Pulmonary Perfusion Research Articles

THROMBOLYTIC AND ANTICOAGULANT THERAPY FOR PULMONARY EMBOLISM: AN EFFECT ON PULMONARY PERFUSION (PART 2)

Background.Perfusion scintigraphy reveals perfusion defects in the occlusion of pulmonary vessels of any caliber and makes it possible to quantify pulmonary blood flow disorders, which allows the method to be used for the comparison of the thrombolytic and anticoagulant therapy efficacy in patients with acute pulmonary embolism.Aim of study .To compare the efficacy of thrombolytic and anticoagulant therapy in the treatment of acute pulmonary embolism in the dynamics of pulmonary perfusion disorders.Study Design.A prospective non-randomized study. The quantitative result of pulmonary perfusion deficiency obtained during perfusion scintigraphy was compared in patients with pulmonary embolism treated with thrombolytics or anticoagulants before treatment and in dynamics. The dynamics was evaluated the next day after administration of thrombolytics and on day 4–5 after initiating anticoagulant therapy. Preliminary analysis of these parameters in the group with anticoagulant therapy a day after the start of administration (by analogy with TLT) revealed no statistically significant differences.Description of the method.Radionuclide and CT studies were performed on a hybrid system SPECT/CT “Discovery NM/CT 670” (GE, USA): perfusion was evaluated with 80–120 MBq of Macrotech 99mTc radiopharmaceutical (RP), CT angiography was performed with 70-100 ml of radiopaque substance “Visipaque.” To determine the total perfusion deficiency, each defect of accumulation with an area equal to the segment was taken as a perfusion deficiency of 5% (subsegmental — 2.5%), equal to the lower lobe — 25%, an area equal to the right lung — 55%, the left lung — 45%. Characteristics of the sample.The perfusion scintigraphy was performed in 381 cases out of 503 patients with a diagnosis of pulmonary embolism of high/intermediate risk of early death, treated in the Intensive Care Unit for Surgical Patients from 2011 to 2016. In 166 cases out of 381, thrombolysis was performed; in 215 cases, an anticoagulant was prescribed. The groups did not differ in age and gender composition: 60±16 years; Me 61 (50; 71) and 62±15 years; Me 63 (53; 74); p=0.22, Mann-Whitney test; men/women: 73/93 and 89/126; p=0.68, the Fisher test.Results of the study.In 96.1% (366/381), perfusion disorders were observed in both lungs; in 3.9% (15/381) there was a unilateral lesion. The comparison of the treatment efficacy was conducted in 169 patients: in 127 cases the next day after introduction of a thrombolytic and in 42 cases on day 4–5 of anticoagulant therapy. In the group with thrombolysis, the initial perfusion deficiency was statistically significantly higher than in the anticoagulant group: 50±10%; Me 50 (40; 60) vs. 39±10; Me 40 (30; 45); p<0.00001, the Mann–Whitney test. The level of pulmonary hypertension was also higher: the systolic pressure in the pulmonary artery was 56±17 Me 54 (45, 68) versus 40±24 Me 40 (22; 56); p<0.00001, the Mann–Whitney test. As a result of treatment, the perfusion deficiency statistically significantly decreased in both groups: in the group with TLT from 50±10%, Me 50 (40; 60) to 26±14%; Me 25 (15; 35); p<0.00000.1, Wilcoxon test; and in the treatment with anticoagulant it decreased from 39±10%, Me 40 (30; 45) to 23±15%; Me 15 (15; 30); p<0.0001, Wilcoxon test. In the TLT group, the perfusion disorders regression was stronger compared to ACT and was registered the next day after administration of a thrombolytic: the standardized effect Es=2.0 and Es=1.2. In the treatment with anticoagulants, statistically significant differences were detected only on day 4–5 from the beginning of its administration. The study power for both groups was 1.00. After thrombolysis the systolic pressure in the pulmonary artery decreased statistically significantly within the next 24 hours: from 56±17 mmHg, Me 54 (45, 68) to 36±14 mmHg, Me 35 (25; 43); p=0.0002, Wilcoxon test; Es=1.3; P=1.00. With anticoagulant treatment, no statistically significant changes in pulmonary arterial pressure occurred 4-5 days after the initiation of treatment: 40±24 mmHg, Me 40 (22; 56) and 50±31 mm Hg, Me 48 (30; 58) ); p=0.72, Wilcoxon test.Conclusion.The advantage of thrombolysis over anticoagulant therapy was the ability to improve pulmonary blood flow, reduce pulmonary hypertension, and stabilize the patients’ condition quickly. Anticoagulant therapy did not allow this effect to be achieved in a short time: the statistically significant reduction in pulmonary perfusion deficiency occurred only on day 4–5 of treatment and was less significant; the statistically significant regression of pulmonary hypertension did not occur at that time.

