Assessing the clinical probability of pulmonary embolism.

Clinical assessment is a cornerstone of the recently validated diagnostic strategies for pulmonary embolism (PE). Although the diagnostic yield of individual symptoms, signs, and common laboratory tests is limited, the combination of these variables, either by empirical assessment or by a prediction rule, can be used to express a clinical probability of PE. The latter may serve as pretest probability to predict the probability of PE after further objective testing (posterior or post-test probability). Over the last few years, attempts have been made to develop structured prediction models for PE. In a Canadian multicenter prospective study, the clinical probability of PE was rated as low, intermediate, or high according to a model which included assessment of presenting symptoms and signs, risk factors, and presence or absence of an alternative diagnosis at least as likely as PE. The prevalence of PE in the low, intermediate, and high pretest probability categories was 3, 28, and 78%, respectively. This model relies heavily on the clinician's subjective judgement as to whether an alternative diagnosis is as likely as or more likely than PE, and, as such, it can be hardly standardized. Furthermore, the inherent complexity of the model may limit its applicability in daily clinical practice. Recently, a simple clinical score was developed to stratify outpatients with suspected PE into groups with low, intermediate, or high clinical probability. Logistic regression was used to predict parameters associated with PE. A score =/<4 identified patients with low probability of whom 10% had PE. The prevalence of PE in patients with intermediate (score 5-8) and high probability (score > or = 9) was 38 and 81%, respectively. As opposed to the Canadian model, this clinical score is standardized. The predictor variables identified in the model, however, were derived from a data base of emergency ward patients. This model may, therefore, not be valid in assessing the clinical probability of PE in inpatients. In the PISA-PED study, a clinical diagnostic algorithm was developed which rests on the identification of three relevant clinical symptoms and on their association with electrocardiographic and/or radiographic abnormalities specific for PE. Among patients who, according to the model, had been rated as having a high clinical probability, the prevalence of proven PE was 97%, while it was 3% in those with low probability. The prevalence of PE in patients with intermediate clinical probability was 41%. These results underscore the importance of incorporating the standardized reading of the electrocardiogram and of the chest radiograph into the clinical evaluation of patients with suspected PE. The interpretation of these laboratory data, however, requires experience. Future research is needed to develop standardized models, of varying degree of complexity, which may find application in different clinical settings to predict the probability of PE.     

肺栓塞的多排螺旋CT肺动脉造影诊断

目的探讨多排螺旋CT在肺栓塞诊断中的应用价值。方法对临床怀疑肺动脉栓塞经多排螺旋CT肺动脉造影(MSCTPA)及临床确诊的15例患者临床资料进行回顾性分析。结果15例肺栓塞患者中,14例诊断为肺栓塞,诊断率约93.3%。1035支肺动脉显示849支,显示率82%;肺栓塞130支,占显示肺动脉数的15.3%。其中亚段肺动脉600支中显示438支,显示率73%,栓塞43支占显示亚段肺动脉的9.8%。直接征象包括不同程度的充盈缺损及动脉断面变细,血管腔内密度不均匀减低。充盈缺损分为4种形式:中央性充盈缺损3例呈轨道征,偏侧性充盈缺损9例,附壁性充盈缺损2例,完全性阻塞3例。间接征象包括马赛克征1例,胸膜下楔形梗死灶3例,肺动脉高压5例,出现W esterm ark征8例,胸腔积液6例。结论MSCTPA是诊断肺栓塞快速、安全有效、无创的诊断方法,它将取代肺动脉造影成为肺栓塞诊断的首选手段。     

The radiographic features of rheumatoid arthritis in HLA-B27-positive patients

Radiographs were reviewed in a group of nine patients with classical seropositive rheumatoid arthritis who on tissue typing were found to express the class I HLA-B27 allele. Radiographs were analyzed with regard to whether or not they demonstrated radiographic features of (1) classical rheumatoid arthritis, (2) seronegative arthritis, or (3) mixed features of rheumatoid and seronegative arthritis. Five patients (55%) displayed radiographic features consistent with a diagnosis of rheumatoid arthritis, two patients (22%) showed radiographic features of seronegative disorder (periostitis and sacroiliitis), and two patients (22%) showed a mixed picture with evidence of both rheumatoid arthritis and a seronegative disorder. Thus, the HLA-B27 allele contributed to the radiographic features in 44% of patients with rheumatoid arthritis and associated HLA-B27. Thus, the wide range of findings in our population indicates that the radiographic attributes are not specific enough to constitute a unique subpopulation of patients with rheumatoid arthritits.     

