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991.
OBJECTIVES: The maxillary line is a mucosal projection along the lateral nasal wall that serves as a landmark for endoscopic sinus and orbital procedures. The anatomic relations of this structure are not well described. We sought to define the anatomy of the maxillary line and explore its clinical utility. STUDY DESIGN: Cadaver dissection/case series. METHODS: Twenty-five cadaveric nasal specimens were dissected. Extranasal and intranasal measurements of structures including the lacrimal crests, sac and duct, the suture line between the maxillary and lacrimal bones, and the maxillary sinus ostium were taken. The mid-point of the maxillary line, termed the "M point," was used for reference. The distance from the nasal sill to the M point was measured in 30 consecutive clinic patients. RESULTS: The maxillary line corresponded intranasally to the junction of the uncinate and maxilla and extranasally to the suture line between the lacrimal bone and maxilla within the lacrimal fossa. This suture was approximately half way between the anterior and posterior crests. Axially, the plane of the M point corresponded to the superior margin of the maxillary sinus ostium posteriorly (average 10 mm) and was just inferior to the lacrimal sac-duct junction anteriorly. In live subjects, the M point was approximately 3.9 cm from the nasal sill in women and 4.8 cm in men. CONCLUSION: Understanding the conserved relationships of the maxillary line and M point with adjacent nasal and orbital structures will ensure the complete removal of the uncinate process during uncinectomy and promote safe and ample exposure of the lacrimal sac during endoscopic dacryocystorhinostomy.  相似文献   
992.
OBJECTIVES/HYPOTHESIS: The objective was to investigate the functional and histological properties of surgical procedures using a new carbon dioxide (CO2) laser fiber. STUDY DESIGN: In vitro and in vivo animal models. METHODS: In vitro experiments using porcine true vocal cord and arytenoid cartilage were designed to study the histological effects of using a photonic band-gap fiber assembly for CO2 laser energy delivery. Continuous and pulsed-wave settings at different wattages were tested. In vivo endoscopic surgery on canine larynges and buccal mucosa were performed to examine functional and short-term healing when performing photonic band-gap fiber assembly-assisted laser surgery. RESULTS: In vitro experiments showed consistent cutting with the photonic band-gap fiber assembly using either straight or 90 degrees bent-tip fibers. The surrounding tissue in these experiments showed little collateral thermal damage with the average range of thermal width from 14.1 to 18.8 microm in vocal cords and from 5.2 to 10.5 microm in cartilage. Similarly, thermal depth ranged from 28.0 to 350.0 microm in vocal cords and from 269.7 to 739.6 microm in cartilage. In vivo experiments demonstrated ease in maneuvering and flexibility for cutting. There was minimal blood loss, smoke plume, or carbonaceous debris. There were no postprocedural complications. Normal oral intake was noted on postprocedural day 1. There was no evidence of stridor or respiratory distress. Seven days after the procedure, re-epithelialization was complete in the buccal incisions and nearly completed in the laryngeal incisions. CONCLUSION: The photonic band-gap fiber assembly produced reliable results in cutting with functional characteristics representing an improvement over current technology. The device shows promise as an effective tool for minimally invasive procedures that are amenable to use of the CO2 laser.  相似文献   
993.
