Clinical Application Of Ultrasonography Diagnosis And Ultrasound Guided Automatic Biopsy In Mediastinal Tumors

Mediastinal tumor is the tumor that comes from mediastinum with the exception of trachea, esophago, heart and great vessels. It is a common disease in chest surgery, and the incidence of it shows a constant increasing tendency.Due to the complex interior tissue structure of the mediastinum, various benign and malignant tumors could proceed. The imaging diagnosis for mediastinal tumor mainly relies on X-ray or CT, in the meanwhile, with the development of imaging technology, ultrasonic inspection without radiation damage has been applied in practice. In the half past century, ultrasonic technology and equipment have developed in a fast speed, while the category and function of ultrasonic probe have been perfected, therefore, diagnosis for mediastinal tumor has been deeply applied with significant advantages and has become an important supplementary measure in other diagnosing techniques. The application of color doppler ultrasonography make it become true to dynamically observe the tumor's location, size, internal echo, and with detection technology of color doppler flow imaging, to observe the relationship between mediastinum mass and heart or great vessels, furthermore, to detect the bloodstream disposition in tumor, and to measure the index number on resistance of arterial blood flow. This technology provide so affluent imaging information for clinical diagnosis that it cannot be replaced. However, the ultrasonic inspection has some limitation in diagnosing whether the mediastinal tumor is innocent or malig, and a preoperative identified pathological diagnosis of mediastinal tumor has significant influence on clinical therapeutic regimen designing and prognosis previewing, therefore, mediastinal tumor pricking biopsy has become a necessary measurement for this purpose.The biopsy of mediastinal lesions, conducted by ultrasound guided percutaneous puncture, applies in a manual biopsy way in the early stage, that is, ultrasound guided cutting biopsy (UGCB) andultrasound guided needle biopsy (UGNB). The invention of automatic biopsy device (ABD) turn the pricking technique from a hand movement to an automatic one. Ultrasound guided automatic biopsy (USGAB) technique is now available to draw the materials accurately and quickly, with the advantages of taking high quality materials, causing less pain with minimal invasion, being safe, and having a high masculine rate of pathologic diagnosis. Accordingly, it has been widely applied in clinical treatment. This thesis conducts a survey on the sonogram characteristics of 50 cases suffering from mediastinal tumor, and 48 patients in the treatment of USGAB, aiming at assessing the clinical value of the application of ultrasonography diagnosis of mediastinal tumor and USGAB technique to the preoperative diagnosis of mediastinal tumor.This thesis chooses 52 cases with 31 male patients and 21 female ones, who has been diagnosed as mediastinal occupaying through X-ray,CT,MRI check from 2007, May to 2009, March. Color doppler ultrasonography can be conducted with color doppler imaging(CDI), which is Sequoia 512 produced by Siemens and Sonosope SSI-1000 produced by Kaili Company, using the probe frequency ranging from 2.5 to 3.75MHz,while 5.0 to 7.5 MHz at the superficial place. 50 cases can clearly or almost clearly show focus of infection. Among these cases, one cannot undergo USGAB check because the affection has been covered by great vessels via compression and circumvolution aortic arch, the other one suffers from pure cystic lesion, preliminary diagnosis is concluded combined with other imaging check, then it is confirmed as epidermoid cyst according to the operation and pathological analysis. The rest 48 cases apply automatic biopsy gun and 16-21G sulcated tru-cut needles(Bard American) to undergo USGAB.As a result, the display rate of the color Doppler ultrasonography reaches 96.2% (50/52)among those 52 cases, 35 cases with tumor coming from anterior mediastinum, 8 from middle mediastinum, and 7 from posterior mediastinum. Among them one case refers to pure cystic lesion, 38 cases solid lesions, and 11 cases cystic-solid lesions. 3 cases show calcification in the lesion (with 1 case of thymoma and 2 cases of cystic-solid teratoma). Some of the mediastinal tumor can be given a inferential diagnosis according to its place and specific ultrasonogram. 48 cases undergone USGAB check show 93.8% (45/48)of masculine rate in pathologic diagnosis, including 13 cases of thymoma, 7 cases of teratoma, 9 cases of malignant lymphoma, 1 case of intrathoracic nodular goiter, 6 cases of Pulmonary cancinoma of mediastinal type, 1 case of glandular phthisis, 4 cases of metastatic carcinoma, 2 cases of neurilemmoma, 1 case of neurofibroma, and 1 case of neuroblastoma. Among them 17 case is of benign tumor, 27 case is of malignant tumor, and 1 is of tuberculosis. There were 3 patients who didn't have definite pathologic findings.The inconclusive pathological diagnosis was made in 1 of 48 cases (2.1%). Another 2 cases,who were made in 2 of 48 cases (4.2%),didn't achieved pathological types because the most of samples were necrotic tissue and little tumor tissues. 3 cases has been confirmed of lymphoma,cystic degeneration of thymoma ,cystic teratoma after operations. Neither of the 48 being punctured cases showed complication.Based on the command of normal method in mediastinum lession by ultrasonography and familiarity with tumor's various clinical features and ultrasonogram , color doppler ultrasonography can give out a level diagnosis on most tumor of anterior mediastinum and part of the middle and posterior mediastinum, and therefore quickly judge the tumor's physical property (cyst-solid). In the meanwhile, it can imply the diagnosis distinguishing the benign or malignant tumor according to the tumor's ultrasonogram, relations with surrounding tissues, and indirect signs such as pericardial effusion and pleural effussion. Color doppler ultrasonography, compared with other checking methods, is of the advantages such as being real-time, cheap, without radioaction damage, and repeatable. It is important that color doppler ultrasonography can dynamically observe the tumor's morphological characteristics and the interior blood supply, which is significant for enriching imaging check information. However, body surface ultrasonography has its shortcoming in dealing with minor mediastinal occupying lesion, especially the substernal,so it should be combined with other imaging check measures to make diagosis.Ultrasound guided automatic biopsy of mediastinal tumor can provide an accurate puncture point, and real-time monitoring of needle punctured into the direction and depth, which is easy to operate, based on high accuracy. In this study ,USGAB has been conducted on the 48 cases of patients who needs clarified preoperative pathological nature. Based on the local relationship between tumor and heart and great vessels, ultrasound guidance determines the location of the needle by avoiding the complex structure mentioned above, ensuring the safety of puncture and improving success rate. USGAB, using automatic ejection device to release tru-cut needles of organizations, can quickly get access to the lesion for a complete organization strip, and meet the requirements of pathological section. Compared with previous manual biopsy technique, USGAB has a higher positive rate of pathological diagnosis. Compared with X-ray and CT-guided biopsy it is easier to operate, safer, and more accurate without radioactive damage.While compared with Mediastino- scope, it causes less pain, trauma, and fewer complications. Patients with mediastinal tumor get clear pathological diagnoses by USGAB, which provide the best treatment for clinical programs and a reliable prognosis, avoiding unnecessary thoracic exploration.In summary, the ultrasonography diagnosis of mediastinal tumor , basde on their respective predilection site, combined with mass ultrasonogram features and clinical symptoms, may make a preliminary dignosis and differential diagnosis; ultrasound guided automatic biopsy of mediastinal tumor is a safe, reliable, simple and quick biopsy technology, which may provide a higher positive rate of pathological diagnosis, and it is a effective way for clinical diagnosis of mediastinal tumor.