Mediastinal Edema Research Articles

MRI of odontogenic maxillofacial infections: diagnostic accuracy and reliability

ObjectivesTo determine the diagnostic accuracy of emergency magnetic resonance imaging (MRI) in odontogenic maxillofacial infections, the clinical and surgical significance of MRI findings, and whether MRI can identify the tooth responsible for the infection.MethodsA retrospective cohort study reviewed 106 emergency neck MRI scans of patients with neck infections of odontogenic origin. The diagnostic accuracy of MRI in identifying abscesses was studied relative to surgical findings. Correlations were analyzed between various MRI findings and clinical results and outcomes, such as the surgical approach (intraoral vs. extraoral). The ability of MRI findings to predict the causative tooth was assessed in a blinded multi-reader setting.ResultsOf the 106 patients with odontogenic infections, 77 (73%) had one or more abscesses. Imaging showed a sensitivity, specificity, and accuracy of 0.95, 0.84, and 0.92, respectively, for MRI diagnosis of an odontogenic abscess. Among the imaging findings, mediastinal edema was the strongest predictor of extraoral surgery. MRI showed bone marrow edema in the majority of patients, and multi-reader assessment showed good reliability. MRI was also able to predict the causative tooth accurately.ConclusionsEmergency neck MRI can accurately detect odontogenic abscesses and reliably point to the causative tooth. These results can increase the utility and reliance on emergency MRI in clinical decision-making.

When Should the Sternum Be Closed After Aortic Surgery?

Introduction: There are many factors affecting postoperative morbidity and mortality in patients managed with delayed sternal closure (DSC) after aortic surgery. This study aimed to examine the postoperative management of patients after DSC and the factors affecting morbidity and mortality. Patients and Methods: Among 2151 patients who underwent ascending aorta and/or aortic valve surgery between January 2012 and December 2020, 64 patients managed with DSC were included in the study. The records of the patients were obtained from the hospital archive/hospital electronic database. Postoperative day 30 was determined as early mortality. Results: Uncontrollable bleeding 34.4% (n= 22), LCOS (Low Cardiac Output Syndrome) 31.4% (n= 20) and mediastinal edema 28.1% (n= 18)were the main causes for DSC. In the remaining patients (6.3%, n= 4), DSC was preferred for other non-specific reasons such as uncontrollable arrhythmia. Forty-five patients’ chests (70.3%) were closed in the postoperative period, and 19 patients (29.7%) could not be closed due to death (p< 0.001). Early mortality was observed in 27 patients (42.2%), and sepsis was observed in 10 patients (15.6%). Deep sternal wound infection (DSWI) was present in 4.7% of the patients and the rate of sepsis was higher in this patient group (66.7%-13.1%, p< 0.05). There was no statistically significant difference in the probability of sepsis in the culture-positive patient group (p> 0.05). However, the closure time was longer in patients with a previous operation history, postoperative acute renal failure, surgical site infection, and postoperative bleeding revision/surgical revision (p< 0.05). Conclusion: DSC can be preferred as a life-saving method for various reasons such as bleeding diathesis, mediastinal edema, and malignant arrhythmia after open-heart surgery. Accurate timing and close follow-up are important for sternal closure. In these patients, a multidisciplinary approach is required in the postoperative period.

P8‐130: Diffuse mediastinal edema caused by thoracic lymphoma; a rare cause for superior vena cava narrowing

P8‐130: Diffuse mediastinal edema caused by thoracic lymphoma; a rare cause for superior vena cava narrowing

Clinical and prognostic significance of emergency MRI findings in neck infections

