Anatomical Deformities Research Articles

Eagle’s Syndrome: An Unusual cause of throat pain-Case Study

Eagle's syndrome or styalgia is characterised by the anatomical bone deformity of the styloid process, as identified by Wat W. Eagle in 19491. An aggregate of symptoms caused by the elongation and severe calcification of the temporal bone's styloid process, as well as calcification of the ligaments attached to this process, including the styloid and stylomandibular ligaments, have been identified2. The styloid process is typically 20 to 30 mm in length, and patients with elongated styloid processes of 40 mm or longer have clinical distress 1,3 . This styloid process elongation could be unilateral or bilateral 4. It affects around 4% of the general population, with 3:1 female predominance, however only 4% of these people experience associated symptoms 3. Eagle mainly characterized two syndromes: “classic styloid syndrome” following tonsillectomy, and “stylocarotid syndrome” unrelated to tonsillectomy6. The “styloidogenic jugular compression syndrome”, a third variation of Eagle syndrome, was recently identified, in which the jugular vein is squeezed, resulting in cerebral venous hypertension and, most commonly, headaches1.

Technical note: A method to synthesize magnetic resonance images in different patient rotation angles with deep learning for gantry-free radiotherapy.

Recently, patient rotating devices for gantry-free radiotherapy, a new approach to implement external beam radiotherapy, have been introduced. When a patient is rotated in the horizontal position, gravity causes anatomic deformation. For treatment planning, one feasible method is to acquire simulation images at different horizontal rotation angles. This study aimed to investigate the feasibility of synthesizing magnetic resonance (MR) images at patient rotation angles of 180° (prone position) and 90° (lateral position) from those at a rotation angle of 0° (supine position) using deep learning. This study included 23 healthy male volunteers. They underwent MR imaging (MRI) in the supine position and then in the prone (23 volunteers) and lateral (16 volunteers) positions. T1-weighted fast spin echo was performed for all positions with the same parameters. Two two-dimensional deep learning networks, pix2pix generative adversarial network (pix2pix GAN) and CycleGAN, were developed for synthesizing MR images in the prone and lateral positions from those in the supine position, respectively. For the evaluation of the models, leave-one-out cross-validation was performed. The mean absolute error (MAE), Dice similarity coefficient (DSC), and Hausdorff distance (HD) were used to determine the agreement between the prediction and ground truth for the entire body and four specific organs. For pix2pix GAN, the synthesized images were visually bad, and no quantitative evaluation was performed. The quantitative evaluation metrics of the body outlines calculated for the synthesized prone and lateral images using CycleGAN were as follows: MAE, 35.63±3.98 and 40.45±5.83, respectively; DSC, 0.97±0.01 and 0.94±0.01, respectively; and HD (in pixels), 16.74±3.55 and 31.69±12.03, respectively. The quantitative metrics of the bladder and prostate performed were also promising for both the prone and lateral images, with mean values>0.90 in DSC (p>0.05). The mean DSC and HD values of the bilateral femur for the prone images were 0.96 and 3.63 (in pixels), respectively, and 0.78 and 12.65 (in pixels) for the lateral images, respectively (p<0.05). The CycleGAN could synthesize the MRI at lateral and prone positions using images at supine position, and it could benefit gantry-free radiation therapy.

Postoperative Clinical and Radiological Analysis of Deviated Noses.

Anatomical deformities can greatly alter nasal function, which can be largely corrected during septoplasty and septorhinoplasty operations. In this study, we aimed to objectively measure the results of septoplasty surgeries of deviated noses with radiological analysis and compare the results with clinical evaluations. Forty patients who were undergoing septorhinoplasty were included in the study. Patients were evaluated with preoperative and postoperative paranasal computed tomography scan measurements and satisfaction surveys. Preoperative and postoperative mean ± SD septal deviation angle measurements were 11.9 ± 5.3 degrees and 6.5 ± 3.1 degrees, respectively. Preoperative and postoperative mean ± SD septal deviation distance measurements were 7.3 ± 4 and 3 ± 1.3 mm, respectively. Preoperative and postoperative mean ± SD oblique conchal measurement on the deviated side was 17.3 ± 3.2 and 13.4 ± 2.8, respectively. Preoperative and postoperative mean ± SD patient satisfaction survey scores were 17 ± 1.9 and 4.5 ± 1.9 points, respectively. To obtain a nose with a greatly improved functional gains, especially in heavy deviated noses, is an important goal in septorhinoplasty surgery. It is essential to apply the technique that will benefit the patient. The most important success criterion seems to be the regression of the clinical complaints of the patients, which can be proven objectively with computed tomography scan measurements.

