Transfacial Two-pin External Mandibular Distraction Osteogenesis: A Technique for Neonatal Airway Obstruction from Robin Sequence.

Surgical management in those with moderate-to-severe airway obstruction includes tongue-lip adhesion, tracheostomy, and/or mandibular distraction osteogenesis. This article describes a transfacial two-pin external device technique for mandibular distraction osteogenesis, utilizing minimal dissection. Methods: The first percutaneous pin is transcutaneously placed just inferior to the sigmoid notch parallel to the interpupillary line. The pin is then advanced through the pterygoid musculature at the base of the pterygoid plates, toward the contralateral ramus, and exits the skin. A second parallel pin is placed spanning the bilateral mandibular parasymphysis distal to the region of the future canine. With the pins in place, bilateral high ramus transverse corticotomies are performed. Using univector distractor devices, the length of activation varies, with the goal of overdistraction to achieve a class III relationship of the alveolar ridges. Consolidation is limited to a 1:1 period with the activation phase, and removal is performed by cutting and pulling the pins out of the face. Results: To guide optimal transcutaneous pin placement, transfacial pins were then placed through twenty segmented mandibles. Mean upper pin (UP) distance was 20.7 ± 1.1 mm from the tragus. The distance between the cutaneous entry of the UP and lower pin was 23.5 ± 0.9 mm, and the tragion-UP-lower pin angle was 118.7 ± 2.9°. Conclusions: The two-pin technique has potential advantages regarding nerve injury and mandibular growth, given an intraoral approach with limited dissection. It may safely be performed on neonates whose small size may preclude the use of internal distractor devices.

Safety of Mandibular Osteotomies in Infants with Pierre Robin Sequence: Computer-Aided Modeling to Characterize the Risks of Various Techniques.

BACKGROUND: Mandibular distraction osteogenesis is effective for the correction of severe tongue-based airway obstruction in infants with Pierre Robin sequence. Involved osteotomies may damage developing tooth buds and/or the inferior alveolar nerve. The authors evaluated the theoretical safety of various osteotomy techniques to better define infantile mandibular anatomy using computer-aided modeling. METHODS: Seven mandibular osteotomy techniques (oblique, inverted-L, multiangular, walking stick, high oblique, vertical/high inverted-L, and horizontal) were simulated using computed tomography studies from infants with Pierre Robin sequence and without other associated conditions. Software was used to manually segment the mandibular bone, inferior alveolar nerve, and tooth buds. RESULTS: Sixty-five computed tomography scans were included, yielding 130 hemimandibles. The horizontal osteotomy pattern had significantly lower theoretical risk of tooth bud (p < 0.001) and inferior alveolar nerve involvement (p < 0.001) than all other patterns. Osteotomies with high vertical components (i.e., vertical, walking stick, and multiangular) had lower theoretical tooth bud involvement than the more proximal oblique and inverted-L osteotomies (p < 0.001). Average lingula location was measured at a point 65 percent of the mandibular width from anterior mandibular border and 63 percent of the mandibular height from the inferior mandibular border. CONCLUSIONS: Surgical planning with computed tomography scans can help evaluate an infant's mandibular anatomy to select an osteotomy that reduces morbidity risks. Regardless of technique, tooth buds and the inferior alveolar nerve are often included in osteotomies. The lingula location in this study demonstrates a position more superior and posterior than that previously described. CLINICAL QUESTION/LEVEL OF EVIDENCE: Therapeutic, V.

Spring-Assisted Surgery for Treatment of Sagittal Craniosynostosis.

