CR全脊柱数字化成像技术的应用与比较

脊柱侧凸的常规检查方法是全脊柱X线正、侧位摄片,来反映脊柱侧凸畸形的状况。脊柱侧凸的X线检查要求每张脊柱正、侧位片,包含上自颈椎和双侧肩部,下至骨盆和髋关节在内的全脊柱,可以反映畸形的真实面貌和平衡情况。一张拼接好的X线片对青少年特发性脊柱侧凸进行手术前评估和脊柱侧凸三维矫形的预测有重要意义[1]。以前多采用超长感绿X线胶片(30 cm×61 cm)一次曝光[2];后采用多块IP板一次曝光,并将图像在计算机内进行拼接,但其拼接密度的均匀性和准确性不太理想。本院引进富士CR超长IP板,进行全脊柱一次曝光摄片。笔者就多块IP板一次…     

脊柱侧凸的X线诊断与评估(一)

脊柱侧凸是青少年常见病,X线是诊断和评估脊柱侧凸的主要手段。X线对侧凸程度、侧凸类型、躯干平衡、进展风险等方面的评估为临床诊断和治疗方案的选择提供了重要依据。     

青少年重度脊柱侧凸的影像学评价

目的:探讨青少年重度脊柱侧凸的影像学诊断价值。材料和方法:65例重度脊柱侧凸患者行X线平片、CT、MR I检查。结果:65例脊柱侧凸,X线平片显示主弯术前平均Cobb角102.3,°术后平均Cobb角48.4;°CT测量椎弓根平均深度47mm、椎弓根横径平均6.6m,椎管内纵行骨嵴10例。MR I检查发现脊髓异常26例。结论:青少年重度脊柱侧凸需要进行手术治疗,综合影像学检查可以提供全面的影像资料,为术前诊断提供有用的信息;术后复查根据需要选择X线平片、CT。     

MSCT后处理技术诊断特发性脊柱侧凸畸形的临床价值

目的：探讨MSCT后处理技术在特发性青少年脊柱侧凸畸形中的临床价值。方法：搜集2008年～2009年我院特发性青少年脊柱侧凸畸形病例25例,均行脊柱X线正、侧位片,MSCT检查及三维重建。在经验丰富的外科医生指导下进行Lenke分型、腰椎侧凸修正分型、胸椎矢状面后凸分型,并结合MSCT后处理技术影像学资料及术中数据进行综合评价,评估MSCT后处理技术在外科学脊柱侧凸分型中的应用价值。结果：Lenke Ⅰ型11例,最为多见;Lenke Ⅲ型5例,Lenke Ⅴ型7例,Lenke Ⅵ型2例。腰椎侧凸进一步分型中,A型6例,B型5例,C型14例。胸椎侧凸矢状面进一步分型,正常20例,后凸角度增大2例,后凸角度减小3例。结论：MSCT后处理技术是Lenke分型的补充,也是Lenke分型弯曲类型、腰弯修正型、胸椎矢状面修正型三种基本类型有机、立体、直观的结合在一起的桥梁。     

全脊柱CR单次曝光与多次曝光成像的比较

脊柱侧弯(或称脊柱侧凸)是青少年常见的躯干畸形,国内患病率为10.7‰~21‰[1~5]。脊柱侧弯不论在患病率普查,还是治疗方案的确定,Cobb角是非常重要的测量参数,而测量Cobb角需要摄脊柱全长X线片,但X线胶片的最长规格只有43 cm,要摄取全脊柱X线片,传统方法是分段拍摄,然后将多张片在观片灯上拼接读片,这样测量Cobb角会产生误差。在1张照片上摄取全脊柱X线影像,一直是临床脊骨科医生的迫切希望。我院应用计算机X线摄影(CR)图像,采用数字影像拼接技术,将多幅脊柱图像拼接成全脊柱片,成功地拼接了69例脊柱侧弯的全脊柱影像,效果不错,现报告如…     

螺旋CT低剂量扫描在青少年脊柱侧弯病变中的应用

脊柱侧弯多发生于6～14岁学龄儿童和青少年.以往通过传统X线平片来达到诊断目的,但由于这些平面图像存在着变形、放大、影像重叠、无立体感的缺点,使骨科医生对脊柱侧弯畸形的定位、测量、术前计划的制定和术后的疗效评估造成一定困难,而螺旋CT则弥补了这方面的缺陷.本研究用16层螺旋CT在保证图像质量的前提下,分别用传统扫描和Care Dose模式在其手术前后行全脊柱扫描,并对不同扫描检查辐射剂量进行对照研究.     