Comparative estimation of pleural effusion volume based on lateral decubitus position of chest x-ray and CT scan imaging

Previous study using thoracic phantom for estimating fluid volume has been obtained which represents the case of pleural effusion based on the size of the x-ray radiograph. The models are obtained in the form of three equations, the pleural effusion volume as a function of height, length times the height, and area of the radiograph image. The three models of estimation have high linearity with ratio value more than 0.988, higher than the modelling measurement using ultrasonography modality. The modelling is expected to give a contribution on developing method for helping clinicians estimate the pleural effusion volume as a basic for performing fluid aspiration and to monitor the therapy. However, because modelling is developed using phantoms, then to be applied clinically, further research is needed for its application to patients. The height function model yields correlation value of 0.966 and paired T-test value of 0.892. The height times length function model yields correlation value of 0.982 and paired T-test value of 0.611. The area function model yields correlation value of 0.997 and paired T-test value of 0.647. From the three equations, measurement of estimated pleural effusion volume using area function on chest x-ray lateral decubitus position is the most appropriate equation. Corresponding to the results of the measurement of gold standard using a CT scan. Height measurement is the measurement that is the fastest and easiest in the application. Limitation of the study is it only can be done in right lateral decubitus position of the patient, and also cannot be applied to patients with condition such as post lung surgery, massive subpulmonic/ supradiaphragmatic pleural effusion, empyema, an atypical pleural effusion such as septated, encapsulated, loculated pleural effusion and anatomical deformity, scoliosis, or abnormalities of thoracic cavity.

Forensic Facial Approximation of 5000-Year-Old Female Skull from Shell Midden in Guar Kepah, Malaysia

Forensic facial approximation was applied to a 5000-year-old female skull from a shell midden in Guar Kepah, Malaysia. The skull was scanned using a computed tomography (CT) scanner in the Radiology Department of the Hospital Universiti Sains Malaysia using a Light Speed Plus scanner with a 1 mm section thickness in spiral mode and a 512 × 512 matrix. The resulting images were stored in Digital Imaging and Communications in Medicine (DICOM) format. A three-dimensional (3D) model of the skull was obtained from the CT scan data using Blender’s 3D modelling and animation software. After the skull was reconstructed, it was placed on the Frankfurt plane, and soft tissue thickness markers were placed based on 34 Malay CT scan data of the nose and lips. The technique based on facial approximation by data extracted from facial measurements of living individuals showed greater anatomical coherence when combined with anatomical deformation. The facial approximation in this study will pave the way towards understanding face prediction based on skull structures, soft tissue prediction rules, and soft tissue thickness descriptors.

Deformable 3D-2D image registration and analysis of global spinal alignment in long-length intraoperative spine imaging.

