Revista nº 814

3D morphometric analysis of the cadaveric colon | Trebollé JF, et al. 262 Actual Med. 2021; 106(814): 260- 270 control performed in supine decubitus without pneumoperitoneum. The remaining series were performed with 15 mm Hg of pneumoperitoneum. Series 02 (PNEUMOPERITONEUM) was performed in supine position. Series 03 (RIGHT SIDE) was performed with 15º right lateral decubitus positioning. Series 04 (LEFT SIDE) was performed with 15º left lateral decubitus positioning. In the following series, a 15º Trendelenburg tilt was applied. Series 05 (TRENDELENBURG) was performed with a 15º Trendelenburg tilt. Series 06 (TRENDELENBURG AND RIGHT SIDE) included both Trendelenburg tilt and 15º right lateral decubitus positioning. Series 07 (TRENDELENBURG AND LATERAL LEFT) included Trendelenburg tilt and 15º left lateral decubitus positioning. In the last three series, manipulation of the colon was introduced by elevating the greater omentum and exposing the transverse colon. Series 08 (OMENTUM) only included the elevation of the greater omentum with 15º Trendelenburg tilt. Series 09 (OMENTUM AND RIGHT SIDE) added 15º right lateral decubitus positioning. Series 10 (OMENTUM AND LEFT SIDE) added 15º left lateral decubitus positioning. The same order of manipulation was always followed for all three cadavers. Obtaining and processing CT images Following the described protocol, DICOM images were obtained using 3-mm CT scan sections. These images were processed with OsiriX software. The colon surface was manually individualized in all sections, and its image density was modified to obtain three-dimensional reconstructions. Chromatic changes in the three-dimensional images were made using Adobe Photoshop Elements 11. After bringing the three-dimensional images to the frontal plane, the reference points were marked for the proposed measures. These points were the anterior superior iliac spines (SPINE); the midpoint of the pubic symphysis (PUBIS); the root of the superior mesenteric artery (SMA); the root of the inferior mesenteric artery (IMA); the highest point of the colon in the right hemiabdomen, in the transition zone between the ascending colon and the transverse colon (HF); and the highest point of the colon in the left hemiabdomen, in the transition zone between the transverse colon and the descending colon (SA). Morphometric study The cadavers were always studied in the frontal position. These measurements were performed using the computer program ImageJ and were calculated in pixels, which were later transformed to centimeters, and in sexagesimal degrees. The reference measurement was the SPINE-SPINE distance. To minimize the possible degree of distortion that could result from modifying the cadavers’ position relative to supine decubitus, this measure was used to apply a correction factor in each series. Thus, the differences observed in this measure after the cadavers were successively repositioned were less than 2‰. A correlation analysis was performed to assess the dependence of some variables on others. A total of 390 measurements were performed (Figure 1). Series 01 of the three cadavers was used as a reference and 159 measurements were modified more than 5% compared to this baseline. To systematize these results, we divided them into four sections depending on the angle and its components (Figure 2). The PUBIS-SMA distance increased in all series in cadaver 1; in cadaver 2, it increased in series 02; in cadaver 3, it was not modified. The PUBIS-IMA distance increased in the last four series in cadaver 1 and decreased in series 04; in cadaver 2 it increased in all cases; in cadaver 3, it was not modified. The SMA- IMA distance increased in cadaver 1 in all series except for series 07; in cadaver 2, it decreased in all series except series 02, in which it did not change; in cadaver 3, it increased in all series except series 04, in which it did not change. The correlation test showed very high values between PUBIS-SMA and PUBIS-IMA (r = 0.94) and between PUBIS-IMA and SMA-IMA, although the correlation was negative (r = -0.86). The correlation between PUBIS-SMA and SMA-IMA was high and negative (r = -0.64) (Table 1). The HF-SMA-SA angle increased in all series in cadaver 1; in cadaver 2, it increased in series 02 and 04 and decreased in series 07, 08, 09 and 10; in cadaver 3, it only changes in series 09, in which it increased. The SMA-HF distance in cadaver 1 increased in series 02, 03, 05, 06, 07, 08 and 09 and decreased in series 04; in cadaver 2, it increased in series 04, 08 and 09; in cadaver 3, it increased in series 08 and 10 and decreased in series 09. The SMA-SA distance decreased in all series in cadaver 1; in cadaver 2, it decreased in series 02; in cadaver 3, it increased in series 03, 04, 08 and 10. The correlation test showed high values for the relationships among these variables (Table 2). The HF-IMA-SA angle was modified in five series in cadaver 1 in various direction and magnitudes; in cadaver 2, it increased in all series from 02 to 07 and decreased in series 08 and 09. In cadaver 3, it only changed in the last three series, in which it decreased. The IMA-HF distance decreased in series 04, 07, 09 and 10 in cadaver 1; in cadaver 2, it increased in series 02, 03, 04, 08, 09 and 10 and decreased in series 07. In cadaver 3, it changed in seven series, with different directions and magnitudes. The IMA-SA distance in cadaver 1 changed irregularly in four series; in cadaver RESULTS