Octreotide-induced acute life-threatening gallstones after vicarious contrast medium excretion:A case report

BACKGROUND Octreotide is widely used for the treatment of acromegaly,neuroendocrine tumors,and secretory diarrhea.However,long-term octreotide treatment can increase the incidence of gallstones.Vicarious contrast medium excretion(VCME)through the hepatobiliary system is well known.However,few studies have reported octreotide-induced acute gallstones following VCME.CASE SUMMARY A 69-year-old man presented with left lower back pain and hematuria caused by a fall.The patient had a history of polycystic kidney disease.VCME occurred following renal artery embolization for a ruptured polycystic kidney.After 5 d of treatment with octreotide,the patient developed acute gallstones and intrahepatic cholestasis which further induced pancreatitis and cholangitis.He was discharged after hemodialysis,antibiotics,and supportive treatments.CONCLUSION For patients with a high-risk of VCME,octreotide should be cautiously administered and carefully monitored.

Preliminary clinical application of an adaptive iterative statistical reconstruction algorithm inhead and neck computed tomography angiography with low tube voltage and a low concentration of contrast medium

Objective To evaluate the feasibility of using a low concentration of contrast medium （Visipaque 270 mgl/mL）, low tube voltage, and an advanced image reconstruction algorithm in head and neck computed tomography angiography （CTA）. Methods Forty patients （22 men and 18 women; average age 48.7 ± 14.25 years; average body mass index 23.9 ± 3.7 kg/m^2） undergoing CTA for suspected vascular diseases were randomly assigned into two groups. Group A （n = 20） was administered 370 mgl/mL contrast medium, and group B （n = 20） was administered 270 mgl/mL contrast medium. Both groups were administered at a rate of 4.8 mL/s and an injection volume of 0.8 mL/kg. Images of group A were obtained with 120 kVp and filtered back projection （FBP） reconstruction, whereas images of group B were obtained with 80 kVp and 80% adaptive iterative statistical reconstruction algorithm （ASiR）. The CT values and standard deviations of intracranial arteries and image noise on the corona radiata were measured to calculate the contrast-to-noise ratio （CNR） and signal-to-noise ratio （SNR）. The beam-hardening artifacts （BHAs） around the skull base were calculated. Two readers evaluated the image quality with volume rendered images using scores from 1 to 5. The values between the two groups were statistically compared. Results The mean CT value of the intracranial arteries in group B was significantly higher than that in group A （P 〈 0.001）. The CNR and SNR values in group B were also statistically higher than those in group A （P 〈 0.001）. Image noise and BHAs were not significantly different between the two groups. The image quality score of VR images of in group B was significantly higher than that in group A （P = 0.001）. However, the quality scores of axial enhancement images in group B became significantly smaller than those in group A （P〈 0.001）. The CT dose index volume and dose-length product were decreased by 63.8% and 64%, respectively, in group B （P 〈 0.001 for both）. Conclusion Visipaque combined with 80 kVp and 80% ASiR provided similar image quality in intracranial CTA with 64% radiation dose reduction compared with the use of lopamidol, 120 kVp, and FBP reconstruc-tion.

Low contrast medium and radiation dose for hepatic computed tomography perfusion of rabbit VX2 tumor

