单通道经皮肾镜取石术术后结石残留因素分析及对策

目的 探讨影响单通道经皮肾镜碎石取石(PCNL)术后结石残留的因素.方法 对单通道PCNL术治疗84侧患肾的疗效进行分析,观察肾脏穿刺点选择,肾盂肾盏结构以及结石类型对手术成功率及结石清除率的影响.结果 ①84侧患肾中有83侧成功实施PCNL术,手术成功率98.8%.②在成功实施手术的患者中,单通道PCNL结石总清除率达到 84.34%(70/83).③Ⅱ期手术后肾大盏＞3组的结石总清除率为73.5%(25/34),肾大盏≤3组的结石清除率为87.8%(43/49),差异无统计学意义.④Ⅱ期手术后多发性肾结石的总清除率为86.2%(44/51),鹿角形结石为54.6%(6/11),单纯肾盂结石为100%(17/17),单纯肾盏结石为3/4,差异有统计学意义.结论 肾穿刺点选择及结石类型是影响单通道PCNL术成功率和结石清除率的重要因素,在考虑不同肾盏类型对结石清除率影响时必须同时结合结石的分布才有现实意义.术前通过仔细研究KUB、IVU等其他辅助检查,综合考虑肾盂肾盏结构以及结石类型因素,选择肾脏适宜的穿刺点是提高单通道PCNL术碎石取石效率的关键.     

输尿管软镜与经皮肾镜治疗一期经皮肾镜术后多发性残石的比较

目的比较输尿管软镜（RIRS）和经皮肾镜碎石取石术（PCNL）处理一期PCNL术后多发性残石的临床疗效。 方法回顾性分析2016年8月至2018年8月中山大学附属东华医院采用PCNL术后多发性残石78例患者的资料,其中男42例,女36例,平均年龄（46±13）岁,残石2～5个,单个结石直径≤2 cm。78例患者的操作均在一期手术后5～7 d肾造瘘管引流液变清后进行,根据残石的处理方案分为输尿管软镜组（R组）43例和经皮肾镜组（P组）35例,R组进行逆行输尿管软镜取石,P组在原经皮肾镜通道的基础上进行多通道PCNL。 结果所有操作均成功进行,无严重并发症发生,P组和R组的手术时间、结石清除率等差异无统计学意义;P组在平均血红蛋白浓度下降值（0.95±0.86 vs 0.29±0.45 g/dl）、住院时间（5.7±1.9 vs 1.8±1.5 d）和术后第1天疼痛视觉模拟评分（VAS） （5.1±1.1 vs 1.6±0.7）上显著高于R组（P<0.01）;P组和R组术后第1天血肌酐较术前升高值分别为（0.22±0.04）mg/dl和（0.07±0.01）mg/dl,（P<0.05）。 结论RIRS和PCNL处理PCNL术后多发性残石均是安全有效的,输尿管软镜对患者的的影响和术后恢复等方面具有一定的优势。     

Uric acid nephrolithias in the era of noncontrast computed tomography

We report 2 patients who presented with uric acid renal calculi. Both patients had previously been treated unsuccessfully for their stones with shock wave lithotripsy and were referred to our centre for percutaneous nephrolithomy. We were able to avoid surgery in both cases owing to the recognition of uric acid stone composition despite the calculi being visible on CT scout films.     

完全无管化与标准经皮肾镜治疗肾结石的Meta分析

目的系统评价完全无管化经皮肾镜碎石取石术(PCNL)与标准PCNL治疗肾结石的有效性和安全性。方法检索PubMed、Embase、Cochrane Library数据库。检索时限为从建库到2018年2月28日关于完全无管化PCNL和标准PCNL治疗肾结石的随机对照试验或回顾性病例对照试验,2名作者独立进行文献筛查和数据提取,运用RevMan 5.3软件进行Meta分析。结果共纳入5篇随机对照研究,2篇病例对照研究,共计781例患者,其中完全无管化PCNL组379例,标准PCNL组402例。Meta分析结果显示:完全无管化PCNL组的手术时间短于标准PCNL组(WMD:-2.72;95%CI:-4.05^-1.39;P<0.001);住院时间短于标准PCNL组(WMD:-1.48;95%CI:-1.84^-1.11;P<0.001);术后镇痛需求低于标准PCNL组(WMD:-6.91;95%CI:-9.00^-4.82;P<0.001);两组在结石清除率、术后血红蛋白丢失量及输血率方面差异均无统计学意义。结论完全无管化PCNL在治疗选择性肾结石患者方面优于标准PCNL,可以明显减少手术时间、住院时间和术后镇痛需求,而且不会增加手术相关的并发症。医师应根据患者的实际情况,个体化选择治疗方案。     

Clinical utility of computed tomography Hounsfield characterization for percutaneous nephrolithotomy: a cross-sectional study

Background

Computed Tomography (CT) is considered the gold-standard for the pre-operative evaluation of urolithiasis. However, no Hounsfield (HU) variable capable of differentiating stone types has been clearly identified. The aim of this study is to assess the predictive value of HU parameters on CT for determining stone composition and outcomes in percutaneous nephrolithotomy (PCNL).