ObjectivesDue to its superior soft-tissue contrast and ability to delineate abscesses, MRI has high diagnostic accuracy in neck infections. Whether MRI findings can predict the clinical course in these patients is unknown. The purpose of this study was to determine the clinical and prognostic significance of various MRI findings in emergency patients with acute neck infections.Materials and methodsWe retrospectively reviewed the 3-T MRI findings of 371 patients with acute neck infections from a 5-year period in a single tertiary emergency radiology department. We correlated various MRI findings, including retropharyngeal (RPE) and mediastinal edema (ME) and abscess diameter, to clinical findings and outcomes, such as the need for intensive care unit (ICU) treatment and length of hospital stay (LOS).ResultsA total of 201 out of 371 patients (54%) with neck infections showed evidence of RPE, and 81 out of 314 patients (26%) had ME. Both RPE (OR = 9.5, p < 0.001) and ME (OR = 5.3, p < 0.001) were more prevalent among the patients who required ICU treatment than among those who did not. In a multivariate analysis, C-reactive protein (CRP) levels, RPE, and maximal abscess diameter were independent predictors of the need for ICU treatment, and CRP, ME, and maximal abscess diameter were independent predictors of LOS.ConclusionIn patients with an acute neck infection that requires emergency imaging, RPE, ME, and abscess diameter, as shown by MRI, are significant predictors of a more severe illness.Key Points• Two hundred one out of 371 patients (54%) with neck infection showed evidence of retropharyngeal edema (RPE), and 81 out of 314 patients (26%) had mediastinal edema (ME).• Maximal abscess diameter, RPE, and C-reactive protein (CRP) were independent predictors of the need for intensive care unit (ICU) treatment, and maximal abscess diameter, ME, and CRP were independent predictors of length of hospital stay.• Prognostic significance of MRI findings was evident also while controlling for CRP values.

Pre-procedural proton pump inhibition is associated with fewer peri-oesophageal lesions after cryoballoon pulmonary vein isolation

Pulmonary vein isolation (PVI) using cryoenergy is safe and efficient for treatment of atrial fibrillation (AF). Pre-existing upper gastrointestinal (GI) pathologies have been shown to increase the risk for AF. Therefore, this study aimed at assessing incidental pathologies of the upper GI tract in patients scheduled for PVI and to analyse the impact of patients’ characteristics on PVI safety outcome. In 71 AF patients, who participated in the MADE-PVI trial, oesophagogastroduodenoscopy and endosonography were prospectively performed directly before and the day after PVI to assess pre-existing upper GI pathologies and post-interventional occurrence of PVI-associated lesions. Subgroup analysis of the MADE-PVI trial identified clinically relevant incidental findings in 53 patients (74.6%) with age > 50 years being a significant risk factor. Pre-existing reflux oesophagitis increased risk for PVI-associated mediastinal oedema, while patients already treated with proton pump inhibitors (PPI) had significantly fewer mediastinal oedema. Our results suggest that AF patients with pre-existing reflux oesophagitis are at higher risk for PVI-associated mediastinal lesions, which is decreased in patients with constant PPI-treatment prior to PVI. Since PVI-associated mediastinal lesions are regarded as surrogate parameter for an increased risk of the fatal complication of an oesophago-atrial fistula, our findings hint at a beneficial effect of pre-interventional prophylactic PPI-treatment to reduce risk for PVI-associated complications.German Clinical Trials Register (DRKS00016006; date of registration: 17/12/2018).

Serial MRI Findings After Endoscopic Removal of Button Battery From the Esophagus.

OBJECTIVE. The purpose of this study was to evaluate findings at serial MRI after endoscopic removal of a button battery from the esophagus in a series of pediatric patients. MATERIALS AND METHODS. Serial MRI examinations after removal of a button battery from the esophagus were reviewed retrospectively for the presence of mediastinal edema; imaging characteristics of the aorta and arteries; imaging characteristics of the trachea; and imaging characteristics of the esophageal wall at the level of injury. RESULTS. A total of 48 MRI examinations were performed on 19 patients, 89% (17/19) in the first 48 hours after battery removal. Serial MRI was performed for 84% (16/19) of patients. Initial MRI showed extensive mediastinal edema in all 17 patients who underwent MRI in the first 48 hours. Edema directly abutted major arteries in all 17 patients and abutted the airway in all 10 patients with proximal esophageal injury. Arterial vascular changes were seen in 30% (3/10) of patients with proximal esophageal injury and 57% (4/7) of patients with mid or distalesophageal injury. Airway changes were seen in 80% (8/10) of patients with proximal esophageal injury. Serial MRI showed improvement of airway changes in all patients and improvement in vessel wall changes in all but one (25%, 1/4) of the patients who had mid or distal esophageal injury. Four patients (21% [4/19]) had contained esophageal leak on esophagrams. No patients in our series developed a tracheoesophageal or vascular-enteric fistula. CONCLUSION. Our case series provides important information on natural history of MRI findings in children after endoscopic removal of a button battery from the esophagus. Further studies are needed to determine the imaging findings most sensitive and specific for severe complications, such as tracheoesophageal fistula and vascular-enteric fistula.