Spinal deformation during surgical intervention (caused by patient positioning and/or the correction of malalignment) confounds conventional navigation due to the assumptions of rigid transformation. Moreover, the ability to accurately quantify spinal alignment in the operating room would provide an assessment of the surgical product via metrics that correlate with clinical outcomes. A method for deformable 3D-2D registration of preoperative CT to intraoperative long-length tomosynthesis images is reported for an accurate 3D evaluation of device placement in the presence of spinal deformation and automated evaluation of global spinal alignment (GSA). Long-length tomosynthesis ("Long Film," LF) images were acquired using an O-arm imaging system (Medtronic, Minneapolis USA). A deformable 3D-2D patient registration was developed using multi-scale masking (proceeding from the full-length image to local subvolumes about each vertebra) to transform vertebral labels and planning information from preoperative CT to the LF images. Automatic measurement of GSA (main thoracic kyphosis [MThK] and lumbar lordosis [LL]) was obtained using a spline fit to registered labels. The "Known-Component Registration" method for device registration was adapted to the multi-scale process for 3D device localization from orthogonal LF images. The multi-scale framework was evaluated using a deformable spine phantom in which pedicle screws were inserted, and deformations were induced over a range in LL ∼25°-80°. Further validation was carried out in a cadaver study with implanted pedicle screws and a similar range of spinal deformation. The accuracy of patient and device registration was evaluated in terms of 3D translational error and target registration error, respectively, and the accuracies of automatic GSA measurements were compared to manual annotation. Phantom studies demonstrated accurate registration via the multi-scale framework for all vertebral levels in both the neutral and deformed spine: median (interquartile range, IQR) patient registration error was 1.1mm (0.7-1.9mm IQR). Automatic measures of MThK and LL agreed with manual delineation within -1.1°±2.2° and 0.7°±2.0° (mean and standard deviation), respectively. Device registration error was 0.7mm (0.4-1.0mm IQR) at the screw tip and 0.9° (1.0°-1.5°) about the screw trajectory. Deformable 3D-2D registration significantly outperformed conventional rigid registration (p<0.05), which exhibited device registration errors of 2.1mm (0.8-4.1mm) and 4.1° (1.2°-9.5°). Cadaver studies verified performance under realistic conditions, demonstrating patient registration error of 1.6mm (0.9-2.1mm); MThK within -4.2°±6.8° and LL within 1.7°±3.5°; and device registration error of 0.8mm (0.5-1.9mm) and 0.7° (0.4°-1.2°) for the multi-scale deformable method, compared to 2.5mm (1.0-7.9mm) and 2.3° (1.6°-8.1°) for rigid registration (p<0.05). The deformable 3D-2D registration framework leverages long-length intraoperative imaging to achieve accurate patient and device registration over the extended lengths of the spine (up to 64cm) even with strong anatomical deformation. The method offers a new means for the quantitative validation of spinal correction (intraoperative GSA measurement) and the 3D verification of device placement in comparison to preoperative images and planning data.

Erring Characteristics of Deformable Image Registration-Based Auto-Propagation for Internal Target Volume in Radiotherapy of Locally Advanced Non-Small Cell Lung Cancer.

PurposeRespiratory motion of locally advanced non-small cell lung cancer (LA-NSCLC) adds to the challenge of targeting the disease with radiotherapy (RT). One technique used frequently to alleviate this challenge is an internal gross tumor volume (IGTV) generated from manual contours on a single respiratory phase of the 4DCT via the aid of deformable image registration (DIR)-based auto-propagation. Through assessing the accuracy of DIR-based auto-propagation for generating IGTVs, this study aimed to identify erring characteristics associated with the process to enhance RT targeting in LA-NSCLC.Methods4DCTs of 19 patients with LA-NSCLC were acquired using retrospective gating with 10 respiratory phases (RPs). Ground-truth IGTVs (GT-IGTVs) were obtained through manual segmentation and union of gross tumor volumes (GTVs) in all 10 phases. IGTV auto-propagation was carried out using two distinct DIR algorithms for the manually contoured GTV from each of the 10 phases, resulting in 10 separate IGTVs for each patient per each algorithm. Differences between the auto-propagated IGTVs (AP-IGTVs) and their corresponding GT-IGTVs were assessed using Dice coefficient (DICE), maximum symmetric surface distance (MSSD), average symmetric surface distance (ASSD), and percent volume difference (PVD) and further examined in relation to anatomical tumor location, RP, and deformation index (DI) that measures the degree of deformation during auto-propagation. Furthermore, dosimetric implications due to the analyzed differences between the AP-IGTVs and GT-IGTVs were assessed.ResultsFindings were largely consistent between the two algorithms: DICE, MSSD, ASSD, and PVD showed no significant differences between the 10 RPs used for propagation (Kruskal–Wallis test, ps > 0.90); MSSD and ASSD differed significantly by tumor location in the central–peripheral and superior–inferior dimensions (ps < 0.0001) while only in the central–peripheral dimension for PVD (p < 0.001); DICE, MSSD, and ASSD significantly correlated with the DI (Spearman’s rank correlation test, ps < 0.0001). Dosimetric assessment demonstrated that 79% of the radiotherapy plans created by targeting planning target volumes (PTVs) derived from the AP-IGTVs failed prescription constraints for their corresponding ground-truth PTVs.ConclusionIn LA-NSCLC, errors in DIR-based IGTV propagation present to varying degrees and manifest dependences on DI and anatomical tumor location, indicating the need for personalized consideration in designing RT internal target volume.

