3D Planning Research Articles

AUTOMATIC BUILDING EXTRACTION FROM UAV-BASED IMAGES AND DSMs USING DEEP LEARNING

Abstract. Accurate and automatic building footprint extraction from single UAV images has become essential in many photogrammetry and remote sensing applications such as 3D building modeling, smart city, monitoring, disaster management, and urban planning. In this paper, the capability of U-Net architecture with ResNet as the backbone of the network is investigated to extract the building footprints from UAV-based orthophotos and normalized Digital Surface Models (nDSMs) considering the complementary nature of RGB and height information. The data has been captured from five non-overlapping rural scenes of Yazd province, Iran. After pre-processing, the training and test datasets are prepared to evaluate the performance of U-Net using different hyperparameters and input channels such as RGB (only orthophotos) and RGBD (orthophotos and nDSMs). The experiments highlight the effectiveness of height information to detect and extract the building footprints with significant improvements in precision from 89% to 97% and in recall from 77% to 91%.

Cup Overhanging in Anatomic Socket Position or High Hip Center of Rotation in Total Hip Arthroplasty for Crowe III and IV Dysplasia: A CT-Based Simulation.

Cup overhanging in total hip arthroplasty is a predisposing factor to iliopsoas impingement. In dysplastic hips, cup implantation was simulated in an anatomic hip center of rotation (AHCR) and in high hip center (HHCR). We sought to assess: (1) the percentage of prominent cups; (2) quantify the cup protrusion at different sites on frontal, axial and sagittal views. In 40 Crowe III-IV hips, using a 3D CT-based planning software, cup planning in AHCR and HHCR (CR height ≥ 20 mm) was performed for every hip. Cup prominence was assessed on every plane. HHCR cups were less anteverted (p < 0.01), less medialized (p < 0.001) and less caudal (p = 0.01) than AHCR sockets. AHCR cups were more frequently prominent on at least one plane (92.5% vs. 77.5%), with minimal agreement between the two configurations (k = 0.31, p = 0.07). AHCR cups protruded more than HHCR sockets in the sagittal (p = 0.02) and axial planes (p < 0.001). Axially, at the center of the cup, prominence 6−11 mm occurred in nine (22.5%) AHCR and one (2.5%) HHCR socket. In conclusion, while a routine high hip center should not be recommended, cup placement at a center of rotation height < 20 mm is associated with higher rates and magnitudes of anterior cup protrusion in severe dysplasia.

Application of 3D Modeling and 3D Printing Methods in Preoperative Planning of Cranioplasty and Preoperative Personalized Training in Treatment Cranio-synostoses

On the example of a clinical case, we used software 3D modeling of the reconstruction of the shape of the skull of a child aged 2 years and 5 months with metopic craniosynostosis, as well as manual training using a craniotomy on an individual 3D model of the patient's skull before surgery. The use of a plastic 3D model of a particular patient made it possible to conduct a “trial, training operation” to work out the optimal osteotomy geometry. An intraoperative evaluation of the result obtained on a visual scanner was also carried out.Purpose of the study. Improving the result of surgical treatment of a child with metopic craniosynostosis using preoperative 3D planning and personalized simulation of a planned operation. For the purpose of preoperative planning we used an algorithm with the inclusion of 3D technologies: preoperative modeling on software, simulation of surgery on plastic models of the skull, surgical intervention along craniotomy lines, intraoperative visual scanning and assessment of the results of skull reconstruction.Conclusion. The preoperative 3D modeling of the skull formed a complete plan for individual reconstructive changes in the skull in our patient with metopic craniosynostosis over the age of two years, and allowed us to perform a “trial, training operation” on a plastic model to work out the optimal osteotomy geometry. This made it possible to provide the optimal technique for a real operation, speed up its implementation, reduce trauma and blood loss, the duration of anesthesia, and, in combination, improve the results of surgical treatment.

