Perforated gastric ulcer causing mediastinal emphysema: A case report

BACKGROUND Mediastinal emphysema is a condition in which air enters the mediastinum between the connective tissue spaces within the pleura for a variety of reasons.It can be spontaneous or secondary to chest trauma,esophageal perforation,medi-cally induced factors,etc.Its common symptoms are chest pain,tightness in the chest,and respiratory distress.Most mediastinal emphysema patients have mild symptoms,but severe mediastinal emphysema can cause respiratory and circulatory failure,resulting in serious consequences.CASE SUMMARY A 75-year-old man,living alone,presented with sudden onset of severe epigastric pain with chest tightness after drinking alcohol.Due to the remoteness of his residence and lack of neighbors,the patient was found by his nephew and brought to the hospital the next morning after the disease onset.Computed tomography(CT)showed free gas in the abdominal cavity,mediastinal emph-ysema,and subcutaneous pneumothorax.Upper gastrointestinal angiography showed that the esophageal mucosa was intact and the gastric antrum was perforated.Therefore,we chose to perform open gastric perforation repair on the patient under thoracic epidural anesthesia combined with intravenous anesthesia.An operative incision of the muscle layer of the patient's abdominal wall was made,and a large amount of subperitoneal gas was revealed.And a continued incision of the peritoneum revealed the presence of a perforation of approx-imately 0.5 cm in the gastric antrum,which we repaired after pathological examination.Postoperatively,the patient received high-flow oxygen and cough exercises.Chest CT was performed on the first and sixth postoperative days,and the mediastinal and subcutaneous gas was gradually reduced.CONCLUSION After gastric perforation,a large amount of free gas in the abdominal cavity can reach the mediastinum through the loose connective tissue at the esophageal hiatus of the diaphragm,and upper gastrointestinal angiography can clarify the site of perforation.In patients with mediastinal emphysema,open surgery avoids the elevation of the diaphragm caused by pneumoperitoneum compared to laparoscopic surgery and avoids increasing the mediastinal pressure.In addition,thoracic epidural anesthesia combined with intravenous anesthesia also avoids pressure on the mediastinum from mechanical ventilation.

Combining machine and deep transfer learning for mediastinal lymph node evaluation in patients with lung cancer

Background The prognosis and survival of patients with lung cancer are likely to deteriorate with metastasis.Using deep-learning in the detection of lymph node metastasis can facilitate the noninvasive calculation of the likelihood of such metastasis,thereby providing clinicians with crucial information to enhance diagnostic precision and ultimately improve patient survival and prognosis.Methods In total,623 eligible patients were recruited from two medical institutions.Seven deep learning models,namely Alex,GoogLeNet,Resnet18,Resnet101,Vgg16,Vgg19,and MobileNetv3(small),were utilized to extract deep image histological features.The dimensionality of the extracted features was then reduced using the Spearman correlation coefficient(r≥0.9)and Least Absolute Shrinkage and Selection Operator.Eleven machine learning methods,namely Support Vector Machine,K-nearest neighbor,Random Forest,Extra Trees,XGBoost,LightGBM,Naive Bayes,AdaBoost,Gradient Boosting Decision Tree,Linear Regression,and Multilayer Perceptron,were employed to construct classification prediction models for the filtered final features.The diagnostic performances of the models were assessed using various metrics,including accuracy,area under the receiver operating characteristic curve,sensitivity,specificity,positive predictive value,and negative predictive value.Calibration and decision-curve analyses were also performed.Results The present study demonstrated that using deep radiomic features extracted from Vgg16,in conjunction with a prediction model constructed via a linear regression algorithm,effectively distinguished the status of mediastinal lymph nodes in patients with lung cancer.The performance of the model was evaluated based on various metrics,including accuracy,area under the receiver operating characteristic curve,sensitivity,specificity,positive predictive value,and negative predictive value,which yielded values of 0.808,0.834,0.851,0.745,0.829,and 0.776,respectively.The validation set of the model was assessed using clinical decision curves,calibration curves,and confusion matrices,which collectively demonstrated the model's stability and accuracy.Conclusion In this study,information on the deep radiomics of Vgg16 was obtained from computed tomography images,and the linear regression method was able to accurately diagnose mediastinal lymph node metastases in patients with lung cancer.

