Use Of Intraoperative Imaging Research Articles

Surgical treatment of nasal fractures may benefit from intraoperative 3D imaging

This retrospective study aimed to assess the effects of the use of intraoperative three-dimensional (3D) imaging on outcomes in surgical treatment of nasal fractures. Furthermore, we investigated whether the use of intraoperative imaging improves outcomes and decreases the frequency of corrective surgeries compared to published literature. This retrospective descriptive study included patients who underwent operative treatment for nasal fractures with the use of intraoperative 3D imaging between January 2015 and January 2020at a University Hospital. The primary outcome measure was patient satisfaction, which was assessed through patient charts about subjective esthetic problems and nasal obstruction. The secondary outcome measures were the number of intraoperative images and necessity of intra- and postoperative revisions. All the outcomes were evaluated using regression analysis. Of the 172 patients, secondary rhinoplasty and intraoperative revision were performed in 10 (6 %) and 93 (54 %) patients, respectively. Postoperatively, 19 (11 %) and 12 (7 %) patients complained of subjective esthetic problems and nasal obstruction, respectively. The intraoperative revision rate in patients undergoing surgical treatment of nasal fractures with intraoperative 3D imaging was >50 %. However, the incidence of postoperative secondary revision, nasal obstruction, and subjective esthetic problems was lower than that reported in the literature not having an intraoperative imaging. Our findings suggest that prompt quality control of the operative result enables immediate correction and prevents postoperative revision.

Identifying Predictors of Initial Surgical Failure during Minimally Invasive Endoscopic Intracerebral Hemorrhage Evacuation.

Background and Purpose: Intracerebral hemorrhage (ICH) is a common and severe disease with high rates of morbidity and mortality; however, minimally invasive surgical (MIS) hematoma evacuation represents a promising avenue for treatment. In February of 2019, the MISTIE III study found that stereotactic thrombolysis with catheter drainage did not benefit patients with supratentorial spontaneous ICH but that a clinical benefit may be present when no more than 15 mL of hematoma remains at the end of treatment. Intraoperative CT (iCT) imaging has the ability to assess whether or not this surgical goal has been met in real time, allowing for operations to add additional CT-informed 'evacuation periods' (EPs) to achieve the surgical goal. Here, we report on the frequency and predictors of initial surgical failure on at least one iCT requiring additional EPs in a large cohort of patients undergoing endoscopic minimally invasive ICH evacuation with the SCUBA technique. Methods: All patients who underwent minimally invasive endoscopic evacuation of supratentorial spontaneous ICH in a major health system between December 2015 and October 2018 were included in this study. Patient demographics, clinical and radiographic features, procedural details, and outcomes were analyzed retrospectively from a prospectively collected database. Procedures were characterized as initially successful when the first iCT demonstrated that surgical success had been achieved and initially unsuccessful when the surgical goal was not achieved, and additional EPs were performed. The surgical goal was prospectively identified in December of 2015 as leaving no more than 20% of the preoperative hematoma volume at the end of the procedure. Descriptive statistics and regression analyses were performed to identify predictors of initial failure and secondary rescue. Results: Patients (100) underwent minimally invasive endoscopic ICH evacuation in the angiography suite during the study time period. In 14 cases, the surgical goal was not met on the first iCT and multiple Eps were performed; in 10 cases the surgical goal was not met, and no additional EPs were performed. In 14 cases, the surgical goal was never achieved. When additional EPs were performed, a rescue rate of 71.4% (10/14) was seen, bringing the total percentage of cases meeting the surgical goal to 86% across the entire cohort. Cases in which the surgical goal was not achieved were significantly associated with older patients (68 years vs. 60 years; p = 0.0197) and higher rates of intraventricular hemorrhage (34.2% vs. 70.8%; p = 0.0021). Cases in which the surgical goal was rescued from initial failure had similar levels of IVH, suggesting that these additional complexities can be overcome with the use of additional iCT-informed EPs. Conclusions: Initial and ultimate surgical failure occurs in a small percentage of patients undergoing minimally invasive endoscopic ICH evacuation. The use of intraoperative imaging provides an opportunity to evaluate whether or not the surgical goal has been achieved, and to continue the procedure if the surgeon feels that more evacuation is achievable. Now that level-one evidence exists to target a surgical evacuation goal during minimally invasive ICH evacuation, intraoperative imaging, such as iCT, plays an important role in aiding the surgical team to achieve the surgical goal.

