Craniofacial Growth and Development: A Primer for the Facial Trauma Surgeon.

Understanding craniofacial growth and development is important in the management of facial trauma in the growing pediatric patient. This manuscript is a review of craniofacial growth and development and clinical implications of pediatric facial fractures.

Longitudinal diffusion and volumetric kinetics of head and neck cancer magnetic resonance on a 1.5T MR-Linear accelerator hybrid system: A prospective R-IDEAL Stage 2a imaging biomarker characterization/ pre-qualification study.

Objectives: We aim to characterize the serial quantitative apparent diffusion coefficient (ADC) changes of the target disease volume using diffusion-weighted imaging (DWI) acquired weekly during radiation therapy (RT) on a 1.5T MR-Linac and correlate these changes with tumor response and oncologic outcomes for head and neck squamous cell carcinoma (HNSCC) patients as part of a programmatic R-IDEAL biomarker characterization effort. Methods: Thirty patients with pathologically confirmed HNSCC who received curative-intent RT at the University of Texas MD Anderson Cancer Center, were included in this prospective study. Baseline and weekly Magnetic resonance imaging (MRI) (weeks 1-6) were obtained, and various ADC parameters (mean, 5 th , 10 th , 20 th , 30 th , 40 th , 50 th , 60 th , 70 th , 80 th , 90 th and 95 th percentile) were extracted from the target regions of interest (ROIs). Baseline and weekly ADC parameters were correlated with response during RT, loco-regional control, and the development of recurrence using the Mann-Whitney U test. The Wilcoxon signed-rank test was used to compare the weekly ADC versus baseline values. Weekly volumetric changes (Δvolume) for each ROI were correlated with ΔADC using Spearman's Rho test. Recursive partitioning analysis (RPA) was performed to identify the optimal ΔADC threshold associated with different oncologic outcomes. Results: There was an overall significant rise in all ADC parameters during different time points of RT compared to baseline values for both gross primary disease volume (GTV-P) and gross nodal disease volumes (GTV-N). The increased ADC values for GTV-P were statistically significant only for primary tumors achieving complete remission (CR) during RT. RPA identified GTV-P ΔADC 5 th percentile >13% at the 3 rd week of RT as the most significant parameter associated with CR for primary tumor during RT (p <0.001). Baseline ADC parameters for GTV-P and GTV-N didn't significantly correlate with response to RT or other oncologic outcomes. There was a significant decrease in residual volume of both GTV-P & GTV-N throughout the course of RT. Additionally, a significant negative correlation between mean ΔADC and Δvolume for GTV-P at the 3 rd and 4 th week of RT was detected (r = -0.39, p = 0.044 & r = -0.45, p = 0.019, respectively). Conclusion: Assessment of ADC kinetics at regular intervals throughout RT seems to be correlated with RT response. Further studies with larger cohorts and multi-institutional data are needed for validation of ΔADC as a model for prediction of response to RT.

Prospective evaluation of in vivo and phantom repeatability and reproducibility of diffusion-weighted MRI sequences on 1.5 T MRI-linear accelerator (MR-Linac) and MR simulator devices for head and neck cancers.

INTRODUCTION: Diffusion-weighted imaging (DWI) on MRI-linear accelerator (MR-linac) systems can potentially be used for monitoring treatment response and adaptive radiotherapy in head and neck cancers (HNC) but requires extensive validation. We performed technical validation to compare six total DWI sequences on an MR-linac and MR simulator (MR sim) in patients, volunteers, and phantoms. METHODS: Ten human papillomavirus-positive oropharyngeal cancer patients and ten healthy volunteers underwent DWI on a 1.5 T MR-linac with three DWI sequences: echo planar imaging (EPI), split acquisition of fast spin echo signals (SPLICE), and turbo spin echo (TSE). Volunteers were also imaged on a 1.5 T MR sim with three sequences: EPI, BLADE (vendor tradename), and readout segmentation of long variable echo trains (RESOLVE). Participants underwent two scan sessions per device and two repeats of each sequence per session. Repeatability and reproducibility within-subject coefficient of variation (wCV) of mean ADC were calculated for tumors and lymph nodes (patients) and parotid glands (volunteers). ADC bias, repeatability/reproducibility metrics, SNR, and geometric distortion were quantified using a phantom. RESULTS: In vivo repeatability/reproducibility wCV for parotids were 5.41%/6.72%, 3.83%/8.80%, 5.66%/10.03%, 3.44%/5.70%, 5.04%/5.66%, 4.23%/7.36% for EPIMR-linac, SPLICE, TSE, EPIMR sim, BLADE, RESOLVE. Repeatability/reproducibility wCV for EPIMR-linac, SPLICE, TSE were 9.64%/10.28%, 7.84%/8.96%, 7.60%/11.68% for tumors and 7.80%/9.95%, 7.23%/8.48%, 10.82%/10.44% for nodes. All sequences except TSE had phantom ADC biases within ± 0.1x10-3 mm2/s for most vials (EPIMR-linac, SPLICE, and BLADE had 2, 3, and 1 vials out of 13 with larger biases, respectively). SNR of b = 0 images was 87.3, 180.5, 161.3, 171.0, 171.9, 130.2 for EPIMR-linac, SPLICE, TSE, EPIMR sim, BLADE, RESOLVE. CONCLUSION: MR-linac DWI sequences demonstrated near-comparable performance to MR sim sequences and warrant further clinical validation for treatment response assessment in HNC.