Exploration and optimization of surgical techniques for laparoscopic transhiatal lower mediastinal lymph node dissection for adenocarcinoma of esophagogastric junction: A prospective IDEAL 2a study with qualitative design

Objective: To explore the change and feasibility of surgical techniques of laparoscopic transhiatal(TH)-lower mediastinal lymph node dissection(LMLND) for adenocarcinoma of the esophagogastric junction(AEG)according to Idea, Development, Exploration, Assessment, and Long-term follow-up(IDEAL) 2a standards.Methods: Patients diagnosed with AEG who underwent laparoscopic TH-LMLND were prospectively included from April 14, 2020, to March 26, 2021. Clinical and pathological information as well as surgical outcomes were quantitatively analyzed. Semistructured interviews with the surgeon after each operation were qualitatively analyzed.Results: Thirty-five patients were included. There were no cases of transition to open surgery, but three cases involved combination with transthoracic surgery. In qualitative analysis, 108 items under three main themes were detected: explosion, dissection, and reconstruction. Revised instruction was subsequently designed according to the change in surgical technique and the cognitive process behind it. Three patients had anastomotic leaks postoperatively, with one classified as Clavien-Dindo Ⅲa.Conclusions: The surgical technique of laparoscopic TH-LMLND is stable and feasible;further IDEAL 2b research is warranted.

Mediastinal lesions in children

The mediastinum is where thoracic lesions most frequently occur in young patients.The histological spectrum of diseases caused by the presence of several organs in the mediastinum is broad.Congenital lesions,infections,benign and malignant lesions,and vascular diseases are examples of lesions.Care should be taken to make the proper diagnosis at the time of diagnosis in order to initiate therapy promptly.Our task is currently made simpler by radiological imaging techniques.

Life-threatening delayed mediastinal and subcutaneous emphysema after general anesthesia in a rheumatoid arthritis patient: a case report

Background:Delayed mediastinal emphysema with subcutaneous emphysema after extubation is rarely reported in current literature.Symptomatic treatment is considered effective for management.Case presentation:We report a case of a 56-year-old female with longstanding rheumatoid arthritis under corticosteroid therapy who developed mediastinal emphysema with subcutaneous emphysema 2 days after recovering from general anesthesia for orthopedic surgery treating a femoral neck fracture.The patient received aggressive subcutaneous decompression and symptomatic management.Results:The patient’s condition improved after treatment.Based on computed tomography scan results,we hypothesize that the longstanding rheumatoid arthritis may have resulted in fragile lung tissue.Violent postoperative coughing likely caused rupture of small airways,leading to mediastinal emphysema.Conclusions:It is crucial to preoperatively assess the risk of airway injury in high-risk patients with longstanding rheumatoid arthritis.Delayed postoperative mediastinal emphysema should be carefully evaluated and managed aggressively to avoid exacerbation or life-threatening scenarios.Further research is warranted to elucidate the pathology and guide perioperative management in these patients.

Tuberculous esophagomediastinal fistula with concomitant mediastinal bronchial artery aneurysm-acute upper gastrointestinal bleeding: A case report

BACKGROUND Esophagomediastinal fistula is a very rare complication of tuberculosis in otherwise healthy adults, and mediastinal bronchial artery aneurysm is even rarer. In this case report, we describe a rare case of tuberculosis complication that presented with acute upper gastrointestinal(GI) bleeding. It also highlights the benefits of chest computed tomography(CT) as an excellent adjunct diagnostic tool to endoscopy and bronchoscopy and the role of trans-arterial embolization as a minimal invasive therapy alternative to surgery.CASE SUMMARY A 19-year-old medically free male patient presented with acute multiple episodes of hematemesis for 1 d. Upper GI endoscopy, bronchoscopy, and chest CT with IV contrast confirmed esophagomediastinal fistula with mediastinal bronchial artery aneurysm. After resuscitating patient with IV fluid and blood product transfusion, trans catheter embolization was performed for mediastinal bronchial artery aneurysm.CONCLUSION We successfully treated a patient with acute upper GI bleeding due to tuberculous esophagomediastinal fistula and mediastinal bronchial artery aneurysm using transcatheter coil embolization.

