CT测量成人骨性后颅凹狭窄的临床意义

The overcrowding of osteal posterior cranial fossa in adults： multi-slice CT measurements and clinical significance

目的探讨成人骨性后颅凹（PCF）狭窄的MSCT诊断标准与临床意义。方法采用MSCT及MPR、VR图像后处理技术，测量100名（男、女各50名）正常成人（对照组）和经MSCT检查及临床、手术证实的52例枕大孔区骨畸形患者（异常组）的PCF容积（PCFV）、PCF高径（PCFH）、斜坡长度（CL）、斜坡倾斜角（CG）、枕骨鳞部长度（SL）、枕大孔前后径（FMD），对其间的相关性和临床意义进行回顾性分析。对测量数据进行t检验。结果PCFV、PCFH、CL、SL、FMD、CG测量结果，对照组男性分别为（168．2±12．3）cm^3、（38．2±1．2）、（47．1±2．8）、（41．1±1．8）、（36．6±4．9）mm、（51．5±3．6）°，女性分另0为（157．5±10．2）cm^3、（36．5±1．4）、（46．2±2．2）、（39．7±1．3）、（35．2±3．8）mm、（49．6±3．1）°；异常组分别为（128．7±11．7）cm^3、（30．6±1．9）、（36．2±1．4）、（37．3±0．9）、（33．9±3．5）mm、（44．5±2．8）°。对照组内不同性别之间PCFV、PCFH、CL、SL、CG差异有统计学意义（t值分别为4．70、6．44、4．84、4．43、2．81，P值均〈0．01），各组间FMD差异无统计学意义（t=1．97，P〉0．05）；对照组男性与异常组PCFV、PCFH、CL、SL、CG差异有统计学意义（t值分别为16．62、24．04、25．01、14．17、10．99，P值均〈0．01）；对照组女性与异常组PCFV、PCFH、CL、SL、CG差异有统计学意义（t值分别为13．23、17．80、27．50、11．67、8．73，P值均〈0．01）；对照组男、女FMD与异常组比较差异无统计学意义（t值分别为2．96、2．07，P值均〉0．05）。结论MSCT可对PCF进行定量测量，作为术前常规检查有助于选择恰当的手术方式和PCF的应用解剖及其病理特征的研究。

Objective To assess the clinical value of MSCT in diagnosing the overcrowding of osteal posterior cranial fossa （PCF） in adults. Methods MSCT images of a cohort of 52 adult patients with foramen magnum osteal malformation confirmed by surgery （diseased group ）, and 100 healthy adults （control group） were retrospectively reviewed. Images post-processing techniques included muhi-planer reformation （MPR） and volume rendering （VR）. The posterior crania[ fossa volume （PCFV）, posterior cranial fossa height （PCFH）, elivus length （ CL）, elivus gradient （ CG）, supraoeeiput length （ SL）, and anteroposterior diameter of the foramen magnum （FMD） were measured on sagittal images in 52 patients and 100 normal adults. Independent-sample student＇s t test was used to compare the differences between patients and normal adults. Results The results of PCFV, PCFH, CL, SL, FMD and CG, male of control group were （168.2±12.3） cm3, （38.2±1.2）, （47.1 ＋2.8）, （41.1 ±1.8）, （36.6 ±4.9）mm, （51.5 ± 3.6）°, female of control group were （ 157.5 ± 10. 2 ） cm3, （36. 5 ± 1.4）, （46. 2 ± 2. 2 ）, （ 39.7 ± 1.3 ）, （35.2 ± 3.8） , （49. 6 ± 3.1 ） °; diseased group were （ 128. 7 ± 11.7 ） cm3, （30. 6 ± 1.9）, （ 36. 2 ± 1.4 ）, （37.3 ±0. 9）, （33.9 ±3.5）mm, （44. 5 ±2. 8）°. There was significant sex difference in PCFV, PCFH, CL, SL and CG in control group （ t= 4. 70, 6.44, 4. 84, 4. 43 and 2. 81 respectively, P 〈0. 01 ）, but FMD was not significant（ t = 1.97 ,P 〉 0. 05 ） ; the results of PCFV, PCFH, CL, CG and SL were significant different between diseased group and male of control group （t = 16. 62, 24. 04, 25.01, 14. 17 and 10. 99 respectively,P 〈 0. 01 ）; the results of PCFV, PCFH, CL, CG and SL were significant different between diseased group and female of control group （t = 13.23, 17.80, 27.50, 11.67 and 8.73 respectively,P 〈0. 01 ） ;but there were no significant differences of FMD between diseased group and control group, both male and female （ t = 2. 96,2. 07, P 〉0. 05）. Conclusions The overcrowding of PCF can be accurately measured by MCST. As a routine preoperative examination, MSCT is helpful in the therapeutic selection and the anatomic and pathologic study of PCF.