Is physical education an effective way to increase physical activity in children with lower cardiorespiratory fitness?

Several findings revealed the importance of accruing moderate and vigorous physical activity (MVPA) to improve health. Physical education (PE) may play an important role on promoting children's MVPA. However, it remains unknown whether PE might be effective when increasing physical activity (PA) levels in children with lower cardiorespiratory fitness (CRF). Therefore, the aim of this study was to assess children's PA during PE and during days with and without PE with a special focus on CRF status. One hundred and fifty Spanish children and adolescents from 3rd to 12th grade were recruited. PA levels were assessed with GT3X accelerometers. Peak oxygen uptake (VO_2peak) was estimated using a portable breath by breath Metamax 3B. Participants were classified as healthy aerobic fitness (HAF) and unhealthy aerobic fitness (UHAF) according to standardized cut‐off point criteria. During PE, students with HAF accrued more MVPA than those with UHAF (8.7 vs 5.7 min/session; P ≤ 0.001). MVPA was higher on PE days than days without for both UHAF (50.0 vs 42.7 min/day; P ≤ 0.05) and HAF students (56.9 vs 49.4 min/day; P ≤ 0.05). Although less active during PE, students with lower CRF accumulated more MVPA and total PA on PE days than days without PE. An increase in PE days might be a smart policy to raise the recommended PA levels, regardless of CRF status.     

红景天及其复方对小鼠运动能力和能量代谢影响的研究

为探讨红景天及其复方对运动能力和能量代谢的影响，采用小鼠游泳训练模型，观察体重等一般健康状况、游泳耐力、肝脏及肌肉中ＰＡＳ、ＳＤＨ、ＬＤＨ的组织化学反应。结果表明：红景天及其复方能改善训练小鼠整体状况，提高游泳耐力，增强ＳＤＨ、ＬＤＨ活性，促进运动小鼠肝糖元和肌糖元的分解利用和肝糖元的异生。复方红景天采用益气健脾养阴为主的原则组方，其调节整体机能，促进能量代谢，提高运动能力方面的作用有超过单味红景天的趋势。     

Radiosurgery for brain metastases at the Royal Adelaide Hospital: are we treating the right patients?

Although non-randomized data strongly suggest improved outcome from radiosurgery (RS) for brain metastases relative to whole brain radiotherapy (WBRT) alone, selection factors account for much of the observed differences. This retrospective review of the 16 brain metastases patients treated so far with RS at the Royal Adelaide Hospital confirms a median survival of 10.1 months, consistent with recent multi-institutional pooled results and significantly longer than the median survival of 3-6 months typically reported for WBRT alone. The emerging randomized trials comparing surgery, RS and WBRT for brain metastases are reviewed in the context of the Radiation Therapy Oncology Group Recursive Partitioning Analysis prognostic Class concept in order to assess whether we are using this resource intensive technique to treat the 'right' patients. We conclude that it is reasonable to continue our current policy of considering RS primarily for patients of good performance status with solitary brain metastases. We have a flexible approach to adjuvant WBRT which appears to decrease brain relapse, but not improve survival.     

Rheumatic wrist]

The wrist is frequently involved in the course of inflammatory rheumatism. The clinical and radiological features of the arthritis may guide the diagnosis when wrist involvement is isolated. The rheumatoid wrist may associate articular and tendon sheath synovitis, nerve compressions, muscle atrophy and deformities. X-rays reveal increased volume of the soft tissues, followed by cartilaginous destruction. Magnetic resonance imaging may detect the lesions early in their course. RS3PE, rheumatoid arthritis of the elderly, never induces destructive lesions. Still's disease is distinguished from rheumatoid arthritis by the predominant involvement of the radiocarpal and intercarpal joints with relative sparing of the metacarpo-phalangeal and proximal interphalangeal joints. Jaccoud's hand may be observed in the course of lupus with metacarpo-phalangeal dislocation of capsulo-ligamentous origin without cartilaginous destruction. Wrist involvement is often asymmetrical in ankylosing spondylitis. In psoriatic rheumatism, arthritis of the wrist is similar to that observed in rheumatoid arthritis, but demineralization is less common and occurs later and constructive lesions are associated with pinching.     