Balloon Pulmonary Angioplasty for Chronic Thromboembolic Pulmonary Hypertension.

Chronic thromboembolic pulmonary hypertension (CTEPH) is a potentially lethal outcome of pulmonary embolism. Balloon pulmonary angioplasty (BPA) is aimed at improving pulmonary perfusion and pulmonary hemodynamics and has gained a lot of interest recently in patients either unsuitable for or refractory to surgical pulmonary endarterectomy. This article outlines the clinical features and diagnostic criteria, imaging evaluation, current medical and surgical treatment options for CTEPH. BPA is discussed in detail, focusing on the rationale, patient selection, technical details, post-procedural care and outcomes.

Two Cases of Pulmonary Embolectomy Using Retrograde Pulmonary Perfusion for Acute Pulmonary Thromboembolism

Two Cases of Pulmonary Embolectomy Using Retrograde Pulmonary Perfusion for Acute Pulmonary Thromboembolism

Perfusion defects in pulmonary perfusion iodine maps: Causes and semiology

ObjectiveTo describe the usefulness of dual-energy CT for obtaining pulmonary perfusion maps to provide morphological and functional information in patients with pulmonary embolisms. To review the semiology of perfusion defects due to pulmonary embolism so they can be differentiated from perfusion defects due to other causes: alterations outside the range used in the iodine map caused by other diseases of the lung parenchyma or artifacts. ConclusionCT angiography of the pulmonary arteries is the technique of choice for the diagnosis of pulmonary embolisms. New dual-energy CT scanners are useful for detecting perfusion defects secondary to complete or partial obstruction of pulmonary arteries and is most useful for detecting pulmonary embolisms in subsegmental branches.

In vivo imaging of the pathophysiological changes and neutrophil dynamics in influenza virus-infected mouse lungs

The pathophysiological changes that occur in lungs infected with influenza viruses are poorly understood. Here we established an in vivo imaging system that combines two-photon excitation microscopy and fluorescent influenza viruses of different pathogenicity. This approach allowed us to monitor and correlate several parameters and physiological changes including the spread of infection, pulmonary permeability, pulmonary perfusion speed, number of recruited neutrophils in infected lungs, and neutrophil motion in the lungs of live mice. Several physiological changes were larger and occurred earlier in mice infected with a highly pathogenic H5N1 influenza virus compared with those infected with a mouse-adapted human strain. These findings demonstrate the potential of our in vivo imaging system to provide novel information about the pathophysiological consequences of virus infections.

Lung scintigraphy

The S1 guideline for lung scintigraphy has been updated and extended in order to emphasize the advantages oft the method in detecting acute pulmonary embolism (PE) in the periphery oft the lung (subsegmental PE), in underlying subacute and chronic pulmonary disorders, as well as in detecting chronic LE (CTEPH). Method of choice is ventilation / perfusion (V/P) SPECT or V/P SPECT/CT with even higher specificity. Because of its high sensitivity, a threshold (V/P mismatch in at least one segment or two subsegments) is introduced to avoid overtreatment. In case of a change in the therapeutic approach (observation only instead of anticoaculation) the threshold can be omitted. New data concerning the clinical and therapeutical impact of subsegmental PE are included, the chapters open questions have been extented. Other indications for V/P SPECT (secondary diagnoses, abnormalities in pulmonary perfusion, prediction of postoperative lung function) are presented with new data.

