Use of Intraoperative Computed Tomography in Craniomaxillofacial Trauma Surgery

Intraoperative Computed Tomography in the Surgical Treatment of Zygomatic Complex Fracture: A Retrospective Cohort Study

This study aimed to assess the effectiveness of intraoperative computed tomography (ICT) in managing zygomatic complex (ZMC) fractures surgically. A total of 143 patients (84 men, 59 women; average age 37.13 y) undergoing surgical treatment for ZMC fractures participated in this retrospective cohort study, with 72 in the ICT group and 71 in the control group. There were no notable differences in gender, age, time from injury to surgery, and surgical duration between the two groups. The ICT group exhibited significantly fewer surgical approaches than the control group (1.39±0.519 vs. 2.07±0.617, P<0.001). Fixation points in the ICT group (1-point: 42, 2-point: 14, 3-point: 16) significantly differed from the control group (1-point: 15, 2-point: 17, 3-point: 39), P<0.001. Symmetry of reduction was assessed through immediate postoperative images, and stability was compared between immediate postoperative images and those taken at least 3 months later. Both assessments revealed no significant differences between the 2 groups. This study indicates that ICT facilitates prompt evaluation of ZMC reduction, minimizing the necessity for incisions and internal fixation, while achieving comparable reduction efficacy and long-term stability to conventional approaches.

Off-Label Use of an External Hand Fixator for Craniomaxillofacial Fractures-An Anatomical Feasibility Study

BACKGROUND

The lack of resources limits the treatment of craniomaxillofacial fractures (CMF) in low-income countries (LIC). Therefore, Barton bandages and/or interdental wiring are considered in these regions. Fracture reduction is maintained by permanent occlusion for 6 weeks, which often leads to limited compliance and dissatisfying results. The aim of this cadaver-based study is to evaluate the feasibility of the use of an external face fixator (EFF) for the treatment of CMF, its biomechanical values and to define the optimal pin insertion points and angles.

MATERIALS AND METHODS

An AO hand fixator was used. CMF of types Le Fort 1-3 with split fractures of the hard palate were treated with EFF on 13 anatomical specimens. Fractures were created using a chisel, and pins were placed in specific anatomical regions. The maximal pull-out force [N] of pins was analysed by a tensile force gauge, and Fmax of the mandibular pins was evaluated. Computer tomography scans were performed on the healthy, fractured and EFF-treated skulls.

RESULTS

The pull-out forces for the single pins were mandibular pins (n = 15, median 488.0 N), supraorbital pins (n = 15, median 455.0 N), zygomatic pins (n = 14, median 269.1 N), medial hard palate pins (n = 12, median 208.4 N) and lateral hard palate pins (n = 8, median 49.6 N).

CONCLUSIONS

The results indicate that the operation technique is feasible, and the stability of the EFF is sufficient for maintaining the reduction. The required pins can safely be inserted into the described areas with good reduction results. Using EFF offers a feasible alternative to the non-surgical treatment of CMF in LIC.

The Application of Cone Beam Computed Tomography (CBCT) on the Diagnosis and Management of Maxillofacial Trauma

The assessment and management of facial trauma in an acute setting is one of the core services provided by oral and maxillofacial units in the United Kingdom. Imaging is a pre-requisite for appropriate diagnosis and treatment planning, with a combination of plain radiographs and medical-grade CT being the mainstay. However, the emergence of cone beam CT in recent years has led to its wider applications, including facial trauma assessment. It can offer multi-planar reformats and three-dimensional reconstruction at a much lower radiation dose and financial cost than conventional CT. The purpose of this review is to appraise its potential indications in all anatomical areas of maxillofacial trauma and provide our experience at a level 1 trauma centre.

Intraoperative computed tomography for orbital reconstruction: a systematic review

Orbital reconstruction is a common procedure with inherent challenges and important consequences. Intraoperative use of computed tomography (CT) is an emerging application that facilitates accurate intraoperative evaluation to improve clinical outcomes. This review aims to investigate the intraoperative and postoperative outcomes of intraoperative CT use in orbital reconstruction. PubMed and Scopus databases were systematically searched. Inclusion criteria were: clinical studies investigating intraoperative CT use in orbital reconstruction. Exclusion criteria were: duplicates; non-English publications; non-full-text publications; studies with insufficient data. Of the 1022 articles identified, seven eligible articles representing 256 cases were included. The mean age was 39 years. Most cases were male (69.9%). With regards to intraoperative outcomes, the mean revision rate was 34.1%, with plate repositioning being the most common type (51.1%). Intraoperative time was variably reported. With regards to postoperative outcomes, there were no revisions, and only one case that had a complication (transient exophthalmos). Mean volumetric difference between the repaired and contralateral orbits was reported in two studies. The findings of this review present an updated evidence-based summary of the intraoperative and postoperative outcomes of intraoperative CT use in orbital reconstruction. Robust longitudinal comparisons of clinical outcomes between intraoperative and non-intraoperative CT cases are required.

Applications of Preoperative and Intraoperative Technologies for Complex Primary and Secondary Facial Trauma Reconstruction

This article provides a review of the current technologies available in the preoperative and intraoperative management of complex and secondary maxillofacial trauma reconstruction. These patients present a unique challenge for which the advancement of imaging technologies, patient-specific modeling and implants, and intraoperative imaging and navigation can play an important role to improve their post-treatment outcomes.

Predictors of Intraoperative Difficulty and Postoperative Examination Abnormalities in 164 Orbital Operations

BACKGROUND

Although orbital fractures are common, prediction of outcomes in orbital surgery can be quite challenging.

PURPOSE

We aim to identify predictors of intraoperative difficulty, operating time, and postoperative examination abnormalities in subjects undergoing post-traumatic orbital reconstructions.

