The tortuous course of the anterior ethmoidal artery in the orbit: A cadaveric study.

AIM: The study aimed to define the coursing pattern of the anterior ethmoidal artery in the orbit to minimize complications during endoscopic interventions. MATERIALS AND METHODS: A total of ten formalin-fixed cadaveric halves were included in the study. Orbital regions were shown with a superior approach. The superior rectus and superior oblique muscles, as well as the connective tissue and vessels were removed to observe the path of the anterior ethmoidal artery. Measurements such as the width of the artery, the anterior-posterior length of the U formation, the length of the intraorbital part of the ophthalmic artery, and the distance of the AEA from its opthalmic origin to the anterior ethmoidal foramen were made. RESULTS: Ten of the AEAs originated from the ophthalmic artery. The AEA branches originated from the ophthalmic artery approximately 18.4 mm after the orbital artery entered the orbital, and the mean width of the AEAs was 0.82 mm. In seven of the total anterior ethmoidal arteries, they coursed in the intraethmoidal cavities below the cranial base. The mean distance from the origin of AEAs to the medial wall of the orbit was 4.9 mm. After leaving the ophthalmic artery, seven of the AEAs were coursing forward and turned back ('U' turn formation), which have proximately 1.5 mm in anteroposterior direction. CONCLUSION: The anterior ethmoidal artery is 0.8 mm wide, originates from the distal part of the ophthalmic artery, entering the orbit after a 1.5 mm U-turn.

The Upper Attachment of the Uncinate Process and Anterior Ethmoidal Artery.

OBJECTIVE: Variations in the upper attachment of the uncinate process (UP) are important because they can affect frontal sinus drainage and change the morphology. Functional endoscopic sinus surgery (FESS) is the primary technique used to treat chronic medically refractory rhinosinusitis. Uncinectomy is the basis of FESS technique to obtain the best possible result from surgery. The anterior ethmoidal artery (AEA) enters the nasal cavity through the orbital medial wall (lamina papyracea) may also be affected by the upper attachment of the UP. The aim of this study was to investigate a possible link between UP variations and the course of the AEA. MATERIALS AND METHODS: This retrospective, computed tomography (CT)-based, anatomic study was conducted on 200 healthy adults (100 females and 100 males) by screening bilateral paranasal sinus images. The upper attachment of the UP was classified in 6 types (1-6) based on the Liu classification. The AEA was divided into 4 types (A-D) based on location: anterior to the frontal sinus (A), between the frontal sinus and the middle nasal turbinate (B), and anterior to the posterior ethmoidal cells (C and D). All the CT images were evaluated simultaneously by 2 anatomists and 1 radiologist. RESULTS: Of the total cases (200 right and 200 left side), 48.8% were type 1 UP attachment, 11.0% type 2, 12% type 3, 9% type 4, 18% type 5, and 1.2% type 6. The AEAs were classified as 12.2% type A, 71.8% type B, 15.2% type C, and 0.8% type D. CONCLUSION: The course of the AEA through the nasal cavity was observed to shift anteriorly from the ethmoidal bulla to the frontal sinus in patients with UP attached to the lamina papyracea and middle turbinate. Remarkably, the AEA always coursed anterior from the middle nasal turbinate line.

Prespecialist perceptions of three-dimensional heart models in anatomical education.

PURPOSE: This article aims to discuss the use of three-dimensional (3D) printed models of vascular variation cases as an educational tool for undergraduate and postgraduate anatomy students. METHODS: This advanced study involved ten anatomy assistants who were provided with five distinct cases of congenital cardiovascular variations, each accompanied by a computed tomography angiography (CT-A) and 1:1 solid model format. The residents were asked to generate perceptions for both formats and then compare these perceptions based on identifying the variation, defining the structural features, and evaluating relevant educational perspectives. RESULTS: The vascular origin measurement values compared to the statistically evaluated real values of the related cases showed that models were 1:1 identical copies. Qualitative assessment feedback from five stations supported the usefulness of 3D models as educational tools for organ anatomy, simulation of variational structures, and overall medical education and anatomy training. Models showcasing different anatomical variations such as aortic arch with Type 2 pattern, a right-sided aortic arch with Type 2 pattern, an aberrant right subclavian artery, arteria lusoria in thorax, and a left coronary artery originating from pulmonary trunk in an Alcapa type pattern allow for better analysis due to their complex anatomies, thus optimizing the study of variation-specific anatomy. The perception level in the 3D model contained higher points in all of the nine parameters, namely identification of cardiovascular variations, defining the vessel with anomaly, aortic arch branch count and appearance order, feasibility of using it in peers and student education. 3D models received a score 9.1 points, while CT-A images were rated at 4.8 out of 10. CONCLUSION: 3D printed anatomical models of variational cardiovascular anatomy serve as essential components of anatomy training and postgraduate clinical perception by granting demonstrative feedback and a superior comprehension of the visuospatial relationship between the anatomical structures.

