3D printing in oral and maxillofacial surgery: a nationwide survey among university and non-university hospitals and private practices in Germany.

OBJECTIVES: Oral and maxillofacial surgery (OMFS) has undergone pioneering progress through the development of three-dimensional (3D) printing technologies. The aim of this study was to evaluate the use of 3D printing at OMFS university and non-university hospitals and private practices in Germany. MATERIALS AND METHODS: For explorative assessment, a dynamic online questionnaire containing 10-22 questions about the current use of 3D printing and the reasons behind it was sent to OMFS university and non-university hospitals and private practices in Germany by the study group from the German Association of Oral and Maxillofacial Surgery (DGMKG). RESULTS: In total, 156 participants responded from university (23 [14.7%]) and non-university hospitals (19 [12.2%]) and private practices without (85 [50.5%]) and with 29 (18.6%) inpatient treatment facility. Highest applications of 3D printing were in implantology (57%), microvascular bone reconstructions (25.6%), and orthognathics (21.1%). Among the participants, 37.8% reportedly were not using 3D printing. Among the hospitals and private practices, 21.1% had their own 3D printer, and 2.5% shared it with other departments. The major reason for not having a 3D printer was poor cost efficiency (37.6%). Possessing a 3D printer was motivated by independence from external providers (91.3%) and rapid template production (82.6%). The preferred printing methods were stereolithography (69.4 %) and filament printing (44.4%). CONCLUSIONS: OMFS 3D printing is established in Germany with a wide range of applications. CLINICAL RELEVANCE: The prevalence of 3D printing in hospitals and private practices is moderate. This may be enhanced by future innovations including improved cost efficiency.

Continuous Multidisciplinary Care for Patients With Orofacial Clefts-Should the Follow-up Interval Depend on the Cleft Entity?

OBJECTIVE: The multidisciplinary follow-up of patients with cleft lip with or without palate (CL/P) is organized differently in specialized centers worldwide. The aim of this study was to evaluate the different treatment needs of patients with different manifestations of CL/P and to potentially adapt the frequency and timing of checkup examinations accordingly. DESIGN: We retrospectively analyzed the data of all patients attending the CL/P consultation hour at a tertiary care center between June 2005 and August 2020 (n = 1126). We defined 3 groups of cleft entities: (1) isolated clefts of lip or lip and alveolus (CL/A), (2) isolated clefts of the hard and/or soft palate, and (3) complete clefts of lip, alveolus and palate (CLP). Timing and type of therapy recommendations given by the specialists of different disciplines were analyzed for statistical differences. RESULTS: Patients with CLP made up the largest group (n = 537), followed by patients with cleft of the soft palate (n = 371) and CL ± A (n = 218). There were significant differences between the groups with regard to type and frequency of treatment recommendations. A therapy was recommended in a high proportion of examinations in all groups at all ages. CONCLUSION: Although there are differences between cleft entities, the treatment need of patients with orofacial clefts is generally high during the growth period. Patients with CL/A showed a similarly high treatment demand and should be monitored closely. A close follow-up for patients with diagnosis of CL/P is crucial and measures should be taken to increase participation in follow-up appointments.

"Black bone": the new backbone in CAD/CAM-assisted craniosynostosis surgery?

BACKGROUND: Computer-assisted design and manufacturing (CAD/CAM) techniques have been implemented in craniosynostosis surgery to facilitate cranial remodeling. However, until now, computed tomography (CT) scans with ionizing radiation were necessary to plan the procedure and create guiding templates. The purpose of this study was to present our series using CAD/CAM techniques in planning and conducting fronto-orbital advancement surgery in patients with trigonocephaly with datasets acquired only by "black bone" magnetic resonance imaging (MRI). METHODS: Six consecutively operated cases from 2019 were included in this study. All patients suffered from non-syndromic trigonocephaly with no primary surgeries. All patients underwent cranial MRI including black bone sequences. Preoperative planning and guides were created based on the DICOM datasets. We analyzed demographic data, clinical data, and outcome measured by Whitaker score. RESULTS: In all cases, precise frontobasal advancement was possible with the CAD/CAM guides created by black bone MRI. The mean operation time and planning time were 222 and 32 min. The time on intensive and intermediate care unit (ICU/IMC) time was 4.5 days, respectively. All but one case were classified as Whitaker I. CONCLUSION: In trigonocephaly treatment by frontobasal advancement, black bone MRI-based CAD/CAM craniosynostosis surgery is safe and feasible. It offers the major advantage of completely avoiding CT scans and ionizing radiation with superior imaging quality of intracranial structures. Thus, it improves intraoperative safety and-at the same time-has the potential to reduce operating room (OR) time.