STUDY DESIGN, SETTING, AND SAMPLE

This is a retrospective cohort study of all consecutive orbital operations performed at a private, Level 1 trauma center in Portland, Oregon, USA over an 82-month period. All subjects that underwent exploration of the internal orbit for traumatic indications during the study period were included in the cohort.

PREDICTOR VARIABLES

Four plating styles, surgical approach (transorbital vs transantral), days from injury to first surgery, fracture size (approximated as a rectangle using linear measurements from computed tomography scans), anteroposterior fracture position, and medial wall involvement were examined.

OUTCOME VARIABLES

The primary outcome variable was intraoperative difficulty (defined as requiring revision after intraoperative imaging or return to the operating room). Secondary outcome variables included operating time and postoperative examination abnormalities.

COVARIATES

Age and sex were included.

ANALYSES

χ2 and Regression analyses were performed using a significance level of P < .05.

RESULTS

One hundred and sixty four orbital operations were performed (90 isolated injuries and 74 combined orbital/midface injuries) on 155 subjects (73% male, mean age 39.8 years, standard deviation 16.7). In subjects with isolated orbital fractures, medial wall involvement was associated with intraoperative difficulty (P = .01). When using a transantral approach, intraoperative difficulty was more likely in more anterior fractures (P = .02). Plating style was associated with operating time (P = .03), with median times from 81 to 105 minutes (range 21 to 248 minutes). Postoperative examination abnormalities were more likely in the transorbital approach group (P = .01). Neither days to first surgery nor intraoperative difficulty were associated with postoperative examination abnormalities. Postoperative eyelid changes were seen in 13.6% of transorbital approaches and 0% of transantral approaches. Correction of gaze restriction and enophthalmos were more likely than correction of diplopia (P < .01).

CONCLUSIONS AND RELEVANCE

Medial wall involvement is associated with intraoperative difficulty in orbital surgery. Anteriorly positioned fractures are better treated transorbitally, while posterior fractures may be amenable to transantral repair, thus avoiding risk of lower eyelid changes.

Intraoperative Computed Tomography Use in Orbital Fracture Repair: A Systematic Review and Meta-Analysis

Background: Intraoperative computed tomography (CT) allows surgeons to make adjustments during orbital fracture repair that may impact postoperative outcomes. Learning/Study Objectives: To determine the impact of intraoperative CT use on intraoperative revision and surgical outcomes for orbital fracture repair. Methods: A systematic review was performed in concordance with the Preferred Reporting Items of Systematic Reviews and Meta-Analyses (PRISMA) guidelines: the population was patients undergoing orbital fracture repair; intervention was use of intraoperative CT; comparison was patients not undergoing intraoperative CT; and outcomes were intraoperative revision rate, postoperative complications, and secondary revision surgeries. Meta-analysis was performed on the rate of intraoperative revision. Results: The search criteria yielded 790 articles, 377 were eligible for review, and 20 articles met criteria for analysis. In 19, intraoperative imaging led to immediate surgical corrections, with a random pooled effect size of 0.27 (0.20-0.35). Six studies reported secondary revision surgery rates (range 0-10.5%), and six studies reported postoperative complication rates (range 10-30%). Conclusions: Intraoperative imaging helps surgeons make precise, real-time adjustments in 27% of orbital fracture repair cases, which may improve surgical outcomes; however, more research is needed to investigate its impact on health care costs, operating time, and radiation exposure.

Diagnostic accuracy of ultra-low-dose CT compared to standard-dose CT for identification of non-displaced fractures of the shoulder, knee, ankle, and wrist

OBJECTIVES

To compare the performance of ultra-low-dose computed tomography (ULD-CT) with standard-dose computed tomography (SD-CT) for the diagnosis of non-displaced fractures of the shoulder, knee, ankle, and wrist.

METHODS

This prospective study enrolled 92 patients receiving conservative treatment for limb joint fractures who underwent SD-CT followed by ULD-CT at a mean interval of 8.85 ± 1.98 days. Fractures were characterized as displaced or non-displaced. Objective (signal-to-noise ratio, contrast-to-noise ratio) and subjective CT image quality were evaluated. Observer performance for ULD-CT and SD-CT detecting non-displaced fractures was estimated by calculating the area under the receiver operating characteristic (ROC) curve (A_z).

RESULTS

The effective dose (ED) for the ULD-CT protocol was significantly lower than the ED for the SD-CT protocol (F = 422.21~2112.25, p < 0.0001); 56 patients (65 fractured bones) had displaced fractures, and 36 patients (43 fractured bones) had non-displaced fractures. Two non-displaced fractures were missed by SD-CT. Four non-displaced fractures were missed by ULD-CT. Objective and subjective CT image quality was significantly improved for SD-CT compared to ULD-CT. The sensitivity, specificity, PPV, NPV, and diagnostic accuracy of SD-CT and ULD-CT for non-displaced fractures of the shoulder, knee, ankle and wrist were similar: 95.35% and 90.70%; 100% and 100%; 100% and 100%; 99.72% and 99.44%; and 99.74% and 99.47%, respectively. The A_z was 0.98 for SD-CT and 0.95 for ULD-CT (p = 0.32).

CONCLUSION

ULD-CT has utility for the diagnosis of non-displaced fractures of the shoulder, knee, ankle, and wrist and can support clinical decision-making.