Innovative methods and developments in oral care. 3D planning in oral and maxillofacial surgery

With the use of cone beam computed tomography, intraoral scanning and 3D stereophotogrammetry, a virtual 3D head model of a patient can be reconstructed with image fusion. In this way, the malposition, deficiency and other anomalies at the level of bone, dentition and soft tissue can be quantified objectively. The desired position of the dentition, occlusion and soft tissue in the facial profile can be virtually drawn in and used as a guideline for treatment planning. Based on the principle of backward planning, it is possible to determine what repositioning of the jaw is required, where there is a need for bone augmentation and how many dental implants are necessary to obtain the desired treatment outcome. From this perspective, 3D treatment planning has become a treatment standard for the 4 clinical pillars supporting oral and maxillofacial surgery, specifically orthognathic surgery, implantology, craniofacial surgery and head & neck oncology. 3D planning has influenced today's workflow, planning of complex surgery and contributed to useful further innovations and efficient healthcare.

Application of 3D printed patient-specific instruments in the treatment of large tibial bone defects by the Ilizarov technique of distraction osteogenesis.

The Ilizarov technique of distraction osteogenesis is an effective treatment for tibia defect. However, repeated attempts to reduce due to the complexity of the bone defect during the operation will increase the operation time and iatrogenic injury, and excessive radiation exposure. Three-dimensional (3D)-printed patient-specific instrument (PSI) for preoperative 3D planning and intraoperative navigation have the advantages of accuracy and visualization. The purpose of this study is to investigate whether 3D-printed PSI is helpful to correct tibial bone defects accurately and effectively. From May 2019 to September 2022, 19 patients with tibial bone defects were treated, including 9 males and 10 females, aged 37 to 64 years. There were 4 cases in proximal tibia, 9 in midshaft tibia and 6 in distal tibia. All were treated with Ilizarov technique of distraction osteogenesis. 3D-printed PSI was used in 9 cases, while traditional surgery was used in 10 cases. All patients underwent computed tomography before surgery. Computer software was used to analyze the measurement results, design and print PSI. During the operation, PSI was used to assist in reduction of tibia. Operation times were recorded in all cases, the number of fluoroscopy during the operation, and the varus/valgus, anteversion/reversion angle after the operation were measured. All measurement data were expressed by means ± SD, and Student's t test was used to examine differences between groups. The chi square test or Fisher's precise test was used to compare the counting data of the two groups. All PSI matched well with the corresponding tibia bone defect, and were consistent with the preoperative plan and intraoperative operation. The affected limb had a good reduction effect. The operation time from the beginning of PSI installation to the completion of Ilizarov ring fixator installation was 31.33 ± 3.20 min, while that in the traditional operation group was 64.10 ± 6.14 min (p < 0.001). The times of fluoroscopy in the PSI group during operation was 10.11 ± 1.83, and that in the traditional operation group was 27.60 ± 5.82. The reduction effect of tibia in PSI group was better than that in traditional operation group, with the average angle of PSI group is 1.21 ± 0.24°, and that of traditional operation group is 2.36 ± 0.33° (p < 0.001). The PSI simplifies procedures, reduces the difficulty of the operation, improves the accuracy of the operation, and provides a good initial position when used in distraction osteogenesis to treat the tibial defects.

Impacted bone allograft personalised by a novel 3D printed customization kit produces high surgical accuracy in medial opening wedge high tibial osteotomy: a pilot study

PurposeContemporary medial opening wedge high tibial osteotomy (MOWHTO) still seems to struggle with inconsistent accuracy outcomes. Our objective was to assess surgical accuracy and short-term clinical outcomes when using 3D planning and a patient-specific instrumentation (PSI) kit to prepare customized bone allografts.MethodsThirty subjects (age 48y ± 13) were included in a double-center prospective case series. A low-dose CT-scan was performed to generate 3D bone models, a MOWHTO was simulated, and PSI was designed and 3D printed based on the complementary negative of the planned osteotomy gap. Clinical outcome was assessed at two, four, 12 weeks and one year using NRS, KOOS, UCLA activity score, EQ-5D and anchor questions. A linear-mixed model approach was implemented for data analysis.ResultsPreoperative 3D values were 175.0° ± 2.2 mechanical tibiofemoral angle (mTFA), 85.0° ± 3.0 medial proximal tibial angle (MPTA), and 94.1° ± 3.4 medial posterior tibial slope (MPTS). Target planning ranged from slight varus to the lateral tibial spine (slight valgus). Postoperative 3D analysis showed an accuracy of 1.1° ± 0.7 ΔMPTA (p = 0.04) and 1.2° ± 1.2 ΔMPTS (p = 0.11). NRS decreased from baseline 6.1 ± 1.9 to 2.7 ± 1.9 at four weeks (p < 0.001) and 1.7 ± 1.9 at one year (p < 0.001). KOOS increased from 31.4 ± 17.6 to 50.6 ± 20.6 at 12 weeks (p < 0.001) and to 71.8 ± 15.6 at one year (p < 0.001).ConclusionThe study suggests that 3D printed instrumentation to personalize structural bone allograft is a viable alternative method in MOWHTO that has the benefit of optimizing surgical accuracy while providing early and consistent pain relief after surgery.