Intervention in Massive Pulmonary Embolus: Catheter Thrombectomy/Thromboaspiration versus Systemic Lysis versus Surgical Thrombectomy.

Massive pulmonary embolus (PE), defined as hemodynamic shock from acute PE, is a life-threatening condition. Deaths from massive PE, especially when unsuspected, occur within minutes to hours of onset and as such prompt intervention can be lifesaving. Acute massive PE patients have traditionally been candidates for treatment with intravenous systemic thrombolysis to improve pulmonary artery pressure, arteriovenous oxygenation, and pulmonary perfusion in an effort to reduce mortality. However, patients with contraindications to systemic thrombolysis or those who have failed thrombolysis may benefit from other techniques including endovascular and surgical embolectomy. This article will review the current medical management as well as catheter-directed therapies and surgical embolectomy in the treatment of patients with massive PE.

Radiologic Aspects of the Diagnosis of Pulmonary Embolism in Pregnancy

Pulmonary embolism in pregnancy is a leading cause of maternal mortality. The clinical presentation is often nonspecific, making imaging essential for accurate diagnosis. After reviewing the literature on the radiologic diagnosis of pulmonary embolism in pregnancy, we concluded that both computed tomography pulmonary angiography and lung perfusion scintigraphy are sensitive with high positive predictive values in the presence of high clinical suspicion, but lung perfusion scintigraphy is recommended given lower maternal breast exposure to ionizing radiation and lower fetal contrast exposure. However, if a chest x-ray is abnormal, computed tomography pulmonary angiography is preferred due to high nondiagnostic rates of lung perfusion scintigraphy.

Regional lung chemotherapy techniques to enable or enhance minimally invasive lung surgery

Great strides occurred in the application of minimally invasive techniques for pulmonary lobectomy for almost all indications including advanced neoplasms. Novel treatments besides systemic chemotherapy might be useful to shrink large tumors to enable video-assisted thoracoscopic surgery (VATS) or to enhance treatments for patients with disseminated or otherwise unresectable disease. Several such regional treatments are under investigation and they include inhaled chemotherapy, direct tumor injection, chemoembolization, bronchial artery infusion (BAI), and pulmonary suffusion. These all have specific advantages and limitations depending on the tumor anatomy, physiology and location. Alternatively, VATS theoretically reduces morbidity for oligometastatic disease regional therapy patients who formerly required thoracotomy for vascular access. Promising experimental work with in-vivo pulmonary perfusion patterned on successful methods learned from lung allograft resuscitation is underway. Some of these strategies (alone or combined with standard therapy) are reproducible with existing clinical expertise and should be tested further in clinical trials. This in order to continue the progress toward reducing the morbidity of local control in patients with advanced malignancy, particularly those who are frail.

A Randomized Comparison of Radiation Therapy Techniques in the Management of Node-Positive Breast Cancer: Primary Outcomes Analysis

Although inverse-planned intensity modulated radiotherapy (IMRT) and deep inspiration breath hold (DIBH) may allow for more conformal dose distributions, it is unknown whether using these technologies reduces cardiac or pulmonary toxicity of breast radiotherapy. A randomized controlled trial compared IMRT-DIBH versus standard, free-breathing, forward-planned, three-dimensional conformal radiotherapy in patients with left-sided, node-positive breast cancer in whom the internal mammary nodal region was targeted. Endpoints included dosimetric parameters and changes in pulmonary and cardiac perfusion and function, measured by single photon emission computed tomography (SPECT) scans and pulmonary function testing performed at baseline and 1year post treatment. Of 62 patients randomized, 54 who completed all follow-up procedures were analyzed. Mean doses to the ipsilateral lung, left ventricle, whole heart, and left anterior descending coronary artery were lower with IMRT-DIBH; the percent of left ventricle receiving ≥5Gy averaged 15.8% with standard radiotherapy and 5.6% with IMRT-DIBH (P<.001). SPECT revealed no differences in perfusion defects in the left anterior descending coronary artery territory, the study's primary endpoint, but did reveal statistically significant differences (P=.02) in left ventricular ejection fraction (LVEF), a secondary endpoint. No differences were found for lung perfusion or function. The small but statistically significant benefit in preservation of cardiac LVEF observed here should motivate future studies that include LVEF as a potentially meaningful endpoint. Future studies should disaggregate the impact of IMRT from that of DIBH. Clinical practice should recognize the importance of minimizing cardiac dose, even when already low in comparison to historical levels.

