Department of Urology, Northwestern University, Feinberg School of Medicine, 675 North St. Clair Street, Chicago, IL 60611, USA.
Urology. 2011 Mar;77(3):564-8. doi: 10.1016/j.urology.2010.06.056. Epub 2010 Dec 15.
To describe the natural history of postureteroscopic renal stone fragments ≤4 mm based on computed tomography (CT) follow-up. The goal of ureteroscopy is to fragment stones, actively basket and remove fragments larger than 1 mm, and allow the remaining fragments to pass spontaneously. The reality is that smaller fragments may be difficult to extract or may be missed.
Patients treated with ureteroscopy and holmium laser lithotripsy for urolithiasis by a single surgeon from May 2001 to July 2008 at a tertiary referral center were identified. Patients with residual renal fragments measuring ≤4 mm on initial postoperative CT and at least one additional follow-up CT were included. Outcomes measured were fragment growth and location, stone event (emergency department visit, hospitalization, or additional intervention), and spontaneous fragment passage.
Of 330 ureteroscopies, 51 met inclusion criteria. For these patients, the mean follow-up duration was 18.9 months (1.6 years). Among 46 ureteroscopies for calcium-based stones, 9 patients (19.6%) experienced a stone event, 10 patients (21.7%) spontaneously passed their fragments, and the remaining 27 patients (58.7%) retained asymptomatic residual fragments. Among this asymptomatic group, mean fragment sizes were similar at 2.7, 3.3, 3.5, and 3.0 mm at mean follow-up durations of 2.8, 10.2, 16.8, and 33.0 months, respectively.
This study suggests that among patients with postureteroscopic renal stone fragments ≤4 mm, approximately one in five (or 19.6%) will experience a stone event over the following 1.6 years. The remaining patients will either become stone-free via spontaneous passage or retain asymptomatic stable-sized fragments.
根据 CT 随访结果，描述后腹腔镜肾结石碎片≤4mm 的自然史。输尿管镜的目的是粉碎结石，积极篮筐和去除大于 1mm 的碎片，并允许剩余的碎片自发通过。但实际上，较小的碎片可能难以提取或可能被遗漏。
在一家三级转诊中心，我们确定了 2001 年 5 月至 2008 年 7 月期间由一位外科医生进行输尿管镜检查和钬激光碎石术治疗的尿石症患者。我们纳入了初始术后 CT 和至少一次额外随访 CT 上存在≤4mm 残留肾碎片的患者。我们测量的结果是碎片的生长和位置、结石事件（急诊就诊、住院或额外干预）和自发碎片通过。
在 330 例输尿管镜检查中，有 51 例符合纳入标准。对于这些患者，平均随访时间为 18.9 个月（1.6 年）。在 46 例钙结石的输尿管镜检查中，有 9 例（19.6%）出现结石事件，10 例（21.7%）自发排出结石碎片，其余 27 例（58.7%）残留无症状的残余结石碎片。在这个无症状组中，在平均随访时间分别为 2.8、10.2、16.8 和 33.0 个月时，平均碎片大小分别为 2.7、3.3、3.5 和 3.0mm。
本研究表明，在后腹腔镜肾结石碎片≤4mm 的患者中，约五分之一（或 19.6%）在接下来的 1.6 年内会出现结石事件。其余患者要么通过自发通过变为无结石状态，要么残留无症状的稳定大小碎片。
