闭合性脊柱裂的产前超声声像图特点

Spina bifida occulta in prenatal ultrasound scan

目的总结闭合性脊柱裂的产前超声声像图特点．以提高此类脊柱裂的诊断水平。方法2014年1月至2015年4月，大连市妇幼保健院超声科检查诊断的胎儿闭合性脊柱裂孕妇16例，纳入分析。16例均为单胎妊娠，均在常规产前超声胎儿脊柱检查中发现疑问，并重点观察胎儿脊柱情况及脊髓圆锥的位置从而得到诊断。描述性分析闭合性脊柱裂胎儿的超声声像图特点。结果16例胎儿中12例皮肤下方可见外凸包块，呈小囊样无回声者9例，呈强回声团3例；另外4例无包块，表现为脊柱生理弯曲消失，排列紊乱，成角或侧弯，或者病变两侧脊柱的骨化中心不对称，脊髓圆锥位置低。15例无颅脑征象改变，另1例可见“柠檬头”及“香蕉小脑”。8例伴有脊髓栓系，6例脊髓圆锥位置显示不清，2例圆锥位置正常。16例均经MRI或尸体解剖或新生儿手术证实诊断正确。结论产前超声检查发现胎儿脊柱或脊髓圆锥位置异常时，应高度可疑闭合性脊柱裂并进行多切面联合扫查．

Objectives To summarize and analyze the characteristics ofspina bifida occulta in prenatal ultrasound scan in order to improve the accuracy of diagnosis. Methods Sixteen singleton pregnant women with fetal spina bifida oceulta who were diagnosed in the Ultrasonography Department of Dalian Maternal and Child Health Hospital from January 2014 to April 2015, were enrolled in this study. Diagnosis was made based upon the abnormalities found in the spinal column of fetus during routine ultrasound scan, followed by a close examination on the fetal spinal column and the position of conus medullaris by using multiple scan. Descriptive analysis was used to summarize the characteristics of spina bifida occulta in ultrasonic images. Results Among the 16 cases, 12 had subcutaneous mass （nine cases had follicle like anechoic mass and three cases had masses with strong echoes）. The other four cases without subcutaneous mass manifested signs of disappeared physiological curvatures or disordered arrangement of spinal column, angulation deformity or scoliosis, or asymmetry in ossification centers of spinal column on both sides of lesions and lowered position of eonus medullaris. ＂Lemon shaped head＂ and ＂banana shaped cerebellum＂ were seen in one case, while the other 15 cases were found no cerebral abnormalities. Eight cases had tethered cord （the position of conus medullaris was lower than the second lumber vertebra）, six cases had unclear position of conus medullaris and the other two were normal. Diagnoses for all of the 16 cases were confirmed by MRI after delivery or autopsy or neonatal operation. Conclusions Abnormalities such as subcutaneous mass and tethered cord observed in prenatal ultrasound scan are significant indicators for suspected closed spinal dysraphism and further multiple scan is required to confirm the diagnosis.