There are various examination methods for cardiovascular diseases. Non-invasive diagnosis and prognostic information acquisition are the current research hotspots of related imaging examinations. Positron emission tomography (PET)/magnetic resonance imaging (MRI) is a new advanced fusion imaging technology that combines the molecular imaging of PET with the soft tissue contrast function of MRI to achieve their complementary advantages. This article briefly introduces several major aspects of cardiac PET/MRI in the diagnosis of cardiovascular disease, including atherosclerosis, ischemic cardiomyopathy, nodular heart disease, and myocardial amyloidosis, in order to promote cardiac PET/MRI to be more widely used in precision medicine in this field.
In this paper, the Fourier transform based minimum mean square error (FT-based MMSE) method is used to calculate the regional cerebral blood volume (rCBV) in magnetic resonance (MR) perfusion imaging, and the method is improved to handle the existing noise in the imaging process. In the experiments with signal-to-noise ratio (SNR) of 50 dB, the rCBV values were compared with the results using MMSE method. The effects of different SNRs on the estimation of rCBV were analyzed. The experimental results showed that MMSE was a simple way to filter the measurement noise, and could calculate rCBV accurately. Compared with other existing methods, the present method is not sensitive to environment, and furthermore, it is suitable to deal with the perfusion images acquired from the environment with larger SNR.
ObjectiveTo research on the effect of nursing intervention on CT scanning success rate and image quality in head CT perfusion imaging for cerebral ischemia patients. MethodBetween June 2013 and July 2014, we retrospectively analyzed the clinical data of 203 patients who underwent CT perfusion imaging for cerebral ischemia. All the patients received nursing intervention including the following aspects:body position, psychology, sedation, leakage of contrast medium, allergic reaction, etc. ResultsA total of 199 patients successfully underwent the examination, among whom there were 190 (93.6%) satisfactory and 9 (4.5%) qualified results. The other four patients (1.9%) stopped examination because of motion artifacts. So the success rate came to 98.1%, and the failure rate was 1.9%. ConclusionsWith nursing intervention before, during and after CT scanning, patients with acute cerebral ischemia can accept higher success rate in examining and satisfactory image quality. At the same time, the nursing service was also improved.
ObjectiveTo explore the application value of dual-phase dual-energy CT (DECT) perfusion imaging in preoperative lung function assessment of lung cancer patients. MethodsData were collected from patients with stageⅠA non-small cell lung cancer who underwent surgical treatment in the Department of Thoracic Surgery, the First Affiliated Hospital of Nanjing Medical University, from November 2022 to June 2024. All patients underwent DECT perfusion imaging and pulmonary function testing (PFT) before surgery. PFT observation indicators included ventilation function indicators such as forced expiratory volume in one second (FEV1), forced vital capacity (FVC), 1-second rate (FEV1/FVC), maximal voluntary ventilation (MVV), and diffusion function indicators such as diffusing capacity for carbon monoxide (DLCO) and DLCO per liter of alveolar volume (DLCO/VA). The software eXamine was used to obtain quantitative parameters of DECT perfusion imaging, including volume parameters and perfusion parameters of both lungs and each lung lobe. The correlation between the volume parameters and perfusion parameters of both lungs and the ventilation and diffusion function indicators of the patients, as well as the differences in quantitative parameters of each lung lobe, was analyzed. ResultsThe end-inspiration lung volume and biphasic volume difference were strongly positively correlated with FEV1 and FVC (r=0.636, r=0.682, r=0.614, r=0.624, P<0.001) and moderately positively correlated with MVV and DLCO (r=0.499, r=0.514, r=0.549, r=0.447, P<0.001); the end-expiration lung volume was weakly negatively correlated with DLCO/VA (r=−0.295, P=0.026); the volume ratio was positively correlated with FEV1, FVC, MVV, and MVV% (r=0.424, r=0.399, r=0.415, r=0.310, P<0.05); the end-inspiration iodine content was weakly positively correlated with DLCO/VA% (rs=0.292, P=0.030); the end-expiration iodine content was weakly positively correlated with FEV1, FVC, MVV, DLCO%, and DLCO/VA (r=0.307, r=0.299, r=0.295, r=0.366, r=0.320, P<0.05) and moderately positively correlated with DLCO (r=0.439, P<0.001); the end-inspiration iodine concentration was negatively correlated with FEV1, FVC, MVV, and MVV% (rs=−0.407, rs=−0.426, rs=−0.352, rs=−0.277, P＜0.05); the end-expiratory phase iodine concentration is moderately positively correlated with DLCO/VA (r=0.403, P=0.002); both the iodine concentration difference and the iodine concentration ratio are moderately positively correlated with FEV1, FEV1%, FVC, MVV, MVV% (P<0.05). The lung volume and iodine concentration ratio values are both highest in the left upper lung lobe and lowest in the right middle lung lobe; the differences in lung volume, lung volume ratio, intrapulmonary iodine content, and intrapulmonary iodine concentration difference, from high to low, are in the lower lobes of both lungs, the upper lobes of both lungs, and the right middle lung lobe. ConclusionDual-phase DECT perfusion imaging can accurately assess overall lung function and quantify regional lung function.
