New formula for quantification of pleural effusions from computed tomography

Small Hemothoraces Not Drained on Admission: Initial Volume Predicts Need for Intervention

BACKGROUND

Unlike large hemothoraces (HTX), small HTX after blunt trauma may be observed without drainage. We aimed to study if there were risk factors that would predict the need for intervention in initially observed small HTX.

METHODS

A retrospective review of patients with blunt traumatic HTX from 2016 to 2022 was performed. Patients with small HTX (pleural fluid volume <400 mL on admission chest computerized tomography [CT]) were included. Patients were considered as being "initially observed" if there was no intervention for the HTX within 48 hours after admission. Primary outcome was any HTX-related intervention (open, thoracoscopic or percutaneous procedures) occurring after 48 hours and up to 6 months after injury. Univariable and multivariable statistical analyses were employed. A P-value of <.05 was considered significant.

RESULTS

Of 335 patients with HTX, 188 (59.6%) met inclusion criteria. Median (interquartile range) HTX volume was 90 (36-134) ml. One hundred and twenty-seven (68%) were initially observed. Of these, 31 (24%) had the primary outcome. These patients had a larger HTX volume (median, 129 vs 68 mL, P = .0001), and number of rib fractures (median, 7 vs 4, P = .0002) compared to those without the primary outcome. Chest-related readmission occurred in 8 (6%) with a median of 20 days from injury. Of these, 7 required an HTX-related intervention. Logistic regression analysis found that both the number of rib fractures and HTX volume independently predicted the primary outcome.

CONCLUSION

For small HTX initially observed, number of rib fractures and initial volume predicted delayed HTX-related intervention.

Percutaneous thoracostomy with thoracic lavage for traumatic hemothorax: a performance improvement initiative

Objectives

Percutaneously placed small-bore (14 Fr) catheters and pleural lavage have emerged independently as innovative approaches to hemothorax management. This report describes techniques for combining percutaneous thoracostomy with pleural lavage and presents results from a performance improvement series of patients managed with percutaneous thoracostomy with immediate lavage.

Methods

This was a prospective performance improvement series of patients treated at a level 1 trauma center with percutaneous thoracostomy and immediate lavage between April 2021 and May 2023.

Results

Percutaneous thoracostomy with immediate lavage was used to treat nine hemodynamically normal patients with acute hemothorax. Injuries included both blunt and penetrating mechanisms. 56% of patients presented immediately after injury, and 44% presented in a delayed fashion ranging from 2 to 26 days after injury. Median length of stay was 6 days (IQR 6, 9). Seven patients were discharged home in stable condition, one was discharged to an acute rehabilitation facility, and one was discharged to a skilled nursing facility.

Conclusions

Percutaneous thoracostomy with pleural lavage is clinically feasible and effective and warrants further evaluation with a multicenter clinical trial.

Level of evidence

Therapeutic/care management, level V.

CT-based pleural effusion volume estimation formula demonstrates low accuracy and reproducibility for traumatic hemothorax

PURPOSE

We aimed to evaluate the accuracy and reproducibility of the CT-based volume estimation formula V = d2 * h, where d and h represent the maximum depth and height of the effusion, for acute traumatic hemothorax.

MATERIALS & METHODS

Prospectively identified patients with CT showing acute traumatic hemothorax were considered. Volumes were retrospectively estimated using d2 * h, then manually measured on axial images. Subgroup analysis was performed on borderline-sized hemothorax (200-400 mL). Measurements were repeated by three non-radiologists. Bland-Altman analysis was used to assess agreement between the two methods and agreement between raters for each method.

RESULTS

A total of 46 patients (median age 34; 36 men) with hemothorax volume 23-1622 mL (median 191 mL, IQR 99-324 mL) were evaluated. Limits of agreement between estimates and measured volumes were -718 - +842 mL (± 202 mL). Borderline-sized hemothorax (n = 13) limits of agreement were -300 - +121 mL (± 114 mL). Of all hemothorax, 85 % (n = 39/46) were correctly stratified as over or under 300 mL, and of borderline-sized hemothorax, 54 % (n = 7/13). Inter-rater limits of agreement were -251 - +350, -694 - +1019, and -696 - +957 for the estimation formula, respectively, and -124 - +190, -97 - +111, and -96 - +46 for the measured volume.

DISCUSSION

An estimation formula varies with actual hemothorax volume by hundreds of mL. There is low accuracy in stratifying hemothorax volumes close to 300 mL. Variability between raters was substantially higher with the estimation formula than with manual measurements.

Predictors of initial management failure in traumatic hemothorax: A prospective multicenter cohort analysis

BACKGROUND

Traumatic hemothorax is common, and management failure leads to worse outcomes. We sought to determine predictive factors and understand the role of trauma center performance in hemothorax management failure.

METHODS

We prospectively examined initial hemothorax management (observation, pleural drainage, surgery) and failure requiring secondary intervention in 17 trauma centers. We defined hemothorax management failure requiring secondary intervention as thrombolytic administration, tube thoracostomy, image-guided drainage, or surgery after failure of the initial management strategy at the discretion of the treating trauma surgeon. Patient-level predictors of hemothorax management failure requiring secondary intervention were identified for 2 subgroups: initial observation and immediate pleural drainage. Trauma centers were divided into quartiles by hemothorax management failure requiring secondary intervention rate and hierarchical logistic regression quantified variation.

RESULTS

Of 995 hemothoraces in 967 patients, 186 (19%) developed hemothorax management failure requiring secondary intervention. The frequency of hemothorax management failure requiring secondary intervention increased from observation to pleural drainage to surgical intervention (12%, 22%, and 35%, respectively). The number of ribs fractured (odds ratio 1.12 per fracture; 95% confidence interval 1.00-1.26) and pulmonary contusion (odds ratio 2.25, 95% confidence interval 1.03-4.91) predicted hemothorax management failure requiring secondary intervention in the observation subgroup, whereas chest injury severity (odds ratio 1.58; 95% confidence interval 1.17-2.12) and initial hemothorax volume evacuated (odds ratio 1.10 per 100 mL; 95% confidence interval 1.05-1.16) predicted hemothorax management failure requiring secondary intervention after pleural drainage. After adjusting for patient characteristics in the logistic regression model for hemothorax management failure requiring secondary intervention, patients treated at high hemothorax management failure requiring secondary intervention trauma centers were 6 times more likely to undergo an intervention after initial hemothorax management failure than patients treated in low hemothorax management failure requiring secondary intervention trauma centers (odds ratio 6.18, 95% confidence interval 3.41-11.21).

CONCLUSION

Failure of initial management of traumatic hemothorax is common and highly variable across trauma centers. Assessing patient selection for a given management strategy and center-level practices represent opportunities to improve outcomes from traumatic hemothorax.

[Occult and Retained Haemothorax - Recommendations of the Interdisciplinary Thoracic Trauma Task Group of the German Trauma Society (DGU - Section NIS) and the German Society for Thoracic Surgery (DGT)]

The management of occult and retained haemothorax is challenging for all involved in the care of polytrauma patients in terms of diagnosis and treatment. The focus of decision making is preventing sequelae such as pleural empyema and avoiding a trapped lung. An interdisciplinary task force of the German Society for Thoracic Surgery (DGT) and the German Trauma Society (DGU) on thoracic trauma offers recommendations for post-trauma care of patients with occult and/or retained haemothorax, as based on a comprehensive literature review.

Pleural effusion volume in patients with acute pancreatitis: a retrospective study from three acute pancreatitis centers

OBJECTIVE

To assess the value of pleural effusion volume (PEV) quantified on chest computed tomography (CT) in patients with early stage acute pancreatitis (AP).

METHODS

Data of PEV, and C-reactive protein (CRP) levels as well as Ranson, bedside index of severity in acute pancreatitis (BISAP), Marshall, acute physiology and chronic health evaluation II (APACHE II), CT severity index (CTSI), and extra-pancreatic inflammation on computed tomography (EPIC) scores in patients with AP were collected. Duration of hospitalization, severity of AP, infection, procedure, intensive care unit (ICU) admission, organ failure, or death were included as the outcome parameters.