Deep learning-based synthetization of real-time in-treatment 4D images using surface motion and pretreatment images: A proof-of-concept study.

To develop a deep learning model that maps body surface motion to internal anatomy deformation, which is potentially applicable to dose-free real-time 4D virtual image-guided radiotherapy based on skin surface data. Body contours were segmented out of 4DCT images. Deformable image registration algorithm was used to register the end-of-exhalation (EOE) phase to other phases. Deformation vector field was dimension-reduced to the first two principal components (PCs). A deep learning model was trained to predict the two PC scores of each phase from surface displacement. The instant deformation field can then be reconstructed, warping EOE image to obtain real-time CT image. This approach was validated on 4D XCAT phantom, the public DIR-Lab, and 4D-Lung dataset respectively, with and without simulated noise. Validation accuracy of the tumor centroid trajectory was observed as 0.04 ± 0.02mm on XCAT phantom. For the DIR-Lab dataset, 300 landmarks were annotated on the end-of-inhalation (EOI) images of each patient, and the mean displacements between their predicted and reference positions were below 2mm for all studied cases. For the 4D-Lung dataset, the average dice coefficients ± std between predicted and reference tumor contours at EOI phase were 0.835 ± 0.092 for all studied cases. A deep learning-based approach was proposed and validated to predict internal anatomy deformation from the surface motion, which is potentially applicable to on-line target navigation for accurate radiotherapy based on real-time 4D skin surface data and pretreatment images.

Using A modified quickert procedure combined with prolapsed fat and preseptal orbicularis muscle removal to correct involutional lower eyelid entropion in Asians

PurposeTo propose a modified Quickert procedure combined with prolapsed fat and preseptal orbicularis muscle removal which corrects involutional lower eyelid entropion, and to validate the procedure as an adequate surgical management according to anatomical deformities and pathogenesis of Asian patients. MethodsNinety-five patients (45 men, 50 women; 108 eyelids [55 right eyes, 53 left eyes]) who underwent this modified surgical procedure with a minimum follow-up period of 2 months were examined. All pre- and post-operative evaluations and surgical procedure were performed exclusively from the same oculoplastic surgeon. Postoperative results, recurrence rate, and complications were assessed. ResultsThe mean follow-up period was 13.33 months (range, 2–67 months). Of the 108 eyelids, 4 developed recurrent entropion with trichiasis, corresponding to an overall recurrence rate of 3.70%. No major complications, such as overcorrection (ectropion), symblepharon, infection, or wound dehiscence, occurred during the follow-up period after surgery. Of these 4 eyelids exhibiting recurrence, 3 occurred within 10 months and 1 occurred 49 months after surgery. Three recurrent patients received secondary surgery for re-correction with successful results. ConclusionThe modified Quickert procedure combined with prolapsed fat and preseptal orbicularis muscle removal not only demonstrated safety and effectiveness, but also led to low rate of recurrence and complications. It could be a strategy for correction of involutional entropion in Asian patients.

