intraoperative-assessment-resection-margins-oral-cavity-cancer-this

Intraoperative Assessment of Resection Margins in Oral Cavity Cancer: This is the Way

The goal of head and neck oncological surgery is complete tumor resection with adequate resection margins while preserving acceptable function and ...

Erasmus MC University Medical Center

Vertical distraction of the alveolar process is an efficient method for augmentation prior to inserting dental implants. In this study, complications of this procedure and relapse of the transport segment were evaluated in partially dentulous patients. Twenty patients underwent distraction by means of extraosseous distractors. The location of the defects was the anterior mandible (4), posterior mandible (4), anterior maxilla (10) and posterior maxilla (2). Bone height was measured on panoramic radiographs preoperatively, after distraction and after implant placement at the mesial and distal point of the implant(s). Mean alveolar distraction was 6.5mm at the mesial point (P<0.001) and 6.1mm at the distal point (P<0.001). The mean relapse at the mesial point was 20% and at the distal point 17% (P<0.05). The intraoperative and postoperative problems encountered were fracture (1) and lingual (4) and palatal (6) displacement of the transport segment. Overall complication rate was 55%. Of all implants placed (n=63) one was lost. Implant success rate was 98%. Distraction seems to be a suitable treatment for vertically deficient alveolar bone, but a relatively high although manageable complication rate must be confronted, including considerable relapse.

Complications and relapse in alveolar distraction osteogenesis in partially dentulous patients.

To investigate the changes of upper airway volume in syndromic craniosynostosis patients following Le Fort III advancement, computed tomographic scans were analyzed and related to the amount of advancement.

Three-dimensional airway changes after Le Fort III advancement in syndromic craniosynostosis patients.

Little is known about the positional change of the Le Fort III segment following advancement. To study this, pre- and postoperative computed tomography scans of 18 craniosynosthosis patients were analyzed. The Le Fort III segment movement was measured by creating a reference coordinate system and by superpositioning the postoperative over the preoperative scan. On both the pre- and postoperative scans, four anatomical landmarks were marked: the most anterior point of the left and right foramen infraorbitale, the nasion, and the anterior nasal spine. A significant anterior movement of the four reference points was observed. No significant transversal differences were found. A significant difference between the anterior movement of the nasion and anterior nasal spine was found. In vertical dimension, there was a significant cranial movement of nasion in the study group. In addition, from all patients standardized lateral X-rays were viewed to determine the location and direction of force application that were linked to the outcomes of the three-dimensional movement of the nasion and anterior nasal spine (ANS) and the surgical technique. Conclusively, a significant advancement of the midface can be achieved with Le Fort III distraction osteogenesis in this specific patient group. Counterclockwise movement seemed to be the most dominant movement despite different modes of anchorage. 

Three-dimensional position changes of the midface following Le Fort III advancement in syndromic craniosynostosis.

To provide an overview of current practice patterns with regard to Robin sequence (RS) patients in Europe, a survey was conducted among European clinicians. This online survey consisted of different sections assessing characteristics of the respondent and clinic, definition, diagnosis, treatment, and follow-up. In total, surveys from 101 different European clinics were included in the analysis, and 56 different RS definitions were returned. The majority (72%) of the respondents used a sleep study system to determine the severity of the airway obstruction. A total of 63% used flexible endoscopy and 16% used rigid endoscopy in the diagnostic process. Treatment of the airway obstruction differed considerably between the different countries. Prone positioning for mild airway obstruction was the treatment modality used most often (63%). When prone positioning was not successful, a nasopharyngeal airway was used (62%). Surgical therapies varied considerably among countries. For severe obstruction, mandibular distraction was performed most frequently. Three-quarters of the respondents noted the presence of catch-up growth in their patient population. This first European survey study on definition and management of RS shows that there are considerable differences within Europe. Therefore, we would encourage the establishment of national (and international) guidelines to optimize RS patient care. 

Robin sequence: A European survey on current practice patterns.

There is widespread lack of consensus regarding treatment of airway obstruction in children with Robin Sequence. This study aimed to systematically summarize outcomes of non-surgical and surgical options to treat airway obstruction in children with Robin Sequence. The authors searched the Medline, EMBASE and CENTRAL databases. Studies primarily on mandibular distraction were excluded. Study quality was appraised with the Methodological Index for Non-Randomized Studies (MINORS) score. Forty-eight studies were included, of which 45 studies had a retrospective non-comparative set up, two studies had a prospective design and one study was a clinical trial. The mean MINORS score was 7.3 (range 3-10). The rates of successful relief of the airway obstruction (SRoAO) were: not available for orthodontic appliance (2 studies, n = 24), 67-100% for nasopharyngeal airway (6 studies, n = 126); 100 % for non-invasive respiratory support (2 studies, n = 12); 70-96% for tongue-lip adhesion (11 studies, n = 277); 50-84% for subperiosteal release of the floor of the mouth (2 studies, n = 47); 100% for mandibular traction (3 studies, n = 133); 100% for tracheostomy (1 study, n = 25). The complication rate ranged from zero to 55%. Although SRoAO rates seemed comparable, high-level evidence remains scarce. Future research should include description of the definition, treatment indication, and objective outcomes.