Jaw Surgery Workshop: Patient Preparation for Orthognathic Surgery.

BACKGROUND: Patients undergoing orthognathic surgery may have limited information surrounding surgery. This leads to less satisfaction with surgical outcomes, anxiety surrounding surgery and difficulty following perioperative instructions. SOLUTION: Providing a multi-disciplinary pre-operative educational experience for patients and caregivers improves surgical readiness and satisfaction. WHAT IS NEW: Our team provides a "Jaw Surgery Workshop" which includes lectures from providers, previous patients, cookbooks and supplies. This allows for improved confidence and expectations surrounding jaw surgery.

3-Dimensional Craniofacial Imaging: A Template for Systematic Radiologic Evaluation for Alveolar Cleft Assessment and Planning.

BACKGROUND: Imaging findings are central to the diagnosis and treatment planning decisions when managing craniofacial differences. However, limited information is published on protocols for systematic cleft imaging assessment and for effective communication of these findings. SOLUTION: A template is presented to help guide radiologic imaging reports to acquire the relevant clinical information needed to manage patients with alveolar cleft.

Diagnostic Protocols for Alveolar Clefting and Barriers to Acquiring Imaging: A Survey of ACPA-Approved Cleft Teams in the United States.

OBJECTIVE: To report current diagnostic protocols, practices, and barriers related to imaging of alveolar clefting among American Cleft Palate-Craniofacial Association (ACPA)-approved cleft/craniofacial teams. METHODS: An electronic survey was sent to 162 ACPA-approved teams in the United States. Key items were team location, venue of orthodontic treatment, imaging modality(s) and access, barriers to imaging, billing, imaging protocols including team members involved in decisions pre- and post-alveolar bone grafting (ABG), and craniofacial fellowship status of team orthodontist(s). RESULTS: A total of 66 responses were received (40.7%). Responding teams were university-based (47%), hospital-based (42.4%), and independent clinics (10.6%). Orthodontic treatment for most patients was in private practice (53%). On-site 2-dimensional (2D) and 3-dimensional (3D) dental imaging capabilities were reported by 42% of teams; 29% have no on-site imaging. One or more barrier(s) to acquiring imaging were reported by 67%, with insurance challenges reported by 47%. Most teams bill medical payors for cleft-related dental imaging (58%). Pre- and post-ABG imaging was most frequently 3D (35% and 36%, respectively). Surgeons and orthodontists commonly evaluate ABG timing and outcome together (53%-65%). Periapical radiographs were included significantly more often in cleft imaging protocols by orthodontists with versus without fellowship training (P = .011, P = .04). CONCLUSIONS: Barriers to acquiring imaging are frequent. 3D is the most common imaging pre- and post-ABG. Our study endorses multi-level advocacy for improved medical insurance coverage of diagnostic cleft-related dental imaging to decrease barriers to providing timely care.

Orthodontic treatment protocols in patients with alveolar clefting: a survey of ACPA-approved cleft teams in the United States.