P342Time-to-isolation-guided cryoballoon pulmonary vein isolation reduces esophageal and mediastinal alterations detected by endoscopic ultrasound

Abstract Background Pulmonary vein isolation (PVI) is recommended for treatment of symptomatic atrial fibrillation. Cryoballoon ablation is an emerging safe and efficient technique for achieving PVI. Nevertheless, structural alterations of the mediastinum and/or the oesophagus, which seem to be associated with an increased risk of the lethal complication of an atrio-oesophageal fistula, have been described. Purpose MADE-PVI (Mediastino-oesophageal Alterations Detected by Endosonography after PVI) aimed at evaluating safety of cryoballoon PVI in relation to two different freeze protocols. As a time-to-isolation (TTI)-guided protocol has been reported to be as effective as a conventional “two freeze protocol”, we hypothesized that a TTI-guided protocol causes less peri-atrial and -oesophageal lesions. Methods 70 consecutive patients were scheduled for de novo cryoballoon (2nd generation) PVI employing either a conventional freeze protocol (Group A: n=35: 2x180s per vein) or a TTI-guided approach (Group B: n=35; freeze time: TTI+120s per vein or 1x180s in case TTI could not be measured). Structural oesophageal and mediastinal alterations (e.g. ulceration, oedema) were assessed by endoscopy and endosonography blinded prior and post ablation. Results Irrespective of used freeze protocol, ablation significantly increased atrio-oesophageal distances, including distance to left and right inferior pulmonary vein ostia as well as to the posterior wall of the left atrium (all p&lt;0.001). In general, postinterventional mediastinal oedematous alterations were detected in 47 patients (70%) with a mean size of 14mm (± 0.9 mm), while only 10 patients (15%) revealed a large mediastinal oedema &gt;20mm. Oesophageal thermal lesions occurred in 3 patients (4%) including 1 deep ulceration, which coincided with a large mediastinal oedema. The two freeze protocols had a distinct impact on mediastinal lesions as mean size of oedematous alterations and occurrence of large mediastinal oedema were significantly increased in Group A vs. Group B (17 mm vs. 11 mm, p&lt;0.001; 26% vs. 6%, p=0.029). Furthermore, every oesophageal lesion was detected in patients in group A. Nonetheless, no major complication occurred in either group. Conclusions The present prospective study clearly demonstrates a significant impact of freeze protocol on post-interventional mediastino-oesophageal alterations. A TTI-guided protocol employing 2nd generation cryoballoon reduces mediastino-oesophageal lesions and may reduce complications. Acknowledgement/Funding This study was supported by Medtronic by an unrestricted grant (A 1351459).

EComment. Post-pneumonectomy empyema with bronchopleural fistula

In this article by Andreetti and colleagues [1], the authors described a modification in the implantation of a tracheobronchial stent to exclude a bronchopleural fistula (PBF) by anchoring it to the tracheal mucosal surface using titanium helical fasteners. The conical-shaped, fully-covered and self-expandable stent (Tracheobronxane Silmet, Novatech SA, France) was successfully used in six patients with post-pneumonectomy BPF. Early identification of the BPF and urgent (within few hours of fistula occurrence) endoscopic implantation and anchoring of the Silmet stent ensured excellent results in all patients without distal migration of the stent. What is remarkable in their report is that none of their patients presented with empyema. We would like to ask the authors if they are disposed to implanting the Silmet stent in patients with post-pneumonectomy empyema? Traditionally in the case of post-pneumonectomy empyema, the BPF must be debrided and the bronchial stump closed and reinforced by an intrathoracic transposition of omentum or muscle flaps [2]. However, isolation of the hilar element and identification of the fistula could be difficult due to mediastinal edema and fibrosis. In the latter case, surgical management consists of an open window thoracotomy and involves daily changes of the intracavitary wound dressings over a long period of time. Negative pressure wound therapy (NPWT) such as the vacuum assisted closure (VAC) therapy device (KCI Inc, San Antonio, TX) has been adopted as an alternative method to classic wound dressings, owing to the accelerated wound healing process [3]. VAC promotes healing through the enhancement of granulation tissue formation, the removal of exudates and oedema, increased tissue perfusion and oxygenation, and wound volume reduction [4]. One major drawback in the application of VAC therapy in the thoracic cavity is the presence of air leaks. To ensure adequate functioning of the VAC system placed inside the chest, the deployment of the Silmet stent in case of a large fistula is an appropriate technique to stop air leaks. Passera et al. [5] recently published a case report concerning a patient with a large bronchopleural fistula and empyema. The surgical strategy consisted of an open window thoracostomy, surgical debridement of the bronchial stump and the deployment of an Amplatzer septal occluder device (AGA Medical Corp, Plymouth, MN) to close the BPF. Thereafter, the thoracostomy rapidly and spontaneously closed with VAC therapy. The combination of endoscopic occlusion of the PBF in the setting of post-pneumonectomy empyema (by using the Silmet stent plus anchoring system or Amplatzer septal occluder device) and application of VAC therapy through the open window thoracotomy seems not only to be safe and effective but also appears to accelerate the healing process and reduce the hospital stay. Future studies with larger numbers of patients will be required to validate the efficacy of the procedure and to draw definitive conclusions. Conflict of Interest: None declared

