Pulido Vega Diego, Motteau-Lévêque Mathieu, Maurey Christelle, Mortier Jeremy
Service of Diagnostic Imaging, École Nationale Vétérinaire d'Alfort, Maisons-Alfort, France.
École Nationale Vétérinaire d'Alfort, Maisons-Alfort, France.
J Vet Intern Med. 2025 Nov-Dec;39(6):e70252. doi: 10.1111/jvim.70252.
Identifying urolith mineral composition (UMC) is crucial for treatment and prevention; however, current data rely on macroscopic or ex vivo studies.
To describe in vivo radiographic characteristics of canine lower urinary tract (LUT) uroliths and identify discriminating radiographic features among UMC types.
Two hundred and two dogs with LUT uroliths composed of ≥ 70% calcium oxalate (n = 109), struvite (n = 58), or cystine (n = 35).
Retrospective cross-sectional study. Radiographs were evaluated for urolith size, shape, surface, borders, internal architecture, and quantitative radiopacity, and also assessed using a ratio of urolith-to-L5 vertebra pixel values (UOR). The diagnostic performance of urolith size and UOR was assessed with receiver operating characteristics (ROC) curves, calculating the area under the ROC curve (AUC).
Calcium oxalate uroliths were often highly radiopaque, associated with concurrent nephroliths, had unique shapes such as bosselated or spiculated, and less commonly ovoid. Struvite uroliths were larger (median: 15 mm; IQR: 8.1-25.8 mm) with a cut-off of ≥ 11 mm (AUC = 0.82, p < 0.001; specificity: 91%, sensitivity: 67%) and were associated with pyramidal shapes or solitary cystoliths. Cystine uroliths had lower radiopacity (median UOR: 0.71; IQR: 0.63-0.80), with a cut-off of UOR ≤ 0.83 (AUC = 0.81, p < 0.001; specificity: 67%, sensitivity: 84%).
In vivo radiographic characteristics such as size, shape, and radiopacity can help differentiate LUT mineral compositions, enabling non-invasive diagnosis and guiding treatment.
确定尿石矿物成分（UMC）对治疗和预防至关重要；然而，目前的数据依赖于宏观或体外研究。
描述犬下尿路（LUT）尿石的体内放射学特征，并确定UMC类型之间的鉴别放射学特征。
202只患有LUT尿石的犬，尿石中草酸钙含量≥70%（n = 109）、磷酸铵镁（n = 58）或胱氨酸（n = 35）。
回顾性横断面研究。对X线片评估尿石大小、形状、表面、边界、内部结构和定量不透X线性，并用尿石与L5椎体像素值之比（UOR）进行评估。用受试者操作特征（ROC）曲线评估尿石大小和UOR的诊断性能，计算ROC曲线下面积（AUC）。
草酸钙尿石通常高度不透X线，与并发肾结石有关，具有独特形状，如瘤状或有刺状，较少呈卵形。磷酸铵镁尿石较大（中位数：15 mm；四分位数间距：8.1 - 25.8 mm），截断值≥11 mm（AUC = 0.82，p < 0.001；特异性：91%，敏感性：67%），与棱锥形状或孤立性膀胱结石有关。胱氨酸尿石的不透X线性较低（UOR中位数：0.71；四分位数间距：0.63 - 0.80），截断值UOR≤0.83（AUC = 0.81，p < 0.001；特异性：67%，敏感性：84%）。
大小、形状和不透X线性等体内放射学特征有助于区分LUT矿物成分，实现非侵入性诊断并指导治疗。