Optimizing vestibular implant electrode positioning using fluoroscopy and intraoperative CT imaging

Purpose Vestibular implant electrode positioning close to the afferent nerve fibers is considered to be key for effective and selective electrical stimulation. However, accurate positioning of vestibular implant electrodes inside the semicircular canal ampullae is challenging due to the inability to visualize the target during the surgical procedure. This study investigates the accuracy of a new surgical protocol with real-time fluoroscopy and intraoperative CT imaging, which facilitates electrode positioning during vestibular implant surgery.Methods Single-center case-controlled cohort study with a historic control group at a tertiary referral center. Patients were implanted with a vestibulocochlear implant, using a combination of intraoperative fluoroscopy and cone beam CT imaging. The control group consisted of five patients who were previously implanted with the former implant prototype, without the use of intraoperative imaging. Electrode positioning was analyzed postoperatively with a high-resolution CT scan using 3D slicer software. The result was defined as accurate if the electrode position was within 1.5 mm of the center of the ampulla.ResultsWith the new imaging protocol, all electrodes could be positioned within a 1.5 mm range of the center of the ampulla. The accuracy was significantly higher in the study group with intraoperative imaging (21/21 electrodes) compared to the control group without intraoperative imaging (10/15 electrodes), (p = 0.008).Conclusion The combined use of intraoperative fluoroscopy and CT imaging during vestibular implantation can improve the accuracy of electrode positioning. This might lead to better vestibular implant performance.

COMPARATIVE STUDY OF REVISION HIP ARTHROPLASTY AFTER SHORT STEM VERSUS AFTER CONVENTIONAL STEM

AbstractObjectiveShort-stem total hip arthroplasty (THA) aims to preserve the proximal bone stock for future revisions, so that the first revision should resemble a primary intervention rather than a revision. This study aimed to compare the clinical and radiological outcomes in revision THA after failed short stem versus after failed conventional stem THA.MethodsThis study included forty-five patients with revision THA divided into three groups (15 each); group A: revision after short stem, group B: revision after conventional cementless stem and group C revision after conventional cemented stem. The studied groups were compared regarding 31 variables including demographic data, details of the primary and revision procedures, postoperative radiological subsidence, hospital stay, time for full weight bearing (FWB), preoperative and postoperative clinical scores.ResultsEarly stem subsidence (40%) was the main indication of revision in group A compared to peri-prosthetic femoral fractures (PFFs) (73.3%) and aseptic loosening (53.3%) in group B and C respectively (P=0.021). The mean time to revision was significantly shorter in group A (15 months) compared to 95.33 and 189.40 months in group B and C respectively. (P=0.005). Sixty % (9 patients) in group A were revised in the first year. The mean operative time, blood loss, postoperative blood transfusion and hospital stay were significantly lower in group A compared to group B and C (P<0.001, <0.001, 0.002 and 0.001 respectively). Revisions in group A were performed using either short stems (13.3%) or conventional stems (86.7%) whilst 80% of patients needed long stems and 20% of patients needed conventional stems in group B and C (P<0.001). The mean postoperative Harris Hip Score (HHS) at the latest follow up was 87.07, 87.53 and 85.47 in group A, B and C respectively. All PFFS had excellent results according to Beal's and Tower's criteria; all fractures healed and the implants were stable.ConclusionThe most common cause of failure of short stems is early stem subsidence. Short stem THA has specific indications and patient selection is very crucial. Preoperative templating for short stems and a detailed analysis of the individual patient anatomy in anteroposterior and lateral views are mandatory to predict the correct implant size more accurately. The use of intraoperative imaging can verify the sizing, implant position, and sufficient contact with the lateral cortex. Revision of short stem THA resembled the primary THA. If a standard implant can be used in a surgical revision instead of a longer revision stem, this can be considered as an advantage for the hip arthroplasty treatment concept. However, this only applies if the longevity of the first treatment with a short stem is comparable with that of a standard stem.Declaration of Interest(b) declare that there is no conflict of interest that could be perceived as prejudicing the impartiality of the research reported:I declare that there is no conflict of interest that could be perceived as prejudicing the impartiality of the research project.

