Establishing Protocol-based Dose Metrics for Common Abdomen and Pelvis Computed Tomography Protocols

BACKGROUND AND AIM: The majority of the existing diagnostic reference levels (DRLs) that have been established for computed tomography (CT) are based on various anatomical locations, such as the head, chest, abdomen, etc. However, DRLs are initiated to improve radiation protection by conducting a comparison of similar examinations with similar objectives. The aim of this study was to explore the feasibility of establishing dose baselines based on common CT protocols for patients who underwent enhanced CT abdomen and pelvis exams. METHODS: Dose length product total (tDLPs), volumetric CT dose index (CTDIvol), size-specific dose estimate (SSDE), effective dose (E), and scan acquisition parameters for a total of 216 adult patients, who underwent an enhanced CT abdomen and pelvis exams over a one-year period, were obtained and retrospectively analyzed. Spearman coefficient and one-way ANOVA tests were used to check significant differences between dose metrics and the different CT protocols. RESULTS: The data exhibited 9 different CT protocols to acquire an enhanced CT abdomen and pelvis exam at our institute. Out of these, 4 were found more common, i.e., CT protocols were acquired for a minimum of 10 cases. Triphasic liver demonstrated the highest mean and median tDLPs across all 4 CT protocols. Triphasic liver protocol registered the highest E followed by gastric sleeve protocol with a mean of 28.7 and 24.7 mSv, respectively. Significant differences (p < 0.0001) were found between the tDLPs of anatomical location and the CT protocol. CONCLUSION: Evidently, wide variability exists across CT dose indices and patient dose metrics relying on anatomical-based dose baseline, i.e., DRLs. Patient dose optimizations require establishing dose baselines based on CT protocols rather than the anatomical location.

Endoscopic Diagnosis of Extra-Luminal Cancers.

The last 2 decades have seen an emergence of endoscopic technologies and techniques allowing for minimally invasive modalities for assessing and sampling lesions outside of the gastrointestinal lumen, including the chest, abdomen, and pelvis. Incorporating these new endoscopic approaches has revolutionized the diagnosis and staging of extra-luminal malignancies and has enabled more accessible and safer tissue acquisition.

Pitfalls in Prostate MR Imaging Interpretation.

Multiparametric MR imaging of the prostate is an essential diagnostic study in the evaluation of prostate cancer. Several entities including normal anatomic structures, benign lesions, and posttreatment changes can mimic prostate cancer. An in depth understanding of the pitfalls is important for accurate interpretation of prostate MR imaging.

The anatomical variability of obturator vessels: Systematic review of literature.

OBJECTIVE: To systematically assess available information about all variations of obturator vessels and to present the most surgically relevant types, their prevalence and calibre in order to provide a comprehensive overview for both anatomists and clinicians. MATERIALS AND METHODS: A total of 2689 studies were found via searching the online databases. After applying exclusion criteria 44 studies were assessed. The cadaveric studies, CT angiographies, and clinical studies were included. Number of hemipelves, prevalence of each variation and calibre of identified vessels were studied. Each variation was classified as aberrant obturator artery/vein, aberrant accessory obturator artery/vein or anastomosis. RESULTS: In included studies the average incidence of the variant obturator artery was 26% with the aberrant obturator artery being the most frequent type (with the mean calibre 2.10 mm, SD = 0.35 mm), while the overall incidence of the variant obturator vein was 55%. Presented venous structures had the mean calibre of 2.98 mm (SD = 0.56 mm). CONCLUSIONS: According to reviewed studies, variant obturator vessels are present in a great number of patients. Due to their possible calibre larger than 3 mm they represent a structure of high clinical importance. It is important to unify the terminology and to stress out the significance to all clinicians.

A systematic review of the physiological and biomechanical differences between males and females in response to load carriage during walking activities.

