Morphometric measures and desaturations: Proposal for an index with improved accuracy for obstructive sleep apnea screening.

STUDY OBJECTIVE: To evaluate the sensitivity and specificity of the combined Kushida morphometric model (KMM) and the oxygen desaturation index (ODI) for screening individuals with obstructive sleep apnea. METHODS: Diagnostic test study with adults >18 years, both sexes, polysomnography, body mass index, neck circumference and intraoral measurements. RESULTS: 144 patients were invited; of these, 75 met the exclusion criteria. 55 individuals presented AHI ≥5 ev/h and 14, an AHI <5 ev/h. Three AHI cut-off points were evaluated: AHI ≥5, ≥15, ≥30 ev/h. When adopting the cut-off point of AHI ≥5 ev/h, the KMM showed sensitivity (SE) = 60.0 %, specificity (SP) = 71.4 % and 95 % confidence interval of the area under the curve (95 % CI of AUC) = 0.655; the combination of KMM and ODI (KMM + ODI) revealed SE = 73.0 %, SP = 71.4 % (95 % CI of AUC = 0.779) and the ODI showed SE = 76.4 % and SP = 92.9 % (95 % CI of AUC = 0.815). At the cut-off point of AHI ≥15 ev/h, the KMM presented SE = 64.1 %, SP = 76.7 % (95 % CI of AUC = 0.735); the KMM + ODI showed SE = 82.1 %, SP = 83.3 % (95 % CI of AUC = 0.895); and the ODI presented SE = 76.9 %, SP = 100.0 % (95 % CI of AUC = 0.903). For the cut-off point of AHI ≥30 ev/h, the KMM showed SE = 56.0 %, SP = 77.2 % (95 % CI of AUC = 0.722); the KMM + ODI revealed SE = 92.0 %, SP = 79.5 % (95 % CI of AUC = 0.926); and the ODI showed SE = 92.0 %, SP = 90.9 % (95 % CI of AUC = 0.941). CONCLUSION: The combination of oxygen desaturation index and Kushida morphometric model improved the sensitivity and specificity of this model regardless of obstructive sleep apnea severity suggesting greater effectiveness in risk prediction.

[Clinical anatomy of the free latissimus dorsi myocutaneous flap and its application in the restoration of giant defects of the head and neck].

PURPOSE: To investigate the feasibility and effect of free latissimus dorsi myocutaneous flap in the reconstruction of giant head and neck defects. METHODS: Free latissimus dorsi myocutaneous flap on the cadaver was simulated dissected, and measured by Image-Pro Plus 6.0 to assess the feasibility of repairing giant head and neck defects. Between May 2011 and September 2022, seven patients with giant head and neck defects of different causes repaired with the latissimus dorsi myocutaneous flap were retrospectively analyzed. RESULTS: The diameter of the initiating thoracodorsal artery was (4.03±0.56) mm, and the mean lengths of the arteriolar and venous pedicles of the latissimus dorsi myocutaneous flaps obtained from human specimens were (85.5±10.5) mm and (104±4.2) mm, respectively. Among 7 patients, 5 cases had scalp defects, the remaining 2 cases had neck defects. There were no substantial postoperative problems in the donor site, and all seven latissimus dorsi myocutaneous flaps were successfully transplanted. CONCLUSIONS: For the treatment of considerable head and neck deformities, the latissimus dorsi myocutaneous flap is an optimal muscle flap due to its abundance of tissue, enough length of vascular pedicles, and sufficient venous drainage.

Evaluation of neck ultrasound measurements as a difficult airway predictor: A prospective observational study.