Non-surgical and surgical interventions for airway obstruction in children with Robin Sequence.

The purpose of our study was to investigate the association of different socioeconomic and sociodemographic factors with dental caries in six-year-old children. Furthermore, we applied a district based approach to explore the distribution of dental caries among districts of low and high socioeconomic position (SEP).

Social inequalities and dental caries in six-year-old children from the Netherlands.

Landmarking of 3D facial surface scans is an important analysis step in medical and biological applications, such as genome-wide association studies (GWAS). Manual landmarking is often employed with considerable cost and rater dependent variability. Landmarking automatically with minimal training is therefore desirable. We apply statistical ensemble methods to improve automated landmarking of 3D facial surface scans. Base landmarking algorithms using features derived from 3D surface scans are combined using either bagging or stacking. A focus is on low training complexity of maximal 40 training samples with template based landmarking algorithms that have proved successful in such applications. Additionally, we use correlations between landmark coordinates by introducing a search strategy guided by principal components (PCs) of training landmarks. We found that bagging has no useful impact, while stacking strongly improves accuracy to an average error of 1.7 mm across all 21 landmarks in this study, a 22% improvement as compared to a previous, comparable algorithm. Heritability estimates in twin pairs also show improvements when using facial distances from landmarks. Ensemble methods allow improvement of automatic, accurate landmarking of 3D facial images with minimal training which is advantageous in large cohort studies for GWAS and when landmarking needs change or data quality varies.

Ensemble landmarking of 3D facial surface scans.

Landmarking of CT scans is an important step in the alignment of skulls that is key in surgery planning, pre-/post-surgery comparisons, and morphometric studies. We present a novel method for automatically locating anatomical landmarks on the surface of cone beam CT-based image models of human skulls using 2D Gabor wavelets and ensemble learning. The algorithm is validated via human inter- and intra-rater comparisons on a set of 39 scans and a skull superimposition experiment with an established surgery planning software (Maxilim). Automatic landmarking results in an accuracy of 1-2 mm for a subset of landmarks around the nose area as compared to a gold standard derived from human raters. These landmarks are located in eye sockets and lower jaw, which is competitive with or surpasses inter-rater variability. The well-performing landmark subsets allow for the automation of skull superimposition in clinical applications. Our approach delivers accurate results, has modest training requirements (training set size of 30-40 items) and is generic, so that landmark sets can be easily expanded or modified to accommodate shifting landmark interests, which are important requirements for the landmarking of larger cohorts.

Automated human skull landmarking with 2D Gabor wavelets.

A retrospective cohort study was initiated to analyse the prevalence, risk factors and treatment modalities of feeding difficulties in patients with craniofacial microsomia. This study included 755 subjects with craniofacial microsomia from three craniofacial centres. Medical charts were reviewed for severity of the deformity, documented feeding difficulties, age at which feeding difficulties first presented and treatment, presence of cleft lip/palate, extracraniofacial anomalies, and obstructive sleep apnoea. In total, 199 patients (26.4%) had documented feeding difficulties. Patients with bilateral involvement, Pruzansky-Kaban III classification, cleft lip/palate, or obstructive sleep apnoea were significantly more at risk for developing feeding difficulties and significantly more often needed additional feeding via a nasogastric tube than patients without these risk factors.

Feeding difficulties in craniofacial microsomia: A multicenter retrospective analysis of 755 patients.

Fracture rate in childhood is increasing and its consequences may affect health and developmental processes and cause school absence and restricted activity days. There are scarce epidemiologic studies regarding fractures in children. The aim of this study was to evaluate if pediatric fractures show disparities across sexes and ethnic groups. This study was conducted based on data from 3632 participants of the Generation R Study. Prevalent fractures were assessed using a questionnaire at a mean age of 9.7 years. Child's ethnicity was determined based on country of birth of the parents using questionnaires (geographic ancestry) or admixture analysis (genetic ancestry). Associations between fracture occurrence and sex or ethnicity were evaluated using logistic regression models adjusted for age, weight, lean mass fraction, bone mineral density (BMD) and sex/ethnicity. Fracture was reported for 525 (14.5%) children. The great majority of these children were classified as European (N = 3164), followed by African (N = 283) and Asian (N = 185) based on geographic ancestry. Similarly, the highest proportion of Europeans was observed based on genetic ancestry. Prevalence of fractures was not different between boys and girls, even after adjustment for possible confounders (OR: 1.03, 95% CI 0.84-1.27, p-value = 0.8). However, odds of prevalent fractures were two times higher in European when compared to Asian children (OR: 2.01, 95% CI 1.17-3.45, p-value = 0.01), and 1.5 times higher when compared to African children (OR: 1.50, 95% CI 1.00-2.26, p-value = 0.05). Overall, in this study, European children showed a highest risk of prevalent fractures independently of factors such as body composition and BMD, while no difference in the prevalence of fractures between boys and girls was observed.