Patient-specific three-dimensional printing spine model for surgical planning in AO spine type-C fracture posterior long-segment fixation.

OBJECTIVE: The aim of this study was to compare duration of surgery, intraoperative fluoroscopy exposure, blood loss and the accuracy of pedicular screw placement between 3D model-assisted surgery and conventional surgery for AO spinal C-type injuries. METHODS: In this study 32 patients who were admitted with thoracolumbar AO spinal C-type injuries were included. These patients were divided randomly into two groups of 16 where one group was operated on using conventional surgery and the other group was operated on using 3D model-assisted surgery. During surgery, instrumentation time, amount of blood loss and intraoperative fluoroscopy exposure were recorded. Moreover, the status of the screws in the pedicles was assessed as described by Learch and Wiesner's and regional sagittal angles (RSA) were measured preop and postoperatively. RESULTS: It was found that there was a statistically significant difference in instrumentation time, blood loss and intraoperative fluoroscopy exposure in the 3D model-assisted surgery group (61.9 ± 4.7 min, 268.4 ± 42.7 ml, 16.3 ± 1.9 times) compared to the conventional surgery group (75.5 ± 11.0 min, 347.8 ± 52.2 mL, 19.7 ± 2.4 times) (t=4.5325, P < 0.0001 and t=4.7109, P < 0.0001 and t=4.4937, P < 0.0001, respectively) Although the screw misplacement rate of the conventional surgery group was higher than that of the 3D model-assisted surgery group, the only statistically significant difference was in the medial axial encroachment (t=5.101 P=0.02) . There was no severe misplacement of pedicle screws in either group. There were no statistically significant differences between postoperative RSA angles and were in both groups restored significantly. CONCLUSION: The results of this study have shown us that the 3D model helps surgeons see patients' pathoanatomy and determine rod lengths, pedicle screw angles and lengths preoperatively and peroparatively, which in turn shortens operative time, reduces blood loss and fluoroscopy exposure. LEVEL OF EVIDENCE: Level I, Therapeutic Study.

Evaluation of the effects of using 3D - patient specific models of displaced intra - articular calcaneal fractures in surgery.

BACKGROUND: It was aimed to compare conventional surgery and three-dimensional (3D) model-assisted surgery used in the treatment of calcaneal fractures. MATERIALS & METHODS: A total of 37 patients with unilateral calcaneal fractures were randomly divided into two groups as a conventional surgery group (n: 19) and a 3D model-assisted surgery group (n: 18). The preoperative, postoperative and last follow up angles of the Bohler and Gissane, calcaneal width and facet height were measured. The duration of the operation, blood loss volume, fluoroscopy usage, instrumentation time for both groups were recorded. Finally, the follow-up AOFAS scores were evaluated. A questionnaire was used to determine the perceptions of the resident doctors about the 3D model. RESULTS: The duration of the operation, blood loss volume, fluoroscopy usage, instrumentation time for 3D model-assisted surgery group were 83.3 ± 4.6 minutes, 83.6 ± 4.6 ml, 6.8 ± 1.4 times and 13.0 ± 0.8 weeks, and as for conventional group they were 130.0 ± 5.8 minutes, 105.1 ± 5.6 minutes, 11.7 ± 1.5 ml, 22.2 ± 2.4 times and 13.3 ± 0.8 weeks, respectively (p < 0.0001). The both groups significantly restored Bohler angle, Gissane angle, calcaneal width and calcaneal facet height after operation (p < 0.0001). The 3D model-assisted group was significantly more succesful in restoration and protection of achieved correction of calcanel facet height (p < 0.0001). The difference was determined among the groups at the final follow-up examination with respect to the amount of change according the values achieved post-op. were significant in Bohler angle (p < 0.001), calcaneal facet height (p < 0.0001) and calcaneal widht (p = 0.017). There was no significant difference between AOFAS scores of the two groups at last follow-up. Resident doctors exhibited high scores of overall satisfaction with the use of a 3D printing model. CONCLUSIONS: Compared to the conventional group, the 3D model-assisted group provide successful intervention and reduce operation, instrumentation time and the fluoroscopy usage with less blood loss. Performing 3D-assisted surgery helps the quality of reduction during the surgery and stability of internal fixation to protect achieved reduction at follow-up more succesfully.