Improved access in minimally invasive temporomandibular joint surgery through a novel endaural template.

BACKGROUND: Digitally designed surgical templates for minimally invasive temporomandibular joint (TMJ) surgery (MITMJS) are a promising tool for improving the safety of these procedures. Given the TMJ anatomy, the template fitting and intraoperative overview are the most important issues for a safe surgery. This article is a technical advance article that aims to describe an endaural surgical template based on the Moses approach as a possible solution in TMJ surgery. METHODS: Three patients with internal derangement were treated with the guidance of a MITMJS template based on cone beam computed tomography (CBCT) and a surface imprint of the periauricular region. None of the patients needed an additional open surgical procedure. Fitting of the templates was judged in terms of position and rotational stability. Surgical side effects and complications were recorded for each patient. RESULTS: The template design and clinical use were satisfactory for MITMJS. The templates showed satisfying fit and good visibility. In the study cohort, no bleeding, facial nerve injury, or other complications occurred after the procedure, and no visible scars were noted postoperatively. CONCLUSION: Our feasibility report on template-guided MITMJS shows a promising new application of templates. It points to improved access in arthroscopy or arthrocentesis of TMJ surgery through endaural access with an increased level of safety during surgery.

How is neck dissection performed in Oral and Maxillofacial Surgery? Results of a representative nationwide survey among university and non-university hospitals in Germany.

INTRODUCTION: Neck dissection (ND) is a surgical procedure addressing cervical lymph nodes and metastases in patients with oral squamous cell carcinoma (OSCC). The aim of this study was to analyze clinical decisions regarding indications and variations of ND in Oral and Maxillofacial Surgery (OMFS) in Germany. MATERIAL AND METHODS: A nationwide survey of the German Association of Oral and Maxillofacial Surgery was performed using dynamic online questionnaires including 38 questions. Data about oncological centers, case numbers, and staging procedures were collected. Relevant aspects, such as inclusion of level IIb and levels IV and V to ND, uni- vs. bilateral ND, and the influence of extra-nodal extension (ENE) of metastases on extension of ND were evaluated. RESULTS: Eighty-four OMFS of university and non-university hospitals participated in the study (responding rate 21.4%). Sixty-six (78.57%) stated to work at certified cancer centers and 53.57% of the hospitals treated between 50 and 100 OSCC cases per year. CT and/or MRI of the head and neck was performed in most of the staging procedures. Level IIb was included by 71 (93.42%) of the participants in selective ND. Levels IV and V were included by 53 (69.74%) in node-positive neck. In solitary ipsilateral metastases (ENE-), 49 participants (62.82%) stated to perform exclusively an ipsilateral ND and 40 (51.95%) stated to perform only an ipsilateral ND in ENE+. CONCLUSION: This study demonstrated a high rate of certified cancer centers in Germany showing differences regarding staging procedures, indications, and extension of ND, especially in increasingly complex cases. CLINICAL RELEVANCE: Clinical decisions regarding ND are dependent on case-individual aspects and must be decided individually.

Impact of COVID-19 on Oral and Maxillofacial Surgery: Preliminary Results After the Curfew.