Methods

Seventy seven consecutive cases of PCNL between 2011 and 2016 were divided into 4 groups: 40 (52%) calcium, 26 (34%) uric acid, 5 (6%) struvite and 6 (8%) cystine stones. All images were reviewed by a single urologist using abdomen/bone windows to evaluate: stone volume, core (HUC), periphery HU and their absolute difference. HU density (HUD) was defined as the ratio between mean HU and the stone’s largest diameter. ROC curves assessed the predictive power of HU for determining stone composition/stone-free rate (SFR).

Results

No differences were found based on the viewing window (abdomen vs bone). Struvite stones had values halfway between hyperdense (calcium) and low-density (cystine/uric acid) calculi for all parameters except HUD, which was the lowest. All HU variables for medium-high density stones were greater than low-density stones (p?<?0.001). HUC differentiated the two groups (cut-off 825 HU; specificity 90.6%, sensitivity 88.9%). HUD distinguished calcium from struvite (mean?±?SD 51?±?16 and 28?±?12 respectively; p?=?0.02) with high sensitivity (82.5%) and specificity (80%) at a cut-off of 35 HU/mm. Multivariate analysis revealed HUD?≥?38.5 HU/mm to be an independent predictor of SFR (OR?=?3.1, p?=?0.03). No relationship was found between HU values and complication rate.

Conclusions

HU parameters help predict stone composition to select patients for oral chemolysis. HUD is an independent predictor of residual fragments after PCNL and may be fundamental to categorize it, driving the imaging choice at follow-up.

     

Treatment for residual stones using flexible ureteroscopy and holmium laser lithotripsy after the management of complex calculi with single-tract percutaneous nephrolithotomy

This study validated the effectiveness and safety of the treatment for residual stones using flexible ureteroscopy (fURS) and holmium laser (0.6–1.2 J, 20–30 Hz) lithotripsy via a fiber with a 200-μm core diameter and 0.22 numerical aperture (NA) after the management of complex calculi with single-tract percutaneous nephrolithotomy (PCNL). Between January 2014 and June 2016, 27 consecutive patients with complex calculi underwent fURS and holmium laser lithotripsy after a planned single-tract PCNL. Among the 27 patients with complex calculi, 9 had full staghorn calculi, 7 had partial staghorn calculi, and 11 had multiple calculi. After the first single-tract PCNL session, the mean stone size and mean stone surface area were 18.0?±?10.7 mm and 181.9?±?172.2 mm², respectively. Treatment for residual stones with fURS and holmium laser lithotripsy was successfully completed and was performed without intraoperative complications. The mean operative time of the fURS procedure was 69.1?±?23.6 min, and the mean hospital stay was 5.3?±?2.4 days. The mean decrease in the hemoglobin level was 7.3?±?6.5 g/l. After the fURS procedure, the overall stone-free rate was 88.9%. The overall postoperative complication rate was 14.8% (Clavien grade I 11.1%; Clavien grade II 3.7%). The current approach tested here combines the advantages of both PCNL and fURS and effectively manages complex calculi with a high stone-free rate (SFR) (88.9%). This approach also reduced the number of treatment sessions, the number of percutaneous access tracts, and the blood loss and potential morbidity associated with multiple tracts.     

Planning percutaneous nephrolithotomy using multidetector computed tomography urography, multiplanar reconstruction and three-dimensional reformatting

OBJECTIVE: To assess a modified technique of multidetector computed tomographic urography (CTU) which can reproducibly and accurately map the pelvicalyceal system (PCS) and complex renal calculi, as such information is essential in choosing the optimal percutaneous approach into the PCS for safe and successful percutaneous nephrolithotomy (PCNL). PATIENTS AND METHODS: Ten consecutive patients with renal calculi underwent a modified four-detector multislice CTU with frusemide, abdominal compression and subsequent injection with contrast medium. After unenhanced CT of the abdomen, a high-resolution contrast-enhanced scan was taken through the kidneys in the pyelographic phase. Data were analysed using multiplanar reconstruction and three-dimensional (3D) reformatting. RESULTS: In 10 CTUs there were three staghorn, two diverticular, 25 calyceal, two infundibular and two renal pelvic calculi; nine showed posterior calyces and good infundibular anatomy, and provided a good map of the PCS. Seven patients had PCNL, with the remaining three having either primary extracorporeal shock wave lithotripsy or conservative management. CTU detected stones in all patients and accurately located their relation to the PCS. With reconstructed images, subjectively the 3D imaging provided an advantage over conventional imaging in optimizing nephrostomy placement. CONCLUSION: CTU with this protocol and post-processing techniques enables an accurate and confident, reproducible prediction of the site, number and size of stones in complex pelvicalyceal anatomy, optimal site(s) for placing the percutaneous track, and potential hazards when placing the track, with no significant increase in the patient's radiation burden. 3D CTU should become the standard imaging method for planning PCNL in selected patients.