The application of 3D brachytherapy in cervical stump cancer: A retrospective study.

Cervical stump cancer is a carcinoma that grows on the cervical stump after a sub-total hysterectomy. There have been no studies on the application of 3D brachytherapy in cervical stump cancer. In the present study, we aimed to compare the curative effects, toxicity, and dosimetry of 3D and 2D brachytherapy in cervical stump cancer. Thirty-one patients admitted between 2012 and 2021, who were concurrently treated with intensity-modulated radiation therapy and brachytherapy for cervical stump cancer were divided into three groups according to the brachytherapy techniques: 2D brachytherapy, 3D image-guided brachytherapy (3D-IGBT), and 2D + 3D. For patients undergoing 2D brachytherapy and 3D-IGBT, data on survival, complications, and dose to target area or organs at risk (OARs) were collected and compared. Furthermore, dosimetry difference was investigated by reconstructing the 2D plan into a 3D plan. The median follow-up duration of all patients was 58 months. The overall 5-year progression-free survival, overall survival, and local control rates were 69.6%, 90.2%, and 78.2%, respectively. Late complications in the rectum, sigmoid colon, and bladder were milder in 3D brachytherapy than in 2D brachytherapy. Concerning the D90 value of clinical target volume (CTV) and D2cm3 value of OARs in EQD2, the 3D brachytherapy provided a lower dose to CTV (76.5 Gy vs. 95.9 Gy, on average) and OARs compared with 2D brachytherapy. Despite lacking statistical significance, 3D brachytherapy showed better outcomes regarding late toxicity than 2D brachytherapy, owing to the lower dose coverage in the bladder, rectum, sigmoid colon, and small intestine.

RTSA With Humeral Head Autograft Glenoid Reconstruction

Background: Untreated chronic massive rotator cuff tears and primary osteoarthritis can lead to conditions of significant retroversion, posterior bone loss, and humeral head subluxation. Indications: Reverse total shoulder arthroplasty with humeral head autograft glenoid reconstruction may be indicated in patients with advanced glenohumeral osteoarthritis and/or severe glenoid retroversion/bone loss due to rotator cuff arthropathy, trauma, primary, or inflammatory osteoarthritis. Technique: Besides routine radiography and preoperative computed tomography (CT) scans, 3-dimensional (3D) planning software is often performed as a routine part of preoperative planning. A 3D printed model of the glenoid can also be helpful in cases of significant bone deformity. Patients are placed in a 45° modified beach chair position. Using a standard deltopectoral approach, the glenoid is exposed. An anatomic humeral head resection is made. The contour of the articular margin of the humeral head should match the glenoid bone deficiency anatomically as it has been chronically resting within the glenoid defect. Three dimensional preoperative planning and the 3D printed model are used to make an asymmetric humeral head autograft which should match the deficiency perfectly. The articular cartilage is removed with a burr. The graft and baseplate are coupled together (metaphyseal bone facing the baseplate and prepared articular side of the graft facing native bone) and measurements are performed with the preoperative planning software to fashion a graft with the appropriate dimension and with the desired amount of lateralization. The bone graft is then compressed with the baseplate to the native glenoid and fixed with screws. Results: In select patients with careful preoperative planning, excellent outcomes can be achieved with careful gradual resumption of range of motion and strength with physical therapy. Sequential radiographic imaging is performed up to 6 months and beyond to confirm solid union of graft to native glenoid bone and incorporation into the baseplate. Discussion/Conclusion: Reverse total shoulder arthroplasty (rTSA) with humeral head autograft glenoid reconstruction is an excellent option to address severe glenoid bone loss and restore the native joint line for both primary osteoarthritis and rotator cuff arthropathy. Using 3D CT scans, 3D preoperative planning software and 3D printing of the glenoid can help achieve a good outcome. Patient Consent Disclosure Statement: The author(s) attests that consent has been obtained from any patient(s) appearing in this publication. If the individual may be identifiable, the author(s) has included a statement of release or other written form of approval from the patient(s) with this submission for publication.

