First experiences with the Airo mobile intraoperative CT scanner in acetabular surgery-An analysis of 10 cases

Image Quality Comparison of Three 3D Mobile X-Ray Imaging Guidance Devices Used in Spine Surgery: A Phantom Study

An image-quality CT phantom was scanned with three different 3D X-ray imaging guidance devices in the operating theatre: O-Arm, Loop-X, and Airo TruCT. Default acquisition and reconstruction parameters for lumbar spine procedures were used on each device. The tube current was set to a dose level of around 27 mGy. A task-based image quality assessment was performed by calculating the noise power spectrum (NPS) and task transfer function (TTF). A detectability index (d') was calculated for three simulated bone lesions. The noise magnitude of the O-Arm was higher than the Airo TruCT, and the Loop-X had higher noise than the Airo TruCT. The highest average NPS frequency was for the O-Arm images, and the lowest was for the Loop-X. The TTFs at 50% values were similar for the Airo TruCT and Loop-X devices. Compared to Airo TruCT, the TTF at 50% value increased with the O-Arm by 53.12% and 41.20% for the Teflon and Delrin inserts, respectively. Compared to Airo TruCT, the d' value was lower with Loop-X by -26.73%, -27.02%, and -23.95% for lytic lesions, sclerotic lesions, and high-density bone, respectively. Each 3D-imaging spine surgery guidance device has its own strengths and weaknesses in terms of image quality. Cone-beam CT systems apparently offer the best compromise between noise and spatial resolution for spine surgery.

Head Face and Neck Surgeon Deployment in the New French Role 2: The Damage Control Resuscitation and Surgical Team

INTRODUCTION

High-intensity conflict is back after decades of asymmetric warfare. With the increase in the incidence of head, face, and neck (HFN) injuries, the French Medical Military Service has decided to deploy HFN surgeons in the new French Role 2: the Damage Control, Resuscitation, and Surgical Team (DCRST). This study aims to provide an overview of HFN French surgeons from their initial training, including the surgical skills required, to their deployment on the DCRST.

MATERIALS AND METHODS

The DCRST is a tactical mobile medico-surgical structure with several configurations depending on the battlefield, mission, and flux of casualties. It represents the new French paradigm for the management of combat casualties, including HFN injuries.

RESULTS

The HFN's military surgeon training starts during residency with rotation in the different subspecialties. The HFN surgeon follows a training course called "The French Course for Deployment Surgery" that provides sufficient background to manage polytrauma, including HFN facilities on modern warfare. We have reviewed the main surgical procedures required for an HFN military surgeon.

CONCLUSION

The systematic deployment of HFN surgeons in Role 2 is a specificity of the French army as well as the HFN surgeon's training.Currently, the feedback from an asymmetric conflict is encouraging. However, it will have to innovate to adapt to modern warfare.

Intraoperative Computed Tomography in Orthopaedic Trauma Surgery

BACKGROUND

When using mobile 3D C-arms, impairments in image quality occur due to artefacts caused by metal implants as well as to the limited field of view. To avoid these restrictions, special computed tomography devices were designed, in order to improve image quality and to meet requirements for intraoperative usage.

OBJECTIVES

To analyse practicability and benefits of a mobile intraoperative CT device (Airo, Brainlab, Munich, Germany) on the basis of several parameters that were obtained during a 40-month period.

MATERIALS AND METHODS

All procedures that were performed with usage of intraoperative CT between January 2017 and April 2020 were analysed with respect to anatomical region, count of scans, duration of scans, consequences drawn from the scans and use of navigation.

RESULTS

354 CT-scans were performed in 171 patients (mean 2.07 [1 - 6] scans per procedure). 47.81% of the procedures were spinal, 52.19% affected the pelvis. 83% of the procedures were navigated. In 22% of patients, improvement in implant placement or reduction was achieved; in most patients (55%), a guidewire for pedicle screws was corrected. The mean scan duration was 10.33 s (3.54 - 21.72).

CONCLUSIONS

Use of intraoperative CT was reliable and helpful. Integration in OR standards requires more effort than mobile 3D C-arms. Image quality was outstanding for intraoperative conditions and allowed proper assessment of implant placement and reduction in all cases. Due to the high financial outlay of the system and the good image quality of 3D C-arms in the extremities, we assume that this procedure can be applied in intraoperative CT in traumatological cases in spinal and pelvic surgery in high-level trauma centres.

