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

Task-based image quality assessment of an intraoperative CBCT for spine surgery compared with conventional CT

PURPOSE

To analyze the image quality of a novel, state-of-the art platform for CBCT image-guided spine surgery, focusing particularly on the dose-effectiveness compared with conventional CT (the gold standard for postoperative assessment).

METHODS

The ClarifEye platform (Philips Healthcare) with integrated augmented-reality surgical navigation, has been compared with a GE Revolution CT (GE Healthcare). The 3D spatial resolution (TTF) and noise (NPS) were evaluated considering relevant feature contrasts (200-900 HU) and background noise for differently sized patients (200-300 mm water-equivalent diameter). These measures were used to determine the noise equivalent quanta (NEQ) and observer model detectability.

RESULTS

The CBCT system exhibited a linear response with 50% TTF at 5.7 cycles/cm (10% TTF at 9.2 cycles/cm), and the axial noise power peaking at about 3.6 cycles/cm (average frequency of 4.1 cycles/cm). The noise magnitude and texture differed markedly compared to iteratively reconstructed CT images (GE ASiR-V). The CBCT system had 26% lower detectability for a high-frequency task (related to edge detection) compared with CT images reconstructed using the Bone kernel combined with ASiR-V 50%. Likewise, it had 18% lower detectability for low- and mid-frequency tasks compared with CT images reconstructed using the Standard kernel. This difference translates to 50%-80% higher CBCT imaging doses required to match the CT image quality.

CONCLUSIONS

The ClarifEye platform demonstrates intraoperative CBCT-imaging capabilities that under certain circumstances are comparable with conventional CT. However, due to limited dose-effectiveness, a trade-off between timeliness and radiation exposure must be considered if end-of-procedure CBCT is to replace postoperative CT.

Diagnostic applications and benefits of weightbearing CT in the foot and ankle: A systematic review of clinical studies

BACKGROUND

Foot and ankle weightbearing CT (WBCT) imaging has emerged over the past decade. However, a systematic review of diagnostic applications has not been conducted so far.

METHOD

A systematic literature search was performed according to the Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA) guidelines after Prospective Register of Systematic Reviews (PROSPERO) registration. Studies analyzing diagnostic applications of WBCT were included. Main exclusion criteria were: cadaveric specimens and simulated WBCT. The Methodological Index for Non-Randomized Studies (MINORS) was used for quality assessment.

RESULTS

A total of 78 studies were eligible for review. Diagnostic applications were identified in following anatomical area's: ankle (n = 14); hindfoot (n = 41); midfoot (n = 4); forefoot (n = 19). Diagnostic applications that could not be used on weightbearing radiographs (WBRX) were reported in 56/78 studies. The mean MINORS was 9.8/24 (range: 8-12).

CONCLUSION

Diagnostic applications of WBCT were most frequent in the hindfoot, but other areas are on the rise. Post-processing of images was the main benefit compared to WBRX based on a moderate quality of the identified studies.

Is Intraoperative CT Navigation feasible for excision of osteoid osteoma in the appendicular skeleton? - Retrospective analysis of 58 cases

Background

The use of intraoperative CT navigation to manage osteoid osteoma is not common. We report our experience managing osteoid osteoma in the appendicular skeleton using an intraoperative AIRO CT navigation system.

Materials & methods

Between May 2013 and December 2022, 59 patients underwent Navigation-assisted excision of osteoid osteoma in the appendicular skeleton. Our primary study outcome was to assess for recurrence of the tumour with recurrence of symptoms. For our secondary outcomes, we evaluated the complications associated with the procedure and evaluated the histological slides of all patients to see for the presence of nidus.

Results

Of the 58 patients available for review, no patient had a lesion recurrence, and all were symptom-free at an average follow-up of 45.6 months (6-100). Two patients (3.5%) had a superficial infection managed conservatively, and 43 patients (74.1%) had the presence of nidus in curetted samples. No patient developed a pathological fracture after the procedure.