BIM dimensions: example of air blower station at wastewater treatment plant

The main goal of research is to analyse the prospects for the development of BIM dimensions (3D-7D) in Russia on the example of Water and wastewater industry (WWI) asset. Justification of goal is the insufficient development of industry-specific BIM systems, allowing for different interpretations of its dimensions. The object of research is the air blower station (ABS), the most energy-intensive asset, which typically consumes 62-85% of the energy of WWTP’s. The method is a hypothesis of 3D-7D modeling of water utility asset, presented for the discussions. ABS compressors reduce costs by regulating the air supply due to lifestyle of the population and seasonal environmental conditions (example of simulation results is present). 3D design visualises variant of the reconstruction of the ABS, implemented according to typical project. 4D planning represent the schedule of energy service company, which provides investments and jobs for: design documentation execution, equipment purchase, installation and commissioning of equipment. 5D costs analyses features of the phase in terms of project expertise. 6D sustainability model in practice differs from prediction or forecasting generated by the simulation model of ABS asset, power consumption will be lower up to real (not simulated) technological loads. 7D management analyses possibility of the life cycle cost estimation as strategic advantage of WWI standard. The paper is based on Russian standards. Designing of 3D models are developing on an irregular basis (proactively) in Russia. The mastering of modeling 3D, 4D, 5D based on individual disciplines (as autonomous databases) is self-sufficient today as WWI tusk. The operational nature of WWI enterprises testifies to the development of elements of 6D-7D models.

Proximal humerus fracture sequelae: are corrective osteotomies still a taboo? The role of three-dimensional preoperative planning and patient-specific surgical guides for proximal humerus corrective osteotomy in combination with reverse shoulder arthroplasty.

Symptomatic proximal humeral fracture sequelae (PHFS) represent a surgical challenge due to the altered bone and soft tissue morphology. The purpose of this study was to report the outcome of Multiplanar Corrective Humeral Osteotomies (MCHOs) in combination with reverse total shoulder arthroplasty (rTSA) performed following a three-dimensional (3D) preoperative planning and using a 3D-printed patient-specific surgical instrumentation (PSI) in type 1C, 1D, and 4 PHFS. In this prospective monocentric study, we enrolled patients affected by symptomatic PHFS type 1C, 1D, or 4 of Boileau's classification, treated between 2018 and 2019 with rTSA associated to MCHO and followed-up at 12 and 24 mo. The preoperative and postoperative Constant Score (CS), visual analog scale, and Disabilities of the Arm, Shoulder and Hand (DASH) score were recorded. All patients underwent a preoperative computed tomography, then a dedicated software was used to run a segmentation algorithm on computed tomography images. Metaphyseal bone cuts were virtually performed before surgery in all patients, and a 3D-printed PSI was used to reproduce the planned osteotomies invivo. Twenty patients completed a 2-y follow-up. The mean (± standard deviation) CS, visual analog scale, and DASH values improve from 24.3 (± 8.8), 6.5 (± 1.3), 60.7 (± 9.6) preoperatively, to 67.7 (± 11.4), 1.6 (± 0.8), 24.1 (± 13.1) points after surgery, respectively. The minimally clinical important difference for CS and DASH score was achieved in 95% of patients. No major complication was observed. One patient showed an unexplained worsening of clinical scores between the 12 and the 24-mo follow-up, while in one patient bone resorption of the greater tuberosity was observed on radiographs at 2 y, with no clinical impact. The combination of preoperative 3D planning and intraoperative use of 3D-printed PSI to perform MCHO as concurrent procedure in the context of rTSA in the treatment of Boileau type 1C, 1D, and 4 PHFS may lead to a satisfactory clinical outcome at 2 y of follow-up.