Treatment Effect of Balloon Pulmonary Angioplasty in Chronic Thromboembolic Pulmonary Hypertension Quantified by Automatic Comparative Imaging in Computed Tomography Pulmonary Angiography.

Balloon pulmonary angioplasty (BPA) in patients with inoperable chronic thromboembolic pulmonary hypertension (CTEPH) can have variable outcomes. To gain more insight into this variation, we designed a method for visualizing and quantifying changes in pulmonary perfusion by automatically comparing computed tomography (CT) pulmonary angiography before and after BPA treatment. We validated these quantifications of perfusion changes against hemodynamic changes measured with right-sided heart catheterization. We studied 14 consecutive CTEPH patients (12 women; age, 70.5 ± 24), who underwent CT pulmonary angiography and right-sided heart catheterization, before and after BPA. Posttreatment images were registered to pretreatment CT scans (using the Elastix toolbox) to obtain corresponding locations. Pulmonary vascular trees and their centerlines were detected using a graph cuts method and a distance transform method, respectively. Areas distal from vessels were defined as pulmonary parenchyma. Subsequently, the density changes within the vascular centerlines and parenchymal areas were calculated and corrected for inspiration level differences. For visualization, the densitometric changes were displayed in color-coded overlays. For quantification, the median and interquartile range of the density changes in the vascular and parenchymal areas (ΔVD and ΔPD) were calculated. The recorded changes in hemodynamic parameters, including changes in systolic, diastolic, and mean pulmonary artery pressure (ΔsPAP, ΔdPAP, and ΔmPAP, respectively) and vascular resistance (ΔPVR), were used as reference assessments of the treatment effect. Spearman correlation coefficients were employed to investigate the correlations between changes in perfusion and hemodynamic changes. Comparative imaging maps showed distinct patterns in perfusion changes among patients. Within pulmonary vessels, the interquartile range of ΔVD correlated significantly with ΔsPAP (R = -0.58, P = 0.03), ΔdPAP (R = -0.71, P = 0.005), ΔmPAP (R = -0.71, P = 0.005), and ΔPVR (R = -0.77, P = 0.001). In the parenchyma, the median of ΔPD had significant correlations with ΔdPAP (R = -0.58, P = 0.030) and ΔmPAP (R = -0.59, P = 0.025). Comparative imaging analysis in CTEPH patients offers insight into differences in BPA treatment effect. Quantification of perfusion changes provides noninvasive measures that reflect hemodynamic changes.

Functional morphometry for the estimation of the alveolar surface area in prematurely-born infants

Conventionally, the alveolar surface area (SA) has been measured by using post-mortem morphometry. Such studies have highlighted that SA in prematurely-born infants is markedly smaller when compared to term-born infants as a result of postnatal impairment or arrest of alveolar development. We herein explore how, non-invasive measurements of the ventilation/perfusion ratio (VA/Q) can be used to estimate SA in prematurely-born surviving, convalescent infants. We also compare SA in prematurely-born infants measured at term-corrected age, to term-born infants using previously published datasets of VA/Q. Fick’s first law of diffusion is employed for the conversion of VA/Q measurements to SA values after correcting for differences in pulmonary perfusion, thickness of the respiratory membrane and alveolar-arterial gradient. We report that SA is fivefold smaller in prematurely-born compared to term-born infants. We conclude that non-invasive measurements of VA/Q can be used for the functional estimation of SA which could, in turn, be used as a future outcome measure in respiratory studies of prematurely-born infants.

