The role of helical CT in the diagnostic work-up for pulmonary embolism

The clinical diagnosis of pulmonary embolism remains an important challenge despite the multitude of imaging modalities and variety of diagnostic schemes available. Contrast-enhanced helical CT has recently gained favor as an alternative primary imaging modality in the noninvasive diagnosis of pulmonary embolism. This essay reviews the role of helical CT in diagnostic work-up for pulmonary embolism with special emphasis on scan interpretation and diagnostic pitfalls.     

Impact of radiologic imaging on the surgical decision-making process in suspected appendicitis in children

RATIONALE AND OBJECTIVES: To evaluate how the surgeons' decision-making process in appendicitis in children is affected by radiologic imaging. MATERIALS AND METHODS: Prospective study including 593 children with suspected appendicitis was conducted. The surgeon's initial clinical disposition was recorded, designating the patient for operation, observation, or discharge. Thereafter, the patients were randomized to undergo either ultrasound only or ultrasound and abdominal computed tomography. The studies were evaluated by radiologists, who indicated if appendicitis was present or not. After radiology was completed, the surgeon re-examined the patient and made the final disposition. The change of disposition pathway was recorded. Final diagnoses were established by means of surgical, histopathologic, and/or clinical follow-up findings. RESULTS: Two hundred forty-four patients had appendicitis. The initial clinical disposition called for 88 operations, 338 observations, and 167 discharges. In total, 347 patients had their treatment plan changed from the initial disposition, resulting in 252 operations, 65 observations, and 276 discharges. In 11 patients, an unnecessary operation was possibly avoided. In 28 patients who turned out to have appendicitis, a possible inappropriate discharge was avoided. Eighteen patients had a false-negative radiologic diagnosis. Of these, 17 underwent surgery because of convincing clinical findings. The difference between the impact on surgeons' decision-making between the two randomized groups was not substantially different. The negative appendectomy rate was 3.7%. CONCLUSION: Radiologic imaging with ultrasound and/or computed tomography provides valuable guidance whether a patient should be discharged, observed, or given surgical treatment, leading to beneficial changes in management plan. Still, false-negative results may occur and a close clinical re-examination is of utmost importance for the appropriate final decision.     

医院船海外医疗服务期间重症监护病房的感染控制与管理

目的总结参加"和谐使命-2014"海外医疗服务的经验,探索加强医院船重症监护病房感染控制的有效途径和管理措施。方法对医院船重症监护病房存在的感染控制方面问题进行分析,针对性制定出相应的感染控制措施,并在"和谐使命-2014"任务执行过程中付诸实施。结果整个任务期间,医院船重症监护病房收治患者共计119例;其中,1例为艾滋病、梅毒、丙型病毒性肝炎三重感染患者,1例为严重产后感染患者,1例为急性重症胃肠炎患者,2例为肺部感染患者。整个治疗过程顺利,没有出现任何院内感染或感染播散病例。结论对医院船重症监护病房存在的感染控制问题,可通过成立感染控制小组、建立相对隔离措施、加强管理防护等措施加以改进。     

Chest roentgenology in the intensive care unit: an overview

Chest roentgenology in the intensive care unit is a real challenge for the general radiologist. Beyond the basic disease, the critically ill is at risk for developing specific cardiopulmonary disorders, all presenting as chest opacities, their diagnosis often being impossible if based only on the radiological aspect. To make things harder, their appearance can vary with the subject's position and the mechanical ventilation. Patients require a continuous monitoring of the vital functions and their mechanical and pharmacological support, for which they are connected to different instruments. The radiologist should know the normal position of these devices, and promptly recognize when they are misplaced or when complications from their insertion occurred. Our aim is to suggest for each of the above-mentioned conditions a guideline of interpretation based not only on the radiological aspect and distribution of the lesions, but also on the physiopathological and clinical grounds. Received 19 August 1996; Revision received 28 November 1996; Accepted: 6 January 1997     

Improved visualization of tubes and lines in portable intensive care unit radiographs: a study comparing a new approach to the standard approach

Tube and line interpretation in portable chest radiographs was assessed using a new visualization method. When using the new method, radiologists' interpretation time was reduced by 30% vs. standard modality processing and window and level (23 vs. 33 s). For pulmonary ICU physicians, reading time was essentially unchanged. There was more than a 50% reduction in the use of inferential language in the dictation for both reader groups when using the new method, suggesting greater interpretation confidence.     

Diaphragmatic and lung ultrasound application as new predictive indices for the weaning process in ICU patients

Objective

To assess whether the diaphragmatic and lung ultrasound (US) can be used as additive new parameters for the weaning process in intensive care units (ICU) patients in comparison to the traditional weaning parameters.

