How useful is intraoperative cone beam computed tomography in maxillofacial surgery? An overview of the current literature

Intraoperative imaging is increasingly used by surgeons and has become an integral part of many surgical procedures. This study was performed to provide an overview of the current literature on the intraoperative use of cone beam computed tomography (CBCT) imaging in maxillofacial surgery. A bibliographic search of PubMed was conducted in March 2020, without time limitation, using “intraoperative imaging” AND “maxillofacial surgery” AND “cone beam computed tomography” as key words. Ninety-one articles were found; after complete reading, 16 articles met the eligibility criteria and were analysed. The results showed that the majority of the indications were related to maxillofacial trauma, particularly zygomaticomaxillary complex fractures. Final verification with intraoperative CBCT before wound closure was the most common use of this device. However, innovative uses of intraoperative CBCT are expanding, such as CBCT coupling with mirror computational planning, and even the combined use of initial intraoperative CBCT acquisition with navigation. Immediate, fast, and easy evaluation of bone repositioning to avoid the need for further surgical revision is the main advantage of this technique. Imaging quality is comparable to that of multi-slice computed tomography, but with lower radiation exposure. Nevertheless, CBCT is still not widely available in maxillofacial centres, probably because of its cost, and perhaps because not everyone is aware of its advantages and versatility, which are reported in this review.     

Pneumatic tourniquets in maxillofacial surgery: do we need to change practice? A national study

The use of pneumatic tourniquets during the harvest of free flaps is an established practice in oral and maxillofacial surgery. Their use can be associated with severe but preventable complications, for which operating surgeons are ultimately responsible. The aim of this study was to find any pitfalls concerning the safe use of tourniquets by maxillofacial surgeons. An electronic questionnaire based on the Association of Perioperative Registered Nurses (AORN) guidelines was distributed to maxillofacial surgeons nationally. A total of 37 questionnaires were completed and analysed. The mean (range) score for the knowledge-based questions for all respondents was 72.8% (47.3%–94.7%). The number of clinicians who answered correctly on topics relating to cuff position, reperfusion time and contraindications for the use of tourniquets were 15, 10 and 6, respectively. A total of 35 clinicians had had no formal training on the application of a tourniquet. Our study shows that knowledge about their use by maxillofacial surgeons is poor, and it highlights the importance of formal education during basic and higher surgical training.     

Do we need practitioner training schemes in orthodontics?

Orthodontic treatment appears to be in ever-increasing demand, but the number of specialists is insufficient to meet the current need. This article considers the role of the extended practitioner training scheme in the present climate of uncertainty surrounding orthodontics in the general dental services in the UK, particularly for the general dental practitioner.     

Assessing symmetry of zygomatic bone through three-dimensional segmentation on computed tomography scan and “mirroring” procedure: A contribution for reconstructive maxillofacial surgery

Purpose

Surgical reconstruction of zygomatic bones in cases of traumatic injuries is a frequent event: assessment of symmetry is mandatory for a correct restoration of zygomatic shape, but the literature is discordant about its quantification. The purpose of this study is to show a novel method for assessing symmetry of zygomatic bone through mirroring of 3D models segmented on CT-scan.

Simulation-based training in maxillofacial surgery: are we going to be left behind?

Simulation is an important way both to optimise a trainee’s learning time and reduce morbidity and operating time for patients. We have reviewed the current use of simulation in training for maxillofacial surgery, and provide an overview of areas of practice where it may be useful. A web-based survey of trainees’ opinions of it was made in February 2018, and disseminated using the Junior and Fellows in Training group mailing lists. We also reviewed popular current simulation courses that are available. A total of 45 of the 57 trainees who replied agreed that simulation-based training would be beneficial in maxillofacial surgery, particularly with regard to maxillofacial surgical emergencies. A total of 54 of the 57 also agreed that simulation-based training would be a useful adjunct to their clinical training. However, most of the simulation-based courses available were priced beyond the budgets available to UK-based trainees for study, although funding changed in April 2018. While other surgical disciplines have adopted simulated clinical teaching and its benefits, maxillofacial surgery has limited the use of all types of formal simulation. Surgical simulation training is increasingly being used to complement the traditional surgical apprenticeship in other specialties, and ours needs to consider ways in which we can use it, given that trainees within the specialty think that it would be useful. Other specialties have shown that there is good transfer of skills from simulation to the actual clinical operating environment, and this increases satisfaction, decreases morbidity, and reduces the time required for intraoperative teaching.     

