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101.
BACKGROUND: The incidence and patterns of nodal spread in previously irradiated N0 necks are not well defined. Therefore, the safety and efficacy of selective neck dissection (SND) in this patient population is not well established. In a previous report from our institution, SND in irradiated patients with recurrent disease at the primary site but clinically negative necks resulted in excellent tumor control in the neck. The objective of this study is to validate our initial observations in a larger sample of patients with longer follow-up. METHODS: A retrospective chart analysis of patients previously treated with primary radiation therapy or chemoradiotherapy for squamous cell carcinoma (SCC) of the head and neck between January 1997 and June 2003 was performed. Patients with recurrent or persistent disease at the primary site or a second primary head and neck SCC, with no clinical or radiologic disease in the neck, who underwent surgical salvage with resection of the primary site along with a site-specific SND were analyzed. Patients who remained disease free at the primary site were analyzed for regional control after SND. RESULTS: Sixty-nine patients underwent a total of 96 site-specific SNDs. The mean age was 64.1 years (range, 39-91 years). There was histologically positive nodal disease in 17 of 69 patients (25%), and 22 of 96 necks (23%). Fifty-three patients had at least a 12-month follow-up. The mean follow-up was 23.3 months (range, 1-96 months). Of the patients with 1-year of follow-up, six patients died from recurrence at the primary site, and nine died from distant metastasis. There were no cases of neck recurrence with the primary site controlled. All patients who had more than two positive nodes had recurrence either at the primary site or distant metastasis. CONCLUSIONS: Our results confirm that the patterns of lymphatic spread are not affected by radiation. We conclude that SND is oncologically safe in the management of the N0 irradiated neck and that the finding of more than two positive nodes predicts a poor outcome.  相似文献   
102.
To evaluate the effect of an abstract motivational incentive on top-down mechanisms of visual spatial attention, 10 subjects engaged in a target detection task and responded to targets preceded by spatially valid (predictive), invalid (misleading) or neutral central cues under three different incentive conditions: win money (WIN), lose money (LOSE), and neutral (neither gain nor lose). Activation in the posterior cingulate cortex was correlated with visual spatial expectancy, defined as the degree to which the valid cue benefited performance as evidenced by faster reaction times compared to non-directional cues. Winning and losing money enhanced this relationship via overlapping but independent limbic mechanisms. In addition, activity in the inferior parietal lobule was correlated with disengagement (the degree to which invalid cues diminished performance). This relationship was also enhanced by monetary incentives. Finally, incentive enhanced the relationship of activation in the visual cortex to visual spatial expectancy and disengagement for both types of incentive (WIN and LOSE). These results show that abstract incentives enhance neural processing within the attention network in a process- and valence-selective manner. They also show that different cognitive and motivational mechanisms may produce a common effect upon unimodal cortices in order to enhance processing to serve the current behavioral goal.  相似文献   
103.
Patients with lesions in posterior parietal cortex (PPC) are relatively unimpaired in voluntarily directing visual attention to different spatial locations, while many neuroimaging studies in healthy subjects suggest dorsal PPC involvement in this function. We used an offline repetitive transcranial magnetic stimulation (rTMS) protocol to study this issue further. Ten healthy participants performed a cue-target paradigm. Cues prompted covert orienting of spatial attention under voluntary control to either a left or right visual field position. Targets were flashed subsequently at the cued or uncued location, or bilaterally. Following rTMS over right dorsal PPC, (i) the benefit for target detection at cued versus uncued positions was preserved irrespective of cueing direction (left- or rightward), but (ii) leftward cueing was associated with a global impairment in target detection, at all target locations. This reveals that leftward orienting was still possible after right dorsal PPC stimulation, albeit at an increased overall cost for target detection. In addition, rTMS (iii) impaired left, but (iv) enhanced right target detection after rightward cueing. The finding of a global drop in target detection during leftward orienting with a spared, relative detection benefit at the cued (left) location (i-ii) suggests that right dorsal PPC plays a subsidiary rather than pivotal role in voluntary spatial orienting. This finding reconciles seemingly conflicting results from patients and neuroimaging studies. The finding of attentional inhibition and enhancement occurring contra- and ipsilaterally to the stimulation site (iii-iv) supports the view that spatial attention bias can be selectively modulated through rTMS, which has proven useful to transiently reduce visual hemispatial neglect.  相似文献   
104.