The impact of operative approach and intraoperative imaging on leg length discrepancy and acetabular component angle in total hip arthroplasty: a retrospective cohort study.

Operative approach in total hip arthroplasty (THA) has long been a topic of debate with each approach having unique benefits and disadvantages. One purported benefit of an anterior approach to THA is that it allows for intraoperative positioning using fluoroscopy rather than manual positioning. Proper positioning allows for improved outcomes including leg length discrepancy and acetabular component angle. This study aims to examine if operative approach and use of imaging in intraoperative positioning impact LLD and cup angle post-operatively. A total of 300 hips were enrolled in the study with 100 hips per approach (anterior with fluoroscopy, lateral, and posterior). Retrospective chart review was conducted to assess patient demographics and radiographic analysis used to determine LLD and acetabular cup angle. Of the three groups, those receiving anterior approach THAs were on average older than those in the posterior group. Analysis comparing the LLD and acetabular angle across the three groups showed no statistically significant difference in LLD (p=0.091); this was also reflected when comparing hips that received fluoroscopy with those that did not (p=0.91). For acetabular angle, while no difference existed when comparing hips that received imaging versus those that did not, statistically significant differences were observed when comparing the three intraoperative approaches (p<0.0001). Neither intraoperative approach nor the use of intraoperative imaging in THA has a statistically significant effect on LLD post-operatively. However, approach did impact the acetabular cup angle across all three distinct approaches.

Role of Intraoperative Imaging in Improving Closed Reduction of Zygomatic Arch Fractures: A Systematic Review and Meta-analysis

The use of intraoperative imaging (IOI) to improve the reduction adequacy of zygomatic arch (ZMA) fractures has been reported, but few systematic reviews have examined this topic. The aim of this review was to investigate and compare the value of IOI with conventional methods without IOI (N-IOI) for the closed reduction of ZMA fractures. Electronic retrieval of MEDLINE, Embase, Cochrane Library, Web of Science, Scopus, and citation search until December 2, 2022, was used to identify controlled clinical trials that employed IOI for improving adequacy in closed reduction of ZMA fractures. The predictor variable was the use of IOI-yes/no (IOI vs N-IOI). The covariates included imaging technique (ultrasound, C-arm, and cone beam computed tomography) and ZMA fracture type (M-shape fracture, mechanistic force in 1 direction; variable fracture, mechanistic force in 2 directions). The primary outcome variables were the reduction adequacy of ZMA fractures (the remaining cortical step and dislocation angle) compared with the ideal mirrored position. Weighted or mean differences, risk ratios, and corresponding 95% confidence intervals were calculated, where P >.05 and I2＜50% fixed effect model was adopted, and a vice versa random effect model was adopted. A total of 1250 studies were identified, of which 6 studies with 259 participants were included. The meta-analysis results indicated that compared with N-IOI, IOI yielded fewer cortical steps (-1.76 [-2.42, 1.10], P ＜.00001, fixed model) and dislocation angles (-5.60 [-8.08, 3.12], P＜.00001, fixed model) in patients with variable ZMA fractures, while no significant difference was detected in the M-shape ZMA fracture (-0.72, [-2.93, 1.48], P=.52; -1.48, [-3.51, 0.55], P=.15). Although there was no significant difference in postoperative correction (0.35, [0.06, 2.01] P=.24, fixed model), all secondary revision cases occurred in the N-IOI group. Descriptive analysis showed that IOI yielded better symmetry and appearance satisfaction. IOI improved the adequacy of the procedure and led to a better postoperative appearance, especially for patients with variable ZMA fractures. Furthermore, the use of IOI avoided the risk of secondary surgery. In future studies, researchers should standardize the scale and outcomes to facilitate the intuitive evaluation of reduction adequacy.