RESULTS

In 465 patients, the mean PEV was 98.8 ± 113.2 mL. PEV showed strong and significant correlations with the CRP levels, duration of hospitalization as well as the Ranson, BISAP, Marshall, APACHE II, CTSI, and EPIC scores (p < .05). PEV demonstrated significant accuracy in predicting severity, infection, procedure, ICU admission, organ failure, and death (p < .05).

CONCLUSION

PEV quantified on chest CT positively associated with the duration of hospitalization, CRP levels, Ranson, BISAP, Marshall, APACHE II, CTSI, and EPIC scores. It can be a reliable radiologic biomarker in predicting severity and clinical outcomes of AP.KEY MESSAGESPleural effusion is a common chest finding in patients with acute pancreatitis.Pleural effusion volume quantified on chest CT examination positively associated with the duration of hospitalization, CRP level, as well as Ranson, BISAP, Marshall, APACHE II, CTSI, and EPIC scoring systems.Pleural effusion volume can be a reliable radiologic biomarker in the prediction of severity and clinical outcomes of acute pancreatitis.

Prevalence, clinical characteristics, and outcome of pleural effusions in ovarian cancer

Objectives

The prevalence, clinical characteristics and prognosis of pleural effusions (PEs) associated with ovarian cancer (OC) have seldom been addressed systematically, as in the current investigation.

Methods

All records of consecutive women with a newly diagnosed OC in our institution over a 13-year period were retrospectively reviewed. Features of PEs on CT scans, pleural fluid analyses, need for definitive therapy of PEs, and the influence of PEs on the overall survival (OS) and progression-free survival (PFS) were evaluated.

Results

PEs were observed in 81 (43%) of 189 women with OC, either at presentation of cancer (55 patients) or during the course of the disease (26 patients). The causes of PEs were malignancy (55.5%), unknown (37%), or surgery-related (7.4%). The sensitivity of the cytologic diagnosis of malignant PEs was 79.1%. Sixty percent of malignant PEs required pleurodesis or indwelling pleural catheters for symptomatic relief. The presence of ascites strongly predicted PE development (odds ratio 43.2). Women with PEs fared much worse compared with those without PEs, in terms of OS (26.7 vs. 90.4 months), PFS (9.8 vs. 55.3 months) and tumor recurrences (86.4 vs. 43%). In multivariate analyses, PE remained as a relevant independent variable associated with poor outcome (hazard ratio 9.73 for OS, and 3.87 for PFS). Notably, PEs small enough to preclude tapping, and thus of unknown origin, had a similar bad prognosis as malignant PEs.

Conclusions

OC patients with PEs experience decreased survival, including those with trace effusions not amenable to tapping.

Predictors of retained hemothorax in trauma: Results of an Eastern Association for the Surgery of Trauma multi-institutional trial

BACKGROUND

The natural history of traumatic hemothorax (HTX) remains unclear. We aimed to describe outcomes of HTX following tube thoracostomy drainage and to delineate factors that predict progression to a retained hemothorax (RH). We hypothesized that initial large-volume HTX predicts the development of an RH.

METHODS

We conducted a prospective, observational, multi-institutional study of adult trauma patients diagnosed with an HTX identified on computed tomography (CT) scan with volumes calculated at time of diagnosis. All patients were managed with tube thoracostomy drainage within 24 hours of presentation. Retained hemothorax was defined as blood-density fluid identified on follow-up CT scan or need for additional intervention after initial tube thoracostomy placement for HTX.

RESULTS

A total of 369 patients who presented with an HTX initially managed with tube thoracostomy drainage were enrolled from 17 trauma centers. Retained hemothorax was identified in 106 patients (28.7%). Patients with RH had a larger median (interquartile range) HTX volume on initial CT compared with no RH (191 [48-431] mL vs. 88 [35-245] mL, p = 0.013) and were more likely to be older with a higher burden of thoracic injury. After controlling for significant differences between groups, RH was independently associated with a larger HTX on presentation, with a 15% increase in risk of RH for each additional 100 mL of HTX on initial CT imaging (odds ratio, 1.15; 95% confidence interval, 1.08-1.21; p < 0.001). Patients with an RH also had higher rates of pneumonia and longer hospital length of stay than those with successful initial management. Retained hemothorax was also associated with worse functional outcomes at discharge and first outpatient follow-up.

CONCLUSION

Larger initial HTX volumes are independently associated with RH, and unsuccessful initial management with tube thoracostomy is associated with worse patient outcomes. Future studies should use this experience to assess a range of options for reducing the risk of unsuccessful initial management.

LEVEL OF EVIDENCE

Therapeutic/care management study, level III.

Facilitating ventilator weaning through rib fixation combined with video-assisted thoracoscopic surgery in severe blunt chest injury with acute respiratory failure

Background

Severe blunt chest injury sometimes induces acute respiratory failure (ARF), requiring ventilator use. We aimed to evaluate the effect of performing rib fixation with the addition of video-assisted thoracoscopic surgery (VATS) on patients with ARF caused by blunt thoracic injury with ventilator dependence.

Methods

This observational study prospectively enrolled patients with multiple bicortical rib fractures with hemothorax caused by severe blunt chest trauma. All patients received positive pressure mechanical ventilation within 24 h after trauma because of ARF. Some patients who received rib fixation with VATS were enrolled as group 1, and the others who received only VATS were designated as group 2. The length of ventilator use was the primary clinical outcome. Rates of pneumonia and length of hospital stay constituted secondary outcomes.

Results

A total of 61 patients were included in this study. The basic demographic characteristics between the two groups exhibited no statistical differences. All patients received operations within 6 days after trauma. The length of ventilator use was shorter in group 1 (3.19 ± 3.37 days vs. 8.05 ± 8.23, P = 0.002). The rate of pneumonia was higher in group 2 (38.1% vs. 75.0%, P = 0.005). The length of hospital stay was much shorter in group 1 (17.76 ± 8.38 days vs. 24.13 ± 9.80, P = 0.011).

Conclusion

Rib fixation combined with VATS could shorten the length of ventilator use and reduce the pneumonia rate in patients with severe chest blunt injury with ARF. Therefore, this operation could shorten the overall length of hospital stay.

The advantages of adding rib fixations during VATS for retained hemothorax in serious blunt chest trauma - A prospective cohort study

BACKGROUND

Serious blunt chest trauma usually induces hemothorax, pneumothorax, and rib fracture. Early video-assisted thoracoscopic surgery (VATS) to evacuate retained hemothorax is one commonly used treatment. In this study, a new strategy was implemented to combine VATS with fractured rib fixation simultaneously.

METHODS

This prospective observational study was performed from January 2013 to April 2018. All patients were aged 18 years or older and had blunt chest trauma with displaced fractures in more than three ribs. No patients had acute respiratory failure within 24 h after trauma. Patients with retained hemothorax who received VATS constituted the study cohort. Subsequently, patients who received rib fixation during VATS procedures were compared with those who did not. Clinical outcomes such as dose of analgesics, and length of hospital stay were recorded.

RESULTS

During the study period, 128 patients were enrolled. Available demographic characteristics of the 2 groups were compared, and no statistical differences were observed. The rates of shorter temporary ventilator dependence after operations were lower in the rib fixation group (0% vs. 24.7%, P = 0.017). Persistent air leakage more than 5 days after operations were also lower in the rib fixation group (0% vs. 10.4%, P = 0.001). The length of stay in overall hospital stay were longer for patients who received VATS without rib fixation (9.29 ± 2.51 days vs. 12.39 ± 4.65, P = 0.001). Furthermore, the rib fixation group were administered much lower doses of opiates during their hospital stays (52.45 ± 15.67 mg vs. 77.24 ± 50.42 mg, P = 0.001).

CONCLUSION

Adding rib fixation during VATS in the management of retained hemothorax can contribute to shorten whole treatment courses. Rib fixation can also reduce pain, thus reducing dependence on analgesics.

Is observation for traumatic hemothorax safe?