三维斑点追踪技术评价正常儿童左室短轴的收缩功能的研究

目的：应用三维斑点追踪技术（3D-STI）评价正常儿童左心室短轴各节段的收缩功能。方法选取健康儿童116名,用3D-S T I计算左室短轴各个节段的径向应变、圆周应变、三维应变、径向位移和三维位移以及相应参数的达峰时间,比较不同心肌短轴节段的收缩功能,并分析各项参数和年龄、心率的关系。结果①径向应变、三维应变、径向位移和三维位移从收缩期开始心肌运动曲线迅速增大,收缩末期达到峰值,然后逐渐降低,逐渐恢复到基线;②前间隔基底段的径向应变和三维应变明显高于其他心底节段;③径向应变、三维应变、径向位移和三维位移,从心底水平到心尖水平依次递减;④径向应变和三维应变和年龄心率无关。结论径向应变和三维应变,和年龄心率无关,可以准确评估左心室局部和整体的收缩功能。     

Rapid-sequence phosphorus-31 magnetic resonance spectroscopy of the human heart using a 1.5-T clinical system

PURPOSE: To compare a 'standard' slow phosphorus-31 magnetic resonance spectroscopy (31P-MRS) sequence with two faster sequences in phantoms and healthy volunteers using a 1.5-T clinical system. MATERIAL AND METHODS: Complete 3D localization was performed using a 2D phosphorus chemical-shift imaging sequence in combination with 30-mm axial slice-selective excitation. Two 31P-MRS rapid sequences (RS8-4: 8 x 8 phase-encoding, with an average of 4 acquisitions, and RS16-1: 16 x 16 phase-encoding, 1 acquisition) were compared with the standard sequence (StdP: 16 x 16 phase-encoding, with an average of 8 acquisitions) in phantom and healthy volunteers. RESULTS: Acquisition time for the 31P-MRS procedure with StdP, RS8-4, and RS16-1 in the healthy volunteer studies ranged from 30 to 45, 3 to 5, and 3 to 5 minutes, respectively. Metabolite measurements of healthy volunteers obtained from 31P-MRS using RS8-4 correlated with values obtained using StdP (PCr r2=0.63, P<0.001; ATP r=0.41, P<0.01 and PCr/ATP ratio r2=0.25, P<0.05). There was no correlation between StdP and RS16-1 for either ATP or the PCr/ATP ratio (r2=0.03, P=0.60, and r2=0.11, p=0.26, respectively). Reproducibility (intensity of phosphorus signal) with RS16-1 was worse than that of RS8-4 or StdP. CONCLUSION: 31P-MRS using RS8-4 may be a valid diagnostic tool for patients with cardiac diseases.     

多层螺旋CT诊断地震伤员肺动脉栓塞的初步探讨

目的初步探讨多层螺旋CT扫描在诊断地震伤员肺动脉栓塞（PE）中的价值。方法对23名地震伤员行胸部多层螺旋CT平扫,分析其放射学征象,并在不结合和结合其他临床资料的情况下对有无PE进行前瞻性预测,评价两种情况下诊断PE的灵敏度;对可疑PE的患者加行肺动脉CT造影扫描,明确有无PE。结果23名地震伤员中,有4名（17％）最后诊断为PE。胸部平扫的征象中,垂直于胸膜面的条带状影见于3例PE患者（75％）及3例无PE的患者（15％）（P值=0.04）,紧贴胸膜的肺野外带实变见于3例PE患者（75％）及4例无PE的患者（21％）（P值=0.067）,胸腔积液见于3例PE患者（75％）及3例无PE的患者（15％）（P值=0.04）,而同时出现上述征象见于3例PE的患者（75％）及1例无PE的患者（5％）（P值=0.009）。在未结合其他临床资料的情况下,CT平扫诊断肺动脉栓塞的灵敏度仅为25％,反之可达75％;肺动脉CT造影显示4例患者共17支肺动脉发生栓塞,除1支为肺叶动脉外,其余16支均发生于肺段动脉,表现为完全性充盈缺损,部分性充盈缺损以及“轨道”征。结论地震创伤容易发生肺动脉栓塞,认识肺动脉栓塞的一些辅助征象并密切结合其他临床资料有助于诊断PE,对可疑病例应及时行肺动脉cT造影明确诊断。     