Image-Guided Surgery in Complex Skull Base and Facial Fractures: Initial Experience on the Role of Intra-Operative Computer Tomography

Surgery of fractures involving the skull base and the facial skeleton often presents challenges that should be addressed to prevent secondary brain injuries (i.e., cerebro-spinal fluid leak), preserve visual functioning, and guarantee a good esthetic result. Complex craniofacial reconstruction can be aided by navigation and pre-operative planning. In recent years, computerized planning of surgical reconstruction drastically increased the safety and efficacy of surgery, but the impact of intraoperative high quality image devices such as an intraoperative computed tomography (CT) scan has not been investigated yet. This case-control study reports the institutional preliminary experience of using intraoperative CT scans in the surgical management of complex cranio-facial fractures. The results in terms of accuracy of bony reconstruction and neurological or surgical complications have been analyzed in 12 consecutive patients treated with (6 cases) or without (6 cases) i-CT. Comparative analysis demonstrated a greater accuracy of reconstruction in patients treated with the assistance of i-CT. Intraoperative CT is a useful tool with a promising role in a multidisciplinary surgical approach to complex cranio-facial surgery.

Patient-specific implants in orbital reconstruction

PURPOSE OF REVIEW

Advances in the use of patient-specific implants (PSIs) and virtual surgical planning (VSP) for reconstruction of primary and secondary traumatic orbital defects are explored.

RECENT FINDINGS

PSIs and VSP are emerging technologies that promise to make complex orbital reconstructions safer and more predictable for patients. Recent studies highlight principles of implant design, the novel use of multiunit implant constructs, and utility of intraoperative imaging adjuncts to achieve favorable outcomes.

SUMMARY

This article summarizes recent developments in PSIs for orbital reconstruction. A complete workflow including presurgical planning, execution in the operating room, postoperative analysis, and avoidance of common pitfalls and implant design errors are reviewed.

Bone grafting in maxillofacial trauma

PURPOSE OF REVIEW

The purpose of this article is to review the recent grafting strategies in maxillofacial trauma.

RECENT FINDINGS

Recent technological advancements have applications in the management of maxillofacial trauma; advancements in imaging modalities such as 3D imaging can help surgeons in both the preoperative and intraoperative periods. These may be coupled with navigational systems to further facilitate complex reconstructions. 3D printing has been used in reconstruction and 3D, 4D, and 5D bioprinting technologies continue to improve and to find new uses, and stem cells and growth factors in maxillofacial trauma are also among the most studied topics. Maxillofacial traumas have decreased in number during the COVID-19 pandemic, as more conservative approaches have been preferred in COVID pandemic conditions.

SUMMARY

Preoperative planning is the most important step in the reconstruction of maxillofacial trauma defects, and early bone and soft tissue reconstructions are recommended in severe maxillofacial traumas. Autogenous grafts are the gold standard in bone grafting. Nonvascularized grafts are planned according to the size, shape, and location of the defect, with vascularized bone flaps preferred in large defects, wide soft tissue defects, and contaminated defects. Alloplastic grafts or xenografts may be used if autogenous grafts are not available.

Three-Dimensional Printed Customized Surgical Guides for the Precise Correction of Complex Midfacial Post-Traumatic Deformities

PURPOSE

The introduction of intraoperative computed tomography and image-guided navigation have demonstrated some advantages for the correction of midfacial post-traumatic deformities. However, these methods still do not achieve satisfactory results. The authors sought to describe a novel method for the precise correction of complex midfacial post-traumatic deformities using three-dimensional printing customized surgical guides.

METHODS

Ten patients with midfacial post-traumatic deformities admitted between January 15, 2018 and August 20, 2020 were included. To design the surgical guide for each patient, preoperative planning and simulation datasets were used as a virtual template. Each surgical guide comprised three-dimensional printing cutting guides and customized titanium plates to guide the osteotomy and repositioning of the fracture fragments intraoperatively. Reduction and fixation were confirmed by intraoperative navigation. Postoperative deviation chromatography analysis and clinical examination were conducted to evaluate the surgical outcome. All operations were successfully performed.

RESULTS

The average difference between the virtual plans and postoperative results was less than 1.5 mm. The 3- to 6-month follow-up evaluation demonstrated that symptoms were alleviated, and postoperative function and esthetics improved considerably.

CONCLUSIONS

Three-dimensional-printed customized surgical guides can accurately and effectively transfer the virtual surgical plan to the patient and could be considered an ideal and valuable option for this potentially complicated procedure.

The diagnostic performance of ultra-low-dose 320-row detector CT with different reconstruction algorithms on limb joint fractures in the emergency department

BACKGROUND

The aim of the study was to evaluate whether ultra-low-dose computed tomography (ULD-CT) could replace conventional-dose CT (CD-CT) for diagnosis of acute wrist, ankle, knee, and shoulder fractures in emergency departments (ED).

METHODS

We developed CD-CT and ULD-CT scanning schemes for the various joints of the four limbs and scanned emergency patients prospectively. When performing CD-CT, a conventional bone reconstruction algorithm was used, while ULD-CT used both soft tissue and bone algorithms. A five-point scale was used to evaluate whether ULD-CT image quality affected surgical planning. The image quality and diagnostic performance of different types of scanned and reconstructed images for diagnosing fractures were evaluated and compared. Effective radiation dose of each group was calculated.

RESULTS

Our study included 56 normal cases and 185 fracture cases. The combination of bone and soft tissue algorithms on ULD-CT can improve diagnostic performance, such that on ULD-CT, the sensitivity improved from 96.7% to 98.9%, specificity from 98.2% to 100%, positive predictive value from 99.4% to 100%, negative predictive value from 90.2% to 96.6% and diagnostic accuracy ranged from 97.5% to 99.1%. There were no statistically significant differences between ULD-CT and CD-CT on diagnostic performance (p values, 0.40-1.00). The radiation doses for ULD-CT protocols were only 3.0-7.7% of those for CD-CT protocols (all p < 0.01).

CONCLUSIONS

In the emergency department, the 320-row detector ULD-CT could replace CD-CT in the diagnosis of limb joint fractures. The combination of bone algorithm with soft tissue algorithm reconstruction can further improve the image quality and diagnostic performance.