This study aimed to investigate the relationship between cervical measurements and difficult airways using ultrasonographic measurements. American Society of Anesthesiologists grade I to III, male or female, 120 adult patients, undergoing elective surgery were enrolled in the study. The study involved measuring the distance of the trachea, cricoid cartilage, thyroid cartilage, vocal cord anterior commissure, and hyoid bone to the skin using a 10 to 13 MHz linear ultrasound probe in the transverse plane. Additionally, the length of the cricothyroid and thyrohyoid membranes, along with their distance from the skin, were measured using the probe in the sagittal plane. Subsequently, another experienced anesthesiologist conducted mask ventilation and intubation after the patient's induction of general anesthesia. Throughout this process, the patient was assessed for difficulties in mask ventilation, laryngoscopy, and intubation. 28 (23.3%) patients had a difficult airway. Analyzing the measurements associated with difficult airways, the most reliable predictor was the epiglottis midline-skin distance [AUC (area under the curve): 0.847, P < .001, cutoff: >19.9, sensitivity: 78.6%, specificity: 79.4%]. Additionally, other factors such as hyoid bone to skin distance, thyroid cartilage to skin distance, thyrohyoid membrane to skin distance, and vocal cord anterior commissure-skin distance were also identified as predictors for a difficult airway. The increase in the distance of the epiglottis midline, vocal cord anterior commissure, hyoid bone, thyrohyoid membrane, and thyroid cartilage to the skin at the level of the isthmus measured by ultrasonography is predictive of difficult airways. Based on our study outcomes, we assert that ultrasonographic evaluation can be used in the prediction of difficult airways.

Prevalence of insulin dysregulation in the non-obese stock-type horse and relationship with morphometric neck measurements.

Insulin dysregulation (ID), core to equine metabolic syndrome, may present without obesity. Testing for ID risk is commonly based on breed and obese phenotype but might be valuable for non-obese stock-type horses. This study aimed to determine the prevalence of ID in non-obese stock-type horses and evaluate if morphometric neck measurements (MNM) correlate with ID. Sixty-two, non-obese (BCS 5, range 2.5-6/9) stock-type horses were assessed for MNM: neck circumference at 25%, 50% (NC50), and 75% (NC75) length, and crest height. An oral sugar test (OST; 0.15 mL/kg BW corn syrup) was performed with blood taken pre- and 60 min post-OST for insulin (PREI, POSTI) and glucose (PREG, POSTG). Insulin dysregulation was defined as insulin concentration > 45 µIU/mL POSTI. Three of 62 horses were ID (4.8%; 95% CI 1.0%-13.5%). Horses with ID had greater PREG (121.0 ± 7.56 vs. 105.3 ± 1.72 mg/dL; LS means ± SEM; P = 0.04) and PREI (15.7 ± 2.63 vs. 10.5 ± 0.59 µIU/mL; P = 0.05) than normal responders. Mares had greater PREI than geldings (11.7 ± 0.76 vs. 9.4 ± 0.89 µIU/mL; P = 0.04). Stepwise regression indicated a weak relationship with crest height and POSTG (y = 51.27 + (0.88 x NC50); R2 = 0.09; P = 0.02). Post-glucose correlated with NC50 (r = 0.30; P = 0.04) and NC75 (r = 0.29; P = 0.03). This study showed 4.8% of non-obese horses had ID, warranting testing irrespective of phenotype, but only a weak association between MNM and POSTG was found.

[Predictive value of neck circumference for cardiometabolic risk in children].