Are three-dimensional airway evaluations obtained through computed and cone-beam computed tomography scans predictable from lateral cephalograms? A systematic review of evidence

Objective:To systematically review the literature correlating upper airway parameters between lateral cephalograms (LC) and cone-beam computed tomography (CBCT) or computed tomography (CT) scans to determine the utility of using LC to predict three-dimensional airway parameters.Materials and Methods:Both electronic and manual searches of the included studies were performed by two reviewers, and the quality of the studies that met selection criteria were assessed.Results:A total of 11 studies from the literature met the selection criteria. Assessed outcome variables showed correlation r < .7 between the LC and CT scans. The correlation between the LC and CBCT ranged from weak to strong with −.78 ≤ r and r ≤ .93 reported in the nasopharyngeal segment. In the oropharyngeal segment, a weak to strong correlation was reported with a range of −37 ≤ r and r ≤ .83 between the CBCT and LC. All associations in the hypopharyngeal segment showed a weak correlation. Four of studies were of weak quality, five were of moderate quality, and two were rated to be of strong quality.Conclusion:No strong correlations were reported between the LC and CT scans. However, the LC-derived adenoid-nasopharyngeal ratio and the linear measurement (posterior nasal spine, PNS, to posterior pharyngeal wall) had a strong correlation with upright nasopharyngeal area and volume in the CBCTs. The area measurement in conventional LC can be also used as an initial screening tool to predict the upright three-dimensional oropharyngeal volumetric data. The variability of the hypopharyngeal segment cannot be predicted by LCs. However, more well-designed studies are needed to determine the clinical utility of using LC to predict airway size.     

Can magnetic resonance imaging replace single photon computed tomography and computed tomography in detecting bony invasion in patients with oral squamous cell carcinoma?

AIM: To determine whether MRI can replace SPECT and CT in detecting bone invasion in patients with oral SCC. MATERIALS AND METHODS: A retrospective and independent review of the MRI, SPECT, and when available CT, images of 23 patients with oral malignancy who had formal bone resection was undertaken. Our gold standard was histopathology. RESULTS: Bone involvement was seen in 19/23 resections. Sensitivity of MRI was 100% [95% CI 1.0-1.0] and specificity was 75% [95% CI 0.326-1.174]. Sensitivity of SPECT was 100% [95% CI 1.0-1.0] and specificity was 50% [95% CI 0.01-0.99]. CONCLUSIONS: MRI is accurate in predicting bone involvement. The addition of SPECT and CT to routine MRI staging protocols seems no longer indicated. CT may be useful in some selected cases to determine maxillary involvement due to the thinner cortex of the maxilla.     

The prevalence of pneumatized articular eminence in the temporal bone. Do we need a high resolution computed tomography-based novel risk classification for eminectomy?

Introduction

Besides mastoid air filled cells, pneumatizations (PN) occasionally occur in the articular eminence (AE) of the temporomandibular joint (TMJ). These findings represent no pathological character but may increase the risk of perforating the AE during eminectomy with potential harming the skull base. Various classifications catagorize the degree of temporal PN without focussing solely on the AE. Panoramic radiograph (PR) and computed tomographie (CT) are both described as suitable for diagnosing PNs. Are the common ways of imaging capable for precise diagnosis and do we need a risk pattern for eminectomy?