TEMPORAL AND SPATIAL HETEROGENEITY IN PULMONARY PERFUSION: A MATHEMATICAL MODEL TO PREDICT INTERACTIONS BETWEEN MACRO- AND MICRO-VESSELS IN HEALTH AND DISEASE

Heterogeneity in pulmonary microvascular blood flow (perfusion) provides an early indicator of lung disease or disease susceptibility. However, most computational models of the pulmonary vasculature neglect structural heterogeneities, and are thus not accurate predictors of lung function in disease that is not diffuse (spread evenly through the lung). Models that do incorporate structural heterogeneity have either neglected the temporal dynamics of blood flow, or the structure of the smallest blood vessels. Larger than normal oscillations in pulmonary capillary calibre, high oscillatory stress contribute to disease progression. Hence, a model that captures both spatial and temporal heterogeneity in pulmonary perfusion could provide new insights into the early stages of pulmonary vascular disease. Here, we present a model of the pulmonary vasculature, which captures both flow dynamics, and the anatomic structure of the pulmonary blood vessels from the right to left heart including the micro-vasculature. The model is compared to experimental data in normal lungs. We confirm that spatial heterogeneity in pulmonary perfusion is time-dependent, and predict key features of pulmonary hypertensive disease using a simple implementation of increased vascular stiffness.

Physiologic Factors Influencing the Arterial-To-End-Tidal CO2 Difference and the Alveolar Dead Space Fraction in Spontaneously Breathing Anesthetised Horses.

The arterial to end-tidal CO2 difference (P(a-ET)CO2) and alveolar dead space fraction (VDalvfrac = P(a-ET)CO2/PaCO2), are used to estimate Enghoff’s “pulmonary dead space” (V/QEng), a factor which is also influenced by venous admixture and other pulmonary perfusion abnormalities and thus is not just a measure of dead space as the name suggests. The aim of this experimental study was to evaluate which factors influence these CO2 indices in anesthetized spontaneously breathing horses. Six healthy adult horses were anesthetized in dorsal recumbency breathing spontaneously for 3 h. Data to calculate the CO2 indices (response variables) and dead space variables were measured every 30 min. Bohr’s physiological and alveolar dead space variables, cardiac output (CO), mean pulmonary pressure (MPP), venous admixture , airway dead space, tidal volume, oxygen consumption, and slope III of the volumetric capnogram were evaluated (explanatory variables). Univariate Pearson correlation was first explored for both CO2 indices before V/QEng and the explanatory variables with rho were reported. Multiple linear regression analysis was performed on P(a-ET)CO2 and VDalvfrac assessing which explanatory variables best explained the variance in each response. The simplest, best-fit model was selected based on the maximum adjusted R2 and smallest Mallow’s p (Cp). The R2 of the selected model, representing how much of the variance in the response could be explained by the selected variables, was reported. The highest correlation was found with the alveolar part of V/QEng to alveolar tidal volume ratio for both, P(a-ET)CO2 (r = 0.899) and VDalvfrac (r = 0.938). Venous admixture and CO best explained P(a-ET)CO2 (R2 = 0.752; Cp = 4.372) and VDalvfrac (R2 = 0.711; Cp = 9.915). Adding MPP (P(a-ET)CO2) and airway dead space (VDalvfrac) to the models improved them only marginally. No “real” dead space variables from Bohr’s equation contributed to the explanation of the variance of the two CO2 indices. P(a-ET)CO2 and VDalvfrac were closely associated with the alveolar part of V/QEng and as such, were also influenced by variables representing a dysfunctional pulmonary perfusion. Neither P(a-ET)CO2 nor VDalvfrac should be considered pulmonary dead space, but used as global indices of V/Q mismatching under the described conditions.

Reliability and Physiological Interpretation of Pulmonary Gas Exchange by "Circulatory Equivalents" in Chronic Heart Failure.

