James R. Seaward

Improving the Evaluation of Alveolar Bone Grafts With Cone Beam Computerized Tomography

Objective Cone Beam computed tomography (CBCT) is used increasingly as a replacement for periapical x-rays when evaluating alveolar bone grafting. The manufacturers standard settings for dental imaging may not, however, represent the optimal settings for evaluating postoperative alveolar bone grafts. We examined the influence of exposure parameters on CBCT image quality to optimize the quality of CBCT images while reducing the radiation dose to the minimum level necessary to obtain adequate images. Methods A defect was created in a cadaver head to simulate an alveolar cleft, and the area was filled with a synthetic material to simulate an alveolar bone graft. Serial CBCT scans were acquired, systematically varying tube voltage and tube current settings from 72 to 96kV and 3 to 12mA. Region of interest analysis was undertaken, and image quality was evaluated by comparing the ratios of native alveolar bone to soft tissue and the ratios of synthetic bone graft to soft tissue and by assessing image noise. Results Twenty-one CBCT data sets were obtained. Reducing tube voltage (kV) resulted in increased contrast ratio between bone and soft tissue and between synthetic bone graft and soft tissue, with maximal contrast at values of 76 kV/11 mA, 72 kV/12 mA, and 72 kV/11 mA. Of these, the setting with lowest image noise was 76 kV/11 mA. This setting also resulted in a radiation dose of less than half of the manufacturers recommended settings for the same scan volume. Conclusions There is potential to improve CBCT image quality significantly while dramatically reducing the radiation dose during postoperative examinations for alveolar bone grafting in patients with cleft lip and palate.

Liquid latex molding: A novel application of 3D printing to facilitate flap design

The approach to bony craniofacial reconstruction has been significantly enhanced with the development of patient-specific, computer-aided designed and manufactured (CAD/CAM) implants. This technology, however, has not yet been widely employed for soft tissue reconstruction. While algorithmic approaches based on the size, location, and etiology of the defect are effective in most cases, a patient-specific CAD/CAM approach has benefits in complex reconstructive problems. In this study, we present a patient-specific approach to preoperative flap planning: using three-dimensional (3D) printing and liquid latex to create a flexible model of a flap, and demonstrate its application in planning a complex scalp reconstruction.

Dynamic facial asymmetry in patients with repaired cleft lip using 4D imaging (video stereophotogrammetry)

BACKGROUND Unilateral cleft lip is a profoundly asymmetrical condition affecting all hard and soft tissue layers from the nose to the upper lip. Although the asymmetry is minimized through cleft lip repair, a degree of asymmetry inevitably persists. Studies investigating asymmetry in patients with cleft lip have used facial measurements, and static 2D and 3D photography. The nose/lip/mouth area, however, is rarely static in our day to day social interactions. METHODS Non-syndromic patients with cleft lip and palate, and a control group without orofacial clefts underwent 50 frames per second 4D imaging while generating facial expressions including smiling and pouting. Key landmarks were tracked throughout the expression, corrected for head movement and a motion path of each landmark was generated. Asymmetry was assessed for both extent of displacement, using Euclidean distances between frames, and the shape of the motion path using Procrustes analysis. RESULTS Twelve patients were compared in each group with an age range from 8 to 18. Comparing the motion path of key landmarks in the upper lip demonstrated statistically significant differences in both the magnitude and shape of motion during smiling and pouting between cleft and non-cleft groups. CONCLUSION Video stereophotogrammetry of the repaired cleft lip demonstrates asymmetry of both the magnitude of motion as well as asymmetry of the path of the motion itself. This may be due to the effect of the scar tissue from the repair, from the abnormal anatomy involved with cleft lip or a combination of the two.

Ionizing Radiation in Craniofacial Surgery: A Primer on Dose and Risks

An understanding of radiation dose and the anticipated risk to the patient is an important aspect of ordering radiological imaging studies responsibly. It is especially true for the pediatric practitioner because children are more vulnerable to the biological effects of radiation, such as radiosensitivity, longer lifetime years, and higher cellular mitotic activity. The use of fluoroscopy and computed tomography is commonplace in the practice of craniofacial surgery, but often dose reports from varied investigations are not directly comparable, and the risk of patient harm from the investigation is unclear. This article presents the fundamentals of radiation, dose, and risk as it applies to radiological imaging and also introduces our low dose craniofacial computed tomography protocol.

3D-Printed Models of Cleft Lip and Palate for Surgical Training and Patient Education:

Background: Sculpted physical models and castings of the anatomy of cleft lip and palate are used for parent, patient, and trainee education of cleft lip and palate conditions. In this study, we designed a suite of digital 3-dimensional (3D) models of cleft lip and palate anatomy with additive manufacturing techniques for patient education. Methods: CT scans of subjects with isolated cleft palate, unilateral and bilateral cleft lip and palate, and a control were obtained. Soft tissue and bony structures were segmented and reconstructed into digital 3D models. The oral soft tissues overlying the cleft palate were manually molded with silicone putty and scanned using CT to create digital 3D models. These were then combined with the original model to integrate with segmentable soft tissues. Bone and soft tissues were 3D printed in different materials to mimic the rigidity/softness of the relevant anatomy. These models were presented to the parents/patients at our craniofacial clinic. Visual analog scale (VAS) surveys were obtained pertaining to the particular use of the models, to ascertain their value in parental education. Results: A total of 30 parents of children with cleft conditions completed VAS evaluations. The models provided the parents with a better understanding of their child’s condition with an overall evaluation score of 9.35 ± 0.5. Conclusions: We introduce a suite of 3D-printed models of cleft conditions that has a useful role in patient, parental, and allied health education with highly positive feedback.

