CAJ | 학술논문

目的：优化扫描方案，减少颅底伪影，改善图像质量。方法双排螺旋CT头颅平扫病例60例，随机分为3组，每组20例。 A、B组采用常规序列扫描，A组层厚为8 mm （4．0 mm ×2），B组层厚为4 mm（4．0 mm ×2）。 C组采用2段螺旋扫描程序，扫描参数为颅底3 mm （1．5 mm ×2）＋颅脑幕上5 mm（2．5 mm ×2）。观察和评价后、中颅窝图像有无伪影、伪影形态、位置、严重程度等。结果除A组1例外，A、B两组后颅窝均有不同程度的放射状伪影和交叉伪影，中颅窝部分病例有不同程度伪影。 B组Ⅱ级伪影的总数多于A组（29/16），Ш级伪影2例，显示B组4 mm层厚不能减轻颅底伪影，且有加重伪影程度的可能。 C组中部分病例后颅窝、中颅窝未见明显伪影，Ⅱ级伪影的例数为5例。与A、B组比较， C组可显著减轻颅底伪影，差异有统计学意义（P＜0．05）。结论颅底3 mm （1．5 mm ×2）＋颅脑幕上5 mm（2．5 mm ×2）螺旋扫描法，可显著减轻颅底伪影，改善图像质量，清晰显示颅底组织结构，具有临床应用价值。
목적：우화소묘방안，감소로저위영，개선도상질량。방법쌍배라선CT두로평소병례60례，수궤분위3조，매조20례。 A、B조채용상규서렬소묘，A조층후위8 mm （4．0 mm ×2），B조층후위4 mm（4．0 mm ×2）。 C조채용2단라선소묘정서，소묘삼수위로저3 mm （1．5 mm ×2）＋로뇌막상5 mm（2．5 mm ×2）。관찰화평개후、중로와도상유무위영、위영형태、위치、엄중정도등。결과제A조1예외，A、B량조후로와균유불동정도적방사상위영화교차위영，중로와부분병례유불동정도위영。 B조Ⅱ급위영적총수다우A조（29/16），Ш급위영2례，현시B조4 mm층후불능감경로저위영，차유가중위영정도적가능。 C조중부분병례후로와、중로와미견명현위영，Ⅱ급위영적례수위5례。여A、B조비교， C조가현저감경로저위영，차이유통계학의의（P＜0．05）。결론로저3 mm （1．5 mm ×2）＋로뇌막상5 mm（2．5 mm ×2）라선소묘법，가현저감경로저위영，개선도상질량，청석현시로저조직결구，구유림상응용개치。
Objective To optimize the scanning programs in order to reduce the skull base artifacts and improve images quality . Methods Sixty cases of brain performed with double helical CT were randomly divided into three groups with 20 in each.Group A and B u-sing routine sequential program ,the thickness was 8mm (4.0 mm ×2) in group A and was 4mm (4.0 mm ×2) in group B.Group C using two segments helical scan,the thickness for the base of the skull (Base) was 3mm (1.5 mm ×2),and for cerebrum (above brain curtain) was 5 mm (2.5 mm ×2).The artifacts shape,location,severity at posterior fossa,and middle cranial fossa images were observed and evalua-ted.Results In group A and B ,almost all cases had varying severity of radial and cross artifacts at posterior fossa ,and had different degrees of artifacts at middle cranial fossa in some cases .The total number of grade Ⅱartifacts in group B was more than that in group A (29/16). There were two cases of grade III artifacts in group B ,which showed that group B (4 mm thickness) did not reduce the skull base artifacts .In group C,some cases had no significant artifacts at posterior fossa and middle cranial fossa ,and 5 cases had grade Ⅱartifacts.Compared with group A and B,the artifacts of the skull base in group C could be significantly reduced ,and the difference was statistically significant ( P<0.05).Conclusion Base (1.5 mm ×2) +Cerebrum (2.5 mm ×2) helical scanning method can significantly reduce the artifacts of the skull base and improve image quality ,which clearly show the structure of the skull base .