ObjectiveTo explore the clinical value of dual-source CT perfusion imaging (CTPI) in the assessment of cerebral hemodynamic changes in patients with internal carotid atherosclerosis. MethodsThirty patients diagnosed to have internal carotid atherosclerosis by CT angiography examination with various degrees of stenosis or occlusion were treated between January 2012 and May 2013. Whole brain perfusion imaging was performed on all the patients. We rebuilt the CTPI figure parameters respectively, including cerebral blood volume (CBV), blood flow (CBF), mean transit time (MTT) and time to peak (TTP) to assess brain tissue perfusion. ResultsIn the 30 patients with internal carotid atherosclerosis, 8 had mild stenosis lumen, 12 moderate stenosis, 7 severe stenosis and 3 had occlusion. In mild stenosis cases, TTP of stenosis-side vessels was higher than those of coutralateral side (P<0.05), and there were no significant differences in other perfusion parameters between bilateral vessels among mild stenosis cases (P>0.05). MTT and TTP of stenosis-side vessels were higher than those of contralateral side in moderate stenosis cases (P<0.05). In severe stenosis or obstruction cases, MTT and TTP of stenosis-side vessels were higher than those of contralateral side, while CBF and CBV of stenosis-side vessels were lower than contralateral side (P<0.05). Twenty-two in the 30 cases had perfusion abnormalities, and there was a significant difference between the stenosis side cerebral perfusion and the healthy side mirror area (P<0.05). ConclusionCTPI can reflect brain tissue perfusion early and comprehensively, and fully reflect internal carotid atherosclerosis caused by severe stenosis or occlusion of cerebral hemodynamic changes, which provides important information for clinical treatment and helps clinicians to formulate individualized treatment plan.
ObjectiveTo estimate the radiation dose (RD) to the general public and nuclear medicine technicians from patients undergoing 99mTc-methoxy isobutyl isonitrile (MIBI) myocardial perfusion imaging. MethodsFrom January to June 2015, 55 patients including 30 males and 25 females aged between 25 and 87 years[averaging (63.6±15.1)years] ready to undergo myocardial perfusion scintigraphy with 99mTc-MIBI were prospectively recruited in this study. Approximately at hour 1.5 after injection of 99mTc-MIBI, whole-body dose-equivalent rate was measured with a radiation-survey meter at 0.3 meter and 1.0 meter from the patients. On the basis of human 99mTc-MIBI metabolic rate proposed by the International Commission of Radiological Protection and human social contact model proposed by the National Council on Radiation Protection and Measurements, the RDs to the general public from patients who had completed 99mTc-MIBI myocardial perfusion imaging and left nuclear medicine department were calculated. On the assumption that a nuclear medicine technician typically spent 5 minutes at a distance of 0.3 meter for positioning the patient, the technician's RD was also estimated. ResultsThe RD to a family member sleeping with the patient at night was predicted to be 42.88-160.55 μSv, to a family member contacting the patient at daytime 7.50-29.38 μSv, to a colleague 9.89-38.78 μSv and to a nearby passenger 124.48-466.06 μSv. The RD to a technician per 99mTc-MIBI myocardial perfusion imaging procedure was predicted to be 1.72-6.44 μSv. ConclusionThe predicted RDs to the general public and technicians from exposure of patients undergoing 99mTc-MIBI myocardial perfusion imaging are significantly lower than the regulatory dose limits.