螺旋CT低剂量扫描在青少年脊柱侧弯病变中的应用

脊柱侧弯多发生于6～14岁学龄儿童和青少年.以往通过传统X线平片来达到诊断目的,但由于这些平面图像存在着变形、放大、影像重叠、无立体感的缺点,使骨科医生对脊柱侧弯畸形的定位、测量、术前计划的制定和术后的疗效评估造成一定困难,而螺旋CT则弥补了这方面的缺陷.本研究用16层螺旋CT在保证图像质量的前提下,分别用传统扫描和Care Dose模式在其手术前后行全脊柱扫描,并对不同扫描检查辐射剂量进行对照研究.     

螺旋CT低剂量扫描在青少年脊柱侧弯病变中的应用

脊柱侧弯多发生于6～14岁学龄儿童和青少年.以往通过传统X线平片来达到诊断目的,但由于这些平面图像存在着变形、放大、影像重叠、无立体感的缺点,使骨科医生对脊柱侧弯畸形的定位、测量、术前计划的制定和术后的疗效评估造成一定困难,而螺旋CT则弥补了这方面的缺陷.本研究用16层螺旋CT在保证图像质量的前提下,分别用传统扫描和Care Dose模式在其手术前后行全脊柱扫描,并对不同扫描检查辐射剂量进行对照研究.     

螺旋CT低剂量扫描在青少年脊柱侧弯病变中的应用

脊柱侧弯多发生于6～14岁学龄儿童和青少年.以往通过传统X线平片来达到诊断目的,但由于这些平面图像存在着变形、放大、影像重叠、无立体感的缺点,使骨科医生对脊柱侧弯畸形的定位、测量、术前计划的制定和术后的疗效评估造成一定困难,而螺旋CT则弥补了这方面的缺陷.本研究用16层螺旋CT在保证图像质量的前提下,分别用传统扫描和Care Dose模式在其手术前后行全脊柱扫描,并对不同扫描检查辐射剂量进行对照研究.     

螺旋CT低剂量扫描在青少年脊柱侧弯病变中的应用

脊柱侧弯多发生于6～14岁学龄儿童和青少年.以往通过传统X线平片来达到诊断目的,但由于这些平面图像存在着变形、放大、影像重叠、无立体感的缺点,使骨科医生对脊柱侧弯畸形的定位、测量、术前计划的制定和术后的疗效评估造成一定困难,而螺旋CT则弥补了这方面的缺陷.本研究用16层螺旋CT在保证图像质量的前提下,分别用传统扫描和Care Dose模式在其手术前后行全脊柱扫描,并对不同扫描检查辐射剂量进行对照研究.     

Scoliosis imaging: An analysis of radiation risk in the CT scan projection radiograph and a comparison with projection radiography and EOS

IntroductionScoliosis is defined as a deformity of the spine with lateral curvature in the coronal plane. It requires regular X-ray imaging to monitor the progress of the disorder, therefore scoliotic patients are frequently exposed to radiation. It is important to lower the risk from these exposures for young patients. The aim of this work is to compare organ dose (OD) values resulting from Scan Projection Radiograph (SPR) mode in CT against projection radiography and EOS^® imaging system when assessing scoliosis.MethodsA dosimetry phantom was used to represent a 10-year old child. Thermoluminescent dosimetry detectors were used for measuring OD. The phantom was imaged with CT in SPR mode using 27 imaging parameters; projection radiography and EOS machines using local scoliosis imaging procedures. Imaging was performed in anteroposterior, posteroanterior and lateral positions.Results17 protocols delivered significantly lower radiation dose than projection radiography (p < 0.05). OD values from the CT SPR imaging protocols and projection radiography were statistically significant higher than the results from EOS. No statistically significant differences in OD were observed between 10 imaging protocols and those from projection radiography and EOS imaging protocols (p > 0.05).ConclusionEOS has the lowest dose. Where this technology is not available we suggest there is a potential for OD reduction in scoliosis imaging using CT SPR compared to projection radiography. Further work is required to investigate image quality in relation to the measurement of Cobb angle with CT SPR     