Secondary Correction of Posttraumatic Enophthalmos

Posttraumatic enophthalmos (PE) arises when the ocular globe is displaced posteriorly and inferiorly in the orbital cavity due to a mismatch in orbital volume and orbital content. This most commonly happens after orbital fractures. The resulting disruptions to aesthetic form and ocular functions often necessitate surgical correction for reconstruction and restoration. The purpose of surgical management of PE is to reconstruct orbital shape and volume as well as to restore any herniated orbital content. This can be particularly challenging in cases involving large defects that require complex orbital reconstruction. Recent advancements in computer-aided surgery have introduced innovative and important tools to assist surgeons with these difficult cases. The ability to create customized, patient-specific implants can facilitate reconstruction involving complicated anatomy. Additionally, intraoperative imaging and intraoperative navigation can serve as useful guides for surgeons to more accurately place implants, especially in cases with limited visualization, in order to achieve optimal outcomes.

The use of computed tomography in the management of injury in tertiary emergency departments in Western Australia: Evidence of overtesting?

BACKGROUND

This study investigated trends in computed tomography (CT) utilization across different triage categories of injury presentations to tertiary emergency departments (EDs) and associations with diagnostic yield measured by injury severity, hospitalization and length of stay (LOS), and mortality.

METHODS

A total of 411,155 injury-related ED presentations extracted from linked records from Western Australia from 2004 to 2015 were included in the retrospective study. The use of CT scanning and diagnostic yield measured by rate of diagnosis with severe injury, hospitalizations and LOS, and mortality were captured annually for injury-related ED presentations. Multivariable regression models were used to calculate the annual adjusted rate of CT scanning for injury presentations and hospitalizations across triage categories, diagnosis with severe injury, LOS, and mortality. The significance of changes observed was compared among patients with CT imaging relative to those without CT.

RESULTS

While the number of ED presentations with injury increased by 65% from 2004 to 2015, the use of CT scanning in these presentations increased by 176%. The largest increase in CT use was among ED presentations triaged as semi-/nonurgent (+256%). Injury presentations with CT, compared to those without, had a higher rate of diagnosis with moderate/severe injury and hospitalization but no difference in LOS and mortality. The probability/rate observed in the outcomes of interest had a greater decrease over time in those with CT scanning compared with those without CT scanning across triage categories.

CONCLUSIONS

The reduction in diagnostic yield in terms of injury severity and hospitalization found in our study might indicate a shift toward overtesting using CT in ED for injury or a higher use of CT to assist in the management of injuries. This helps health care policymakers consider whether the current increase in CT use meets the desired levels of quality and efficient care.

Mandibular Fractures: Diagnosis and Management

Accurate evaluation, diagnosis, and management of mandibular fractures is essential to effectively restore an individual's facial esthetics and function. Understanding of surgical anatomy, fracture fixation principles, and the nuances of specific fractures with respect to various patient populations can aid in adequately avoiding complications such as malocclusion, non-union, paresthesia, and revision procedures. This article reviews comprehensive mandibular fracture assessment, mandibular surgical anatomy, fracture fixation principles, management considerations, and commonly encountered complications. In addition, this article reviews emerging literature examining 3-dimensional printing and intraoperative imaging.

Approach to Orbital Fractures After Athletic Injuries

The bony orbit is commonly involved in athletic injuries. Evaluation should include a comprehensive history and ocular examination. Computed tomography imaging is the gold standard for diagnostic testing. Urgent surgical intervention for orbital floor fractures should occur after "white eye" trapdoor fractures or if oculocardiac response occurs. Most orbital fractures do not require urgent intervention and repair can be completed within 2 weeks of injury. There are many approaches to repair orbital fractures, and consideration of techniques depends on the unique fracture pattern. Intraoperative computed tomography has become frequently used and can lead to increased identification of plate malpositioning intraoperatively.

Correction of Traumatic Transverse Mandibular Widening With Interdental Wiring

ABSTRACT

Mandibular symphysis fractures pose several technical challenges for the craniomaxillofacial surgeon. One classic challenge is restoration of the transverse dimension when the mandible is widened secondary to splaying of the lingual cortex. Failure to diagnose or correct this problem can result in widening of the lower facial third, inadequate fracture reduction, and/or a malocclusion. Surgeons have traditionally utilized techniques such as manual pressure to the rami or lingual splint application to address transverse defects intraoperatively. However, these methods may be inadequate in situations with significant widening, such as in the case of concomitant subcondylar fractures. More recently, virtual surgical planning and custom hardware have been utilized to address mandibular widening, though this method also has various shortcomings. In this technical note, the authors present a simple technique using interdental wiring to precisely control mandibular width intraoperatively. The technique is cost effective, does not require an assistant, and can be used in conjunction with any of the above methods. The authors also present a case of secondary reconstruction in which use of this technique was necessary given a large degree of mandibular widening not amenable to reduction and fixation with manual pressure alone.

The Use of Intraoperative Digital Radiography Alignment Software to Assess Implant Placement in Total Hip Arthroplasty

PURPOSE OF REVIEW

Total hip arthroplasty (THA) is a highly successful surgery with growing rates of utilization in the USA, but surgical outliers leading to postoperative complications remain a concern. There is need for a standard system of accurate, predictable intraoperative evaluation to decrease component positioning outliers. Many current intraoperative imaging systems have shown promise, but there are drawbacks that have led to slow adoption. Digital radiography, in conjunction with Radlink™ technology, is a potential solution to this problem. This review summarizes the clinical application and scientific literature regarding the use of Radlink™ in THA.