Cryoablation as an effective treatment for desmoid tumors: A single-institution case series.

e23543 Background: Desmoid tumors are locally invasive mesenchymal neoplasms of fibroblastic origin arising in deep soft tissue. Despite a rare incidence of 2.4-4.3 per one million and an inability to metastasize, desmoid tumors can cause significant morbidity by invading surrounding structures, causing pain, anatomic deformities, and, in some cases, death. Due to the high post-excision recurrence rate (21-29%) and frequent spontaneous regression or stabilization (50-88%), active surveillance is the first-line treatment for desmoid tumors. Most therapeutic agents only achieve tumor stability and response rates of 10-30%. As such, a large subset of patients face disease progression without an effective therapeutic option. In this context, percutaneous cryoablation arises as a novel treatment for desmoid tumors. This retrospective chart review case series aims to describe the effectiveness of cryoablation in the treatment of desmoid tumors. Methods: We retrospectively reviewed medical records of patients with a pathologically confirmed desmoid tumor who received computed tomography (CT) guided percutaneous cryoablation at a single academic hospital between 2010 and 2021. We defined objective response rate (ORR) as the percentage of patients who have partial or complete response to cryoablation. Disease progression (PD), Stable Disease (SD), Partial Response (PR), and Complete Response (CR) were defined per mRECIST criteria. Results: We identified nine patients (8 female, mean age 33) with desmoid tumors who underwent percutaneous cryoablation. The most common tumor location was the abdominal wall (n = 5,) and the median longer axis tumor size was 9.5 cm (range: 4.5-16 cm). Seven patients received previous systemic treatments. Sorafenib (n = 6) was the most common systemic therapeutic option, followed by methotrexate/vinblastine, Adriamycin/dacarbazine, tamoxifen, nirogacestat, and sulindac. Before cryoablation, six of the seven patients receiving systematic therapies had PD; one had SD. After cryoablation, seven underwent post-cryoablation imaging. Mean time to initial post-op follow-up was 38.85 days (range: 22-60 days). Six patients achieved PR (66.67%), one patient maintained SD (11.11%), and two (22.22%) were lost to follow-up. Two patients with PR regressed to SD two and three months after initial post-cryoablation imaging, respectively, and one with SD improved to PR after eleven months. As such, ORR was 71.43% (95% CI: 0.352 to 1.08). Conclusions: Our data support cryoablation as an effective therapy for decreasing tumor burden in multi-treatment resistant desmoid tumor patients. Although larger studies are needed to assess efficacy and safety, with an ORR of over 70% and a disease control rate of over 75%, cryoablation demonstrates promising results without the toxicity of systemic therapy and thus may be an effective strategy for multi-treatment resistant desmoid tumors.

Minimally Invasive Double Level Osteotomy in Severe Knee Varus: Pearls and Pitfalls

Minimally invasive double-level osteotomy (DLP) surgery is performed in severe knee varus, when extra-articular deformity is identified in both the distal femur and proximal tibia. The main advantage is to maintain a horizontal joint line and avoid creating secondary anatomic deformities. This article considers the pearls and pitfalls in performing minimally invasive DLO surgery.

Adaptive Proton Therapy of Pediatric Head and Neck Cases Using MRI-Based Synthetic CTs: Initial Experience of the Prospective KiAPT Study.

Simple SummaryRadiation therapy with protons facilitates highly conformal dose distributions. Thus, normal tissue can be spared effectively, which is a benefit, especially for children. Magnetic resonance imaging (MRI) is ideally suited to assess anatomical changes during the radiation course due to its superior soft tissue contrast and non-existent X-ray exposure. The MRI data have to be transformed to X-ray computed tomography (CT) images, which form the basis of treatment planning. This is conducted by capturing anatomical deformations between MRIs acquired at different times and by warping the planning CT according to these deformations. This procedure was applied in a prospective study enrolling pediatric head and neck cases. The preliminary evaluation of eleven patients with mainly rhabdomyosarcoma diagnosis and at craniofacial and base of skull tumor sites show that neither the deterioration of the target volume coverage nor an increased dose to organs-at-risk over the treatment course is a concern.Background and Purpose: Interfractional anatomical changes might affect the outcome of proton therapy (PT). We aimed to prospectively evaluate the role of Magnetic Resonance Imaging (MRI) based adaptive PT for children with tumors of the head and neck and base of skull. Methods: MRI verification images were acquired at half of the treatment course. A synthetic computed tomography (CT) image was created using this MRI and a deformable image registration (DIR) to the reference MRI. The methodology was verified with in-silico phantoms and validated using a clinical case with a shrinking cystic hygroma on the basis of dosimetric quantities of contoured structures. The dose distributions on the verification X-ray CT and on the synthetic CT were compared with a gamma-index test using global 2 mm/2% criteria. Results: Regarding the clinical validation case, the gamma-index pass rate was 98.3%. Eleven patients were included in the clinical study. The most common diagnosis was rhabdomyosarcoma (73%). Craniofacial tumor site was predominant in 64% of patients, followed by base of skull (18%). For one individual case the synthetic CT showed an increase in the median and dose on the spinal cord from 20.5 GyRBE to 24.8 GyRBE and 14.7 GyRBE to 25.1 GyRBE, respectively. Otherwise, doses received by OARs remained relatively stable. Similarly, the target volume coverage seen by and remained unchanged. Conclusions: The method of transferring anatomical changes from MRIs to a synthetic CTs was successfully implemented and validated with simple, commonly available tools. In the frame of our early results on a small cohort, no clinical relevant deterioration for neither PTV coverage nor an increased dose burden to OARs occurred. However, the study will be continued to identify a pediatric patient cohort, which benefits from adaptive treatment planning.

