螺旋CT及三维重建尿路成像在肾发育不良诊断中的应用

目的 寻觅诊断小儿肾发育不良最好的检查方法。方法 对7例正常排尿的间歇期有会阴部滴尿的患儿，均经超声、单光子发射计算机断层肾动态显像（SPECT）、静脉尿路造影、（IVU）和CT尿路成像（CTU）检查。并对照术后诊断，比较CTU、IVU、超声、SPECT对肾发育不良的诊断符合率。结果 7例患儿的发育不良肾CTU均清楚显示，左侧3例，右侧4例。增强后实质期图像示病变侧腰大肌前方明显强化的肾样小结节，分泌期图像可显示集合系统及输尿管腔，MPR、3D、4D像直观、立体，显示了发育不良肾的大小、位置、轮廓及其输尿管走行。CTU诊断符合率100％。ECT检查仅1例显示发育不良肾，诊断符合率14.3%(1/7)。IVU、B超均未能显示发育的肾和输尿管。CTU的诊断符合率明显高于SPECT、IVU及B超。结论 如疑有肾发育不良或经超声初步检查仅发现一个肾，应行CTU检查，以明确是否为单侧肾发育不良。CTU是目前诊断肾发育不良最准确的非创伤性影像检查方法。     

离断性肾盂成形术治疗先天性肾盂输尿管连接部梗阻

先天性肾盂输尿管连接部梗阻（UPJO）所致肾积水是小儿较常见的泌尿系畸形，发病原因包括肾盂输尿管连接部狭窄、瓣膜、息肉、高位输尿管口、迷走血管或副血管压迫等。临床症状无特异性，主要依靠影像学诊断，B超检查简便易行，可作为UPJO的初步筛选诊断。静脉尿路造影通过肾脏对特殊造影剂的摄取和经上尿路的排泄，     

儿童肾积水的影像学诊断策略

儿童肾积水最常见的病因是肾盂输尿管连接部(uteropelvic junction,UPJ)狭窄,表现为肾盂肾盏扩张积水。临床上对儿童肾积水的诊断依赖于超声、静脉肾盂造影(intravenous pyelography,IVP)、MR尿路成像(MR urography,MRU)、CT尿路成像(CT urography,CTU)、核素扫描(SPECT肾动态扫描)等多种影像学检查。不同医疗机构设备和技术不尽相同,目前诊断儿童肾积水主要有超声+IVP+MRU、超声+CTU、超声+SPECT+MRU等几种影像学检查组合。本文就儿童肾积水各种影像学诊断方法的优缺点及最佳组合方式进行解读。     

CT尿路减影对小儿泌尿外科疾病诊断的意义

ＣＴ尿路造影 (ＣＴＵ)是近年来泌尿系影像诊断领域中继静脉尿路造影(ＩＶＵ)及超声之后又兴起的一项新的检查技术 ,它具有较高的分辨率 ,对术前患肾形态、肾实质厚度、肾功能、肾积水程度、输尿管是否扩张、判定梗阻部位、性质及是否合并其他畸形等方面都能做出正确评估 ,我院从 1 997年 3月～ 2 0 0 1年 1月对ＩＶＵ检查患肾不显影、ＩＶＵ及超声均不能做出明确诊断的部分病例采用ＣＴＵ方法 ,取得较满意的效果。现报道如下。资料与方法1 .临床资料　本组 2 4例 ,男 1 8例 ,女 6例 ,年龄 1 5ｄ～ 7岁。先天性重度肾积水 1 5例 ,先天性巨输…     

CT尿路造影对小儿泌尿外科疾病诊断的意义

CT尿路造影(CTU)是近年来泌尿系影像诊断领域中继静脉尿路造影(IVU)及超声之后又兴起的一项新的检查技术,它具有较高的分辨率,对术前患肾形态、肾实质厚度、肾功能、肾积水程度、输尿管是否扩张、判定梗阻部位、性质及是否合并其他畸形等方面都能做出正确评估,我院从1997年3月～2001年1月对IVU检查患肾不显影、IVU及超声均不能做出明确诊断的部分病例采用CTU方法,取得较满意的效果.现报道如下.     

MSCTU在小儿先天性上尿路畸形的诊断价值

对于泌尿系统疾病的影像学诊断CT一直占有非常重要的地位,传统诊断方法B型超声、X线、排泄性静脉尿路造影及逆行尿路造影等对小儿复杂泌尿系畸形的解剖形态、泌尿系功能及病因学诊断上存在很大局限性,其发现泌尿系统病变往往需要CT检查以获得确定性诊断,为手术方案的制定提供帮助.     