AIM:To evaluate the feasibility of low contrast medium and radiation dose for hepatic computed tomography(CT) perfusion of rabbit VX2 tumor.METHODS:Eleven rabbits with hepatic VX2 tumor underwent perfusion CT scanning with a 24-h interval between a conventional tube potential(120 k Vp) protocol with 350 mg I/m L contrast medium and filtered back projection,and a low tube potential(80 k Vp) protocol with 270 mg I/m L contrast medium with iterative reconstruction.Correlation and agreement among perfusion parameters acquired by the conventional and low dose protocols were assessed for the viable tumor component as well as whole tumor.Image noise and tumor-to-liver contrast to noise ratio during arterial and portal venous phases were evaluated.RESULTS:A 38% reduction in contrast medium dose(360.1 ± 13.3 mg I/kg vs 583.5 ± 21.5 mg I/kg,P < 0.001) and a 73% decrease in radiation dose(1898.5 m Gy·cm vs 6951.8 m Gy·cm) were observed.Interestingly,there was a strong positive correlation in hepatic arterial perfusion(r = 0.907,P < 0.001;r = 0.879,P < 0.001),hepatic portal perfusion(r = 0.819,P = 0.002;r = 0.831,P = 0.002),and hepatic blood flow(r = 0.945,P < 0.001;r = 0.930,P < 0.001) as well as a moderate correlation in hepatic perfusion index(r = 0.736,P = 0.01;r = 0.636,P = 0.035) between the low dose protocol with iterative reconstruction and the conventional protocol for the viable tumor component and the whole tumor.These two imaging protocols provided a moderate but acceptable agreement for perfusion parameters and similar tumorto-liver CNR during arterial and portal venous phases(5.63 ± 2.38 vs 6.16 ± 2.60,P = 0.814;4.60 ± 1.27 vs 5.11 ± 1.74,P = 0.587).CONCLUSION:Compared with the conventional protocol,low contrast medium and radiation dose with iterative reconstruction has no significant influence on hepatic perfusion parameters for rabbits VX2 tumor.

Introduction of Manganese Oxide into Carbon Nanotubes for the Potential Applications as a Contrast Medium

Manganese compound with evident toxicity is widely employed as the contrast medium for clinicalexaminations such as magnetic resonance imaging(MRI).In the present work,a feasible way with the applica-tion of vacuum impregnation and rotary evaporation was proposed to introduce manganese chloride hydrate intothe inner cavities of template - synthesized carbon nanotubes(CNTs),and then a process of alkali treatmentwas used to liberate the loaded CNTs from the template.It is notable that the alkali attack in the presence ofresidual oxygen also resulted in a series of changes in chemical compositions of guest substances,and the ulti-mate compound of manganese was found to be manganese oxide(Mn3O4) by X-ray diffraction and transmissionelectron microscopy.Determinations of energy dispersive spectrum under scanning electron microscopy showeda high-content filling(more than 50 wt%) of Mn3O4 in the loaded CNTs.This work developed a feasible andconvenient way for the encapsulation of guest substances to reduce bio-toxic effects.

Prevention Strategies of Contrast Medium Induced Nephropathy (CIN): A Review of the Current Literature

Contrast medium induced nephropathy is the third most common cause of renal failure for inpatients and represents the 10% of all acute kidney injury occurring during hospital-stay. It is associated with prolonged hospitalization, cost increase and, above all, an unfavourable short- and long-term prognosis. Here, the authors discuss about the contrast medium induced nephropathy prevention strategies, from the identification of patients at risk and drugs potentially nephrotoxic, to the hydration with possible administration of drugs that appeared to be, in some contexts, nephron-protective, and finally we analyze the radiological procedure aimed at the correct choice of type and administration modality of the contrast medium according to current literature.

Hemodynamic and morphologic changes of peripheral hepatic vasculature in cirrhotic liver disease: A preliminary study using contrast-enhanced coded phase inversion harmonic ultrasonography

