title: Sonographic measurement of cervical volume in nonpregnant women using the geometric formula for a cylinder versus the three-dimensional automated virtual organ computer-aided analysis (vocal).
abstract: BACKGROUND
  To sonographically evaluate the volume of uterine cervix in nonpregnant women with use of the geometric formula for a cylinder and to assess agreement with the reference Virtual Organ Computer-Aided AnaLysis (VOCAL) method.
  
  
  METHODS
  Three-dimensional ultrasound volume datasets of the uterine cervix from 81 women were obtained prospectively within a 1-year period. Volume measurements were performed using VOCAL and the geometric formula for a cylinder. Reliability was evaluated using intraclass correlation coefficient and Bland-Altman plots were produced to examine intermethod agreement. Time needed to perform measurements was compared with Student's t test.
  
  
  RESULTS
  There was good agreement between VOCAL and the geometric formula for a cylinder (mean percentage difference, -0.78%; 95% limits of agreement, -17.59-16.03%). Measurements made by the formula for a cylinder were slightly greater than VOCAL by a mean (±SE) of 0.78% (±0.95%). A high degree of reliability was observed between the two methods (intraclass correlation coefficient, 0.97; 95%CI, 0.95-0.98). Cervical volume estimation with the geometric formula for a cylinder was faster to obtain.
  
  
  CONCLUSIONS
  This method comparison study shows that the geometric formula for a cylinder has good agreement with VOCAL and can determine the volume of the cervix in a faster way.
authors.affiliation: First Department of Obstetrics and Gynecology, University of Athens, Alexandra General Hospital, Greece.
authors.forename: Dimitrios
authors.initials: D
authors.lastname: Papoutsis
authors.forename: George
authors.initials: G
authors.lastname: Daskalakis
authors.forename: Angeliki
authors.initials: A
authors.lastname: Antonakou
authors.forename: Alexandros
authors.initials: A
authors.lastname: Rodolakis
authors.forename: Spiridon
authors.initials: S
authors.lastname: Mesogitis
authors.forename: Aris
authors.initials: A
authors.lastname: Antsaklis
mesh_terms: D000328:Adult; D002584:Cervix Uteri / Q000033:anatomy & histology* / Q000000981:diagnostic imaging*; D003198:Computer Simulation; D005260:Female; D006801:Humans; D021621:Imaging, Three-Dimensional; D015588:Observer Variation; D009929:Organ Size; D014463:Ultrasonography