脊髓栓系合并上尿路损害的治疗决策

目的：探讨脊髓栓系合并上尿路损害的治疗策略。方法：1997年7月～2002年3月共收治合并上尿路损害的脊髓栓系综合征42例，男26例，女16例，年龄2～16岁，平均6．7岁。根据上尿路损害的程度分为两组：A组(严重组)26例，B组(轻组)16例，常规先行栓系松解术，其中10例术后上尿路损害加重。对36例上尿路损害严重患儿先后行膀胱功能重建术。27例获得随访．随访时间6～33个月，平均25个月。评价方法：手术前后行尿动力学、影像学及血生化检查。尿动力学评价采用配对资料t检验。结果：术前上尿路损害：静脉肾盂造影双侧不显影伴BUN略高1例，单侧不显影1例，中等以上肾盂积水11例，Ⅳ度以上膀胱输尿管反流14例。术后：静脉肾盂造影不显影者分别于1h、1．5h延时显影。肾盂积水减轻7例，4例无明显变化。输尿管反流消失7例，减轻6例，1例无变化。总有效率81．48％。膀胱容量、膀胱顺应性较术前提高，逼尿肌漏尿压较术前降低。结论：脊髓栓系合并严重上尿路损害时应先行膀胱功能重建术。对损害轻者常规先行栓系松解术。膀胱功能重建术可有效降低膀胱内压，避免上尿路损害进一步加重。     

先天性肾盂输尿管连接处梗阻的诊断和治疗

目的 探讨先天性肾盂输尿管连接处梗阻(UPJO)致肾积水的诊断和治疗方法.方法 回顾分析UPJO致肾积水患儿63例的临床资料.患儿均经彩超筛查、静脉肾盂造影(IVP)、磁共振尿路成像(MRU)或电子计算机X射线断层扫描尿路成像(CTU)确诊.单侧肾积水55例中47例行一期离断式肾盂输尿管成形术,切除无蠕动功能的肾盂输尿管狭窄段和大部分扩张的肾盂;5例因重度肾积水先行患肾穿刺造瘘引流3～6个月,其中3例二期行离断性肾盂成形术,另2例因肾脏无功能行肾切除术;3例保守治疗.双侧肾积水8例中3例一期完成双侧肾盂输尿管成形术,5例分次完成.结果 术后B超随访,肾积水均有改善,肾盂前后径缩小,肾实质增厚;IVP均证实肾盂输尿管吻合口通畅.肾脏积水导致肾功能受损者,术后肾动态显像榆查患肾功能均有恢复.结论 彩超为UPJO诊断最常用的筛查方法,IVU、MRU及CTU是确诊UPJO的可靠方法,先天性肾盂输尿管连接部狭窄是造成肾积水的首要原因、肾盂进行性扩张或肾功能损害进行性加重者需行离断性肾盂成形术.     

利尿性肾图在小儿肾盂输尿管连接部梗阻致肾积水诊断中的作用

目的探讨以利尿性肾图替代静脉尿路造影对小儿肾盂输尿管连接部梗阻引起的肾积水进行诊断的可能性.方法对1995年8月至2001年10月间的52例同时行静脉尿路造影和利尿性肾图检查并进行了肾盂成形术的病例进行回顾性分析,男47例,女5例,年龄0.2～13岁(平均6.5岁).结果本组52例静脉尿路造影对梗阻部位判断有52例(100%)正确;利尿性肾图检查后,52例患儿梗阻部位的判断也都(100%)正确.静脉尿路造影和利尿性肾图在梗阻部位诊断上差异没有显著性意义(P＞0.05).结论在诊断小儿肾盂输尿管连接部梗阻上,以利尿性肾图来替代静脉尿路造影是可行的.     

磁共振尿路成像技术在诊断新生儿先天性肾盂输尿管连接部梗阻中的应用

目的探讨磁共振尿路成像(MRU)技术在诊断新生儿先天性肾盂输尿管连接部梗阻(CUJO)中的应用价值。方法回顾性分析2010—2011年在我院行MRU检查的新生儿影像资料及手术结局。MRU检查序列包括3D尿路成像、常规轴位快速恢复快速自旋回波T2WI和稳态采集快速成像。所有图像在AW4.2工作站经最大密度投影、容积再现和Reformat重建出3DMRU图像。结果共21例患儿行MRU检查,均为孕期B超发现胎儿肾积水、出生后复查B超肾积水加重或临床症状加重就诊。MRU诊断双肾积水1例,右肾积水伴肾盂输尿管移行部狭窄7例,左肾积水伴肾盂输尿管移行部狭窄13例。21例患儿均接受手术治疗,其中腹腔镜下左肾盂成形术加膀胱镜探查术13例,右肾盂成形术加膀胱镜探查术6例,经脐单孔腹腔镜右肾输尿管切除术1例,双肾盂成形术加膀胱镜探查术1例。术后诊断均与MRU诊断相符。结论 MRU技术因具有无射线损伤、多角度、多方位、多参数成像等特点,已成为新生儿CUJO诊断、鉴别诊断及外科手术方案制定中不可缺少的重要检查手段,具有良好的发展前景。     