Widening of coronary sinus in CT pulmonary angiography indicates right ventricular dysfunction in patients with acute pulmonary embolism

Objectives  

Right ventricular dysfunction (RVD) may occur in the course of acute pulmonary embolism (PE). Patients with RVD need more intensive treatment, and the prognosis is more severe. The aim of this study was to evaluate the usefulness of the measurement of the coronary sinus in the assessment of RVD in patients with acute PE and to compare it with other indicators of RVD.     

SPECT imaging of pulmonary emboli with radiolabeled thrombus-specific imaging agents

The safe and accurate diagnosis of acute pulmonary embolism (PE) remains challenging, and many PE-related deaths still occur before the detection of PE. Current techniques detect PE as "negative images," ie, the absence of contrast or downstream perfusion. There would be advantages to obtaining "positive images" of PE, by targeting imaging agents to components that are present primarily on thromboemboli. In addition to providing alternative means of diagnosing acute PE, they would also enable acute PE to be distinguished from other types of pulmonary arterial obstruction, such as unresolved intravascular defects attributable to previous PE. Positive images of PE require imaging agents to bind onto target antigens that are present predominantly on thromboemboli. The "D dimer" regions of polymerized fibrin are present in high concentrations on thromboemboli and are sufficiently accessible to binding. (99m)Tc-lableled anti-D-dimer deimmunized monoclonal antibody Fab' fragments (DI-DD-3B6/22-80B3) bind specifically to thromboemboli, with a thrombus: blood labeling ratio that allows scintigraphic detection. Another thrombus-specific imaging agent is (99m)Tc-labeled apcitide, a synthetic peptide that binds with a high affinity and specificity to the glycoprotein IIb/IIIa receptor on the membrane of activated platelets. Both of these agents have enabled the detection of lower extremity deep vein thrombi by planar scintigraphy. However, even highly radiolabeled PEs are difficult to distinguish by planar scintigraphy from the large blood pool in the heart and lungs. The spatial and contrast resolution inherent to single-photon emission computed tomography (SPECT) scanning allow the in situ imaging of pulmonary emboli that have been bound by radiolabeled thrombus-specific imaging agents. Preliminary trials in humans with acute PE have shown that the emboli can be detected after intravenous administration of (99m)Tc-lableled anti-D dimer, followed by SPECT scanning. Although clinical results are still preliminary, it appears that imaging of pulmonary emboli with SPECT, after administration of radiolabeled thrombus-specific antibody fragments, is accurate and clinically feasible.     

The apex angle of the rocker sole affects the posture and gait stability of healthy individuals

BackgroundRocker sole (RS) shoes have been linked to impaired postural control. However, which features of RS design affect balance is unclear.Research questionWhich RS design features affect standing balance and gait stability?MethodsThis study utilized an intervention and cross-over design. Twenty healthy young adults (10 males and 10 females) participated in this study. Standing balance and gait stability were measured using a single force platform and three-dimensional motion analysis system, respectively. The experimental conditions included the control shoe and five RS shoes in the combination of apex position (%) and apex angle (degree) for RS50-95, RS60-95, RS70-95, RS60-70, and RS60-110. The main outcome measures were the area surrounding the maximal rectangular amplitude, mean path length, average displacement of the center of pressure along the lateral and anterior/posterior directions, and maximal center of pressure excursion as the standing balance and lateral margin of stability as the gait stability. Statistical analyses were conducted using a two-way split-plot analysis of variance with repeated measures (with RS design as the within-subject factor and sex as the between-subject factor) and the Bonferroni post hoc test (α = .05).ResultsRegarding the mean path length, RS60-70 was significantly longer than the control shoe, and it showed a significantly increased lateral margin of stability. Thus, RS60-70 was shown to affect standing balance, limit of stability, and gait stability of the frontal plane during gait.SignificanceThese results suggest that the apex angle of the RS design feature affects standing balance and gait stability, and RS60-70 is detrimental to stability. Therefore, when RS with a small apex angle is prescribed, it is necessary to consider the patient’s balance ability.     