The Y plane is a reliable CT-based reference for glenoid component positioning in shoulder arthroplasty

PurposeTo determine the reliability of anatomic references for mediolateral component positioning in shoulder arthroplasty.Materials and methodsThe computed tomography scans of 86 shoulders free of arthritic or anatomic deformities were studied. Two surgeons independently digitized a series of points, including the intersection of the 3 bone branches of the scapular spine (Y), the center of the glenoid surface (G), the most medial point of the scapula (MS), the cortical convergence (CC) of the anterior and posterior margins of the glenoid, the base of the coracoid (BC), the anterior (HA) and posterior (HP) margins of the subchondral bone.ResultsThe mean mediolateral distances between G and Y, BC, CC were respectively − 19.6 mm, − 1.5 mm, and − 36.8 mm. The consistency of anatomic landmarks was greatest for Y (standard deviation (SD) =2.3 mm; interquartile range (IQR) =3 mm), compared to BC (SD = 4.6 mm; IQR = 7 mm), and CC (SD = 6.6 mm; IQR = 8 mm). The repeatability of anatomic landmarks was excellent for all measurements. The mean ratios (relative to humeral head size) of distances between G and Y, BC, CC were respectively − 0.45, − 0.04, and − 0.85. The consistency of ratios was greatest for Y (SD = 0.05; IQR = 0.06), compared to BC (SD = 0.11; IQR = 0.14), and CC (SD = 0.13; IQR = 0.17). The repeatability of ratios was excellent for Y and BC, while it was good for CC.ConclusionsThe Y-plane is a reliable reference for glenoid component positioning in shoulder arthroplasty, with a consistent distance from the center of the glenoid surface, and could therefore be suitable for preoperative planning.Study designLevel III, comparative anatomic study.

Gender specific considerations in septorhinoplasty, a retrospective observational study and review of the literature

IntroductionIn our service experience, we found we had a high proportion of male patients undergoing septorhinoplasty. This encouraged us to research gender specific differences in anatomy, surgical techniques, expectations and outcomes. MethodsWe performed a retrospective chart review of patients who have had rhinoplasty surgery under a single otolaryngology consultant with a special interest in rhinoplasty. Patient information and results of the 10-Item Standardized Cosmesis and Health Nasal Outcomes Survey for Functional and Cosmetic Rhinoplasty pre and post-surgery were collected. ResultsThere was no statistically significant difference in the mean pre-operative symptom (29.31 vs 32.29 p = 0.559), change in symptom (23.25 vs 24.14 p = 0.827) or satisfaction scores (8.69 vs 7.29 p = 0.089) between male and female patients. A discussion on gender specific anatomical features and deformities is presented. ConclusionAll patients reported improved symptoms and high levels of satisfaction. Careful patient counselling and patient-specific surgical planning help to achieve optimal outcomes.