INTRODUCTION: The COVID-19 pandemic affects basic health care in maxillofacial surgery (MFS) due to the shift in resources and the change in patient disorders treated during the pandemic. This paper aims to elucidate the medical and financial consequences driven by the measures for COVID-19 treatment in a tertiary care centre. MATERIAL AND METHODS: To evaluate the impact of pandemic measures on daily routines of MFS, the surgical schedule during the first 2 weeks after the onset of the curfew (March 2020), and to compare it with the schedule of the same period of time 1 year earlier. Furthermore, postponed surgeries as well as cancelled follow-ups are listed. The loss of earning was calculated as well as the number and kind of postponed procedures. RESULTS: The number of surgeries decreased by 45% (n = 163 in 2019 vs n = 89 in 2020), and the duration of the surgeries decreased from 94.2 minutes to 62.1 minutes. No elective surgeries, such as implantology, aesthetic surgery, or orthognathic surgery, took place. Furthermore, also trauma cases decreased from 9 to 3 cases. Considering all variables, the financial loss can be calculated as approximately 100,256.50 Euros per week. CONCLUSION: The impact of COVID-19 on MFS is certainly of medical and economic importance and is related to the duration of the pandemic.

Osteogenic Potential of Mesenchymal Stem Cells from Adipose Tissue, Bone Marrow and Hair Follicle Outer Root Sheath in a 3D Crosslinked Gelatin-Based Hydrogel.

Bone transplantation is regarded as the preferred therapy to treat a variety of bone defects. Autologous bone tissue is often lacking at the source, and the mesenchymal stem cells (MSCs) responsible for bone repair mechanisms are extracted by invasive procedures. This study explores the potential of autologous mesenchymal stem cells derived from the hair follicle outer root sheath (MSCORS). We demonstrated that MSCORS have a remarkable capacity to differentiate in vitro towards the osteogenic lineage. Indeed, when combined with a novel gelatin-based hydrogel called Osteogel, they provided additional osteoinductive cues in vitro that may pave the way for future application in bone regeneration. MSCORS were also compared to MSCs from adipose tissue (ADMSC) and bone marrow (BMMSC) in a 3D Osteogel model. We analyzed gel plasticity, cell phenotype, cell viability, and differentiation capacity towards the osteogenic lineage by measuring alkaline phosphatase (ALP) activity, calcium deposition, and specific gene expression. The novel injectable hydrogel filled an irregularly shaped lesion in a porcine wound model displaying high plasticity. MSCORS in Osteogel showed a higher osteo-commitment in terms of calcium deposition and expression dynamics of OCN, BMP2, and PPARG when compared to ADMSC and BMMSC, whilst displaying comparable cell viability and ALP activity. In conclusion, autologous MSCORS combined with our novel gelatin-based hydrogel displayed a high capacity for differentiation towards the osteogenic lineage and are acquired by non-invasive procedures, therefore qualifying as a suitable and expandable novel approach in the field of bone regeneration therapy.

Mixed reality in oral and maxillofacial surgery: a symbiosis of virtual and augmented reality or a pointless technological gadget?

INTRODUCTION: Mixed reality (MR) represents a new evolution in technological development that combines both virtual reality (VR) and augmented reality (AR) to create a blend of the physical and digital worlds. However, the potential role of MR in preoperative diagnostics in oral and maxillofacial surgery has not been scientifically investigated and remains generally unclear. This article presents a workflow that integrated MR in its scheme. It also evaluates the potential benefit of MR compared with its predecessors, VR and AR. MATERIAL AND METHODS: MR technology was used to plan the surgical treatment of a clinical case with an extensive tumor of the left maxilla. A workflow proposal incorporating both the surgeon and radiation oncologist is presented based on this experience. A total of 10 examiners rated the usability and applicability of MR for daily routines. RESULTS: MR showed good results during preoperative planning for a surgically extensive case in terms of displaying 3D structures and enhancing the physical and virtual interactions among the examiners. Previously described drawbacks of other VR/AR applications such as nausea and motion sickness were not observed with MR. However, MR seems to lack intraoperative usability, which is a drawback. CONCLUSION: MR shows great potential in improving the preoperative assessment of 3D DICOM datasets and thus facilitating diagnostic measures. However, further improvements should be made to implement an MR workflow and incorporate it into the clinical treatment planning tree.