Objective: To investigate the predictive value of neck circumference on cardiometabolic risk in children. Methods: This was a cross-sectional study of natural sources. As the prediction cohort, clinical data were collected from 3 443 children aged 5-14 years who underwent physical examination in the Department of Child Healthcare, Children's Hospital of Nanjing Medical University from July 2021 to September 2022. As the validation cohort for external validation, clinical data were collected from 604 children aged 5-14 years who underwent physical examination in the Department of Child Healthcare, Children's Hospital of Nanjing Medical University from October 2022 to March 2023. Height, weight, neck circumference, waist circumference and body composition were measured in both groups, and body mass index, neck circumference to height ratio (NHtR), waist circumference to height ratio, body fat percentage and skeletal muscle percentage were calculated. Systolic blood pressure, diastolic blood pressure, fasting blood glucose, blood lipid and uric acid and other cardiovascular and metabolic risk indicators were collected in both groups. The prediction cohort was further stratified into clustered and non-clustered groups based on the clustering of cardiometabolic risk factors (CCRF). Various variables between these 2 groups were compared using the Mann-Whitney U test. Pearson correlation and binary Logistic regression were conducted to investigate the correlations between neck circumference and cardiovascular metabolic risk factors. The accuracy of NHtR in predicting the CCRF was evaluated using the area under the curve (AUC) of receiver operating characteristic (ROC). The cutoff value was determined using the Youden index. The validation cohort was then divided into groups above and below the cutoff value, and the detection rate of CCRF between the 2 groups was compared using the χ2 test for validation. Results: In the prediction cohort of 3 443 children (2 316 boys and 1 127 girls), 1 395 (40.5%) children were overweight or obese, and 1 157 (33.6%) children had CCRF. Pearson correlation analysis revealed all significant positive correlations (all P<0.01) between neck circumference and systolic blood pressure (r=0.47, 0.39), diastolic blood pressure (r=0.27, 0.21), uric acid (r=0.36, 0.30), and triglycerides (r=0.20, 0.20) after adjusting for age in both males and females. Among both males and females, neck circumference both showed significant negative correlation (both P<0.01) with high-density lipoprotein cholesterol (r=-0.27, -0.28), and no correlation with fasting glucose levels (r=0.03, -0.03, both P>0.05). After adjusting for gender, age, and body fat percentage, increased body mass index, neck circumference, or waist circumference increased the risks of hypertension (OR=1.23, 1.39, 1.07, all P<0.001), hyperuricemia (OR=1.16, 1.23, 1.05, all P<0.001), hypertriglyceridemia (OR=1.08, 1.16, 1.02, all P<0.01), low high-density lipoprotein cholesterol (OR=1.10, 1.27, 1.03, all P<0.01), and the CCRF (OR=1.51, 1.73, 1.15, all P<0.01). The areas under the ROC curves of NHtR in predicting CCRF was 0.73, with sensitivity and specificity at 0.66 and 0.71, respectively. The corresponding optimal cut-off value was 0.21. Validation with 604 children confirmed that the detection of CCRF in the NHtR≥0.21 group was 3.29 times (60.5% (112/185) vs. 18.7% (79/422),χ2=107.82, P<0.01) higher compared to the NHtR <0.21 group. Conclusions: Neck circumference is associated with cardiovascular metabolic risks such as hypertension, hyperlipidemia, hyperglycemia, and hyperuricemia in children. When the NHtR is ≥0.21, there is an increased likelihood of CCRF.

Accuracy of neck circumference in the diagnosis of overweight in children.

OBJECTIVE: The objective of this study was to estimate the accuracy of measuring neck circumference as a diagnostic method for overweight in 10-year-old children. METHODS: A cross-sectional diagnostic accuracy study was performed in 2019. The population was composed of 942 school children from the municipality of Palhoça, SC, Brazil. For each measurement of the neck circumference, sensitivity, specificity, positive and negative predictive values, likelihood ratio for a positive test, and accuracy were estimated using the receiver operator characteristic curve, with body mass index as a reference. RESULTS: The estimated overall accuracy was 88.9%. For males, the accuracy was 90.1%, and for females, 88.5%. A 30.0 cm neck circumference had a sensitivity of 22.8%, a specificity of 95.4%, a positive predictive value of 76.6%, a negative predictive value of 65.3%, a likelihood ratio for a positive test of 5.0, and an accuracy of 66.7% for all students. CONCLUSION: Neck circumference showed a global accuracy of 88.9% as a method for diagnosing overweight in 10-year-old children. Predictive values showed high values, mainly starting with a neck circumference of 30 cm.

Ultrasound Evaluation of Anterior Neck Soft-Tissue Thickness to Predict Difficult Intubation in Overweight Adult Patients Posted for Surgery under General Endotracheal Anesthesia - An Observational Study.