Combined static-dynamic MR urography for the simultaneous evaluation of morphology and function in urinary tract obstruction

PURPOSE: To assess the diagnostic value of combined static-dynamic MR urography (MRU) for the functional-morphological evaluation of experimentally induced urinary tract obstruction in the piglet. MATERIALS AND METHODS: In 20 piglets unilateral ureteric stenosis was created operatively. Post-surgery repeated comparative examinations were obtained with MRU, diuretic renal scintigraphy (DRS), excretory urography (EU) and ultrasound (US). MRU was performed as a combination study with a static 3D-IR-TSE sequence and a dynamic 2D-FFE sequence after Gd-DTPA with frusemide administration. RESULTS: MRU allowed complete depiction of the prestenotic urinary tract and of the stenosis in all cases. In 43 comparative studies MRU was superior to EU in 36, EU to MRU in 2. When single kidney function was calculated with both MRU and DRS, results were highly correlated (r = 0.92). When urinary excretion was compared, significant agreement was achieved with concordant findings in 86% and slightly discordant results in 12%. CONCLUSIONS: Static-dynamic MR urography permits excellent depiction of experimentally induced urinary tract obstruction in piglets and reliable assessment of individual renal function and urinary excretion. Two advantages of the method stand out--it does not require radiation and it permits functional-morphological correlation.     

Combined static-dynamic MR urography for the simultaneous evaluation of morphology and function in urinary tract obstruction

Objective. A new approach, combined static-dynamic MR urography is evaluated to determine its potential utility for the functional-morphological diagnosis of paediatric urinary tract obstruction. In this initial investigation we sought to evaluate the procedure by imaging the urinary tract of piglets. Materials and methods. Twenty-nine healthy piglets were studied with MR urography (MRU), ^{99 m}Tc-MAG3 diuretic renal scintigraphy (DRS), ultrasound (US) and excretory urography (EU). The functional and morphological findings were compared. For MRU we combined a respiration-triggered 3D-IR-TSE sequence and a dynamic 2D-FFE sequence after Gd-DTPA injection. Results. MRU depicted the complete urinary tract with superior image quality compared to EU. Calculation of time-intensity curves from the dynamic sequence permitted determination of single kidney function from parenchymal ROIs and urinary excretion using the whole kidney ROI. MRU and DRS showed significant agreement in the assessment of both single kidney function and urinary excretion. Disturbances of urinary drainage were generally caused by an overfilled bladder. Conclusions. Combined static-dynamic MRU is well suited for the depiction of the complete urinary tract and for the determination of individual kidney function and urinary excretion in the piglet. Received: 21 February 2000 Accepted: 14 March 2000     

Application of magnetic resonance urography in diagnosis of congenital urogenital anomalies in children

Magnetic resonance urography (MRU) has become a useful adjuvant in evaluating urogenital anomalies. In present study, we evaluated the ability of MRU in diagnosis of different congenital urogenital anomalies when the results of conventional imaging modalities were inconclusive. A total of 90 children were included in this series. The children were evaluated with T2-weighted and contrast-enhanced T1-weighted MRU sequences. The results were compared with findings obtained with ultrasonography, intravenous urography, renal nuclide scan, and voiding cystourethrography. MRU was requested in these children because conventional imaging modalities were equivocal or a co-existing urogenital anomaly was suspected. Only those cases that underwent surgery were included in this study and the surgical findings were set as the reference standard in statistical evaluation. The records of 61 boys with mean (range) age of 2.3 years (2 months-12 years) and 29 girls with mean (range) age of 3.3 years (3 months-12 years) were reviewed. The final diagnosis was ureteropelvic junction obstruction (n = 25), vesicoureteral junction obstruction (n = 16), ureterocele (n = 19), ectopic kidney (n = 11), posterior urethral valve (n = 17), and polycystic kidney (n = 2). The overall sensitivity of MRU, intravenous urography, renal nuclide scan, ultrasonography, and voiding cystourethrography in diagnosis of the aforementioned anomalies were 86, 63, 50, 44, and 41%, respectively. MRU was much more sensitive than other imaging modalities in diagnosis of end-ureteral dilation (100%) and ureterocele (89%). MRU provides a reliable noninvasive technique for imaging of the congenital anomalies in the urinary tract of children with T2-weighted MRU sequences providing unenhanced static-water images of the urinary tract as well as depicting adjacent soft-tissue lesions, and T1-weighted MRU technique imitating conventional intravenous urography. Both MRU sequences can be combined for a comprehensive examination of the urinary tract.     