The Facial Reconstruction of a Mesolithic Dog, Muge, Portugal

This paper presents the facial reconstruction of a Mesolithic dog whose skeleton was recovered from the Muge shell middens (Portugal) in the 19th century. We used the anatomical deformation approach based on a collection of computer tomography images as an attempt to reconstruct the Muge dog’s head appearance. We faced a few challenges due to the level of bone displacement and the absence of some cranium anatomical parts, as well as accurate information on soft tissue thickness for modern dogs. This multidisciplinary study combined anatomical, veterinary, zooarchaeological, artistic and graphic aspects to allow for the facial reconstruction of the Muge dog. Albeit an approximation, it confers a recognition to this prehistoric finding.

The report of a rare deformed eagle ray (Myliobatiformes: Myliobatidae) tooth plate from the Neogene of Calvert Cliffs, Maryland, U.S.A.

An isolated and deformed lower tooth plate of an eagle ray (Aetomylaeus sp., Myliobatidae, Myliobatiformes) is reported herein from the Miocene deposits along Calvert Cliffs, Maryland, U.S.A. Deformed myliobatid tooth plates like this, either fossil or modern, are exceedingly rare. All medial teeth are deformed/skewed such that the right side of each tooth forms an angle of about 10 degrees to the transverse axis of the dental plate. The skewed abnormal form of the teeth in USNM PAL 726325 is not thought to be the result of modern or taphonomic deformation. Rather, the deformity exhibited by USNM PAL 726325 gives every indication that successive similarly deformed teeth came about as a result of a persistent anatomical deformity of the dental lamina. From the consistency in the deformed shape of each tooth, it would appear as though the dental lamina retained this anomalous shape at least throughout the time represented by the age of the tooth plate. If this interpretation is correct, the deformity was not fatal and did not significantly impair the functionality of the tooth pavement over a protracted part (or all) of the individual's life span.

Innovative artificial lesions to mimic difficult airway pathology in cadavers, supporting airway management training

BackgroundClinicians working in anesthesiology or critical care medicine often face difficult airway situations. Moreover, time is limited to make the right decisions while securing the airway for critically ill patients. Although the modern airway management approach is strategy-based, it remains essential to provide an adequate level of training to acquire technical skills. Cadaver-based skill training is considered to be one of the highest levels of education. AimUsing an innovative method we aimed to create realistic artificial lesions making airway management difficult on specially soft-fixed human preparations. MethodsWe produced submucosal upper and lower airway lesions by injecting green-coloured liquid silicone. First, 10 non-fixed human head and neck visceral complexes were injected by suprahyoidal, infrahyoidal or transcricothyroidal lateral punctures. After the silicone crosslinked, the preparations were fixed (4% formaldehyde) and the lesions were visualized by sections. Then in situ lesions were implanted by percutaneous puncture of 5 Thiel-fixed head preparations. Tracheal stenosis was achieved by external ligature. Videolaryngoscopic images were taken under comparable parameters before and after implantation. ResultsThe lesions created proved to be realistic in their localisation and shape. The tissues were optimally infiltrated and not fragile. In the in situ models significant airway stenoses and anatomical deformities were induced. ConclusionAs first step of a long-term project the current paper has only attempted to communicate modelling as a technical report on creating standardized artificial airway difficulties for education or research. Our models provide an opportunity to increase the anatomical diversity and realism of airway management courses. A systematically designed educational unit consisting of several cadavers is an invaluable tool in training, the role of which is planned to be analyzed.

Regeneration of temporomandibular joint using in vitro human stem cells: A review.

Temporomandibular joint disorders (TMDs) range from gross anatomic deformities of the disc and hard tissue to functional disturbances. Traditional treatment of TMDs includes physical therapy, use of appliances, pharmacological, surgical and psychological interventions. However, during the late stage of TMDs, conventional management often results in inadequate relief of symptoms. Stem cell‐based tissue regeneration has been studied extensively in joint regeneration, including the Temporomandibular Joint (TMJ). This study aims to review the potential of various human stem cells (HSC) for the regeneration of the TMJ. In vitro studies using human mesenchymal stem cells cultured under different conditions to evaluate regeneration of TMJ related structures were searched on PubMed, EMBASE, Cochrane, and Web of Science up to March 2020. In vitro studies utilized several different types of stem cells under varying conditions. Increased osteogenesis and/or chondrogenesis were noted with stem cell interventions compared to control groups on Alkaline Phosphatase (ALP) activity, Col‐I, Col‐II, Col‐X, RUNX2, LPL, and Aggrecan mRNA expression. This review emphasizes the potential of stem cell therapies in the regeneration of TMJ‐related structures. However, further in vivo studies are required to evaluate the efficacy and safety of these therapies in humans.