BACKGROUND: Ultrasonographic imaging has been recently become simple portable and non-invasive adjuvant for bedside assessment of anterior neck soft tissue thickness which when measured at different levels showed to have significant role in predicting difficult laryngoscopy. AIMS AND OBJECTIVES: Primary objective was Ultrasonographic measurement of anterior neck soft tissue thickness at 3 levels -Distance from skin to hyoid bone (DSHB) -Distance from skin to thyrohyoid membrane (DSTM) -Distance from skin to anterior commissure of vocal cord(DSAC) and to compare and correlate the findings with Cooks modification of Cormack-Lehane score in predicting difficult laryngoscopy. Secondary objective was to compare and correlate the ultrasonographic measurements with conventional airway assessment methods. MATERIALS AND METHODS: After obtaining approval from the ethical committee, 90 Patients with BMI above 25 kg /m2 was enrolled for the study. A day before the surgery a thorough Preanaesthetic evaluation and assessment of the airway is done using conventional methods. Then on the day of surgery ultrasonographic measurement of anterior neck at 3 levels was done and after inducing the patients laryngoscopy was done and Cooks modification of Cormack-Lehane score assessed. RESULTS: The optimal cut off values to predict difficult laryngoscopy was 1.26, 2 and 1.2 cms for DSHB, DSTM and DSAC respectively, and among the three skin to anterior commissure of vocal cord was observed to be best USG parameter with more area under the ROC curve. CONCLUSION: USG measurement of anterior neck soft tissue thickness can be useful in predicting difficult laryngoscopy in overweight and obese patients also it had more diagnostic accuracy than conventional methods like MMS in predicting difficult laryngoscopy.

RésuméArrière-plan L'imagerie échographique est récemment devenue un simple adjuvant portable et non invasif pour l'évaluation au lit du patient de l'épaisseur des tissus mous du cou antérieur qui, lorsqu'elle est mesurée à différents niveaux, s'est avérée avoir un rôle important dans la prédiction d'une laryngoscopie difficile. Buts et objectifs L'objectif principal était la mesure échographique de l'épaisseur des tissus mous du cou antérieur à 3 niveaux -Distance de la peau à l'os hyoïde (DSHB) -Distance de la peau à la membrane thyrohyoïdienne (DSTM) -Distance de la peau à la commissure antérieure de la corde vocale (DSAC) et pour comparer et corréler les résultats avec la modification de Cooks du score de Cormack-Lehane pour prédire une laryngoscopie difficile. L'objectif secondaire était de comparer et de corréler les mesures échographiques avec les méthodes conventionnelles d'évaluation des voies respiratoires Matériels et méthodes Après avoir obtenu l'approbation du comité d'éthique, 90 patients présentant un IMC supérieur à 25 kg/m2 ont été inclus dans l'étude. Un jour avant la chirurgie, une évaluation préanesthésique approfondie et une évaluation des voies respiratoires sont effectuées à l'aide de méthodes conventionnelles. Ensuite, le jour de la chirurgie, une mesure échographique de la partie antérieure du cou à 3 niveaux a été effectuée et après l'induction des patients, une laryngoscopie a été effectuée et la modification de Cooks du score de Cormack-Lehane a été évaluée. Résultats Les valeurs seuil optimales pour prédire une laryngoscopie difficile étaient respectivement de 1,26, 2 et 1,2 cm pour DSHB, DSTM et DSAC, et parmi les trois paramètres de la peau à la commissure antérieure de la corde vocale, il a été observé que le meilleur paramètre USG avec plus de surface sous la courbe ROC Conclusion La mesure par USG de l'épaisseur des tissus mous du cou antérieur peut être utile pour prédire une laryngoscopie difficile chez les patients en surpoids et obèses. Elle a également une plus grande précision diagnostique que les méthodes conventionnelles comme le MMS pour prédire une laryngoscopie difficile.

Association between neck circumference and bone mineral loss: A cross-sectional study in Sichuan province in China.

BACKGROUND: The associations of fat distribution with bone health are debatable. We aimed to investigate the associations between neck circumference (NC) and bone mineral loss among the adult Chinese population in Sichuan province. METHODS: We examined overall NC size and NC stratums (≤35 cm, 3538 cm) with bone mineral density (BMD) at the femoral neck, lumbar spine, total hip skeletal sites in 135 men and 479 women respectively, and assessed whether adiposity, lipids, and calcium and phosphorus levels, might have a biased role in the relationship of NC and bone mineral loss with linear regression, logistic regression, and restricted cubic spline models. RESULTS: The overall NC size is not independently associated with BMD at all sites. However, stratification for NC revealed that the positive correlation between NC and BMD at all sites were significant in the NC stratum 1 (≤35 cm) in women (all p<0.05) and NC stratum 2 (3538 cm) compared with NC stratum 1 using logistic regression. However, in women, no statistically significant association was observed between NC stratum 1 and BMD values after adjustment for the same confounders. CONCLUSIONS: Our findings suggest a NC stratum-specific association between NC size and bone mineral loss in men in Sichuan province in China, but not in women.