AIM: To provide the useful information for the diagnosis of liver cirrhosis by observing the morphology of peripheral hepatic vessels and the hemodynamics of microbubble arrival time in these vessels.METHODS: Twenty-one subjects including 5 normal volunteers and 16 patients (liver cirrhosis, n=10;chronic hepatitis, n=6) were studied by contrast-enhanced coded phase inversion harmonic sonography (GE LOGIQ9 series) using a 6-8 MHz convex-arrayed wide-band transducer. The images of peripheral hepatic artery,portal and hepatic vein were observed in real-time for about 2 min after intravenous injection of Levovist. The time when microbubbles appeared in the peripheral vessels (microbubble arrival time) was also recorded. The morphologic changes of peripheral hepatic vasculature were classified as marked, slight, and no changes based on the regularity in caliber, course, ramification, and the delineation of vessels compared to normal subjects.RESULTS: The microbubble arrival time at peripheral artery, portal, and hepatic vein was shorter in cirrhotic patients than in chronic hepatitis patients and normal subjects. The marked, slight and no morphologic changes of peripheral hepatic vasculature found in 5 (5/6,83.3%), 1 (1/6, 16.7% ), and 0 (0/6, 0%) liver cirrhosis patients, respectively, and in 1 (1/10, 10%), 6 (6/10,60%), and 3 (3/10, 30%) chronic hepatitis patients,respectively. There was a significant difference between the two groups (P＜0.001).CONCLUSION: Evaluation of the hemodynamics and morphology of peripheral hepatic vasculature by contrast-enhanced coded pulse inversion harmonic sonography can provide useful information for the diagnosis of liver cirrhosis.

Differentiation between malignant and benign nodules in the liver: Use of contrast C^3-MODE technology

AIM: To investigate the value of contrast-enhanced C3-MODE technology in differentiating malignant nodules of liver from the benign ones. METHODS: Forty-six nodules in 36 patients (29 men and 7 women) were studied by contrast-enhanced C3-MODE technology and contrast-enhanced CT in 1 wk before the biopsy or operation. A low MI monitor and a high MI flash imaging were intermittently performed. After the injection of contrast agent, the period from 10 to 30 s and the time later than 100 s were respectively defined as early arterial phase and the late phase. The vascularities of the liver nodules in the two phases were combined for differential diagnosis. Corresponding to the pathological diagnosis, the accuracy, sensitivity and specificity of contrast-enhanced C3-MODE technology were compared to those of contrast-enhanced CT. RESULTS: By C3-MODE technology, 33 of the 46 liver nodules were demonstrated as defected area in the late phase and were diagnosed as malignant tumors. Of them, 28 with hypervascularity in the early arterial phase were assessed as hepatocellular carcinoma, the other five nodules with rim-like enhancement in the early arterial phase were diagnosed as metastatic tumors. Thirteen nodules were shown as iso or hypervascularity in the late phase as well as centripetal filling in the early arterial phase and we made a diagnosis of hemangioma. Corresponding to the pathological results, the sensitivity, specificity and accuracy of contrast-enhanced C3-MODE technology in differentiating malignant and benign nodules in the liver were 97.0%, 92.3% and 95.7%, respectively. With comparison to those of contrast CT (sensitivity, 94.1%; specificity, 91.7%; accuracy, 93.5%), the difference was not significant. CONCLUSION: Contrast-enhanced C3-MODE technology can effectively differentiate malignant liver tumors from the benign nodules. It highly agrees diagnostically with the pathology. We suggest that it provides a new approach for differential diagnosis of liver nodules in addition to contrast-enhanced CT.

Biliary cystadenocarcinoma diagnosed with real-time contrast-enhanced ultrasonography:Report of a case with diagnostic features

Biliary cystadenocarcinoma is a very rare malignant cystic tumor of the liver,which is often misdiagnosed due to a poor recognition of it.We report a case of a 60-year-old man with biliary cystadenocarcinoma with his real time contrast enhanced ultrasound(CEUS)characteristics compared to those of computed tomography(CT)and magnetic resonance imaging(MRI),which were correlated with the surgical and pathologic findings.Cystic wall enhancement,internal septations and intra-cystic solid portions in the arterial phase were observed on CEUS after contrast agent injection.The enhancement was washed out progressively and depicted as hypo-enhancement in the portal and late phases.CT revealed a large irregular cystic lesion in the left liver lobe with no clear septations and solid components.MRI showed an irregular cystic occupying lesion with septations.

