the risk of diabetes in population with normotension.

[Perioperational management of gynecological cancer patients with severe internal medical complications: a serial of 37 clinical cases]

Objective: To evaluate the effectiveness and safety of perioperational management of gynecological cancer patients with severe internal medical complications. Methods: We collected 37 cases of gynecological cancer patients with severe internal medical complications who were hospitalized in Peking University First Hospital from Jan. 2010 to Nov. 2014. All of the cases were planned to move to ICU right after operation based on the preoperational assessment of anesthetist and physician. The median age was 69.4 years, and 25 cases (68%,25/37) of them were over 70 years old. The pathological types, preoperational complications, preoperational preparation, process of anesthesia and surgery, post-operational short-term morbidity were retrospectively analyzed. Results: (1) Pathological type: among 37 cases of gynecological cancer patients, 16 cases of endometrial cancer, 12 cases of ovarian cancer, 5 cases of vulvar cancer, 3 cases of uterine sarcoma and 1 case of fallopian cancer. (2) Preoperational complication: all the patients had more than 2 types of internal complications, 34 cases (92%, 34/37)of them had no less than 3 types of internal complications. The preoperational complications mainly included 25 cases of hypertension, 13 cases of coronary heart disease and 5 cases of arrhythmia, 5 cases of history of cerebral infarction or hemorrhage, 19 cases of diabetes and 1 case of obesity, 6 cases of allergic asthma and history of pulmonary embolism. (3) Preoperational preparation: medication were taken according to internal physicians to make blood pressure lower than 140/90 mmHg(1 mmHg=0.133 kPa), fasting blood glucose lower than 8.0 mmol/L, postprandial blood glucose lower than 10.0 mmol/L and cardiac function return to a generally normal status. (4) Process of anesthesia and surgery: 37 cases completed operation successfully after preoperational anesthetic assessment and internal medication. No perioperational death was observed. (5) Post-operational morbidity: 17 cases of post-operational short-term morbidity were observed before discharge, including 9 cases of poor wound healing, 5 cases of gastro-intestinal dysfunction and 3 cases of pulmonary infection. All of them were improved or cured. Conclusion: Surgery is safe and applicable to gynecological cancer patients with severe internal medical complications on the compressive management of anesthesia assessment, perioperational internal adjustment and post-operational multi-discipline treatment.

Association between proximal internal carotid artery steno-occlusive disease and diffuse wall thickening in its petrous segment: a magnetic resonance vessel wall imaging study

PURPOSE

Significant stenosis or occlusion in carotid arteries may lead to diffuse wall thickening (DWT) in the arterial wall of downstream. This study aimed to investigate the correlation between proximal internal carotid artery (ICA) steno-occlusive disease and DWT in ipsilateral petrous ICA.

METHODS

Symptomatic patients with atherosclerotic stenosis (>0%) in proximal ICA were recruited and underwent carotid MR vessel wall imaging. The 3D motion sensitized-driven equilibrium prepared rapid gradient-echo (3D-MERGE) was acquired for characterizing the wall thickness and longitudinal extent of the lesions in petrous ICA and the distance from proximal lesion to the petrous ICA. The stenosis degree in proximal ICA was measured on the time-of-flight (TOF) images.

RESULTS

In total, 166 carotid arteries from 125 patients (mean age 61.0 ± 10.5 years, 99 males) were eligible for final analysis and 64 showed DWT in petrous ICAs. The prevalence of severe DWT in petrous ICA was 1.4%, 5.3%, 5.9%, and 80.4% in ipsilateral proximal ICAs with stenosis category of 1%-49%, 50%-69%, 70%-99%, and total occlusion, respectively. Proximal ICA stenosis was significantly correlated with the wall thickness in petrous ICA (r = 0.767, P < 0.001). Logistic regression analysis showed that proximal ICA stenosis was independently associated with DWT in ipsilateral petrous ICA (odds ratio (OR) = 2.459, 95% confidence interval (CI) 1.896-3.189, P < 0.001].

CONCLUSION

Proximal ICA steno-occlusive disease is independently associated with DWT in ipsilateral petrous ICA.

Molecular cloning and expression pattern of oriental river prawn (Macrobrachium nipponense) nitric oxide synthase

Nitric oxide synthase (NOS) produces nitric oxide (NO) by catalyzing the conversion of l-arginine to l-citrulline, with the concomitant oxidation of nicotinamide adenine dinucleotide phosphate. Recently, various studies have verified the importance of NOS invertebrates and invertebrates. However, the NOS gene family in the oriental river prawn Macrobrachium nipponense is poorly understood. In this study, we cloned the full-length NOS complementary DNA from M. nipponense (MnNOS) and characterized its expression pattern in different tissues and at different developmental stages. Real-time quantitative polymerase chain reaction (RT-qPCR) showed the MnNOS gene to be expressed in all investigated tissues, with the highest levels observed in the androgenic gland (P < 0.05). Our results revealed that the MnNOS gene may play a key role in M. nipponense male sexual differentiation. Moreover, RT-qPCR revealed that MnNOS mRNA expression was significantly increased in post-larvae 10 days after metamorphosis (P < 0.05). The expression of this gene in various tissues indicates that it may perform versatile biological functions in M. nipponense.