Conclusion

Using intraoperative CT navigation to manage osteoid osteoma in the appendicular skeleton is safe, minimally invasive, and effective in completely removing the nidus with a negligible complication rate. The absence of nidus on histology should not be a concern to clinicians once thorough burring and verification of excision of nidus has been confirmed intra-operatively.

Study design

Retrospective Case Series.

Level of evidence

Level IV.

The use of hybrid operating rooms in neurosurgery, advantages, disadvantages, and future perspectives: a systematic review

BACKGROUND

Hybrid operating rooms (hybrid-ORs) combine the functionalities of a conventional surgical theater with the advanced imaging technologies of a radiological suite. Hybrid-ORs are usually equipped with CBCT devices providing both 2D and 3D imaging capability that can be used for both interventional radiology and image guided surgical applications. Across all fields of surgery, the use of hybrid-ORs is gaining in traction, and neurosurgery is no exception. We hence aimed to comprehensively review the use of hybrid-ORs, the associated advantages, and disadvantages specific to the field of neurosurgery.

MATERIALS AND METHODS

Electronic databases were searched for all studies on hybrid-ORs from inception to May 2022. Findings of matching studies were pooled to strengthen the current body of evidence.

RESULTS

Seventy-four studies were included in this review. Hybrid-ORs were mainly used in endovascular surgery (n = 41) and spine surgery (n = 33). Navigation systems were the most common additional technology employed along with the CBCT systems in the hybrid-ORs. Reported advantages of hybrid-ORs included immediate assessment of outcomes, reduced surgical revision rate, and the ability to perform combined open and endovascular procedures, among others. Concerns about increased radiation exposure and procedural time were some of the limitations mentioned.

CONCLUSION

In the field of neurosurgery, the use of hybrid-ORs for different applications is increasing. Hybrid-ORs provide preprocedure, intraprocedure, and end-of-procedure imaging capabilities, thereby increasing surgical precision, and reducing the need for postoperative imaging and correction surgeries. Despite these advantages, radiation exposure to patient and staff is an important concern.

Projected Lifetime Cancer Risk Associated With Intraoperative Computed Tomography for Lumbar Spine Surgery

STUDY DESIGN

Retrospective cross-sectional study.

OBJECTIVE

(1) To determine the incremental increase in intraoperative ionizing radiation conferred by computed tomography (CT) as compared with conventional radiography; and (2) to model different lifetime cancer risks contextualized by the intersection between age, sex, and intraoperative imaging modality.

SUMMARY OF BACKGROUND DATA

Emerging technologies in spine surgery, like navigation, automation, and augmented reality, commonly utilize intraoperative CT. Although much has been written about the benefits of such imaging modalities, the inherent risk profile of increasing intraoperative CT has not been well evaluated.

MATERIALS AND METHODS

Effective doses of intraoperative ionizing radiation were extracted from 610 adult patients who underwent single-level instrumented fusion for lumbar degenerative or isthmic spondylolisthesis from January 2015 through January 2022. Patients were divided into those who received intraoperative CT (n=138) and those who underwent conventional intraoperative radiography (n=472). Generalized linear modeling was utilized with intraoperative CT use as a primary predictor and patient demographics, disease characteristics, and preference-sensitive intraoperative considerations ( e.g. surgical approach and surgical invasiveness) as covariates. The adjusted risk difference in radiation dose calculated from our regression analysis was used to prognosticate the associated cancer risk across age and sex strata.

RESULTS

(1) After adjusting for covariates, intraoperative CT was associated with 7.6 mSv (interquartile range: 6.8-8.4 mSv; P <0.001) more radiation than conventional radiography. (2) For the median patient in our population (a 62-year-old female), intraoperative CT use increased lifetime cancer risk by 2.3 incidents (interquartile range: 2.1-2.6) per 10,000. Similar projections for other age and sex strata were also appreciated.