Use of carbon dioxide as negative contrast agent for magnetic resonance cholangiopancreatography

AIM: To evaluate the effects of using CO2 as negative contrast agent in decreasing the overlapping on the pancreaticobiliary system from intestinal fluids.METHODS:We evaluated the magnetic resonance cholangiopancreatography(MRCP) images in 117 patients divided into two groups(group 1,without taking gas producing crystals to produce CO2,n=64;group 2,with CO2,n=53)in a 1.5T unit using MRCP sequence.Anatomic locations of intestinal fluids distribution,overlapping with common bile duct(CBD)and pancreatic duct(PD),were evaluated.RESULTS:In the group with CO2,the decrease in distribution of intestinal fluids was significant in the gastric antrum(P=0.001)and duodenal bulb(P<0.001),but not in the gastric fundus and body and in the second portion of the duodenum(P=1.000,P=0.171,and P=0.584 respectively).In the group with CO2,the decrease in overlapping with CBD was significant(P< 0.001),but the decrease in overlapping with PD was not (P=0.106).CONCLUSION:MRCP with carbon dioxide as negative contrast agent would decrease intestinal fluids in the gastric antrum and duodenal bulb,thereby decreasing overlapping with the CBD.

Pulmonary Sequestration: Three Dimensional Dynamic Contrast-enhanced MR Angiography and MRI

In order to evaluate the diagnostic value of three dimentional contrast enhanced MR angiography and MRI for pulmonary sequestration, 5 patients with pulmonary sequestration underwent 3D fast imaging by steady state precession (FISP) with a contrast medium and breath holding following chest radiography, CT and MR scans. The reconstructed MR angiography was performed using maximum intensity projection (MIP) and multiplanar reconstruction (MPR) techniques. It was found that the chest radiography showed pulmonary sequestration as a persistent area of opacity in the posterior basal segment of the left lower lobe, which was close to mediastinum in 2 cases and close to diaphragma in 3 cases. CT revealed a soft issue mass beyond descending aorta and lobar emphysema around the pulmonary sequestration. And the supplying vessel was documented in 2 cases on enhanced CT. MRI demonstrated a hyperintensity mass with respect to normal lung parenchyma on T1WI and T2WI, and the origin of the supplying vessel in 3 cases. The reconstructed CE MRA using MIP or MRP techniques clearly showed the supplying vessel and its course, branches as well as draining vessels. It was concluded that 3D CE MRA of demonstrating the supplying and draining vessels to pulmonary sequestration, together with plain MRI, can provide a diagnosis and aid in surgical planning without the need for DSA.

Molecular interactions between anticancer drugs and iodinated contrast media: An in vitro spectroscopic study

Purpose: The purpose of this study is to assess molecular interactions between several anticancer drugs and an iodinated contrast medium by Fourier transform infrared spectroscopy (FT-IR) and ultraviolet-visible spectroscopy (UV-Vis). Materials and Methods: Iopamidol (IPM) was used as an iodinated contrast medium, and mitomycin C (MTI), epirubicin hydrochloride (EPI), cisplatin (CDDP), 5-fluorouracil (5FU), irinotecan hydrochloride (CPT11), gemcitabine hydrochloride (dFdC), carboplatin (CBDCA), oxaliplatin (1OHP), paclitaxel hydrochloride (TAX) and docetaxel trihydrate (TXT) were used as anticancer drugs. For FT-IR, the purified IPM was mixed stoichiometrically with each anticancer drug as well as with a combination of MTI and EPI. After measuring each separated sample and the mixtures, the spectra of the mixtures were compared with the spectra of the sum of pure samples or the combination. For UV-Vis, IPM and anticancer drugs were dissolved in pure water;subsequently for the titration experiments, the mixtures were prepared by varying the molar ratio. IR absorption corresponds to stretching vibrations between atoms having covalent bonding, whereas UV-Vis spectra depend on molecular dynamics and shapes. Both UV-Vis and IR spectra change when there are molecular interactions such as aromatic ring stacking and hydrogen bonding. Result: IPM exhibited molecular interactions with MTI, EPI, CDDP, dFdC, CBDCA, 1OHP, TAX and TXT, as well as with the combination of MTI and EPI on FT-IR. However, molecular interactions were not observed on UV-Vis. Conclusion: Several anticancer drugs have molecular interactions with IPM, which could be clinically utilized for superselective intraarterial infusion chemotherapy.