Role of high resolution ultrasonography in diagnosing septic hip arthritis in premature neonates admitted to the neonatal intensive care unit

Aim

The aim of this study is to evaluate the role of high resolution ultrasonography (HRUS) of the hip in premature neonates admitted to the neonatal intensive care unit (NICU) in diagnosis of septic hip arthritis.

Cumulative radiation exposure from diagnostic imaging in intensive care unit patients

AIM:To quantify cumulative effective dose of intensive care unit(ICU)patients attributable to diagnostic imaging.METHODS:This was a prospective,interdisciplinary study conducted in the ICU of a large tertiary referral and level 1 trauma center.Demographic and clinical data including age,gender,date of ICU admission,primary reason for ICU admission,APACHE Ⅱ score,length of stay,number of days intubated,date of death or discharge,and re-admission data was collected on all patients admitted over a 1-year period.The overall radiation exposure was quantified by the cumulative effective radiation dose(CED)in millisieverts(mS v)and calculated using reference effective doses published by the United Kingdom National Radiation Protection Board.Pediatric patients were selected for subgroupanalysis.RESULTS:A total of 2737 studies were performedin 421 patients.The total CED was 1704 m Sv with a median CED of 1.5 mS v(IQR 0.04-6.6 mS v).Total CED in pediatric patients was 74.6 mS v with a median CED of 0.07 mS v(IQR 0.01-4.7 mS v).Chest radiography was the most commonly performed examination accounting for 83% of all studies but only 2.7% of total CED.Computed tomography(CT)accounted for 16% of all studies performed and contributed 97% of total CED.Trauma patients received a statistically significant higher dose [median CED 7.7 mS v(IQR 3.5-13.8 mS v)] than medical [median CED 1.4 m Sv(IQR 0.05-5.4 m Sv)] and surgical [median CED 1.6 mS v(IQR 0.04-7.5 mS v)] patients.Length of stay in ICU [OR = 1.12(95%CI:1.079-1.157)] was identified as an independent predictor of receiving a CED greater than 15 mS v.CONCLUSION:Trauma patients and patients with extended ICU admission times are at increased risk of higher CEDs.CED should be minimized where feasible,especially in young patients.     

A case series of chest imaging manifestation of COVID-19

Coronavirus disease 2019 (COVID-19) is caused by a infection with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2).¹ It started in Wuhan, China, in December 2019, after which quickly spread to many other countries around the world. Chest radiography (CXR) and computed tomography (CT) play key roles in managment and diagnosis of COVID-19. In this case series we are presenting three patients with predominant left-sided changes caused by COVID-19 infection.     

Predictors of image quality of coronary computed tomography in the acute care setting of patients with chest pain

Objective

We aimed to determine predictors of image quality in consecutive patients who underwent coronary computed tomography (CT) for the evaluation of acute chest pain.

Method and materials

We prospectively enrolled patients who presented with chest pain to the emergency department. All subjects underwent contrast-enhanced 64-slice coronary multi-detector CT. Two experienced readers determined overall image quality on a per-patient basis and the prevalence and characteristics of non-evaluable coronary segments on a per-segment basis.

Results

Among 378 subjects (143 women, age: 52.9 ± 11.8 years), 345 (91%) had acceptable overall image quality, while 33 (9%) had poor image quality or were unreadable. In adjusted analysis, patients with diabetes, hypertension and a higher heart rate during the scan were more likely to have exams graded as poor or unreadable (odds ratio [OR]: 2.94, p = 0.02; OR: 2.62, p = 0.03; OR: 1.43, p = 0.02; respectively). Of 6253 coronary segments, 257 (4%) were non-evaluable, most due to severe calcification in combination with motion (35%). The presence of non-evaluable coronary segments was associated with age (OR: 1.08 annually, 95%-confidence interval [CI]: 1.05-1.12, p < 0.001), baseline heart rate (OR: 1.35 per 10 beats/min, 95%-CI: 1.11-1.67, p = 0.003), diabetes, hypertension, and history of coronary artery disease (OR: 4.43, 95%-CI: 1.93-10.17, p < 0.001; OR: 2.27, 95-CI: 1.01-4.73, p = 0.03; OR: 5.12, 95%-CI: 2.0-13.06, p < 0.001; respectively).

Conclusion

Coronary CT permits acceptable image quality in more than 90% of patients with chest pain. Patients with multiple risk factors are more likely to have impaired image quality or non-evaluable coronary segments. These patients may require careful patient preparation and optimization of CT scanning protocols.     