Clinical value of contrast-enhanced ultrasound in improving diagnostic accuracy rate of transthoracic biopsy of anteriormedial mediastinal lesions

Objective： To evaluate the clinical value of contrast-enhanced ultrasound（CEUS） in transthoracic biopsy of anterior-medial mediastinal lesions.Methods： A total of 123 patients with anterior or middle mediastinum lesions required ultrasound guided transthoracic biopsy for pathological diagnosis. Among them, 72 patients received CEUS examinations before biopsy. After CEUS, 8 patients were excluded from biopsy and the rest 64 patients underwent biopsy（CEUS group）. During the same period, 51 patients received biopsy without CEUS examination（US group）. The ultrasonography characteristics, the number of biopsy puncture attempts, diagnostic accuracy rate and the incidence of complications were recorded and compared between the two groups.Results： A large portion of necrosis area or superficial large vessels was found in 8 patients, so the biopsy was cancelled. The internal necrosis was demonstrated in 43.8% of the lesions in CEUS group and in 11.8% of US group（P0.001）. For thymic carcinoma, CEUS increased the detection rate of internal necrosis and pericardial effusion than conventional ultrasound（62.5% vs. 18.8%, P=0.012; 56.3% vs. 12.5%, P=0.023）. The average number of punctures in CEUS group and US group was 2.36±0.70 and 2.21±0.51 times, respectively（P0.05）. The diagnostic accuracy rate of biopsy in CEUS group（96.9%, 62/64） was significantly higher than that in US group（84.3%, 43/51）（P=0.022）. In US group, 2 patients suffered from mediastinal bleeding（3.9%）, while no major complications occurred in CEUS group.Conclusions： CEUS examination provided important information before transthoracic mediastinum biopsy and improved diagnostic accuracy rate in biopsy of anterior and middle mediastinum lesions than conventional ultrasound.

Carbon dioxide insufflation in esophageal endoscopic submucosal dissection reduces mediastinal emphysema: A randomized, double-blind, controlled trial

AIM To assess the efficacy of CO2 insufflation for reduction of mediastinal emphysema(ME) immediately after endoscopic submucosal dissection(ESD).METHODS A total of 46 patients who were to undergo esophageal ESD were randomly assigned to receive either CO2 insufflation(CO2 group, n = 24) or air insufflation(Air group, n = 22). Computed tomography(CT) was carried out immediately after ESD and the next morning. Pain and abdominal distention were chronologically recorded using a 100-mm visual analogue scale(VAS). The volume of residual gas in the digestive tract was measured using CT imaging. RESULTS The incidence of ME immediately after ESD in the CO2 group was significantly lower than that in the Air group(17% vs 55%, P = 0.012). The incidence of ME the next morning was 8.3% vs 32% respectively(P= 0.066). There were no differences in pain scores or distention scores at any post-procedure time points. The volume of residual gas in the digestive tract immediately after ESD was significantly smaller in the CO2 group than that in the Air group(808 m L vs 1173 m L, P = 0.013).CONCLUSION CO2 insufflation during esophageal ESD significantly reduced postprocedural ME. CO2 insufflation also reduced the volume of residual gas in the digestive tract immediately after ESD, but not the VAS scores of pain and distention.