Evaluation of cumulative effective dose and cancer risk from repetitive full spine imaging using EOS system: Impact to adolescent patients of different populations

ObjectiveTo evaluate the effective dose and associated cancer risk using EOS system for scoliotic adolescent patients undergoing full spine imaging at different age of exposure; to demonstrate EOS system capable of delivering less radiation dose and hence of reducing cancer risk induction when compared with conventional digital X-ray systems; to obtain cumulative effective dose and cancer risk for both genders scoliotic adolescence of US and Hong Kong population.MethodsOrgan absorbed doses of full spine exposed scoliotic adolescent patients using EOS system have been simulated with the use of patient imaging parameters input to the Monte Carlo software PCXMC. Gender specific effective dose has been calculated with the simulated organ absorbed dose using the ICRP-103 approach. The associated radiation induced cancer risk, expressed as lifetime attributable risk (LAR), has been estimated according to the method introduced in the Biological Effects of Ionizing Radiation VII report. Values of LAR were estimated for scoliotic patients exposed repetitively during their follow up period at different adolescent age for US and Hong Kong population.ResultsThe effective dose of full spine imaging with posteroanterior and lateral projection for patients exposed at the age between 10–18 years using the EOS system low dose protocol was calculated between 86 and 140 μSv. The corresponding LAR for US and Hong Kong population was ranged between 0.81 × 10⁻⁶ and 6.00 × 10⁻⁶. Cumulative effective dose and cancer risk during follow-up period can be estimated using the results and are of information to patients and their parents.ConclusionWith the use of computer simulation and analytic formulation, we obtained the cumulative effective dose and cancer risk at any age of exposure for adolescent patients of US and Hong Kong population undergoing repetitive full spine imaging using the EOS system. Female scoliotic patients would be at a statistically significant higher effective dose and cumulative cancer risk than the male patients undergoing the same EOS full spine imaging protocol.     

Organ doses and lifetime attributable risk evaluations for scoliosis examinations of adolescent patients with the EOS imaging system

Purpose

The goal of this work is to evaluate organ doses and lifetime attributable risk of cancer incidence and mortality in scoliosis examinations of adolescent patients performed with EOS imaging system, in order to optimize patient dose and protocols.

Methods

An anthropomorphic phantom of a normal patient, with thermoluminescent dosimeters in correspondence with the main organs at risk, was imaged with both EOS and computed radiography (CR). For each modality, effective dose was calculated from the measured organ doses. Lifetime attributable risk was computed accordingly to the Committee on the Biological Effects of Ionizing Radiation (BEIR VII) and Public Health England (HPA) publications.

Results

Except for testes and eyes, which were excluded from the scan in CR protocol, for all the other organs the doses delivered with CR examination were higher than these delivered by EOS system. The effective dose in EOS examination (0.43 ± 0.04 mSv) is about two times less than the dose in computed radiography with anti-scatter grid examination (0.87 ± 0.09 mSv), and, consequently, also the cancer probability is lower (5.4 vs 9.7 number of any cancers induction cases per 100,000 person examined, for a 20-year-old male patient).

Conclusions

The EOS system is efficient in limiting patient dose. The shielding of testes and the exclusion of eyes from the scan could allow to further reduce the dose.

     

Radiographic signs of acetabular retroversion using a low-dose slot-scanning radiographic system (EOS®)

IntroductionAcetabular retroversion is assessed using pelvic X-ray. Cross-over-sign (COS), posterior-wall-sign (PWS) and ischial-spine-sign (ISS) are important radiographic signs of the condition. The pelvic area is sensitive to radiation and thus, possibilities to reduce dose should be considered. The purpose was to compare radiographic signs of acetabular retroversion on conventional pelvic anteroposterior (AP) X-rays with a low-dose slot-scanning system (EOS) in a sample of patients with retroversion of the acetabulum and to compare the radiation doses.Methods34 participants with radiographic signs of acetabular retroversion in one or both hips on conventional pelvic X-ray were consecutively recruited. Pelvic EOS-images were acquired in each patient and COS, PWS, ISS, COS-ratio and PWS-ratio was assessed. Radiation dose comparison of X-ray vs. EOS was performed using Dose-Area Products.ResultsRetroversion was present in 57 out of 68 hips. The absolute agreement was 91%, 84% and 76% for COS, PWS and ISS, respectively. No statistically significant differences were present between COS-ratio and PWS-ratio in either modality and Bland–Altman limits of agreement were narrow. The mean radiation dose was 1053 mGy*cm² in X-ray and 593 mGy*cm² in EOS (p = 0.003).ConclusionThe results indicate that pelvic EOS provides diagnostic qualities similar to conventional X-ray using 44% less radiation when radiographic signs of acetabular retroversion are assessed.     

