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91.
92.
The irregular shape or contour of the patient’s surface in the treatment field can alter the dose distribution resulting in non-uniformity of dose in the treatment volume. Missing tissue compensators have been most commonly used to improve this non-uniformity, especially in head & neck, breast, lung and supraclavicular regions. Two or three dimensional compensators have been typically designed to make the dose uniform at a specific depth. This compensation shifts the dose distribution within the treatment volume so that some structures may be under or over compensated. This study will examine how various sites in head and neck cases are affected by compensators. We have also analyzed the uncertainty in compensated dose due to the daily variations in patient repositioning. Computer isodose plans using Cobalt-60 gamma rays and 6 and 18 MV x-rays were generated using coronal contours. Results show that the dose uniformity is improved for the treatment sites, especially for the thinner sites, like the larynx and the anterior cervical neck nodes. Finally, patient movement or positioning errors of ±1.0 cm will cause a change in dose distribution. 相似文献
93.
Many patients present with lateral neck lumps due to benign or malignant conditions, and they may be difficult to differentiate clinically. It is detrimental to perform an open neck biopsy on a patient with a cancer originating from the head and neck region (upper aerodigestive tract or skin) prior to definitive treatment. The biopsy interferes with the assessment and management of the neck, increasing morbidity. It may also decrease curability and perhaps induce fungation. A protocol to avoid the need for an open biopsy, using fine needle aspiration cytology and a thorough examination of the upper aerodigestive tract is recommended. The authors also recommend combined radical radiotherapy and surgery for the patient who has had an open biopsy. A thoughtless biopsy is both needless and harmful. 相似文献
94.
目的 分析模拟教学联合心理暗示在耳鼻咽喉头颈外科住培模拟教学中的应用价值。方法 选取于清华大学附属北京清华长庚医院耳鼻咽喉头颈外科进行住培的36例住培医师,按不同教学模式将其分为研究组(n=20,模拟教学联合心理暗示)与对照组(n=16,传统教学)。比较两组住培医师考核成绩、综合能力、教学效果及教学满意度。采用SPSS 22.0进行t检验和卡方检验。结果 带教后,两组住培医师理论考试、技能考核成绩、学习兴趣、自学能力、沟通能力及临床诊疗水平评分均较带教前上升,且研究组上升程度明显优于对照组(P<0.05)。研究组兴趣程度、难易程度、可参与性、掌握程度评分均明显高于对照组(P<0.05)。研究组住培医师教学总满意度为95.00%,明显高于对照组的68.75%(P<0.05)。结论 模拟教学联合心理暗示在耳鼻咽喉头颈外科住培教学中可提高学员理论知识、技能操作水平、综合能力及教学水平,且学员对该教学方法满意度高。 相似文献
95.
Bexander CS Mellor R Hodges PW 《Experimental brain research. Experimentelle Hirnforschung. Expérimentation cérébrale》2005,167(3):422-432
Control of the neck muscles is coordinated with the sensory organs of vision, hearing and balance. For instance, activity
of splenius capitis (SC) is modified with gaze shift. This interaction between eye movement and neck muscle activity is likely
to influence the control of neck movement. The aim of this study was to investigate the effect of eye position on neck muscle
activity during cervical rotation. In eleven subjects we recorded electromyographic activity (EMG) of muscles that rotate
the neck to the right [right obliquus capitis inferior (OI), multifides (MF), and SC, and left sternocleidomastoid (SCM)]
with intramuscular or surface electrodes. In sitting, subjects rotated the neck in each direction to specific points in range
that were held statically with gaze either fixed to a guide (at three different positions) that moved with the head to maintain
a constant intra-orbit eye position or to a panel in front of the subject. Although right SC and left SCM EMG increased with
rotation to the right, contrary to anatomical texts, OI EMG increased with both directions and MF EMG did not change from
the activity recorded at rest. During neck rotation SCM and MF EMG was less when the eyes were maintained with a constant
intra-orbit position that was opposite to the direction of rotation compared to trials in which the eyes were maintained in
the same direction as the head movement. The inter-relationship between eye position and neck muscle activity may affect the
control of neck posture and movement. 相似文献
96.
Hausfater P Fillet AM Rozenberg F Arthaud M Trystram D Huraux JM Lebon P Riou B 《Journal of medical virology》2004,73(1):137-146
Aseptic meningitis is a frequent diagnosis in emergency departments. Nevertheless, viral investigations are not carried out currently and the viral etiology in adult population has not been studied extensively. We conducted a prospective study including all consecutive patients undergoing lumbar puncture during a 15 months period in an adult emergency department. Bloody and purulent cerebrospinal fluid (CSF) were excluded. The main tests undertaken were: CSF genomic amplification by the polymerase chain reaction (PCR) for neurotropic viruses and serum and CSF interferon-alpha (IFN-alpha) measurements. Among 194 patients included, 45 had and 149 did not have aseptic meningitis. Of 45 patients with aseptic meningitis, 10 had alternative non-virological final diagnosis, and 35/45 were presumed to have neurological disorders of viral origin. Patients (27/35) completed virological analysis: 21/27 (78%) had either positive viral PCR (enterovirus: 8 patients, Varicella zoster virus (VZV): 5, Epstein-Barr virus (EBV): 2, herpes simplex virus (HSV): 1, human herpes virus 6: 1) or only raised serum or CSF IFN-alpha (4 patients). Overall, 59% of patients with a positive viral PCR had either CSF or serum raised IFN-alpha. Twentyone patients without meningitis had either positive viral PCR (enterovirus: 3 patients) or only high serum IFN-alpha level (18 patients). In the setting of aseptic meningitis diagnosed in an adult emergency department, viruses are the most common agents encountered, with enterovirus and VZV as the two main etiological agents. Current CSF viral genome amplification and IFN-alpha measurement are informative and could be useful to confirm the viral origin of various neurological disorders, although the sensitivity and specificity of IFN-alpha measurement for the diagnosis of viral infection need further confirmation. 相似文献
97.