Technical evaluation of the cone-beam computed tomography imaging performance of a novel, mobile, gantry-based X-ray system for brachytherapy

Purpose

A novel, mobile cone‐beam computed tomography (CBCT) system for image‐guided adaptive brachytherapy was recently deployed at our hospital as worldwide first site. Prior to the device's clinical operation, a profound characterization of its imaging performance was conducted. This was essential to optimize both the imaging workflow and image quality for achieving the best possible clinical outcomes. We present the results of our investigations.

Methods

The novel CBCT‐system features a ring gantry with 121 cm clearance as well as a 43.2 × 43.2 cm² flat‐panel detector, and is controlled via a tablet‐personal computer (PC). For evaluating its imaging performance, the geometric reproducibility as well as imaging fidelity, computed tomography (CT)‐number accuracy, uniformity, contrast‐noise‐ratio (CNR), noise characteristics, and spatial resolution as fundamental image quality parameters were assessed. As dose metric the weighted cone‐beam dose index (CBDI_w) was measured. Image quality was evaluated using standard quality assurance (QA) as well as anthropomorphic upper torso and breast phantoms. Both in‐house and manufacturer protocols for abdomen, pelvis, and breast imaging were examined.

Results

Using the in‐house protocols, the QA phantom scans showed altogether a high image quality, with high CT‐number accuracy (R² > 0.97) and uniformity (<12 Hounsfield Unit (HU) cupping), reasonable noise and imaging fidelity, and good CNR at bone–tissue transitions of up to 28:1. Spatial resolution was strongly limited by geometric instabilities of the device. The breast phantom scans fulfilled clinical requirements, whereas the abdomen and pelvis scans showed severe artifacts, particularly at air/bone–tissue transitions.

Conclusion

With the novel CBCT‐system, achieving a high image quality appears possible in principle. However, adaptations of the standard protocols, performance enhancements in image reconstruction referring to artifact reductions, as well as the extinction of geometric instabilities are imperative.

First experiences with intraoperative CT in navigated sacroiliac (SI) instrumentation: An analysis of 25 cases and comparison with conventional intraoperative 2D and 3D imaging

BACKGROUND

Intraoperative imaging is regularly used for intraoperative reduction control and evaluation of the implant position in trauma surgery. 2D imaging is limited, especially in complex anatomical regions such as the pelvis. The introduction of mobile 3D C-arms (CBCT: cone-beam computed tomography) has significantly improved intraoperative assessment. Nevertheless, there are still limitations regarding the field of view and metal artifacts. The purpose of this study was to evaluate the potential of intraoperative computed tomography (iCT) in surgical treatment of sacroiliac (SI) injuries.

METHODS

Twenty-five cases with injuries of the posterior pelvic ring involving the SI region that were surgically treated with navigated SI screws using the mobile iCT Airo (Brainlab, Munich, Germany) were analysed. Subsequently, the data were compared with historical control groups (CBCT with and without navigation; 2D fluoroscopy only).

RESULTS

The average score for subjective image quality achieved using the Likert scale is significantly higher for the iCT (4.48 ± 0.65) than for the CBCT (3.04 ± 0.69) with p = 0.00. The average duration of surgery using iCT was 189.32 ± 88.64 min, which was not significantly different from the control groups (p = 0.14 - 0.70). The average fluoroscopy time using iCT was 81.96 ± 97.34 s, which was significantly shorter than in all of the control groups (p = 0.00 - 0.03). The rate for postoperatively detected complications after using iCT was 0% (n = 0). Compared with the 2D-only control group (25%; n = 1), there is a significant difference (p = 0.01). The remaining two control groups showed no significant differences (p = 0.09 - 0.19).

CONCLUSIONS

The iCT provides excellent image quality that allows reliable assessment of fracture reduction and implant placement even in complex anatomical regions. The radiation exposure for the medical staff is reduced by decreasing the fluoroscopy time without significantly prolonging the surgical time. Overall, the possibility of intraoperative correction improves clinical outcome and patient treatment in the long term.