Spinal deformity after intra-operative radiotherapy for paediatric patients

The purpose of this study was to clarify the incidence and characteristics of late-onset complications of the spine in children who underwent intra-operative radiation therapy (IORT) for common paediatric malignant tumours. 12 children with more than 4 years of follow-up after IORT were included and, in 11 of these, thoracic and/or lumbar spines were irradiated. To compare doses of irradiation to the spine with the resulting deformities, dose simulations of IORT were carried out on two selected cases using a radiation treatment planning system with a pencil-beam algorithm. The mean follow-up period was 135 months (range, 53–234 months). Radiographic reviews found spinal deformity in six patients. Only one patient was symptomatic and the spinal deformity was severe (Grade 3), whereas spinal deformity was mild in the remaining five patients without clinical symptoms (Grade 1). In all of the six patients, anterior wedge-shaped deformity was dominant, and scoliosis was found in only two patients. In one particular case with nephrectomy, irradiation had penetrated much deeper than usual at the site of nephrectomy, and dose distribution was asymmetric, causing clinically significant spinal deformity with scoliosis. In conclusion, specific deformities of the spine observed after IORT can be explained on the basis of dose distribution of the electron beam to the spine.Identification of late morbidity of paediatric cancer therapy has become increasingly important, as recent therapeutic developments have improved the survival rate of affected children. Radiation-induced bone injury is one of the hazardous problems: a high dose of radiation therapy impairs bone growth and gives rise to physical disabilities in affected children. Late complications following skeletal irradiation for childhood tumours have been reported previously [1–6].Intra-operative radiation therapy (IORT) is a technical refinement of radiation therapy that allows sparing of the dose-limiting tissues adjoining the target region. Following gross tumour removal, surgical displacement of critical organs or shielding of adjacent structures is carried out to minimise the radiation damage to the normal structure, and at the same time to deliver an effective irradiation dose to the therapeutic target in a single session. A high dose of electron beam irradiation with the proper acceleration energy can be delivered to residual tumours at the surgical site and neighbouring areas at high risk for microscopic disease. Combined with intensive chemotherapy, IORT has been applied successfully to paediatric malignant tumours [7–15]. In general, IORT has fewer and less severe adverse effects than conventional radiation therapy (external beam radiation therapy (EBRT)). However, the prevalence of arterial and ureteral stenosis following IORT has attracted particular attention recently [16]. The reason that IORT and EBRT are associated with different patterns of complications may result from differences in dose fractionation and distribution between electron beams and high-energy X-ray beams. Moreover, electron beams have a shorter range in bony tissue than X-ray beams and therefore present very different dose distribution patterns to X-rays. This suggests that the biological effects of IORT may be particularly unpredictable in the paraspinal region of patients. The purpose of this study was to clarify the incidence and characteristics of late-onset complications of the spine in children who underwent IORT for common paediatric malignant tumours (mostly for neuroblastoma). We focused on serial radiological changes and reviewed the medical records of long-term survivors retrospectively.     

X线平片与螺旋CT对先天性脊柱侧弯的应用价值

目的探讨多层螺旋CT(MSCT)和X线平片对于先天性脊柱侧弯的诊断价值。方法对临床诊断为先天性脊柱侧弯的40例患者行脊柱CT扫描,经最大密度投影(MIP)、多平面图像重组(MPR)、表面容积遮盖(SVR)及表现遮盖图像(SSD)后处理,并对照X线平片分析不同的处理后图像的应用价值。结果术前X线平片诊断脊椎形成障碍18例,脊椎分节障碍15例,混合型7例。MSCT诊断脊椎形成障碍13例,脊椎分节障碍12例,混合型15例,伴有脊柱纵裂6例,肋骨畸形8例,椎管内纵行骨嵴4例。SVR图像可较全面地评价先天性脊柱侧弯的所有相关表现。结论MSCT的多种后处理图像较X线平片更具优势,能准确和全面判断脊柱畸形的类型和范围。     

Imaging in scoliosis: what,why and how?

