Myung Hoon Na

Clinical Features of Deep Neck Infections and Predisposing Factors for Mediastinal Extension

Background Deep neck infections (DNI) can originate from infection in the potential spaces and fascial planes of the neck. DNI can be managed without surgery, but there are cases that need surgical treatment, especially in the case of mediastinal involvement. The aim of this study is to identify clinical features of DNI and analyze the predisposing factors for mediastinal extension. Materials and Methods We reviewed medical records of 56 patients suffering from DNI who underwent cervical drainage only (CD group) and those who underwent cervical drainage combined with mediastinal drainage for descending necrotizing mediastinitis (MD group) from August 2003 to May 2009 and compared the clinical features of each group and the predisposing factors for mediastinal extension. Results Forty-four out of the 56 patients underwent cervical drainage only (79%) and 12 patients needed both cervical and mediastinal drainage (21%). There were no differences between the two groups in gender (p=0.28), but the MD group was older than the CD group (CD group, 44.2±23.2 years; MD group, 55.6±12.1 years; p=0.03). The MD group had a higher rate of co-morbidity than the CD group (p=0.04). The CD group involved more than two spaces in 14 cases (32%) and retropharyngeal involvement in 12 cases (27%). The MD group involved more than two spaces in 11 cases (92%) and retropharyngeal involvement in 12 cases (100%). Organism identification took place in 28 cases (64%) of the CD group and 3 cases of (25%) the MD group (p=0.02). The mean hospital stay of the CD group was 21.5±15.9 days and that of the MD group was 41.4±29.4 days (p=0.04). Conclusion The predisposing factors of mediastinal extension in DNI were older age, involvement of two or more spaces, especially including the retropharyngeal space, and more comorbidities. The MD group had a longer hospital stay, higher mortality, and more failure to identify causative organisms of causative organisms than the CD group.

The C-terminus of Hsp70-Interacting Protein Promotes Met Receptor Degradation

Introduction: The tyrosine kinase Met receptor regulates a complex array of cellular behaviors known collectively as invasive growth. Although essential for normal development and wound repair, this pathway is frequently deregulated in tumors to promote their growth, motility, and invasion. Accordingly, Met is overexpressed in a variety of human tumors, and this aberrant expression correlates with a poor patient prognosis. Previous studies have shown that Met receptor levels are governed in part by Cbl-mediated ubiquitination and degradation, and the uncoupling of Met from this pathway promotes its transforming activity. Methods: Here, we describe a novel mechanism of Met degradation in Non Small Cell Lung Cancer Cells and HeLa cells using western blot, immunocytochemistry, immunoprecipitation assay, invasion assay, cell viability assay and in vivo tumor growth model. Results: Met receptor interacted with the C-terminus of heat shock protein 70-interacting protein (CHIP), leading to proteasomal degradation of the receptor in vitro. In addition, CHIP overexpression destabilized endogenous Met receptor in lung cancer cells, whereas CHIP knockdown increased Met receptor expression, indicating an essential role for CHIP in the regulation of Met degradation. CHIP overexpression inhibited Met-mediated lung cancer cell growth and invasion. Finally, we confirmed these results by tumor xenograft model. Conclusion: Based on these findings, we conclude that CHIP is a suppressor of Met function, serving to regulate cellular receptor levels by promoting Met receptor degradation.

Benign Metastasizing Leiomyoma: Metastasis to Rib and Vertebra

Benign metastasizing leiomyoma is very rare and characterized by the presence of pelvic, peritoneal, nodal, or pulmonary nodules in women with a history of uterine leiomyomas. We report a case of benign metastasizing leiomyoma in a 30-year-old woman who had undergone a prior myomectomy due to uterine cellular leiomyoma 3 years earlier. The patient had a mass on the right sixth rib and 2 masses in the sixth thoracic vertebra. Pathologically, these masses were diagnosed as cellular leiomyomas. Estrogen and progesterone receptors were both positive in the metastatic tumors as well as in the uterine leiomyomas. The diagnosis of benign metastasizing leiomyoma can only be made after careful examination of the primary tumor to exclude small foci of malignant change.

An Isolated True Aneurysm of the Superficial Femoral Artery in a Young Woman - A case report -

A 39-year-old woman was admitted to the hospital due to a pulsatile mass on her right inner thigh that was evident for two months. She did not exhibit any risk factors of atherosclerosis, no evidence of vasculitis, or any signs of previous trauma history. Ultrasound and computed tomography revealed an adult fist-sized aneurysm on the distal superficial femoral artery. The aneurysm was resected and peripheral circulation was restored with the interposition of a saphenous vein graft. The resected aneurysm had three layers that showed atherosclerosis on histological examination.

Stress-induced Cardiomyopathy during Pulmonary Resection (Takotsubo Syndrome) − A case report −

Stress-induced cardiomyopathy is caused by emotional or physical stressors and mimics acute myocardial infarction, though Stress-induced cardiomyopathy is characterized by reversible left ventricular (LV) apical ballooning in the absence of significant coronary artery disease. We describe a 51-year-old male who underwent left upper lobectomy for non-small cell lung cancer, and during which cardiogenic arrest occurred due to stress-induced cardiomyopathy, successfully managed by intra-aortic balloon pumping and extracorporeal membrane oxygenation.