Ankle Brachial Index Predicts for Difficulties in Performing Microvascular Anastomosis.

PURPOSE: In reconstructive microsurgery, severe arteriosclerosis is a known predictor for free flap failure because of problems with the vascular anastomosis. We investigated whether the ankle brachial index (ABI) could be a suitable preoperative measurement for the prediction of compromise regarding vascular anastomosis in patients undergoing microsurgical reconstruction. MATERIAL AND METHODS: We conducted a prospective cohort study of patients who had undergone reconstructive microvascular surgery in a tertiary care center from 2015 to 2017. The ABI was preoperatively assessed by dividing the systolic blood pressure measured at the ankle by the brachial systolic blood pressure. Results from 0.9 to 1.3 are within the physiologic range. Values less than 0.9 indicate moderate to severe arteriosclerosis, and those greater than 1.3 indicate the major form of arteriosclerosis with complete calcification of the tunica media. The ABI value correlated with the ease of the anastomosis (rated from 1 [very straightforward] through 5 [very difficult]), gross examination findings (intraluminal plaque [yes vs no]), and the necessity of plaque removal before anastomosis (yes vs no). In addition, cross-sectional specimens were obtained from the arteries and veins of the donor and recipient sites intraoperatively. The specimens were rated histologically for the arteries and veins using an ordinal scale. Histologic evaluation was performed to confirm and objectify the results from the ABI. Statistical analysis was performed using SPSS software, version 24.0 (IBM Corp, Armonk, NY) and t tests, analysis of variance, and χ2 tests. RESULTS: The sample included 41 patients with a mean age of 56.7 years; 59% were men. The mean ABI was 1.06. The mean ease of anastomosis was 1.8. The mean ABI was associated with the ease of anastomosis. A pathologic ABI was significantly related to problems with the arterial anastomosis (P = .004) and increased arteriosclerosis in the arteries from the donor (P = .047) and recipient (P = .036) sites. CONCLUSIONS: A pathologic ABI was associated with increased difficulty with the microvascular anastomosis.

Objective computerised assessment of residual ridge resorption in the human maxilla and maxillary sinus pneumatisation.

OBJECTIVES: Atrophic resorption of the maxillary alveolar ridge is a complication that makes implantological rehabilitation critical. Our aim was to develop a novel computer aided procedure for the accurate quantitative assessment of maxillary residual ridge resorption including pneumatisation of the maxillary sinus that goes beyond previously described approaches and to apply it to a large dataset. MATERIALS AND METHODS: To develop and refine the method, we performed a retrospective analysis using computed tomography data from 405 patients to generate segmented, three-dimensional models of zygomaticomaxillary bones and maxillary sinuses. Using anatomical landmarks and orientation lines or planes, all models were aligned automatically to subsequently generate cross-sectional images (n = 2835), enabling the classification of atrophy as well as the quantification of volumes and caudal extensions of the maxillary sinuses. RESULTS: We developed and implemented an accurate and reproducible workflow for the semi-automated analysis of volumetric maxillary images. Comprehensive statistical analysis of the large quantitative dataset revealed various correlations of maxillary process heights and sinus volumes with atrophy class, age and region and identified conjectural trends over the patient group. CONCLUSIONS: The method was used successfully to process a large dataset to classify atrophy, to measure alveolar height parameters, and to quantify maxillary sinus volume, bottom volume and pneumatisation. CLINICAL RELEVANCE: Apart from the anthropometric value of the generated dataset, the method could be applied to provide additional and more accurate data to assess the necessity of bone augmentation in the context of three-dimensional planning before implantation.

Flow Chart for Reconstructive Head and Neck Surgery in Composite Soft and Hard Tissue Defects.