Mediastinal node staging by positron emission tomographycomputed tomography and selective endoscopic ultrasound with fine needle aspiration for patients with upper gastrointestinal cancer:Results from a regional centre

AIM To investigate the impact of endoscopic ultrasound-guided fine-needle aspiration(EUS-FNA) and positron emission tomography-computed tomography(PET-CT) in the nodal staging of upper gastrointestinal(GI) cancer in a tertiary referral centre.METHODS We performed a retrospective review of prospectively recorded data held on all patients with a diagnosis of upper GI cancer made between January 2009 and December 2015. Only those patients who had both a PET-CT and EUS with FNA sampling of a mediastinal node distant from the primary tumour were included. Using a positive EUS-FNA result as the gold standard for lymph node involvement, the sensitivity, specificity, positive and negative predictive values(PPV and NPV) and accuracy of PET-CT in the staging of mediastinal lymph nodes were calculated. The impact on therapeutic strategy of adding EUS-FNA to PET-CT was assessed.RESULTS One hundred and twenty one patients were included. Sixty nine patients had a diagnosis of oesophageal adenocarcinoma(Thirty one of whom were junctional), forty eight had oesophageal squamous cell carcinoma and four had gastric adenocarcinoma. The FNA results were inadequate in eleven cases and the PET-CT findings were indeterminate in two cases, therefore thirteen patients(10.7%) were excluded from further analysis. There was concordance between PET-CT and EUS-FNA findings in seventy one of the remaining one hundred and eight patients(65.7%). The sensitivity, specificity, PPV and NPV values of PET-CT were 92.5%, 50%, 52.1% and 91.9% respectively. There was discordance between PET-CT and EUS-FNA findings in thirty seven out of one hundred and eight patients(34.3%). MDT discussion led to a radical treatment pathway in twenty seven of these cases, after the final tumour stage was altered as a direct consequence of the EUS-FNA findings. Of these patients, fourteen(51.9%) experienced clinical remission of a median of nine months(range three to forty two months). CONCLUSION EUS-FNA leads to altered staging of upper GI cancer, resulting in more patients receiving radical treatment that would have been the case using PET-CT staging alone.

Incidence and treatment of mediastinal leakage after esophagectomy:Insights from the multicenter study on mediastinal leaks

BACKGROUND Mediastinal leakage(ML) is one of the most feared complications of esophagectomy. A standard strategy for its diagnosis and treatment has beendifficult to establish because of the great variability in their incidence and mortality rates reported in the existing series.AIM To assess the incidence, predictive factors, treatment, and associated mortality rate of mediastinal leakage using the standardized definition of mediastinal leaks recently proposed by the Esophagectomy Complications Consensus Group(ECCG).METHODS Seven Italian surgical centers(five high-volume, two low-volume) affiliated with the Italian Society for the Study of Esophageal Diseases designed and implemented a retrospective study including all esophagectomies(n = 501) with intrathoracic esophagogastric anastomosis performed from 2014 to 2017.Anastomotic MLs were defined according to the classification recently proposed by the ECCG.RESULTS Fifty-nine cases of ML were recorded, yielding an overall incidence of 11.8%(95%CI: 9.1%-14.9%). The surgical approach significantly influenced the occurrence of ML: the proportion of leakage was 10.5% and 9% after open and hybrid esophagectomy(HE), respectively, and doubled(20%) after totally minimally invasive esophagectomy(TMIE)(P = 0.016). No other predictive factors were found. The 30-and 90-d overall mortality rates were 1.4% and 3.2%,respectively; the 30-and 90-d leak-related mortality rates were 5.1% and 10.2%,respectively; the 90-d mortality rates for TMIE and HE were 5.9% and 1.8%,respectively. Endoscopy was the first-line treatment in 49% of ML cases, with the need for retreatment in 17.2% of cases. Surgery was needed in 44.1% of ML cases.Endoscopic treatment had the lowest mortality rate(6.9%). Removal of the gastric tube with stoma formation was necessary in 8(13.6%) cases.CONCLUSION The incidence of ML after esophagectomy was high mainly in the TMIE group.However, the general and specific(leak-related) mortality rates were low. Early treatment(surgical or endoscopic) of severe leaks is mandatory to limit related mortality.

