Anatomical Markers Research Articles

Changes in facial soft tissue support with and without a maxillary labial flange.

To quantify facial esthetic outcomes of prosthetic upper lip support in both full animation and repose for patients with an existing implant-supported fixed complete dental prosthesis (ISFCDP). Twenty patients had a removable prosthetic labial flange fabricated for their existing maxillary prosthesis. The 3dMDface system was used to capture video sets of each patient going from repose to high smile with and without the labial flange. A single frame representing high smile and repose was selected from each video. Five facial anatomic markers and 21 individual points on the upper lip were evaluated for both image sets using quantitative photometric analysis. To provide a qualitative assessment, the same images were shown to dentists, laypeople, and the research subjects (patients) to determine which they found to be more esthetically pleasing, or if there was no difference. Quantitative data was evaluated using paired t-tests. The two-dimensional analysis showed a difference with and without a labial flange for lip projection and lip thickness. Additionally, 13 out of 21 landmarks in the three-dimensional analysis showed differences when comparing the superimposed labial flange and no flange linear difference values between high smile and repose. Survey results showed that research subjects (54.41%), dentists (51.50%), and laypeople (44.50%), all preferred labial flange versus no flange photos or were not able to tell a difference. Qualitative and quantitative results suggest that a prosthetic labial flange has an impact on upper lip support. Clinicians should consider lip support both in full animation and repose when treatment planning for the maxillary ISFCDP.

Authentication and Quality Control of the Brazilian Traditional Herb 'Carquejas' (Baccharis Species) Using Morpho-Anatomy and Microscopy.

This research investigates the morpho-anatomical characteristics of seven Baccharis species, namely B. articulata, B. milleflora, B. myriocephala, B. pentaptera, B. riograndensis, B. sagittalis and B. trimera. Commonly called carquejas, these species have aerial photosynthetic winged stems known as cladodes and are widely used traditionally to treat digestive and diuretic disorders. This study aimed to characterize these commonly misidentified species using morphological and microscopic techniques, including light and scanning electron microscopy coupled with energy-dispersive X-ray spectroscopy. Trichomes, the presence or absence of oil bodies, and a subepidermal collenchyma layer at the wing edge were identified as primary anatomical markers that can help differentiate the studied species.

Automated Preoperative Planning Algorithm for Mandibular Angle Osteotomy Based on Anatomical Landmarks Detection: A Retrospective Study.

The aim of the study was to develop and evaluate an automated preoperative planning algorithm based on anatomical landmark point recognition for enhancing the efficiency and intelligence of preoperative planning for mandibular angle osteotomy. A retrospective cohort of 34 patients underwent preoperative planning with this algorithm. The present algorithm was developed using a method based on anatomical marker point recognition. The efficiency, symmetry, and safety of the automated preoperative planning and esthetics were statistically analyzed by paired t test and χ2 test. The results showed that the automated planning algorithm was able to achieve a great improvement in preoperative planning efficiency as well as safety and symmetry. A prospective case report of 2 patients is then reported, illustrating the safety and esthetics of the algorithm with 1-year postoperative follow-up and postoperative esthetic scores. This algorithm can help to improve the efficiency of preoperative planning for surgeons while ensuring safety and esthetics and can be further applied to other craniomaxillofacial personalized design surgeries in the preoperative design in the future.

A Causal Inference Approach to Mediation Analysis in Vitreomacular Traction: How Much Does Traction Resolution Mediate Functional Outcomes?