BACKGROUND

Eastern Association for the Surgery of Trauma guidelines suggest tube thoracostomy (TT) be considered for all traumatic hemothoraces. However, previous research has suggested that some traumatic hemothoraces may be observed safely. We sought to (1) determine the safety of selective observation for traumatic hemothorax and (2) identify predictors of failed observation.

METHODS

All patients with traumatic hemothorax from 2000 to 2014 at a Level I trauma center were identified and categorized by size as small (<300 cc) or large (≥300 cc) based on chest computed tomography (CT) scan measurements. Patients with no CT or with TT placement before CT were excluded. Patients were categorized into four intervention groups: (i) early TT (<24 hours after CT), (ii) failed observation (TT ≥24 hours after CT), (iii) successful observation (no TT), and (iv) inevaluable due to early mortality (no TT but died within 7 days). Univariate analyses compared outcomes between groups. Multivariate analyses identified independent predictors of failed observation.

RESULTS

Three hundred forty patients met the inclusion criteria. 156 (46%) patients received early TT. Of the 184 patients that were initially observed, 121 (66%) were successfully observed, 53 (29%) failed observation, and 10 (5%) were inevaluable due to early mortality. Most of the successfully observed hemothoraces were small (119/121, 98%). Four independent predictors of failed observation were identified: older age, fewer ventilation-free days, large hemothorax, concurrent pneumothorax. Patients, who received TT were more likely than non-TT patients to receive tissue plasminogen activator, develop an empyema, have fewer hospital-free days, and are discharged to rehabilitation rather than home. When compared to early TT, failed observation was associated with a higher likelihood of discharge to rehabilitation but no difference in mortality, hospital-free days, or rate of empyema.

CONCLUSION

Initial observation in select patients is safe and may result in better outcomes. The identified predictors of failed observation can help in clinical decision making regarding the need for TT in patients with traumatic hemothorax.

LEVEL OF EVIDENCE

Therapeutic/care management, level IV.

Early Management of Retained Hemothorax in Blunt Head and Chest Trauma

Background

Major blunt chest injury usually leads to the development of retained hemothorax and pneumothorax, and needs further intervention. However, since blunt chest injury may be combined with blunt head injury that typically requires patient observation for 3–4 days, other critical surgical interventions may be delayed. The purpose of this study is to analyze the outcomes of head injury patients who received early, versus delayed thoracic surgeries.

Materials and methods

From May 2005 to February 2012, 61 patients with major blunt injuries to the chest and head were prospectively enrolled. These patients had an intracranial hemorrhage without indications of craniotomy. All the patients received video-assisted thoracoscopic surgery (VATS) due to retained hemothorax or pneumothorax. Patients were divided into two groups according to the time from trauma to operation, this being within 4 days for Group 1 and more than 4 days for Group 2. The clinical outcomes included hospital length of stay (LOS), intensive care unit (ICU) LOS, infection rates, and the time period of ventilator use and chest tube intubation.

Result

All demographics, including age, gender, and trauma severity between the two groups showed no statistical differences. The average time from trauma to operation was 5.8 days. The ventilator usage period, the hospital and ICU length of stay were longer in Group 2 (6.77 vs. 18.55, p = 0.016; 20.63 vs. 35.13, p = 0.003; 8.97 vs. 17.65, p = 0.035). The rates of positive microbial cultures in pleural effusion collected during VATS were higher in Group 2 (6.7 vs. 29.0%, p = 0.043). The Glasgow Coma Scale score for all patients improved when patients were discharged (11.74 vs. 14.10, p < 0.05).

Discussion

In this study, early VATS could be performed safely in brain hemorrhage patients without indication of surgical decompression. The clinical outcomes were much better in patients receiving early intervention within 4 days after trauma.

Management of haemothoraces in blunt thoracic trauma: study protocol for a randomised controlled trial

INTRODUCTION

Haemothorax following blunt thoracic trauma is a common source of morbidity and mortality. The optimal management of moderate to large haemothoraces has yet to be defined. Observational data have suggested that expectant management may be an appropriate strategy in stable patients. This study aims to compare the outcomes of patients with haemothoraces following blunt thoracic trauma treated with either chest drainage or expectant management.

METHODS AND ANALYSIS

This is a single-centre, dual-arm randomised controlled trial. Patients presenting with a moderate to large sized haemothorax following blunt thoracic trauma will be assessed for eligibility. Eligible patients will then undergo an informed consent process followed by randomisation to either (1) chest drainage (tube thoracostomy) or (2) expectant management. These groups will be compared for the rate of additional thoracic interventions, major thoracic complications, length of stay and mortality.

ETHICS AND DISSEMINATION

This study has been approved by the institution's research ethics board and registered with ClinicalTrials.gov. All eligible participants will provide informed consent prior to randomisation. The results of this study may provide guidance in an area where there remains significant variation between clinicians. The results of this study will be published in peer-reviewed journals and presented at national and international conferences.

TRIAL REGISTRATION NUMBER

NCT03050502.

Thoracic Trauma

Management of chest trauma is integral to patient outcomes owing to the vital structures held within the thoracic cavity. Understanding traumatic chest injuries and appropriate management plays a pivotal role in the overall well-being of both blunt and penetrating trauma patients. Whether the injury includes rib fractures, associated pulmonary injuries, or tracheobronchial tree injuries, every facet of management may impact the short- and long-term outcomes, including mortality. This article elucidates the workup and management of the thoracic cage, pulmonary and tracheobronchial injuries.

Use of an evidence-based algorithm for patients with traumatic hemothorax reduces need for additional interventions

BACKGROUND

Concerted management of the traumatic hemothorax is ill-defined. Surgical management of specific hemothoraces may be beneficial. A comprehensive strategy to delineate appropriate patients for additional procedures does not exist. We developed an evidence-based algorithm for hemothorax management. We hypothesize that the use of this algorithm will decrease additional interventions.

METHODS

A pre-/post-study was performed on all patients admitted to our trauma service with traumatic hemothorax from August 2010 to September 2013. An evidence-based management algorithm was initiated for the management of retained hemothoraces. Patients with length of stay (LOS) less than 24 hours or admitted during an implementation phase were excluded. Study data included age, Injury Severity Score, Abbreviated Injury Scale chest, mechanism of injury, ventilator days, intensive care unit (ICU) LOS, total hospital LOS, and interventions required. Our primary outcome was number of patients requiring more than 1 intervention. Secondary outcomes were empyema rate, number of patients requiring specific additional interventions, 28-day ventilator-free days, 28-day ICU-free days, hospital LOS, all-cause 6-month readmission rate. Standard statistical analysis was performed for all data.

RESULTS

Six hundred forty-two patients (326 pre and 316 post) met the study criteria. There were no demographic differences in either group. The number of patients requiring more than 1 intervention was significantly reduced (49 pre vs. 28 post, p = 0.02). Number of patients requiring VATS decreased (27 pre vs. 10 post, p < 0.01). Number of catheters placed by interventional radiology increased (2 pre vs. 10 post, p = 0.02). Intrapleural thrombolytic use, open thoracotomy, empyema, and 6-month readmission rates were unchanged. The "post" group more ventilator-free days (median, 23.9 vs. 22.5, p = 0.04), but ICU and hospital LOS were unchanged.

CONCLUSION

Using an evidence-based hemothorax algorithm reduced the number of patients requiring additional interventions without increasing complication rates. Defined criteria for surgical intervention allows for more appropriate utilization of resources.

LEVEL OF EVIDENCE

Therapeutic study, level IV.