Dave SP  Polak M  Casiano RR 《The Laryngoscope》2005,115(9):1641-1645
OBJECTIVES/HYPOTHESIS: To validate a previously reported in vitro tissue model for microdebrider comparison and determine which microdebrider, tissue type, blade type, and suction strength is most efficient. Specifically, the goal of the secondary analysis is to expand on the results of the preliminary analysis by increasing the sample size, and introduce an aspiration efficiency score (AES) to facilitate microdebrider comparison. STUDY DESIGN: Prospective randomized comparison. METHODS: A prospective randomized comparison of the Diego Powered Dissector and XPS 3000 Powered ENT System was conducted using a soft tissue and a firm tissue model. In addition to evaluating tissue aspiration with straight and angled blades, clogging rates and clearance times were measured. Both standard wall suction and liposuction were used. Basic statistical analysis, a one-way analysis of variance, and a post hoc Student's t test were performed to compare outcomes. RESULTS: With standard wall suction, the microdebriders were equivalent for the overall microdebrider comparison. For the 'head to head' comparison with standard wall suction, the devices were also equivalent when using the straight blades, but the XPS 3000 aspirated more tissue when using the angled blades. With liposuction, the XPS 3000 and liposuction independently aspirated more tissue but clogged more often compared with the Diego PD and regular suction. The aspiration efficiency of soft tissue (oysters) and straight blades was superior compared with firm tissue (scallops) and angled blades. For the 'head to head' comparison with liposuction, the XPS 3000 aspirated more tissue regardless of tissue type, but the Diego PD clogged less with firm tissue (scallops). Overall, the AES favored the XPS 3000, soft tissue (oysters), straight blades, and liposuction. CONCLUSION: Our tissue model represents a reliable and reproducible means of microdebrider comparison. Statistically significant differences between the Diego PD and XPS 3000, as well as between tissue types, blade types, and suction strengths, are reported. Using these results, microdebrider manufacturers can adopt similar tissue models, expand on the current AES, and include other commercially available microdebrider devices to test and report product performance to the consumer. Perhaps an optimal open to closed ratio or liposuction pressure can be determined that yields the greatest tissue aspiration with the fewest number of clogs.  相似文献   
994.
OBJECTIVES/HYPOTHESIS: To develop a technique for computer enhanced robotic transoral supraglottic partial laryngectomy in the canine model. STUDY DESIGN: Surgical procedure on the larynx in a canine model with a commercially available surgical robot. METHODS: With use of the da Vinci Surgical Robot (Intuitive Surgical, Inc., Sunnyvale, CA), the supraglottic partial laryngectomy was performed on a mongrel dog that had been orotracheally intubated using general anesthesia. The videoscope and the 8 mm end-effectors of the robotic system were introduced through three ports, transorally. The surgical procedure was performed remotely from the robotic system console. The procedure was documented with still and video photography. RESULTS: Supraglottic partial laryngectomy was successfully performed using the da Vinci Surgical Robot, with 8 mm instrumentation. The robotic system allowed for celerity and accuracy secondary to findings specific to the surgical approach, including excellent hemostasis, superb visualization of the operative field with expeditious identification of laryngeal submucosal soft tissue and skeletal landmarks, and multiplanar transection of tissues. In addition, the use of the robotic system also was found to have technical advantages inherent in robotic surgery, including the use of "wristed" instrumentation, tremor abolition, motion scaling, and three-dimensional vision. CONCLUSIONS: The da Vinci Surgical Robot allowed for successful robotic transoral supraglottic partial laryngectomy in the canine model.  相似文献   
995.
Malignant myoepithelioma is a rare salivary gland neoplasm that can arise either de novo or within a pre-existing pleomorphic adenoma. We report a case of malignant myoepithelioma arising from a pleomorphic adenoma of the soft palate. A 70-year-old woman presented in our department with a very large tumor of the soft palate. The patient had a history of a pleomorphic adenoma at the same location that was surgically removed 2 years ago. A second operation, with intraoral excision of the tumor was performed. Histological examination of the recurrence revealed a malignant spindle cell neoplasm with an infiltrative growth pattern and a high mitotic rate. Immunohistochemical investigation confirmed the diagnosis of a low-grade carcinoma of myoepithelial origin with free surgical margins. The patient remains free of disease for more than twelve months after the end of treatment.  相似文献   
996.