Pulmonary Artery Angiosarcoma Confused with Acute Pulmonary Thromboembolism: Focusing on Clinical and Echocardiographic Features in the Differentiation of Two Categories

Although pulmonary artery angiosarcoma is rare, it can be misdiagnosed as pulmonary embolism because of its similar clinical and diagnostic features. The diagnosis is often delayed and the misdiagnosis brings unnecessary treatment. Because we made a wrong diagnosis of pulmonary artery angiosarcoma as an acute pulmonary embolism, we did thrombolytic therapy which could be dangerous to the patient. In this case report, we focused on the clinical and echocardiographic features of pulmonary artery angiosarcoma which can be used in differentiating the diagnosis from pulmonary embolism.

Acute ST-Segment Elevation Myocardial Infarction Due to a Huge Floating Thrombus Mimicking a Myxoma in the Left Atrium

Acute ST-segment elevation myocardial infarction occurs when the blood supply to a coronary artery is completely interrupted. The most common cause of the abrupt occlusion of a coronary artery is the rupture of a vulnerable atherosclerotic plaque. However, embolisms from any sources can be another cause of abrupt coronary obstruction. The authors report a case of acute ST-segment elevation myocardial infarction caused by a huge left atrial thrombus mimicking a myxoma.

Classic Peripheral Signs of Subacute Bacterial Endocarditis

A 50-year-old female patient with visual disturbances was referred for further evaluation of a heart murmur. Fundoscopy revealed a Roth spot in both eyes. A physical examination showed peripheral signs of infective endocarditis, including Osler nodes, Janeway lesions, and splinter hemorrhages. Our preoperative diagnosis was subacute bacterial endocarditis with severe aortic regurgitation. The patient underwent aortic valve replacement and was treated with intravenous antibiotics for 6 weeks postoperatively. The patient made a remarkable recovery and was discharged without complications. We report this case of subacute endocarditis with all 4 classic peripheral signs in a patient who presented with visual disturbance.

Outcomes of the Tower Crane Technique with a 15-mm Trocar in Primary Spontaneous Pneumothorax

Background Video-assisted thoracoscopic surgery (VATS) pulmonary wedge resection has emerged as the standard treatment for primary spontaneous pneumothorax. Recently, single-port VATS has been introduced and is now widely performed. This study aimed to evaluate the outcomes of the Tower crane technique as novel technique using a 15-mm trocar and anchoring suture in primary spontaneous pneumothorax. Methods Patients who underwent single-port VATS wedge resection in Chungnam National University Hospital from April 2012 to March 2014 were enrolled. The medical records of the enrolled patients were reviewed retrospectively. Results A total of 1,251 patients were diagnosed with pneumothorax during this period, 270 of whom underwent VATS wedge resection. Fifty-two of those operations were single-port VATS wedge resections for primary spontaneous pneumothorax performed by a single surgeon. The median age of the patients was 19.3±11.5 years old, and 43 of the patients were male. The median duration of chest tube drainage following the operation was 2.3±1.3 days, and mean postoperative hospital stay was 3.2±1.3 days. Prolonged air leakage for more than three days following the operation was observed in one patient. The mean duration of follow-up was 18.7±6.1 months, with a recurrence rate of 3.8%. Conclusion The tower crane technique with a 15-mm trocar may be a promising treatment modality for patients presenting with primary spontaneous pneumothorax.

In Vivo Neuroprotective Effect of Histidine-Tryptophan-Ketoglutarate Solution in an Ischemia/Reperfusion Spinal Cord Injury Animal Model.

Background Paraplegia is a devastating complication following operations on the thoracoabdominal aorta. We investigated whether histidine-tryptophan-ketoglutarate (HTK) solution could reduce the extent of ischemia/reperfusion (IR) spinal cord injuries in a rat model using a direct delivery method. Methods Twenty-four Sprague-Dawley male rats were randomly divided into four groups. The sham group (n=6) underwent a sham operation, the IR group (n=6) underwent only an aortic occlusion, the saline infusion group (saline group, n=6) underwent an aortic occlusion and direct infusion of cold saline into the occluded aortic segment, and the HTK infusion group (HTK group, n=6) underwent an aortic occlusion and direct infusion of cold HTK solution into the occluded aortic segment. An IR spinal cord injury was induced by transabdominal clamping of the aorta distally to the left renal artery and proximally to the aortic bifurcation for 60 minutes. A neurological evaluation of locomotor function was performed using the modified Tarlov score after 48 hours of reperfusion. The spinal cord was harvested for histopathological and immunohistochemical examinations. Results The spinal cord IR model using direct drug delivery in rats was highly reproducible. The Tarlov score was 4.0 in the sham group, 1.17±0.75 in the IR group, 1.33±1.03 in the saline group, and 2.67±0.81 in the HTK group (p=0.04). The histopathological analysis of the HTK group showed reduced neuronal cell death. Conclusion Direct infusion of cold HTK solution into the occluded aortic segment may reduce the extent of spinal cord injuries in an IR model in rats.