Thoracic radiation-induced pleural effusion and risk factors in patients with lung cancer

The risk factors and potential practice implications of radiation-induced pleural effusion (RIPE) are undefined. This study examined lung cancer patients treated with thoracic radiation therapy (TRT) having follow-up computed tomography (CT) or 18F-fluorodeoxyglucose (FDG) positron emission tomography (PET)/CT. Increased volumes of pleural effusion after TRT without evidence of tumor progression was considered RIPE. Parameters of lung dose-volume histogram including percent volumes irradiated with 5-55 Gy (V5-V55) and mean lung dose (MLD) were analyzed by receiver operating characteristic analysis. Clinical and treatment-related risk factors were detected by univariate and multivariate analyses. 175 out of 806 patients receiving TRT with post-treatment imaging were included. 51 patients (24.9%) developed RIPE; 40 had symptomatic RIPE including chest pain (47.1%), cough (23.5%) and dyspnea (35.3%). Female (OR = 0.380, 95% CI: 0.156-0.926, p = 0.033) and Caucasian race (OR = 3.519, 95% CI: 1.327-9.336, p = 0.011) were significantly associated with lower risk of RIPE. Stage and concurrent chemotherapy had borderline significance (OR = 1.665, p = 0.069 and OR = 2.580, p = 0.080, respectively) for RIPE. Patients with RIPE had significantly higher whole lung V5-V40, V50 and MLD. V5 remained as a significant predictive factor for RIPE and symptomatic RIPE (p = 0.007 and 0.022) after adjusting for race, gender and histology. To include, the incidence of RIPE is notable. Whole lung V5 appeared to be the most significant independent risk factor for symptomatic RIPE.

Computed tomography scoring system for discriminating between parapneumonic effusions eventually drained and those cured only with antibiotics

BACKGROUND AND OBJECTIVE

Due to limited data, we aimed to develop and validate a computed tomography (CT)-based scoring system for identifying those parapneumonic effusions (PPEs) requiring drainage.

METHODS

A retrospective review of all patients with PPE who underwent thoracentesis and a chest CT scan before any attempt to place a tube thoracostomy, if applicable, over an 8-year period was conducted. Eleven chest CT characteristics were compared between 90 patients with complicated PPEs (CPPEs), defined as those which eventually required chest drainage, and 60 with non-complicated effusions (derivation sample). A scoring system was devised with those CT findings identified as independent predictors of CPPE in a logistic regression analysis, and further validated in an independent population of 59 PPE patients.

RESULTS

CT scores predicting CPPE were pleural contrast enhancement (3 points), pleural microbubbles, increased extrapleural fat attenuation and fluid volume ≥400 mL (1 point each). A sum score of ≥4 yielded 84% sensitivity (95% CI: 62-85%), 75% specificity (95% CI: 62-85%), 81% diagnostic accuracy (95% CI: 73-86%), likelihood ratio (LR) positive of 3.4 (95% CI: 2.1-5.4), LR negative of 0.22 (95% CI: 0.13-0.36) and area under the receiver operating characteristic curve (AUC) of 0.829 (95% CI: 0.754-0.904) for labelling CPPE in the derivation set. These results were reproduced in the validation sample. The CT grading scale also exhibited a fair ability to identify patients who needed surgery or would die from the pleural infection (AUC: 0.76, 95% CI: 0.61-0.9).

CONCLUSION

A novel CT scoring system for adults with PPE may allow clinicians to predict the need for chest tube drainage with good accuracy.

A quantitative evaluation of pleural effusion on computed tomography scans using B-spline and local clustering level set

Estimation of the pleural effusion's volume is an important clinical issue. The existing methods cannot assess it accurately when there is large volume of liquid in the pleural cavity and/or the patient has some other disease (e.g. pneumonia). In order to help solve this issue, the objective of this study is to develop and test a novel algorithm using B-spline and local clustering level set method jointly, namely BLL. The BLL algorithm was applied to a dataset involving 27 pleural effusions detected on chest CT examination of 18 adult patients with the presence of free pleural effusion. Study results showed that average volumes of pleural effusion computed using the BLL algorithm and assessed manually by the physicians were 586 ml±339 ml and 604±352 ml, respectively. For the same patient, the volume of the pleural effusion, segmented semi-automatically, was 101.8% ±4.6% of that was segmented manually. Dice similarity was found to be 0.917±0.031. The study demonstrated feasibility of applying the new BLL algorithm to accurately measure the volume of pleural effusion.

Intrapleural alteplase decreases parapneumonic effusion volume in children more than saline irrigation

OBJECTIVE

In this prospective, double-blind, randomized crossover trial, we determined the effect of intrapleural fibrinolysis with alteplase compared to that of normal saline irrigation on the thoracostomy tube output and pleural effusion volume in children with complicated parapneumonic effusion.

METHODS

Twenty seven children, median age 3.5 years, referred to the interventional radiology service for thoracostomy tube drainage of a parapneumonic effusion were studied. Seventeen patients with pleural fluid thickness greater than 2 cm or >20% ipsilateral chest volume after 8 hr of thoracostomy tube drainage entered the treatment arm. They were randomized to receive alteplase 0.1 mg/kg twice a day on days 1 and 3, or on days 2 and 4, with normal saline irrigation on the alternate days. Daily pleural fluid volume measured by low dose chest computed tomography (CT) and thoracostomy tube output was compared between the saline and alteplase groups.

RESULTS

Compared to normal saline irrigation, alteplase irrigation resulted in increased thoracostomy tube drainage and to a greater decline in pleural fluid volume. Earlier alteplase administration resulted in increased fluid mobilization compared to administration later in the hospital course. There were no bleeding complications.

CONCLUSIONS

Intrapleural fibrinolysis with alteplase safely increases pleural drainage and decreases the volume of pleural inflammatory debris compared to intrapleural administration of normal saline. The benefit of intrapleural alteplase on decreasing the volume of pleural inflammatory debris occurs for up to 72 hr with repeated twice daily dosing.

Quantification of interstitial fluid on whole body CT: comparison with whole body autopsy

PURPOSE

Interstitial fluid accumulation can occur in pleural, pericardial, and peritoneal spaces, and subcutaneous tissue planes. The purpose of the study was to assess if whole body CT examination in a postmortem setting could help determine the presence and severity of third space fluid accumulation in the body.

MATERIALS AND METHODS

Our study included 41 human cadavers (mean age 61 years, 25 males and 16 females) who had whole-body postmortem CT prior to autopsy. All bodies were maintained in the morgue in the time interval between death and autopsy. Two radiologists reviewed the whole-body CT examinations independently to grade third space fluid in the pleura, pericardium, peritoneum, and subcutaneous space using a 5-point grading system. Qualitative CT grading for third space fluid was correlated with the amount of fluid found on autopsy and the quantitative CT fluid volume, estimated using a dedicated software program (Volume, Syngo Explorer, Siemens Healthcare).

RESULTS

Moderate and severe peripheral edema was seen in 16/41 and 7/41 cadavers respectively. It is not possible to quantify anasarca at autopsy. Correlation between imaging data for third space fluid and the quantity of fluid found during autopsy was 0.83 for pleural effusion, 0.4 for pericardial effusion and 0.9 for ascites. The degree of anasarca was significantly correlated with the severity of ascites (p < 0.0001) but not with pleural or pericardial effusion. There was strong correlation between volumetric estimation and qualitative grading for anasarca (p < 0.0001) and pleural effusion (p < 0.0001).

CONCLUSION

Postmortem CT can help in accurate detection and quantification of third space fluid accumulation. The quantity of ascitic fluid on postmortem CT can predict the extent of anasarca.

CT volumetric analysis of pleural effusions: a comparison with thoracentesis volumes

RATIONALE AND OBJECTIVES

The primary objective of this study was to compare computed tomography (CT) volumetric analysis of pleural effusions with thoracentesis volumes. The secondary objective of this study was to compare subjective grading of pleural effusion size with thoracentesis volumes.

MATERIALS AND METHODS

This was a retrospective study of 67 patients with free-flowing pleural effusions who underwent therapeutic thoracentesis. CT volumetric analysis was performed on all patients; the CT volumes were compared with the thoracentesis volumes. In addition, the subjective grading of pleural effusion size was compared with the thoracentesis volumes.

RESULTS

The average difference between CT volume and thoracentesis volume was 9.4 mL (1.3%) ± 290 mL (30%); these volumes were not statistically different (P = .79, paired two-tailed Student's t-test). The thoracentesis volume of a "small," "moderate," and "large" pleural effusion, as graded on chest CT, was found to be approximately 410 ± 260 cc, 770 ± 270 mL and 1370 ± 650 mL, respectively; the thoracentesis volume of a "small," "moderate," and "large" pleural effusion, as graded on chest radiograph, was found to be approximately 610 ± 320 mL, 1040 ± 460 mL, and 1530 ± 830 mL, respectively.