INTRODUCTION: Virtual planning of reconstructive surgical procedures in patients with osseous and composite defects in the head and neck region is becoming increasingly a state of the art modality. However, computational algorithms lack the capability of planning the involved soft tissue and vascular pedicle position. The authors present a flow-chart to solve this problem in the reconstruction of defects of the upper and lower jaw. MATERIAL AND METHODS: Clinical records from 2013 to 2018 from a tertiary care center were screened for patients undergoing osseous reconstruction in the head and neck region. A flow-chart considering soft tissue positioning and the anatomical course of the vascular pedicle was assessed in consideration of the defect and donor-site. RESULTS: A total of 81 osseous and composite microvascular reconstructive procedures have been conducted. Defects of the lower jaw were the most common (n = 61). The free fibula flap was the most common reconstructive measure and showed a wide versatility of surgical options to reconstruct these defects. The flow charts were assessed accordingly in these procedures. CONCLUSION: Soft tissue and vascular pedicle positioning can be planned pre-operatively by the use of virtual planning and should be considered as an enhancement tool to the already existing computational algorithms of planning hard tissue reconstruction.

Hand Perfusion in Patients with Physiological or Pathological Allen's Tests.

BACKGROUND: The Allen test (AT) is a widely used clinical tool for the preoperative assessment of sufficient dual vessel hand perfusion although the impact of a pathological AT on tissue perfusion of the hand is not entirely clear. This study reveals perfusion changes of the hand in patients with pathological and physiological AT after terminating the dual blood supply. METHODS: Patients were distributed into 2 groups (physiological and pathological AT) that each contained 25 members. Perfusion of the thumb, middle, and small fingers was measured with a laser Doppler based ("oxygen-to-see" [O2C]) device. A steady state was measured and also values at 1, 3, 5, and 10 minutes after radial occlusion were measured. RESULTS: In patients with a physiological AT, only 1 out of 18 values differed significantly from the steady state measurements after 10 minutes, whereas patients with a pathological AT showed significant alterations in 8 out of 18 values. Oxygen saturation of the superficial and deep tissues appeared to be significantly worse in patients with a pathological AT. CONCLUSION: Patients with a pathological AT suffered significantly more from the loss of dual hand perfusion than patients with a physiological AT. Patients with a pathological AT need more time to compensate for the altered perfusion pattern.

Influence of a strictly perioperative antibiotic prophylaxis vs a prolonged postoperative prophylaxis on surgical site infections in maxillofacial surgery.

PURPOSE: The adequate perioperative antibiotic prophylaxis in maxillofacial surgery is still under discussion due to the wide range of hard and soft tissue procedures as well as contaminated, semi-contaminated and clean surgical sides. Perioperative antibiosis is an easy applicable tool that can be used to decrease nosocomial morbidity and mortality by reducing the rate of infections. We compared strictly perioperative antibiosis with an extended postoperative prophylactic antibiosis. MATERIALS AND METHODS: In this study, 901 consecutive patients, from a tertiary care maxillofacial surgery department were included and distributed into two groups: The first group received peri- and postoperative antibiotic prophylaxis (PP; n = 365) from the day of operation until the fifth day postoperatively. The second group was treated with single shot prophylaxis with intraoperative repetition as needed (SSP; n = 536) only. Furthermore, the patients were grouped according to their main diagnosis and surgical procedure. For comparison, general anamnestic data, cultured bacteria and resistances, number of surgical site infections and duration of hospitalization were compared. RESULTS: There were no statistically significant differences in general diseases or extent of surgery between the groups. There was no statistical difference in the surgical site infections between the groups regardless of their diagnosis. There were significant correlations between tracheotomised patients (p < 0.001) as well as patients with a higher BMI (p = 0.009) and the incidence of surgical site infections. Most common cultured bacteria were staphylococci. CONCLUSION: Based on the findings of the study, we believe that a perioperative antibiosis delivers a sufficient prophylaxis for patients undergoing maxillofacial surgery procedures.

Role of Swallowing Function of Tracheotomised Patients in Major Head and Neck Cancer Surgery.