Low-fat angiomyolipoma of the liver studied with contrast-enhanced ultrasound and multidetector computed tomography

We report the case of a 30-year-old woman with persistent pain at the right hypochondrium, relapsing fever, and normal serum tests. Ultrasound showed a hyperechoic inhomogeneous mass; following sulfur hexafluoride injection, uniform enhancement at 14-16 s and rapid wash-out at 26 s was found. Multidetector computed tomography showed an inhomogeneously hypodense mass, with no detectable negative density values, characterized by inhomogeneous enhancement at the arterial phase and wash-out at the portal phase. Histopathology demonstrated a hepithelioid angiomyolipoma with a poor fatty component. This diagnosis should always be considered in the presence of a very rapid wash-out after intravenous contrast injection. However, a hepatocellular carcinoma cannot be excluded and the final diagnosis of low-fat angiomyolipoma must be pathologically proved based on immunohistochemistry.     

Assessment of anatomic relation between pulmonary perfusion and morphology in pulmonary emphysema with breath-hold SPECT-CT fusion images

OBJECTIVE: Anatomic relation between pulmonary perfusion and morphology in pulmonary emphysema was assessed on deep-inspiratory breath-hold (DIBrH) perfusion single-photon emission computed tomography (SPECT)-CT fusion images. METHODS: Subjects were 38 patients with pulmonary emphysema and 11 non-smoker controls, who successfully underwent DIBrH and non-BrH perfusion SPECT using a dual-headed SPECT system during the period between January 2004 and June 2006. DIBrH SPECT was three-dimensionally co-registered with DIBrH CT to comprehend the relationship between lung perfusion defects and CT low attenuation areas (LAA). By comparing the appearance of lung perfusion on DIBrH with non-BrH SPECT, the correlation with the rate constant for the alveolar-capillary transfer of carbon monoxide (DLCO/VA) was compared between perfusion abnormalities on these SPECTs and LAA on CT. RESULTS: DIBrH SPECT provided fairly uniform perfusion in controls, but significantly enhanced perfusion heterogeneity when compared with non-BrH SPECT in pulmonary emphysema patients (P < 0.001). The reliable DIBrH SPECT-CT fusion images confirmed more extended perfusion defects than LAA on CT in majority (73%) of patients. Perfusion abnormalities on DIBrH SPECT were more closely correlated with DLCO/VA than LAA on CT (P < 0.05). CONCLUSIONS: DIBrH SPECT identifies affected lungs with perfusion abnormality better than does non-BrH SPECT in pulmonary emphysema. DIBrH SPECT-CT fusion images are useful for more accurately localizing affected lungs than morphologic CT alone in this disease.     

64层螺旋CT在肺部结节病影像学诊断中的价值

目的分析64层螺旋CT肺部结节病的影像学表现,特别是结节病CT强化后的特征性表现,以提高对本病的认识和诊断水平。方法回顾性分析经病理证实及临床治疗符合诊断标准的21例肺部结节病的CT表现。结果 21例结节病中,肺门、纵隔淋巴结肿大20例,肺内病变18例,其中沿支气管血管束分布及胸膜下肺结节13例,5例有磨玻璃影。结论双肺门对称性淋巴结增大、纵隔淋巴结增大以及沿支气管血管束分布的结节影为结节病的特征性表现。需与胸内恶性淋巴瘤、结核及胸部转移瘤的鉴别,可以从纵隔淋巴结的好发部位,强化方式等方面进行鉴别;另外结节病对激素治疗有效。     

Preliminary study on evaluation of the pancreatic tail observable limit of transabdominal ultrasonography using a position sensor and CT-fusion image

Background and aim

Transabdominal ultrasonography (US) is commonly used for the initial screening of bilio-pancreatic diseases in Asian countries due to its widespread availability, the non-invasiveness and the cost-effectiveness. However, it is considered that US has limits to observe the area, namely the blind area. The observation of the pancreatic tail is particularly difficult. The goal of this study was to examine the pancreatic tail region that cannot be visualized on transverse scanning of the upper abdomen using US with spatial positional information and factors related to visualization, and observation of the tail from the splenic hilum.

Methods

Thirty-nine patients with pancreatic/biliary tract disease underwent CT and US with GPS-like technology and fusion imaging for measurement of the real pancreatic length and the predicted/real unobservable (PU and RU) length of the pancreatic tail. RU from US on transverse scanning and the real pancreatic length were used to determine the unobservable area (UA: RU/the real pancreatic length). Relationships of RU with physical and hematological variables that might influence visualization of the pancreatic tail were investigated.

