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1.
《Radiography》2022,28(3):663-667
IntroductionAnti-scatter grids efficiently reduce scatter radiation from reaching the imaging receptor, enhancing image quality; however, the patient radiation dose increases in the process. There is disagreement regarding the thickness thresholds for which anti-scatter grids are beneficial. This study aims to establish a thickness threshold for the use of anti-scatter grids to optimise adult knee radiography.MethodsThe study consisted of two phases. In Phase 1 phantom knee radiographs were acquired at varying thicknesses (10–16 cm) and tube voltages (60–80 kV). For each thickness and tube voltage, images with and without an anti-scatter grid were obtained. In Phase 2, two radiologists and three radiographers, evaluated the image quality of these images. Visual Grading Analysis (VGA) scores were analysed using Visual Grading Characteristics (VGC) based on the visualisation of five anatomic criteria.ResultsThe average DAP decreased by 72.1% and mAs by 73.1% when removing the anti-scatter grid. The VGC revealed that overall images taken with an anti-scatter grid have better image quality (AUC ≥0.5 for all comparisons). However, the anti-scatter grids could be removed for thicknesses 10, 12 and 14 cm in conjunction with using 80 kVp,.ConclusionAnti-scatter grids can be removed when imaging adult knees between 10 and 12 cm using any kVp setting since the radiation dose is reduced without significantly affecting image quality. For thicknesses >12 cm, the use of anti-scatter grids significantly improves image quality; however, the radiation dose to the patient is increased. The exception is at 14 cm used with 80 kVp, where changes in image quality were insignificant.Implications for practiceOptimisation by removing anti-scatter grids in adult knee radiography seems beneficial below 12 cm thickness with any kVp value. Since the average knee thickness ranges between 10 and 13 cm, anti-scatter grid can be removed for most patients. Nevertheless, further studies are recommended to test if this phantom-based threshold applies to human subjects.  相似文献   
2.
目的 探讨电视辅助胸腔镜下解剖性肺切除治疗Ⅰ期肺癌的临床效果。方法 采用回顾性研究方法,选取2015年5月至2017年1月广西医科大学附属肿瘤医院收治的I期肺癌患者84例,按照手术方法不同将患者分为两组:观察组和对照组,每组各42例。观察组患者实施电视辅助胸腔镜下解剖性肺切除术治疗,对照组患者给予传统开胸肺叶切除术治疗。比较两组患者的住院时间、切口长度、术中出血量、手术时间、1年和3年生存情况及生活质量评分(SF-36生活量表)变化。结果 观察组患者的住院时间短于对照组(6. 13±1. 46 vs. 10. 39±2. 41 d),切口长度小于对照组(4. 38±1. 09 vs. 11. 84±3. 25 cm),术中出血量少于对照组(284. 62±54. 21 vs. 397. 57±61. 49 ml),差异均具有统计学意义(P <0. 05);而两组手术时间比较(165. 28±33. 24 vs. 156. 39±30. 92 min),差异无统计学意义(P> 0. 05)。观察组患者的1、3年生存率[97. 62%(41/42)、90. 48%(38/42)]均高于对照组[88. 10%(37/42)、76. 19%(32/42)],但差异无统计学意义(P> 0. 05)。观察组患者的各项生活质量评分[精神健康(75. 42±6. 87 vs 61. 30±4. 15分)、情感职能(81. 38±7. 15 vs. 73. 49±5. 76分)、社会功能(82. 67±5. 78 vs. 75. 42±4. 35分)、一般健康状况(79. 49±6. 17 vs.70. 31±5. 04分)、精力(84. 37±5. 45 vs. 74. 13±6. 07分)、生理职能(86. 52±6. 88 vs. 76. 93±6. 42分)、躯体疼痛(83. 46±7. 49 vs. 74. 33±5. 79分)、生理功能(70. 39±4. 31 vs. 61. 38±3. 56分)]均高于对照组,且差异具有统计学意义(P <0. 05)。结论 与传统开胸肺叶切除术相比,电视辅助胸腔镜下解剖性肺切除治疗I期肺癌手术损伤更小、短期生存率更高,且有助于提高患者术后生活质量水平,这对改善患者预后有重要意义,值得临床推广应用。  相似文献   
3.
房间隔入路的解剖学研究及临床应用   总被引:3,自引:0,他引:3  
对33具尸体的房间隔的大小、构成及周围重要组织结构进行观察和测量。提出房间隔切开时的正确方向、安全长度及可能发生的危险。结合466例临床应用,讨论了避免切口合并症发生及发生后的正确处理方法。  相似文献   
4.
