颅底粒细胞肉瘤MRI诊断(附3例报道)

目的提高对颅底粒细胞肉瘤的认识及诊断水平。方法报道3例发生于颅底的粒细胞肉瘤,详细分析了其临床症状、影像学表现,并复习相关文献。结果 3例粒细胞肉瘤均发生于急性髓细胞性白血病的儿童。其中2例以动眼神经麻痹为首发症状来诊,1例确诊为急性粒细胞白血病M2a型后出现头痛来就诊。影像上所有3例颅底骨骨髓信号异常,T_1WI信号减低,并出现髓外软组织肿块。其中1例肿块位于右侧上颌窦外侧壁和鞍旁。1例肿块浸润眼眶、海绵窦和动眼神经。1例广泛浸润脑膜、颅神经根和鼻窦,表现为多结节、多处软组织肿块。MR上所有肿块、结节T_1WI均为呈等信号,T_2WI上为稍低信号,增强扫描显著性强化。结论儿童颅底粒细胞肉瘤可以周围神经病变为首发症状,MRI上如颅底广泛弥漫性骨髓信号异常并出现单发或多发软组织结节或肿块应注意排除粒细胞肉瘤。

Imaging diagnosis of Granulocytic Sarcoma in the skull base

Objective To improve the understanding and imaging diagnosis of granulocytic sarcoma in the skull base. Methods Three cases of granulocytic sarcomas in the skull base are reported. The clinical features and imaging findings were analyzed. Results The three cases occurred in children with acute myeloid leukemia. Two patients presented with oculomotor paralysis before the diagnosis of leukemia, the third patient with history of leukemia presented with headache. Diffuse infiltration of basal skull bone marrow and extra- cranial soft tissue masses were shown on MRI. The signal intensities of the masses were similar to that of gray matter on TIWI and T2WI with marked contrast enhancement. The soft tissue masses were located in the para-sellar region and surrounded the lateral wall of the maxillary sinus in one ease. The soft tissue mass of the 2nd case infiltrated the orbital cavity, cavernous sinus and oculomotor nerve. Tumor infiltrating the meninges, cranial nerves and paranasal sinuses was seen in the 3rd patient. Conclusion Cranial nerve paralysis can be the presenting symptom of basal skull granulocytic sarcoma in children. Granulocytic sarcoma should be considered in the different diagnosis when diffuse abnormal signal intensities in the basal skull bone marrow with solitary or multiple soft tissue masses are shown on MRI.