一个75岁的男性,重达71公斤,在意外拔除肾造瘘术导管后,因与包膜下血肿有关的贫血入院。虽然患者表现出慢性肾病的进展,他还没有透析。他的血清肌酐水平上升到6.8毫克/分升,估计肾小球滤过率为7.4mL/min/1.73m2。放射科医生计划使用超低剂量造影剂进行对比增强的光子计数探测器CT(PCD-CT),以减轻对肾功能的影响。造影剂剂量设定为7.4gI,对于体重71公斤的男性,这比标准协议中使用的低82.6%。非对比增强的PCD-CT确定了肾包膜下血肿内的低密度结节区域。对比增强的PCD-CT显示对应于结节区域的早期和晚期的对比增强。在虚拟的单能量图像上,肾假性动脉瘤在40keV时最清楚。诊断为假性动脉瘤后,经导管动脉线圈栓塞术。没有观察到随后的贫血进展或肾功能恶化,展示了超低剂量对比增强PCD-CT用于检测小血管异常的潜力,同时将对肾功能的不利影响降至最低。
A 75-year-old male, weighing 71 kg, was admitted to our institution with anemia related to a subcapsular hematoma after accidental extraction of a nephrostomy catheter. While the patient exhibited the progression of chronic kidney disease, he was not yet on dialysis. His serum creatinine level increased to 6.8 mg/dL, with an estimated glomerular filtration rate of 7.4 mL/min/1.73 m2. Radiologists planned contrast-enhanced photon-counting detector CT (PCD-CT) with an ultra-low-dose contrast media to mitigate the impact on renal function. The contrast media dosage was set at 7.4 gI, which was 82.6% lower that used in the standard protocol for a male weighing 71 kg. Non-contrast-enhanced PCD-CT identified a low-density nodular area within the renal subcapsular hematoma. Contrast-enhanced PCD-CT revealed contrast enhancement in both the early and late phases corresponding to the nodular area. On virtual monoenergetic images, the renal pseudoaneurysm was most clearly delineated at 40 keV. Following the diagnosis of a pseudoaneurysm, transcatheter arterial coil embolization was performed. No subsequent progression of anemia or the deterioration of renal function was observed, showcasing the potential of ultra-low-dose contrast-enhanced PCD-CT for the detection of small vascular abnormalities while minimizing adverse effects on renal function.