Soft palate implants: a new option for treating habitual snoring   总被引:1,自引:0,他引:1  
One hundred six patients with proven habitual snoring were each treated with three implants consisting of a cylindrical-shaped segment of braided polyester filaments (18 mm in length with an outer diameter of 1.5 mm) in the soft palate. The implants, pre-loaded in a single-use delivery tool, were inserted into the soft palate under local anesthesia. Along with the initial examination, follow-up exams were done after the treatment to test the safety and efficacy of the procedure. Snoring post treatment was reported as no snoring or slight/occasional in the majority of the cases after treatment. The results indicate there were no serious adverse events reported. The most frequent minor adverse events were partial extrusions in which the patient often presented a minor foreign body sensation along with mild transient pain. This data has demonstrated the procedure as a minimally invasive, relatively painless, simple procedure that has been shown to be safe and effective.  相似文献   
997.
The occurrence of granular cell tumor (GCT) in penile tissue is very rare, with only 9 examples reported to date in the English-language literature. Herein, we describe the clinicopathologic and immunohistochemical findings in 9 additional cases. The patients ranged in age from 20 to 60 years (mean, 42 years; median, 40 years) at time of diagnosis. All penile tumors were solitary and arose in the dermis of the penile shaft (n=4), prepuce (n=3), and corona (n=2). A patient had a history of multiple cutaneous GCTs. Duration of symptoms before surgery ranged from 5 days to 2 years with the presence of an asymptomatic nodule representing the most common tumor-related complaint (n=8). The lesions ranged in size from 0.6 to 2.5 cm (mean, 1.5 cm; median, 1.5 cm). Microscopically, the tumors were moderate to highly cellular and were composed of oval to polygonal-shaped cells with abundant coarsely granular eosinophilic cytoplasm. Tumor cells grew in infiltrating nests, cords, and trabeculae and showed neural (n=2) and vessel wall (n=1) invasion or formed a relatively well-marginated solid nodule. Bland cytological features with only rare cells showing nucleomegaly (n=7) or spindling (n=3) were exhibited by 8 tumors. A tumor demonstrated diffuse nuclear atypia and was classified as "atypical." Mitotic activity ranged from 0 to 8 mitoses (mean, 1.4 mitoses) per 50 high-powered fields with no atypical division figures identified. All tumors tested showed moderate to strong immunohistochemical expression of S100 protein (n=6) and low-affinity nerve growth factor receptor (n=5), which was useful for detecting small deposits of tumor and helpful in evaluating surgical margins. Focal tumor cell immunoreactivity was observed for calretinin (4/6 cases) and glial fibrillary acidic protein (1/6 cases). All patients underwent simple (local) excision of their tumor. Complete follow-up data (mean, 21 years; interval range, 0.5-28 years) were available for 6 patients. No patient experienced recurrence or metastatic spread of tumor although surgical margins were microscopically involved by tumor in 5 cases. Benign GCT involving superficial soft tissue of the penis can be adequately managed by a simple excision. Patients with microscopically involved surgical margins can be clinically followed without immediate additional surgery.  相似文献   
998.
BACKGROUND: Endoscopic ultrasound-guided fine-needle aspiration biopsy (EUS FNA) is a relatively new imaging modality that has been reported to be useful for mediastinal nodal staging of lung cancer and for the evaluation of mediastinal adenopathy of unknown cause. However, the technique is not commonly used in Australia. METHODS: A retrospective review of all patients who had mediastinal EUS FNA was undertaken. Of a total of 787 patients who had undergone endoscopic ultrasound (EUS) studies from November 1999 to March 2004, 27 patients were identified to have had mediastinal EUS FNA. Details were recorded including study indication, history of malignancy, source of referral, prior attempts for tissue diagnosis, EUS and EUS FNA findings, complications, surgical pathology if available and clinical outcome after diagnosis. RESULTS: Mediastinal EUS FNA was performed on an outpatient basis and no complications were recorded. Diagnostic material was obtained from all patients with a mean number of three passes. Nodal stations sampled included left paratracheal, subcarinal, aortopulmonary window and inferior mediastinum. Indications for the studies included mediastinal adenopathy of uncertain cause (17), lung cancer staging (7) and gastrointestinal cancer staging (3). EUS FNA confirmed malignancy in 16/27 patients, sarcoidosis in three patients, tuberculosis in one patient and seven patients were deemed to have reactive adenopathy. Primary cytopathological diagnosis of malignancy was determined by EUS FNA in nine patients. CONCLUSIONS: EUS FNA is a safe, efficient and effective modality for mediastinal staging of lung cancer and for the diagnosis of mediastinal adenopathy of uncertain origin. EUS FNA has the potential to significantly impact on patient management, avoiding more invasive procedures as well as unnecessary operations.  相似文献   
999.