Outcome of Operative Treatment of Intraarticular Fractures of Calcaneum

Introduction: Calcaneum is the most commonly fractured tarsal bone and account for approximately 2% of all fractures. Controversy continues regarding the management of calcaneal fractures. Earlier conservative management was preferred, and surgical management considered inappropriate for these fractures. This trend is gradually changing with better understanding of disabling nature of injuries in combination with improved implant and routine use of intra-operative imaging. However, still clinical evidence supporting operative treatment is limited and complications are frequently documented. Thus, this study aims to investigate the functional and radiological outcome of intra-articular calcaneal fracture treated with calcaneal plate. Methods: This study is a prospective analytic study. The study was conducted in the Department of Orthopaedics, B.P Koirala Institute of Health Sciences, a tertiary care hospital in Eastern Nepal, over a period of twelve months from September 2018 to August 2019. Patients presenting with calcaneal fracture were screened for eligibility by clinico-radiological evaluation. Twenty-eight cases that presented to BPKIHS and gave consent and fulfilled the inclusion criteria were selected. Two cases were lost to follow up. So, 26 cases of were included in the final analysis. Results: Average age of the patients was 32 years (22-54) years. There was male predominance with M:F ratio of 10:3. Most common mode of injury was fall from height (24) followed by RTA (2). Sanders’ type 2B was the most common fracture pattern. There was significant improvement in Bohler angle (25.1°), calcaneal height (4.3cm) and width(3.9cm). Average AOFAS score at final follow up was 81.4 (81% had score &gt; 75). Average VAS score at final follow up was 7.9±1.3. Conclusion: Open reduction and internal fixation with plate is associated with good clinical and functional outcome in Sander type II and III fractures. With good surgical techniques, improved implant and proper use of fluoroscopy, proper restoration of Bohler angle, calcaneal height and width can be achieved. Key Words: Calcaneum, Intraarticular, Plate fixation.

FUNCTIONAL AND RADIOLOGICAL ANALYSIS OF SURGICALLY MANAGED DISPLACED INTRA-ARTICULAR CALCANEUM FRACTURE

One of the most common foot fractures is fracture of calcaneum. It is usually caused by high energy trauma, with 75% being intraarticular. Advances in imaging, implants, AO principles of internal xation and the routine use of intraoperative imaging have made internal xation a recommended procedure in recent past. The study included 38 patients of int Material and methods: ra-articular calcaneal fractures treated operatively with ORIF with PO using the modied Kocher's approach. The patients were assessed radiologically and for functional outcome as per AOFAS (American Orthopedic Foot and Ankle Score) score. 43 fract Results: ures in 38 patients were included in our study with mean age of 38.58 years. 56% had good and 44% had excellent results with nal AOFAS score. All radiological parameters like Böhlers angle, Gissane's angle and calcaneal width and height showed improvement following surgery, with later three having statistical signicance. There was no inuence of complications following surgery over nal AOFAS score. Surgical Conclusion: management of calcaneal fracture require thorough understanding of anatomy and various radiological parameters. Careful patient selection, preoperative planning, appropriate timing for surgery, proper approach and accurate anatomic reduction gives a good functional outcome. Sander's classication helps in surgical planning as well as prognostication.

The case for intra-operative X-ray in cochlear implantation: Four illustrative cases and literature review

Objectives: To demonstrate the utility of routine intraoperative plain film imaging in optimizing outcomes in cochlear implantation. Introduction: Evolving surgical techniques, programming, and electrode arrays have all improved performance outcomes in cochlear implantation. Yet despite decreasing complication rates, electrode misplacement remains a common occurrence. Utilization of intraoperative confirmational tools (radiologic, electrophysiologic) remains unstandardized despite the acknowledged importance of proper electrode positioning. The purpose of this article is to illustrate the use and benefits of intraoperative X-ray (IOXR) in four cases, particularly in cases of normal electrophysiologic testing. Methods: Four cases performed by an experienced CI surgeon are discussed where electrode malposition was only detected through X-ray. Literature review was performed on the use of intraoperative imaging, focusing on plain film radiography. Results: Case 1–3 describe examples of resistance-free electrode insertion in patients with normal pre-operative imaging. Intraoperative impedances and neural response telemetry (NRT) were normal. However, IOXR ultimately revealed tip fold-over prompting array repositioning. Case 4 describes an elective replacement of a soft-failing device. Resistance was encountered during array insertion, with IOXR demonstrating incomplete insertion compared with prior imaging. Positioning was revised to achieve pre-revision insertion depth, demonstrating the utility of prior IOXR in revision cases. Literature review of IOXR is discussed. Conclusion: Appropriate placement of the electrode is paramount to successful CI outcomes. These cases illustrate IOXR as a safe, effective method to ensure optimal placement even in cases of normal electrophysiologic testing, supporting its routine use even by the most seasoned surgeons.