M. John Hicks Victor A. Saldivar Murali M. Chintagumpala Marc E. Horowitz Linda D. Cooley James P. Barrish Edith P. Hawkins Claire Langston 《Ultrastructural pathology》1995,19(5):395-400
Malignant melanoma of soft parts (MMSP) was originally described as a distinct entity by Enzinger in 1965 and was termed “clear cell sarcoma of tendons and aponeuroses” because of its association with tenosynovial structures. It has been shown immunophenotypically and ultrastructurally that this tumor is derived from neuroectoderm and shares a number of features with cutaneous melanoma. Over 95% of MMSPs present in the extremities, with the head and neck region (1.9%) being an unusual site. This study presents an additional case of MMSP of the head and neck region involving the posterior cervical region in a 15-year-old Hispanic male and reviews the literature on MMSP. Ultrastructural examination showed rudimentary cell attachments, smooth cell membranes, discontinuous basal lamina, scanty glycogen, and occasional premelanosomes in some tumor cells. Cytogenetic analysis showed a reciprocal translocation between the long arms of chromosomes 12 and 22 [t(12:22)(q13;q12.2)], characteristic for MMSP and not seen in cutaneous melanoma. Survival in MMSP has been correlated with tumor size, tumor necrosis, and ploidy status. Overall reported clinical outcome for this tumor is as follows: died of disease, 45%; alive with disease, 23%; no evidence of disease, 30%; and died of other causes, 2%. MMSP represents a distinct entity with a characteristic ultrastructural appearance and a tumor defining cytogenetic translocation. 相似文献
98.
An unusual case study of a desmoplastic small round cell tumor presenting as a 3.5-cm, firm, supraclavicular neck mass and diagnosed by fine-needle aspirate biopsy in a 16-yr-old male is reported. Clinical, cytologic, and immunocytochemical findings are described. Histologic, immunohistochemical, and genetic features are discussed. Desmoplastic small round cell tumor should be considered in the differential diagnosis of small round cell tumors of any site; the importance of ancillary studies in arriving at the correct diagnosis is emphasized. 相似文献
99.
带监测皮岛腓骨移植治疗股骨颈骨折 总被引:1,自引:0,他引:1
目的:探讨监测皮岛腓骨移植治疗股骨颈骨折的临床价值。方法:用带监测皮岛的腓骨移植结合AO空心钉内固定治疗11例中青年股骨颈骨折患者。结果:11例中1例监测皮岛于术后监测过程中准确地提示移植腓骨血管危象,及时手术探查处理,复通血供。11例监测皮岛全部成活,随访1~3年,股骨颈骨折端骨愈合,股骨头无坏死。结论:带监测皮岛吻合血管的腓骨移植治疗股骨颈骨折疗效可靠,监测皮岛是腓骨移植术后血供监测的可靠方法。 相似文献
100.
目的探讨距骨颈骨折治疗方案的选择以及疗效相关因素分析。方法距骨颈骨折15例,男13例,女2例。年龄16~63岁,平均40.5岁,合并腰椎、髋臼、跟骨、外踝骨折各1例。开放骨折2例。陈旧性骨折2例(〉1个月)。按Hawkins骨折分类:Ⅰ型3例、Ⅱ型9例、Ⅲ型3例。Ⅰ型骨折采用膝下管型石膏固定,其中1例复诊中因移位行切开复位松质骨螺钉固定。Ⅱ型骨折均行切开复位,克氏针或松质骨螺钉固定。Ⅲ型骨折1例开放性骨折,急诊行清创缝合,手法+撬拔复位,脱位整复。一周后在C臂机引导下,采用二枚直径4.0mm中空螺钉由后向前固定距骨颈,1例急诊手术切开复位,克氏针内固定。结果本组13例获得随访,时间4~24个月,平均12.3个月。13例中发生距骨体缺血性坏死5例,其中Ⅱ型骨折4例,Ⅲ型骨折1例。另2例未统计在内。1例外院病例术后并发伤口感染长期不愈,行小腿截肢术。1例患者拒绝手术治疗。按Hawkims疗效标准,优4例,良4例,可3例,差2例,优良率69%。结论对无移位的距骨颈骨折,行膝下管型石膏固定6~12周,并定期拍片复查,距骨颈骨折脱位应急诊复位和可靠的内固定。以2枚拉力螺钉内固定为宜,尽量减少并发症。对距骨体缺血性坏死,或创伤性关节炎,则根据患者的实际情况采取相应治疗措施。 相似文献