Modern mediation analysis techniques supplement the primary intention-to-treat analysis with the aim to shed light onto the treatment mechanism. We investigate to what extent the anatomic marker vitreomacular adhesion resolution (VMAR) mediates vision benefits, comparing ocriplasmin vs. a sham regimen. A causal mediation analysis is applied to randomized trial data including 218 participants with vitreomacular traction. Logistic regression models are used to estimate the total treatment effect (TTE) on binary outcomes. Outcomes, assessed at month 24, included visual acuity improvement (VA-I): ≥2-line increase in VA; visual function questionnaire improvement (VFQ-I): ≥5-point increase in the 25-item visual function questionnaire composite score (VFQ-25cs); visual function improvement (VF-I): defined as either a VA-I or a clinically meaningful improvement in the VFQ-25cs. Quantity of interest is the breakdown of TTE into an indirect (through VMAR) and direct effect to estimate the extent to which the TTE is transmitted through the mediating variable (VMAR) vs. other pathways. Causal effects are expressed as risk differences. Indirect effects for VFQ-I, VA-I, and VF-I are 5.7%, 11.8%, and 5.2%, respectively, representing the increase in the probability of a vision improvement if VMAR status were changed for each participant to the extent that it is affected by ocriplasmin. The direct effects are 8.3%, 12.1%, and 24.1% respectively, capturing the effect of treatment on the probability of a vision improvement if ocriplasmin left each participant's VMAR status unchanged. The relative treatment effect of ocriplasmin on the functional outcome VA-I is to a large extent the result of its effect on VMAR, while an improvement in the patient-reported outcomes VFQ-I or VF-I was only partially mediated by VMAR.

Evaluation of Digit Ratios in Youth With Polycystic Ovary Syndrome.

Polycystic ovary syndrome (PCOS) is a common syndrome often observed during adolescence, characterized by ovulatory dysfunction and hyperandrogenism. It is determined that, when female fetuses are exposed to high levels of androgens, it increases their likelihood of developing PCOS in later ages. The 2D:4D digit ratio, which measures the length of the index finger compared to the ring finger, is a precise anatomical indicator of the degree of prenatal androgen exposure. Higher digit ratios in individuals have been associated with outcomes typically attributed to females. In the adolescent age group, the relationship between PCOS and androgen exposure during the antenatal period is not clear. The study was aimed to evaluate digit ratios in adolescents with PCOS. The study included 38 adolescent girls with PCOS, and 40 healthy adolescent girls were selected as the control group. The digit ratio (2D:4D) was evaluated by digital calipers, and the digit ratios of the patient and control groups were compared. The mean age in the PCOS group was 15.99±1.18 years, while the control group had a mean age of 16.02±1.06 years. The right-hand 2D:4D digit ratio was significantly lower in the PCOS group (0.93±0.02) compared to the control group (1.00±0.01, p<0.001). Similarly, the left-hand 2D:4D digit ratio was also lower in the PCOS group (0.98±0.03) compared to the control group (1.00±0.01, p<0.001). There was a moderate negative correlation between the left-hand 2D:4D ratio and the modified Ferriman-Gallwey score (mFGS) (r=0.53, p=0.01). Nevertheless, there was not a significant association found between the 2D:4D ratio of the right hand and mFGS. This study demonstrates that PCOS patients have significantly lower both-hand 2D:4D ratios than healthy controls, suggesting prenatal androgen exposure. Recognizing anatomic markers in adolescence may predict the development of PCOS. The findings align with previous research linking low digit ratios to androgen exposure and various reproductive outcomes.

Design and application of a novel 3D printing digital navigation template for cubitus varus deformity in children.

This study was aimed to assess the feasibility and efficacy of 3D printing digital template for treatment of cubitus varus deformity. 32 patients who underwent lateral closing osteotomy were evaluated between January 2018 and January 2020 in this retrospective study. Navigation templates were used in 17 cases, while conventional surgery in 15 cases. The carrying angles before and after surgery, operation time and elbow joint function were compared. Navigation templates matched well with the anatomical markers of the lateral humerus. More accurate osteotomy degrees, shorter operation time and less radiation exposure were achieved in the navigation template group (p < 0.05). At the last follow-up time, significant difference was found based on the Bellemore criteria (p = 0.0288). The novel navigation template can shorten operation time, improve the lateral closing osteotomy accuracy and improve postoperative elbow joint function.

Assessment of predictive value of thyromental height in predicting difficult laryngoscopy compared with Mallampati, and thyromental distance among surgical patient who will take general anesthesia at selected governmental hospital cross-sectional study: Ethiopia, 2022.