A new three-dimensional patient-specific cutting guide for opening wedge high tibial osteotomy based on ct scan: preliminary in vitro results

PurposeThe aim of this study was to evaluate the accuracy of a patient-specific cutting guide on both coronal and sagittal alignment compared to the pre-operative planning in OWHTO.MethodsTwelve OWHTO on 6 cadaveric specimens were performed by 3 experienced knee surgeons using patient-specific cutting guides based on 3D pre-operative planning. Since the specimens had no major deformities, a fixed correction of 6° on the left and 10° on the right legs were carried out to simulate different scenarios. A pre-operative and post-OWHTO 3D CT scans were performed, and images were superimposed using the dedicated 3D planning software to align their reference axes. A pre-operative planning was performed considering both Medial Proximal Tibial Angle (MPTA) and Posterior Tibial Slope (PTS), and a patient-specific cutting guide was produced. Planned and post-OWHTO MPTA and PTS were evaluated (mean and standard deviation), and Pearson’s correlation coefficient was calculated to assess precision and accuracy of the whole treatment.ResultsA mean correction of 6,1° (SD 1,9°) and 1,2° (SD 1°) was obtained respectively in the coronal plane (MPTA) and in the sagittal plane (PTS). The average difference between planned and post-OWHTO MPTA and PTS was respectively 1,2° (SD 0,6°) and 1,2° (SD 1°) in the sagittal plane (PTS). Pearson’s correlation coefficient demonstrated a good accuracy of the treatment in both coronal and sagittal plane (respectively r=0,95 and r=0,86). No lateral hinge fractures were detected at the post-operative CT scan.ConclusionOWTHO performed with the help of 3D patient specific cutting guide on cadaveric specimens demonstrated good accuracy and reliability in obtaining the planned correction. In vivo studies are necessary to confirm these results and evaluate cost-effectiveness of this system.Level of evidenceLevel IV cadaveric study.

THE USE OF SURGICAL SUTURE AS AN IMPLANT PLACEMENT GUIDE – A RETROSPECTIVE OVER VIEW OF OVER TWO DECADES OF IMPLANT THERAPY

In the era of digital dentistry, positioning of implants can by designed with the help of CBCT and CAD CAM. Surgical guide can be made to direct the implant placement in bone. Although various researchers showed the importance of 3D planning but because of chances of errors at various levels of digital protocols may lead to deviations. Even no data is available to confirm the accuracy of GBR with digital workflow. This retrospective analysis of simple suture placement technique in anterior edentulous region will make clinicians to understand the positioning of drills, anatomical variations, directions and placements of implants, need of bone grafting and implant emergence.

3D MODELING OF GRASSLANDS THROUGH GNSS TECHNOLOGY

Monitoring and 3D modeling of an objective can only be done on the basis of high-precision topo-geodetic measurements, but also on the basis of UAV (drone) technologies, thus resulting in an overview of a certain study area. In this context, the present work aims to develop the creation of the 3D model of a grassland surface following a topographic survey by means of GNSS technology and specialized programs. This topographic survey was carried out with the Leica Viva GS07 GNSS equipment, an instrument that contains a wide range of applications. In this work, I used the Real Time Kinematic method to determine the points based on which I created the 3D model in AutoCAD using the TopoLT program. Because the data obtained is complex, in addition to 2D plans, we also have information that can be analyzed in 3D. For studies regarding the shape and the way of exploitation of the land, we created a digital model of the land which is the 3D digital representation of the respective surface. Based on the digital terrain model, we can easily visualize the relief of the grassland, in the present case the minimum altitude is 572.50 m, and the maximum altitude is 590.00 m, with a level difference of 17.5 m over the entire area. This digital terrain model can also be used to model water flow or other geomorphological processes that occur in the analyzed grassland (landslides, erosion, etc.). Multiple longitudinal or transversal profiles can be created over the entire surface to better observe the relief of the land.

Predictive modelling for late rectal and urinary toxicities after prostate radiotherapy using planned and delivered dose.

