儿童急性白血病四肢骨关节的影像研究

Diagnostic imaging of limbs in children with acute leukemia

目的探讨急性白血病儿童患者四肢骨关节的X线和MRI特点。方法搜集以骨关节疼痛为主诉，经临床及骨髓穿刺确诊为急性白血病的13例患儿，对其疼痛部位均行X线平片检查，8例同时行MR检查，其中4例经过化疗达完全缓解后1周内行原疼痛部位的X线和MRI复查。对2种不同影像表现进行分析。结果13例中，6例X线表现正常，7例共14处可见骨质异常：干骺端透亮带5处，骨膜反应3处，混杂密度骨质破坏1处，浸润性骨质改变3处，骨质疏松2处。MR检查8例共11处，6例共9处MRI表现为骨髓浸润、坏死，X线表现正常；2例共2处MRI表现为骨髓浸润，X线可见骨膜反应及干骺端透亮带。4例化疗达完全缓解后1周内复查。MRI显示骨髓浸润、坏死病灶范围缩小并T1WI骨髓信号不均匀增高，坏死灶呈较均匀长T1.长T2信号，边界清晰，双边征消失，相同病例治疗前后X线复查未见明显改变。结论以骨关节痛为主诉的急性白血病患儿，MRI较X线能更早期、全面地检测到骨关节的病变，MRI可作为临床疗效监测的指标之一。

Objective To evaluate X-ray and MRI features of limbs in childhood acute leukemia. Methods Thirteen children with acute leukemia in our pediatric hematology ward were recruited. All patients were pathologically diagnosed by bone marrow aspiration and complained of bone or joint pain in the first visit. Conventional X-ray and MRI examinations of algesic sites were performed before clinical treatment and after complete remission. MR images were obtained with SE-T1WI, SE-T2WI and T2WI-fat suppressed sequences and symmetria bilateralis was requested while scanning. X-ray and MRI manifestations were evaluated and compared. Results All 13 patients had received X-ray examinations. Among them, 6 had normal X-ray findings, whereas the other 7 （14 sites） showed various abnormalities including radiolucent metaphyseal bands （5 sites） , periosteal reaction （3 sites） , osteapenia （2 sites） , mixed lesions （ lysissclerosis,1 site） , and permeative pattern （3 sites） . The number of patients for MRI examinations was 8 （11 sites）. Among them, 6 （9 sites） showed bone marrow infihration and bone marrow necrosis accompanied by normal X-ray findings, another 2 （2 sites） showed bone marrow infiltration associated with radiographic abnormalities of periosteal reaction and radiolucent metaphyseal bands. Four cases were followed up within 1 week when reached complete remission by chemotherapy. MR images features included reduced sizes of bone marrow infiltration lesions associated with increased signal intensity on Tl WI , and disappearance of double-line sign on bone marrow necrosis accompanied by signal homogenization. However, the radiograph before and after treatment in the same cases did not differ significantly. Conclusions MRI was earlier and more comprehensive in showing limbs bone marrow abnormality than radiogram in acute leukemia children with chief complaint of osteoarticular pains. MRI might be one of indicators in following up therapeutic effect for AL children with osteoarticular disorder.