Anesthesiologists must always perform a preoperative airway examination to identify individuals who will have challenging laryngoscopy. In an effort to identify the most accurate airway predictor, numerous authors have evaluated a number of predictive assays. Thyromental height test (TMHT), a new airway predictor, has recently been demonstrated to have good predictive value in determining difficult airways. This study's main objective was to assess the diagnostic effectiveness of the TMHT and compare it to other known airway predictors, such as the modified Mallampati test (MMT) and the thyromental distance (TMD). To assess the predictive value of TMHT in predicting difficult laryngoscopy compared to modified MMT and TMD among patients who will take general anesthesia. In this prospective, observational study, which took place from March 2021 to May 2021, 247 people of either sex who were older than 18 but not more than 65 and scheduled for elective surgery under general anesthesia participated. The receiver operating characteristic (ROC) curve was used to identify the proper cut-off values for TMHT, and the Fisher exact test was used to calculate the correlation. Incidence of Difficult laryngoscopy was 13.4%. For TMHT the cut-off values were 4.9cm and it had a sensitivity of 78.8%, a specificity of 89.7%, a positive predictive value (PPV) of 54.2%, and a negative predictive value (NPV) of 96.5%, respectively. When compared to other parameters, like TMD, and MMT. TMHT had the highest sensitivity, specificity, PPV, and NPV. (P<0.000). Of all the airway assessments, the TMHT had the highest accuracy and odds ratio for predicting difficult laryngoscopy with the highest odds ratio and accuracy. TMHT has to be validated in broader patient groups because it appears to be a possible single anatomical marker for predicting the likelihood of a difficult laryngoscopy. It needs more research because it isn't assessed in pediatrics and pregnant women.

Smartphone videos-driven musculoskeletal multibody dynamics modelling workflow to estimate the lower limb joint contact forces and ground reaction forces.

The estimation of joint contact forces in musculoskeletal multibody dynamics models typically requires the use of expensive and time-consuming technologies, such as reflective marker-based motion capture (Mocap) system. In this study, we aim to propose a more accessible and cost-effective solution that utilizes the dual smartphone videos (SPV)-driven musculoskeletal multibody dynamics modeling workflow to estimate the lower limb mechanics. Twelve participants were recruited to collect marker trajectory data, force plate data, and motion videos during walking and running. The smartphone videos were initially analyzed using the OpenCap platform to identify key joint points and anatomical markers. The markers were used as inputs for the musculoskeletal multibody dynamics model to calculate the lower limb joint kinematics, joint contact forces, and ground reaction forces, which were then evaluated by the Mocap-based workflow. The root mean square error (RMSE), mean absolute deviation (MAD), and Pearson correlation coefficient (ρ) were adopted to evaluate the results. Excellent or strong Pearson correlations were observed in most lower limb joint angles (ρ = 0.74 ~ 0.94). The averaged MADs and RMSEs for the joint angles were 1.93 ~ 6.56° and 2.14 ~ 7.08°, respectively. Excellent or strong Pearson correlations were observed in most lower limb joint contact forces and ground reaction forces (ρ = 0.78 ~ 0.92). The averaged MADs and RMSEs for the joint lower limb joint contact forces were 0.18 ~ 1.07 bodyweight (BW) and 0.28 ~ 1.32 BW, respectively. Overall, the proposed smartphone video-driven musculoskeletal multibody dynamics simulation workflow demonstrated reliable accuracy in predicting lower limb mechanics and ground reaction forces, which has the potential to expedite gait dynamics analysis in a clinical setting.

Marker Data Enhancement For Markerless Motion Capture.

Human pose estimation models can measure movement from videos at a large scale and low cost; however, open-source pose estimation models typically detect only sparse keypoints, which leads to inaccurate joint kinematics. OpenCap, a freely available service for researchers to measure movement from videos, addresses this issue using a deep learning model-the marker enhancer-that transforms sparse keypoints into dense anatomical markers. However, OpenCap performs poorly on movements not included in the training data. Here, we create a much larger and more diverse training dataset and develop a more accurate and generalizable marker enhancer. We compiled marker-based motion capture data from 1176 subjects and synthesized 1433 hours of keypoints and anatomical markers to train the marker enhancer. We evaluated its accuracy in computing kinematics using both benchmark movement videos and synthetic data representing unseen, diverse movements. The marker enhancer improved kinematic accuracy on benchmark movements (mean error: 4.1°, max: 8.7°) compared to using video keypoints (mean: 9.6°, max: 43.1°) and OpenCap's original enhancer (mean: 5.3°, max: 11.5°). It also better generalized to unseen, diverse movements (mean: 4.1°, max: 6.7°) than OpenCap's original enhancer (mean: 40.4°, max: 252.0°). Our marker enhancer demonstrates both accuracy and generalizability across diverse movements. We integrated the marker enhancer into OpenCap, thereby offering its thousands of users more accurate measurements across a broader range of movements.

