弥散加权(DW)和血氧水平依赖性(BOLD)磁共振成像是功能性MR的经典序列,但是对非移植肾病的探索是有限的。
使用DW和BOLD成像分析肾小管间质性肾炎(TIN)的表观扩散系数(ADC)和R2*值的特征。
四种急性TIN,13名慢性TIN患者,并纳入4名对照.我们使用多个梯度回波序列来获取12个T2*加权图像以计算R2*图。DW成像通过组合单发自旋回波回波平面成像脉冲序列和沿x的附加运动探测梯度脉冲来获取ADC值,y,z轴具有两个b值:0和200,以及0和800s/mm2。ATIN患者在肾活检(T0)和第3个月(T3)进行DW和BOLD磁共振检查。我们半定量地评估了病理变化,并在功能MR中进行了相关性分析,病理和临床指标。
在ATIN,ADC显着降低(b为0,200s/mm2,2.86±0.19vs.3.39±0.11,b为0.800s/mm2,1.76±0.12vs.2.16±0.08,P<0.05)比对照组,在T3时表现出明显的缓解。皮质和髓质R2*值(CR2*,MR2*)下降,仅在MR2*中观察到显着差异(T024.3±2.1vs.T333.1±4.1,P<0.05)。未发现功能性MR与组织病理学指标之间的关系。MR2*与eGFR(R=0.682,P=0.001)、血肌酐(R=-0.502,P=0.012)密切相关。当b为0,200s/mm2时,ADC较低的患者治疗后ADC增加更多(R=-0.956,P=0.044)和MR2*(R=-0.949,P=0.05)。在CTIN组中,降低MR2*和MR2*/CR2*提供了肾内缺血的证据。具有晚期CKD(eGFR<45)的CTIN具有显著较低的ADCb200值。
我们观察到ATIN病例系列中ADC和R2*值的降低和缓解。ATIN患者的ADCb800和MR2*同时降低。CR2*在CTIN中具有持续低的MR2*的伪正常化表明肾内缺氧。
Diffusion-weighted (DW) and blood oxygen level-dependent (BOLD) magnetic resonance imaging are classical sequences of functional MR, but the exploration in non-transplanted kidney disease is limited.
To analyze the characteristics of apparent diffusion coefficient (ADC) and R2* value using DW and BOLD imaging in tubulointerstitial nephritis (TIN).
Four acute TIN, thirteen chronic TIN patients, and four controls were enrolled. We used multiple gradient-echo sequences to acquire 12 T2*-weighted images to calculate the R2* map. DW imaging acquired ADC values by combining a single-shot spin-echo echo-planar imaging pulse sequence and the additional motion probing gradient pulses along the x,y, z-axes with two b values:0 and 200, as well as 0 and 800 s/mm2. ATIN patients performed DW and BOLD magnetic resonance at renal biopsy(T0) and the third month(T3). We assessed the pathological changes semiquantitatively, and conducted correlation analyses within functional MR, pathological and clinical indexes.
In ATIN, ADCs were significantly lower(b was 0,200 s/mm2, 2.86 ± 0.19 vs. 3.39 ± 0.11, b was 0,800 s/mm2, 1.76 ± 0.12 vs. 2.16 ± 0.08, P < 0.05) than controls, showing an obvious remission at T3. Cortical and medullary R2* values (CR2*,MR2*) were decreased, significant difference was only observed in MR2*(T0 24.3 ± 2.1vs.T3 33.1 ± 4.1,P < 0.05). No relationship was found between functional MR and histopathological indexes.MR2* had a close relationship with eGFR (R = 0.682,P = 0.001) and serum creatinine(R = -0.502,P = 0.012). Patients with lower ADC when b was 0,200 s/mm2 showed more increase of ADC(R = -0.956,P = 0.044) and MR2*(R = -0.949,P = 0.05) after therapy. In CTIN group, lowered MR2* and MR2*/CR2* provided evidence of intrarenal ischemia. CTIN with advanced CKD (eGFR< 45) had significantly lower ADCb200 value.
We observed the reduction and remission of ADC and R2* values in ATIN case series. ATIN patients had concurrently decreased ADCb800 and MR2*. The pseudo normalization of CR2* with persistently low MR2* in CTIN suggested intrarenal hypoxia.