Fractures in school age children in relation to sex and ethnic background: The Generation R Study.

Bone modeling is an important process in the growing skeleton. An inadequate bone modeling in response to mechanical loads would lead some children to develop weaker bones than others. The resulting higher stresses in the bones would render them more susceptible to fracture. We aimed to examine the association between femoral stress (FS) derived from structural parameters and BMD in relation to incident fractures in children. Bone stress was evaluated at the medial femoral neck, a skeletal site subject to large forces during normal locomotion. This study comprises 1840 children from the Generation R Study, with whole body and hip DXA scans at a mean age of 6.01 years. Hip structural analysis (HSA) was used to measure femur geometry for the FS calculation. Data on fractures occurring over the following 4 years after the DXA assessment were obtained by questionnaire. Incident fracture was observed in 7.6% of the participating children. Cox-multivariate regression analysis, described as hazard ratios (HR), showed that after adjustment for sex, ethnicity, age, weight and lean mass fraction, there was a significant increase in the risk of incident fracture for every standard deviation (SD) decrease in total body BMD (HR: 1.35, 95% CI 1.05-1.74, p-value = 0.021), femoral neck BMD (HR: 1.31, 95% CI 1.09-1.58, p-value = 0.005) and narrow neck BMD (HR: 1.39, 95% CI 1.14-1.68, p-value = 0.001). Whereas, every increment of one SD in femoral stress resulted in 1.33 increased risk of incident fractures (HR: 1.33, 95% CI 1.13-1.57, p-value = 0.001). This association remained (borderline) significant after the adjustment for DXA derived BMD measurements. Our results show that increased bone stress may underlie greater susceptibility to traumatic fractures in children (partially independent of BMD) and underscore the utility of hip DXA scans for the assessment of paediatric bone health and specifically fracture risk.

Femoral stress is prominently associated with fracture risk in children: The Generation R Study.

Depth of invasion (DOI) is the most important predictor for lymph node metastasis (LNM) in early stage (T1-T2) oral cancer. The aim of this study is to validate the cut-off value of 4 mm on which the decision to perform an Elective Neck Dissection (END) is made.

Article	Year
Complications and relapse in alveolar distraction osteogenesis in partially dentulous patients. International journal of oral and maxillofacial surgery\| PubMed ID: 17604966	2007
Three-dimensional airway changes after Le Fort III advancement in syndromic craniosynostosis patients. Plastic and reconstructive surgery\| PubMed ID: 20679838	2010
Three-dimensional position changes of the midface following Le Fort III advancement in syndromic craniosynostosis. Journal of cranio-maxillo-facial surgery : official publication of the European Association for Cranio-Maxillo-Facial Surgery\| PubMed ID: 26026886	2015
Robin sequence: A European survey on current practice patterns. Journal of cranio-maxillo-facial surgery : official publication of the European Association for Cranio-Maxillo-Facial Surgery\| PubMed ID: 26315273	2015
Non-surgical and surgical interventions for airway obstruction in children with Robin Sequence. Journal of cranio-maxillo-facial surgery : official publication of the European Association for Cranio-Maxillo-Facial Surgery\| PubMed ID: 27876376	2016
Social inequalities and dental caries in six-year-old children from the Netherlands. Journal of dentistry\| PubMed ID: 28450065	2017
Ensemble landmarking of 3D facial surface scans. Scientific reports\| PubMed ID: 29311563	2018
Automated human skull landmarking with 2D Gabor wavelets. Physics in medicine and biology\| PubMed ID: 29676286	2018
Feeding difficulties in craniofacial microsomia: A multicenter retrospective analysis of 755 patients. Journal of cranio-maxillo-facial surgery : official publication of the European Association for Cranio-Maxillo-Facial Surgery\| PubMed ID: 30158061	2018
Fractures in school age children in relation to sex and ethnic background: The Generation R Study. Bone\| PubMed ID: 30677542	2019
Femoral stress is prominently associated with fracture risk in children: The Generation R Study. Bone\| PubMed ID: 30798002	2019
Depth of invasion in early stage oral cavity squamous cell carcinoma: The optimal cut-off value for elective neck dissection. Oral oncology\| PubMed ID: 32769035	2020

Eppo B. Wolvius

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