Assessment of variations in the nasopalatine canal on CBCT: considerations from an anatomical point of view.

The nasopalatine canal (NPC) is one of the most significant anatomical markers in the anterior maxillary region. Its location is quite important, especially for implant placement. Therefore, the purpose of this study was to use cone-beam computed tomography (CBCT) to evaluate the morphology, size, and anatomic variations of the NPC. A total of 150 individual CBCT images were assessed in various sections to evaluate the dimensions, morphology, and extent of the NPC. Reformatted sagittal images were chosen to classify the shape and course of the canal. The Student's t-test, the χ² test, and Pearson correlation coefficients were used. The NPC was longer in males than in females, and the mediolateral diameter of the canal was greater in older adults. In sagittal sections, the canal predominantly exhibits a cylindrical shape, while a spindle shape is the least common. In coronal sections, a single shape is most frequently observed, with a Y-shape being the least common. Regarding the orientation of the canal, slanted canals are more prevalent, whereas vertically curved canals are rare. Typically, 2 canal openings are observed, with 4 openings being the least common. The current study highlights the challenges associated with identifying the anatomical appearance and variations of the NPC. Consequently, possessing a thorough understanding of this anatomy is essential before undertaking any surgical procedures, such as implant placement. This knowledge helps prevent complications such as nerve injury-related loss of sensation, bleeding due to blood vessel injury, and the development of a nasopalatine duct cyst following trauma to the canal during surgery.

Pelvic Palpatory Tests in Manual Therapy and Osteopathy: A Critical Review of the Literature and Suggestions for New Research.

Manual therapists apply physical interventions to the entire structure of the body to promote healing, prevent pathologies, and improve patient health. In osteopathic practice, palpatory evaluation is considered a fundamental clinical practice requirement for identifying somatic dysfunction. Most of the articles published in this area have failed to demonstrate a level of reproducibility that supports palpation in evidence-based clinical practice. When considering the poor reliability of the palpatory tests highlighted in the literature, a discrepancy is noted with what is known about the tactile sensitivity of human hands. For static touch, the minimum size that can be detected, in the absence of applied movement or vibration, is approximately 0.2 mm. Yet, it seems that this high level of precision is insufficient to ensure reliability in the tests used to evaluate osteopathic somatic dysfunction. The purpose that underscores this article is to determine how these two contradictory elements, high sensitivity and low reliability, can be present in palpatory tests. The article reports the literature findings regarding palpatory tests of pelvic, which is an important structure for clinical purposes. Additionally, a critical review of how these studies were conducted is provided to identify any elements that may justify the obtained results. Following recent accredited guidelines present in the literature, we propose suggestions on vision training methods, manual perception refinement training, the search for anatomical markers, and the position of the examiner in relation to the examineethat may be useful for future studies on the topic covered by the article.

