Department of Surgical Sciences, Radiology Institute, University of Turin, Via Genova 3, 10126, Turin, Italy.
SCDU Nephrology, Città della Salute e della Scienza, University of Turin, Turin, Italy.
Abdom Radiol (NY). 2018 Mar;43(3):639-646. doi: 10.1007/s00261-017-1242-0.
To analyze with diffusion-weighted magnetic resonance imaging (DW-MRI) the evolution and progress to resolution of acute pyelonephritis (APN) foci over a period of 3 months after onset.
30 women (age 22-51 years) with clinical, laboratory (white blood cell and C-reactive protein), and DW-MRI (4b-values 0, 50, 600, 1000 s/mm) diagnosis of APN were prospectively enrolled. Two double-blinded radiologists evaluated the number of APN foci, and for each of them dimension (D), absolute diffusion coefficient (ADC), and its ratio R to the ADC of unaffected parenchyma. Signature of radiological recovery was focus no longer visible (DW-) and ADC of its site not inferior to the ADC of the unaffected parenchyma, i.e., R ≥ 0.9. Clinical and DW-MRI follow-ups (FU) were performed at 1 and 3 months.
At the acute stage (t ), 187 APN foci were found, with ADC = 1.3 ± 0.2 × 10 mm/s, R = 0.65 ± 0.12, and D = 14 ± 7.5 mm. By the 1-month FU (t ), all patients had no symptoms and physiological laboratory values; despite this, only 80 (43%) foci were solved, increasing to 138 (74%) by at the 3-month FU. The ROC curve (AUC ≥ 0.80) identified R ≤ 0.6 and D > 15 mm as forecast of slow radiologic resolution. About 80% of foci unsolved at 1 month but with R ≥ 0.8 and D ≤ 10 mm reached solution at 3 months.
DW-MRI recovery of APN foci does not always coincide with clinical recovery. The evolution of an APN focus is shaped by its initial values R and D . About half of the foci still visible at 1 month reached radiological resolution in the two following months.
通过弥散加权磁共振成像（DW-MRI）分析急性肾盂肾炎（APN）发病后 3 个月内焦点的演变和消退情况。
前瞻性纳入 30 名年龄在 22-51 岁之间、有临床、实验室（白细胞和 C 反应蛋白）和 DW-MRI（4b 值为 0、50、600、1000s/mm2）诊断为 APN 的女性患者。两名双盲放射科医生评估了 APN 病灶的数量，为每个病灶评估了尺寸（D）、绝对扩散系数（ADC）及其与正常组织 ADC 的比值 R。放射学恢复的特征是病灶不再可见（DW-），且其部位的 ADC 不低于正常组织的 ADC，即 R≥0.9。在 1 个月和 3 个月时进行临床和 DW-MRI 随访（FU）。
在急性期（t）时，共发现 187 个 APN 病灶，ADC=1.3±0.2×10mm/s，R=0.65±0.12，D=14±7.5mm。在 1 个月 FU（t）时，所有患者均无症状，生理实验室值正常；尽管如此，只有 80（43%）个病灶得到解决，在 3 个月 FU 时增加到 138（74%）。ROC 曲线（AUC≥0.80）确定 R≤0.6 和 D＞15mm 为放射学恢复缓慢的预测因素。约 80%在 1 个月时未解决但 R≥0.8 且 D≤10mm 的病灶在 3 个月时得到解决。
APN 病灶的 DW-MRI 恢复并不总是与临床恢复一致。APN 病灶的演变由其初始值 R 和 D 决定。大约一半在 1 个月时仍可见的病灶在随后的两个月内达到了放射学缓解。