The present study examined the activity levels of the thoracic and lumbar extensor muscles during different extension exercise modalities in healthy individuals. Therefore, 14 subjects performed four different types of extension exercises in prone position: dynamic trunk extension, dynamic–static trunk extension, dynamic leg extension, and dynamic–static leg extension. Pre‐ and post‐exercise muscle functional magnetic resonance imaging scans from the latissimus dorsi, the thoracic and lumbar parts of the longissimus, iliocostalis, and multifidus were performed. Differences in water relaxation values (T2‐relaxation) before and after exercise were calculated (T2‐shift) as a measure of muscle activity and compared between extension modalities. Linear mixed‐model analysis revealed higher lumbar extensor activity during trunk extension compared with leg extension (T2‐shift of 5.01 ms and 3.55 ms, respectively) and during the dynamic–static exercise performance compared with the dynamic exercise performance (T2‐shift of 4.77 ms and 3.55 ms, respectively). No significant differences in the thoracic extensor activity between the exercises could be demonstrated. During all extension exercises, the latissimus dorsi was the least activated compared with the paraspinal muscles. While all extension exercises are equivalent effective to train the thoracic muscles, trunk extension exercises performed in a dynamic–static way are the most appropriate to enhance lumbar muscle strength.  相似文献   
105.
目的观察比较椎弓根器械复位固定后两种不同融合法PLF与PLIF对峡部裂型滑脱的疗效。方法Ⅱ度以内腰椎峡部裂型滑脱共47例,一组22例,椎弓根器械复位固定后行PLF(PLF组);另一组25例,椎弓根器械复位固定后行PLIF(PLIF组)。对两组的临床疗效(ODI评分)、X线影像学结果(包括:滑脱矫正、滑脱节段椎间隙高度改变、滑脱节段前突角改变及骨融合)及并发症进行对比观察。结果术后即刻X线影像学结果,包括:滑脱矫正、滑脱节段椎间盘高度、滑脱节段前突角,两组间无显著差异(P>0.05);术后2年随访时,滑脱矫正及滑脱节段椎间隙高度的维持上PLIF组优于PLF组(P<0.05),骨融合率及滑脱节段前突角两组间无显著差异(P>0.05),但两组间临床疗效(ODI评分)及并发症发生率无显著差异(P>0.05),内固定失败率PLF组高于PLIF组。结论椎弓根器械复位固定并PLF与PLIF都是治疗Ⅱ度以内腰椎峡部裂型滑脱的有效方法,PLIF在对滑脱矫形的维持及结构的稳定上具有优越的力学性能,PLF后期易出现矫正丢失及内固定失败,但临床疗效不受明显影响。  相似文献   
106.
目的探讨髋臼横形伴后壁骨折的诊断方法和治疗效果.方法15例髋臼横形伴后壁骨折,通过X线平片、CT平扫及重建图像确诊,均手术治疗,其中改良Kocher-Langenbeck(K-L)入路10例、前后联合入路5例,均采用钢板和拉力螺钉固定.结果随访1~4年(平均2年),关节功能按改良d'Aubigne和Postel功能评定标准,解剖复位者12例中关节功能优良10例、可2例;复位欠佳2例中关节功能良1例、可1例;不满意复位1例关节功能差.结论髋臼横形伴后壁骨折一般采用手术治疗,手术入路为改良K-L入路或前后联合入路,骨折固定方法应满足解剖复位、坚强固定和安全的要求.  相似文献   
107.
目的探讨应用超薄枪钳结合带槽神经钩切除脊髓型颈椎病变后纵韧带的安全性。方法回顾性分析25例脊髓型颈椎病变患者资料,均采用超薄枪钳结合带槽神经沟切除后纵韧带。结果术后JOA评分平均16.2(13~17),JOA评分改善率平均83%(48%~95%)。无严重并发症发生。结论超薄枪钳结合带槽神经钩可安全切除脊髓型颈椎病变后纵韧带。  相似文献   
108.