Normal tissue complication probability (NTCP) parameters derived from traditional 3D plans may not be ideal in defining toxicity outcomes for modern radiotherapy techniques. This study aimed to derive parameters of the Lyman-Kutcher-Burman (LKB) NTCP model using prospectively scored clinical data for late gastrointestinal (GI) and genitourinary (GU) toxicities for high-risk prostate cancer patients treated using volumetric-modulated-arc-therapy (VMAT). Dose-volume-histograms (DVH) extracted from planned (DP) and accumulated dose (DA) were used. DP and DA obtained from the DVH of 150 prostate cancer patients with pelvic-lymph-nodes irradiation treated using VMAT were used to generate LKB-NTCP parameters using maximum likelihood estimations. Defined GI and GU toxicities were recorded up to 3-years post RT follow-up. Model performance was measured using Hosmer-Lemeshow goodness of fit test and the mean area under the receiver operating characteristics curve (AUC). Bootstrapping method was used for internal validation. For mild-severe (Grade ≥1) GI toxicity, the model generated similar parameters based on DA and DP DVH data (DA-D50:71.6 Gy vs DP-D50:73.4; DA-m:0.17 vs DP-m:0.19 and DA/P-n 0.04). The 95% CI for DA-D50 was narrower and achieved an AUC of >0.6. For moderate-severe (Grade ≥2) GI toxicity, DA-D50 parameter was higher and had a narrower 95% CI (DA-D50:77.9 Gy, 95% CI:76.4-79.6 Gy vs DP-D50:74.6, 95% CI:69.1-85.4 Gy) with good model performance (AUC>0.7). For Grade ≥1 late GU toxicity, D50 and n parameters for DA and DP were similar (DA-D50: 58.8 Gy vs DP-D50: 59.5 Gy; DA-n: 0.21 vs DP-n: 0.19) with a low AUC of<0.6. For Grade ≥2 late GU toxicity, similar NTCP parameters were attained from DA and DP DVH data (DA-D50:81.7 Gy vs DP-D50:81.9 Gy; DA-n:0.12 vs DP-n:0.14) with an acceptable AUCs of >0.6. The achieved NTCP parameters using modern RT techniques and accounting for organ motion differs from QUANTEC reported parameters. DA-D50 of 77.9 Gy for GI and DA/DP-D50 of 81.7-81.9 Gy for GU demonstrated good predictability in determining the risk of Grade ≥2 toxicities especially for GI derived D50 and are recommended to incorporate as part of the DV planning constraints to guide dose escalation strategies while minimising the risk of toxicity.

Pre-operative arthritic glenoid assessment: 3D automated planning software versus manual multiplanar measurements of version and inclination

BackgroundPreoperative CT-based planning is established in shoulder arthroplasty surgery. Automated planning software has become available to assist the surgeon and may increase reliability and efficiency. This study aims to evaluate the reliability of an automated 3-dimensional (3D) planning software package (Blueprint™ v2.1.5, Wright Medical Ltd) in the assessment of the arthritic shoulder against manual multiplanar measurement (MM). Methods74 CT studies acquired for preoperative shoulder arthroplasty planning were reviewed on two occasions by four different evaluators, taking manual measurement (MM) of glenoid version and inclination adjusted with multiplanar reformation and adhering to modified Freidman and Maurier methods. 15 scans were not processed by Blueprint due to incompatible scanning protocols or severe scapular dysmorphia. 59 Blueprint measures were compared with the manual data. ResultsVersion: Intra-observer reliability of glenoid version MM was excellent (mean ICC 0.92). Inter-observer reliability between all four readers was good (ICC 0.89). A Bland-Altman analysis of Blueprint versus MM for version measurements demonstrated a mean pair difference of −5.77 (95% CI -7.25 to 4.29). Inclination: Intra-rater and inter-rater reliabilities were good (ICC 0.85 and 0.80 respectively). Blueprint and MM values for inclination followed a more convergent pattern than for version. Bland-Altman analysis for inclination did not show substantial bias, with a mean pair difference of 1.4 (95% CI -0.1 to 2.9) ConclusionManual preoperative planning for shoulder arthroplasty is time consuming and requires experience. Automated 3D planning offers a consistent tool to assist the surgeon, notwithstanding intra-operative anatomical and technical variation, and margin of error. Surgeons should as ever be mindful of the specifics of a given automated program and our data quantified a bias for retroversion which may be important for measures close to the thresholds for augmentation or customised implants.