OBJECTIVES: To describe pre- and post-alveolar bone graft (ABG) practice protocols of orthodontists associated with American Cleft Palate-Craniofacial Association-approved cleft and cleft/craniofacial teams. MATERIALS AND METHODS: Electronic survey responses from team orthodontists were evaluated regarding pre-ABG orthodontic treatment type(s), timing of post-ABG imaging and post-ABG orthodontic treatment, and craniofacial orthodontic fellowship training status of the team orthodontists. A P value of <.05 was considered significant. RESULTS: Of 31 responding orthodontists, 54.8% had fellowship training and 45.2% did not. Pre-ABG orthodontic preparation ranged from solely maxillary expansion for alveolar segment alignment (35.5%) to a combination of maxillary expansion for both alveolar segment alignment and posterior crossbite correction, anterior tooth alignment, and anterior crossbite correction (19.4%). Most captured post-ABG radiographs prior to orthodontic tooth movement (90.3%). Orthodontists began treatment at least 6 months (35.5%), 2-4 months (32.3%), or 4-6 months (29%) post-ABG. No significant differences were found when comparing fellowship subgroups. In addition, 47.1% of fellowship-trained orthodontists deferred post-ABG orthodontic treatment to at least 6 months post-operatively, vs 21.4% of non-fellowship trained orthodontists (P = .14). CONCLUSIONS: A large variation in approaches is evident in pre-ABG orthodontic treatment types and timing of post-ABG treatment. Post-operative imaging is pursued by most orthodontists to assess graft status prior to initiating orthodontic treatment. Additional clinical research is needed to support providers in their decision-making with regard to evidence-based approaches.

Deep-learning-based generation of synthetic 6-minute MRI from 2-minute MRI for use in head and neck cancer radiotherapy.

Background: Quick magnetic resonance imaging (MRI) scans with low contrast-to-noise ratio are typically acquired for daily MRI-guided radiotherapy setup. However, for patients with head and neck (HN) cancer, these images are often insufficient for discriminating target volumes and organs at risk (OARs). In this study, we investigated a deep learning (DL) approach to generate high-quality synthetic images from low-quality images. Methods: We used 108 unique HN image sets of paired 2-minute T2-weighted scans (2mMRI) and 6-minute T2-weighted scans (6mMRI). 90 image sets (~20,000 slices) were used to train a 2-dimensional generative adversarial DL model that utilized 2mMRI as input and 6mMRI as output. Eighteen image sets were used to test model performance. Similarity metrics, including the mean squared error (MSE), structural similarity index (SSIM), and peak signal-to-noise ratio (PSNR) were calculated between normalized synthetic 6mMRI and ground-truth 6mMRI for all test cases. In addition, a previously trained OAR DL auto-segmentation model was used to segment the right parotid gland, left parotid gland, and mandible on all test case images. Dice similarity coefficients (DSC) were calculated between 2mMRI and either ground-truth 6mMRI or synthetic 6mMRI for each OAR; two one-sided t-tests were applied between the ground-truth and synthetic 6mMRI to determine equivalence. Finally, a visual Turing test using paired ground-truth and synthetic 6mMRI was performed using three clinician observers; the percentage of images that were correctly identified was compared to random chance using proportion equivalence tests. Results: The median similarity metrics across the whole images were 0.19, 0.93, and 33.14 for MSE, SSIM, and PSNR, respectively. The median of DSCs comparing ground-truth vs. synthetic 6mMRI auto-segmented OARs were 0.86 vs. 0.85, 0.84 vs. 0.84, and 0.82 vs. 0.85 for the right parotid gland, left parotid gland, and mandible, respectively (equivalence p<0.05 for all OARs). The percent of images correctly identified was equivalent to chance (p<0.05 for all observers). Conclusions: Using 2mMRI inputs, we demonstrate that DL-generated synthetic 6mMRI outputs have high similarity to ground-truth 6mMRI, but further improvements can be made. Our study facilitates the clinical incorporation of synthetic MRI in MRI-guided radiotherapy.

Proton Image-guided Radiation Assignment for Therapeutic Escalation via Selection of locally advanced head and neck cancer patients [PIRATES]: A Phase I safety and feasibility trial of MRI-guided adaptive particle radiotherapy.