The purpose of this review was to systematically assess literature on differences between males and females in the physiological and biomechanical responses to load carriage during walking. PubMed, CINAHL, Scopus, Web of Science and the Cochrane library were searched. A total of 4637 records were identified and screened. Thirty-three papers were included in the review. Participant characteristics, load carriage conditions, study protocol, outcome measures and main findings were extracted and qualitatively synthesised. Absolute oxygen uptake and minute ventilation were consistently greater in males but there were limited sex-specific differences when these were expressed relative to physical characteristics. There is limited evidence of sex-specific differences in spatio-temporal variables, ground reaction forces (normalised to body mass) or sagittal plane joint angles with load. However, differences have been found in hip and pelvic motions in the frontal and horizontal planes, which might partly explain an economical advantage for females proposed by some authors.

Managing Inflammatory Myofibroblastic Tumor of the Uterus: A Case Report and Comprehensive Review of Pathological and Therapeutic Approaches.

BACKGROUND Inflammatory myofibroblastic tumor (IMT) is a rare disease, and uterine IMT is even rarer. IMT is hard to distinguish from endometrial polyp and submucous myoma. The treatment of IMT is still controversial. Here, we report a case of uterine IMT, discussing both pathological and therapeutic aspects. CASE REPORT A 32-year-old woman was admitted to our hospital for a uterine mass, hypermenorrhea, and anemia. She had been suffering from these symptoms for almost a year. Pelvic ultrasound and MRI revealed a mass about 7 cm in diameter at the bottom of the uterus. Serum tumor markers were negative. She was diagnosed with submucous fibroids of the uterus. Then she underwent hysteroscopic mass resection. Histopathological and immunohistochemistry stain analysis revealed IMT of the uterus. Due to the malignant potential of IMT, she was advised to undergo a total hysterectomy, but she refused because she wanted to retain the uterus and fertility. A watch-and-wait strategy without any therapy was chosen, and the patient is currently disease-free after 18-month follow-up. CONCLUSIONS IMT is a disease with malignant potential and may recur at a late stage; hence, a correct diagnosis is essential for patients with IMT. Surgery is the preferred treatment for IMT. For early-stage, young women who want to preserve fertility, conservative surgery is acceptable, but close follow-up is required to avoid recurrence and metastasis. If a patient cannot undergo surgery or the disease has metastasized extensively, targeted therapy for ALK gene, immunotherapy, and other methods can be considered.

Quantifying anterior pelvic roll during total hip arthroplasty in the lateral decubitus position.

BACKGROUND: Unintended pelvic positional change is an acknowledged intra-operative problem for hip arthroplasty, seen commonly with procedures performed in the lateral position. If unrecognised, such changes can dramatically alter final acetabular component anteversion potentially resulting in suboptimal construct performance. It has previously been suggested that pelvic roll of just 13° may be enough to place an otherwise perfectly orientated cup outside of conventional ± 10° safe zones. Using the real-time tracking capacity of a commercially available optical navigation system, we aimed to accurately quantify pelvic roll occurring during total hip arthroplasties (THAs) performed in the decubitus position. METHODS: Prospectively collected data for 107 consecutive, unilateral, THAs were interrogated to determine the magnitude of pelvic movement around a central longitudinal axis (i.e. AP roll). Correlation statistics with patient age and body mass index (BMI) were also calculated. RESULTS: A mean pelvic roll of 9.5° was observed, being anterior in 96% of cases. Of these, 18.3% of hips had a magnitude of roll greater than 13°. There were no statistically significant independent correlations observed between age (p = 0.87) or BMI (p = 0.59) and mean roll. CONCLUSIONS: Errors in achieving acetabular target version may result in numerous post-operative concerns including instability/dislocation, bearing wear, squeaking, range-of-movement limitation and increased revision rate. In a general cohort, our findings suggest a mean anterior pelvic roll during THA of nearly 10°. Without purposeful correction, this may cause substantial deviation from intended target positions. Future work is indicated to map changing pelvic roll during THA which is likely to follow a nonlinear trajectory. Level of evidence: IV. .