Use of 3D planning of HDR brachytherapy in patients with cervical cancer

Background. Combined radiation therapy is the «gold standard» for the treatment of stages IIB-IVA of cervical cancer (cervical cancer). Given the data of statistical indicators of cervical cancer, the study of new approaches to treatment and implementation in clinical practice of modern technologies of radiation therapy of widespread cervical cancer is an extremely important area.&#x0D; Purpose – evaluate the benefits of using CT topometric preparation in planning brachytherapy for cervical cancer.&#x0D; Materials and Methods. 3D planning of brachytherapy of 24 patients with locally advanced cervical cancer (FIGO IIIB stage), who underwent a radical program of combined radiation therapy (remote radiation therapy with chemical modification with cisplatin followed by HDR-brachytherapy (High dose rate brachytherapy)).&#x0D; Results. The paper presents the results of the analysis of differences in brachytherapy planning according to orthogonal images and CT images. The analysis of the influence of the constitutional features of patients revealed that there are differences in the topographic anatomy of the pelvis depending on the surface area of the body. In patients with a body surface area of up to 1,65 m2 , a more intimate fit of the intestine to the target volume of irradiation was noted. No similar planning difficulties were found in patients with a body surface area above 1,65 m2 .&#x0D; Conclusions. The use of 3D images in the planning of intracavitary irradiation in patients with cervical cancer provides precision brachytherapy by simultaneously visualizing the irradiated volumes and spatial relationships of the anatomical structures of the pelvis, the introduced endostats and the corresponding volumetric dose distributions.

Implications of navigation system use for glenoid component placement in reverse shoulder arthroplasty

Recently, three-dimensional (3D) planning, patient-specific instruments, and navigation system have been developed to improve the accuracy of baseplate placement in reverse shoulder arthroplasty (RSA). The purpose of this study was to evaluate baseplate placement using the navigation system. Sixty-four shoulders in 63 patients who underwent RSA for rotator cuff tear arthropathy or irreparable rotator cuff tears were enrolled. Conventional RSA was performed in 31 shoulders and navigated RSA using pre-operative planning software was performed in 33 shoulders. The use of augmented baseplates, the version and inclination of the baseplate, and screw length were compared between conventional RSA and navigated RSA. Augmented baseplates were used more frequently in navigated RSA than in conventional RSA (20 vs 9 shoulders, p = 0.014). Baseplate alignment was 1.0° (SD 5.1) of retroversion and 2.4° (SD 6.8) of superior inclination in conventional RSA and 0.2° (SD 1.9) of anteversion and 0.3° (SD 1.7) of superior inclination in navigated RSA. Compared with conventional RSA, precision of baseplate version and inclination were higher in navigated RSA (both p < 0.001). Superior, inferior, and posteroinferior screws were significantly longer in navigated RSA than in conventional RSA (p = 0.021, 0.001 and < 0.001, respectively). Precision of superior and inferior screw lengths was significantly higher in navigated RSA than in conventional RSA (both p = 0.001). Our results suggest that adoption of pre-operative planning software increased augmented baseplate use to minimize the glenoid reaming. The navigation system allows placement of the baseplate accurately, according to the pre-operative plan. Furthermore, the navigation system enables monitoring of screw length and direction in real time.

Physician-modified endograft using three-dimensional model-assisted planning.

Case-specific and true-to-scale three-dimensional (3D) models have become increasingly useful tools for physician-modified endovascular grafting. This study aimed to validate the use of 3D model-assisted planning for fenestration design. Thirty-two consecutive patients (2019-2021) presenting with pararenal or juxtarenal abdominal aortic aneurysm (n= 16), paravisceral abdominal and Crawford's extent IV thoracoabdominal aortic aneurysm (n= 12), and type I endoleak after endovascular repair (n= 4) were analyzed retrospectively. All cases were planned manually with a standard method using curved planar reconstruction stretch images and multiplanar images perpendicular to the centerlines. The design was finalized by intraoperative 3D model-assisted planning. Intermethod agreements were assessed for geometrical relationships (separation heights and angles) between the superior mesenteric and renal arteries. The datasets from 55 double measurements of the entire cohort in this series were used to assess measurement discrepancies (≥3mm separation height or ≥15° angle difference) and fenestration mismatches (≥3mm separation between the manually planned and 3D model-assisted-planned renal arterial centers on the device surface) between manual and 3D model-assisted planning. Statistical analyses were performed to test the impact of anatomical factors on the discrepancies and mismatches. The imposition accuracy of 3D model-assisted planning and short-term clinical results of the 32 cases were also evaluated. Fourteen fenestration measurement discrepancies were detected. The size of the stent graft (P= .0381), the aortic angle (P= .0008), and the prior existence of stent graft (P= .0123) were found to have a statistically significant impact on the measurement discrepancy, using single logistic and Fisher's exact tests. Twelve fenestration mismatches were observed and found to be significantly affected (P= .0039) by aortic angle. A cutoff value for fenestration mismatch was found to be 36.5°, with a sensitivity and specificity of 69.2% and 80.5%, respectively, using receiver operating characteristic analysis (area under the curve, 0.782± 0.081; P= .0023). A high level of branch preservation (100%) was achieved. During the observation period (1.3years on average; range, 0.5-2.5years), no patient experienced complications related to fenestration. The differences between the planning methods were non-negligible. However, 3D model-assisted planning increased the precision of the fenestration design when the conformation of the stent graft to the aortic anatomy is taken into account.

