Stature estimation by semi-automatic measurements of 3D CT images of the femur.

Stature estimation is one of the most basic and important methods of personal identification. The long bones of the limbs provide the most accurate stature estimation, with the femur being one of the most useful. In all the previously reported methods of stature estimation using computed tomography (CT) images of the femur, laborious manual measurement was necessary. A semi-automatic bone measuring method can simplify this process, so we firstly reported a stature estimation process using semi-automatic bone measurement software equipped with artificial intelligence. Multiple measurements of femurs of adult Japanese cadavers were performed using automatic three-dimensional reconstructed CT images of femurs. After manually setting four points on the femur, an automatic measurement was acquired. The relationships between stature and five femoral measurements, with acceptable intraobserver and interobserver errors, were analyzed with single regression analysis using the standard error of the estimate (SEE) and the coefficient of determination (R2). The maximum length of the femur (MLF) provided the lowest SEE and the highest R2; the SEE and R2 in all cadavers, males and females, respectively, were 3.913 cm (R2 = 0.842), 3.664 cm (R2 = 0.705), and 3.456 cm (R2 = 0.686) for MLF on the right femur, and 3.837 cm (R2 = 0.848), 3.667 cm (R2 = 0.705), and 3.384 cm (R2 = 0.699) for MLF on the left femur. These results were non-inferior to those of previous reports regarding stature estimation using the MLF. Stature estimation with this simple and time-saving method would be useful in forensic medical practice.

Semi-automatic software-based 3D-angular measurement for Weight-Bearing CT (WBCT) in the foot provides different angles than measurement by hand.

BACKGROUND: The purpose of this study was to compare semi-automatic software-based angular measurement (SAM) with previously validated measurement by hand (MBH) regarding angle values and time spent for the investigator for Weight-Bearing CT (WBCT). METHODS: In this retrospective comparative study, five-hundred bilateral WBCT scans (PedCAT, Curvebeam, Warrington, PA, USA) were included in the study. Five angles (1st - 2nd intermetatarsal angle (IM), talo-metatarsal 1-angle (TMT) dorsoplantar and lateral projection, hindfoot angle, calcaneal pitch angle) were measured with MBH and SAM (Bonelogic Ortho Foot and Ankle, Version 1.0.0-R, Disior Ltd, Helsinki, Finland) on the right/left foot/ankle. The angles and time spent of MBH and SAM were compared (t-test, homoscesdatic). RESULTS: The angles differed between MBH and SAM (mean values MBH/SAM; IM, 9.1/13.0; TMT dorsoplantar, -3.4/8.2; TMT lateral. -6.4/-1.1; hindfoot angle, 4.6/21.6; calcaneal pitch angle, 20.5/20.1; each p < 0.001 except the calcaneal pitch angle, p = 0.35). The time spent for MBH / SAM was 44.5 ± 12 s / 12 ± 0 s on average per angle (p < 0.001). CONCLUSIONS: SAM provided different angles as MBH (except calcaneal pitch angle) and can currently not be considered as validated angle measurement method (except calcaneal pitch angle). The investigator time spent is 73% lower for SAM (12 s per angle) than for MBH (44.5 s per angle). SAM might be an important step forward for 3D-angle measurement of WBCT when valid angles are provided.

Impact of slice thickness on semi-automated measurements for volume and whole-tumor attenuation of colorectal hepatic metastases in multislice computed tomography.

BACKGROUND: Volumetric and whole-tumor attenuation assessment of tumor are of value in assessment of treatment. PURPOSE: To assess the impact of slice thickness on semi-automatic analyses (volume, whole-tumor attenuation) for small colorectal hepatic metastases. MATERIAL AND METHODS: Computed tomography (CT) data of patients with colorectal hepatic metastases at 1.5-, 3-, and 5-mm slice thickness were semi-automatically evaluated for volume and whole-tumor attenuation by two radiologists independently. Statistical analysis included paired samples t-test and concordance correlation coefficient (CCC) analysis according to the longest axial tumor diameter (10-20 mm, 20-30 mm, 30-40 mm). RESULTS: A total of 62 patients (32 men and 30 women) with 62 target tumors were included. The mean volume was significantly higher at 3- and 5-mm slice thicknesses in comparison with the reference (1.5 mm) for the target tumors between 10 mm and 20 mm (P = 0.0295, CCC = 0.9394 for 3 mm; P = 0.0029, CCC = 0.5129 for 5 mm, respectively) and at 5 mm slice thickness for the target tumors between 20 mm and 30 mm (P = 0.0071, CCC = 0.9102). For whole-tumor attenuation measurements, the significant difference was only seen at 5-mm slice thicknesses in comparison with the reference (1.5 mm) for the target tumors between 10 and 20 mm (P = 0.0015, CCC = 0.9389). CONCLUSION: Slice thickness of 1.5 mm might be suggested for semi-automated volumetric measurements, and slice thickness of no more than 3 mm for whole-tumor CT attenuation in hepatic metastasis between 10 mm and 20 mm.

Study on the practicality of the semi‐automatic measurement for the urogenital hiatus / 中华超声影像学杂志

Objective To determine the consistency of urogenital hiatus ( U H ) data between the semi‐automatic measurement and manual measurement using transperineal pelvic floor ultrasonography . Methods Total of 286 three‐dimensional images of minimal U H dimension were obtained . And they were divided into study group ( 100 images) and test group ( 186 images) randomly . T hree experts traced and created the w hole profile of the U H of those images in the study group by M AT LAB . T hen the semi‐automatic software was obtained through machine learning algorithms . In the test group , 6 parameters of U H ( including anterioposterior diameter , transverse diameter ,circumference , area ,left and right levator urethral gap distance) were measured by two experts ( D 1 and D2 ) both manually and semi‐automatically . T he time experts spent on measuring was also recorded and compared . Results T he time used for semi‐automatic measurement was significantly shorter than that for manual measurement [ ( 7 .49 ± 1 .51 ) s vs ( 42 .42 ± 11 .08) s ,( 7 .52 ± 1 .37) s vs ( 43 .45 ± 9 .09) s for D1 and D2 , t ＝ －12 .09 ,－13 .64 ,all P＝0 .00] . T he Pearson correlation coefficients between semi‐automatic and manual measurements of 6 parameters were 0 .857 －0 .985 ( P ＜ 0 .01) ,0 .853 －0 .979 ( P ＜ 0 .01 ) in D1 and D2 ,respectively . T he interclass correlation coefficients ( ICC) of six parameters were ranged from 0 .846 －0 .985 for D1 and 0 .843～0 .979 for D2 ( all P ＜ 0 .01 ) . T he Bland Altman plot also showed good agreement between two methods . Conclusions Intellectual recognition and semi‐automatic measurement has simplified the process for U H measurement ,and it is proved to be a reliable and timesaving method that is practical for clinical use .