Variations of the extracranial segment of vertebral artery as a bleeding risk factor.

BACKGROUND: Standart interventional procedures such as screw instrumentation, aortic arch endovascular surgery and cervical nerve blockade may be of fatal risk due to anatomic reason of variations in the proximal part of the vertebral artery (VA). The aim of this study is to study the VA variations of the extracranial segments to evaluate the frequency of the incident to demonstrate the importance of clinical condition strategy. METHODS: The prevalence of variations and morphometric measurements of the VA in three-dimensional computed tomographic angiography (3D-CTA) scans were studied. Total 400 VA was investigated for the aortic arch origin of the VA, diameter of the VA, its level of entry into the transverse foramen, the dominance sides, and related basilar artery course. RESULTS: 3D-CTA radiographs of 200 Anatolian patients (120 men and 80 women with age range 17-90 years). In most cases (approximately 94%), both sides of VA were the first branch of subclavian artery. While all the right VAs was branched from the subclavian artery, 6% of the left VAs were branched from the aortic arch. 2/3 of them originated from the proximal of the subclavian artery and 1/3 from the distal. The VA which were originating from the proximal of the classical anatomic pattern tended to enter the transverse foramen more distally than C6 level. VAs with a different level of entry than C6 are left-sided and aortic arch originated (out of 8 cases 3 had a level of entry at C5 and 2 at C4). The outer diameter ranges of the prevertebral part of the VA of subclavian origin and left VA of aortic arch origin were 3.2-3.6 mm and 3.2-3.6 mm, respectively. While the diameters of the right and left VAs were almost the same in approximately 20% cases, the left VA was dominant in up to 60% of cases. A significant relationship was found between the side of the dominant VA and in the course of the basilar artery. CONCLUSIONS: The relationship between the dominant side of VA and the course of the basilar artery of its own vessel has never been reported elsewhere. Such anatomical variations, routine preoperative 3D-CTA evaluation is mandatory to prevent the VA injury when C5-C2 instrumentation, anterior cervical decompression, cervical nerve blockade and aortic arch surgery are planned.

Patient-centered oncosurgical planning with cancer models in subspecialty education.

BACKGROUND: A fundamental aspect of oncosurgical planning in organ resections is the identification of feeder vessel details to preserve healthy organ tissue while fully resecting the tumors. The purpose of this study was to determine whether three-dimensional (3D) cancer case models of computed tomography (CT) images will assist resident-level trainees in making appropriate operative plans for organ resection surgery. METHODS: This study was based on the perception of surgery residents who were presented with 5 different oncosurgical scenarios. A five-station carousel including cases of liver mass, stomach mass, annular pancreas, pelvic mass and mediastinal mass was formed for the study. The residents were required to compare their perception level of the cases with their CT images, and 3D models in terms of identifying the invasion of the mass, making differential diagnosis and preoperative planning stage. RESULTS: All residents have given higher scores for models. 3D models provided better understanding of oncopathological anatomy and improved surgical planning. In all scenarios, 70-80% of the residents preferred the model for preoperative planning. For surgical choice, compared to the CT, the model provided a statistically significant difference in terms of visual assessment, such as tumor location, distal or proximal organotomy (p:0.009). In the evaluation of presacral mass, the perception of model was significantly better than the CT in terms of bone-foramen relationship of chondrosarcoma, its origin, geometric shape, localization, invasion, and surgical preference (p:0.004). The model statistically significantly provided help to evaluate and prepare the case together with the colleagues performing surgery (p:0.007). Commenting on the open-ended question, they stated that the tumor-vessel relationship was clearly demonstrated in the 3D model, which has been very useful. CONCLUSIONS: With the help of 3D printing technology in this study, it is possible to implement and evaluate a well-structured real patient scenario setup in cancer surgery training. It can be used to improve the understanding of pathoanatomical changes of multidisciplinary oncologic cases. Namely, it is used in guiding the surgical strategy and determining whether patient-specific 3D models change pre-operative planning decisions made by surgeons in complex cancer mass surgical procedures.