First Clinical Experience with a Novel 3D C-Arm-Based System for Navigated Percutaneous Thoracolumbar Pedicle Screw Placement

Background and Objectives: Navigated pedicle screw placement is becoming increasingly popular, as it has been shown to reduce the rate of screw misplacement. We present our intraoperative workflow and initial experience in terms of safety, efficiency, and clinical feasibility with a novel system for a 3D C-arm cone beam computed-tomography-based navigation of thoracolumbar pedicle screws. Materials and Methods: The first 20 consecutive cases of C-arm cone beam computed-tomography-based percutaneous pedicle screw placement using a novel navigation system were included in this study. Procedural data including screw placement time and patient radiation dose were prospectively collected. Final pedicle screw accuracy was assessed using the Gertzbein–Robbins grading system. Results: In total, 156 screws were placed. The screw accuracy was 94.9%. All the pedicle breaches occurred on the lateral pedicle wall, and none caused clinical complications. On average, a time of 2:42 min was required to place a screw. The mean intraoperative patient radiation exposure was 7.46 mSv. Conclusions: In summary, the investigated combination of C-arm CBCT-based navigation proved to be easy to implement and highly reliable. It facilitates the accurate and efficient percutaneous placement of pedicle screws in the thoracolumbar spine. The careful use of intraoperative imaging maintains the intraoperative radiation exposure to the patient at a moderate level.

MRI-based and robot-assisted stereotactic biopsy with intraoperative CT imaging.

As a pioneer center in the field of stereotaxy, Sainte-Anne school has always advocated the use of intraoperative imaging for stereotactic procedures to optimize both safety and accuracy. With the advent of intraoperative mobile CT unit, the robot-assisted stereotactic biopsy procedure has been recently updated. Herein, we aim at describing our new surgical procedure that combines robotic assistance (NeuroMate, Renishaw) and intraoperative cone beam CT imaging (O-Arm, Medtronic). Intraoperative imaging with the O-Arm was efficiently incorporated into the workflow. This new equipment leads to optimizing operative time and an easier realization of intraoperative imaging.

Direct anterior approach hip arthroplasty: How to reduce complications - A 10-years single center experience and literature review.

BACKGROUNDThe direct anterior approach for total hip arthroplasty (DAA-THA) is increasing in popularity due to some advantages such as less surgical trauma, minimal dissection of soft tissues, shorter rehabilitation times, faster return to daily activities, lower incidence of dislocation. On the other hand, the literature reports a high rate of intraoperative complications, with many different rates and complication types in the published papers. AIMTo analyze our complications comparing results with the literature; to report measures that we have taken to reduce complications rate.METHODSAll DAA-THA patients with one year minimum follow up who were operated at a single high-volume centre, between January 2010 and December 2019 were included in this retrospective study. All surgeries were performed using cementless short anatomical or straight stems and press fit cups. Patients’ follow-up was performed, at 6 wk, 3 mo, then annually post-surgery with clinical and radiological evaluation. Primary outcomes were stem revision for aseptic loosening and all-cause stem revision. Second outcome was intra-operative and post-operative complications identification.RESULTSA total of 394 patients underwent DDA-THA from January 2010 and December 2019, for a total of 412 hips; twelve patients lost to follow-up and one patient who died from causes not related to surgery were excluded from the study. The average age at the time of surgery was 61 years (range from 28 to 78 years). Mean follow-up time was 64.8 mo (range 12-120 mo). Seven stems were revised. One cortical perforation, one trochanteric and lateral cortical wall intraoperative fracture, one diaphyseal fracture, three clinically symptomatic early subsidence and one late aseptic loosening. We also observed 3 periprosthetic fractures B1 according to the Vancouver Classification. Other minor complications not requiring stem revision were 5 un-displaced fractures of the calcar region treated with preventive cerclage, one early infection, one case of late posterior dislocation, 18 case of asymptomatic stem subsidence, 6 cases of lateral cutaneous femoral nerve dysesthesia.CONCLUSIONDAA is associated to good outcomes and lower incidence of dislocation. Complication rate can be reduced by mindful patient selection, thorough preoperative planning, sufficient learning curve and use of intraoperative imaging.