ObjectiveTo investigate the clinical value of multi-slice spiral CT perfusion imaging for blood supply of pulmonary mixed ground-glass nodules (mGGN). MethodsThe mGGN patients were retrospectively analyzed from March 2011 to May 2015 in Affiliated Hospital of Hebei University of Engineering, Handan First Hospital and Xingtai People's Hospital. Multi-slice spiral CT perfusion imaging for blood supply was applied to evaluate the blood supply of solid lesions in mGGN, and the diagnostic values of CT perfusion parameters were compared for differentiating the benigh mGGN from the malignant mGGN. ResultsTotally 97 mGGN patients were enrolled in this study, in which 80 were malignant mGGN and 17 were benigh mGGN. Blood volume (BV), peak enhancement image (PEI) and permeability surface (PS) in malignant mGGN lesions were higher than those of benign lesions, while the time to peak was less than that of benign lesions, and the differences were all statistically significant (P < 0.05). BV, PEI and PS in minimally invasive adenocarcinoma (MIA) and invasive adenocarcinoma (IAC) patients were significantly higher than those in the patients with precancerous lesions (P < 0.05). BV and PS in IAC patients were significantly higher than those in MIA patients (P < 0.05). Logistic regression analysis showed that IAC, MIA and the precancerous lesions, BV, PEI and PS were positively correlated with mGGN. Receiver operating characteristic (ROC) curve showed that the sensitivity, specificity, positive predictive value, negative predictive value, and diagnostic accuracy rates with BV+PS+PEI combined, were 95.28%, 86.65%, 91.10%, 87.52% and 91.76%, respectively, while the area under ROC curve was significantly higher than those with single parameter (P < 0.05). ConclusionMulti-slice spiral CT perfusion imaging can evaluate the blood supply of mGGN, and BV+PS+PEI combined can be used in differentiation of the benigh and malignant mGGN.
Objective To review the principles and techniques of CT perfusion imaging and its applications in the imaging diagnosis of abdominal disorders. Methods All the relevant literatures were reviewed. The principles and techniques of CT perfusion imaging were described and summarized in detail. The functional information of a target abdominal organ (e.g. the liver and pancreas) revealed by CT perfusion imaging, such as hemodynamics and microcirculation status, was also evaluated. Results In addition to the morphologic information, CT perfusion imaging can also provide functional information about the circulation parameters of target abdominal organs. Moreover, such functional information can be generated for the neovasculature and microcirculation of tumor lesions of abdominal organs, which is very helpful for not only the diagnosis, but also the evaluation of tumor invasiveness and response to treatment. Conclusion CT perfusion imaging offers an effective method for studying abdominal disorders by providing functional information that is quite useful for the differential diagnosis and assessment of therapeutic response.