In vivo non-contact regions of proximal scaphoid in six extreme wrist positions

IntroductionFractures of the scaphoid are the most common carpal injuries, account for 80-90% of all carpal fractures. 5-15% nonunion of scaphoid fractures were reported even with adequate primary treatment, which probably progresses to osteoarthritic changes several decades later. Researches regarding to scaphoid physiological characteristic in vitro and in vivo and kinds of trials in clinical practice are being kept on going, which contribute much to our clinical practice. With the advancing wrist arthroscopy, 3D-print patient-specific drill guide, and intraoperative fluoroscopic guidance, dorsal approach (mini-invasive and percutaneous technique) is being popular, through which we can implant the screw in good coincidence with biomechanics and with less disturbing tenuous blood supply of the scaphoid. Investigating the noncontact area of the dorsal proximal scaphoid in different wrist positions can facilitate preoperatively estimating insert point of the screw.Materials and methodsEight volunteers were recruited to accept CT scans in six extreme wrist positions. The images of DICOM mode were imput into the Mimics analytical system, the segmented scaphoid, lunate and radius were exported in mode of ASCII STL and were opened in the software of Geomagic studio. We created four planes based on anatomic markers on the surface of the radius and scaphoid to confine the proximal scaphoid to form the so-called non-contact regions. We measured and compared the areas in six targeted positions.ResultsAmidst six extreme wrist positions, area of the non-contact region in extreme dorsal extension (59.81 ± 26.46 mm2) was significantly the smallest, and it in extreme palmar flexion significantly was largest (170.51 ± 30.44 mm2). The non-contact regions increased in order of dorsal extension, supination, ulnar deviation, radial deviation, pronation and palmar flexion. As for two-group comparison, the non-contact region showed significantly larger (p < 0.05) in palmar flexion than the others except for in pronation individually, and in radial deviation (p < 0.05) than in dorsal extension.ConclusionsSufficient space was available for the screw started from the dorsal approach despite the wrist positions.

Evaluation of Sexual Dimorphism Using Condylar and Coronoid Mandibular Parameters in Orthopantomograms: A Pilot Study.

Background Gender determination is critical to forensic science and medico-legal applications. Given that it is the most dimorphic bone in the skull and is frequently found intact, the mandibular bone may be extremely important in determining gender. Orthopantomograms (OPGs) are quite helpful in accurately estimating age and sex in this regard. It is a laborious task for forensics to determine the gender of victims of mass casualties, natural disasters, and severely dismembered bodies. The mandible, which is susceptible to development spurts, has a high degree of accuracy for determining sex. Aim This study aims to evaluate the potential use of coronoid height and condylar height as reliable anatomical markers for determining gender. Materials and methods In this study, 100 samples were used as study samples, 50 of which were male and 50 of which were female, in the age group of 20-30 years. The OPGs were obtained using a Planmeca Promax Scara 3 Digital OPG Machine (Planmeca, Helsinki, Finland), with settings of 70 kVp, 8 mA for 0.9 seconds, ensuring a 1:1 ratio. The images were then transferred to Planmeca Romexis® Viewer Software, Version 6.0 (Planmeca Oy, Helsinki, Finland) for measurement recording. Results Descriptive statistical analysis was done for this study and discriminant analysis was also done to create a population-specific formula. Results showed that the standard mean error for males concerning condylar height was 2.3 and coronoid height was 0.7. The standard mean error for females by condylar height was 1.6 and coronoid height was 0.6. The p-value was significant for coronoid height in both males and females. The p-value was not clinically significant for condylar height in both males and females. Conclusion The study's findings indicate that a larger mandibular angle is advantageous for gender assessment and helps with gender dimorphism. Out of both the parameters evaluated, coronoid height has shown statistical significance in both males and females. Hence, the study concludes that the parameter, coronoid height can be utilized to assess the gender of an individual.

Invasive electrochemical impedance spectroscopy with phase delay for experimental atherosclerosis phenotyping.

Distinguishing quiescent from rupture-prone atherosclerotic lesions has significant translational and clinical implications. Electrochemical impedance spectroscopy (EIS) characterizes biological tissues by assessing impedance and phase delay responses to alternating current at multiple frequencies. We evaluated invasive 6-point stretchable EIS sensors over a spectrum of experimental atherosclerosis and compared results with intravascular ultrasound (IVUS), molecular positron emission tomography (PET) imaging, and histology. Male New Zealand White rabbits (n = 16) were placed on a high-fat diet, with or without endothelial denudation via balloon injury of the infrarenal abdominal aorta. Rabbits underwent invivo micro-PET imaging of the abdominal aorta with 68Ga-DOTATATE, 18F-NaF, and 18F-FDG, followed by invasive interrogation via IVUS and EIS. Background signal-corrected values of impedance and phase delay were determined. Abdominal aortic samples were collected for histology. Analyses were performed blindly. EIS impedance was associated with markers of plaque activity including macrophage infiltration (r = .813, p = .008) and macrophage/smooth muscle cell (SMC) ratio (r = .813, p = .026). Moreover, EIS phase delay correlated with anatomic markers of plaque burden, namely intima/media ratio (r = .883, p = .004) and %stenosis (r = .901, p = .002), similar to IVUS. 68Ga-DOTATATE correlated with intimal macrophage infiltration (r = .861, p = .003) and macrophage/SMC ratio (r = .831, p = .021), 18F-NaF with SMC infiltration (r = -.842, p = .018), and 18F-FDG correlated with macrophage/SMC ratio (r = .787, p = .036). EIS with phase delay integrates key atherosclerosis features that otherwise require multiple complementary invasive and non-invasive imaging approaches to capture. These findings indicate the potential of invasive EIS to comprehensively evaluate human coronary artery disease.