Challenges of circulatory unstable pelvic fracture in Greenland.

Management of circulatory unstable pelvic fracture in Greenland - from a remote village to Level 1 Trauma center. This case report depicts the transportation of an unstable patient in a rural area, where transportation of the critically ill patient is inherently difficult due to infrastructure. The case report brings knowledge to the reader of logistic conditions in Greenland, which differ greatly from those in Denmark. Furthermore, it highlights the importance of knowledge of damage control surgery and of great intercollegiate cooperation.

Pelvis-Sacrum-Lumbar Spine Injury Characteristics From Underbody Blast Loading.

INTRODUCTION: Combat-related injuries from improvised explosive devices occur commonly to the lower extremity and spine. As the underbody blast impact loading traverses from the seat to pelvis to spine, energy transfer occurs through deformations of the combined pelvis-sacrum-lumbar spine complex, and the time factor plays a role in injury to any of these components. Previous studies have largely ignored the role of the time variable in injuries, injury mechanisms, and warfighter tolerance. The objective of this study is to relate the time or temporal factor using a multi-component, pelvis-sacrum-lumbar spinal column complex model. MATERIALS AND METHODS: Intact pelvis-sacrum-spine specimens from pre-screened unembalmed human cadavers were prepared by fixing at the superior end of the lumbar spine, pelvis and abdominal contents were simulated, and a weight was added to the cranial end of the fixation to account for torso effective mass. Prepared specimens were placed on the platform of a custom vertical accelerator device and aligned in a seated soldier posture. An accelerometer was attached to the seat platen of the device to record the time duration to peak velocity. Radiographs and computed tomography images were used to document and associate injuries with time duration. RESULTS: The mean age, stature, weight, body mass index, and bone density of 12 male specimens were as follows: 65 ± 11 years, 1.8 ± 0.01 m, 83 ± 13 kg, 27 ± 5.0 kg/m2, and 114 ± 21 mg/cc. They were equally divided into short, medium, and long time durations: 4.8 ± 0.5, 16.3 ± 7.3, and 34.5 ± 7.5 ms. Most severe injuries associated with the short time duration were to pelvis, although they were to spine for the long time duration. CONCLUSIONS: With adequate time for the underbody blast loading to traverse the pelvis-sacrum-spine complex, distal structures are spared while proximal/spine structures sustain severe/unstable injuries. The time factor may have implications in seat and/or seat structure design in future military vehicles to advance warfighter safety.

Impact forces in backward falls: Subject-specific video-based rigid body simulation of backward falls.

A critical missing component in the study of real-world falls is the ability to accurately determine impact forces resulting from the fall. Subject-specific rigid body dynamic (RBD) models calibrated to video captured falls can quantify impact forces and provide additional insights into injury risk factors. RBD models were developed based on five backward falls captured on surveillance video in long-term care facilities in British Columbia, Canada. Model joint stiffness and initial velocities were calibrated to match the kinematics of the fall and contact forces were calculated. The effect of joint stiffnesses (neck, lumbar spine, hip, and knee joint) on head contact forces were determined by modifying the calibrated stiffness values ±25%. Fall duration, fall trajectories, and maximum velocities showed a close match between fall events and simulations. The maximum value of pelvic velocity difference between Kinovea (an open-source software 2D digitization software) and Madymo multibody modeling was found to be 6% ± 21.58%. Our results demonstrate that neck and hip stiffness values have a non-significant yet large effect on head contact force (t(3) = 1, p = 0.387 and t(3) = 2, p = 0.138), while lower effects were observed for knee stiffness, and the effect of lumbar spine stiffness was negligible. The subject-specific fall simulations constructed from real world video captured falls allow for direct quantification of force outcomes of falls and may have applications in improving the assessment of fall-induced injury risks and injury prevention methods.

Three-dimensional printing versus traditional surgery for inveterate pelvic and acetabular fractures: A retrospective study of 37 patients.