CONCLUSIONS

CT volumetric analysis is an accessible tool that can be used to accurately quantify the size of pleural effusions.

To drain or not to drain? Predictors of tube thoracostomy insertion and outcomes associated with drainage of traumatic hemothoraces

INTRODUCTION

Historical data suggests that many traumatic hemothoraces (HTX) can be managed expectantly without tube thoracostomy (TT) drainage. The purpose of this study was to identify predictors of TT, including whether the quantity of pleural blood predicted tube placement, and to evaluate outcomes associated with TT versus expected management (EM) of traumatic HTXs.

PATIENTS AND METHODS

A retrospective cohort study of all trauma patients with HTXs and an Injury Severity Score (ISS) ≥12 managed at a level I trauma centre between April 1, 2005 and December 31, 2012 was completed. Mixed-effects models with a subject-specific random intercept were used to identify independent risk factors for TT. Logistic and log-linear regression were used to compute odds ratios (ORs) for mortality and empyema and percent increases in length of hospital and intensive care unit stay between patients managed with TT versus EM, respectively.

RESULTS

A total of 635 patients with 749 HTXs were included in the study. Overall, 491 (66%) HTXs were drained while 258 (34%) were managed expectantly. Independent predictors of TT placement included concomitant ipsilateral flail chest [OR 3.03; 95% confidence interval (CI) 1.04-8.80; p=0.04] or pneumothorax (OR 6.19; 95% CI 1.79-21.5; p<0.01) and the size of the HTX (OR per 10cc increase 1.12; 95% CI 1.04-1.21; p<0.01). Although the adjusted odds of mortality were not significantly different between groups (OR 3.99; 95% CI 0.87-18.30; p=0.08), TT was associated with a 47.14% (95% CI, 25.57-69.71%; p<0.01) adjusted increase in hospital length of stay. Empyemas (n=29) only occurred among TT patients.

CONCLUSIONS

Expectant management of traumatic HTX was associated with a shorter length of hospital stay, no empyemas, and no increase in mortality. Although EM of smaller HTXs may be safe, these findings must be confirmed by a large multi-centre cohort study and randomized controlled trials before they are used to guide practice.

Derivation and validation of a CT scan scoring system for discriminating malignant from benign pleural effusions

BACKGROUND

Chest CT scanning has become an integral part of the workup for undiagnosed pleural effusions. We aimed to develop a CT scan-based scoring system for differentiating between benign and malignant pleural effusions.

METHODS

A number of chest CT scan abnormalities were compared between 228 patients with benign and 115 with malignant effusions (derivation cohort). A logistic regression analysis was used to identify the independent predictors of malignancy and generate CT scan scores, with more points assigned to those findings associated with higher β-coefficient values. The diagnostic accuracy of the CT scan scoring system was calculated for the derivation cohort and further evaluated in two independent populations (n = 80 and 42, respectively) by two radiologists.

RESULTS

CT scan scores predicting malignancy included any pleural lesion (ie, nodule, mass, or thickening) ≥ 1 cm (5 points); the presence of liver metastases, an abdominal mass, or a lung mass or nodule ≥ 1 cm (3 points each); and the absence of either pleural loculations, pericardial effusions, or cardiomegaly (2 points each). In the first validation cohort, a sum score of ≥ 7 yielded a sensitivity of 88% (95% CI, 73%-95%), specificity of 94% (95% CI, 83%-98%), likelihood ratio positive of 13.8 (95% CI, 4.6-41.5), likelihood ratio negative of 0.13 (95% CI, 0.05-0.33), and area under the receiver operating characteristics curve of 0.919 (95% CI, 0.849-0.990). Moreover, 69% of 42 patients with pathologically unconfirmed malignant effusions from a second independent cohort would have been correctly labeled by the predictive score.

CONCLUSIONS

A simple CT scan-based scoring system can help physicians to separate malignant from benign pleural effusions.

A simple assessment of haemothoraces thickness predicts abundant transfusion: a series of 525 blunt trauma patients

BACKGROUND

The goal of this study was to evaluate the performance of haemothorax quantification to predict an abundant transfusion in blunt thoracic trauma patients.

METHODS

This study included all severe trauma patients admitted into our trauma centre from January 2005 to January 2010, who presented a blunt thoracic trauma (thoracic AIS ≥1) and had a CT scan within the first hour following admission. For each haemothorax, thickness of dominant side and the cumulated thicknesses of both sides (Dominant-t, Cumulated-t), as well as lengths (Dominant-l, Cumulated-l) and the calculated volumes (Dominant-v, Cumulated-v provided by a previously validated formula) were retrospectively measured by CT scan. A multiple logistic regression was performed to define the independent risk factors for an abundant transfusion (≥5 packed red blood cells in the first 24h). Finally, ROC curves have been drawn on an isolated thoracic trauma subgroup to predict abundant transfusion. The more specific cut-offs were extracted from this analysis.

RESULTS

From the 525 blunt thoracic trauma patients (75% males, mean age 38.2 (SD18.7) years, mean ISS 22.5 (SD16.4)), 31% received an abundant transfusion. In multivariable analysis, Cumulated-t was significantly associated with an abundant transfusion (OR 1.3 [95% CI 1.1-1.4], P=0.002). In isolated thoracic trauma subgroup (n=251), the global abilities of different CT measurements to predict abundant transfusion were significantly comparable (AUCs 0.69-0.70). The more specific cut-offs were established at 28mm for Cumulated-t (specificity 92%, positive predictive value 47%) and at 24mm for Dominant-t (specificity 92%; positive predictive value 43%).

CONCLUSION

The haemothorax quantification upon admission may help to predict transfusion needs. Cumulated-t was found independent risk factor for abundant transfusion in a large population of severe trauma patients. Beyond a Cumulated-t of 28mm or a Dominant-t of 24mm, abundant transfusion will be very frequently necessary.

LEVEL OF EVIDENCE

Retrospective review, level III.

Lung in dengue: computed tomography findings

BACKGROUND

Dengue is the most important mosquito-borne viral disease in the world. Dengue virus infection may be asymptomatic or lead to undifferentiated fever, dengue fever with or without warning signs, or severe dengue. Lower respiratory symptoms are unusual and lung-imaging data in patients with dengue are scarce.

METHODOLOGY/PRINCIPAL FINDINGS

To evaluate lung changes associated with dengue infection, we retrospectively analyzed 2,020 confirmed cases of dengue. Twenty-nine of these patients (11 females and 18 males aged 16-90 years) underwent chest computed tomography (CT), which yielded abnormal findings in 17 patients: 16 patients had pleural effusion (the sole finding in six patients) and 11 patients had pulmonary abnormalities. Lung parenchyma involvement ranged from subtle to moderate unilateral and bilateral abnormalities. The most common finding was ground-glass opacity in eight patients, followed by consolidation in six patients. Less common findings were airspace nodules (two patients), interlobular septal thickening (two patients), and peribronchovascular interstitial thickening (one patient). Lung histopathological findings in four fatal cases showed thickening of the alveolar septa, hemorrhage, and interstitial edema.

CONCLUSIONS/SIGNIFICANCE

In this largest series involving the use of chest CT to evaluate lung involvement in patients with dengue, CT findings of lower respiratory tract involvement were uncommon. When abnormalities were present, pleural effusion was the most frequent finding and lung involvement was often mild or moderate and bilateral. Extensive lung abnormalities are infrequent even in severe disease and when present should lead physicians to consider other diagnostic possibilities.