Anatomical Insights on the Cervical Nerve for Contemporary Face and Neck Lifting: A Cadaveric Study.

BACKGROUND: Despite the significant roles it plays in the functions of the platysma and lower lip, the cervical branch of the facial nerve is often overlooked compared to other branches, but its consideration is critical for ensuring the safety of neck surgeries. OBJECTIVES: The aim of this study was to clarify the anatomical discrepancies associated with the cervical branch of the facial nerve to enhance surgical safety. METHODS: The study utilized 20 fresh-frozen hemiheads. A 2-stage surgical procedure was employed, beginning with an initial deep-plane facelift including extensive neck dissection, followed by a superficial parotidectomy on fresh-frozen cadavers. This approach allowed for a thorough exploration and mapping of the cervical nerve in relation to its surrounding anatomical structures. RESULTS: Upon exiting the parotid gland, the cervical nerve consistently traveled beneath the investing layer of the deep cervical fascia for a brief distance, traversing the deep fascia to travel within the areolar connective tissue before terminating anteriorly in the platysma muscle. A single branch was observed in 2 cases, while 2 branches were noted in 18 cases. CONCLUSIONS: The cervical nerve's relatively deeper position below the mandible's angle facilitates a safer subplatysmal dissection via a lateral approach for the release of the cervical retaining ligaments. Due to the absence of a protective barrier, the nerve is more susceptible to injuries from direct trauma or thermal damage caused by electrocautery, especially during median approaches.

The Late Cretaceous eutherian Zalambdalestes reveals unique axis and complex evolution of the mammalian neck.

The typical mammalian neck consisting of seven cervical vertebrae (C1-C7) was established by the Late Permian in the cynodont forerunners of modern mammals. This structure is precisely adapted to facilitate movements of the head during feeding, locomotion, predator evasion, and social interactions. Eutheria, the clade including crown placentals, has a fossil record extending back more than 125 million years revealing significant morphological diversification in the Mesozoic. Yet very little is known concerning the early evolution of eutherian cervical morphology and its functional adaptations. A specimen of Zalambdalestes lechei from the Late Cretaceous of Mongolia boasts exceptional preservation of an almost complete series of cervical vertebrae (C2-C7) revealing a highly modified axis (C2). The significance of this cervical morphology is explored utilizing an integrated approach combining comparative anatomical examination across mammals, muscle reconstruction, geometric morphometrics and virtual range of motion analysis. We compared the shape of the axis in Zalambdalestes to a dataset of 88 mammalian species (monotremes, marsupials, and placentals) using three-dimensional landmark analysis. The results indicate that the unique axis morphology of Zalambdalestes has no close analog among living mammals. Virtual range of motion analysis of the neck strongly implies Zalambdalestes was capable of exerting very forceful head movements and had a high degree of ventral flexion for an animal its size. These findings reveal unexpected complexity in the early evolution of the eutherian cervical morphology and suggest a feeding behavior similar to insectivores specialized in vermivory and defensive behaviors in Zalambdalestes akin to modern spiniferous mammals.

Neck Circumference in Polycystic Ovary Syndrome: A Systematic Review and Bootstrapped Meta-Analysis with GRADE Approach.