A generalized k-sampling scheme for 3D fast spin echo

The phase-encoding scheme can significantly affect the quality of fast spin-echo (FSE) images because the echo amplitude is modulated as a function of the echo position in k-space. The effects of the modulation in two-dimensional FSE imaging include ghosting and blurring artifacts and resolution loss in the phase-encoding (PE) direction. In 3D FSE imaging, the use of two PE directions presents the opportunity for improved PE schemes. A new scheme for assignment of echoes to views in 3D FSE, termed generalized, has been developed. This scheme distributes T(2) effects along both PE directions, allowing considerable flexibility in the selection of blurring artifact appearance. In a set of simulations, phantom experiments, and in vivo experiments, the performance of the generalized PE scheme for 3D FSE imaging was compared with the performance of existing PE schemes. The results demonstrate that the generalized PE scheme can be used to reduce blurring artifacts greatly relative to other PE techniques that are presently in use. This approach to PE can be used to manipulate the blurring artifact appearance and to optimize acquisition time.     

维生素C缓释包衣片的研究

目的：　制备维生素Ｃ缓释包片,考察自制的渗透型丙烯酸树脂与Ｅｕｄｒａｇｉｔ ＲＳ／ＲＬ的一致性及包衣片的稳定性。方法：分别以自制的渗透型丙烯酸树脂和标准样品为薄膜包衣材料,制备维生素Ｃ缓释包衣片,以体外溶出试验,考察二者的缓释性能及所得包衣缓释片的稳定性。结果：转蓝法测定药物溶出度表明,用Ｅｕｄｒａｇｉｔ ＲＬ和ＲＳ包衣的缓释片,其释药速度有明显的差别,但在１０ｈ 内均以零级动力学过程连续释药;自制的ＲＬ和ＲＳ产品达到了国外同类产品的应用性能要求。结论：自制的渗透型缓释材料与标准样品ＥｕｄｒａｇｉｔＲＳ／ＲＬ 基本一致;维生素Ｃ缓释包衣片能延缓药物氧化、增加片剂的稳定性     

Association between partial-volume corrected SUV<Subscript>max</Subscript> and Oncotype DX recurrence score in early-stage,ER-positive/HER2-negative invasive breast cancer

Purpose

Oncotype DX, a 21-gene expression assay, provides a recurrence score (RS) which predicts prognosis and the benefit from adjuvant chemotherapy in patients with early-stage, estrogen receptor-positive (ER-positive), and human epidermal growth factor receptor 2-negative (HER2-negative) invasive breast cancer. However, Oncotype DX tests are expensive and not readily available in all institutions. The purpose of this study was to investigate whether metabolic parameters on ¹⁸F-FDG PET/CT are associated with the Oncotype DX RS and whether ¹⁸F-FDG PET/CT can be used to predict the Oncotype DX RS.

Methods

The study group comprised 38 women with stage I/II, ER-positive/HER2-negative invasive breast cancer who underwent pretreatment ¹⁸F-FDG PET/CT and Oncotype DX testing. On PET/CT, maximum (SUV_max) and average standardized uptake values, metabolic tumor volume, and total lesion glycolysis were measured. Partial volume-corrected SUV_max (PVC-SUV_max) determined using the recovery coefficient method was also evaluated. Oncotype DX RS (0?–?100) was categorized as low (<18), intermediate (18?–?30), or high (≥31). The associations between metabolic parameters and RS were analyzed. Multivariate logistic regression was used to identify significant independent predictors of low versus intermediate-to-high RS.