Subpial en bloc resection improves extent of resection in infiltrating gliomas – A propensity matched comparative cohort analysis

BackgroundSurgery remains the mainstay of glioma therapy and extent of resection is an important prognostic factor. Optimization of surgical outcomes is essential and to this end the technique of resection can potentially play an important role. Based on patterns of glioma growth and extrapolating from other solid cancer surgical principles, a subpial dissection combined with an en-bloc resection (SPER) technique appears to have advantages MethodsWe performed a propensity matched analysis comparing gliomas that were resected using SPER versus a standard piecemeal debulking technique at our centre. Potentially confounding factors (including eloquent location, use of intraoperative imaging, surgeon experience) were adjusted for in the matching of the two cohorts. Outcomes included postoperative morbidity and blinded radiological review documented postoperative ischemia (on diffusion weighted MR imaging - DWI) as well as extent of resection. ResultsIn 57 gliomas (23 SPER and 34 standard), the gross total resection (GTR) rates were significantly higher with SPER (91 vs 65%). Postoperative DWI revealed significant ischemia in almost 50% of cases in either group, though many did not have postoperative deficits. Arterial ischemia was higher in the standard surgery group and this was associated with a significantly higher risk (seven times) of resulting in prolonged neurological deficits. ConclusionsSPER is a useful technique which increases the GTR rates in gliomas undergoing resection. It is associated with lower incidence of arterial ischemia in the postoperative period and this can result in improved long term functional outcomes.

Intraoperative Imaging in Total Hip Arthroplasty Is Cost-Effective Regardless of Surgical Approach

BackgroundComponent positioning in total hip arthroplasty (THA) may be improved with utilization of intraoperative imaging. The purpose of this study is to determine if intraoperative imaging during THA is cost-effective. MethodsA break-even analysis was used as a model for cost-effectiveness, which incorporates cost of imaging (including direct charges and the additional time required for imaging), rate of revision surgery, and cost of revision surgery, yielding a final revision rate that needs to be achieved with use of intraoperative imaging in order for its use to be cost-effective. Absolute risk reduction (ARR) is determined by the difference between the initial revision rate and final revision rate. ResultsAt an anticipated institutional cost of $120 and requiring 4 additional minutes, intraoperative fluoroscopy would be cost-effective if the baseline rate of revision due to component mispositioning (0.62%) is reduced to 0.46%. Intraoperative flat plate radiographs ($127) are cost-effective at an ARR of 0.16%. Cost-effectiveness is achieved with lower ARR in the setting of lower imaging costs ($15, ARR 0.02%), and higher ARR with higher imaging costs ($225, ARR 0.29%). ARR for cost-effectiveness is independent of baseline revision rate, but varies with the cost of revision procedures. ConclusionAt current revision rates for component malpositioning, only 1 revision among 400 THAs needs to be prevented for the utilization of fluoroscopy (or 1 in 385 THAs with flat plate imaging), to achieve cost-effectiveness.