INTRODUCTION: Tracheotomy is a frequent procedure in extended head and neck cancer surgery and known to be a risk factor for prolonged hospitalization. The authors hypothesized that the clinical course and delayed decannulation of patients are not only influenced by airway narrowing, but also by a compromised postoperative swallowing function. MATERIAL AND METHODS: The investigators implemented a retrospective cohort study. The sample was composed of a tertiary care center patients who underwent major head and neck cancer surgery, each receiving a tracheostomy. Data collected include general clinical data as well as endoscopical evaluation of swallowing function and aspiration rate. Descriptive and bivariate statistics were computed and the P value was set at.05. RESULTS: The sample was composed of 96 patients with an average age of 64.2 and sex ratio of 1.4:1 (m:f). There was a strong statistically significant relation between swallowing function and timing of decannulation (P < 0.001) and duration of hospitalization (P < 0.001). Age (P = 0.55), sex (P = 0.54), tumor size (P = 0.12), general diseases (P = 0.24), distant metastases (P = 0.15), or extent of neck dissection (P = 0.15) were not significantly associated to swallowing function. Permanent cannulation was significantly correlated to a primary cancer of the soft palate or base of the tonge (P < 0.001). CONCLUSION: The results of this study confirm the importance of the evaluation of swallowing function before the removal of the tracheotomy cannula in head and neck cancer patients.

Comparison of Bone Grafts From Various Donor Sites in Human Bone Specimens.

The objective of the current study was to compare the three-dimensional (3D) morphometric microstructure in human cadaveric bone specimens taken from various commonly utilized donor sites for autogenous bone grafting. Autogenous bone grafts can be harvested from various anatomic sites and express heterogeneous bone quality with a specific 3D microstructure for each site. The long-term structural integrity and susceptibility to resorption of the graft depend on the selected donor bone. Micro-computed tomography generates high-resolution datasets of bone structures and calcifications making this modality versatile for microarchitecture analysis and quantification of the bone. Six bone specimens, 10 mm in length, where anatomically possible, were obtained from various anatomical sites from 10 human dentate cadavers (4 men, 6 women, mean age 69.5 years). Specimens were scanned using a micro-computed tomography device and volumetrically reconstructed. A virtual cylindrical inclusion was reconstructed to analyze the bone mineral density and structural morphometric analysis using bone indices: relative bone volume, surface density, trabecular thicknesses, and trabecular separation. Calvarial bone specimens showed the highest mineral density, followed by the chin, then mandibular ramus then the tibia, whereas iliac crest and maxillary tuberosity had lower bone mineral densities. The pairwise comparison revealed statistically significant differences in the bone mineral density and relative bone volume index in the calvaria, mandibular ramus, mandibular symphysis groups when compared with those in the iliac crest and maxillary tuberosity, suggesting higher bone quality in the former groups than in the latter; tibial specimens expressed variable results.

Bone regeneration using composite non-demineralized xenogenic dentin with beta-tricalcium phosphate in experimental alveolar cleft repair in a rabbit model.

BACKGROUND: Alveolar cleft repair is performed via bone grafting procedure to restore the dental arch continuity. A suitable bone substitute materials should possess osteoinductive and osteoconductive properties, to promote new bone formation, along with a slowly resorbable scaffold that is subsequently replaced with functionally viable bone. Calcium phosphate biomaterials have long proved their efficacy as bone replacement materials. Dentin in several forms has also demonstrated its possibility to be used as bone graft replacement material in several studies. The purpose of this study was to evaluate bone regeneration pattern and quantify bone formation after grafting pre-established experimental alveolar clefts defects model in rabbits using composite xenogenic dentin and ß-TCP in comparison to ß-TCP alone. METHODS: Unilateral alveolar cleft defects were created in 16 New Zealand rabbits according to previously described methodology. Alveolar clefts were allowed 8 weeks healing period. 8 defects were filled with ß-TCP, whereas 8 defects filled with composite xenogenic dentin with ß-TCP. Bone regeneration of the healed defects was compared at the 8 weeks after intervention. Quantification of bone formation was analyzed using micro-computed tomography (µCT) and histomorphometric analysis. RESULTS: µCT and histomorphometric analysis revealed that defects filled with composite dentin/ß-TCP showed statistically higher bone volume fraction, bone mineral density and percentage residual graft volume when compared to ß-TCP alone. An improved surgical handling of the composite dentin/ß-TCP graft was also noted. CONCLUSIONS: Composite xenogenic dentin/ß-TCP putty expresses enhanced bone regeneration compared to ß-TCP alone in the reconstruction of rabbit alveolar clefts defects.