Treatment of deformed pelvic and acetabular fractures is a considerable challenge for orthopedic surgeons. The aim of this study was to assess the availability of a three-dimensional (3D) printing model used in patients with inveterate pelvic and acetabular fractures by comparing 3D printing technology with conventional surgery. We conducted a retrospective review of patients with inveterate pelvic and acetabular fractures treated in our department between January 2008 and June 2020. The patients were divided into 2 groups according to their willingness. Perioperative data and clinical outcomes were compared to evaluate clinical efficacy. The t-test, Fisher exact test, and multivariable logistic regression analysis were conducted. A P value of .05 or less was considered to be statistically significant (two-tailed). Thirty-seven patients were enrolled in our study. Seventeen patients were divided into the case group treated by 3D printing model-assisted preoperative planning, and 20 patients were divided into the control group treated by conventional surgery. Patients treated with the 3D printing model had significantly shorter operation times, less blood loss, and shorter fluoroscopy times. Patients in the case group also showed better pain relief according to visual analog scale scores. However, the elevations in pelvis and hip joint functional outcomes were similar between the 2 groups, and no significant difference was shown in the radiological result. The usage of 3D printing techniques in patients with inveterate pelvic and acetabular fractures is of great importance in preoperative preparation and optimization of surgery but cannot improve postoperative function compared with conventional treatment.

Bi-parametric prostate MRI with a recall system for contrast enhanced imaging: Improving accessibility while maintaining quality.

PURPOSE: To review the efficacy of a recall system for bi-parametric non-contrast prostate MRI (bp-MRI). METHODS: A bi-parametric protocol was instituted in July 2020 for all patients who had a prostate MRI requested, excluding those after treatment of prostate cancer, patients with hip prosthesis or pacemaker, and those who lived out-of-town. The protocol consisted of tri-planar T2-weighted and diffusion weighted images (DWI) (b = 50, 800 s/mm2 for ADC map; b = 1,500 s/mm2 acquired separately) in accordance with the Prostate Imaging Reporting & Data system (PI-RADS) v2.1 guidelines. After interpretation of bp-MRI exams, patients with equivocal (PI-RADS 3) lesions in peripheral zone (PZ) or any technical limitations were recalled for contrast administration. RESULTS: Out of 909 bp-MRI scans performed from July 2020 to April 2021, only 52 (5.7 %) were recalled, of which 46 (88.5 %) attended. Amongst these, 41/52 (78.8 %) were recalled for PZ PI-RADS 3 lesions, while the rest of 11 (21.2 %) cases were recalled for technical reasons. Mean time to subsequent recall scan was 11.6 days. On assessment of post-contrast imaging, 29/46 (63 %) cases were upgraded to PI-RADS 4 while 17/46 (37 %) remained PI-RADS 3. This system avoided contrast-agent use in 857 patients, with contrast cost savings of €64,620 (US$68,560) and 214 hours 15 minutes of scanner time was saved. This allowed 255 additional bp-MRI scans to be performed, reducing the waitlist from 1 year to 2-3 weeks. CONCLUSION: A bi-parametric prostate MRI protocol with a robust recall system for contrast administration not only saved time eliminating the marked backlog but was also more cost efficient without compromising the quality of patient care.

[Feasibility analysis and nail planning ofS2 iliac crest screw placement in children].