Role of contrast-enhanced serial/spot abdominal X-rays in perioperative follow-up of patients undergoing abdominal surgery:An observational clinical study

BACKGROUND Many imaging methods such as ultrasonography,computed tomography(CT),magnetic resonance imaging,and endoscopy are used to identify the problems or complications that occur in the perioperative period and to determine the appropriate therapeutic approach.Specialists at surgical clinics and intensive care units sometimes need diagnostic procedures that can give quick results or reveal unexpected results.In particular,rapid on-site evaluation of patients followed under intensive care conditions has several advantages.AIM To determine the problems developing in patients in the perioperative period by contrast-enhanced abdominal X-ray(CE-AXR),revealing their current status or defining the effectiveness of CE-AXR.METHODS The files of the patients who underwent hepatopancreatobiliary or upper gastrointestinal surgery,whose CE-AXR film was taken,were reviewed retrospectively.Abdominal X-ray radiographs taken after ingestion of a watersoluble contrast agent(iohexol,300 mg,50 cc vial)and its application in a drain,nasogastric tube,or stent were evaluated.The contribution of the data obtained in patients who underwent CE-AXR to the diagnosis,follow-up,and treatment processes and the effectiveness of the application were investigated.RESULTS CE-AXR was applied to 131 patients in our clinic,most of whom underwent hepatopancreatobiliary or upper gastrointestinal surgery.It was determined that the data obtained from CE-AXR films taken in 98(74.8%)of the patients contributed to the diagnosis,treatment,and follow-up expectations and positively affected the clinical processes.CONCLUSION CE-AXR is a simple procedure that can be applied anywhere,especially in intensive care patients and at bedside,with a portable X-ray device.The simplicity of the procedure,less radiation exposure for the patients,less time wastage,reduction in the CT and endoscopy procedure burden and costs,quick results,rapid assessment of the situation,and enabling the monitoring of processes with repetitive procedures are important advantages.X-rays taken will be useful in terms of being a reference value during the follow-up period of the patient and determining the situation in medicolegal processes.

CT增强检查中碘对比剂外渗病人皮肤损伤风险预测模型的构建

目的:探讨CT增强检查中碘对比剂外渗病人皮肤损伤发生风险的影响因素,构建并验证风险预测模型。方法:采用便利抽样法抽取2023年1月—7月在广西医科大学第一附属医院放射科接受CT增强检查的碘对比剂外渗病人286例作为研究对象,自制CT增强检查碘对比剂外渗病人皮肤损伤风险调查问卷对病人进行调查,采用单因素分析、Logistic回归分析筛选CT增强检查中碘对比剂外渗病人皮肤损伤发生风险的影响因素,构建风险预测模型,绘制列线图,运用受试者工作特征(ROC)曲线、校准曲线评价模型。结果:CT增强检查中碘对比剂外渗病人皮肤损伤发生率为18.5%。Logistic回归分析结果显示,过敏史、碘对比剂黏稠度、碘对比剂注射速度是CT增强检查中碘对比剂外渗病人皮肤损伤的影响因素(P<0.05),基于上述结果构建的预测模型建模组ROC曲线下面积为0.842[95%CI(0.770,0.915)],约登指数为0.667,最优截断值灵敏度为0.893,特异度为0.774;验证组ROC曲线下面积为0.924[95%CI(0.872,0.975)],约登指数为0.793,最优截断值灵敏度为0.891,特异度为0.902。Hosmer-Lemeshow检验结果显示,χ2=9.566,P=0.221 5,校准曲线与参考线相接近。结论:CT增强检查中碘对比剂外渗病人皮肤损伤风险预测模型预测效能良好,可为医务人员制订个性化的预防措施提供参考。