Scoliosis may be a spinal manifestation of underlying disease and although most cases of scoliosis are idiopathic, imaging plays a very important role in determining the underlying aetiology and in monitoring the changes of the deformity that take place with growth. As a clinical problem scoliosis may present directly to the radiology department through a primary healthcare referral, or it may be referred from the paediatric, orthopaedic, spinal and neurosurgical hospital services. Growth affects all types of scoliosis irrespective of cause. There are no reliable predetermined algorithmic steps in the management of scoliosis, and treatment decisions require the inclusion of multiple extrinsic (e.g age, menarche) and intrinsic (curve magnitude, vertebral anomaly) factors. It is important to remember that most of what is known about curve behaviour and its progression applies to idiopathic scoliosis, and it is inappropriate to apply these criteria to the other specific types of scoliosis. It is imperative that radiation techniques are used judiciously to minimize the radiation burden. Although magnetic resonance imaging (MRI) has had a significant impact in the understanding of the scoliotic deformity, it is still evolving and it may well eventually play a very important role in uncovering the underlying aetiology of 'idiopathic' scoliosis.     

16层螺旋CT三维和多平面重组对儿童先天性脊柱侧弯的评价

目的 运用16层螺旋CT三维（3D）和多平面重组技术对先天性脊柱侧弯患儿进行评估，探讨此技术的优势和临床指导意义。方法 搜集2004年4至10月司27例先天性脊柱侧弯患儿的影像学资料，男13例，女14例，中位年龄3岁。27例均进行了X线片、16层螺旋CT容积3D、标准和曲面多平面重组技术。结果 10例患者有分节异常，6例患者有形成异常，11例患者有复杂的、无法分类的畸形。15例肋骨畸形中，肋骨畸形的主要部分和脊柱旋转在同水平的有7例。8例合并脊髓纵裂，其中6例有完全或不完全的骨性隔。27例中的19例患者，多平面重组和3D图像显示出在常规X线片和常规轴面图像中未发现和认知的畸形并且全面评估了脊柱侧弯的程度，包括11例复杂畸形中7例归类为无法分类的脊柱畸形，4例为单侧未分节的骨桥合并同侧半椎体畸形；4例清晰显示出单侧未分节的骨桥（3例）和双侧骨桥融合（1例）；2例发现了掩蔽的半椎体畸形；2例重新评估了半椎体的类型和数目；27例曲面多平面重组图像更好的显示了椎管形态和脊髓弯曲情况，6例清晰显示椎管内骨性隔的生长方式和形态；4例患者标准多平面重组更好的显示了颅底-C1-C2的解剖和畸形，尤其是颅颈联合部畸形。结论 16层螺旋CT3D和标准或曲面多平面重组图像是诊断先天性脊柱侧弯、分析复杂多发或隐蔽脊柱和肋骨畸形的首选方法，在评价儿童脊柱侧弯的进展、修订手术方案较常规平片和（或）常规CT更具优势和指导意义。     

Imaging of painful scoliosis

Scoliosis is defined as a lateral deviation of the spine from the normal plumb line. Commonly, there is a rotational component and deviation also in the sagittal plane (kyphosis or hyperlordosis). When scoliosis presents in adults, it is often painful. In contrast, back pain in a child is considered rare, and serious underlying pathology should be excluded, particularly since idiopathic scoliosis is typically painless. A painful scoliosis in a child or adolescent, especially if the patient has a left-sided curve, should be examined thoroughly. The aim of this review is to illustrate the causes of a painful scoliosis in children, adolescents and adults.     

磁共振3D重建技术在脊柱侧弯中的应用

目的:探讨磁共振3D重建技术在脊柱侧弯中的应用价值。方法:对16例脊柱侧弯的患者,在磁共振扫描中,采用自旋回波T1WI及快速自旋回波T2WI序列,扫描完成后,将各序列分别进行3D重建,在1幅图像上显示整个脊柱及椎管内脊髓全貌。结果:16例均可在1幅图像上完整显示扭曲的脊柱及椎管内脊髓全貌,了解脊柱侧弯的程度,椎管内脊髓受压变形改变及脊髓内的病变和其完整的范围。结论:磁共振3D重建技术的应用,准确直观的诊断了脊柱畸形病变,对临床治疗和手术方案的制定有比较大的指导作用。