Comparison Between Diuretic Urography (IVP) and Diuretic Renography for Diagnosis of Ureteropelvic Junction Obstruction in Children

Background:

Ureteropelvic junction obstruction (UPJO) is one of the most common causes of urinary tract obstruction in children. Several methods are used to diagnose upper urinary tract obstruction including renal ultrasonography (US), intravenous pyelogram (IVP), diuretic renography (DR), magnetic resonance urography (MRU) and antegrade or retrograde pyelography. Nowadays it is suggested to use diuretic renography as the best method for diagnosing of UPJO. There is no comparative study between IVP and DR scan for diagnosis of UPJO in children.

Objectives:

The aim of the present study was to compare IVP with furosemide injection and diuretic renography in diagnosis of clinically significant UPJO.

Patients and Methods:

This was a cross sectional study performed in 153 UPJO suspected children (121 boys, 32 girls) based on US findings in cases presented with urinary tract infection (UTI), prenatal hydronephrosis, abdominal/flank pain, abdominal mass and hematuria. Renal ultrasound was used as an initial screening tool for detection of urinary tract abnormality. Vesicoureteral reflux (VUR) was ruled out by voiding cystourethrography (VCUG). Serum creatinin, blood urea nitrogen, urinalysis and urine culture was screened in all cases. IVP with furosemide and DR were performed as soon as possible after the mentioned workup.

Results:

During a five year period, 46 out of 153 patients were diagnosed as UPJO based on diuretic renography: the age ranged from 4 months to 13 years (mean: 3.1 ± 0.78 years). There was a significant higher (76%) proportion of UPJO in the boys and in the left side (78%). The sensitivity of IVP with furosemide injection in diagnosis of UPJO was 91.3% whereas DR was accepted as standard for diagnostic procedure in diagnosis of UPJO.

Conclusions:

Although DR is accepted as the best method for diagnosis of UPJO, we found a small sensitivity difference between IVP and DR in kidneys with normal or near normal function. In many settings such as small cities lacking facilities for advanced isotope imaging technology, use of IVP with diuretic maybe an acceptable procedure for diagnosis of UPJO.     

Magnetic resonance urography for diagnosis of pediatric ureteral stricture

PurposeUreteral stricture is a rare cause of hydronephrosis in children and is often misdiagnosed on ultrasound (US) and diuretic renal scintigraphy (DRS), requiring intraoperative diagnosis. We evaluated ureteral strictures diagnosed by magnetic resonance urography (MRU) at our institution.Materials and methodsChildren with ureteral stricture who underwent MRU were identified. Patient demographics, prior imaging, MRU findings, and management were assessed. The efficacy of MRU in diagnosis of stricture was compared with US and DRS. Patients with ureteropelvic or ureterovesical junction obstruction were excluded.ResultsTwenty-eight ureteral strictures diagnosed by MRU between 2003 and 2013 were identified; 22% of strictures were diagnosed by DRS ± US. The mean age at MRU diagnosis was 2.4 years (range 4 weeks–15 years). Hydronephrosis was the most common presentation, accounting for 20 (71%) cases. Other etiologies included pain (3), incontinence (2), and urinary tract infection, cystic kidney, and absent kidney, present in one case each. A mean of 2.7 imaging studies was obtained prior to MRU diagnosis. Twenty-one (75%) ureteral strictures required surgical intervention, with the approach dependent upon location.ConclusionsMRU provides excellent anatomic and functional detail of the collecting system, leading to accurate diagnosis and management of ureteral stricture in children.     