INTRODUCTION: Our aim was to perform a systematic review and meta-analysis for the association of neck circumference (NC) in polycystic ovary syndrome (PCOS) patients as compared to non-PCOS controls. METHODS: Primarily the PubMed/MEDLINE database and others such as SCOPUS, Google Scholar, Cochrane Library, were searched up to November 15, 2023 for observational studies comparing NC in PCOS versus non-PCOS women. The mean and SD values of NC and other covariates in PCOS and control groups were extracted by two independent reviewers, and the quality and risk of bias assessment was done using Newcastle-Ottawa Scale. The meta-analysis employed combined standardized mean differences (SMD) with 95% confidence intervals (CI) to compare NC between PCOS patients and controls. The heterogeneity and validity were addressed by subgroup, meta-regression, and sensitivity analyses. We conducted a Bootstrapped meta-analysis using 1,000 and 10,000 simulations to test the accuracy of the obtained results. The certainty of evidence was assessed by the GRADE approach. RESULTS: Our meta-analysis included 9 observational studies. The PCOS patients showed significantly higher NC values than the non-PCOS controls (SMD: 0.66, 95% CI: 0.41-0.91, p < 0.0001). In the bootstrap meta-analysis, the accuracy of the observed findings was proved (SMD = 0.66, 95% CI = 0.42-0.91) for the NC outcome. No publication bias was detected in the funnel plot analysis using Begg's and Egger's tests. The 95% prediction interval of 0.036-1.28 suggests that the true outcomes of the studies are generally in the same direction as the estimated average outcome. The sensitivity analysis provided the robustness of the outcome, and no single study was overly influential on the pooled estimate. CONCLUSION: This meta-analysis provides accurate evidence for significantly higher NC values in PCOS as compared to non-PCOS controls. There is no sufficient evidence on the diagnostic accuracy measures for NC in PCOS. Hence, further research on its diagnostic utility in PCOS is needed.

Anatomical variations in the course of spinal accessory nerve in the neck triangles: A descriptive study.

BACKGROUND: Spinal Accessory Nerve (SAN), which innervates the sternocleidomastoid (SCM) and trapezius muscles, is closely related to the internal jugular vein (IJV) in the anterior triangle of the neck and passes superficially in the posterior triangle. Injury to SAN is a major complication of level II neck dissection, leading to shoulder syndrome. The present study aims to assess the course and its relation to the SCM muscle and IJV in the Tamil ethnolinguistic groups in South India. METHODS AND MATERIALS: The anterior and posterior triangles of the neck were dissected in 28 formalin-fixed adult cadavers. The course of the SAN and the entry and exit points of SAN along the SCM muscle were assessed using the mastoid process as the reference. Recorded data was analyzed using SPSS software. RESULTS: The SAN was anteriorly related to the IJV in 58.73%, posteriorly in 37.5%, and pierced through the IJV in 3.57% of the specimens. The entry and exit points of SAN from the mastoid process were 37.86±7.26mm and 48.55±8.22mm, respectively. In 86.67% of the cases, the SAN traversed through the SCM muscle, and in 13.33%, it was deep to the SCM. CONCLUSION: The present study reports that the SAN is variable in its course, and relation to SCM and IJV. Knowledge about the variant anatomy of the SAN in the triangles of the neck is important and it aids surgeons to prevent iatrogenic injuries to SAN or IJV and enhance surgical safety in neck procedures.

Magnetic resonance imaging-based classification of the myodural bridge complex and its influencing factors.