Anthropometric three-dimensional computed tomography reconstruction measurements of the acetabulum in children/adolescents.

The key element for differentiation between normal anatomical variants and pathological deformities is the prior definition of normal ranges for anthropometric parameters of acetabulum according to each age group. Aim of the present study is to analyze the development of the acetabulum in children/adolescents by accurate anthropometric measurements using 3D-CT scans and determine the variations occurring depending on age, gender and/or side. This retrospective observational study included 85 patients (170 hips) under 15 years of age (0-15) undergoing 1.5mm CT scanning for non-hip related reasons. The measurements were performed by 2 board-certified orthopaedic surgeons. Each year of life represented an age group forming a total of 16 groups. Median number of patients per age group was 12 (range 4-16). The anthropometric parameters included acetabular volume, inclination, version, depth (coronal and axial), width (coronal and axial), Tönnis angle as well as anterior and posterior acetabular sector angles. Mean values, range, standard deviation, p-values, intra- and interrater reliability were calculated. All measurement values correlated significantly with age. Statistically, there was no side or gender related difference. Rapid growth phases were observed at the age of 11-12. The inter- and intrarater reliability was high (range ICC 0.8-0.99, Cronbach alpha 0.86-0.99, Bland-Altman good agreement). The present data provides age- and gender-related normative values as well as growth phases describing acetabular morphology. It should help paediatricians as well as paediatric and orthopaedic surgeons as a tool for early diagnosis of deformity and guidance for possible procedures.

Fully automatic segmentation of craniomaxillofacial CT scans for computer-assisted orthognathic surgery planning using the nnU-Net framework.

To evaluate the performance of the nnU-Net open-source deep learning framework for automatic multi-task segmentation of craniomaxillofacial (CMF) structures in CT scans obtained for computer-assisted orthognathic surgery. Four hundred and fifty-three consecutive patients having undergone high-resolution CT scans before orthognathic surgery were randomly distributed among a training/validation cohort (n = 300) and a testing cohort (n = 153). The ground truth segmentations were generated by 2 operators following an industry-certified procedure for use in computer-assisted surgical planning and personalized implant manufacturing. Model performance was assessed by comparing model predictions with ground truth segmentations. Examination of 45 CT scans by an industry expert provided additional evaluation. The model's generalizability was tested on a publicly available dataset of 10 CT scans with ground truth segmentation of the mandible. In the test cohort, mean volumetric Dice similarity coefficient (vDSC) and surface Dice similarity coefficient at 1mm (sDSC) were 0.96 and 0.97 for the upper skull, 0.94 and 0.98 for the mandible, 0.95 and 0.99 for the upper teeth, 0.94 and 0.99 for the lower teeth, and 0.82 and 0.98 for the mandibular canal. Industry expert segmentation approval rates were 93% for the mandible, 89% for the mandibular canal, 82% for the upper skull, 69% for the upper teeth, and 58% for the lower teeth. While additional efforts are required for the segmentation of dental apices, our results demonstrated the model's reliability in terms of fully automatic segmentation of preoperative orthognathic CT scans. • The nnU-Net deep learning framework can be trained out-of-the-box to provide robust fully automatic multi-task segmentation of CT scans performed for computer-assisted orthognathic surgery planning. • The clinical viability of the trained nnU-Net model is shown on a challenging test dataset of 153 CT scans randomly selected from clinical practice, showing metallic artifacts and diverse anatomical deformities. • Commonly used biomedical segmentation evaluation metrics (volumetric and surface Dice similarity coefficient) do not always match industry expert evaluation in the case of more demanding clinical applications.