右美托咪定预防造影剂诱导急性肾损伤机制的研究进展

造影剂诱导急性肾损伤(CI-AKI)是在血管内应用造影剂(CM)进行诊断或治疗性血管造影干预后观察到的医源性急性肾损伤(AKI)。造影剂通过肾小管毒性、肾内血管收缩和活性氧(ROS)的过量产生等方面导致肾功能受损。右美托咪定(DEX)是一种选择性α2肾上腺素能受体激动药,具有良好的抗氧化、抗炎作用,在围手术期的器官保护作用日益突显。DEX对患者术后肾功能具有保护作用。本文旨在对DEX对CI-AKI的预防作用、可能机制以及临床应用的研究进展作一综述。

碘对比剂全程化药学服务共识

目的探讨碘对比剂全程化药学服务模式,促进碘对比剂的临床合理使用。方法中国医药教育协会临床合理用药专业委员会和广东省药学会用药评价与临床科研专家委员会组织国内专家,成立《碘对比剂全程化药学服务共识》工作组,针对碘对比剂的发展历程、适应证、禁忌证、不良反应、药物相互作用、特殊人群用药、药学服务等进行文献检索、循证分析和研讨,梳理全程化药学服务的内容与流程,最终形成共识。结果制定的碘对比剂全程化药学服务共识包括检查前对患者、肾功能、合并用药和水化方案的评估,检查中有无发生对比剂外渗或发生(可疑)急性不良反应,检查后的观察时间点和随访等内容,以药学服务流程图展示各阶段的具体工作,并形成用药监护记录表用以记录工作情况。结论本共识构建了碘对比剂全程化药学服务体系,为临床医生、护理人员合理使用该类特殊药品提供了科学依据,也为药师进行相关药学服务提供了参考。

对比剂个性化在肝脏增强CT扫描的初步研究

目的探讨对比剂个性化在肝脏增强CT应用的图像质量及可重复性。方法肝脏三期增强受检者以个性化方案扫描,评价图像质量及肝实质期强化效应可重复性。结果192例受检者实际单位体重碘剂量(374.8±52.1)mgl/Kg,实际注射碘流率(1138.0±130.9)mgl/s,有效碘总量(21320.0±3017.7)mgl,肝脏EU肝实质期为(53.2±7.0)Hu。主动脉强化、动脉期时机、肝实质期强化满足诊断分别约89.06%、94.3%、97.9%;医师间主动脉强化(χ^(2)=3.333)与扫描时机(χ^(2)=1.833)、肝实质期强化效应(χ^(2)=7.667)评价未见显著差异(均P≥0.05),医师评价高度一致(kappa值分别为0.861,0.803,0.914,均P=0.000),样本均数与50Hu比较未见统计差异(t=1.745,P=0.083),变异系数为13.13%,其中16例受检者两次扫描肝实质EU分别为(49.8±6.4)Hu、(50.3±6.7)Hu,差值均数(-0.5000±2.8432)Hu与0比较未见统计差异(t=-0.703,P=0.493)。结论对比剂个性化扫描的肝脏图像质量优良、可重复性较好,易于推广应用。

纳米颗粒在动脉粥样硬化易损斑块靶向诊断成像中应用研究进展

动脉粥样硬化是一种常见的血管疾病,其特征是脂质的沉积及发生相关的炎性反应。动脉粥样硬化易损斑块是急性心血管事件的主要病理原因。因此,易损斑块的早期发现和及时干预治疗具有重要的临床意义。尽管临床上已开发出多种针对易损斑块的诊疗方法,但其导致的急性临床事件仍居高不下,而纳米颗粒在这方面表现出了巨大的潜力。纳米颗粒在影像学中应用广泛,因其独特的光学特性,可以高效标记组织和细胞以检测疾病状态;金属纳米颗粒能实现高分辨率成像;还可用作药物递送载体,提高治疗效果。文章回顾了纳米颗粒用于动脉粥样硬化易损斑块靶向诊断的研究进展,探讨纳米颗粒在相关领域的未来发展以及向临床转化的挑战与机遇。

Cerebral pseudoinfarction due to venoarterial extracorporeal membrane oxygenation:A case report