MR imaging of kidneys: functional evaluation using F-15 perfusion imaging

BACKGROUND: Children with hydronephrosis are typically investigated by a combination of diuretic renal scintigraphy, ultrasound, and voiding cystourethrography. Unfortunately, there is no gold standard to assess obstruction. PURPOSE: The purpose of our study was to evaluate the utility of dynamic contrast enhanced MR urography in the investigation of children with hydronephrosis to define urinary tract anatomy, to calculate differential renal function and to assess urinary tract obstruction. MATERIALS AND METHODS: Dynamic contrast-enhanced MR imaging was performed in 40 children with unilateral hydronephrosis. There were 14 girls and 26 boys with an age range of 1 month to 14 years (mean 1.4 years). The information from traditional imaging modalities was compared to the information obtained from the single MR study. RESULTS: The anatomic imaging with MR urography was superior to other modalities. The split renal function was estimated with MR urography by calculating the volume of enhancing renal parenchyma and was comparable to renal scintigraphy ( r=0.98). By using surgery versus non-surgery as the decision point, with MR urography the sensitivity was 100%, specificity 71%, positive predictive value 86%, negative predictive value 100%, and diagnostic efficiency 90%. For renal scintigraphy the sensitivity was 96%, the specificity 56%, positive predictive value 76%, negative predictive value 90%, and diagnostic efficiency 79%. CONCLUSIONS: Dynamic contrast-enhanced MR urography provides superior anatomic and functional information when compared with ultrasound and diuretic renal scintigraphy. The information is gathered in a single study that does not use ionizing radiation. It is likely that MR urography will replace renal scintigraphy in the evaluation of hydronephrosis in children.     

Single-system ectopic ureters associated with renal dysplasia

The purpose of this study was to inquire into the clinical features and methods for the diagnosis and therapy of single-system ectopic ureters associated with renal dysplasia. Intravenous urography (IVP), diuretic B-mode ultrasound (B-US), and, in four cases, computerized tomography (CT) were performed in twelve female patients with renal dysplasia-seven on the left and five on the right-and the clinical records were retrospectively summarized and analyzed. The main presentation was droplet urinary incontinence. IVP and B-US showed that in all in whom the affected kidneys did not function, the contralateral kidneys had undergone compensatory hypertrophy. Only in four cases were the dysplastic renal tissues displayed in the pelvic cavity on B-US. In eight cases, the affected kidneys were not found. Of the four patients who had CT scanning, the dysplastic kidneys were explored in the pelvis in two cases. All patients underwent ureteronephrectomy, and the urinary incontinence disappeared after operation. Single-system ectopic ureters associated with renal dysplasia mainly affect female children, and most present with droplet urinary incontinence; the affected kidney may not be displayed on ultrasonography and IVP, but the contralateral kidney may display compensatory hypertrophy on IVP and can easily be misdiagnosed as a solitary kidney. The curative effect of ureteronephrectomy is definite.     

磁共振尿路造影诊断小儿上尿路梗阻

目的：探讨磁共振尿路造影（MRU）诊断上儿上尿路梗阻的价值。方法：27例上尿路梗阻患儿术前作IVU、BUS和MRU检查,MRU应用重T2加权脂肪抑制快速自旋回波序列。对照分析MRU影像与手术结果,比较MRU与IVU、BUS在上尿路梗阻定位定性诊断中的作用。结果：MRU诊断肾盂输 尿管连接部狭窄12例,重肾双输尿管畸形3例,原发性巨输尿管症7例,输尿管膀胱入口狭窄5例。MRU影像与手术结果完全一致,对上尿路梗阻的定位定性诊断正确率100％（27／27）。结论：MRU是诊断小儿上尿路梗阻的理想手段。     

MR urography: the future gold standard in paediatric urogenital imaging?

Background. Examination of the paediatric urogenital tract is traditionally performed using methods that utilise ionising radiation, such as intravenous urography (IVU), computerised tomography (CT), voiding cystourethrography (VCU), and scintigraphy, in addition to ultrasound (US). Objective. To determine the potential and effectiveness of MR urography (MRU) in infants and children. Materials and methods. 44 MRU examinations were prospectively performed in 39 patients (21 infants, mean age 3.5 months, and 18 children, mean age 6 years 2 months) with known or suspected pathology of the urinary tract. Non-enhanced, fast spin-echo sequences (TSE) were performed in all patients. In 70 % of the patients a contrast-enhanced, fast gradient-echo sequence (TFE) was included. The dynamic sequence was prolonged and supplemented with furosemide provocation in some patients with suspected urinary-tract obstruction. Results. Nine percent of examinations were non-diagnostic or interrupted due to movement. MRU contributed additional information in 66 %. Nine patients with suspected urinary-tract obstruction were examined with both contrast-enhanced MRU and scintigraphy. Three MRU examinations were less informative and one equal to scintigraphy when obstruction was the diagnosis. When using a technique with a prolonged dynamic sequence, including frusemide provocation, four MRU examinations were equal and one was superior to scintigraphy. Conclusions. MRU has the potential to replace traditional diagnostic methods which use ionising radiation in paediatric patients. Further studies are needed before definite conclusions can be drawn. Received: 18 June 1998 Accepted: 9 March 1999