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This study reports an independent audit of two aspects of orthognathic surgery, namely control of inter-alar width and mandibular outline asymmetry. Measurements were taken from standardized photographs of a consecutive series of 27 patients, using an on-screen digitizing program (IPTool).All patients had undergone bimaxillary osteotomies involving maxillary impaction and/or advancement, by one surgeon, using a cinch suture for nasal width control. Nine-twelve months after surgery, inter-alar width had increased by just 0.08 cm mean (SD 0.3). Four patients showed an increase of just over 2 mm, whilst six showed a small reduction.Based on ratios of size (area) and shape (compactness) of the right and left mandibular segments, there was a small overall improvement in mandibular symmetry (0.019 and 0.005 respectively). Whilst in most of the patients the need for surgery was primarily the correction of antero-posterior and vertical discrepancies, five patients with demonstrable asymmetry showed a clear improvement. In three patients whose asymmetry scores were very mild pre-treatment, there was a small, measured increase in asymmetry, but not to a degree that would be clinically noticeable.At a time when 3D imaging is still unavailable to many clinicians, the results of this study suggest that appropriate measurements taken from carefully standardized conventional photographs can provide a valid and objective means of assessing treatment outcome.  相似文献   
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Unilateral condylar hyperplasia (UCH) of the mandible is a disorder affecting the condyle size, resulting in facial asymmetry. This study was a retrospective review of 27 patients with UCH who underwent condylectomy between 2000 and 2017 at Yonsei University Dental Hospital. Patient demographic characteristics were summarized. UCH was divided into three subtypes: hemimandibular elongation (HE, n = 15), hemimandibular hyperplasia (HH, n = 4), and osteochondroma (OC, n = 8). Of the 27 patients, only one with the HE type and five (18.5%) with the OC type complained of joint pain. Bone scans of all patients showed higher uptake on the UCH side. Lip and maxillary canting was prominent in the HH and HE types. Five patients (18.5%) underwent condylectomy alone, 13 (48.1%) underwent condylectomy with orthodontic treatment, and nine (33.3%) underwent adjunctive jaw surgery with orthodontic treatment. The treatment modalities varied according to the subtype. In all OC type patients, removal of the hyperplastic condyle treated the facial asymmetry. Additional post-surgical orthodontic treatment was necessary in only three cases (37.5%). All HH type patients required mandibuloplasty. All patients showed a stable occlusal outcome without relapse and an improvement in subjective symptoms, despite a decrease in mouth opening of 2.2 mm. These findings might be useful in treatment planning for UCH patients.  相似文献   
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Purpose:

To elucidate differences in activity and connectivity during early learning due to the performing hand.

Materials and Methods:

Twenty right‐handed subjects were recruited. The neural correlates of explicit visuospatial learning executed with the right, the left hand, and bimanually were investigated using functional magnetic resonance imaging. Connectivity analyses were carried out using the psychophysiological interactions model, considering right and left anterior putamen as index regions.

Results:

A common neural network was found for the three tasks during learning. Main activity increases were located in posterior cingulate cortex, supplementary motor area, parietal cortex, anterior putamen, and cerebellum (IV–V), whereas activity decrements were observed in prefrontal regions. However, the left hand task showed a greater recruitment of left hippocampal areas when compared with the other tasks. In addition, enhanced connectivity between the right anterior putamen and motor cortical and cerebellar regions was found for the left hand when compared with the right hand task.

Conclusion:

An additional recruitment of brain regions and increased striato‐cortical and striato‐cerebellar functional connections is needed when early learning is performed with the nondominant hand. In addition, access to brain resources during learning may be directed by the dominant hand in the bimanual task. J. Magn. Reson. Imaging 2013;37:619–631. © 2012 Wiley Periodicals, Inc.  相似文献   
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ObjectivesTo evaluate the performances of systematic posttreatment pelvic magnetic resonance imaging (PPMRI) in predicting prognosis of patients treated with chemoradiation therapy (CRT) for locally advanced cervical cancer (LACC).Materials and methodsMulti-institutional data from 216 patients presenting FIGO IB2-IIB cervical cancer for which PPMRI was performed following CRT were retrospectively reviewed. Incomplete response was defined as the identification of persistent lesion on PPMRI. Primary endpoints were patients’ 5-year recurrence free (RFS) and overall (OS) survivals. Secondary endpoint was the identification of residual histologic disease on hysterectomy specimens when completion surgery was performed.ResultsPPMRI identified an incomplete response in 102 (47.2%) cases. A 70% or more reduction in tumor size on PPMRI was identified as the best predictive cut-off for recurrence (37.7% sensitivity and 78.7% specificity) and death (50% sensitivity and 77.9% specificity) with significant impact on those risks (HRa: 0.42; 95%CI: 0.23–0.77 and HRa: 0.18; 95%CI: 0.06–0.50, respectively). Completion hysterectomy was performed in 117 (54.4%) cases, with histologic residual disease in 55 (47.4%). PPMRI demonstrated 74.5% sensitivity and 50.8% specificity in predicting residual disease. Although survival of patients with complete response at PPMRI was not impacted by completion hysterectomy, it significantly increased 5-year RFS and OS of those with incomplete response: 38.7% vs. 65.3% (p < 0.001) and 63% vs. 82.9% (p = 0.038), respectively.ConclusionA 70% or more reduction of in tumor size on PPMRI following CRT in patients with LACC is predictive of RFS and OS. PPMRI could help triaging patients who could benefit from completion hysterectomy.  相似文献   
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目的 评价数字化软件辅助设计在治疗偏颌畸形患者中的应用效果。方法 选择2016年9月至2018年9月于中国医科大学附属口腔医院口腔颌面外科就诊的偏颌畸形患者18例。所有患者术前完成三维CT检查和牙列石膏模型的光学扫描,将数据分别以DICOM格式和STL格式传送至数字化工作站。在数字化软件中构建坐标系,重建上下颌骨、血管和神经束,并完成正颌外科的手术模拟预测,最后设计并打印患者上颌骨的截骨导板、复位导板和终末咬合导板。所有患者在术后6个月到口腔颌面外科门诊复查并行上下颌骨三维CT检查。利用数字化软件测量术后6个月患者两侧上颌第一磨牙点和尖牙点到眶耳平面和冠状平面的距离,计算非对称率;测量上中切牙点和颏顶点到正中矢状面距离作为术后效果的评价指标。结果 术后6个月患者两侧上颌第一磨牙点到眶耳平面和冠状平面距离的非对称率分别为(1.8 ± 1.0)%和(3.2 ± 1.7)%;两侧上颌尖牙点到眶耳平面和冠状平面距离的非对称率分别为(1.0 ± 0.8)%和(11.0 ± 4.8)%;上中切牙点和颏顶点到正中矢状面距离分别为(0.84 ± 1.05)mm和(1.49 ± 1.23)mm。所有患者均对面型表示满意。结论 数字化软件的模拟设计能够提高手术安全性,确保术中操作的精度,提高患者术后美学效果。因此,数字化软件辅助设计在治疗偏颌畸形患者中的应用具有重要的临床意义。  相似文献   
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