Results

The real pancreatic length was 160.9 ± 16.4 mm, RU was 41.0 ± 17.8 mm, and UA was 25.3 ± 10.4%. RU was correlated with BMI (R = 0.446, P = 0.004) and waist circumferences (R = 0.354, P = 0.027), and strongly correlated with PU (R = 0.788, P < 0.001). The pancreatic tail was visible from the splenic hilum in 22 (56%) subjects and was completely identified in 13 (33%) subjects.

Conclusions

Combined GPS-like technology with fusion imaging was useful for the objective estimation of the pancreatic blind area.     

Multi-detector computed tomography angiography of the hepatic artery in liver transplant recipients

Purpose: To evaluate the ability of multi-detector row computed tomography angiography (CTA) in detecting hepatic artery complications in the follow-up of liver transplant patients, performing volume-rendering as reconstruction technique.

Material and Methods: The anatomy of hepatic artery was studied in 27 liver transplant recipients with a four-row CT scanner using the following parameters: collimation, 1 mm; slice width, 1 mm; table feed, 6-8 mm/s; spiral reconstruction time, 0.5 s; reconstruction interval, 0.5 mm; mAs, 160; kVp, 120. Before the study, the patients received 1000 ml of water as oral contrast agent to produce negative contrast in the stomach and the small bowel. A non-ionic contrast medium was infused intravenously at a rate of 5 ml/s with a bolus tracking system. Volume-rendering of hepatic artery was performed with the 3D Virtuoso software.

Results: The celiac trunk, the hepatic artery, and the right and left hepatic arteries were successfully displayed in high detail in all patients. Side branches, including small collaterals, and hepatic artery anastomosis could also be readily visualized. Volume-rendered CTA detected six hepatic artery stenoses, two hepatic artery thromboses, and two intrahepatic pseudoaneurysms. In two cases, CT detected hepatic artery stenosis with a diameter reduction of less than 50%, while digital subtraction angiography showed a normal artery.

Conclusion: Volume-rendered multi-detector CTA is a promising non-invasive technique, since it allows images of high quality to be generated with excellent anatomical visualization of the hepatic artery and its complications in liver transplant recipients.     

Differences in diagnostic evaluation and clinical outcomes in the care of patients with chest pain based on admitting service: The benefits of a dedicated chest pain unit

Background  Chest pain is one of the most common complaints of patients presenting at emergency departments. However, the most appropriate diagnostic evaluation for patients with chest pain but without acute coronary syndrome remains controversial, and differs greatly among institutions and physicians. At our institution, patients with chest pain can be admitted to an internist-run hospitalist service, a private attending service, or a cardiologist-run Chest Pain Unit. The goal of the present study was to compare the management and outcomes of patients admitted with chest pain based on admitting service. Methods  The charts of 750 patients (250 consecutive patients per service) with a discharge diagnosis of chest pain were studied retrospectively. Results  Patients admitted to the Chest Pain Unit were younger and had a lower prevalence of known coronary artery disease, hypertension, or diabetes, but a similar prevalence of other risk factors compared with the other groups. Sixty percent of the patients in the Chest Pain Unit underwent stress myocardial perfusion imaging as their primary diagnostic modality (vs 22% and 12% of patients in the hospitalist and private services, respectively; P<.001). In contrast, 35% of the patients admitted to the hospitalist service underwent rest echocardiography (vs 8% and 17% of patients in the Chest Pain Unit and private services, respectively; P<.001). Finally, 47% of the patients in the private service underwent coronary angiography as their primary diagnostic modality (vs 6% and 10% of patients in the Chest Pain Unit and hospitalist services, respectively; P<.001). The length of stay was shortest for patients in the Chest Pain Unit (1.4±1.2 days vs 3.9±3.4 days and 3.5±3.6 days in the hospitalist and private services, respectively; P<.001), even when corrected for patient age and number of risk factors. Readmission within 6 months was lowest for patients in the Chest Pain Unit (4.4% vs 17.6% and 15.2% in the hospitalist and private services, respectively; P<.001). Conclusions  The results of this study demonstrate that a highly protocolized chest pain unit, using myocardial perfusion imaging as primary diagnostic modality, results in a decreased length of stay and readmission rate.     

MRI findings of epipericardial fat necrosis: As a rare cause of acute chest pain in a healthy man

Epipericardial fat necrosis (EPFN) is a rare, benign cause of acute chest pain imitating symptoms of life-threatening diseases, such as acute coronary syndrome. Here We report a 37-year-old, healthy male presented to the emergency department (ED) with sudden-onset pleuritic chest pain after an isometric physical training. Initial cardiac workup included ECG, echocardiography was unremarkable, but diagnosis of an inflammatory process that involved the epipericardial fat tissue surrounding the heart was made by showing encapsulated fatty lesion, enhanced adjacent parietal pericardium using of contrast‐enhanced magnetic resonance imaging (MRI). Magnetic resonance imaging would help physicians to differentiate EPFN from severe and life-treating conditions.     