Melorheostosis of the hand is rare. We report a 7-year-old girl who presented with a contracture of the left hand. Diagnosis was made by conventional radiography and bone scintigraphy. MRI proved to be a very useful tool to visualize the soft-tissue changes. This is especially important when surgical repair is considered.  相似文献   
1000.
BACKGROUND AND AIM: The biliary tract has been referred to as the "Achilles heel" of liver transplantation. The aim of this study was to document the frequency, clinical presentation and management of biliary complications after liver transplantation in the King Faisal Specialist Hospital and Research Center (KFSH&RC), Riyadh, Saudi Arabia. METHODS: The liver transplant clinic at KFSH&RC has registered and followed 220 patients (150 male and 70 female patients; age 40.6 +/- 18.6 years; pediatric 33, adult 187) during the period from 1987 to June 2003. A total of 235 transplants were carried out on these patients. Cadaveric liver transplants had been carried out on 202 patients, non-heart beating liver transplant in three patients, live donor liver transplants in 11 and split transplant in four. Biliary reconstruction was duct-to-duct anastomosis in 147 patients and Roux-en-Y in 73. Biliary complications were suspected on clinical and biochemical parameters and confirmed using imaging techniques. RESULTS: Forty patients (18.2%) developed 53 biliary complications. These included bile leak in 16, strictures in 25, calculi in eight, and sphincter of Oddi dysfunction and possible recurrence of primary sclerosing cholangitis in the donor duct in two patients each. Bile leaks were observed in the early postoperative period (median period 30 days, range 1-150 days, 95% confidence interval [CI] 8-51). Leakage occurred at the anastomotic site in 13 patients. Patients presented with bilious drainage (n = 6), abdominal pain at T-tube removal (n = 3), fever (n = 2), sepsis (n = 1), dyspnea (n = 1) and abnormal liver tests (n = 3). Eleven patients had intra-abdominal bilious collections. Two patients were treated conservatively, eight patients had ultrasound-guided aspiration of biloma, five had biliary stenting at endoscopic retrograde cholangiopancreatography and two patients needed surgery. There were four deaths, two of which were related to bile leak, one patient was left with permanent external biliary drainage and four patients had biliary strictures in the follow-up period. Biliary strictures occurred at a median period of 360 days (range 4-2900 days; 95% CI 50-670) after the transplant. Hepatic artery thrombosis caused biliary strictures in three, while 21 strictures were localized to the anastomotic site. Biliary strictures presented with elevated liver tests in five patients, progressive cholestasis in five, cholangitis (with septicemia in five) in 11, abdominal pain in two and acute pancreatitis in three patients. Repeat sessions of endoscopic or percutaneous dilatation and stenting (mean sessions 4.4/patient, range 3-7) were attempted in 20 patients to relieve strictures, with success in only nine patients. Seven patients had surgery. Four patients with biliary strictures died. Biliary calculi developed late in the follow-up period and had the appearance of biliary casts in five and sludge in three patients. Eleven (27.5%) patients with biliary disease died compared with 35 (19.4%) patients without biliary disease. CONCLUSIONS: Biliary complications occurred in 18.2% of patients after liver transplantation and included biliary leak and biliary strictures with or without calculi. Management involved a combination of endoscopic, radiologic and operative procedures. Biliary complications caused considerable morbidity and mortality in liver transplant patients.  相似文献   
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