BACKGROUND Neurological complications are common in the management of venoarterial extracorporeal membrane oxygenation(VA-ECMO),with most patients requiring sedation and intubation,limiting the assessment of neurological function.Therefore,we must rely on advanced neuroimaging techniques,such as computed tomography angiography(CTA)and computed tomography perfusion(CTP).Because ECMO changes the normal blood flow pattern,it may interfere with the contrast medium in some special cases,leading to artifacts and ultimately misleading clinical decisions.CASE SUMMARY A 61-year-old man presented to a local hospital with chest tightness and pain 1 d prior to presentation.The patient was treated with VA-ECMO after sudden cardiac and respiratory arrest at a local hospital.For further treatment,the patient was transferred to our hospital.The initial consciousness assessment was not clear,and routine CTP was performed to understand the intracranial changes,which suggested a large area of cerebral infarction on the right side;however,the cerebral oxygen was not consistent with the CTP results,and the reexamination of CTA still suggested a right cerebral infarction.To identify this difference,bedside transcranial Doppler was performed,and the blood flow on both sides was different.By reducing the ECMO flow,CTP reexamination showed that the results were normal and consistent with the clinical results.On day 3,the patient was alert and showed good limb movements.CONCLUSION In patients with peripheral VA-ECMO,cerebral perfusion confirmed by CTP and CTA may lead to false cerebral infarction.

食用菌培养基废料取代商品有机肥茶园对比试验

茶园长期偏施化肥容易引起土壤板结,导致茶叶产量品质双双下降,将袋料黑木耳培养基废料作基肥有机肥施入茶园后,效果良好。为对茶园推行新的施肥方式提供理论依据,试验比较了木耳培养基废料取代商品有机肥对茶园产量、肥力及茶叶品质的影响。结果显示:茶园采用“食用菌基废料+复合肥+尿素”的施肥方式效果较好,其产量和品质略高于“商品有机肥+复合肥+尿素”施肥方式,显著优于无机化肥施肥方式(常规施肥方式);通过适当的食用菌基废料腐熟还田,可显著提高土壤的有机质含量,有效提升茶园土壤的微环境。

老年病人开展双低剂量CT冠状动脉造影的可行性研究

目的分析在老年病人中开展低管电压、低对比剂(双低剂量)CT冠状动脉造影(coronary computed tomography angiography,CCTA)的可行性。方法连续纳入2021年3月1日至8月31日在江苏省省级机关医院行CCTA检查的老年病人,随机分为2组,常规剂量组行常规剂量扫描,管电压为100 kVp,对比剂剂量为70 mL;双低剂量组行低管电压、低对比剂双低剂量扫描,管电压为70 kVp,对比剂剂量为30 mL。根据心率是否>70次/min,BMI是否>25将2组分别分为4个亚组,并比较分析2组中相对应亚组之间CCTA图像质量和辐射剂量的差异。结果在所有相对应亚组间比较,双低剂量组的辐射剂量均显著低于常规剂量组,差异具有统计学意义(P<0.01)。双低剂量组中,无论心率是否>70次/min,BMI≤25的亚组与常规剂量组对应的亚组比较,冠状动脉管腔CT值、图像噪声、信噪比、对比噪声比、冠状动脉整体主观平均评分等主、客观图像质量差异均无统计学意义(P>0.05)。双低剂量组中心率≤70次/min、BMI>25亚组与常规剂量组对应的亚组比较,冠状动脉管腔CT值、冠状动脉整体主观平均评分差异无统计学意义(P>0.05),而双低剂量组的图像噪声、信噪比、对比噪声比等图像质量评价指标显著差于常规剂量组(P<0.01或0.05);心率>70次/min,BMI>25亚组间比较,双低剂量组的主、客观图像质量评价指标均显著差于常规剂量组(P<0.01或0.05)。结论在老年人中,BMI对低管电压、低对比剂的双低剂量CCTA检查图像质量的影响较大。BMI≤25的老年病人适合应用双低剂量CCTA检查。