Pleural effusions in patients with Hodgkin lymphoma: clinical predictors and associations with outcome

Pleural effusions are common in Hodgkin lymphoma (HL). However, little is known about their prognostic significance. One hundred and ten patients with HL who presented to the University of Rochester from 1 January 2003 to 12 December 2010 were reviewed. Pleural effusions were evaluated on review of diagnostic-quality computed tomography (CT) scans. Pleural effusions were present in 26/110 patients: 1/7 (14%) stage I, 11/61 (18%) stage II, 3/18 (17%) stage III and 11/24 (46%) stage IV, and 25/91 (27%) patients had mediastinal involvement, 16/38 (42%) patients had extranodal involvement (any) and 5/14 (35%) patients had E lesions (direct extension to extranodal tissue). Unilateral and bilateral pleural effusions were equally prevalent. Survival analysis demonstrated decreased overall survival for patients with pleural effusions of borderline significance for stage I-IV (p = 0.055) but failed to show significance for patients with stage I-III (p = 0.115). Increasing stage, any extranodal involvement and bulky mediastinal disease were each predictive of pleural effusions. The presence of pleural effusion at presentation may be predictive of inferior survival for patients with Hodgkin lymphoma.

Risk factors for post-traumatic pneumonia in patients with retained haemothorax: results of a prospective, observational AAST study

INTRODUCTION

Retained haemothorax (RH) is a problematic sequela of thoracic trauma, reported in up to 20% of patients following chest injury. RH is associated with a higher severity of thoracic trauma and may portend the onset of other serious post-traumatic complications, including pneumonia. The development of pneumonia has previously been reported to be as high as 19.5% in the setting of traumatic RH. The purpose of this study was to identify risk factors for the development of pneumonia as a complication in RH.

METHODS

We utilized the American Association for the Surgery of Trauma Post-Traumatic Retained Haemothorax database. Patients with post-traumatic RH were prospectively enrolled from 2009 to 2011. Inclusion criteria were placement of a thoracostomy tube within 24h of admission for the evacuation of pneumothorax or haemothorax and subsequent chest computed tomography scan chest showing RH. Patients treated with thoracotomy before placement of tube thoracostomy were excluded. For univariate analysis, the Chi-square test with Yates correction was used for comparison of categorical risk factors and the Student's t-test or the Mann-Whitney test for comparison of continuous risk factors. To identify independent risk factors for the development of pneumonia, variables from the univariate analysis significant at p<0.2 were entered into a forward logistic regression model. Adjusted odds ratio and 95% confidence intervals (CI) were derived.

RESULTS

328 patients with post-traumatic RH from 20 United States centres were enrolled. After stepwise regression analysis, ISS>25 (adjusted OR: 7.1; 95% CI: 3.1, 16.4; p<0.001), blunt mechanism of injury (adjusted OR: 3.5; 95% CI: 1.7, 7.2; p=0.001), and failure to administer peri-procedural antibiotics on the initial thoracostomy tube placement (adjusted OR: 2.6; 95% CI: 1.30, 5.4; p=0.01) were found to be independent predictors of the pneumonia in patients with post-traumatic RH.

CONCLUSIONS

To our knowledge, our current study is the largest attempt to identify the independent predictors for pneumonia in this population. Our data show that elevated ISS, blunt thoracic trauma, and failure to administer peri-procedural antibiotics on tube thoracostomy placement are the statistically significant independent risk factors.

The preliminary exploration of 64-slice volume computed tomography in the accurate measurement of pleural effusion

BACKGROUND

Using computed tomography (CT) to rapidly and accurately quantify pleural effusion volume benefits medical and scientific research. However, the precise volume of pleural effusions still involves many challenges and currently does not have a recognized accurate measuring.

PURPOSE

To explore the feasibility of using 64-slice CT volume-rendering technology to accurately measure pleural fluid volume and to then analyze the correlation between the volume of the free pleural effusion and the different diameters of the pleural effusion.

MATERIAL AND METHODS

The 64-slice CT volume-rendering technique was used to measure and analyze three parts. First, the fluid volume of a self-made thoracic model was measured and compared with the actual injected volume. Second, the pleural effusion volume was measured before and after pleural fluid drainage in 25 patients, and the volume reduction was compared with the actual volume of the liquid extract. Finally, the free pleural effusion volume was measured in 26 patients to analyze the correlation between it and the diameter of the effusion, which was then used to calculate the regression equation.

RESULTS

After using the 64-slice CT volume-rendering technique to measure the fluid volume of the self-made thoracic model, the results were compared with the actual injection volume. No significant differences were found, P = 0.836. For the 25 patients with drained pleural effusions, the comparison of the reduction volume with the actual volume of the liquid extract revealed no significant differences, P = 0.989. The following linear regression equation was used to compare the pleural effusion volume (V) (measured by the CT volume-rendering technique) with the pleural effusion greatest depth (d): V = 158.16 × d - 116.01 (r = 0.91, P = 0.000). The following linear regression was used to compare the volume with the product of the pleural effusion diameters (l × h × d): V = 0.56 × (l × h × d) + 39.44 (r = 0.92, P = 0.000).

CONCLUSION

The 64-slice CT volume-rendering technique can accurately measure the volume in pleural effusion patients, and a linear regression equation can be used to estimate the volume of the free pleural effusion.

A new, simple method for estimating pleural effusion size on CT scans

BACKGROUND

There is no standardized system to grade pleural effusion size on CT scans. A validated, systematic grading system would improve communication of findings and may help determine the need for imaging guidance for thoracentesis.

METHODS

CT scans of 34 patients demonstrating a wide range of pleural effusion sizes were measured with a volume segmentation tool and reviewed for qualitative and simple quantitative features related to size. A classification rule was developed using the features that best predicted size and distinguished among small, moderate, and large effusions. Inter-reader agreement for effusion size was assessed on the CT scans for three groups of physicians (radiology residents, pulmonologists, and cardiothoracic radiologists) before and after implementation of the classification rule.

RESULTS

The CT imaging features found to best classify effusions as small, moderate, or large were anteroposterior (AP) quartile and maximum AP depth measured at the midclavicular line. According to the decision rule, first AP-quartile effusions are small, second AP-quartile effusions are moderate, and third or fourth AP-quartile effusions are large. In borderline cases, AP depth is measured with 3-cm and 10-cm thresholds for the upper limit of small and moderate, respectively. Use of the rule improved interobserver agreement from κ = 0.56 to 0.79 for all physicians, 0.59 to 0.73 for radiology residents, 0.54 to 0.76 for pulmonologists, and 0.74 to 0.85 for cardiothoracic radiologists.

CONCLUSIONS

A simple, two-step decision rule for sizing pleural effusions on CT scans improves interobserver agreement from moderate to substantial levels.

Automatic segmentation and measurement of pleural effusions on CT

Pleural effusion is an important biomarker for the diagnosis of many diseases. We develop an automated method to evaluate pleural effusion on CT scans, the measurement of which is prohibitively time consuming when performed manually. The method is based on parietal and visceral pleura extraction, active contour models, region growing, Bezier surface fitting, and deformable surface modeling. Twelve CT scans with three manual segmentations were used to validate the automatic segmentation method. The method was then applied on 91 additional scans for visual assessment. The segmentation method yielded a correlation coefficient of 0.97 and a Dice coefficient of 0.72±0.13 when compared to a professional manual segmentation. The visual assessment estimated 83% cases with negligible or small segmentation errors, 14% with medium errors, and 3% with large errors.

Evaluation of the renal resistive index and pulsatility index in patients with pleural effusion by duplex Doppler ultrasonography

OBJECTIVE

The aim of the study was to evaluate the renal resistive index (RI) and pulsatility index (PI) in patients with pleural effusion (PE).

MATERIALS AND METHODS

We studied the mean renal RI and PI in 50 patients with PE and 30 healthy volunteers by Doppler sonography. We grouped effusion as unilateral and bilateral. Statistical analysis was done by independent t test and correlation coefficient analysis.

RESULTS

The mean RI/PI in healthy volunteers and in PE patients was 0.58/0.93 and 0.72/1.35, respectively. We observed a significantly higher RI and PI in patients when compared with healthy volunteers (all p < 0.001). We found no difference between the renal RI or PI related to unilateral (0.71 or 1.34, respectively) or bilateral effusion (0.74 or 1.55, respectively) (p > 0.05).

CONCLUSION

Pleural effusion might result in increased renal impedance as seen in cirrhosis, which is a rather complicated pathophysiological process, without causing any morphological changes in kidneys.

