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71.
Retrorectal or presacral tumors are rare lesions located in the presacral area and considered as being derived from multiple embryological remnants. These tumors are classified as congenital, neurogenic, osseous, inflammatory, or miscellaneous. The most common among these are congenital benign lesions that present with non-specific symptoms, such as lower back pain and change in bowel habit. Although congenital and developmental tumors occur in younger patients, the median age of presentation is reported to be 45 years. Magnetic resonance imaging plays a crucial role in treatment management through accurate diagnosis of the lesion, the evaluation of invasion to adjacent structures, and the decision of appropriate surgical approach. The usefulness of preoperative biopsy is still debated; currently, it is only indicated for solid or heterogeneous tumors if it will alter the treatment management. Surgical resection with clear margins is considered the optimal treatment; described approaches are transabdominal, perineal, combined abdominoperineal, and minimally invasive. Benign retrorectal tumors have favorable long-term outcomes with a low incidence of recurrence, whereas malignant tumors have a potential for distant organ metastasis in addition to local recurrence.  相似文献   
72.
Social insurance administrative officers’ decision-making skills influence their efficiency at work and their general well-being. At work their tasks are characterised by complexity and a need for order and accountability. Moreover, cases should usually be handled and finalised within the imposed time frames. We investigated skills related to decision-making success among social insurance officers. In total, 118 administrative officers at the Swedish Social Insurance Agency (66% response rate) responded to questions on scales and measures relating to cognitive-rational, socio-emotional and time approach features of decision-making skill. In addition, they responded to questions on three scales pertaining to outcomes of everyday decisions in terms of subjective everyday difficulties, tendencies to burnout and depressive symptoms. The results showed that cognitive-rational competence was associated with lower reports of subjective everyday difficulties and depressive symptoms and thereby contributed to the explained variance in decision outcomes. Furthermore, socio-emotional and time approach features of decision-making skills contributed to the explanation for subjective everyday difficulties, tendencies to burnout and depressive symptoms. The results corroborate the basic assumption and usefulness of a broad approach in the definition and assessment of decision-making skills in human service professions in general, and of administrative officers in social insurance agencies in particular. Recommendations for future research and the implications of the results are discussed.  相似文献   
73.
Between 1953 and 1989 eighty cases of non-traumatic brain abscess were treated in our department. We have re-examined the clinical and neuroradiological features of this pathological process and present our therapeutic approach and results. We believe that the optimal treatment for brain abscess consists of surgical removal.The prognosis for these lesions has undergone a marked improvement over the last two decades in response to neuroradiological, microbiological and surgical advances. The most influential prognostic factor seems to be preoperative clinical status.  相似文献   
74.
目的:探讨岩斜区肿瘤外科治疗手术入路选择。方法:回顾性分析我院自1997年至2000年6月显微外科手术治疗的17例岩斜区肿瘤。12例肿瘤直径大于4cm。采用6种手术入路:颞下-小脑幕;天幕上下联合;颞下-乙状窦前;枕下乳突后;枕下远外侧;额眶颧入路。结果:肿瘤全切除12例(71%),术后恢复良好者11例(65%),术后新增颅神经损害6例(35%)。结论:选择和掌握适合的颅底手术入路,采用显微外科技术入路,采用显微外科技术切除岩斜区肿瘤可取得满意效果。  相似文献   
75.
76.
A new type of ultra-short acting -blocker which might prove advantageous in treating acute arrhythmias was designed, synthesized and investigated. Based on the soft drug inactive metabolite approach, the inactive phenylacetic acid metabolite of both metoprolol and atenolol was reactivated by esterification with sulfur-containing aliphatic alcohols. Since the sulfur-containing moieties are labile to the ubiquitous esterases, the new compounds should be inactivated by a one step enzymatic cleavage back to the inactive phenylacetic acid derivative. Pharmacological and pharmacokinetic profiles of the new compounds were evaluated in rats and rabbits. Isoproterenol-induced tachycardia was inhibited with short-term infusion of each compound. This tachycardia blocking effect rapidly disappeared upon termination of infusion, while -blocking activity was 2–4-fold longer after comparable doses of the short-acting -blocker, esmolol. The rapid recovery from the -receptor blockade is believed due to fast hydrolysis of the soft drugs in the body. This is supported from in vitro results showing the tl/2 of esmolol is about 10-fold longer than the new soft drugs in rat, rabbit, dog and human blood. Hydrolysis studies in phosphate buffered solutions indicated that the esters are labile to base-catalyzed hydrolysis. However, the relative t1/2 values measured in biological media compared to phosphate buffered solution clearly support rapid enzymatic cleavage of the soft drugs. Interestingly, one of the soft -blockers, the sulfonyl ester derivative, showed a unique property of exhibiting good -receptor blocking activity without significant hypotensive action.  相似文献   
77.