BackgroundPeak ratios of pulmonary gas‐exchange to ventilation during exercise (V˙O2/V˙E and V˙CO2/V˙E, termed “circulatory equivalents”) are sensitive to heart failure (HF) severity, likely reflecting low and/or poorly distributed pulmonary perfusion. We tested whether peak V˙O2/V˙E and V˙CO2/V˙E would: (1) distinguish HF patients from controls; (2) be independent of incremental exercise protocol; and (3) correlate with lactate threshold (LT) and ventilatory compensation point (VCP), respectively.Methods and ResultsTwenty‐four HF patients (61±11 years) with reduced ejection fraction (31±8%) and 11 controls (63±7 years) performed ramp‐incremental cycle ergometry. Eighteen HF patients also performed slow (5±1 W/min), medium (9±4 W/min), and fast (19±6 W/min) ramps. Peak V˙O2/V˙E and V˙CO2/V˙E from X‐Y plot, and LT and VCP from 9‐panel plot, were determined by 2 independent, blinded, assessors. Peak V˙O2/V˙E (31.2±4.4 versus 41.8±4.8 mL/L; P<0.0001) and V˙CO2/V˙E (29.3±3.0 versus 36.9±4.0 mL/L; P<0.0001) were lower in HF than controls. Within individuals, there was no difference across 3 ramp rates in peak V˙O2/V˙E (P=0.62) or V˙CO2/V˙E (P=0.97). Coefficient of variation (CV) in peak V˙O2/V˙E was lower than for LT (5.1±2.1% versus 8.2±3.7%; P=0.014), and coefficient of variation in peak V˙CO2/V˙E was lower than for VCP (3.3±1.8% versus 8.7±4.2%; P<0.001). In all participants, peak V˙O2/V˙E was correlated with, but occurred earlier than, LT (r 2=0.94; mean bias, −0.11 L/min), and peak V˙CO2/V˙E was correlated with, but occurred earlier than, VCP (r 2=0.98; mean bias −0.08 L/min).ConclusionsPeak circulatory equivalents during exercise are strongly associated with (but not identical to) LT and VCP. Peak circulatory equivalents are reliable, objective, effort‐independent indices of gas‐exchange abnormality in HF.

Kartagener syndrome associated with bronchopulmonary dysplasia and complicated by obstructive granulomatous bronchiolitis in children

The rarity of Kartagener syndrome, as well as the presence of structural malformative changes associated with the progressive development of granulomatous bronchiolitis, was considered appropriate for the presentation of a clinical case with unfavorable prognosis. Analyzing the clinical laboratory, diagnostic imaging and histopathological results, the authors have concluded that computed tomography data, pulmonary perfusion disturbances found at pulmonary scintigraphy along with progressive deterioration of the pulmonary ventilation function allow identifing and adequately assessing the severity of structural-functional bronchopulmonary changes in children with Kartagener syndrome. The evolution and severity of obstructive syndrome in Kartagener syndrome are determined by the development of structural changes in bronchial-alveolar peripheral airway segments, which together with interstitial inflammatory changes, progressive pneumofibrosis and development of pulmonary hypertension have unfavorable consequences on the evolution and prognosis of the disease. The coexistence of pulmonary dysplasia can be considered as an aggravating factor in the development of Kartagener syndrome in children.

Bilateral breast uptake of 99Tcm-MAA in pulmonary perfusion imaging: a case report

Bilateral breast uptake of 99Tcm-MAA in pulmonary perfusion imaging: a case report