Transarterial embolization of metastatic mediastinal hepatocellular carcinoma

This paper introduces an innovative treatment for extrahepatic metastasis of hepatocellular carcinoma. A 71-yearold patient had a stable liver condition following treatment for hepatocellular carcinoma, but later developed symptomatic mediastinal metastasis. This rapidly growing mediastinal mass induced symptoms including cough and hoarseness. Serial sessions of transarterial embolization (TAE) successfully controlled this mediastinal mass with limited side effects. The patient's survival time since the initial diagnosis of the mediastinal hepatocellular carcinoma was 32 mo, significantly longer than the 12 mo mean survival period of patients with similar diagnoses: metastatic hepatocellular carcinoma and a liver condition with a Child-Pugh class A score. Currently, oral sorafenib is the treatment of choice for metastatic hepatocellular carcinoma. Recentstudies indicate that locoregional treatment of extrahepatic metastasis of hepatocellular carcinomas might also significantly improve the prognosis in patients with their primary hepatic lesions under control. Many effective locoregional therapies for extrahepatic metastasis, including radiation and surgical resection, may provide palliative effects for hepatocellular carcinoma-associated mediastinal metastasis. This case report demonstrates that TAE of metastatic mediastinal hepatocellular carcinoma provided this patient with tumor control and increased survival time. This finding is important as it can potentially provide an alternative treatment option for patients with similar symptoms and diagnoses.

Efficacy of contrast-enhanced ultrasound-guided percutaneous core needle biopsy in anterior mediastinal masses

Objective:To evaluate the efficacy and safety of percutaneous core needle biopsy(PCNB)using ultrasound(US)-guided and contrast-enhanced ultrasound(CEUS)-guided procedures for anterior mediastinal masses(AMMs).Methods:In total,284 consecutive patients(166 men,118 women;mean age,43.0±18.4 years)who underwent PCNB for AMMs were enrolled.Patients were divided into the US-guided group(n=133)and the CEUS-guided group(n=151).PCNB was performed using a core needle(16-gauge or 18-gauge).Internal necrosis,diagnostic yield,and diagnostic accuracy were compared between the two groups.Results:The predominant final diagnosis of the cases in this study was thymoma(29.7%),lymphoma(20.5%),thymic carcinoma(13.3%),and germ cell tumour(13.3%),respectively.There was no significant difference in patient age,sex,number of percutaneous biopsies,or display rate of internal necrosis on conventional US between the two groups.The rate of internal necrosis of the lesions was significantly higher after contrast agent injection(72.2%vs.41.7%;P<0.001).The CEUS-guided group had a higher diagnostic yield than the US-guided group(100%vs.89.5%,P<0.001).There was no significant difference between the diagnostic accuracy of the CEUSguided and US-guided groups(97.3%vs.97.4%;P=1.000).None of the patients experienced adverse reactions or complications after US-guided or CEUS-guided PCNB.Conclusions:CEUS-guided PCNB can improve the diagnostic yield by optimizing the biopsy procedure.

Mediastinal small cell carcinoma with liver and bone marrow metastasis, mimicking lymphoma

Primary mediastinal neuroendocrine tumors are a rare malignancy that accounts for < 10% of all mediastinal tumors. The case presented here involves a 52-yearold man who had been suffering for 3 mo from chronic cough, anorexia and substantial weight loss, as well as 2 wk of jaundice prior to his admission. A computed tomography scan showed a 4.3 cm × 6.6 cm mediastinal mass with multiple liver nodules scattered along both hepatic lobes. Endoscopic ultrasound showed a large heterogeneous hypoechoic mass at the mediastinum with multiple target-like nodules in the liver. Fine-needle aspiration specimens revealed numerous, small, round cells with hyperchromatic nuclei, scarce cytoplasm, and frequent mitotic features. Immunohistochemical study revealed positive results for AE1/AE3, CD56 and chromogranin A, with negative findings for synaptophysin, CK20, vimentin, CK8/18 and CD45. The patient was subsequently diagnosed with a poorly differentiated neuroendocrine carcinoma, small cell type. A bone marrow biopsy also revealed extensive involvement by the carcinoma.