Outcomes of delayed sternal closure after complex aortic surgery☆

Open chest management during complex proximal aortic surgery may sometimes be necessary. Infectious complications such as mediastinitis and late aortic graft infection remain a concern. The objective of this study was to report our experience with open chest management and delayed sternal closure after complex proximal aortic surgery. Between 1991 and 2007, 12 patients (1.2%, 12/1011) required open chest management and delayed sternal closure. Eight patients were men (67%), with a mean age of 56 years (range 28-83 years). Four cases involved redo-median sternotomy (33%) and seven cases (58%) involved acute dissection. All procedures were performed using total cardiopulmonary bypass with profound hypothermic circulatory arrest. Reasons for open chest management included hemodynamic instability, mediastinal edema, bleeding, and respiratory compromise. In-hospital mortality was 16.7% (2/12). Delayed sternal closure was achieved in 92% of patients (11/12). Mean time to closure was 3 days (range 1-9 days). Five patients (42%) required one or more mediastinal explorations prior to final closure. Mean length of stay was 51 days (range 1-186 days). Significant predictors of open chest management were pump time (p<0.0001) and intra-operative blood transfusions (p<0.002). Mean follow-up was 60 months (range 8-106 months). No patients developed mediastinitis or aortic graft infection during postoperative follow-up. Open chest management with delayed sternal closure after complex aortic repairs may be performed with acceptable mortality. Open chest management does not appear to increase the risk of infectious complications (mediastinitis or graft infections) during complex proximal aortic replacement.

Pathology of Inhalational Anthrax Infection in the African Green Monkey

There is a critical need for an alternative nonhuman primate model for inhalational anthrax infection because of the increasingly limited supply and cost of the current model. This report describes the pathology in 12 African green monkeys (AGMs) that succumbed to inhalational anthrax after exposure to a low dose (presented dose 200-2 x 10(4)colony-forming units [cfu]) or a high dose (presented dose 2 x 10(4)-1 x 10(7) cfu) of Bacillus anthracis (Ames strain) spores. Frequent gross lesions noted in the AGM were hemorrhage and edema in the lung, mediastinum, and mediastinal lymph nodes; pleural and pericardial effusions; meningitis; and gastrointestinal congestion and hemorrhage. Histopathologic findings included necrohemorrhagic lymphadenitis of mediastinal, axillary, inguinal, and mesenteric lymph nodes; mediastinal edema; necrotizing splenitis; meningitis; and congestion, hemorrhage, and edema of the lung, mesentery, mesenteric lymph nodes, gastrointestinal tract, and gonads. Pathologic changes in AGMs were remarkably similar to what has been reported in rhesus macaques and humans that succumbed to inhalational anthrax; thus, AGMs could serve as useful models for inhalation anthrax studies.

Four faces of a parapneumonic effusion: Pathophysiology and varied radiographic presentations

We report a patient methicillin-resistant Staphylococcus aureus pneumonia who developed fluid collections in three spaces in the thorax, the pleural space, the pericardial space, and a pre-existing bulla, in addition to mediastinal oedema. We discuss the universal pathogenesis for the development of these fluid collections and the explanation for the most common presentation being a parapneumonic effusion.