INTRODUCTION: Radiation dose-escalation for head and neck cancer (HNC) patients aiming to improve cure rates is challenging due to the increased risk of unacceptable treatment-induced toxicities. With "Proton Image-guided Radiation Assignment for Therapeutic Escalation via Selection of locally advanced head and neck cancer patients" (PIRATES), we present a novel treatment approach that is designed to facilitate dose-escalation while minimizing the risk of dose-limiting toxicities for locally advanced HPV-negative HNC patients. The aim of this Phase I trial is to assess the safety & feasibility of PIRATES approach. METHODS: The PIRATES protocol employs a multi-faceted dose-escalation approach to minimize the risk of dose-limiting toxicities (DLTs): 1) sparing surrounding normal tissue from extraneous dose with intensity-modulated proton therapy, 2) mid-treatment hybrid hyper-fractionation for radiobiologic normal tissue sparing; 3) Magnetic Resonance Imaging (MRI) guided mid-treatment boost volume adaptation, and 4) iso-effective restricted organ-at-risk dosing to mucosa and bone tissues.The time-to-event Bayesian optimal interval (TITE-BOIN) design is employed to address the challenge of the long DLT window of 6 months and find the maximum tolerated dose. The primary endpoint is unacceptable radiation-induced toxicities (Grade 4, mucositis, dermatitis, or Grade 3 myelopathy, osteoradionecrosis) occurring within 6 months following radiotherapy. The second endpoint is any grade 3 toxicity occurring in 3-6 months after radiation. DISCUSSION: The PIRATES dose-escalation approach is designed to provide a safe avenue to intensify local treatment for HNC patients for whom therapy with conventional radiation dose levels is likely to fail. PIRATES aims to minimize the radiation damage to the tissue surrounding the tumor volume with the combination of proton therapy and adaptive radiotherapy and within the high dose tumor volume with hybrid hyper-fractionation and not boosting mucosal and bone tissues. Ultimately, if successful, PIRATES has the potential to safety increase local control rates in HNC patients with high loco-regional failure risk.Trial registration: ClinicalTrials.gov ID: NCT04870840; Registration date: May 4, 2021.Netherlands Trial Register ID: NL9603; Registration date: July 15, 2021.

Lefort II distraction with zygomatic repositioning versus Lefort III distraction: A comparison of surgical outcomes and complications.

The aim of the study was to determine if the additional surgical complexity of Lefort II distraction with zygomatic repositioning (LF2ZR) results in increased complications compared to Lefort III distraction (LF3). A retrospective review was performed of all LF3 and LF2ZR advancements performed by the senior author over 15 years. Demographic, operative, postoperative, and cephalometric data were collected from initial procedure through greater than 1 year postoperatively. Univariate and multivariate analyses were performed to compare procedures. 19 LF2ZR and 39 LF3 in 53 patients met inclusion criteria. Diagnoses differed between procedures, with more Crouzon Syndrome in LF3 and more Apert Syndrome in LF2ZR. Complication rate was 7/19 for LF2ZR and 12/39 for LF3 with no severe morbidity or mortality, and no difference between procedures (p = 0.56). The types of complications encountered differed between procedures. LF2ZR had a significantly longer operative time (506 ± 18 vs. 358 ± 24 min, p<0.001). However, a greater number of LF2ZR patients underwent concomitant procedures (15/19 vs. 13/39, p<0.001). Multivariate analysis revealed that Apert Syndrome and reoperative midface advancement were the most significant predictors of increased blood loss. LF2ZR has an equivalent complication rate to LF3. Therefore, it is our treatment of choice for cases requiring differential sagittal and vertical distraction of the central midface.

A Communication Guide for Orthodontic-Restorative Collaborations: An Orthodontic Perspective on the Importance of Working in a Team.

As both restorative dentists and specialists have their respective realms of expertise, it is important to develop a team of qualified providers to improve treatment outcomes for patients. In many cases, this involves collaboration between a restorative dentist and orthodontist. Effective communication is critical, with the dentist's understanding of basic orthodontic terminology and case planning considerations. Recognizing the context in which to apply normative occlusal and cephalometric values often necessitates comprehensive specialty-level experience. All providers should recognize when to involve the indicated team members when complex multidisciplinary treatment needs are present. The team approach offers an opportunity to optimize excellent patient care.

Technical Modifications Specific to the Cleft Le Fort I Osteotomy.