5.
横窦和窦汇的浅表解剖学标志   总被引:1,自引:1,他引:0  
目的为神经外科手术准确定位横窦的下缘和窦汇确定出一个可靠的浅表解剖学标志。方法对10例经10%甲醛溶液固定的尸头标本进行逐步解剖,测量各相关解剖结构到横窦下缘的距离。结果实验所收集的数据表明在定位横窦下缘和窦汇时,上项线及枕外隆凸尖不是一个可靠的浅表解剖学标志。而以半脊肌附着点作为浅表解剖学标志比以上项线作为浅表解剖标志更准确、可靠。本组10例标本中,无1例的半脊肌附着点超过横窦下部边界3mm,并且它可以作为一个可靠的浅表解剖学标志用以定位接近中线部分的横窦。结论这些发现可以帮助神经外科医生在治疗后颅窝和颅颈接合处病变而进行的各种中线入路手术时更准确的定位横窦。  相似文献   
6.
An arthroscopic and anatomical investigation was performed to define the abnormal conditions of the popliteal tendon area in a lateral meniscus. Arthroscopic findings for 100 patients and anatomical observations of 10 amputated knees were analyzed. Five of the 10 dissected menisci were also examined histologically. Menisco-tibial coronary ligaments were classified into two types, as follows: type I--a coronary ligament covering an entire popliteal tendon beneath the meniscus; type II--a popliteal tendon visible beneath the meniscus through defects of the coronary ligament. Twenty-one of 100 cases were classified as type I, and 79 were classified as type II. Three of the 10 anatomical dissections were type I, and the remaining 7 were type II. Menisci in which the type I coronary ligaments were thought to be torn and menisci with type II coronary ligaments showed a rather marked mobility, but no conclusion could be reached.  相似文献   
7.
A 60-year-old Japanese man was hospitalized because of urinary leakage from the anus on October 3, 1994. Retrograde urethrography detected a fistula between the bulbous urethra and the rectum. Urethrocystoscopy revealed a tumor on the urethrorectal fistula. Tumor biopsy showed a well differentiated adenocarcinoma. Cystourethrectomy with fistulectomy, and ileal conduit urinary diversion were performed. Pathological examination revealed primary adenocarcinoma in the fistula with invasion to the prostatic urethra and bladder wall. The patient showed no evidence of a recurrence as of August, 1996.  相似文献   
8.
92例跟骨骨折后足部畸形功能障碍治疗探讨   总被引:6,自引:1,他引:5  
本文对92例106足波及距下关节的跟骨骨折治疗后1~6年遗留足畸形、功能障碍的病例(PALey:舌型17足,中央压陷型53足,严重粉碎型36足)进行了分析和总结。作者强调解剖复位、牢靠固定、一期植骨、早期关节持续被动运动及不过早负重是预防跟骨骨折众多并发症的重要措施。  相似文献   
9.
回顾5例由于神经根变异或特殊类型椎间盘突出引起的腰腿痛病人,对其病理及术中处理做了介绍,认为由于神经根的解剖变异,更容易受到椎间盘突出的卡压。手术中如临床症状符合椎间盘突出症,而预定探查间隙未发现突出物,或与临床症状不符者,应根据神经根激惹及松紧程度,扩大探查范围,查明造成疼痛的原因,避免二次手术。  相似文献   
10.
Normal skeletal variants are a common occurrence in clinical practice and may lead to misinterpretation. As part of a case control study investigating the carpal tunnel, our asymptomatic and voluntary participant underwent magnetic resonance (MR) imaging of both wrists from the metacarpal bases to the distal radiocarpal joint. The imaging techniques included spin echo (SE), turbo spin echo (TSE) and fast field echo (FFE) sequences using 4 mm-slice thickness. As an incidental finding bipartite hamulus was detected bilaterally. The anomaly was evident in both hamuli with similar MRI characteristics. The congenital origin was further supported by the absence of trauma or surgery to the wrists. In this case report the authors discuss the anatomical variant, bilateral bipartite hook of the hamate, and demonstrate the reliability of contiguous slices of MR axial slices in displaying an anatomical variant of the carpus. This normal variant of the hamate is not commonly encountered in MR imaging of the wrist and can be misinterpreted as fracture or post-traumatic sequelae. Images of the normal hamulus are presented for comparison.  相似文献   
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