RECENT FINDINGS

Traditional surgeon-directed component placement can result in surgical outliers. This is especially true not only among low-volume arthroplasty surgeons, but can also occur with experienced, high-volume surgeons. Digital radiography allows for more precise and accurate placement of the acetabular cup in a targeted range in an effort to improve THA outcomes. Intraoperative images are obtained quickly, and they are accurate when compared to postoperative images. Additionally, the use of Radlink™ results in a significant decrease in leg length and femoral offset outliers. The adoption of Radlink™ technology in THA can significantly decrease surgical outliers, especially errors in acetabular cup placement, leg length, and femoral offset. Digital radiography avoids many of the previous aversions to intraoperative imaging as it produces a fast, reliable image with little radiation exposure and minimal interruption to workflow. There is the potential for Radlink™ use to provide superior patient outcomes, as a decrease in surgical outliers can minimize implant malpositioning with resultant need for revision THAs. Radlink™ may also provide benefit in analyzing other parameters, such as component sizing.

Zygomaticomaxillary complex fracture repair with intraoperative CBCT imaging. A prospective cohort study

The aim of this study was to evaluate the value of intraoperative conebeam computed tomography (CBCT) imaging in the treatment of zygomaticomaxillary complex (ZMC) fractures. A prospective single center cohort study was performed. Included were consecutive patients who underwent surgery for a unilateral ZMC fracture. An intraoperative CBCT scan was performed after reduction of the ZMC fracture. Revision reduction was performed of the ZMC and/or orbital floor (OF) on indication. The preoperative and postoperative asymmetry of the outer surface of the ZMC was measured on digital 3D-models of CBCT scans, using a mirroring and surface-based matching technique. The postoperative asymmetry of the ZMC in the study group was compared to the asymmetry of the ZMC in the control group with healthy individuals. A total of 38 patients with a unilateral ZMC fracture were included. The mean postoperative asymmetry in the study group (1.67 mm, SD 0.89) was less than the mean preoperative asymmetry (2.69 mm, SD 0.95) (paired samples T-test p < 0.01) but showed no statistically significant difference with the mean asymmetry in the healthy control group (1.40 mm, SD 0.54) (independent samples T-test p = 0.31). Revision reduction of the ZMC and/or OF fracture had been performed in 11 cases after malalignment was noted on the intraoperative CBCT. The indication for intraoperative revision reduction was associated with comminuted ZMC fractures and/or fractures with indication for OF reduction (Pearson Chi Square p < 0.01). Within the limitations of the study, intraoperative CBCT imaging seemed to have a positive influence on ZMC fracture treatment, especially in the case of comminuted ZMC fractures and/or fractures with indication for OF treatment.

Imaging in Oral and Maxillofacial Surgery

The scope of oral and maxillofacial surgery treatment and care is very broad, from dentoalveolar surgery, to pathology and reconstruction, to treatment of craniofacial deformities. The effective surgical treatment of patients requires appropriate and accurate diagnostic imaging. The various imaging modalities used in oral and maxillofacial surgery are typically for diagnostic and treatment planning purposes. With the improvements of three-dimensional imaging and software programs, surgical treatment and care have been enhanced with patient-specific guides, hardware, and implants. This article discusses the various imaging modalities used for a variety of typical oral and maxillofacial surgery procedures.

Imaging-based navigation technologies in head and neck surgery

PURPOSE OF REVIEW

Image guided navigation has had significant impact in head and neck surgery, and has been most prolific in endonasal surgeries. Although conventional image guidance involves static computed tomography (CT) images attained in the preoperative setting, the continual evolution of surgical navigation technologies is fast expanding to incorporate both real-time data and bioinformation that allows for improved precision in surgical guidance. With the rapid advances in technologies, this article allows for a timely review of the current and developing techniques in surgical navigation for head and neck surgery.

RECENT FINDINGS

Current advances for cross-sectional-based image-guided surgery include fusion of CT with other imaging modalities (e.g., magnetic resonance imaging and positron emission tomography) as well as the uptake in intraoperative real-time 'on the table' imaging (e.g., cone-beam CT). These advances, together with the integration of virtual/augmented reality, enable potential enhancements in surgical navigation. In addition to the advances in radiological imaging, the development of optical modalities such as fluorescence and spectroscopy techniques further allows the assimilation of biological data to improve navigation particularly for head and neck surgery.

SUMMARY

The steady development of radiological and optical imaging techniques shows great promise in changing the paradigm of head and neck surgery.

Implications of Applying New Technology in Cosmetic and Reconstructive Facial Plastic Surgery

The field of facial plastic and reconstructive surgery is privy to a myriad of technological advancements. As innovation in areas such as imaging, computer applications, and biomaterials progresses at breakneck speed, the potential for clinical application is endless. This review of recent progress in the implementation of new technologies in facial plastic surgery highlights some of the most innovative and impactful developments in the past few years of literature. Patient-specific surgical modeling has become the gold standard for oncologic and posttraumatic reconstructive surgery, with demonstrated improvements in operative times, restoration of anatomical structure, and patient satisfaction. Similarly, reductions in revision rates with improvements in learner technical proficiency have been noted with the use of patient-specific models in free flap reconstruction. In the cosmetic realm, simulation-based rhinoplasty implants have drastically reduced operative times while concurrently raising patient postoperative ratings of cosmetic appearance. Intraoperative imaging has also seen recent expansion in its adoption driven largely by reports of eradication of postoperative imaging and secondary-often complicated-revision reconstructions. A burgeoning area likely to deliver many advances in years to come is the integration of bioprinting into reconstructive surgery. Although yet to clearly make the translational leap, the implications of easily generatable induced pluripotent stem cells in replacing autologous, cadaveric, or synthetic tissues in surgical reconstruction are remarkable.

Does Intraoperative Computed Tomography Scanning in Maxillofacial Trauma Surgery Affect the Revision Rate?

PURPOSE

The purpose of this study was to determine how intraoperative computed tomography affects the intraoperative revision rate and consequently the post-operative, secondary corrective surgery in maxillofacial trauma surgeries.