Use of the d-dimer for Detecting Pulmonary Embolism in the Emergency Department

BackgroundAssessment for pulmonary embolism (PE) in the emergency department (ED) remains complex, involving clinical decision tools, blood tests, and imaging. ObjectiveOur objective was to examine the test characteristics of the high-sensitivity d-dimer for the diagnosis of PE at our institution and evaluate use of the d-dimer and factors associated with a falsely elevated d-dimer. MethodsWe retrospectively collected data on adult patients evaluated with a d-dimer and computed tomography (CT) pulmonary angiogram or ventilation perfusion scan at two EDs between June 4, 2012 and March 30, 2016. We collected symptoms (dyspnea, unilateral leg swelling, hemoptysis), vital signs, and medical and social history (cancer, recent surgery, medications, history of deep vein thrombosis or PE, chronic obstructive pulmonary disease, smoking). We calculated test characteristics, including sensitivity, specificity, and likelihood ratios for the assay using conventional threshold and with age adjustment, and performed a univariate analysis. ResultsWe found 3523 unique visits with d-dimer and imaging, detecting 198 PE. Imaging was pursued on 1270 patients with negative d-dimers, revealing 9 false negatives, and d-dimer was sent on 596 patients for whom negative Pulmonary Embolism Rule-Out Criteria (PERC) were documented with 2% subsequent radiographic detection of PE. The d-dimer showed a sensitivity of 95.7% (95% confidence interval [CI] 91–98%), specificity of 40.0% (95% CI 38–42%), negative likelihood ratio of 0.11 (95% CI 0.06–0.21), and positive likelihood ratio of 1.59 (95% CI 1.53–1.66) for the radiographic detection of PE. With age adjustment, 347 of the 2253 CT scans that were pursued in patients older than 50 years with an elevated d-dimer could have been avoided without missing any additional PE. Many risk factors, such as age, history of PE, recent surgery, shortness of breath, tachycardia and hypoxia, elevated the d-dimer, regardless of the presence of PE. ConclusionsMany patients with negative d-dimer and PERC still received imaging. Our data support the use of age adjustment, and perhaps adjustment for other factors seen in patients evaluated for PE.

Risk of post-operative venous thromboembolism in patients with meningioma.

The surgical resection of meningiomas can be complicated by venous thromboembolism (VTE) in the post-operative period, but the exact incidence of this event is not known. Aim of this study was to assess the occurrence of VTE in patients operated for meningioma who underwent a post-operative clinical and objective screening for VTE. Patients undergoing meningioma resection between 2000 and 2010 who accepted to be investigated for VTE in the post-operative period were included in the study. The screening included daily clinical assessment, pulmonary perfusion scintigraphy (Q-SCAN) on day 2 and venous compression ultrasonography (CUS) of the lower limbs within day 7. The univariate and multivariate statistical analysis of risk factors for VTE included sex, age, presence of comorbidities, pre- and post-operative Karnofsky Performance scale (KPS), post-operative neurological worsening and post-operative walking ability. Two-hundred and seventy-five patients were included in the study. VTE was diagnosed in 82 patients (29.8%). Univariate analysis revealed that age ≥ 65 years, cardiovascular comorbidities, pre- and post-operative KPS < 80/100, post-operative neurological worsening and impaired post-operative walking ability were significantly associated with VTE. Multivariate analysis confirmed only age ≥ 65years (p = 0.011) and post-operative KPS < 80/100 (p = 0.002) as independent risk factors for VTE. Patients operated for meningioma have a 30% risk of VTE. Age ≥ 65years and post-operative KPS < 80 were independent risk factors for VTE.

Pre-operative quantification of pulmonary function using hybrid-SPECT/low-dose-CT: A pilot study

RationalePre-operative lobar function is estimated by scintigraphy in patients with pulmonary malignancies and compromised function. This study compared the lobar perfusion determined by scintigraphy (PS) with data from SPECT/low-dose-CT (SPECT/ldCT) analyzed manually and semi-automatic. MethodsRetrospective analysis on 39 patients (m/f = 25/14; age: 72.5 [22–89] years) with indication for pulmonary perfusion scintigraphy. Imaging was performed using SPECT/ldCT. Data was analyzed manually and by semi-automatic software. Readers’ confidence in 3D-segmentation was scored by two independent readers. Interrater agreement was calculated. In addition, Spearman’s rank correlation and Wilcoxon’s test were used. ResultsResults from PS differed significantly from SPECT/ldCT processed manually or semi-automatically in 4/5 lobes (total difference ≤21.6%; rho ≥0.44) and in 3/5 (total difference 21.6%; rho ≥0.37), respectively. Readers’ confidence in 3D-segmentation showed a perfect interrater agreement (κ = 0.98). ConclusionQuantification of lobar perfusion by SPECT/ldCT differs significantly from planar scintigraphy (e.g., with potential influence on therapy). The semi-automatic software analysis provides an applicable methodology.