Management of post-traumatic retained hemothorax: a prospective, observational, multicenter AAST study

BACKGROUND

The natural history and optimal management of retained hemothorax (RH) after chest tube placement is unknown. The intent of our study was to determine practice patterns used and identify independent predictors of the need for thoracotomy.

METHODS

An American Association for the Surgery of Trauma multicenter prospective observational trial was conducted, enrolling patients with placement of chest tube within 24 hours of trauma admission and RH on subsequent computed tomography of the chest. Demographics, interventions, and outcomes were analyzed. Logistic regression analysis was used to identify the independent predictors of successful intervention for each of the management choices chosen and complications.

RESULTS

RH was identified in 328 patients from 20 centers. Video-assisted thoracoscopy (VATS) was the most commonly used initial procedure in 33.5%, but 26.5% required two and 5.4% required three procedures to clear RH or subsequent empyema. Thoracotomy was ultimately required in 20.4%. The strongest independent predictor of successful observation was estimated volume of RH ≤300 cc (odds ratio [OR], 3.7 [2.0-7.0]; p < 0.001). Independent predictors of successful VATS as definitive treatment were absence of an associated diaphragm injury (OR, 4.7 [1.6-13.7]; p = 0.005), use of periprocedural antibiotics for thoracostomy placement (OR, 3.3 [1.2-9.0]; p = 0.023), and volume of RH ≤900 cc (OR, 3.9 [1.4-13.2]; p = 0.03). No relationship between timing of VATS and success rate was identified. Independent predictors of the need for thoracotomy included diaphragm injury (OR, 4.9 [2.4-9.9]; p < 0.001), RH >900 cc (OR, 3.2 [1.4-7.5]; p = 0.007), and failure to give periprocedural antibiotics for initial chest tube placement (OR 2.3 [1.2-4.6]; p = 0.015). The overall empyema and pneumonia rates for RH patients were 26.8% and 19.5%, respectively.

CONCLUSION

RH in trauma is associated with high rates of empyema and pneumonia. VATS can be performed with high success rates, although optimal timing is unknown. Approximately, 25% of patients require at least two procedures to effectively clear RH or subsequent pleural space infections and 20.4% require thoracotomy.

Thoracic metastasis in advanced ovarian cancer: comparison between computed tomography and video-assisted thoracic surgery

OBJECTIVE

To determine which computed tomography (CT) imaging features predict pleural malignancy in patients with advanced epithelial ovarian carcinoma (EOC) using video-assisted thoracic surgery (VATS), pathology, and cytology findings as the reference standard.

METHODS

This retrospective study included 44 patients with International Federation of Obstetrics and Gynecology (FIGO) stage III or IV primary or recurrent EOC who had chest CT ≤30 days before VATS. Two radiologists independently reviewed the CT studies and recorded the presence and size of pleural effusions and of ascites; pleural nodules, thickening, enhancement, subdiaphragmatic tumour deposits and supradiaphragmatic, mediastinal, hilar, and retroperitoneal adenopathy; and peritoneal seeding. VATS, pathology, and cytology findings constituted the reference standard.

RESULTS

In 26/44 (59%) patients, pleural biopsies were malignant. Only the size of left-sided pleural effusion (reader 1: rho=-0.39, p=0.01; reader 2: rho=-0.37, p=0.01) and presence of ascites (reader 1: rho=-0.33, p=0.03; reader 2: rho=-0.35, p=0.03) were significantly associated with solid pleural metastasis. Pleural fluid cytology was malignant in 26/35 (74%) patients. Only the presence (p=0.03 for both readers) and size (reader 1: rho=0.34, p=0.04; reader 2: rho=0.33, p=0.06) of right-sided pleural effusion were associated with malignant pleural effusion. Interobserver agreement was substantial (kappa=0.78) for effusion size and moderate (kappa=0.46) for presence of solid pleural disease. No other CT features were associated with malignancy at biopsy or cytology.

CONCLUSION

In patients with advanced EOC, ascites and left-sided pleural effusion size were associated with solid pleural metastasis, while the presence and size of right-sided effusion were associated with malignant pleural effusion. No other CT features evaluated were associated with pleural malignancy.

Pleural effusion detected at CT prior to primary cytoreduction for stage III or IV ovarian carcinoma: effect on survival

PURPOSE

To determine the prognostic importance of pleural effusions on preoperative computed tomographic (CT) images in patients with advanced epithelial ovarian cancer.

MATERIALS AND METHODS

The institutional review board waived informed consent for this HIPAA-compliant study of 203 patients with International Federation of Obstetrics and Gynecology stage III (n = 172) or IV (n = 31) epithelial ovarian cancer who underwent CT before primary cytoreductive surgery between 1997 and 2004 (mean age, 61 years; range, 37-96 years). Two radiologists retrospectively evaluated chest and/or abdominal CT images for pleural malignancy and the presence, size, and laterality of pleural effusions. To evaluate survival, Kaplan-Meier methods were used, with log-rank P values for comparisons. Multivariate analyses were conducted by using Cox proportional hazards regression. κ Statistics were calculated for interreader agreement.

RESULTS

Median survival was 50 months (95% confidence interval [CI]: 45, 55 months) for patients with stage III disease and 41 months (95% CI: 27, 58 months) for patients with stage IV disease. Readers 1 and 2 found pleural effusions in 40 and 41 stage III and 20 and 21 stage IV patients, respectively. At multivariate analysis, after controlling for stage, age at surgery, preoperative serum CA-125 level, debulking status, and ascites, moderate-to-large pleural effusion on CT images was significantly associated with worse overall survival (reader 1: hazard ratio = 2.27 [95% CI: 1.31, 3.92], P < .01; reader 2: hazard ratio = 2.25 [95% CI: 1.26, 4.01], P = .02). Preoperative CA-125 level, debulking status, and ascites were also significant survival predictors (P ≤ .03 for all for both readers). Readers agreed substantially in distinguishing small from moderate-to-large effusions (κ = 0.764).

CONCLUSION

Moderate-to-large pleural effusion on preoperative CT images in patients with stage III or IV epithelial ovarian cancer was independently associated with poorer overall survival after controlling for age, preoperative CA-125 level, surgical stage, ascites, and cytoreductive status.

Semiautomated segmentation of pleural effusions in MDCT datasets

RATIONALE AND OBJECTIVES

To develop and evaluate a novel algorithm for semiautomated segmentation and volumetry of pleural effusions in multidetector computed tomography (MDCT) datasets.

MATERIALS AND METHODS

A seven-step algorithm for semiautomated segmentation of pleural effusions in MDCT datasets was developed, mainly using algorithms from the ITK image processing library. Semiautomated segmentation of pleural effusions was performed in 40 MDCT datasets of the chest (males = 22, females = 18, mean age: 56.7 +/- 19.3 years). The accuracy of the semiautomated segmentation as compared with a manual segmentation approach was quantified based on the differences of the segmented volumes, the degree of over-/undersegmentation, and the Hausdorff distance. The time needed for the semiautomated and the manual segmentation process were recorded and compared.

RESULTS

The mean volume of the pleural effusions was 557.30 mL (+/- 477.27 mL) for the semiautomated and 553.19 (+/- 473.49 mL) for the manual segmentation. The difference was not statistically significant (Student t-test, P = .133). Regression analysis confirmed a strong relationship between the semiautomated algorithm and the gold standard (r(2) = 0.998). Mean overlap of the segmented areas was 79% (+/- 9.3%) over all datasets with moderate oversegmentation (22% +/- 9.3%) and undersegmentation (21% +/- 9.7%). The mean Hausdorff distance was 17.2 mm (+/- 8.35 mm). The mean duration of the semiautomated segmentation process with user interaction was 8.4 minutes (+/- 2.6 minutes) as compared to 32.9 minutes (+/- 17.4 minutes) for manual segmentation.

CONCLUSION

The semiautomated algorithm for segmentation and volumetry of pleural effusions in MDCT datasets shows a high diagnostic accuracy when compared with manual segmentation.