PATIENTS AND METHODS

A retrospective study composed of patients with facial fractures was conducted in Prince Sultan Military Medical City in Riyadh, Saudi Arabia. The predictor variables were age, gender, site of facial fracture, type of treatment, number of scans per patient, and discharge time. The primary outcome variable was immediate intraoperative revision rate. Secondary outcome variable was total scanning time (recorded from the moment surgery was halted until it was resumed after image acquisition). Descriptive statistics were used; numerical data presented as mean ± SD and categorical variables as frequency (%).

RESULTS

A total of 22 patients underwent 25 intraoperative scans while undergoing different maxillofacial surgeries. Eleven (50%) required intraoperative revisions after the scans, and 3 (13.6%) cases had another intraoperative scan after revision. Eighteen were men and 4 were women. The mean age was 30 years and age range was 19 to 76. Cases were categorized by fracture location and treatment preformed. The mean scanning time was 18.9 ± 4.6 minutes. The highest rate of revisions was seen in zygomaticomaxillary complex fractures (63.6%), they were also the only cases that required a second intraoperative scan after revision to confirm final reduction. No complications were seen postoperatively, and all patients recovered uneventfully. None of the patients required a secondary corrective surgery. All patients were discharged on the following day, except 1 case which was admitted under another service.

CONCLUSIONS

The use of intraoperative computed tomography imaging in treating maxillofacial fractures results in a higher rate of intraoperative revisions, which in turn leads to more accurate fracture reduction and consequently reduces the possibility of a postoperative, secondary corrective surgery.

The Application of Intraoperative Computed Tomography in Surgical Management of Temporomandibular Joint Ankylosis

PURPOSE

To investigate the application and value of intraoperative computed tomography (CT) in the surgical management of temporomandibular joint (TMJ) ankylosis.

PATIENTS AND METHODS

Patients who underwent surgery of TMJ ankylosis with the aid of intraoperative CT scan from July 2016 to December 2018 were retrospectively studied. Demographics, type of ankylosis, surgical method, intraoperative CT scan time, radiographic evidence, the CT-directed revision rate, and clinical outcomes were analyzed.

RESULTS

Four patients (5 sides) were successfully operated with the aid of intraoperative CT imaging, and CT-directed revisions were made in 3 of them during surgery. The average time spent in CT scanning was (10.2 ± 3.3) minutes. No surgical complications were noted, and a good satisfaction rate (with an average maximum mouth opening of 38.8 mm and no recurrence during the follow-up period) was obtained.

CONCLUSIONS

Intraoperative CT scanning is a helpful tool in the evaluation of the radiographic result of TMJ ankylosis, and a real-time revision could be made. It increased the precision and safety of the surgery of TMJ ankylosis.

Management of Zygomaticomaxillary Complex Fractures Utilizing Intraoperative 3-Dimensional Imaging: The ZYGOMAS Protocol

PURPOSE

Utilization of technology to aid in the assessment, planning, and management of complex craniomaxillofacial injuries is increasingly common. Limited data exist regarding the implication of intraoperative CT/3-Dimensional imaging on decision making in the management of zygomaticomaxillary complex (ZMC) fractures. This study characterizes the utilization of the intraoperative CT scanner for ZMC fracture surgery and analyzes the impact of the intraoperative CT scanner on fracture management. Using these findings, we sought to propose an algorithm to guide the appropriate utilization of intraoperative 3-Dimensional imaging in ZMC fracture surgery.

METHODS

This retrospective case series evaluates the use of the intraoperative CT scanner for orbitozygomatic trauma surgery at a level 1 trauma center from February 2011 to September 2016. We evaluated the preoperative CT images assessing for the number of displaced sutures, the presence of adjacent fractures requiring fixation, the presence of comminution of the zygomaticomaxillary buttress or body of the zygoma, as well as the number of axes displaced ≥ 5 mm. This information was evaluated to provide guidance on the appropriate utilization of the intraoperative scanner in ZMC fracture management.

RESULTS

A total of 71 patients were identified to have intraoperative facial CT scans and surgery for ZMC fractures over the study time period. There was a 23.9% (17/71) CT directed revision rate. There was a significantly increased likelihood of CT directed revision for fractures with adjacent fractures requiring fixation, and those with ≥ 2 axes displaced ≥ 5 mm. Using these findings, we proposed the ZYGOMAS algorithm outlining the indications for use of intraoperative CT in management of ZMC fractures.

CONCLUSIONS

If available, intraoperative CT/3-Dimensional imaging should be utilized in the management of ZMC fractures with the requirement for orbital floor reconstruction, where adjacent fractures require fixation and/or when ≥ 2 axes are displaced ≥ 5 mm.

Clinical outcome following intraoperative computed tomography-assisted secondary orbital reconstruction

BACKGROUND

Secondary post-traumatic orbital reconstructions are challenging. Portable computed tomography (CT) provides the option to acquire real-time, intraoperative images that help to detect the insufficient reconstruction of the orbit immediately. We retrospectively analyzed patients who received intraoperative CT imaging and analyzed the effect of intraoperative CT scans on revision rates and orbital volume changes before, during, and after surgery.

METHODS

From August 2014 to September 2016, eleven patients received intraoperative cone-beam CT scans to evaluate the results of secondary orbit reconstruction using Medpor + titanium implants. Patient demographics, surgical details, CT scanning protocol, and follow-up results were analyzed. 3D CT volumetry was used to analyze the orbital volume based on OsiriX MD software.

RESULTS

Based on intraoperative CT findings, seven cases required intraoperative revision to further augment the orbital cavity or adjust implants. The mean preoperative measured enophthalmos was 3.41±1.4 mm (range: 2-6 mm), which decreased to 0.73±0.4 mm (range: 0-1 mm) at postop assessment (p<0.0001). On the fracture side, there was a significant difference between preoperative vs. intraoperative and preoperative vs. postoperative volume measurements (p<0.01 for both subsets), but no significant difference between intraoperative vs. postoperative measurements.