新开综合ICU近2年死亡病例统计分析

目的：回顾新开重症监护病房（Icu）死亡病例的年龄、性别构成、死亡原因构成及病死率等情况,为今后提高我院ICU的收治水平提供参考依据。方法：记录患者一般资料、死亡原因、治疗以及转归等情况,采用回顾性方法进行分析。结果：2年来总体死亡病例83例,中位年龄71．0[62．0—81．0]岁,主要分布于60—79岁年龄组。男：女=1．96：1。急性生理和慢性健康评分II（APACHEII）评分中位数32．0[27．0,38．01。死亡原因排前三位的是心脑血管病32例（38．6％）,呼吸系统疾病17例（20．5％）,多器官功能不全16例（19．3％）。总的住院病死率为22．4％。老年前期纽、老年纽、高龄组住院病死率分别为15．0％,23．9％,31．1％,随年龄有逐渐增加的趋势（x^2=7．14,P〈0．01）。急诊转入纽、会诊转入组、术后转入纽病死率分别为48．1％,33．1％,5．3％,急诊转入组病例病死率最高（x^2=58．04,JP〈0．01）。结论：我院新开综合ICU死亡病例以老年组人群分布最多,以男性多见,死亡原因以心脑血管病、呼吸系统疾病、多器官功能不全为主。加强老年患者心脑血管疾病、严重感染和多器官功能不全的防治是我院ICU未来降低病死率应该重点主抓的环节。     

多层螺旋CT与超声诊断胡桃夹现象的价值

 目的 探讨多层螺旋CT(multi-slice spiral CT,MSCT)和超声(ultrasonography,US)诊断胡桃夹现象(nutcracker phenomenon,NCP)的价值。方法 回顾性分析行腹部MSCT和US患者的影像资料,选取证实为NCP的患者30例为观察组,随机抽取因其他原因行腹部MSCT和US检查且无NCP的30例患者为对照组。对两组患者腹主动脉(AA)和肠系膜上动脉(SMA)的夹角(AMA)、左肾静脉(LRV)近肾门扩张处内径(DD)和峰值流速(PVd)、夹角段LRV最窄处内径(DN)和峰值流速(PVn)等,进行相关统计学分析。结果 MSCT和US均可对AMA、DD、DN进行准确测量,且独立检查方式下对比观察组与对照组,差异有统计学意义 (P<0.05),两种检查方式的单因素对比差异无统计学意义 (P>0.05)。US可测PVd、PVn,观察组和对照组数据具有明显差异(P<0.05)。观察组发现侧支循环扩张增粗12例,十二指肠受压7例,左肾体积增大5例,左肾皮质CT增强密度减低3例。结论 MSCT和US是诊断NCP的主要手段,但MSCT对NCP患者伴随征象诊断更具有优势。     

Pulmonary nodule detection on MDCT images: evaluation of diagnostic performance using thin axial images,maximum intensity projections,and computer-assisted detection

This study aimed at evaluating the diagnostic benefits of maximum intensity projections (MIP) and a commercially available computed-assisted detection system (CAD) for the detection of pulmonary nodules on MDCT as compared with standard 1-mm images on lung cancer screening material. Thirty subjects were randomly selected from our database. Three radiologists independently reviewed three types of images: axial 1-mm images, axial MIP slabs, and CAD system detections. Two independent experienced chest radiologists decided which were true-positive nodules. Two hundred eighty-five nodules ≥1 mm were identified as true-positive by consensus of two independent chest radiologists. The detection rates of the three independent observers with 1-mm axial images were 22 ± 4.8%, 30 ± 5.3%, and 47 ± 2.8%; with MIP: 33 ± 5.4%, 39 ± 5.7%, and 45 ± 5.8%; and with CAD: 35 ± 5.6%, 36 ± 5.6%, and 36 ± 5.6%. There was a reading technique effect on the observers’ sensitivity for nodule detection: sensitivities with MIP were higher than with 1-mm images or CAD for all nodules (F-values = 0.046). For nodules ≥3 mm, readers’ sensitivities were higher with 1-mm images or MIP than with CAD (p < 0.0001). CAD was the most and MIP the less time-consuming technique (p < 0.0001). MIP and CAD reduced the number of overlooked small nodules. As MIP is more sensitive and less time consuming than the CAD we used, we recommend viewing MIP and 1-mm images for the detection of pulmonary nodules. This study was presented at the ECR 2006.