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Matthew J Ziegelmann Petar Bajic Laurence A Levine 《International journal of urology》2020,27(6):504-516
Peyronie’s disease is a common yet poorly understood condition characterized by penile pain, curvature, sexual dysfunction and psychological bother. Peyronie’s disease represents a penile wound healing disorder, and is thought to arise from exuberant scarring in response to penile trauma in genetically predisposed men. In the absence of active treatment, the majority of men experience stable or worsening symptoms, with few reporting spontaneous resolution in penile curvature or other deformity. In contrast, penile pain improves or resolves in the majority of men. Treatment options vary based on symptom severity and stability. Several oral therapies are commonly prescribed, although to date there are no strong data to support any oral agents as monotherapy for Peyronie’s disease. Other options including penile traction therapy and intralesional injections result in modest improvements for many patients, particularly when used early after symptom onset. Penile straightening through approaches, such as penile plication and plaque incision or partial excision and grafting, represent the most rapid and reliable approach to correct penile curvature once the symptoms have stabilized. Side-effects vary based on the type of surgery carried out, and include penile shortening, sensation changes and erectile dysfunction in the minority of men. In patients with drug refractory erectile dysfunction and Peyronie’s disease, placement of a penile prosthesis will address both issues, and is associated with high levels of patient satisfaction. The current review provides a practical approach to the modern evaluation and management of patients presenting with Peyronie’s disease. 相似文献
3.
Three-dimensional spinal curvature in idiopathic scoliosis 总被引:3,自引:0,他引:3
Scoliosis is usually considered as a deformity of the spine in the frontal plane, without reference to curvatures in other planes. In this study, the three-dimensional shape of the spine of 104 patients with untreated idiopathic scoliosis (5-55 degrees Cobb) was studied by means of stereo radiographs to determine relationships between curvature of the spine in the frontal plane view, in the lateral view, and in the intermediate views. There was a weak but statistically significant correlation (r = 0.2) relating greater scoliosis with lesser kyphosis or greater lordosis. In the thoracic region, the sagittal plane spinal curvature was less than that measured in a population without scoliosis (mean difference, 7.72 +/- 9.9 degrees). Seventy-four of 76 scolioses in the upper region of the spine with lateral curvature greater than 5 degrees Cobb were kyphotic. Sixty-four of 84 curves greater than 5 degrees Cobb in the lower region were lordotic. Measuring curvatures in the plane of symmetry of the rotated apical vertebra altered these ratios to 69 of 76 kyphotic in the upper region and 68 of 84 lordotic in the lower region. The plane of maximum curvature of sections of the spine with scoliosis was not related to the plane of symmetry of the rotated apical vertebra, for in kyphotic regions of the spine the rotations of these two planes were in opposite directions. In all cases, the magnitudes of the rotations were quite different, i.e., by a factor of -0.22 for curves in thoracic region and by a factor of 0.24 for curves in the lumbar region. This implies that mechanical measures to correct this spinal deformity or to prevent progression should apply different rotations to the apex from those applied to the curve as a whole and, in opposite senses, in curves in kyphotic regions. There was no evidence of an abnormality of sagittal curvature of a magnitude to implicate it in the etiology or in the treatment. 相似文献
4.
本文应用计算机辅助的角膜地形图系统TMS-1和角膜曲率计TOPCONOM-4同时测定了200例(278眼)的角膜地形图和中央角膜屈光状态。比较了角膜地形图的模拟角膜曲率SIMK值和角膜曲率计的垂直和水平屈光度。结果显示,白内障术前组116例150眼的SIMK平均值分别为44.22D(垂直轴)和44.26D(水平轴),角膜曲率计的中央屈光度垂直轴平均为44.16D,水平轴为44.23D。统计学处理表明,2种组方法的结果之间差异无显著性(P>0.05),第2种术后组67例90眼的SIMK平均值分别为46.37D(垂直轴)和43.06D(水平轴),角膜曲率计的中央屈光度垂直轴平均为46.09D,水平轴平均为42.88D,统计学处理二种方法的结果之间差异无显著性(P>0.05)。研究提示,角膜地形图系统的模拟角膜曲率SIMK值和角膜曲率计的屈光度无论在白内障手术前还是在手术后其结果是一致的,临床应用具有同等的价值。但是,当角膜中央屈光度异常范围小于3毫米,角膜混浊,角膜严重不规则散光时,角膜曲率计不能满足临床需要。而计算机辅助的角膜地形图系统则具有极大的诊断及检测价值。眼科学报 1994;10:85—89。 相似文献
5.
特发性颈椎后凸畸形的手术治疗 总被引:3,自引:1,他引:2
目的 :明确颈椎前路手术治疗特发性颈椎后凸畸形的可行性和局限性。方法 :本文对 14例颈椎特发性后凸畸形患者采取手术方法进行治疗 ,所有患者均采用颈椎前路椎间盘切除减压 ,椎间隙植骨和前路钢板内固定。结果 :手术后患者临床体征明显改善 ,颈椎后凸畸形由手术前平均 -15 6°矫正为手术后平均 -6 4° ,矫正效果明显 ;手术后患者的短期随访表明颈椎矫正度数在随访中没有丢失。结论 :前路手术 ,延长颈椎前柱能够矫正颈椎的后凸畸形 ,改善临床症状和体征 相似文献
6.