CONCLUSION

Intraoperative CT is a valuable tool in secondary orbital reconstruction cases based on clinical enophthalmos evaluation and 3D CT volumetry. For these patients, the avoidance of another revision surgery may outweigh the disadvantage of increased operation time and additional radiation exposure.

Intraoperative Fluoroscopy Reduces Complication and Reoperation Rate in Facial Fractures

Purpose: The purpose of this study is to evaluate surgical outcomes of facial fractures after the introduction of intraoperative radiology. Methods: An historic cohort of patients without intraoperative fluoroscopy (IOF) was compared with a prospective cohort of patients with IOF. Main outcomes were postoperative complications and reoperation rate. Results: There were 51 in the non-IOF group and 49 in the IOF group. In the group with IOF 10 patients required intraoperative revisions (20.46%). Overall postoperative complication rate was higher in the non-IOF group (25.49% vs. 6.12%) due to the significantly higher bone-related complication rate (15.69% vs. 2.04%). Reoperation rate was also higher in the non-IOF group (11.76% vs. 0%). Conclusion: This study demonstrates that IOF reduces bone-related complication and reoperation rate by allowing correction of surgical errors immediately during surgery.

Low-Dose Computed Tomographic Scans for Postoperative Evaluation of Craniomaxillofacial Fractures: A Pilot Clinical Study

Computed tomographic scans are frequently obtained following craniomaxillofacial fracture reconstruction. The additive radiation from such scans is not trivial; cumulative radiation exposure poses stochastic health risks. In this article, the authors postulate that a low-dose computed tomography protocol provides adequate image quality for postoperative evaluation of reconstructed craniomaxillofacial fractures. This study included patients for whom a computed tomographic scan was indicated following craniomaxillofacial fracture repair at a Level I trauma center. Postoperative craniomaxillofacial computed tomography was performed using a low-dose protocol, rather than standard protocols. A craniomaxillofacial surgeon and a radiologist interpreted the images to determine whether they were of sufficient quality. It was decided a priori that any inadequate low-dose computed tomography would require repeated scanning using standard protocols. The primary endpoint was the need for repeated computed tomography. In addition, the clarity of clinically significant anatomical landmarks on the images was graded on a five-point Likert scale. Twenty patients were scanned postoperatively using the low-dose protocol. Mean radiation dose (total dose-length product) from the low-dose protocol was 71 mGy · cm versus 532 mGy · cm for the preoperative computed tomographic scans that were obtained using conventional protocols (p < 0.001). All 20 low-dose computed tomographic scans were determined to provide satisfactory image quality. No patients required repeated computed tomography secondary to poor image quality. Low-dose computed tomography received high image-quality scores. A low-dose computed tomography protocol that delivers approximately 7.5-fold less radiation than the standard protocols was found to be adequate for postoperative evaluation of craniomaxillofacial fractures. Larger prospective studies may be warranted. CLINICAL QUESTION/LEVEL OF EVIDENCE:: Therapeutic, IV.

Surgical management of isolated orbital floor and zygomaticomaxillary complex fractures with focus on surgical approaches and complications

Zygomaticomaxillary complex (ZMC) and orbital blow out fractures are commonly encountered midfacial fractures that may result in aesthetic and functional impairment. This retrospective study reports on the surgical treatment and associated postoperative complications in our patient collective. We evaluated 100 patients who underwent open reduction and internal fixation of midfacial fractures between 2010 and 2015. Preoperative clinical features, surgical technique and postoperative complications were analyzed. Surgery was performed with a mean latency of 7 days after trauma. We used titanium mesh and polydioxanone sheets to reconstruct the orbital floor. Most ZMC fractures were stabilized with two point fixation with titanium plates. Preoperative symptoms were present in 70 patients (70%). Infraorbital hypesthesia occurred in 49 patients, diplopia in 41 patients and ocular motility impairment in 24 patients. Postoperative symptoms persisted during a mean follow-up time of 4.5 months in 47 patients (47%) showing infraorbital hypesthesia in 24%, diplopia in 17%, ectropion in 7% and ocular motility impairment in 4%. Complications requiring revision were retrobulbar hematoma 3% (n = 3), ectropion 3% (n = 3), diplopia 1% (n = 1), exophthalmos 1% (n = 1), implant dislocation 1% (n = 1), implant discomfort 2% (n = 2), persisting fracture dislocation 1% (n = 1). All patients recovered without significant impairment. Surgery is required in the majority of the patients with midfacial fractures. Among others ectropion is challenging due to its aesthetic and functional impact on patients. To prevent ectropion, additional canthopexy or the transconjunctival surgical approach are reasonable options in selected cases. Level of Evidence: Level V, descriptive study. AbbreviationsCTcomputed tomographyOForbital floorPDSpolydioxanoneORIFopen reduction and internal fixationZMCzygomaticomaxillary complex.

Complications Following Orbital Floor Repair: Impact of Intraoperative Computed Tomography Scan and Implant Material