Outcome of Operative Treatment of Intraarticular Fractures of Calcaneum

Backgroud: Calcaneum is the most commonly fractured tarsal bone. Approximately 75% are intra-articular fractures. Controversy continues regarding the management of calcaneal fractures. Earlier conservative management was preferred and surgical management considered inappropriate for these fractures. This trend is gradually changing with better understanding of disabling nature of injuries in combination with improved implant and routine use of intra-operative imaging. Closed treatment with cast invariably leads to long-term complications. However, still clinical evidence supporting operative treatment is limited and complications are frequently documented. Objectives: To evaluate the functional outcome of intraarticular fractures of calcaneum in terms of American Orthopaedic Foot and Ankle Society (AOFAS) score and Visual Analogue Scale (VAS) score. Methods: This study was a retrospective analytic study. The study was conducted in the Department of Orthopaedics, B.P. Koirala Institute of Health Sciences, Nepal. Data collection and analysis of patients operated from July 2017 to June 2019 was done. Twenty six cases that fulfilled inclusion criteria were analysed. Results: Average age of the patients was 32 years. Sanders type 2B was the most common fracture pattern. There was significant improvement in Bohler angle (25.1°), calcaneal height (4.3cm) and width (3.9cm). Average AOFAS score and VAS score at final follow up were 81.4 and 7.9 respectively. Conclusion: Open reduction and internal fixation with plate is associated with good clinical and functional outcome in Sander type II and III fractures. With good surgical techniques, improved implant and proper use of fluoroscopy, proper restoration of Bohler angle, calcaneal height and width can be achieved.

Use of Intraoperative Imaging to Preserve C1-C2 Mobility in Complex Atlas-Hangman Fractures.

Combination fractures of the C1-C2 complex especially atlas and hangman are relatively uncommon and management usually compromises C1-C2 mobility. To evaluate the treatment of combined C1- hangman's fracture with and without intraoperative O- arm based navigation system, and its outcome in terms of preserving C1-C2 mobility. This was a case series of patients with combined C1 and hangman's fracture, managed at a tertiary care hospital during February 2009 to December 2016. Neurological function assessed with American Spine Injury Association (ASIA) impairment scale. Radiological fusion of the operated segment assessed with computed tomographic scan, criteria used for successful fusion included formation of callus across the fracture. Preservation of rotational motion between C1 and C2 was assessed by cervical flexion rotation (CFR) test. We included 10 patients (male/female: 9/1; mean 47.7 ± 17.5 years) in our study. Operative intervention was performed in 9 patients. We used intraoperative computed tomogram (CT) scan with navigation in 5 patients. The mean follow-up period was 28.7 months (range 6 to 70 months). Neurological recovery occurred in all 4 patients with preoperative neurological deficits. Radiological fusion occurred in all cases. Rotation at C1-2 was preserved in all 5 cases operated under O-arm guidance and in one patient with type 1 fracture who was managed conservatively. The goals in treating these complex fractures are to achieve early maximum stability and preserving maximum range of motion. These are often competing phenomena, which can be achieved by using intra operative CT scan and navigation system.

Calcar-guided short-stem total hip arthroplasty: Will it be the future standard? Review and perspectives.

Short stems in total hip arthroplasty (THA) are becoming increasingly popular. In Germany, already 10.4% of all primary THAs are performed using a cementless short stem. The concept of modern, calcar-guided, short stems aims for an individualized reconstruction of the hip anatomy by following the calcar of the femoral neck, a bone- and soft-tissue-sparing implantation technique, and physiological loading. The stem design uses either metaphyseal fixation alone or additional diaphyseal anchoring, depending on the stem alignment and indication. These individualized anchorage types increase the potential indications for the safe use of a short stem. The design features may account for potential advantages of current short stem implants compared with earlier short-stem designs, particularly in cases of reduced bone quality or osteonecrosis of the femoral head and femoral neck fractures. The implantation technique, however, requires distinct knowledge regarding the characteristics of varus and valgus positioning, with the potential for clinical consequences. A learning curve for surgeons new to this technique must be taken into account. Cortical contact with the distal lateral cortex appears to be crucial to provide sufficient primary stability, and the use of intraoperative imaging to identify “undersizing” is highly recommended. Current results of several national registries indicate that calcar-guided short stems are among the most successful implants in terms of mid-term survivorship. However, long-term data remain scarce. This review introduces the characteristics of calcar-guided short-stem THA and summarizes the current evidence.

Evaluation and Verification of Fast Computational Simulations of Stent-Graft Deployment in Endovascular Aneurysmal Repair.