高选迷走神经切断贲门周围血管离断术对胃功能的影响   总被引:4,自引:0,他引:4  
目的高选迷走神经切断贲门周围血管离断术对胃功能的保护作用。方法127例门脉高压病人随机分为两组,一组行高选迷走神经切断贲门周围血管离断术为研究组,另一组行常规贲门周围血管离断术为对照组。术后以血清胃泌素、胃酸的变化及胃蠕动的恢复情况为观察指标。结果血清胃泌素研究组为(88·70±13·07)pg/ml,对照组为(75·17±11·43)pg/ml,两组对比P=0·046。基础胃酸排出量研究组为(2·36±1·01)mEq/ml,对照组为(1·03±0·88)mEq/ml,两组对比P=0·033。最大胃酸排出量研究组为(5·87±1·83)mEq/ml,对照组为(3·89±1·02)mEq/ml,两组对比P=0·026。胃肠功能恢复研究组平均为2·9d,对照组平均组为5·2d,P=0·01。结论高选迷走神经切断贲门周围血管离断术既治疗了原发病,又保护了胃功能,减少了并发症,提高了病人的生活质量。  相似文献   
109.
《Injury》2023,54(7):110761
ObjectivesHistorically, pelvic ring fractures (PRF) are considered to occur predominantly in the anterior ring and therfore to be mechanically stable. Combined anterior and posterior (A + P) PRF are expected to be less mechanically stable and therefore to be associated with higher levels of pain and reduced mobility compared to isolated anterior fractures. The current study investigates the clinical relevance of combined A + P PRF in elderly patients.MethodsA prospective multicentre cohort study was conducted in patients >70 years of age with anterior PRF after low-energy trauma diagnosed on conventional radiographs. All patients underwent an additional CT-scan. Patients were divided into two groups; isolated anterior or combined A + P fractures. Patients were treated conservatively with adequate analgesia for at least one week. If patients could not be mobilised after conservative treatment, surgical fixation was performed. Numerical Rating Scale (NRS) pain scores, dependence on walking aids and Activities of Daily Living scores (ADL) were measured at 2–4 weeks, and 3, 6 and 12 months after fracture.Results102 patients (age 81.1 ± 7.6 years) were included. Isolated anterior fractures were diagnosed in 25 (24.5%) and A + P fractures in 77 (75.5%) patients. Baseline characteristics did not differ between the two groups. Most patients were successfully treated conservatively and 5 (4.9%) underwent percutaneous trans-iliac, trans-sacral screw fixation after failure of conservative treatment. At 2–4 weeks post trauma, patients with A + P fractures had similar median pain scores (3 (range 0–8) vs. 5 (0–10), p = 0.19) and ADL scores (85 (25–100) vs. 78.6 (5–100), p = 0.67), but were more dependent on walking aids (92.8% vs. 72.2%; p = 0.02) compared to patients with isolated anterior fractures. There were no significant differences at 3 months. At one year follow-up the median NRS pain and ADL scores for both fracture groups were 0 and 100, respectively. Mortality was 10.8%, and additional loss to follow-up was 17.6%.ConclusionsThe vast majority of elderly patients with PRF have combined A + P fractures. The clinical implications of additional posterior pelvic ring fractures in elderly patients appears to be limited.  相似文献   
110.
《The Journal of arthroplasty》2023,38(8):1571-1577
BackgroundRevision total hip arthroplasty (THA) presents a greater risk to patients than primary THA, and surgical approach may impact outcomes. This study aimed to summarize acetabular revisions at our institution and to compare outcomes between direct anterior and posterior revision THA.MethodsA series of 379 acetabular revision THAs performed from January 2010 through August 2022 was retrospectively reviewed. Preoperative, perioperative, and postoperative factors were summarized for all revisions and compared between direct anterior and posterior revision THA.ResultsThe average time to acetabular revision THA was 10 years (range, 0.04 to 44.1), with mechanical failure (36.7%) and metallosis (25.6%) being the most prevalent reasons for revision. No differences in age, body mass index, or sex were noted between groups. Anterior revision patients had a significantly shorter length of stay (2.2 versus 3.2 days, P = .003) and rate of discharge to a skilled nursing facility (7.5 versus 25.2%, P = .008). In the 90-day postoperative period, 9.2% of patients returned to the emergency department (n = 35) and twelve patients (3.2%) experienced a dislocation. There were 13.2% (n = 50) of patients having a rerevision during the follow-up period with a significant difference between anterior and posterior approaches (3.8 versus 14.7%, respectively, P = .049).ConclusionThis study provides some evidence that the anterior approach may be protective against skilled nursing facility discharge and rerevision and contributes to decreased lengths of stay. We recommend surgeons select the surgical approach for revision THA based on clinical preferences and patient factors.  相似文献   
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