目的:为获得经岩骨入路颈静脉孔区手术相关的国人解剖学参数,指导临床实践。方法:通过解剖观测30 侧国人尸头,对有关岩骨入路数据进行测量。结果:鼓环~颈静脉球顶距离为(4.84±3.84)m m ,鼓环~面神经距离为(2.71±0.81)m m ,后半规管~颈静脉球顶距离为(4.99±4.41)m m ,膝状神经节~颈内动脉膝部距离为(7.71±1.47)m m ,面神经垂直部~颈静脉球距离为(5.67±2.24)m m 。结论:术中如能注意相关解剖学参数,可提高治愈率,减少并发症和死亡率  相似文献   
78.
Summary  The incidence of high cervical disc lesions is extremely rare, and the mechanism of their development is unclear. We report these three cases, and discuss the possible mechanisms. We also describe surgical strategies for these lesions.  The first and second cases were an 82-year-old male and an 84-year-old male with retro-odontoid disc hernia. The third was an 83-year-old female with a herniated disc at C2/C3. To investigate Aetiological mechanisms of these lesions, we examined the findings on cervical images in extension and flexion, and compared the results in a younger than 80-year-old group and an older than 80-year-old group.  The patients underwent surgery via a posterolateral intradural approach. Wide laminectomy and incision of the dentate ligaments enabled access to the ventral space of the upper cervical spinal canal and sufficient decompression. All patients became ambulatory postoperatively without special fixation of the cervical spine. In the younger group, the level mostly loaded during cervical movement was C5/6, however, the levels in the older group were C2/3 and C3/4.  In elderly patients, less mobilization of the middle and/or lower cervical spine due to spondylotic change causes overloading at higher levels resulting in high cervical disc lesions. Retro-odontoid disc lesions can be caused by a herniated disc at C2/C3, which migrates upward. Regarding surgical strategy, the posterolateral intradural approach is less invasive and more advantageous for these lesions.  相似文献   
79.
Rajaraman V  Schulder M 《Surgical neurology》1999,52(6):70-8; discussion 598-9
BACKGROUNDKnowledge of the magnetic resonance imaging (MRI) appearance of the pituitary fossa following transsphenoidal resection of a pituitary adenoma, in the early and late postoperative period, is important for detecting complications and for assessing extent of tumor excision. Few prospective studies have addressed this issue.METHODSFourteen patients with pituitary macroadenomas were prospectively studied with MRI. Maximal tumor resection was accomplished in each patient, and the postoperative histological diagnoses included non-secreting adenoma in 11 patients, prolactinoma in 2 and necrosis in one. Early postoperative scans were obtained within 14 days after surgery, and late studies between 3 and 4 months, in all patients. Four patients also had delayed scans between 8 months and a year. The maximum coronal dimension (MCTD) of the sellar and suprasellar contents was measured on T1-weighted contrast enhanced scans.RESULTSAll patients had normal or improved visual examinations and normal or improved hormonal function postoperatively. The preoperative MCTD ranged from 11 mm to 59 mm in height (mean 30.3 mm). There was little change in MCTD on the early postoperative MRI scans (range 7–49 mm, mean 23.5 mm). However, in all patients the MCTD decreased in height by 4 months (range 2–35 mm, mean 12.7 mm). This change represented a 58% mean reduction in size compared to the preoperative measurements.CONCLUSIONSWe conclude that the appearance of the sellar contents on early postoperative MRI may appear remarkably similar to that seen before surgery, even after technically adequate resection. The postoperative mass may represent a combination of residual tumor, edema, postoperative hemorrhage and hemostatic material. Routine follow-up MRI after transsphenoidal resection of pituitary tumors may be delayed until at least 4 months after surgery in patients who are clinically stable.  相似文献   
80.
This report concerns one case of a sphenoid sinus mucocele occurring 17 years after transsphenoidal surgery for acromegaly. In 1979, a 51-year-old man was successfully operated by the transnasal transsphenoidal approach for a growth hormone (GH) adenoma 1 cm in diameter. In 1996, the patient was hospitalized for headaches and diplopia. He presented a loss of right visual acuity with paralysis of the right oculomotor nerve. The basal GH level was normal with a satisfactory decrease after oral glucose ingestion. Pituitary sellar radiography showed a disappearance of the posterior clinoid while magnetic resonance imaging revealed the existence of a bilocular, circular, homogeneous lesion of the sphenoid sinus 3 cm in diameter with a posterior and lateral extension. The diagnosis of mucocele was confirmed by surgical treatment, allowing drainage of the mucocele through a transsphenoidal approach. The drained material was composed of sinus epithelium containing many polynuclear and resorptive cells. Postoperatively, the symptoms decreased dramatically, leading to full recovery of visual function and disappearance of the headaches. Apart from the tumor recurrence, the mucocele of the sphenoid sinus can be evoked as a possible long term complication of transsphenoidal sugery for pituitary adenoma. Received: 2 June 1998 / Accepted: 23 February 1999  相似文献   
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