Cerebrospinal fluid (CSF) circulation is considered the third circulation of the human body. Recently, some scholars have proposed the myodural bridge (MDB) as a novel power source for CSF flow. Moreover, the suboccipital muscles can exert a driving force on the CSF via the MDB. This hypothesis is directly supported by head rotation and nodding movements, which can affect CSF circulation. The MDB has been validated as a normal structure in humans and mammals. In addition, the fusion of MDB fibers of different origins that act in concert with each other forms the MDB complex (MDBC). The MDBC may be associated with several CSF disorder-related neurological disorders in clinical practice. Therefore, the morphology of the MDBC and its influencing factors must be determined. In this study, T2-weighted imaging sagittal images of the cervical region were analyzed retrospectively in 1085 patients, and magnetic resonance imaging (MRI) typing of the MDBC was performed according to the imaging features of the MDBC in the posterior atlanto-occipital interspace (PAOiS) and posterior atlanto-axial interspace (PAAiS). The effects of age and age-related degenerative changes in the cervical spine on MRI staging of the MDBC were also determined. The results revealed four MRI types of the MDBC: type A (no MDBC hyposignal shadow connected to the dura mater in either the PAOiS or PAAiS), type B (MDBC hyposignal shadow connected to the dura mater in the PAOiS only), type C (MDBC hyposignal shadow connected to the dura mater in the PAAiS only), and type D (MDBC hyposignal shadow connected to the dura mater in both the PAOiS and PAAiS). The influencing factors for the MDBC typing were age (group), degree of intervertebral space stenosis, dorsal osteophytosis, and degenerative changes in the cervical spine (P < 0.05). With increasing age (10-year interval), the incidence of type B MDBC markedly decreased, whereas that of type A MDBC increased considerably. With the deepening of the degree of intervertebral space stenosis, the incidence of type C MDBC increased significantly, whereas that of type A MDBC decreased. In the presence of dorsal osteophytosis, the incidence of type C and D MDBCs significantly decreased, whereas that of type A increased. In the presence of protrusion of the intervertebral disc, the incidence of type B, C, and D MDBCs increased markedly, whereas that of type A MDBC decreased considerably, with cervical degenerative changes combined with spinal canal stenosis. Moreover, the incidence of both type C and D MDBCs increased, whereas that of type A MDBC decreased. Based on the MRI signal characteristics of the dural side of the MDBC, four types of the MDBC were identified. MDBC typing varies dynamically according to population distribution, depending on age and cervical degeneration (degree of intervertebral space stenosis, vertebral dorsal osteophytosis formation, simple protrusion of intervertebral disc, and cervical degeneration changes combined with spinal canal stenosis, except for the degree of protrusion of the intervertebral disc and the degree of spinal canal stenosis); however, it is not influenced by sex.

Imaging of the Craniocervical Junction: A Pictorial Review.

The craniocervical junction (CCJ) is a complex anatomical structure comprising the occiput, the atlas, and the axis. The CCJ plays an important role in maintaining stability, providing protection, and supporting neurovascular structures. The CCJ can be affected by a wide range of congenital variants and traumatic, degenerative, inflammatory, and tumoral pathologies. This pictorial review the normal anatomy of the CCJ and presents the most common anatomical variants and pathologic conditions affecting the CCJ.

La importancia del conocimiento de la anatomía facial en armonización facial / The knowledge of facial anatomy in facial harmonization

La odontología argentina ha considerado reciente- mente la incorporación de armonización orofacial en odontología, acompañando los cambios que vienen sucediendo en el mundo con respecto a este tema. Países con especialización en armonización orofacial en odontología, como Brasil, 2019 o Venezuela, 2020, son muestra de ello. La evolución de la tecnología, junto con los cambios de paradigmas de la sociedad, ha cambiado aún el con- cepto de tratamiento desde la OMS. Actualmente bus- ca, como beneficio para los pacientes, el bienestar físico mental y social, no solo tratar o prevenir patologías. Acompañando estos conceptos las ciencias se adap- tan también a las necesidades de la población. El conocimiento de la anatomía facial también ha avanzado gracias a la tecnología y volumen de trabajos científicos desarrollados para conocer en profundidad cada una de las estructuras faciales y su relación entre ellas. Para ello ha sido fundamental la preparación actualizada de profesionales que traba- jan abordando tejidos blando de cara y cuello (AU)

Argentine dentistry has recently considered the incorporation of Orofacial Harmonization in Dentistry accompanying the changes that have been happening in the world regarding this issue, countries specializing in Orofacial Harmonization in Dentistry such as Brazil 2019 or Venezuela 2020 are proof of this. The evolution of technology together with the paradigm shifts of society has changed still the concept of treatment from the OMS Looking for a benefit for patients physical mental and social well-being and not only treat or prevent pathologies. Accompanying these concepts, the sciences also adapt to the needs of the population. Knowledge of facial anatomy has also advanced thanks to technology and volume of scientific works developed to know in depth each one of the structures facial features and their relationship between them, being essential the updated preparation of the professionals who work addressing soft tissues of the face and neck (AU)

An anatomical study of the suboccipital cavernous sinus and its relationship with the myodural bridge complex.