Does the use of intraoperative CT scan improve outcomes in Orthopaedic surgery? A systematic review and meta-analysis of 871 cases

BACKGROUND

Intraoperative imaging is frequently made use of in Orthopaedic surgery. Historically, conventional 2-dimensional fluoroscopy has been extensively used for this purpose. However, 2D imaging falls short when it is required to visualise complex anatomical regions such as pelvis, spine, foot and ankle etc. Intraoperative 3D imaging was introduced to counter these limitations, and is increasingly being employed in various sub-specialities of Orthopaedic Surgery.

OBJECTIVES

This review aims to outline the clinical and radiological outcomes of surgeries done under the guidance of intraoperative 3D imaging and compare them to those done under conventional 2D fluoroscopy.

METHODS

Three electronic databases (PubMed, Embase and Scopus) were searched for relevant studies that directly compared intraoperative 3D imaging with conventional fluoroscopy. Case series on intraoperative 3D imaging were also included for qualitative synthesis. The outcomes evaluated included accuracy of implant placement, mean surgical duration and rate of revision surgery due to faulty implants.

RESULTS

A total of 31 studies from sub-specialities of spine surgery, pelvi-acetabular surgery, foot and ankle surgery and trauma surgery, having data on a total of 658 patients were analysed. The study groups which had access to intraoperative 3D imaging was found to have significantly increased accuracy of implant positioning (Odds Ratio 0.35 [0.20, 0.62], p = 0.0002) without statistically significant difference in mean surgical time (p = 0.57). Analysis of the studies that included clinical follow up showed that the use of intraoperative 3D imaging led to a significant decrease in the need for revision surgeries due to faulty implant placement.

CONCLUSION

There is sufficient evidence that the application of intraoperative 3D imaging leads to precise implant positioning and improves the radiological outcome. Further research in the form of prospective studies with long term follow up is required to determine whether this superior radiological outcome translates to better clinical results in the long run.

The Damage Control Resuscitation and Surgical Team: The New French Paradigm for Management of Combat Casualties

INTRODUCTION

The aim of this work was to introduce the new French forward resuscitation and surgical unit. It's also to discuss the choices and waivers granted to fit the tactical context of modern conflicts and the current epidemiology of combat casualties.

MATERIALS AND METHODS

A multidisciplinary task force of 11 people proceeded to the conception and the creation of a new military resuscitation and surgical unit. The preliminary work included a scoping review of the combat casualties' epidemiology in modern conflicts and an analysis of the recent French medical-surgical treatment facilities lessons learned. In April 2019, a technical-operational evaluation was conducted to confirm all the technical, ergonomic, and organizational choices made during the design phase.

RESULTS

The multidisciplinary task force resulted in the creation of the Damage Control Resuscitation and Surgical Team (DCRST). The DCRST focused on the resuscitation strategy, including transfusion of blood products, and the life-saving surgical procedures to be performed as close as possible to the point of injury. It was designed for the resuscitation of two patients: the life-saving surgery of two patients and the very short-term intensive care (<12 hours) of four patients at the same time. The DCRST provided sufficient autonomy to provide take care of four T1 and four T2 or T3 casualties per day for 48 hours. It was armed with 23 soldiers. The technical equipment represented 5,300 kg and 27 m3. All the technical medical equipment could be stored in two 20-foot containers.

CONCLUSION

The DCRST represents a new paradigm in medical support of French military operations. It offers the advantage of two combat casualties' surgical management at the same time, as close as possible to the combat zone. It responds to a 2-fold epidemiological and logistical challenge.

Finding NEEMO: towards organizing smart digital solutions in orthopaedic trauma surgery

There are many digital solutions which assist the orthopaedic trauma surgeon. This already broad field is rapidly expanding, making a complete overview of the existing solutions difficult.The AO Foundation has established a task force to address the need for an overview of digital solutions in the field of orthopaedic trauma surgery.Areas of new technology which will help the surgeon gain a greater understanding of these possible solutions are reviewed.We propose a categorization of the current needs in orthopaedic trauma surgery matched with available or potential digital solutions, and provide a narrative overview of this broad topic, including the needs, solutions and basic rules to ensure adequate use in orthopaedic trauma surgery. We seek to make this field more accessible, allowing for technological solutions to be clearly matched to trauma surgeons' needs. Cite this article: EFORT Open Rev 2020;5:408-420. DOI: 10.1302/2058-5241.5.200021.