Fenestrated Endovascular Aortic Repair, also known as FEVAR, is a minimally invasive procedure that allows surgeons to repair the aorta while still preserving blood flow to kidneys and other critical organs. Given the high complexity of FEVAR, there is a pressing need to develop numerical tools that can assist practitioners at the preoperative planning stage and during the intervention. The aim of the present study is to introduce and to assess an assistance solution named Fast Method for Virtual Stent-graft Deployment for computer assisted FEVAR. This solution, which relies on virtual reality, is based on a single intraoperative X-ray image. It is a hybrid method that includes the use of intraoperative images and a simplified mechanical model based on corotational beam elements. The method was verified on a phantom and validated on three clinical cases, including a case with fenestrations. More specifically, we quantified the errors induced by the different simplifications of the mechanical model, related to fabric simulation and aortic wall mechanical properties. Overall, all errors for both stent and fenestration positioning were less than 5 mm, making this method compatible with clinical expectations. More specifically, the errors related to fenestration positioning were less than 3 mm. Although requiring further validation with a higher number of test cases, our method could achieve an accuracy compatible with clinical specifications within limited calculation time, which is promising for future implementation in a clinical context.

Design, delivery, and evaluation of seminars and hands-on courses worldwide on intraoperative imaging in orthopedic trauma

IntroductionAlthough intraoperative imaging is important for assessing the quality of several steps during fracture fixation, most trainees and surgeons have received little formal education on this topic and report they learn "on the job" and "through practice". A planning committee of orthopedic trauma surgeons was established to design a curriculum using "backward planning" to identify patient problems, identify gaps in surgeons' knowledge and skills, and define competencies as a framework for education in order to optimize patient care. Materials and methodsThe committee defined 8 competencies related to intraoperative imaging, with detailed learning objectives for each one (e.g. select the imaging modality, set up the operating room). An interactive, case-based half-day seminar to deliver these objectives for 2-D and 3-D intraoperative imaging during the fixation of common fractures was designed. The seminar was delivered in several locations worldwide over a 6-year period and evaluation and assessment data were gathered online. A full-day procedures course was added and delivered 6 times to address the skills component of competencies. Results17 seminars and 6 courses were delivered and attended by an average of 26 and 17 participants respectively (ranges 13–42 and 13–20). Pre-event gap analysis and assessment question scores confirmed needs and motivation to learn in all events. 97% of the 442 seminar participants and 98% of the 100 course participants would recommend the events to colleagues. An average of 88% and 90% respectively learned something new and plan to use it in their practice (range 63%-100%). Commitment to change (CTC) statements showed intended practice improvements related to all competencies. DiscussionThe large percentages of high impact ratings for all events suggest the content met the needs of many participants. Post-event reduction in gap scores and an increase in the desired level of ability for most competencies suggests the content addressed many gaps. ConclusionsCase-based, interactive seminars and courses addressing knowledge, skills, and attitudes to optimize the use of intraoperative imaging during the fixation of common fractures help address unmet educational needs for trainees and complements existing formal training.

Intraoperative MRI for Brain Tumors.

The use of intraoperative imaging has been a critical tool in the neurosurgeon's armamentarium and is of particular benefit during tumor surgery. This article summarizes the history of its development, implementation, clinical experience and future directions. We reviewed the literature focusing on the development and clinical experience with intraoperative MRI. Utilizing the authors' personal experience as well as evidence from the literature, we present an overview of the utility of MRI during neurosurgery. In the 1990s, the first description of using a low field MRI in the operating room was published describing the additional benefit provided by improved resolution of MRI as compared to ultrasound. Since then, implementation has varied in magnetic field strength and in configuration from floor mounted to ceiling mounted units as well as those that are accessible to the operating room for use during surgery and via an outpatient entrance to use for diagnostic imaging. The experience shows utility of this technique for increasing extent of resection for low and high grade tumors as well as preventing injury to important structures while incorporating techniques such as intraoperative monitoring. This article reviews the history of intraoperative MRI and presents a review of the literature revealing the successful implementation of this technology and benefits noted for the patient and the surgeon.