Mediastinal compression secondary to supraglottitis: a case report

Potential fascial spaces of the neck communicate inferiorly with the mediastinum and thus provide a route for spread of infections. It is very uncommon for supraglottitis to spread to one of these spaces. In this rare case, this infection not only involved the parapharyngeal space but also followed the anatomic path down to the mediastinum. The resulting mediastinal edema increased the intrathoracic pressure and thus upset the hemodynamic. Despite being in critical condition due to pulmonary edema and hypotension, the patient recovered without the use of aggressive surgical measures recommended for such cases.

Invited commentary

Invited commentary

Mediastinitis following median sternotomy: CT findings.

To evaluate the usefulness of computed tomography (CT) in the diagnosis of mediastinitis following median sternotomy. Fifty patients aged 6 weeks to 80 years (31 male, 19 female) who underwent CT for clinically suspected mediastinitis following median sternotomy were retrospectively identified. CT scans were evaluated for primary findings (localized mediastinal fluid, pneumomediastinum, or both) versus secondary or other findings (mediastinal edema, adenopathy, pleural effusion, or a sternal or lung abnormality). Patients were divided into three groups on the basis of the CT findings and final clinical diagnosis: those with primary CT signs and a final diagnosis of mediastinitis, those with primary CT signs of mediastinitis and a different final diagnosis, and those with neither primary CT findings nor a final diagnosis of mediastinitis. All patients with clinical mediastinitis had primary CT findings. These patients under went CT an average of 24 days after surgery. Patients with primary CT findings and a final clinical diagnosis of something other than mediastinitis underwent CT an average of 9 days following following surgery. Through postoperative day 14, CT had a sensitivity of 100% for clinical mediastinitis but a specificity of 33%; after postoperative day 14, the sensitivity was 100% and the specificity was 100%. Primary CT findings are not specific for mediastinitis through postoperative day 14; after day 14, they are highly indicative of mediastinitis.

Thoracic manifestations of Behçet syndrome: radiographic and CT findings in nine patients.

To evaluate the radiographic and computed tomographic (CT) findings of patients with thoracic Behçet syndrome. Chest radiographs and CT scans of nine patients with thoracic Behçet syndrome were retrospectively reviewed. Findings were compared. Radiographs of the nine patients showed mediastinal widening in five (56%), air-space consolidation in five (56%), and lung mass in three (33%). CT scans of the nine patients showed that mediastinal widening was due to thrombosis in four (44%) or narrowing of the superior vena cava in one [11%], which caused mediastinal edema; that air-space consolidation (seen on both radiographs and CT scans) was due to pulmonary hemorrhage or infarction in five (56%); and that lung mass was due to aneurysm of the right or left pulmonary artery in three (33%). In addition, CT scans showed hyperinflation in one patient. Chest radiographic findings of thoracic Behçet syndrome are variable and nonspecific. CT can be helpful in the assessment of the syndrome by showing thrombosis of the superior vena cava and characteristic aneurysms of the pulmonary arteries.

MR imaging in the evaluation of the chest after uncomplicated median sternotomy.

Although complications of median sternotomy are infrequent, they are associated with high morbidity and mortality. Current imaging modalities have proved to be of limited value in the evaluation of these abnormalities. The search for more efficacious means of assessment is continual. The appearance of the thorax was evaluated in 10 patients who were undergoing median sternotomy for coronary artery bypass graft surgery. Three serial magnetic resonance (MR) imaging examinations were performed on each patient. These examinations included a baseline preoperative study and two postoperative studies. Each patient included in the study had an uncomplicated postoperative clinical course. Usual postoperative findings included pleural effusions, pulmonary parenchymal abnormalities, mediastinal edema, and pericardial effusions. On the basis of this limited study, the authors believe that MR imaging is a feasible means of evaluating the chest after surgery. An appreciation of the normal postoperative appearance is essential before complications can be reliably identified and characterized.

Cisplatin toxicity in cats.