PURPOSE: To discuss technical modifications specific to the cleft Le Fort I osteotomy that improve mobilization and demonstrate the stability of the maxilla at the Le Fort I level in a cohort of patients with cleft palate (with or without cleft lip) who underwent traditional maxillary advancement. METHODS: This was a retrospective evaluation of patients with cleft palate (+/- cleft lip) who underwent orthognathic surgery for management of skeletal malocclusions. All study subjects had a Le Fort I osteotomy +/- bilateral mandibular sagittal split osteotomies. The cleft Le Fort I osteotomy technique is modified to extensively release fibrous tissue and scar from the posterior maxilla, including around the tuberosity, along the posterior maxillary sinus wall, and circumferentially around the descending palatine canal. Maxillary position was assessed using angular and linear measurements pre-operatively (T0), immediately post-operatively (T1), and at 1-year post-operatively (T2). Descriptive and bivariate statistics were computed; a P < 0.05 was considered significant. RESULTS: Twenty-eight patients with cleft palate (with or without cleft lip) were included. The sample's mean age was 18.9 ±â€Š1.4 years and included 11 females. The majority of subjects (64.3%) underwent bimaxillary surgery; eight subjects (28.6%) had segmental maxillary surgery and 14 subjects (50%) had simultaneous maxillary interpositional bone grafting. The mean maxillary sagittal advancement was 6.1 mm (range: 0-10 mm). At 1-year post-operatively, the absolute change in SNA was 0.7 ±â€Š0.9 degrees; the absolute change in maxillary sagittal position was 0.8 ±â€Š0.6 mm. There was no association between the magnitude of advancement and the magnitude of position change (P = 0.86). Stability was not influenced by segmental surgery, bone grafting, or bimaxillary surgery (P > 0.33). CONCLUSION: Using a modified technique with extensive release of posterior scar and graduated intra-operative traction, maxillary advancement of up to 10 mm can be performed in patients with cleft palate (± cleft lip) with sagittal relapse of < 1 mm at 1-year post-operatively.

Correction to: Long-term patient reported outcomes following radiation therapy for oropharyngeal cancer: cross-sectional assessment of a prospective symptom survey in patients ≥65 years old.

In the original publication [1] the name of author Jeremy M. Aymard was spelled wrong. The original article was updated to rectify this error.

Long-term patient reported outcomes following radiation therapy for oropharyngeal cancer: cross-sectional assessment of a prospective symptom survey in patients ≥65 years old.

BACKGROUND: Given the potential for older patients to experience exaggerated toxicity and symptoms, this study was performed to characterize patient reported outcomes in older patients following definitive radiation therapy (RT) for oropharyngeal cancer (OPC). METHODS: Cancer-free head and neck cancer survivors (>6 months since treatment completion) were eligible for participation in a questionnaire-based study. Participants completed the MD Anderson Symptom Inventory-Head and Neck module (MDASI-HN). Those patients ≥65 years old at treatment for OPC with definitive RT were included. Individual and overall symptom severity and clinical variables were analyzed. RESULTS: Of the 79 participants analyzed, 82% were male, 95% white, 41% T3/4 disease, 39% RT alone, 27% induction chemotherapy, 52% concurrent, and 18% both, and 96% IMRT. Median age at RT was 71 yrs. (range: 65-85); median time from RT to MDASI-HN was 46 mos. (2/3 > 24 mos.). The top 5 MDASI-HN items rated most severe in terms of mean (±SD) ratings (0-10 scale) were dry mouth (3.48 ± 2.95), taste (2.81 ± 3.29), swallowing (2.59 ± 2.96), mucus in mouth/throat (2.04 ± 2.68), and choking (1.30 ± 2.38) reported at moderate-severe levels (≥5) by 35, 29, 29, 18, and 13%, respectively. Thirty-nine % reported none (0) or no more than mild (1-4) symptoms across all 22 MDASI-HN symptoms items, and 38% had at least one item rated as severe (≥7). Hierarchical cluster analysis resulted in 3 patient groups: 1) ~65% with ranging from none to moderate symptom burden, 2) ~35% with moderate-severe ratings for a subset of classically RT-related symptoms (e.g. dry mouth, mucus, swallowing) and 3) 2 pts. with severe ratings of most items. CONCLUSIONS: The overall long-term symptom burden seen in this older OPC cohort treated with modern standard therapy was largely favorable, yet a higher symptom group (~35%) with a distinct pattern of mostly local and classically RT-related symptoms was identified.