Perceptions of porta-celiac vascular models for hepatic surgery and their use in residency training.

BACKGROUND: Primary aspect of hepatic navigation surgery is the identification of source vascular details to preserve healthy liver which has a vascular anatomy quite challenging for the young surgeons. The purpose was to determine whether three-dimensional (3D) vascular pattern models of preoperative computed tomography (CT) images will assist resident-level trainees for hepatic surgery. METHODS: This study was based on the perception of residents who were presented with 5 different hepatic source vascular patterns and required to compare their perception level of CT, and 1:1 models in terms of importance of variability, differential of patterns and preoperative planning. RESULTS: All residents agree that models provided better understanding of vascular source and improved preplanning. Five stations provided qualitative assessment with results showing the usefulness of porta-celiac models when used as anatomical tools in preplanning (p = 0.04), simulation of interventional procedures (p = 0.02), surgical education (p = 0.01). None of the cases had scored less than 8.5. Responses related to understanding variations were significantly higher in the perception of the 3D model in all cases, furthermore 3D models were more useful for seniors in more complex cases 3 and 5. Some open-ended answers: "The 3D model can completely change the operation plan" One of the major factors for anatomical resection of liver transplantation is the positional relationship between the hepatic arteries and the portal veins. CONCLUSION: The plastic-like material presenting the hepatic vascularity enables the visualization of the origin, pattern, shape, and angle of the branches with appropriate spatial perception thus making it well-structured.

Three-Dimensional Printed Anatomical Models Help in Correcting Foot Alignment in Hallux Valgus Deformities.

BACKGROUND: Hallux valgus (HV) is the most common pathologic entity affecting the great toe. The goal of corrective surgery is to restore foot mechanics and provide pain relief. The purpose of the study was to create individual angle using life-size foot models with three-dimensional (3D) printing technology to design a section on HV osteotomy. MATERIALS AND METHODS: Ten female patients with a diagnosis of HV were included. Radiologic [HV angle and intermetatarsal (IM) angle] and clinical [American Orthopaedic Foot and Ankle Score (AOFAS)] assessment was done pre- and postoperatively. All the operations were planned together with 3D life-size models generated from computed tomography (CT) scans. Benefits of using the 3D life-size models were noted. The 3D model's perception was evaluated. RESULTS: The mean AOFAS score, mean HV, and IM angles had improved significantly (P < 0.05). The visual and tactile inspection of 3D models allowed the best anatomical understanding, with faster and clearer comprehension of the surgical planning. At the first tarsometatarsal joint, the HV models showed significantly greater dorsiflexion, inversion, and adduction of the first metatarsal relative to the medial cuneiform. At the first metatarsophalangeal joint, the HV models showed significantly greater eversion and abduction of the first proximal phalanx relative to the first metatarsal. It provided satisfactory results about operation time and blood loss. 3D model's perception was statistically significant (P < 0.05). CONCLUSION: 3D models help to transfer complex anatomical information to clinicians, which provide guidance in the preoperative planning stage, for intraoperative navigation. It helps to create a patient-specific angle section on osteotomy to correct IM angle better and improve postoperative foot function. The 3D personalized model allowed for a better perception of information when compared to the corresponding 3D reconstructed image provided.

Surgical planning with patient-specific three-dimensional printed pancreaticobiliary disease models - Cross-sectional study.

BACKGROUND: Three-dimensional (3D) printing has been increasingly used in medical applications with the creation of accurate patient-specific 3D printed models in medical imaging data. This study has been planned based on the fact that research on 3D printing in pancreaticobiliary disease is limited due to lack of studies on validation of model accuracy. METHODS: This is an innovative study where general surgery residents are presented 5 distinct hepatopancreatobiliary disease scenarios to generate a perception and required to compare their perception level of these cases with magnetic resonance cholangiopancreatography (MRCP), 3D images and 1:1 solid models that the pathology, diverse diagnosis and presurgery diagnosis stages can be observed. This study is single-centered. RESULTS: The dilated pancreaticobiliary intervention based on scenarios for general surgery residency was more original since there was no prior study that includes both model building and the evaluation of the perception created by the model. Five scenarios provided qualitative assessment with results showing the usefulness of 3D models when used as clinical tools in preoperative planning, simulation of interventional procedures, surgical education, and training. The perception level in the 3D model, MRCP (Z: 3.854, p: 0.000) and the 3D image (Z: 2.865, p: 0.004) was higher; likewise, the 3D-STL image was higher compared to the MRCP image (Z: 3.779, p: 0.000). All subspecialists agree that 3D models provided better understanding of dilated pancreaticobiliary pathoanatomy and improved surgical planning. CONCLUSIONS: A thoroughly outlined genuine patient situation layout aimed for general surgery training can be installed and monitored with the support of 3D printing technology of this study. This can be utilized to develop the comprehension of pathoanatomical variations of complex pancreaticobiliary illness and to adopt a surgical approach.