Digital Images in Academic Plastic Surgery: A Novel and Secure Methodology for Use in Clinical Practice and Research

Background: Digital photographs have become an integral part in plastic and reconstructive surgery. They are significant in clinical research and outcome evaluation. There is a need for effective and secure methods to store, search, and retrieve those photographs. We developed a Health Insurance Portability and Accountability Act compliant searchable database to archive and index clinical information for clinical and research purposes. Methods: At our craniofacial clinic, digital media (2-D, 3-D, and 4-D photographs) are obtained on a regular basis to evaluate and document treatment outcomes. In addition, patients are asked to enroll in our institutional review board (IRB)-approved imaging database. Daily, we link all digital photographs to the patient encounter through EPIC’s Media Manager. This allows us to automatically identify and extract new digital media, patient demographics, diagnosis codes, relevant providers, and the text of the clinic notes to our digital database. To search our extensive database, we employed the VIEW search engine. Results: To date, our database contains more than 277 000 images of 11 000 patients where more than 1900 patients are enrolled in the IRB study. This search engine allows full-text search with query response time between 2 and 5 seconds. The search engine displays the returned through a web page interface, which includes image thumbnails and the relevant part of the clinic note. In addition, a patient-specific chart allows the user to examine all patient notes and photographs. Conclusion: Our solution allows providers and researchers to retrieve all digital media securely and efficiently.

Three-Dimensional Printing for Craniofacial Surgery: A Single Institution’s 5-Year Experience

Background: As 3-dimensional (3D) printers and models become more widely available and increasingly affordable, surgeons may consider investing in a printer for their own cleft or craniofacial center. To inform surgeons considering adoption of this evolving technology, this study describes one multi-surgeon center’s 5-year experience using a 3D printer. Methods: This study included 3D models printed between October 2012 and October 2017. A 3D Systems ZPrinter 650 was used to create all models. Models were subclassified by type (craniofacial vs noncraniofacial) and diagnosis, and the cost of consumable materials was recorded. A survey was distributed to craniofacial team members who used the printed models. Likert scales and free texts were used for responses about lessons learned and the usefulness of the printer for different craniofacial indications. Results: A total of 106 models were printed at this institution during the 5-year time period. Printing times were 7.4 ± 1.9 hours for complete skulls and 6.0 ± 1.7 hours for maxillofacial prints. The average cost for a complete skull was about US

Comparison of an unsupervised machine learning algorithm and surgeon diagnosis in the clinical differentiation of metopic craniosynostosis and benign metopic ridge

60 in material cost alone. The 3D printer was most frequently used for complex craniosynostosis, hemifacial microsomia syndrome, and fibrous dysplasia cases. The surgeons found the printer to be most useful for planning complex facial orthognathic cases and least useful for routine single-suture synostosis. Conclusion: Three-dimensional printing was found to be helpful for all 4 craniofacial surgeons, who would all invest again in a 3D printer. For lower volume centers, commercially printed models may be a more cost-effective alternative.

Improving the Accuracy of Automated Cleft Speech Evaluation

Metopic suture closure can manifest as a benign metopic ridge (BMR), a variant of normal, to “true” metopic craniosynostosis (MCS), which is associated with severe trigonocephaly. Currently, there is no gold standard for how much associated orbitofrontal dysmorphology should trigger surgical intervention. In our study, we used three-dimensional (3D) curvature analysis to separate the phenotypes along the spectrum, and to compare surgeons’ thresholds for operation. Three-dimensional curvature analyses on 43 subject patients revealed that the mean curvature of mid-forehead vertical ridge was higher for patients who underwent operation than those who did not undergo operation by 1.3 m−1 (p < 0.0001). In addition, these patients had more retruded supraorbital areas by −16.1 m−1 (p < 0.0001). K-means clustering classified patients into two different severity groups, and with the exception of 2 patients, the algorithm’s classification of deformity completely agreed with the surgeons’ decisions to offer either conservative or operative therapy (i.e. 96% agreement). The described methods are effective in classifying severity of deformity and in our experience closely approximate surgeon therapeutic decision making. These methods offer the possibility to consistently determine when surgical intervention may be beneficial and to avoid unnecessary surgeries on children with benign metopic ridge and associated minimal orbitofrontal deformity.

Low-Grade Fibromyxoid Sarcoma With Striking Zonation

An automated cleft speech evaluator, available globally, has the potential to dramatically improve quality of life for children born with a cleft palate, as well as eliminating bias for outcome collaboration between cleft centers in the developed world. Our automated cleft speech evaluator interprets resonance and articulatory cleft speech errors to distinguish between normal speech, velopharyngeal dysfunction and articulatory speech errors. This article describes a significant update in the efficiency of our evaluator. Speech samples from our Craniofacial Team clinic were recorded and rated independently by two experienced speech pathologists: 60 patients were used to train the evaluator, and the evaluator was tested on the 13 subsequent patients. All sounds from 6 of the CAPS-A-AM sentences were used to train the system. The inter-speech pathologist agreement rate was 79%. Our cleft speech evaluator achieved 85% agreement with the combined speech pathologist rating, compared with 65% agreement using the previous training model. This automated cleft speech evaluator demonstrates good accuracy despite low training numbers. We anticipate that as the training samples increase, the accuracy will match human listeners.