Cisplatin (cis-diamminedichloroplatinum; Platinol, Bristol, Syracuse, NY) was administered to 11 cats, divided into three groups of experimental and clinical patients. In group 1, cisplatin was administered at a dose of 60 mg/m2 to four cats. In an attempt to avoid renal toxicity, saline diuresis was induced by administering 0.9% saline solution intravenously at a rate of 20 ml/kg/hr for 4 hours before and 2 hours after cisplatin administration. All four cats became dyspneic and died 48-96 hours after cisplatin administration. Postmortem findings included severe hydrothorax, pulmonary edema, and mediastinal edema. In group 2, four experimental cats entered a trial comparing the effects of saline diuresis and cisplatin (60 mg/m2) with the effects of saline diuresis and placebo (0.9% saline solution). The cats in the saline control group remained completely normal, while the cats that received cisplatin developed clinical signs and gross postmortem pulmonary changes identical to those in the first group of cats. Histopathologic examination showed that the alveolar septa were thickened and congested, and contained macrophages, occasional neutrophils, thrombi, and small foci of necrosis and fibrin. Microangiopathic changes were seen in the alveolar capillaries. In the third group, three additional cats were treated with a lower dose of cisplatin. Two cats that received 40 mg/m2 of cisplatin developed pulmonary changes similar to, but less severe than, those seen in the cats that received the higher dose of cisplatin. One cat treated with 20 mg/m2 of cisplatin showed no pulmonary changes ante mortem or post mortem. This series of 11 clinical and experimental cases identifies an apparent species-specific, dose-related, primary pulmonary toxicity of cisplatin in cats.

Transient Unilateral Hypoperfusion of the Lung following Mediastinoscopy

Two cases of pulmonary hypoperfusion occurring after mediastinoscopic examination were demonstrated on lung scans. In one case, this finding on the ninth day required a pulmonary angiographic study that yielded normal findings. Repeat lung scans were normal. We propose that localized mediastinal edema or bleeding after mediastinoscopic examination can produce defects of hypoperfusion, and we urge caution in the interpretation of lung scans up to nine days after mediastinoscopic examination.

The Review Of Pneumonectomyh for Advanced Pulmonary Tuberculosis

I have reviewed the results of 30 cases of pneumonectomy for advanced pulmonary tuberculosis in past two years and the summary of results is as follows:1) Recently, in Korea the cases of pneumonectomy for tuberculosis are gradually increased while the % of lobectomy and segmental resection has been decreased.2) According to the x-Ray findings all cases indicated for pneumonectomy are classified into 3groups.e,g, opaque, far extended and empyema group.3) The mortality was 6.6%, and of these death early dead was mainly caused by cardiorespiratory insufficiency while the late death was due to the respiratory insufficiency secondary to tuberculous spread of opposite lung.4) There was no complication of bronchofistula, but one case of empyema was occurred after 20days of operation due to wound infection.5) In most cases, postoperatively, it should be strictly observed the occurrence of mediastinal shift, anoxia and pulmonary edema. We have routinely preferred to apply the digitalization for about 5days preoperatively and aminophylline injection postoperatively.

The mediastinum in portal hypertension

<h2>Summary</h2> The radiological features of the mediastinum in portal hypertension have been analysed. A method of measurement of the diameter of the azygos vein using tomography is described. In thirty-six patients with portal hypertension, the mean diameter of the azygos vein, corrected to a standard patient weight of 140 lb., was 18 mm. (standard deviation 3 mm.). In a group of forty-eight patients without portal hypertension or any lesion known to cause azygos vein enlargement, the mean diameter of the weight standardised azygos vein was 14·2 mm. (standard deviation 2·6 mm.). There was no good correlation between the size of the azygos vein and the extent of the collateral circulation assessed by splenic venography or the size of the oesophageal varices demonstrated by barium swallow. There was no correlation between the clinical features of ascites, encephalopathy or gastro-intestinal bleeding and the size of the azygos vein. The width of the left paravertebral shadow was measured in forty patients with portal hypertension and in fifty-four control subjects. The width of the shadow is increased on the average in patients with portal hypertension, but it is not a reliable indication of the size of the hemiazygos veins. A very wide paravertebral shadow in a patient with fluid retention may be due to mediastinal oedema. Attention is drawn to the occurrence of other abnormal mediastinal shadows in patients with portal hypertension. Recognition of this is important in avoiding diagnostic errors.