A retrospective comparison of the conventional versus three-dimensional printed model-assisted surgery in the treatment of acetabular fractures.

OBJECTIVE: The aim of this study was to compare the clinical and radiological outcomes of the conventional versus individualized three-dimensional (3D) printing model-assisted pre-contoured plate fixation in the treatment of patients with acetabular fractures. METHODS: The data from 18 consecutive patients who underwent surgery for the acetabular fractures were retrospectively analyzed. The patients were divided into two groups (9 in each): conventional and 3D printed model-assisted. The groups were then compared in terms of the duration of surgery, time of instrumentation, time of intraoperative fluoroscopy, and volume of blood loss. The quality of the fracture reduction was also evaluated postoperatively by radiography and computed tomography in both the groups. The quality of the fracture reduction was defined as good (<2 mm) or fair (>2 mm) based on the amount of displacement in the acetabulum. RESULTS: The conventional group included 9 patients (9 males; mean age=41.7 years; age range=16-70) with a mean follow-up of 11.9 months (range=8-15); the 3D printed model-assisted group consisted of 9 patients (9 males; mean age=46.2 years; age range=30-66) with a mean follow-up of 10.33 months (range=7-17). The average duration of surgery, mean time of instrumentation, time of intraoperative fluoroscopy, and mean volume of blood loss were 180.5±9 minutes, 36.2±3.6 minutes, 6±1 times, and 403.3±52.7 mL in the 3D printed model-assisted group, and 220±15.6 minutes, 57.4±10.65 minutes, 10.4±2.2 times, and 606.6±52.7 mL in the conventional group, respectively. Procedurally, the average duration of surgery, mean time of instrumentation, and mean time of fluoroscopy were significantly shorter, and the mean volume of blood loss was significantly lower in the 3D printed model-assisted group (p<0.05). The quality of the fracture reduction was good in 7 patients (78%) in the conventional group and 8 patients (89%) in the 3D printed model-assisted group. CONCLUSION: As compared with the conventional surgery, the 3D printing model-assisted pre-contoured plate fixation technique can improve the clinical and radiological outcomes of the acetabular fractures, with shorter surgery, instrumentation, intraoperative fluoroscopy times, and blood loss. LEVEL OF EVIDENCE: Level III, Therapeutic study.

Surgical advantages of using 3D patient-specific models in high-energy tibial plateau fractures.

PURPOSE: Treatment of tibial plateau fractures are difficult due to the intra-articular nature of the proximal tibia and extensive involvement of the soft tissue envelope. In this study, we investigated the surgical experience acquired using digitally designed life-size fracture models to guide as a template to place plates and screws in the treatment of tibial plateau fractures and anatomic reduction of joint. METHODS: 20 tibial plateau frature patients were divided into two equal surgery groups as conventional versus 3D model assisted. The fracture line angles, depression depth, and preoperative/postoperative Rasmussen knee score were measured for each patient. RESULTS: The duration of the operation, blood loss volume, turniquet time and number of intraoperative fluoroscopy was 89.5 ± 5.9 min, 160.5 ± 15.3 ml, 74.5 ± 6 min and 10.7 ± 1.76 times, for 3D printing group and 127 ± 14.5 min, 276 ± 44.8 ml, 104.5 ± 5.5 min and 18.5 ± 2.17 times for the conventional group, respectively. 3D model-assisted group indicated significantly shorter operation time, less blood loss volume, shorter turniquet and fluoroscopy times, and better outcome than the conventional one. CONCLUSIONS: The customized 3D model was user friendly, and it provided a radiation-free tibial screw insertion. The use of these models assisted surgical planning, maximized the possibility of ideal anatomical reduction and provided individualized information concerning tibial plateau fractures.