Solitary mediastinal lymph node recurrence after curative resection of colon cancer

We report two cases of solitary mediastinal lymph node recurrence after colon cancer resection. Both cases had para-aortic lymph node metastasis at the time of initial surgery and received adjuvant chemotherapy for 4 years in case 1 and 18 mo in case 2. The time to recurrence was more than 8 years in both cases. After resection of the recurrent tumor, the patient is doing well with no recurrence for 6 years in case 1 and 4 mo in case 2. Patients should be followed up after colon cancer surgery considering the possibility of solitary mediastinal lymph node recurrence if they had para-aortic node metastasis at the time of initial surgery.

Malignant histiocytosis associated with mediastinal germ cell tumor:A case report

BACKGROUND Germ cell tumors(GCTs)account for 2%of human malignancies but are the most common malignant tumors among males aged 15-35.Since 1983,an association between mediastinal GCT(MGCT)and hematologic malignancies has been recognized.CASE SUMMARY We report a case in which malignant histiocytosis was associated with mediastinal GCTs.The clinical data of a male patient with MGCT admitted to Beijing Children's Hospital were collected retrospectively.The patient was first diagnosed according to imaging and pathological features as having MGCT,and was treated with surgery and chemotherapy.One year after stopping chemotherapy,imaging showed metastases in the right supraclavicular,mediastinum,hilar region and retroperitoneal lymph node,right pleura,right lung,and right para-cardiac margin.Pathological diagnosis of the liver nodular and hilar lymph nodes included systemic juvenile xanthogranuloma and Rosai-Dorfman lesions with malignant transformation(i.e.,morphological characteristics and immunophenotype of histiocytic sarcoma).Following diagnosis,the patient accepted chemotherapy with vindesine,cytarabine and dexamethasone.Positron emission tomography–computed tomography showed partial remission.The patient was followed-up for 10 mo after the diagnosis of malignant histiocytosis,and no sign of progression or relapse was observed.CONCLUSION Physicians should recognize the possibility of hematologic malignancies being associated with MGCT.Suitable sites should be selected for pathological examination.

Uniportal video-assisted thoracoscopic surgery for complex mediastinal mature teratoma:A case report

BACKGROUND Mediastinal mature teratoma is the most common histological type of primary extragonadal germ cell tumor.In this report,we describe a rare case of giant mature teratoma located primarily in the anterior mediastinum and causing partial atelectasis of the upper and middle lobes of the right lung,as well as extrinsic compression of the right atrium.CASE SUMMARY A 31-year-old male with a giant mediastinal mature teratoma presented with progressive exertional dyspnea and chest pain for 1 mo.Computed tomography of the chest indicated the diagnosis of anterior mediastinal teratoma.The patient underwent right uniportal anterior approach video-assisted thoracoscopic surgery(VATS).En bloc resection of the giant teratoma,wedge resection of the upper and middle lobes of the right lung,resection of the thymus and partial excision of the pericardium were successfully performed.The pathological diagnosis revealed a mature cystic teratoma with foreign-body reaction that was closely related to the right lung,atrium dextrum,superior vena cava and ascending aorta.An atrophic thymic tissue was also discovered at the external teratoma surface.The patient was discharged on postoperative day 7.CONCLUSION This is the first report of the use of uniportal VATS for complete resection of a teratoma in combination with wedge resection of the right upper and middle lung lobes and partial resection of the pericardium.

