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61.
Vestibular schwannomas have been traditionally managed with microsurgical removal and in recent years, stereotactic radiotherapy. However, there is a group of patients in whom a conservative management approach might represent a desirable alternative. The aim of this study was to determine the natural history and outcome following the conservative management of 72 patients with unilateral vestibular schwannomas. This is a prospective cohort review of a previously published group of patients [Clin. Otolaryngol. (2000) 25, 28-39] with unilateral vestibular schwannoma that were initially analysed at our institution in 1998 [Walsh R.M., Bath A.P., Bance M.L. et al., Clin. Otolaryngol. (2000) 25, 28]. The mean duration of follow-up was 80 months (range 52-242 months). All the patients in the study underwent serial magnetic resonance imaging (MRI) for assessment of tumour growth. Patients were deemed to have failed conservative management if there was evidence of rapid radiological tumour growth and/or increasing signs and symptoms, which necessitated active intervention. The mean tumour growth rate for the entire group at the second review was 1 mm/year (range -0.84-9.65 mm/year). The mean growth rate for cerebellopontine angle tumours (1.3 mm/year) was significantly greater than that of internal auditory canal (IAC) tumours (0 mm/year) (P = 0.005). The majority of tumours (87.14%) grew <2 mm/year. There was significant tumour growth seen in 38.9%, no or insignificant growth in 41.7%, and negative growth in 19.4%. Twenty-three patients (32%) failed conservative management at the second review. There was no difference in the outcome of these failed patients in comparison with patients who underwent primary treatment without a period of conservative management. The mean growth rate of tumours in patients that failed conservative management (3.1 mm/year) was significantly greater than that in patients who did not fail (0.2 mm/year) (P < 0.001). No factors predictive of tumour growth or failure of conservative management were identified. Hearing deterioration with pure tone averages (0.5, 1, 2, 3 kHz) and speech discrimination scores occurred irrespective of tumour growth. This prospective study further emphasizes the role of conservative management in selected cases of vestibular schwannomas. Tumours in this study confined to the IAC typically demonstrated minimal or no growth on serial MRI scanning. Regular follow-up with interval scanning is mandatory in all patients.  相似文献   
62.
Skeletal echinococcosis is a relatively rare entity and that of the rib is exceptional. Less than 50 cases of costal echinococcosis have been reported in the literature so far. Accurate pre-operative diagnosis aids in appropriate management and helps to eradicate the disease. This also prevents the dissemination of parasite and further complications. We report a case of echinococcosis of the rib with epidural extension in a young adult who presented with paraparesis and back pain. His laboratory investigations were within normal limits. Plain radiographs of the dorsal spine, CT scan of thorax and MRI of dorsal spine were performed. The imaging features were suggestive of echinococcosis involving the rib with epidural extension. The cyst was completely resected. Histopathology of the resected specimen confirmed the diagnosis of echinococcosis.  相似文献   
63.
Leiomyomas of the renal parenchyma and of the capsule are rare. These tumours are normally small asymptomatic and often detected incidentally. Large renal leiomyomas can present with pain or as an abdominal mass, but they are rare. The imaging features of these tumours have been poorly described in the literature. A radiological distinction from other renal neoplasms is often difficult to make owing to the similarity of imaging findings. We report two patients with renal leiomyomas who presented with pain and an abdominal mass. Both patients underwent nephrectomy and histological evaluation confirmed the diagnosis of leiomyoma.  相似文献   
64.
The length and quality of life of patients with localized pancreatic cancer will be maximized by accurate preoperative assessment of resectability, a standardized technique of tumor resection, and the routine use of protocol-based adjuvant or neoadjuvant therapy. Continued efforts to enroll patients with localized and advanced pancreatic cancer into well-designed clinical trials should remain a high priority for oncologists across all disciplines. At present, preoperative therapy remains investigational but has a sound clinical basis and remains a reasonable alternative to up front surgery. Future clinical trials for resectable pancreatic cancer will lead to progress only if the principles of multidisciplinary cancer care and quality assurance are incorporated into their design and conduct.  相似文献   
65.