ObjectiveTo evaluate the dynamic changes of blood flow and blood pressure of acute hindlimb ischemia of rats by laser Doppler flowmetry (LDF) and laser Doppler perfusion imaging (LDPI). MethodsThe acute hindlimb ischemia model of rats was established by resection of rats femoral arteries of left hindlimb. The blood flow and blood pressure between operated and nonoperated hindlimbs were examined by LDF on 2, 7, 14, 28, and 49 d after operation. And the blood flow was evaluated by LDPI on 7 d after operation. ResultsAll rats survived after operation and no hindlimb necrosis occurred. The mean score was 2 on 14 d after operation and 1 on 49 d after operation. The ratio of blood flow between operated and nonoperated hindlimbs on 2 d after operation significantly increased from 1 to 1.31±0.439 (P=0.021). The ratio of blood flow on 7 d (0.82±0.538) and 14 d (0.93±0.294) after operation was significantly lower than that on 2 d after operation (P=0.032 and P=0.019), although the difference between the two former was not significant (P=0.502). Furthermore, the ratio of blood flow on 28 d after operation reached the bottom (0.41±1.970), which was obviously lower than that on 2, 7, and 14 d after operation (P=0.004, P=0.007, and P=0.006). The blood flow of operated hindlimbs recovered approximately the value before operation (0.98±0.093), which was significantly lower than that on 2 d (P=0.010), higher than that on 28 d (P=0.005), but not different from that on 7 d and 14 d after operation (P=0.126 and P=0.382). The ratio of blood pressure between operated and nonoperated hindlimbs on 2 d after operation significantly increased from 1 to 0.47±0.375 (P=0.031). The ratio of blood pressure decreased on 7 d after operation (0.44±0.118), which was not different from that on 2 d after operation (P=0.203). Furthermore, the ratio of blood pressure on 14 d after operation reached the bottom (0.35±0.115), which was obviously lower than that on 2 d and 7 d after operation (P=0.001 and P=0.036). On 28 d after operation, the ratio of blood pressure increased (0.54±0.146), which was significantly higher than that on 14 d after operation (P=0.008), while not different from that on 2 d (P=0.493) and 7 d after operation (P=0.551). The ratio of blood pressure recovered approximately the value before operation (0.97±0.094), which was significantly higher than that on 2, 7, 14, and 28 d (P=0.013, P=0.021, P=0.002, and P=0.031). ConclusionAcute hindlimb ischemia model of rats can be established by resection of rats femoral arteries of left hindlimb and the most serious stage of hindlimb ischemia is on 14-28 d after operation. LDF and LDPI are of importance for monitoring the dynamic changes of rats hindlimb ischemia after operation.
ObjectiveTo investigate the diagnostic performance of parameters of arterial enhancement fraction (AEF) based on enhanced CT with histogram analysis in the severity of liver cirrhosis.MethodsThe patients with liver cirrhosis clinically confirmed and met the inclusion criteria were included from January 2016 to December 2018 in the First Affiliated Hospital of Chengdu Medical College, then them were divided into grade A, B, and C according to the Child-Pugh score. Meanwhile, the patients without liver disease were selected as the control group. All patients underwent the upper abdomen enhanced CT scan with three-phase and the biochemical examination of liver function. The parameters of AEF histogram were obtained by using the CT Kinetics software, and the aspartic aminotransferase and platelet ratio index (APRI) was calculated. The differences of parameters of AEF histogram and APRI among these patients with liver cirrhosis and without liver disease were analyzed. The diagnostic performance was evaluated by using the area under curve (AUC) of receivers operating characteristic curve.ResultsEighty-five patients with liver cirrhosis were included in this study, including 25, 41, and 19 patients with grade A, B, and C of Child-Pugh score, respectively, and there were 20 patients in the control group. The consistencies in measuring the parameters of AEF histogram twice for the same observer and between the two observers were good (intraclass correlation coefficient was 0.938 and 0.907, respectively). The mean, median, and kurtosis of AEF histogram and the APRI among the grade A, B, C of Child-Pugh score, and control group had significant differences (all P<0.001) and these indexes were positively correlated with the severity of liver cirrhosis (rs=0.811, P<0.001; rs=0.827, P<0.001; rs=0.731, P<0.001; rs=0.711, P<0.001). The AUC of the mean, median, kurtosis, and APRI in diagnosing grade A of liver cirrhosis was 0.829, 0.841, 0.747, and 0.718, respectively; which in diagnosing grade B of liver cirrhosis was 0.847, 0.734, 0.704, and 0.736, respectively; in diagnosing grade C of liver cirrhosis was 0.646, 0.825, 0.782, and 0.853, respectively.ConclusionThe mean and median of AEF histogram parameters based on enhanced CT with three-phase and serological APRI are useful in diagnosis of grage A, B, and C of liver cirrhosis, respectively.