Video-assisted Thoracoscopic Surgery for the Treatment of Mediastinal Lymph Node Tuberculous Abscesses

The mediastinal lymph node tuberculous abscesses（MLNTAs） are secondary to mediastinal tuberculous lymphadenitis. Surgical excision is often required when cold abscesses form. This study was aimed to examine video-assisted thoracoscopic surgery（VATS） for the treatment of MLNTA. Clinical data of 16 MLNTA patients who were treated in our hospital between December 1, 2013 and December 1, 2015 were retrospectively analyzed. All of the patients underwent the radical debridement and drainage of abscesses, and intrathoracic lesions were removed by VATS. They were also administered the intensified anti-tuberculosis treatment（ATT）, and engaged in normal physical activity and follow-up for 3 to 6 months. The results showed that VATS was successfully attempted in all of the 16 MLNTA patients and they all had good recovery. Two patients developed complications after surgery, with one patient developing recurrent laryngeal nerve injury, and the other reporting poor wound healing. It was concluded that VATS is easy to perform, and safe, and has high rates of success and relatively few side-effects when used to treat MLNTA.

Giant Mediastinal Neurofibroma in a Child with Neurofibromatosis Type I

Aim: There are a variety of malignant tumors related to neurofibromatosis type 1 (NF1). This report describes a rare pediatric NF1 case with an unresectable giant mediastinal tumor. Case: A 6-year-old girl with wheezing was admitted to our institution for the further evaluation of a right mediastinal mass on plain chest radiography. On examination, there were multiple café au lait spots mainly on the trunk, and a well-defined, immobile, painless mass was palpable on her neck. The mediastinal lesion was detected as nonuniform mass surrounding the aortic arch, pulmonary artery, and right main bronchus on the contrast-enhanced CT and MRI. Open biopsy was useful to rule out malignancy and revealed neurofibroma, and contributed to follow up and treatment. Discussion: Open biopsy was useful to rule out malignancy, such as malignant peripheral nerve sheath tumor, revealed neurofibroma, and also contributed to follow up and treatment. The authors report successful management by open biopsy and discuss several clinical points regarding mediastinal neurofibroma for NF1.

Subcutaneous Dissociative Conscious Sedation (sDCS) a New Approach to Compromised Airway in Mediastinal Masses

Purpose: Anesthesia and airway management for mediastinal masses are challenging and are accompanied by mortality and morbidity. Avoiding the loss of airway muscular tone in mediastinal masses has been confirmed necessary to avoid airway collapse. Sufficient spontaneous ventilation is of paramount importance in order to reduce the rate of mortality and morbidity. Various anesthetics and anesthesia techniques have been used for maintaining spontaneous ventilation and patent airway. In this report, a successful double lumen endobronchial intubation using “subcutaneous dissociative conscious sedation” as a novel method in the management of compromised airway (a case of a mediastinal mass) is presented. Clinical features: A 42 year- old, 62 Kg man was presented for an open biopsy of a middle mediastinal mass. The patient had a history of chest pain, dyspnea, cough, fever and sweats for 2 months. Regarding to the life threatening nature of mediastinal masses resulting from unpredictable events of airway obstruction and the reported cases of deaths after induction of anesthesia in patients with mediastinal masses and regarding to the importance of not losing muscular tone and keeping airway tone intact in patients with mediastinal masses” subcutaneous Dissociative Conscious Sedation (a novel method of anesthesia)”was selected in order to guarantee the safety of the patient and keep the airway secure. Conclusion: Owing to the characteristics of the “subcutaneous dissociative conscious sedation” this method is suggested as an appropriate substitute to general anesthesia for Endobronchial Double Lumen Intubation in mediastinal masses and compromised airway.

Posterior Mediastinal Mature Teratoma: A Case Report and Literature Review

Mediastinal mature teratoma is the most common form of germ cell tumors, often located in the anterior mediastinum. A posterior mediastinum location has rarely been described. We report a case of a posterior mediastinal mature teratoma in a 37-year-old patient and a literature review, through which we describe the diagnostic and therapeutic difficulties inherent in this particular location of these tumors.