Unusual functioning endocrine tumors   总被引:2,自引:0,他引:2  
Opinion statement Endocrine surgeons should maintain a high index of suspicion when patients are diagnosed with clinical signs or symptoms of parathyroid carcinoma. Although rare, the best chance for cure of these patients is at the time of the initial operation. Surgical resection of recurrent disease can provide effective palliation and can sometimes be assisted using gamma-probe directed dissection of sestamibi-labeled tumor tissue. Treatment of hyper-parathyroidism in the setting of multiple endocrine neoplasia type 1 (MEN-1), particularly in the reoperative setting, can be aided by using the rapid intraoperative parathyroid hormone assay to judge the adequacy of parathyroid debulking. In addition, in selected cases, the gamma probe can assist in identifying the location of ectopic or autografted sestamibi-labeled parathyroid tissue. Patients with incidental adrenal masses rarely require fine needle aspiration to exclude metastatic cancer. Fine needle aspiration, if performed, should never precede hormone evaluation to exclude pheochromocytoma. Patients who are diagnosed with incidental adrenal masses in the setting of a prior or concurrent cancer diagnosis are equally likely to have a primary adrenal mass as they would be to have metastatic cancer in the adrenal gland. Pheochromocytomas occasionally develop in patients with MEN-1. In suspicious cases, molecular identification of an MEN-1 mutation can be used to confirm the diagnosis. Preoperative hormone evaluation of a patient with an adrenal incidentaloma should include evaluation for subclinical Cushing’s syndrome through an overnight 1-mg dexamethasone suppression test. Identification of this condition allows for safe peri- and postoperative steroid hormone replacement, with very slow withdrawal of exogenous steroids to allow the opposite adrenal gland to recover and avoid postoperative Addisonian crisis. Paragangliomas are more commonly multifocal and malignant compared to pheochromocytomas. Evaluation of patients with paragangliomas should include radiographic staging for multifocality and metastatic disease, and postoperative hormone and radiographic follow-up evaluation should be performed. Consideration should be given to genetic testing for von Hippel-Lindau and succinate dehydrogenase mutations. Surgical treatment of rare functioning pancreatic and duodenal endocrine tumors, such as metastatic sporadic insulinoma and MEN-1-associated gastrinoma, can provide effective palliation. Surgical treatment should be integrated into a comprehensive treatment scheme that recognizes the natural history of the disease and incorporates appropriate adjunctive therapies and follow-up strategies.  相似文献   
66.
Cochlear implantation in maternal inherited diabetes and deafness syndrome   总被引:1,自引:0,他引:1  
We describe a rare case of a gradually progressive hearing loss in a patient with maternally inherited diabetes and deafness (MIDD) syndrome successfully rehabilitated with a cochlear implant. The possible aetiology of the hearing loss in these cases is discussed.  相似文献   
67.
OBJECTIVE: To evaluate bipolar scissors tonsillectomy by comparing it with traditional cold dissection tonsillectomy. The outcome measures used were: (1) intra-operative bleeding; (2) operative time; (3) post-operative pain; and (4) complication rates including reactionary and secondary hemorrhage. METHOD: A prospective, randomized multiunit study involving three teaching hospitals in Belfast. Fifty consecutive children aged 10-16 years undergoing tonsillectomy for recurrent or chronic tonsillitis, between March 2000 and September 2000 were recruited as a subgroup of 200 patients selected for this study. These children were analysed separately from the adults, in a pilot study for the above parameters. RESULTS: The mean age of the study population was 14.3 years. Sixty-eight percent of the children were girls. Median intra-operative blood loss was 6 ml for bipolar scissors tonsillectomy and 86 ml for cold dissection tonsillectomy (P<0.001). The median operative time was 10.5 min for bipolar scissors tonsillectomy compared to 14.5 min for the cold dissection method (P=0.001). There was no statistically significant difference in the pain scores between the two methods (P>0.05). The overall reactionary hemorrhage rate was 4% while the overall secondary hemorrhage rate was 14%. The hospital readmission rate was 4%. The reactionary and secondary hemorrhage rates were unaffected by the surgical method. CONCLUSIONS: This pilot study has shown that bipolar scissors tonsillectomy is a relatively safe technique in children aged 10-16 years with a similar morbidity to the cold dissection method. Its use is associated with a significant decrease in surgical time and blood loss compared to the cold dissection method. These advantages make it a favourable instrument for pediatric tonsillectomy especially in this age group.  相似文献   
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Binding to anionic phospholipid (PL) is essential for the biological function of factor VIII (FVIII). We have developed a method to study the level of PL binding of FVIII in a variety of therapeutic concentrates, using the BIACORETM system which utilizes the Surface Plasmon Resonance (SPR) phenomenon. A HPA sensor chip was employed on to which synthetic phospholipid unilamellar vesicles were adsorbed to form a 3:1 phosphatidylcholine: phosphatidylserine lipid monolayer. Using this surface the interaction of unlabelled FVIII in concentrates was observed from which direct kinetic data (kon, koff and KD values) were obtained in real-time. Marked differences in the binding to PL, as measured by KD values, between different products were observed. These fell into three categories: two recombinant FVIII products showed high affinities for PL with KD values around 0. 05-0.14 nM; four high-purity plasma derived products, two prepared by monoclonal antibody and two prepared by ion-exchange chromatography, had 6-8-fold lower affinities, and two intermediate-purity products had 34-60-fold lower affinities with KD values in the nM region. Measurements of kon and koff values for each product showed that the differences in the KD values expressed were primarily due to the differences in their respective kon values, although the recombinant products showed changes in the koff values. The study showed that the assessment of binding to PL by FVIII in concentrates was possible without prior purification and gave KD values in the range reported previously for other methods. The difference between the products requires further investigation but may be partly due to other proteins present, in particular the content and quality of von Willebrand factor which is known to affect PL binding of FVIII.  相似文献   
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