两种根管弯曲度测量法间数学关系的推导 总被引:5,自引:0,他引:5
目的:研究2种根管弯曲度测量法测值(Schneider法的测值为θS,Weine法的测值为θW)间的数学关系。方法:将弯曲根管长轴简化为依次由相切的线段(长度为l1)、圆弧(半径为r、圆心角为θ)、线段(长度为l2)组成的连线,根据2测量法确定简化弯曲根管长轴测量角时不同的定点、连线方式,推导θS、θW间的函数方程以及与l1、l2、r、θ间的数学关系,分析方程与函数图形的特征。结果:θS与θW间存在以下数学关系:(1)tanθS=(1-cosθW ksinθW)/(sinθW kcosθW),k=l2/r;(2)θW/2≤θS≤θW。k取不同值时函数曲线的形态具有不同的特点。θW在0,π的区间内,θS与θW间呈近似的线性关系;k越大,θS越接近θW,k越小,θS越接近θW/2。结论:Schneider法与Weine法测值间存在着复杂的函数关系,根管根尖部直段的长度(l2)与弯曲段曲率半径(r)之比值是影响2种方法测值间差异的重要因素。 相似文献
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Araabi BN Kehtarnavaz N McKinney T Hillman G Würsig B 《Annals of biomedical engineering》2000,28(10):1269-1279
This paper presents a syntactic/semantic string representation scheme as well as a string matching method as part of a computer-assisted system to identify dolphins from photographs of their dorsal fins. A low-level string representation is constructed from the curvature function of a dolphin's fin trailing edge, consisting of positive and negative curvature primitives. A high-level string representation is then built over the low-level string via merging appropriate groupings of primitives in order to have a less sensitive representation to curvature fluctuations or noise. A family of syntactic/semantic distance measures between two strings is introduced. A composite distance measure is then defined and used as a dissimilarity measure for database search, highlighting both the syntax (structure or sequence) and semantic (attribute or feature) differences. The syntax consists of an ordered sequence of significant protrusions and intrusions on the edge, while the semantics consist of seven attributes extracted from the edge and its curvature function. The matching results are reported for a database of 624 images corresponding to 164 individual dolphins. The identification results indicate that the developed string matching method performs better than the previous matching methods including dorsal ratio, curvature, and curve matching. The developed computer-assisted system can help marine mammalogists in their identification of dolphins, since it allows them to examine only a handful of candidate images instead of the currently used manual searching of the entire database. © 2000 Biomedical Engineering Society.
PAC00: 8780Tq, 4230Sy, 0705Pj 相似文献
9.
根据点,线、面的运动轨迹可以形成曲面的原理,应用投影方法将空间轨迹降低为平面上的轨迹,再使平面轨迹按规律运动形成空间曲面,在此基础上获取曲面上点的主曲率和主方向。 相似文献
10.
目的:探讨青少年特发性脊柱侧弯(adolescent idiopathic scoliosis,AIS)胸腰椎生理曲度变化情况以及不同类型侧弯之间胸腰椎生理曲度的差异。方法:自2017年1月至2021年12月回顾性分析305例脊柱全长正侧位X线片的青少年患者,根据有无侧弯分为正常组和侧弯组。正常组179例,男79例,女100例;年龄10~18(12.84±2.10)岁。侧弯组126例,男33例,女93例;年龄10~18(13.92±2.20)岁。观察并比较两组Risser征、胸椎后凸角(thoracic kyphosis,TK)与腰椎前凸角(lumbar lordosis,LL),并分析比较不同性别、不同程度侧弯与不同节段侧弯TK值与LL值。结果:侧弯组在女性比率(P=0.001)、年龄(P<0.001)方面均明显高于正常组;Risser征方面,正常组低级别骨化程度比率明显高于侧弯组(P=0.038)。侧弯组TK值明显小于正常组(P<0.001),而两组LL值比较,差异无统计学意义(P=0.147)。男性与女性之间比较,TK值与LL值差异无统计学意义。轻度侧弯TK值明显大于中度侧弯(P<0.05),但LL值比较,差异无统计学意义(P>0.05)。不同节段侧弯之间TK值与LL值比较,差异均无统计学意义(P>0.05)。结论:胸椎与腰椎生理曲度均与性别无关;AIS患者胸椎生理曲度变小,但是腰椎生理曲度基本不变。轻度AIS患者的胸椎生理曲度大于中度AIS患者,但是腰椎生理曲度在轻中度患者之间几乎无差异,且与正常青少年相似。AIS患者胸腰椎生理曲度变化可能与脊柱前柱相对生长过快有关,其具体机制有待进一步研究。 相似文献