ABSTRACT: Craniosynostosis (CSS), the premature fusion of calvarial sutures, most commonly involves the sagittal suture. Cranial vault remodeling (CVR) is a traditional method of CSS correction. Minimally invasive methods are becoming widely accepted, including spring-assisted surgery (SAS). The equipment required for SAS is minimal therefore adaptable to resource challenged health systems. This paper outlines the experience of SAS in Moldova.A retrospective study was performed for patients treated with SAS for sagittal CSS from 2011 to 2018 in Moldova. Perioperative data were recorded including age, length of surgery, blood loss, volume transfused and length of stay. Four patients had pre- and post-operative computed tomography (CT) scans which were used to calculate changes in cephalic index, normative cephalic index, and intracranial volume.Thirteen patients underwent SAS. Diagnoses were made clinically and confirmed with CT. Mean age at surgery was 4.0 months, and length of surgery 62.7 minutes. All but one patient received a blood transfusion, as is standard of practice in Moldova. The mean length of post-operative recovery in ICU was 30.9 hours. No complications required surgical revision. Springs were removed after 4 to 5 months. All patients had a subjective improvement in scaphocephaly. Based on the available CT scans, an increase in cephalic index (7.3%), normative cephalic index (11.8%), and intracranial volume (38.1%) was observed. One patient underwent SAS at 11 months and required cranioplasty for asymmetry at the time of spring removal.SAS is a safe and cost-effective method of CSS correction that can be utilized in countries with limited health system resources.

Cost Analysis for In-house versus Industry-printed Skull Models for Acute Midfacial Fractures.

Industry-printed (IP) 3-dimensional (3D) models are commonly used for secondary midfacial reconstructive cases but not for acute cases due to their high cost and long turnaround time. We have begun using in-house (IH) printed models for complex unilateral midface trauma. We hypothesized that IH models would decrease cost and turnaround time, compared with IP models. METHODS: We retrospectively examined cost and turnaround time data from midface trauma cases performed in 2017-2019 using 3D models (total, n = 15; IH, n = 10; IP, n = 5). Data for IH models were obtained through itemized cost reports from our Biomedical Engineering Department, where the models were printed. Data associated with IP models were obtained through itemized cost reports from our industry vendor. Perioperative data were collected from electronic medical records. RESULTS: The average cost for IH models ($236.38 ± 26.17) was significantly less (P < 0.001) than that for IP models ($1677.82 ± 488.43). Minimal possible time from planning to model delivery was determined. IH models could be produced in as little as 4.65 hours, whereas the IP models required a minimum of 5 days (120 hours) from order placement. There were no significant differences in average operating room time (P = 0.34), surgical complications, or subjective outcomes, but there was a significant difference in estimated blood loss (P = 0.04). CONCLUSION: Utilization of IH 3D skull models is a creative and practical adjunct to complex unilateral midfacial trauma that also reduces cost and turnaround time compared with IP 3D models.

Long-Term Outcomes of Spring-Assisted Surgery for Sagittal Craniosynostosis.

BACKGROUND: Spring-assisted surgery is an accepted alternative to cranial vault remodeling for treatment of sagittal craniosynostosis. The long-term safety and efficacy profiles of spring-assisted surgery have not been established. METHODS: This study is a retrospective examination of all patients treated with spring-assisted surgery (n = 175) or cranial vault remodeling (n = 50) for sagittal craniosynostosis at the authors' institution from 2003 to 2017. Data collected included demographic and operative parameters, preoperative and postoperative Cephalic Indices, and complications. Whitaker grades were assigned blindly by a craniofacial surgeon not involved in patients' care. RESULTS: The mean age at surgery was significantly lower for the spring-assisted surgery group compared with the cranial vault remodeling group (4.6 months versus 22.2 months; p < 0.001). Even when combining spring placement with spring removal operations, total surgical time (71.1 minutes versus 173.5 minutes), blood loss (25.0 ml versus 111.2 ml), and hospital stays (41.5 hours versus 90.0 hours) were significantly lower for the spring-assisted surgery cohort versus the cranial vault remodeling group (p < 0.001 for all). There were no differences in infection, reoperation rate, or headaches between the groups. The percentage improvement in Cephalic Index was not significantly different at 1 (p = 0.13), 2 (p = 0.99), and 6 (p = 0.86) years postoperatively. At 12 years postoperatively, the spring-assisted surgery group had persistently improved Cephalic Index (75.7 preoperatively versus 70.7 preoperatively). Those undergoing spring-assisted surgery had significantly better Whitaker scores, indicating less need for revision surgery, compared with the cranial vault remodeling group (p = 0.006). CONCLUSION: Compared with the authors' cranial vault remodeling technique, spring-assisted surgery requires less operating room time and is associated with less blood loss, but it has equivalent long-term Cephalic Indices and subjectively better shape outcomes. CLINICAL QUESTION/LEVEL OF EVIDENCE: Therapeutic, III.