OBJECTIVE: To evaluate the feasibility of S2 alar iliac screw insertion in Chinese children using computerized three-dimension reconstruction and simulated screw placement technique, and to optimize the measurement of screw parameters. METHODS: A total of 83 pelvic CT data of children who underwent pelvic CT scan December 2018 to December 2020 were retrospectively analyzed, excluding fractures, deformities, and tumors. There were 44 boys and 39 girls, with an average age of (10.66±3.52) years, and were divided into 4 groups based on age (group A:5 to 7 years old;group B:8 to 10 years old;group C:11-13 years old;group D:14 to 16 years old). The original CT data obtained were imported into Mimics software, and the bony structure of the pelvis was reconstructed, and the maximum and minimum cranial angles of the screws were simulated in the three-dimensional view with the placement of 6.5 mm diameter S2 alar iliac screws. Subsequently, the coronal angle, sagittal angle, transverse angle, total length of the screw, length of the screw in the sacrum, width of the iliac, and distance of the entry point from the skin were measured in 3-Matic software at the maximum and minimum head tilt angles, respectively. The differences among the screw parameters of S2 alar iliac screws in children of different ages and the differences between gender and side were compared and analyzed. RESULTS: In all 83 children, 6.5 mm diameter S2 iliac screws could be placed. There was no significant difference between the side of each screw placement parameter. The 5 to 7 years old children had a significantly smaller screw coronal angle than other age groups, but in the screw sagittal angle, the difference was more mixed. The 5 to 7 years old children could obtain a larger angle at the maximum head tilt angle of the screw, but at the minimum cranial angle, the larger angle was obtained in the age group of 11 to 13 years old. There were no significant differences among the age groups. The coronal angle and sagittal angle under maximum cephalic angle and minimum cranial angle of 5 to 7 years old male were (40.91±2.91)° and (51.85±3.75)° respectively, which were significantly greater than in female. The coronal angle under minimum cranial angle was significantly greater in girls aged 8-10 years old than in boys. For the remaining screw placement angle parameters, there were no significant differences between gender. The differences in the minimum iliac width, the screw length, and the length of the sacral screws showed an increasing trend with age in all age groups. The distance from the screw entry point to the skin in boys were significantly smaller than that of girls. The minimum width of the iliac in boys at 14 to 16 years of age were significantly wider than that in girls at the same stage. In contrast, in girls aged 5 to 7 years and 11 to 13 years, the screw length was significantly longer than that of boys at the same stage. CONCLUSION: The pelvis of children aged 5 to 16 years can safely accommodate the placement of 6.5 mm diameter S2 alar iliac screws, but the bony structures of the pelvis are developing and growing in children, precise assessment is needed to plan a reasonable screw trajectory and select the appropriate screw length.

Stress-shielding resistant design of custom pelvic prostheses using lattice-based topology optimization.

Endoprosthetic reconstruction of the pelvic bone using 3D-printed, custom-made implants has delivered early load-bearing ability and good functional outcomes in the short term to individuals with pelvic sarcoma. However, excessive stress-shielding and subsequent resorption of peri­prosthetic bone can imperil the long-term stability of such implants. To evaluate the stress-shielding performance of pelvic prostheses, we developed a sequential modeling scheme using subject-specific finite element models of the pelvic bone-implant complex and personalized neuromusculoskeletal models for pre- and post-surgery walking. A new topology optimization approach is introduced for the stress-shielding resistant (SSR) design of custom pelvic prostheses, which uses 3D-printable porous lattice structures. The SSR optimization was applied to a typical pelvic prosthesis to reconstruct a type II+III bone resection. The stress-shielding performance of the optimized implant based on the SSR approach was compared against the conventional optimization. The volume of the peri­prosthetic bone predicted to undergo resorption post-surgery decreased from 44 to 18%. This improvement in stress-shielding resistance was achieved without compromising the structural integrity of the prosthesis. The SSR design approach has the potential to improve the long-term stability of custom-made pelvic prostheses.

Tumour, narrow pelvis and surgery specific factors for total mesorectal excision quality and morbidity following rectal cancer resection.