Results

Of the 38 patients, 22 (58 %) had a low RS, 13 (34 %) had an intermediate RS, and 3 (8 %) had a high RS. In the analysis with 38 index tumors, PVC-SUV_max was higher in tumors in patients with intermediate-to-high RS than in those with low RS (5.68 vs. 4.06; P?=?0.067, marginally significant). High PVC-SUV_max (≥4.96) was significantly associated with intermediate-to-high RS (odds ratio, OR, 10.556; P?=?0.004) in univariate analysis. In multivariate analysis with clinicopathologic factors, PVC-SUV_max ≥4.96 (OR 8.459; P?=?0.013) was a significant independent predictor of intermediate-to-high RS.

Conclusions

High PVC-SUV_max on ¹⁸F-FDG PET/CT was significantly associated with an intermediate-to-high Oncotype DX RS. PVC metabolic parameters on ¹⁸F-FDG PET/CT can be used to predict the Oncotype DX RS in patients with early-stage, ER-positive/HER2-negative breast cancer.

     

Preliminary investigation of computer-aided detection of pulmonary embolism in three-dimensional computed tomography pulmonary angiography images

RATIONALE AND OBJECTIVES: We sought to develop a computer-aided diagnosis (CAD) system for assisting radiologists in the detection of pulmonary embolism (PE) on computed tomography pulmonary angiographic (CTPA) images. MATERIALS AND METHODS: An adaptive three-dimensional (3D) voxel clustering method was developed based on expectation-maximization (EM) analysis to extract vessels from their surrounding tissues. Using a connected component analysis, the vessel tree was reconstructed by tracking the vessel and its branches in 3D space. The tracked vessels were prescreened for suspicious PE areas using a second EM analysis. A rule-based false-positive (FP) reduction method was designed to detect true PE based on the features of PE and vessels. In this preliminary study, 14 patients with positive CTPA for PE were studied. CT scans were performed at 1.25-mm collimation using a GE LightSpeed CT scanner; eight of these patients also had extensive lung parenchymal or pleural disease. One hundred sixty-three emboli were identified by two experienced thoracic radiologists. The emboli identified by the radiologists were used as the "gold standard." For each embolus, the percent diameter occlusion (clot) and conspicuity of embolus (rating of 1 to 5, with 5 being the most conspicuous) were visually estimated. One hundred one emboli were identified in the six patients without lung diseases; 57 were proximal to the subsegmental and 44 were subsegmental. For the eight patients with lung diseases, 62 emboli were identified, of which 37 were proximal to the subsegmental and 25 were subsegmental. A computer-detected volume was counted as true-positive when it overlapped with an embolus volume identified by the radiologists. RESULTS: In the cases without lung diseases, if the PE had a conspicuity of >2 and only partially (20%-80%) occluded the vessel, our method detected 92.0% of proximal emboli and 77.8% of subsegmental emboli, with an average of 18.3 FPs/case. In the cases containing extensive lung disease, 66.7% and 40.0% of the PEs were detected with an average of 11.4 FPs/case under the same conditions. For the 14 PE cases, 13 of them were diagnosed as positive PE cases (case sensitivity was 92.9%). CONCLUSION: This preliminary study indicates that our automated method is a promising approach to CAD of PE on CTPA. Further study is under way to collect a larger data set and to improve the detection accuracy for PE, especially those with <20% or >80% occlusion, and for very subtle PE. A fully developed CAD system is expected to provide a useful aid for PE detection on CTPA.     

16层螺旋CT肺血管造影在肺动脉栓塞诊断中的应用

目的　研究 16层螺旋CT肺血管造影在肺动脉栓塞诊断中的应用价值。方法　使用 16层螺旋CT扫描机 (SiemensSensation 16 )对临床拟诊肺栓塞的 4 9例患者进行前瞻性研究。采用层厚 3mm行胸部增强扫描。利用原始数据行层厚 1mm的轴面及多平面重建 (MPR)。比较层厚 3mm、1mm的轴面图像及MPR图像。结果　CT诊断肺栓塞 4 2例。病变共累及肺动脉 35 2支。对于主肺动脉及肺叶动脉栓塞 ,三种图像检出结果一致。但对于肺段及亚段动脉栓塞 ,层厚 1mm较 3mm显示率高 ,差异有显著意义 (P <0 0 1) ,1mm的MPR较轴面图像显示率高 ,但差异无显著性意义 (P >0 0 5 )。结论　 16层螺旋CT肺血管造影无创、快速、敏感性高 ,应当作为肺栓塞的首选检查方法。     

