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Present‐day crocodylians exhibit a remarkably akinetic skull with a highly modified braincase. We present a comprehensive description of the neurocranial osteology of extant crocodylians, with notes on the development of individual skeletal elements and a discussion of the terminology used for this project. The quadrate is rigidly fixed by multiple contacts with most braincase elements. The parabasisphenoid is sutured to the pterygoids (palate) and the quadrate (suspensorium); as a result, the basipterygoid joint is completely immobilized. The prootic is reduced and externally concealed by the quadrate. It has a verticalized buttress that participates in the canal for the temporal vasculature. The ventrolateral processes of the otoccipitals completely cover the posteroventral region of the braincase, enclose the occipital nerves and blood vessels in narrow bony canals and also provide additional sutural contacts between the braincase elements and further consolidate the posterior portion of the crocodylian skull. The otic capsule of crocodylians has a characteristic cochlear prominence that corresponds to the lateral route of the perilymphatic sac. Complex internal structures of the otoccipital (extracapsular buttress) additionally arrange the neurovascular structures of the periotic space of the cranium. Most of the braincase elements of crocodylians are excavated by the paratympanic pneumatic sinuses. The braincase in various extant crocodylians has an overall similar structure with some consistent variation between taxa. Several newly observed features of the braincase are present in Gavialis gangeticus and extant members of Crocodylidae to the exclusion of alligatorids: the reduced exposure of the prootic buttress on the floor of the temporal canal, the sagittal nuchal crest of the supraoccipital projecting posteriorly beyond the postoccipital processes and the reduced paratympanic pneumaticity. The most distinctive features of the crocodylian braincase (fixed quadrate and basipterygoid joint, consolidated occiput) evolved relatively rapidly at the base of Crocodylomorpha and accompanied the initial diversification of this clade during the Late Triassic and Early Jurassic. We hypothesize that profound rearrangements in the individual development of the braincases of basal crocodylomorphs underlie these rapid evolutionary modifications. These rearrangements are likely reflected in the embryonic development of extant crocodylians and include the involvement of neomorphic dermal anlagen in different portions of the developing chondrocranium, the extensive ossification of the palatoquadrate cartilage as a single expanded quadrate and the anteromedial inclination of the quadrate. [ABSTRACT FROM AUTHOR]

Background  The temple has been identified as one of the most compelling facial regions in which to seek aesthetic improvement—both locally and in the entire face—when injecting soft tissue fillers. Objective  The objective of this study is to identify influences of age, gender, and body mass index (BMI) on temporal parameters to better understand clinical observations and to identify optimal treatment strategies for treating temporal hollowing. Methods  The sample consisted of 28 male and 30 female individuals with a median age of 53 (34) years and a median BMI of 27.00 (6.94) kg/m 2. The surface area of temporal skin, the surface area of temporal bones, and the temporal soft tissue volume were measured utilizing postprocessed computed tomography (CT) images via the Hausdorff minimal distance algorithm. Differences between the investigated participants related to age, BMI, and gender were calculated. Results  Median skin surface area was greater in males compared with females 5,100.5 (708) mm 2 versus 4,208.5 (893) mm 2 (p  < 0.001) as was the median bone surface area 5,329 (690) mm 2 versus 4,477 (888) mm 2 (p  < 0.001). Males had on average 11.04 mL greater temporal soft tissue volume compared with age and BMI-matched females with p  < 0.001. Comparing the volume between premenopausal versus postmenopausal females, the median temporal soft tissue volume was 46.63 mL (11.94) versus 40.32 mL (5.69) (p  = 0.014). Conclusion  The results of this cross-sectional CT imaging study confirmed previous clinical and anatomical observations and added numerical evidence to those observations for a better clinical integration of the data. [ABSTRACT FROM AUTHOR]

Background: Previous anatomic studies have provided valuable information on the 2-dimensional course of the angular segment of the facial artery in the midface and its arterial connections. The third dimension (ie, the depth of the artery) is less well characterized.Objectives: The objective of the present study was to describe the 3-dimensional pathway of the angular segment of the facial artery and its relationship to the muscles of facial expression.Methods: The bilateral location and the depth of the midfacial segment of the facial artery was measured utilizing multi-planar computed tomographic image analyses obtained from contrast agent-enhanced cranial computed tomographic scans of 156 Caucasians aged a of 45.19 ± 18.7 years and with a mean body mass index of 25.05 ± 4.9 kg/m2.Results: At the nasal ala, the mean depth of the main arterial trunk was 13.7 ± 3.7 mm (range, 2.7-25.0 mm), whereas at the medial canthus it was 1.02 ± 0.62 mm (range, 1.0-3.0 mm). This was reflected by the arteries' relationship to the midfacial muscles: at the nasal ala superficial to levator anguli oris in 62.0% but deep to the levator labii superioris alaeque nasi in 53.6%; at the medial canthus superficial to the levator labii superioris alaeque nasi in 83.1% and superficial to the orbicularis oculi in 82.7%.Conclusions: The results presented herein confirm the high variability in the course of the angular segment of the facial artery. Various arterial pathways have been identified providing evidence that, in the midface, there is no guaranteed safe location for minimally invasive procedures. [ABSTRACT FROM AUTHOR]