Building Three-Dimensional Intracranial Aneurysm Models from 3D-TOF MRA: a Validation Study.

To create realistic three-dimensional (3D) vascular models from 3D time-of-flight magnetic resonance angiography (3D-TOF MRA) of an intracranial aneurysm (IA). Thirty-two IAs in 31 patients were printed using 3D-TOF MRA source images from polylactic acid (PLA) raw material. Two observers measured the maximum IA diameter at the longest width twice separately. A total mean of four measurements as well as each observer's individual average MRA lengths were calculated. After printing, 3D-printed anatomic models (PAM) underwent computed tomography (CT) acquisition and each observer measured them using the same algorithm as applied to MRA. Inter- and intra-observer consistency for the MRA and CT measurements were analyzed using the intraclass correlation coefficient (ICC) and a Bland-Altman plot. The mean maximum aneurysm diameter obtained from four MRA evaluations was 8.49 mm, whereas it was 8.83 mm according to the CT 3D PAM measurement. The Wilcoxon test revealed slightly larger mean CT 3D PAM diameters than the MRA measurements. The Spearman's correlation test yielded a positive correlation between MRA and CT lengths of 3D PAMs. Inter and intra-observer consistency were high in consecutive MRA and CT measurements. According to Bland-Altman analyses, the aneurysmal dimensions obtained from CT were higher for observer 1 and observer 2 (a mean of 0.32 mm and 0.35 mm, respectively) compared to the MRA measurements. CT dimensions were slightly overestimated compared to MRA measurements of the created models. We believe the discrepancy may be related to the Laplacian algorithm applied for surface smoothing and the high slice thickness selection that was used. However, ICC provided high consistency and reproducibility in our cohort. Therefore, it is technically possible to produce 3D intracranial aneurysm models from 3D-TOF MRA images.

Surgicoanatomical aspect in vascular variations of the V3 segment of vertebral artery as a risk factor for C1 instrumentation.

OBJECT: Awareness of vascular anomalies in V3 segment of vertebral artery (VA) is crucial to avoid iatrogenic injuries during surgical procedure. This study aimed to analyze the incidence of V3 segment vascular variations and demonstrate the importance of deciding the surgical strategy for C1 screw placement. METHODS: Prevalence of vascular variations and morphometric measurements of the VA in the region of the craniocervical junction in 200 cases based on three-dimensional computed tomographic angiography (3D-CTA) scans were studied. RESULTS: The VA has a variable course through C2 before it passes above its groove on the posterior arch of C1. Following the vascular variations of V3 segments of VA were persistent including first intersegmental artery (FIA), fenestration (FEN) of the VA, high-riding (HRVA and the posterior inferior cerebellar artery (PICA) branch originating from the C1/2 part of VA. HRVA was observed in 10.1% of patients, FIA in 1.8%, FEN in 1.3%, and PICA in 1.3%. One hundred and twenty-three (24.1%) patients were identified to have HRVA, 6% present on both sides. CONCLUSION: The VA with FIA and FEN were rare in this study as many as a 10% the VA present over the starting point for C1 lateral screw. With respect to the vascular anatomy of V3 and more frequent left-sided VA dominancy, standard screw insertion should be started from the right side. Routine preoperative 3D-CTA evaluation is mandatory to prevent the VA injury when C1-C2 instrumentation is planned.

Patient-Specific Three-Dimensional Model for a Safe Surgical Pathway in Sacral Chondrosarcoma.

Sacral tumors are amongst the most challenging procedures to treat because of the complex anatomy. This study determined whether patient-specific models change preoperative planning decisions made in preparation for en bloc resection of complex sacral mass surgical procedures. Imaging showed a big encapsulated mass at the S2-3 level involving the neural foramina and obscuring the nerve roots. High-resolution images were acquired and utilized to generate a patient-specific 3D tumor model. The visual and tactile inspection of 3D models allowed the best anatomical understanding, with faster and clearer comprehension of the surgical anatomy. The 3D sacral model was for observation of previously unapparent anatomical details; with this new technology, surgeon can observe their planned surgical intervention, explore the patient-specific anatomy and extension of the tumor, and sharpen their procedure choices. Moreover, multiple planes showed how far the angles on the plane would extend for osteotomy of the sacrum. Another result was identifying correct guides and safe venture landmarks. The study helped to establish safe osteotomy line wherever the nerve roots were retained and enabled osteotomy by preserving bilaterally the S1 and S2 nerve roots for wide excision of wide excision of primary sacral tumor to get adequate bowel and bladder functions. Finally, it helped to determine whether or not the remaining bone in the sacrum is sufficient for spinopelvic stability and needed fixation. It was decided spinopelvic fixation was not necessary for this case. Surgical intervention of sacral tumors varies depending on the tumor, its size, extension, and location. Surgery can have profound risks including unnecessary nerve root resection spinopelvic instability and suboptimal oncological resection. 3D models help to transfer complex anatomical information to clinicians and provide guidance in the preoperative planning stage, for intraoperative navigation and for surgical training purposes.