The suboccipital cavernous sinus (SCS) and the myodural bridge complex (MDBC) are both located in the suboccipital region. The SCS is regarded as a route for venous intracranial outflow and is often encountered during surgery. The MDBC consists of the suboccipital muscles, nuchal ligament, and myodural bridge and could be a power source for cerebrospinal fluid circulation. Intracranial pressure depends on intracranial blood volume and the cerebrospinal fluid. Since the SCS and MDBC have similar anatomical locations and functions, the aim of the present study was to reveal the relationships between them and the detailed anatomical characteristics of the SCS. The study involved gross dissection, histological staining, P45 plastination, and three-dimensional visualization techniques. The SCS consists of many small venous sinuses enclosed within a thin fibrous membrane that is strengthened by a fibrous arch closing the vertebral artery groove. The venous vessels are more abundant in the lateral and medial portions of the SCS than the middle portion. The middle and medial portions of the SCS are covered by the MDBC. Type I collagen fibers arranged in parallel and originating from the MDBC terminate on the SCS either directly or indirectly via the fibrous arch. The morphological features of SCS revealed in this research could serve as an anatomical basis for upper neck surgical procedures. There are parallel arrangements of type I collagen fibers between the MDBC and the SCS. The MDBC could change the blood volume in the SCS by pulling its wall during the head movement.

Appropriate neck circumference and waist-to-height ratio cut-off points as predictors of obesity and cardiovascular risk in adolescents.

OBJECTIVE: To determine neck circumference (NC) and waist-to-height ratio (WHtR) cut-off points as predictors of obesity and cardiovascular risk in adolescents. METHODS: Cross-sectional study developed with a subsample of 634 adolescents aged 18 and 19 years belonging to the third phase of the "RPS" cohort (Ribeirão Preto, Pelotas and São Luís) carried out in 2016. The area under the ROC curve (AUC) was identified to assess the predictive capacity of NC and WHtR in relation to the percentage of body fat (%BF), obtained by air displacement plethysmography (ADP), and the cardiovascular risk estimated by the Pathobiological Determinants of Atherosclerosis in Youth (PDAY). RESULTS: The prevalence of obesity by %BF was 7.6% in males and 39.4% in females (p-value <0.001), and the high PDAY risk was 13.8% and 10.9%, respectively. For males, NC cut-off point was 44.0 cm and the AUCs were 0.70 (95%CI 0.58-0.83) to predict obesity and 0.71 (95%CI 0.62-0.80) to predict high cardiovascular risk; for females, NC cut-off point was 40 cm and the AUCs were 0.75 (95%CI 0.69-0.80) and 0.63 (95%CI 0.53-0.73), respectively. WHtR cut-off point was 0.50 for both sexes; for males, the AUCs to predict obesity and high risk according to PDAY were 0.90 (95%CI 0.80-0.99) and 0.73 (95%CI 0.63-0.82), respectively; for females, they were 0.87 (95%CI 0.83-0.90) and 0.55 (95%CI 0.45-0.65), respectively. CONCLUSION: WHtR and NC are good discriminators to assess obesity and cardiovascular risk in adolescents, especially in males.

Quantifying research on anatomical structures, a potential new metric for assessing clinical relevance.

Human anatomy remains an integral part of medical education, and recent studies have documented an emerging consensus on the key anatomical learning objectives for physicians and other health professionals in training, both at the graduate and postgraduate levels. Despite this progress, less attention has been given to assessing the clinical relevance of individual anatomical structures, and which structures students should master to achieve these learning objectives. In this study we hypothesized that published research involving individual anatomical structures is largely driven by the clinical relevance of these structures, and that tabulating the number of such publications can provide an up-to-date, evolving metric of clinical relevance. To test this hypothesis, we developed a semi-automated search routine that uses the PubMed database to quantify the publication frequency of anatomical structures and compared that to a previous study that assessed the importance of structures of the head and neck using the Delphi method, a formal procedure of generating expert consensus. Using our new approach, we were able to rank the research intensity of 2182 anatomical structures included in Grant's Dissector, a widely used textbook for anatomical dissection. Furthermore, a sample of these PubMed-derived ranks had a highly significant, positive correlation with ranks derived from a consensus of experts. Similar results were obtained when PubMed searches were restricted to journals that focus on applying knowledge in a clinical setting. Our study provides a potential new tool for anatomical educators who are aligning their basic science curricula with the clinical knowledge expected of medical graduates.