Importance: Orbital floor fracture repair is complex and postoperative complications are common. A variety of applicable surgical techniques and technologies are available to surgeons, so data about which of these may decrease postoperative complication rates can help better guide clinical decision making. Objectives: To characterize the patient demographics and surgical techniques utilized in orbital floor fracture repairs at San Antonio Military Medical Center and their relationship with rates of postoperative complications. Design, Setting, and Participants: Retrospective chart review of patients who underwent orbital floor fracture repairs from March 2014 to March 2019 with a mean follow-up time of 1.86 months at a tertiary care academic military hospital and level 1 trauma center. Main Outcomes and Measures: Demographic data, indication for surgical repair, fracture severity, orbital floor approach, implant material, and use of intraoperative computed tomography (CT) scan were recorded. Chi-square analysis was performed to determine the relationship between these factors and postoperative diplopia, hypoglobus, enophthalmos, and infection. Results: A total of 124 procedures were performed during the study period: 71.8% of patients were male and 74% were civilian. Mean age was 39 years (range 19-81). Thirty-one patients were lost to follow-up. The most common approach was transconjunctival (83%), which was most frequently used exclusively (68.5%), but was also combined with cantholysis, transcaruncular, or transantral approach. Postoperative diplopia at follow-up was common (53.8%), resolved after an average of 36.3 days, and was significantly associated with surgical indication of entrapment or revision (p = 0.01) and nonutilization of intraoperative CT (p = 0.04). From 2014 to 2016, intraoperative CT was utilized in 21% of cases and revision rate was 10.5%. From 2017 to 2019, 50% of cases utilized intraoperative CT and revision rate was 2% (p = 0.15). Three cases were revisions performed for abnormal plate position noted on postoperative CT scan. Conclusions and Relevance: A statistically significant association was found between postoperative diplopia, surgical indication of entrapment or revision, and nonutilization of intraoperative CT. Revision rates decreased when use of intraoperative CT increased. Three revision cases may have been prevented by use of an intraoperative CT scan. Patients with entrapment should be counseled regarding the increased risk of postoperative diplopia.

Review of Orbital Fractures in an Urban Level I Trauma Center

Objective

To perform a comprehensive review and analysis of surgically treated orbital fractures.

Study Design

Retrospective cohort chart review study for surgically treated orbital fractures during 5 years.

Results

A total of 173 patients (average age 41.6 years) were diagnosed with orbital fractures. Most were male with a ratio of 3.3:1. Most fractures were caused by assault (39.3%); 22.5% of the cases were bilateral. The left orbit (40.5%) was fractured more than the right. The orbital floor (97.1%) was the most common anatomic location and the maxilla (65.3%) was the most commonly involved bone. The average time from trauma to surgical intervention was 8.7 ± 14.6 days and the average time from surgical intervention to discharge was 5.1 ± 9.0 days. The transconjunctival incision (63%) was the most commonly used incision, and nonresorbable implant (92.7%) was the most commonly used implant. Finally, the length of stay for the repair of a simple orbital fracture was less than for complex orbital fracture (1.5 days and 5.9 days, respectively).

Conclusion

Understanding the patterns and mechanisms of injury associated with orbital fractures can assist in developing standardized treatment protocols across all surgical specialties. This would ultimately allow for a uniform high quality of surgical care for patients with maxillofacial fractures.

Role of Plain Radiographs in Assessing Appropriate Placement of Orbital Implants for Repair of Floor Fractures

Intraoperative imaging is becoming increasingly common in repair of facial fractures. Many institutions do not have access to intraoperative advanced 3D imaging but have the capability of obtaining plain radiographs intraoperatively. At institutions where advanced 3D imaging is available, scout radiographs are usually obtained prior to a complete scan. These scout images can provide some information about the placement of radiopaque implants before a complete scan is performed. The aim of this study is to examine the correct anatomic positioning of an orbital floor implant using lateral plain radiographs. Titanium orbital fan implants were molded and secured to orbital floor of 14 adult dry skulls (7 males and 7 females). Lateral radiographs were obtained for both the left and the right orbits individually. The antero-posterior angle of inclination that the implant makes relative to the Frankfort horizontal plane was measured, and results were compared in the male versus female radiographs. The mean angle that the implant made with the Frankfort horizontal plane was 20.1±2.4° in the male orbits (95% CI 18.8-21.5°) and 22.6 ± 2.0° in the female orbits (95% CI, 21.4-23.7°). We found no statistically significant differences between the male and female angles (P-value 0.62). For the combined specimens (i.e., 28 sides in 14 skulls), the overall mean angle was 21.4 ± 2.5° (95% CI, 20.4-22.3°). Based on these findings, the angle that the implant makes with the Frankfort horizontal plane on lateral cross-table plain radiographs can be used intraoperatively to assist the surgeon in confirming the appropriate placement of the implant.

Computerized Approach to Facial Transplantation: Evolution and Application in 3 Consecutive Face Transplants

Face transplant (FT) candidates present with unique anatomic and functional defects unsuitable for autologous reconstruction, making the accurate design and transplantation of patient-specific allografts particularly challenging. In this case series, we present our computerized surgical planning (CSP) protocol for FT.

Intraoperative Computed Tomography Scan for Orbital Fracture Reconstruction

Orbital fractures pose specific challenge in its surgical management. One of the greatest challenges is to obtain satisfactory reconstruction by correct positioning of orbital implant. Intraoperative computed tomography (CT) scan may facilitate this procedure. The aim of this study was to describe the early use of intraoperative CT in orbital fractures repair in our center. The authors assessed the revision types and rates that have occurred with this technique. With the use of pre-surgical planning, optical intraoperative navigation, and intraoperative CT, the impact of intraoperative CT on the management of 5 cases involving a total number of 14 orbital wall fractures were described. There were 6 pure orbital blowout wall fractures reconstructed, involving both medial and inferior wall of the orbit fracturing the transition zone and 8 impure orbital wall fractures in orbitozygomaticomaxillary complex fracture. 4 patients underwent primary and 1 had delayed orbital reconstruction. Intraoperative CT resulted in intraoperative orbital implant revision, following final navigation planning position, in 40% (2/5) of patients or 14% (2/14) of the fractures. In revised cases, both implant repositioning was conducted at posterior ledge of orbit. Intraoperative CT confirmed true to original reconstruction of medial wall, inferior wall and transition zone of the orbit. Two selected cases were illustrated. In conclusion, intraoperative CT allows real-time assessment of fracture reduction and immediate orbital implant revision, especially at posterior ledge. As a result, no postoperative imaging was indicated in any of the patients. Long-term follow-ups for orbital fracture patients managed with intraoperative CT is suggested.