Multidisciplinary Assessment of Planning and Resection of Complex Bone Tumor Using Patient-Specific 3D Model.

Oncological interventions in thoracic cavity have some important problems such as choice of correct operative approaches depending on the tumor, size, extension, and location. In sarcoma surgery, wide resection should be aimed for the curative surgery. Purpose of this study was to evaluate pre-operative planning of patient-specific thoracic cavity model made by multidisciplinary surgeon team for complex tumor mass for oncological procedures. Patient's scans showed a large mass encroaching on the mediastinum and heart, with erosion of the adjacent ribs and vertebral column. Individual model of this case with thoracic tumor was reconstructed from the DICOM file of the CT data. Surgical team including six interdisciplinary surgeons explained their surgical experience of the use of 3D life-size individual model for guiding surgical treatment. Before patients consented to surgery, each surgeon explained the surgical procedure and perioperative risks to her. A questionnaire was applied to 10 surgical residents to evaluate the 3D model's perception. 3D model scans were useful in determining the site of the lesion, the exact size, extension, attachment to the surrounding structures such as lung, aorta, vertebral column, or vascular involvement, the number of involved ribs, whether the diaphragm was involved also in which order surgeons in the team enter the surgery. 3D model's perception was detected statistical significance as < 0.05. Viewing thoracic cavity with tumor model was more efficient than CT imaging. This case was surgically difficult as it included vital structures such as the mediastinal vessels, aorta, ribs, sternum, and vertebral bodies. A difficult pathology for which 3D model has already been explored to assist anatomic visualization was mediastinal osteosarcoma of the chest wall, diaphragm, and the vertebral column. The study helped to establish safe surgical line wherever the healthy tissue was retained and enabled osteotomy of the affected spinal corpus vertically with posterior-anterior direction by preserving the spinal cord and the spinal nerves above and distal the tumor. 3D tumor model helps to transfer complex anatomical information to surgeons, provide guidance in the pre-operative planning stage, for intra-operative navigation and for surgical collaboration purposes. Total radical excision of the bone tumor and reconstructions of remaining structures using life-size model was the key for successful treatment and better outcomes. The recent explosion in popularity of 3D printing is a testament to the promise of this technology and its profound utility in orthopedic oncological surgery.

3D Brain Imaging in Vascular Segmentation of Cerebral Venous Sinuses.

The three-dimensional (3D) visualization of dural venous sinuses (DVS) networks is desired by surgical trainers to create a clear mental picture of the neuroanatomical orientation of the complex cerebral anatomy. Our purpose is to document those identified during routine 3D venography created through 3D models using two-dimensional axial images for teaching and learning neuroanatomy. Anatomical data were segmented and extracted from imaging of the DVS of healthy people. The digital data of the extracted anatomical surfaces was then edited and smoothed, resulting in a set of digital 3D models of the superior sagittal, inferior sagittal, transverse, and sigmoid, rectus sinuses, and internal jugular veins. A combination of 3D printing technology and casting processes led to the creation of realistic neuroanatomical models that include high-fidelity reproductions of the neuroanatomical features of DVS. The life-size DVS training models were provided good detail and representation of the spatial distances. Geometrical details between the neighboring of DVS could be easily manipulated and explored from different angles. A graspable, patient-specific, 3D-printed model of DVS geometry could provide an improved understanding of the complex brain anatomy. These models have various benefits such as the ability to adjust properties, to convert two-dimension images of the patient into three-dimension images, to have different color options, and to be economical. Neuroanatomy experts can model such as the reliability and validity of the designed models, enhance patient satisfaction with improved clinical examination, and demonstrate clinical interventions by simulation; thus, they teach neuroanatomy training with effective teaching styles.