Difference analysis of the glenoid centerline between 3D preoperative planning and 3D printed prosthesis manipulation in total shoulder arthroplasty.

Excessive version and inclination of the glenoid component during total shoulder arthroplasty can lead to glenohumeral instability, early loosening, and even failure. The orientation and position of the central pin determine the version and inclination of the glenoid component. The purpose of this study was to compare the differences in centerline position and orientation obtained using "3D preoperative planning based on the best-fit method for glenoid elements" and the surgeon's manipulation. Twenty-nine CT images of glenohumeral osteoarthritis of the shoulder were reconstructed into a 3D model, and a 3D printer was used to create an in vitro model for the surgeon to drill the center pin. The 3D shoulder model was also used for 3D preoperative planning (3DPP) using the best-fit method for glenoid elements. The in vitro model was scanned and the version, inclination and center position were measured to compare with the 3DPP results. The respective mean inclinations (versions) of the surgeon and 3DPP were -2.63° ± 6.60 (2.87° ± 5.97) and -1.96° ± 4.24 (-3.21° ± 4.00), respectively. There was no significant difference in the inclination and version of the surgeon and 3DPP. For surgeons, the probability of the inclination and version being greater than 10° was 13.8% (4/29) and 10.3% (3/29), respectively. Compared to the 3DPP results, the surgeon's center position was shifted down an average of 1.63mm. There was a significant difference in the center position of the surgeon and 3DPP (p < 0.05). The central pin drilled by surgeons using general instruments was significantly lower than those defined using 3D preoperative planning and standard central definitions. 3D preoperative planning prevents the version and inclination of the centerline from exceeding safe values (± 10°).

Clinical treatment planning for kilovoltage radiotherapy using EGSnrc and Python.

Kilovoltage radiotherapy dose calculations are generally performed with manual point dose calculations based on water dosimetry. Tissue heterogeneities, irregular surfaces, and introduction of lead cutouts for treatment are either not taken into account or crudely approximated in manual calculations. Full Monte Carlo (MC) simulations can account for these limitations but require a validated treatment unit model, accurately segmented patient tissues and a treatment planning interface (TPI) to facilitate the simulation setup and result analysis. EGSnrc was used in this work to create a model of Xstrahl kilovoltage unit extending the range of energies, applicators, and validation parameters previously published. The novel functionality of the Python-based framework developed in this work allowed beam modification using custom lead cutouts and shields, commonly present in kilovoltage treatments, as well as absolute dose normalization using the output of the unit. 3D user-friendly planning interface of the developed framework facilitated non-co-planar beam setups for CT phantom MC simulations in DOSXYZnrc. The MC models of 49 clinical beams showed good agreement with measured and reference data, to within 2% for percentage depth dose curves, 4% for beam profiles at various depths, 2% for backscatter factors, 0.5 mm of absorber material for half-value layers, and 3% for outputfactors. End-to-end testing of the framework using custom lead cutouts resulted in good agreement to within 3% of absolute dose distribution between simulations and EBT3 GafChromic film measurements. Gamma analysis demonstrated poor agreement at the field edges which was attributed to the limitations of simulating smooth cutout shapes. Dose simulated in a heterogeneous phantom agreed to within 7% with measured values converted using the ratio of mass energy absorption coefficients of appropriate tissues andair.