Background: Due to its arterial vasculature, the nasolabial sulcus is one of the most challenging facial regions to treat when trying to ameliorate the signs of facial aging.Objectives: The aim of the present study was to provide data on the 3-dimensional course of the angular artery within the nasolabial sulcus in relation to age, gender, and body mass index to increase safety during minimally invasive treatments.Methods: Thee hundred nasolabial sulci from 75 males and 75 females of Russian Caucasian ethnic background (mean [standard deviation] age, 45.7 [18.7] years; mean body mass index, 25.14 [4.9] kg/m2) were analyzed. Bilateral multiplanar measurements were based on contrast-enhanced computed tomography cranial scans.Results: Up to 3 arteries could be identified within the nasolabial sulcus: ~90% contained 1 arterial trunk, ~9% had 2 trunks, and ~1% had 3 trunks; females had more arteries than men. The artery is located at mean depths of 21.6 mm at the oral commissure and 8.9 mm at the nasal ala. The angular artery was lateral to the nasolabial sulcus in 100% of cases; the smallest distance between the artery and the nasolabial sulcus was at the oral commissure (11.91 [7.9] mm) and the greatest was at the nasal ala (13.73 [3.9] mm).Conclusions: In contrast to current concepts, the angular artery is not located strictly subdermal to the nasolabial sulcus but at a variable depth, and in 100% of the investigated cases lateral to the nasolabial sulcus. With increasing age, the depth and lateral distance between arteries and sulci reduces significantly, underscoring the need for special caution when injecting this site. [ABSTRACT FROM AUTHOR]

Background: Age-related changes of the frontal bone in both males and females have received limited attention, although understanding these changes is crucial to developing the best surgical and nonsurgical treatment plans for this area.Objectives: To investigate age-related and gender-related changes of the forehead.Methods: Cranial computed tomographic images from 157 Caucasian individuals were investigated (10 males and 10 females from each of the following decades: 20-29 years, 30-39 years, 40-49 years, 50-59 years, 60-69 years, 70-79 years, 80-89 years, and of 8 males and 9 females aged 90-98 years). Frontal bone thickness and forehead distance measurements were carried out to analyze age and gender differences.Results: With increasing age, the size of a male forehead reduces until no significant differences to a female forehead is present at old age (P = 0.307). The thickness of the frontal bone of the lower forehead (≤4 cm cranial to the nasal root) increased slightly in both genders with increasing age. In the upper forehead (≥4 cm cranial to the nasal root), frontal bone thickness decreased significantly (P = 0.002) in males but showed no statistically significant change in thickness in females (P = 0.165).Conclusions: The shape of the frontal bone varies in young individuals of different genders and undergoes complex changes with age because of bone remodeling. Understanding these bony changes, in addition to those in the soft tissues, helps physicians choose the best surgical and nonsurgical treatment options for the forehead.Level Of Evidence:4: [ABSTRACT FROM AUTHOR]

Computed tomography (CT) has been an essential diagnostic tool during the COVID-19 pandemic. The study aimed to develop an optimal CT protocol in terms of safety and reliability. For this, we assessed the inter-observer agreement between CT and low-dose CT (LDCT) with soft and sharp kernels using a semi-quantitative severity scale in a prospective study (Moscow, Russia). Two consecutive scans with CT and LDCT were performed in a single visit. Reading was performed by ten radiologists with 3–25 years' experience. The study included 230 patients, and statistical analysis showed LDCT with a sharp kernel as the most reliable protocol (percentage agreement 74.35 ± 43.77%), but its advantage was marginal. There was no significant correlation between radiologists' experience and average percentage agreement for all four evaluated protocols. Regarding the radiation exposure, CTDIvol was 3.6 ± 0.64 times lower for LDCT. In conclusion, CT and LDCT with soft and sharp reconstructions are equally reliable for COVID-19 reporting using the "CT 0-4" scale. The LDCT protocol allows for a significant decrease in radiation exposure but may be restricted by body mass index. [ABSTRACT FROM AUTHOR]

• Usage of most spatially detailed feature maps boosts classification quality within the proposed multitask framework. • A deep convolutional network for triage of COVID-19 patients based on identification and severity quantification scores. • A carefully selected independent external test set with other lung pathologies. • Publicly released annotated data and code to ensure reproducibility. [Display omitted] The current COVID-19 pandemic overloads healthcare systems, including radiology departments. Though several deep learning approaches were developed to assist in CT analysis, nobody considered study triage directly as a computer science problem. We describe two basic setups: Identification of COVID-19 to prioritize studies of potentially infected patients to isolate them as early as possible; Severity quantification to highlight patients with severe COVID-19, thus direct them to a hospital or provide emergency medical care. We formalize these tasks as binary classification and estimation of affected lung percentage. Though similar problems were well-studied separately, we show that existing methods could provide reasonable quality only for one of these setups. We employ a multitask approach to consolidate both triage approaches and propose a convolutional neural network to leverage all available labels within a single model. In contrast with the related multitask approaches, we show the benefit from applying the classification layers to the most spatially detailed feature map at the upper part of U-Net instead of the less detailed latent representation at the bottom. We train our model on approximately 1500 publicly available CT studies and test it on the holdout dataset that consists of 123 chest CT studies of patients drawn from the same healthcare system, specifically 32 COVID-19 and 30 bacterial pneumonia cases, 30 cases with cancerous nodules, and 31 healthy controls. The proposed multitask model outperforms the other approaches and achieves ROC AUC scores of 0.87 ± 0.01 vs. bacterial pneumonia, 0.93 ± 0.01 vs. cancerous nodules, and 0.97 ± 0.01 vs. healthy controls in Identification of COVID-19, and achieves 0.97 ± 0.01 Spearman Correlation in Severity quantification. We have released our code and shared the annotated lesions masks for 32 CT images of patients with COVID-19 from the test dataset. [ABSTRACT FROM AUTHOR]