Physical attractiveness: analysis of buttocks patterns for planning body contouring treatment.

BACKGROUND: As buttocks region is one of the most characteristic features of the ideal female body figure, the popularity of gluteal region contouring is on the rise. Perception of body form is influenced by its shape and size. Interventions to modify the form of this region are often difficult due to influence. The aim of this study is to investigate the attractiveness of various buttock shapes with the aid of a dedicated software. METHODS: Standard personal photographs of the lower body were obtained from 200 healthy volunteers. Linear analyses were made and anatomical perception was calculated according to reference points. RESULTS: Compared to males, all measurements concerning buttock dimensions were a significantly greater in females. Proportional assessments revealed that in females, the most attractive buttock waist-to-hip ratio was 0.75 from the posterior view. This ratio was 0.85 in males. From the lateral view, the most attractive buttocks have a waist-to-hip ratio of 0.70 in females. Positioning of the lateral prominence at the inferior gluteal fold was rated by 25% of the respondents as the most attractive in males from the posterior view. From the lateral view, the most prominent portion positioned at the midpoint (a 50:50 vertical ratio) was considered the most attractive for females. CONCLUSIONS: These results suggest that utilizing digitalized reference values for a given body region may be an invaluable tool for determination of the correct fat volume, thus individualization of body contouring procedures. With the help of certain software, this research has shown that it is possible to measure the parameters of buttock, which may in turn be used to offer the best solution for any individual in quest for an improved buttocks form. New ideal waist-to-hip ratios of 0.7 update the previous standards.

Creation of 3-Dimensional Life Size: Patient-Specific C1 Fracture Models for Screw Fixation.

BACKGROUND: Transarticular screw fixation has fatal complications such as vertebral artery (VA), carotid artery, and spinal cord injuries. The landmarks for deciding the entry point for C1 lateral mass screws were clarified by using life-size 3-dimensional (3D) patient-specific spine models. METHODS: This study included a total of 10 patients with C1 fractures. Dual-energy computed tomography (CT) scan data from C1 pre- and postscrewing were modified into 3D patient-specific life-size cervical spine models. The detailed information, such as bony and vascular elements, of 13 separate parameters of C1 was used as an intraoperative reference. RESULTS: 3D patient-specific models were created preoperatively with the fracture and postoperatively with the screwed vertebrae. After CT scans of the models were measured, the life-size patient-specific models were proven to be individualized. 3D models assisted in determining the fracture locations, pedicle sizes, and positions of the VA. The range of the measurements for ideal point of entry reveals the need for patient-specific intervention was required. CONCLUSIONS: 3D models were used in surgical planning maximizing the possibility of ideal screw position and providing individualized information concerning cervical spinal anatomy. The individualized 3D printing screw insertion template was user-friendly, of moderate cost, and it enabled a radiation-free cervical screw insertion.

The Ponticulus Posticus as Risk Factor for Screw Insertion into the First Cervical Lateral Mass.

BACKGROUND: Awareness of the osseous anomaly of ponticulus posticus (PP) is crucial in avoiding vertebral artery (VA) injuries during C1 instrumentation. The aim of this study was to investigate PP and its relationship with the VA with three-dimensional computed tomography angiography. METHODS: PP and the VA were investigated as intraoperative landmarks. The intersection of the VA to the posterior arch of C1 and the medial line and the posterior arch and VA curve around lateral masses were measured as intraoperative references. RESULTS: PP was identified in 14.3% of samples. The anomaly was more common in women and on the right side. Of cases, 48.2% had PP bilaterally. In PP cases, the VA had variable courses through C2 before it passed under its bony bridges on the posterior arch of C1. Mean distances were found at the intersection of the VA to the posterior arch of C1 and the medial line to be larger and the posterior arch of C1 and the VA curve around lateral masses to be narrower than normal cases. Dual computed tomography scan data from C1 with PP were used to create three-dimensional patient-specific life-sized cervical spine models. Models revealed how the bone bridge affected the VA. The feasibility (>4 mm) of a safe lateral mass screw fixation was not influenced by PP anomalies. CONCLUSIONS: The presence of the PP loop can limit space available for placement of the screw through the bony elements of C1. Standard screw techniques are contraindicated owing to the unacceptable high risk of VA injury.