Three-dimensional selective-scale texture analysis of computed tomography pulmonary angiograms

OBJECTIVES: This feasibility study aims to develop 3-dimensional (3D) selective-scale texture analysis of computed tomography pulmonary angiography to identify texture correlates for ventilated and vascular lung for visual and quantitative assessment of pulmonary disorders with altered vasculature. MATERIALS AND METHODS: Computed tomography pulmonary angiography examinations of 8 patients were considered in this study; 3 had normal lungs, 3 had pulmonary embolism (PE1, PE2, and PE3), 1 had only emphysema (PEmp), whereas the final patient had both emphysema and embolism (PEE). Before texture analysis, an initial automated segmentation procedure to include only the lung parenchyma and generation of isometric volume were carried out. From this segmented volume, ventilated lung and pulmonary vessels were separately selected. Texture analysis comprised 2 stages: 1) volume filtration using 3D Laplacian of Gaussian filter to highlight fine and coarse textures within ventilated and vascular lung, followed by 2) quantification of texture using mean gray-level intensity, entropy and uniformity both globally and at 3 anatomic sections of the lung, ie, anterior, middle, and posterior. Quantification of texture was also performed on the unfiltered computed tomography lung dataset. Volume rendering and image fusion of ventilated and vascular lung texture were employed for visualization. RESULTS: For fine texture quantified as mean gray-level intensity in ventilated lung, a postural gradient compatible with known pulmonary physiology was demonstrated and texture was different in emphysematous lung (PEmp and PEE) when compared with nonemphysematous lung (normals, PE1, PE2, and PE3) consistent with altered ventilation. Coarse texture in vascular lung demonstrated a descending trend in entropy (or ascending trend in uniformity) for normals, followed by embolism only (PE1, PE2, and PE3) and finally for emphysematous lung (PEmp and PEE) suggesting a correlation with degree of vascularity (or perfusion). 3D images of ventilated and vascular lung texture highlighted mismatched and matched defects in patients with pulmonary disorders. CONCLUSIONS: This feasibility study demonstrated that 3D filtered texture analysis can potentially provide correlates for ventilated and vascular lung, which may be useful in the diagnosis of PE in the presence of other causes of altered vascularity.     

Incidental pulmonary embolism in CT scans of oncological patients with metastatic disease undergoing clinical trials: frequency and linkage with onset of disease progression (PE-PD association)

Objectives:We aimed to analyze the association between the onsets of PE and of progressive disease (PD) in CT scans of oncological patients undergoing clinical trials.Methods:We retrospectively searched our oncological clinical trials database (1/2012 - 6/2017). We retrieved patients who underwent protocol baseline and follow-up CT scans. RECIST 1.1 categories of response were calculated for each scan at interpretation. The entire dataset was searched for reports with incidental PE.For patients with incidental PE, we collected all the scans conducted up to and including the scan with PE. For each scan, we retrieved the recorded RECIST 1.1 category. We excluded patients with PE at baseline.The frequency of incidental PE in oncological clinical trial patients was calculated. For patients with incidental PE, we evaluated the association between PE and PD.Results:During the study period, 1,070 patients underwent 3,818 CTs. The total number of follow-up months was 7,292 months. 18 patients developed incidental PE during follow-up. Thus, the frequency of incidental PE in oncological clinical trial patients was 3% per year of follow-up. Patients with incidental PE underwent 60 scans up to development of PE. Of 42 non-baseline scans, 6/6 (100%) PD showed PE, and 5/36 (13.9%) non-PD showed PE, making PE onset associated with PD onset (p < 0.001).Conclusion:In oncological clinical trials, the frequency of incidental PE is 3% per year of follow-up. The onset of incidental PE is linked to the onset of PD.Advances in knowledge:Incidental PE is associated with the onset of disease progression. Radiologists interpret oncological scans should be aware of the association between PE and PD.