Differentiation of pleural effusions from parenchymal opacities: accuracy of bedside chest radiography

OBJECTIVE

The purpose of this study was to determine, with CT as the reference standard, the ability of radiologists to detect pleural effusions on bedside chest radiographs.

MATERIALS AND METHODS

Images of 200 hemithoraces in 100 ICU patients undergoing chest radiography and CT within 24 hours were reviewed. Four readers with varying levels of experience reviewed the chest radiographs and predicted the likelihood of the presence of an effusion or parenchymal opacity on independent 5-point scales. The results were compared with the CT findings.

RESULTS

All readers regardless of experience had similar accuracy in detecting pleural effusions. Among 117 pleural effusions, 66% were detected on chest radiographs (53%, 71%, and 92% of small, moderate, and large effusions) with 89% specificity. Similarly, 65% of all parenchymal opacities were detected on chest radiographs, also with 89% specificity. Most (93%) of the misdiagnosed pulmonary opacities were simply not seen. Meniscus, apical cap, lateral band, and subpulmonic opacity were highly specific findings but had low individual sensitivity for effusions. The finding of homogeneous opacity, including both layering and gradient opacities, was the most sensitive sign of effusion. Atelectasis can occasionally mimic the pleural veil sign of effusion, accounting for most false-positive findings.

CONCLUSION

Radiologists interpreting bedside chest radiographs of ICU patients detect large pleural effusions 92% of the time and can exclude large effusions with high confidence. However, small and medium effusions often are misdiagnosed as parenchymal opacities (45%) or are not seen (55%). Pulmonary opacities often are missed (34%) but are rarely misdiagnosed as pleural effusions (7%).

Multiplane ultrasound approach to quantify pleural effusion at the bedside

OBJECTIVE

To assess the accuracy of a multiplane ultrasound approach to measure pleural effusion volume (PEV), considering pleural effusion (PE) extension along the cephalocaudal axis and PE area.

METHODS

Prospective study performed on 58 critically ill patients with 102 PEs. Thoracic drainage was performed in 46 patients (59 PEs) and lung computed tomography (CT) in 24 patients (43 PEs). PE was assessed using bedside lung ultrasound. Adjacent paravertebral intercostal spaces were examined, and ultrasound PEV was calculated by multiplying the paravertebral PE length by its area, measured at half the distance between the apical and caudal limits of the PE.

RESULTS

Ultrasound PEV was compared to either the volume of the drained PE (59 PE) or PEV assessed on lung CT (43 PE). In patients with lung CT, the accuracy of this new method was compared to the accuracy of previous methods proposed for PEV measurement. Ultrasound PEV was tightly correlated with drained PEV (r = 0.84, p < 0.001) and with CT PEV (r = 0.90, p < 0.001). The mean biases between ultrasound and actual volumes of PE were -33 ml when compared to drainage (limits of agreement -292 to +227 ml) and -53 ml when compared to CT (limits of agreement -303 to +198 ml). This new method was more accurate than previous methods to measure PEV.

CONCLUSION

Using a multiplane approach increases the accuracy of lung ultrasound to measure the volume of large to small pleural effusions in critically ill patients.

COMPUTER AIDED EVALUATION OF PLEURAL EFFUSION USING CHEST CT IMAGES

A pleural effusion is a condition where there is a buildup of abnormal fluid within the pleural space. This paper presents an automated method to evaluate the severity of pleural effusion using regular chest CT images. First the lungs are segmented using region growing, mathematical morphology and anatomical knowledge. Then the visceral and parietal layers of the pleura are extracted based on anatomical landmarks, curve fitting and active contour models. Finally, the pleural space is segmented and the pleural effusion is quantified. Our method was tested on 15 chest CT studies. The automated segmentation is validated against manual tracing and radiologist's qualitative grading. The Pearson correlation between computer evaluation and radiologist's grading is 0.956 (P=10(-7)). The Dice coefficient between the automated and manual segmentation is 0.74±0.07, which is comparable to the variation between two different manual tracings.

Transoesophageal echocardiography for the detection and quantification of pleural fluid in cardiac surgical patients

BACKGROUND

Transoesophageal echocardiography (TOE) can image pleural fluid. Left pleural collections may be easier to detect than right, as the thoracic aorta serves as an acoustic window. Attempts to quantify pleural fluid using TOE are restricted to a case report in which volume was predicted by multiplying maximal cross-sectional area (CSA(max)) by axial length (AL). A computed tomography (CT) derived formula for quantifying pleural effusions is maximal effusion depth squared (d2) multiplied by maximal effusion length.

METHODS

Eight patients were studied before chest closure following coronary bypass surgery. Fifty millilitre saline aliquots were instilled into the pleural space until detected by TOE. Saline was then instilled up to the next 200 ml increment and further 200 ml aliquots added until it spilled from the pleural space. CSA(max), d and AL were measured for each stage and used to calculate pleural fluid volume.

RESULTS

Median detection volume (range) was 125 ml (50-200) on the left and 225 ml (150-300) on the right (P = 0.016). Volume calculated by CSA(max) x AL correlated strongly with actual volume (r2 = 0.93 left and 0.92 right) as did volume calculated by d2 x AL (r2 = 0.86 left and 0.89 right). Mean difference between volume calculated by CSA(max) x AL and actual volume was - 51 ml on the left and 45 ml on the right vs - 253 ml on the left and - 212 ml on the right for volume calculated by d2 x AL.

CONCLUSIONS

TOE detects small volumes of pleural fluid on both sides of the chest. CSA(max) x AL provides a reasonably accurate measure of pleural fluid volume.

Analysis of pleural effusions in acute pulmonary embolism: Radiological and pleural fluid data from 230 patients

BACKGROUND AND OBJECTIVE

The aims of this study were to describe the frequency and radiographical characteristics of pleural effusions in a large population of patients with acute pulmonary embolism (PE) and characterize the pleural fluid biochemistry in those patients who underwent diagnostic thoracentesis.

METHODS

This was a retrospective observational single-centre study. A total of 230 consecutive patients with a diagnosis of PE over a 9-year period were enrolled. Spiral CT pulmonary angiography (52%) and high-probability ventilation and perfusion scans (42%) were used as the main reference methods.

RESULTS

Pleural effusions were observed in 32% and 47% of patients by CXR and CT, respectively. Typically, pleural effusions were small (90% occupied less than one third of the hemithorax) and unilateral (85%), but occasionally they reached more than a half of the hemithorax. On CT, 21% of pleural effusions showed loculation. In patients with loculated pleural fluid the diagnosis of PE had been delayed for a mean of 12.2 days after symptoms developed. The presence of pleural fluid was not related to infarction. Twenty-six of 93 (28%) patients with effusions on imaging underwent thoracentesis. All the fluids met Light's criteria for exudate, 58% contained erythrocyte counts >10,000/microL and 46% showed neutrophilic predominance.

CONCLUSIONS

Small pleural effusions, mostly unsuitable for diagnostic thoracentesis, were present in about one third of patients with PE. All the pleural effusions due to PE were exudates. If PE diagnosis was delayed the pleural effusion tended to become loculated.

Incidence and management of occult hemothoraces

BACKGROUND

Little is known about the incidence of and associated management outcomes of occult hemothorax in blunt trauma patients. The increased use of computed thoracic tomography for the evaluation of the multiply injured blunt trauma patient has led to an increase in the identification of these hemothoraces and management dilemmas.

METHODS

A retrospective review of blunt trauma patients with occult hemothoraces was performed. Patients were divided into 2 groups: chest tube versus no chest tube. Outcomes and complications for the 2 groups were defined. Data included demographics, Injury Severity Score, length of stay, need for mechanical ventilation and thoracic consult, pneumonia, and empyema. The size of the occult hemothorax was measured on the computed thoracic tomography.

RESULTS

Eighty-eight patients (21.4%) had a total of 107 occult hemothoraces. Patients in the chest tube group were more likely to have a higher Injury Severity Score and an associated occult pneumothorax and to have smaller hemothoraces.

CONCLUSIONS

Occult pneumothoraces occur in a significant proportion of the multiply injured blunt trauma population. Small, isolated, occult hemothoraces can be managed safely in the stable patient.