Color duplex ultrasonography versus handheld Doppler to plan anterior lateral thigh flaps.

BACKGROUND: The anterior lateral thigh flap (ALT) has become increasingly important in reconstructive surgery in the head and neck region. To cope with the problem of anatomical variability in the supplying blood vessels, preoperative evaluation is desirable. Purpose of the study is to compare the most commonly used Doppler devices Handheld Doppler (HD) and Color Doppler Ultrasonography (CDU) for their clinical reliability. METHODS: Forty five consecutive head and neck cancer patients (mean age 66.0 ± 11.2 years) were included in the study. They all underwent a reconstruction via ALT flap for a defect in the head and neck area. Study period ranged from May 2014 to August 2015. We preoperatively conducted HD and CDU on the lateral thigh and compared the intraoperative findings by measuring presence of the perforator and distance to the estimated position. RESULTS: There were 95 perforators identified in 45 patients. The sensitivity and positive predictive value (PPV) were calculated as 97.9% and 100% for CDU and 90.5% and 80.4% for HD, respectively. Accuracy was significantly greater with the HD compared to the CDU device (P < 0.001) and was strongly associated with body mass index (BMI) (P < 0.001). This effect was stronger in HD than in CDU (r = 0.800; P < 0.001 versus r = 0.673; P < 0.001). CONCLUSIONS: Our results indicate CDU is more precise and reliable than HD with respect to detecting the anatomical position of perforating arteries. © 2017 Wiley Periodicals, Inc. Microsurgery 37:388-393, 2017.

Perception of aesthetic features after surgical treatment of craniofacial malformations by observers of the same age: An eye-tracking study.

The aim of this study is to evaluate where exactly children and adolescents of the same group look when they interact with each other, and attempt to record and analyse the data recorded by eye-tracking technology. MATERIALS AND METHODS: 60 subjects participated in the study, evenly divided into three age categories of 20 each in pre-school/primary school age (5-9 years), early adolescence (10-14 years) and late adolescence/transition to adulthood (15-19 years). Age groups were matched and categorized to be used both for creating the picture series and testing. Photographs of patients with both unilateral and bilateral cleft lip and palate were used to create the series of images which consisted of a total of 15 photos, 5 of which were photos of patients with surgically treated cleft deformity and 10 control photos with healthy faces, that were presented in random order. Using the eye-tracking module, the data on "area of first view" (area of initial attention), "area with longest view" (area of sustained attention), "time until view in this area" (time of initial attention) and "frequency of view in each area" (time of sustained attention) were calculated. RESULTS: Across all groups, there was no significant difference for the individual regions for the parameters of initial attention (area of first view), while the time until first fixation of one of the AOIs (time until view in this area) was significant for all facial regions. A predictable path of the facial scan is abandoned when secondary facial deformities are present and attention is focused more on the region of an existing deformity, which are the nose and mouth regions. CONCLUSIONS: There are significant differences in both male and female participants' viewing of faces with and without secondary cleft deformity. While in the age group of the younger test persons it was still the mouth region that received special attention from the male viewers, this shifted in the male test persons of the middle age group to the nose region, which was fixed significantly more often and faster. In the female participants, the mouth and nose regions were each looked at for twice as long compared to the healthy faces, making both the mouth and the nose region are in the focus of observation.

Computer assisted skull base surgery: a contemporary review.

Skull base surgery has evolved significantly since Harvey Cushing's first descriptions in the early 1900s. Computer aided surgery (CAS) applications continue to expand; they include virtual surgical planning, augmented and virtual reality, 3D printing of models/cutting guides/implants, surgical navigation, and intraoperative imaging. The authors will review the current skull base CAS literature and propose a computer aided surgical workflow categorizing these applications into 3 phases: 1) Virtual planning, 2) Surgical execution, 3) Intraoperative verification.