BACKGROUND: Pelvic anatomy is critical in challenging rectal resections. This study investigated how pelvic anatomy relates to total mesorectal excision (TME) quality, anastomotic leakage rate, and long-term oncological outcomes. METHODS: Patients undergoing elective rectal cancer resection from 2008 to 2017 in an Austrian institution were retrospectively reviewed regardless of the surgical approach. CT scans were analysed for pelvic measurements and volumes. The primary outcomes of interest were the correlation between pelvic dimensions and the TME quality and anastomotic leakage. Subanalysis was done by surgical approach (open, laparoscopic, transanal TME). Secondary outcomes were overall and disease-free survivals. RESULTS: Among 154 eligible patients, 112 were included. The angle between pubic symphysis and promontory significantly correlated with worse TME grades (TME grade 1: mean(s.d.) 102.7(5.7)°; TME grade 2: 92.0(4.4)°; TME grade 3: 91.4(3.6)°; P < 0.001). A significantly lower distance between tumour and circumferential resection margin (CRM) was observed in grade 3 resections, whereas no difference appeared in grade 1 and grade 2 resection (TME grade 1: mean(s.d.) 11.92(9.4) mm; TME grade 2: 10.8(8.1) mm; TME grade 3: 3.1(4.1) mm; P = 0.003). The anastomotic leakage rate was significantly higher in case of a lower CRM (patients with anastomotic leakage: mean(s.d.) 6.8(5.8) mm versus others: 12.6(9.8) mm, P = 0.027), but not associated with pelvimetry measurements. The transanal TME (TaTME) subgroup displayed a wider angle between the pubic symphysis and promontory, younger age and improved TME quality compared to others (respectively, mean TME grades in TaTME versus open versus laparoscopic: 1.0 ± 0.0, 1.5 ± 0.7 and 1.3 ± 0.5, P = 0.013). Finally, oncological survival was not impacted by pelvic measurements or worse TME quality. CONCLUSION: The angle between the pubic symphysis and promontory and the distance between tumour and CRM were associated with worse TME grades. The anastomotic leakage was associated with a lower CRM but not with pelvimetric measures.

Weakly supervised segmentation of uterus by scribble labeling on endometrial cancer MR images.

Uterine segmentation of endometrial cancer MR images can be a valuable diagnostic tool for gynecologists. However, uterine segmentation based on deep learning relies on artificial pixel-level annotation, which is time-consuming, laborious and subjective. To reduce the dependence on pixel-level annotation, a method of weakly supervised uterine segmentation on endometrial cancer MRI slices is proposed, which only requires scribble label and is enhanced by pseudo-label technology, exponential geodesic distance loss and input disturbance strategy. Specifically, the limitations caused by the shortage of supervision are addressed by dynamically mixing the two outputs of the dual branch network to generate pseudo-labels, expanding supervision information and promoting mutual supervision training. On the other hand, considering the large difference of grayscale intensity between the uterus and surrounding tissues, the exponential geodesic distance loss is introduced to enhance the ability of the network to capture the edge of the uterus. Input disturbance strategies are incorporated to adapt to the flexible and variable characteristics of the uterus and further improve the segmentation performance of the network. The proposed method is evaluated on MRI images from 135 cases of endometrial cancer. Compared with other four weakly supervised segmentation methods, the performance of the proposed method is the best, whose mean DI, HD95, Recall, Precision, ADP are 92.8%, 11.632, 92.7%, 93.6%, 6.5% and increasing by 2.1%, 9.144, 0.6%, 2.4%, 2.9% respectively. The experimental results demonstrate that the proposed method is more effective than other weakly supervised methods and achieves similar performance as those fully supervised.

Trunk resistance to mechanical perturbations, associations with low back pain, pain-related cognitions and movement precision.