CONCLUSIONS

Intraoperative CT use significantly increases cancer risk compared with conventional intraoperative radiography for patients undergoing lumbar spinal fusions. As emerging technologies in spine surgery continue to proliferate and leverage intraoperative CT for cross-sectional imaging data, strategies must be developed by surgeons, institutions, and medical technology companies to mitigate long-term cancer risks.

Intraoperative revision rates due to three-dimensional imaging in orthopedic trauma surgery: results of a case series of 4721 patients

PURPOSE

Intraoperative 3D imaging has become a valued tool in assessing the quality of reduction and implant placement in orthopedic trauma surgery. In our institution, 3D imaging is used routinely since 2001. To evaluate the intraoperative findings and consequences of this technique, intraoperative revision rates in cases with 3D imaging were analyzed.

METHODS

All operative procedures carried out with intraoperative 3D imaging between August 2001 and December 2016 were included. The scans were assessed intraoperatively and documented thereafter. In case of malreduction or misplaced implants, an immediate revision was performed. The number of scans per case as well as the findings and consequences drawn regarding the anatomical region were analyzed.

RESULTS

4721 cases with 7201 3D scans were included in this study. The most common anatomical regions were the ankle (22.3%), the calcaneus (14.8%) and the tibial head (9.5%). In 19.1% of all cases, an intraoperative revision was performed. The highest revision rates were found with 36.0% in calcaneal fractures, 24.8% in fractures of the tibial plateau, 22.3% in injuries of the ankle. In 52.0% of revisions, the reduction was improved regarding intra-articular steps or joint congruency. In 30.5% an implant was corrected.

CONCLUSION

Intraoperative revision due to results of 3D imaging was performed in almost one-fifth of cases. This illustrates the improved possibilities to detect malreduction and implant misplacements intraoperatively and thus the abilities to improve surgical outcome.

LEVEL OF EVIDENCE

III.

Suture button versus syndesmotic screw in ankle fractures - evaluation with 3D imaging-based measurements

BACKGROUND

Inadequate reduction of syndesmotic injuries can result in disabling clinical outcomes. The aim of the study was to compare syndesmosis congruity after fixation by syndesmotic screws (SYS) or a suture button system (SBS) using three-dimensional (3D) computed imaging techniques.

METHODS

In a retrospective single-center study, patients with unilateral stabilization of an ankle fracture with a syndesmotic injury and post-operative bilateral CT scans were analyzed using a recently established 3D method. The side-to-side differences were compared for tibio-fibular clear space (∆CS), translation angle (∆α), and vertical offset (∆z) among patients stabilized with syndesmotic screws or suture button system. Syndesmotic malreduction was defined for ∆CS > 2 mm and for |∆α| > 5°. ∆CS and ∆α were correlated with two-dimensional (2D) measurements.

RESULTS

Eighteen patients stabilized with a syndesmosis screw and 29 stabilized with a suture button system were analyzed. After stabilization, both groups revealed mild diastasis (SYS: mean ∆CS 0.3 mm, SD 1.1 mm vs SBS: mean ∆CS 0.2 mm, SD 1.2 mm, p = 0.710). In addition, both stabilization methods showed slight dorsalization of the fibula (SYS: mean ∆α 0.5°, SD 4.6° vs SBS: mean ∆α 2.1°, SD 3.7°, p = 0.192). Also, restoration of the fibula-to-tibia length ratio also did not differ between the two groups (SYS: mean Δz of 0.5 mm, SD 2.4 mm vs SBS: mean Δz of 0 mm, SD 1.2 mm; p = 0.477). Malreduction according to high ∆α was most common (26% of cases), with equal distribution between the groups (p = 0.234). ∆CS and ∆α showed good correlation with 2D measurements (ρ = 0.567; ρ = 0.671).

CONCLUSION

This in vivo analysis of post-operative 3D models showed no differences in immediate post-operative alignment after syndesmotic screws or suture button system. Special attention should be paid to syndesmotic malreduction in the sagittal orientation of the fibula in relation to the tibia in radiological control of the syndesmotic congruity as well as intra-operatively.