BACKGROUND: Pain-related cognitions are associated with motor control changes in people with chronic low-back pain (CLBP). The mechanism underlying this association is unclear. We propose that perceived threat increases muscle-spindle-reflex-gains, which reduces the effect of mechanical perturbations, and simultaneously decreases movement precision. AIM: To evaluate effects of CLBP and pain-related cognitions on the impact of mechanical perturbations on trunk movement, and associations between these perturbation effects and movement precision. METHODS: 30 participants with CLBP and 30 healthy controls, performed two consecutive trials of a seated repetitive reaching task. During both trials participants were warned for mechanical perturbations, which were only administered during the second trial. The perturbation effect was characterized by the deviation of the trajectory of the T8 vertebra relative to the sacrum. Trunk movement precision was expressed as tracking error during a trunk movement target tracking task. We assessed pain-related cognitions with the task-specific 'Expected Back Strain'-scale (EBS). We used a two-way-Anova to assess the effect of Group (CLBP vs back-healthy) and dichotomized EBS (higher vs lower) on the perturbation effect, and a Pearson's correlation to assess associations between perturbation effects and movement precision. FINDINGS: Higher EBS was associated with smaller perturbation effects (p ≤ 0.011). A negative correlation was found between the perturbation effect and the tracking error, in the higher EBS-group (r = -0.5, p = 0.013). INTERPRETATION: These results demonstrate that pain-related cognitions influence trunk movement control and support the idea that more negative pain-related cognitions lead to an increased resistance against perturbations, at the expense of movement precision.

Predictive estimation of ovine hip joint centers: A regression approach.

Estimation of the hip joint center in ovine biomechanical analysis is often overlooked or estimated using a marker on the greater trochanter which can result in large errors that propagate through subsequent analyses. The purpose of this study was to develop a novel method of estimating the hip joint centers in sheep to facilitate more accurate analysis of ovine biomechanics. CT scans from 16 sheep of varying ages, weight, sex, and phenotypes were acquired and the data was used to calculate the known hip joint center by sphere fitting the femoral head. Anatomical measurements and additional subject information were used to create a variety of regression models to estimate the hip joint centers in absence of CT data. The best regression equation created utilized markers placed on the tuber coxae and tuber ischii of the pelvis and resulted in a mean 3D Euclidean distance error of 6.43 ± 2.22 mm (mean ± standard deviation) between the known and estimated hip joint center. The regression models produced allow for more detailed, accurate and robust analysis of sheep biomechanics.

Evaluation of the effect of pelvis type in percutaneous acetabular column fixation: a computed tomography study.

This study aimed to evaluate the effect of pelvis type in percutaneous acetabular column fixation. What is the effect of pelvis type in percutaneous acetabular colon fixation? The available pelvic computed tomography (CT) scans which were obtained in the diagnostic imaging center with a 1 mm slice width were evaluated. The pelvic type was classified with the help of MPR (Multiplanar Reformat) and 3D (Three Dimensional) imaging modes. All evaluated bony pelvic structures were anatomically intact. 40 types of android, gynecoid, anthropoid, and platypelloid pelvis were determined. CT sections were created in MPR imaging mode. Anterior obturator oblique (AOO) and inlet images were created for anterior column evaluation, while iliac oblique (IO) and outlet images were created for posterior column evaluation. The possibility of obtaining a linear corridor for acetabular columns was investigated by measuring corridor width and lengthon images of pelvic CTs. A linear corridor could not be obtained between the pubic tubercle and the supraacetabular region of 12 (30%) CTs in the anterior column of gynecoid pelvis group. The diameter of the anterior column corridor was below 5.5 mm in 10 (25%) of Gynecoid pelvis group, 5 (12.5%) of Anthropoid pelvis group, and 10 of Platypelloid pelvis group, , and all those scans belonged to the female gender. There was a statistically significant difference between pelvis types in terms of anterior and posterior column diameters (p <0.001). While the android pelvis type had the highest diameter and corridor length in both anterior column and posterior column measurements, the gynecoid pelvic type had the lowest diameter and corridor length. In the evaluations made according to gender, both anterior and posterior column diameters were larger and longer in males than in females (p <0.001). Pelvis type is an important factor which can affect anterior and posterior column diameter and length of acetabulum. Pelvic typing before acetabular surgery can help the surgeon determining the most appropriate patient position, surgical approach, and implant selection. Level of Evidence: Level 2.