Radiographic Recognition of Mental Nerve for Secured Dental Implant Placement by Cone-Beam Computed Tomography in Mosul City Population.

The study aims to estimate precisely the different levels of mental loop and foramina in the Mosul population of Nineveh governorate in Iraq. It is a cross-sectional study of a previously saved database in the cone-beam computed tomography device. The study sample was 357 patients selected randomly from the database of patients at the Oral Radiology Unit at the Maxillofacial Department in Al-Salam Teaching Hospital. The study variables are mental foramen (MF) position, shape, radiograph appearance, and mental loop presence and direction. The results show that the age group from 19 to 30 years shows the highest percentage (40.1%). Females show more than half of the cases (59.7%). The MF position's highest percentage is shown in 2 areas with the slight differences. These are the long axis of first premolar and the area between first premolar and second premolar (42.6%, 40.9). According to shape variation round shapes are the uppermost percent (53.8%). More than 60% of cases (66.1%) show continuity with the inferior alveolar canal and 50% show no loop presence, and the mental nerve leaves the foramen in a perpendicular direction. In conclusion localization of the MF, nerve, and its loop precisely in both horizontal and vertical directions, both hard and soft tissues in a continuous view. Before arranging any surgical procedure, anatomic markers are crucial. To reduce the danger of harm to the foramen region, the authors thus advised cone-beam computed tomography before scheduling implant surgery, particularly in the mental region of the jaw.

Second to fourth digit ratio (2D:4D) as the 'anatomical marker' and reproductive 'hormonal fingerprint' in the occurrence dental plaque accumulation.

Digit ratio (2D:4D), as endocrine fingerprint, can indicate prenatal androgen exposure. It serves as an anatomical marker for various systemic diseases and a few studies relating it to oral health. The present study aims to evaluate the association between digit ratio and susceptibility to dental plaque formation. The study was conducted on young adults aged between 18 and 25 years. Digit ratio and reproductive hormones were measured; dental plaque score and gingival index (GI) were recorded. Data were analysed using the MedCalc. v.20. Male and female participants were categorized into two groups based on their digit ratios being either above or below the calculated average (0.99 for females, 0.98 for males). Those with a digit ratio below the average had a significantly higher mean dental plaque score (p < 0.0001) than those with ratios at or above the average. However, there was no significant difference in the GI between the two groups. Reproductive hormone profiles varied significantly between the higher and lower digit ratio groups for both sexes. Digit ratio may find potential to be used as an anatomical marker to identify the susceptibility to dental plaque build-up.

Reconstruction of occluded pelvis markers during marker-based motion capture with industrial exoskeletons

Industrial back support exoskeletons are a promising solution to alleviate lumbar musculoskeletal strain. Due to the complexity of spinal loading, evaluation of EMG data alone has been considered insufficient to assess their support effects, and complementary kinematic and dynamic data are required. However, the acquisition of marker-based kinematics is challenging with exoskeletons, as anatomical reference points, particularly on the pelvis, are occluded by exoskeleton structures. The aim of this study was therefore to develop and validate a method to reliably reconstruct the occluded pelvic markers. The movement data of six subjects, for whom pelvic markers could be placed while wearing an exoskeleton, were used to test the reconstructions and compare them to anatomical landmarks during lifting, holding and walking. Two separate approaches were used for the reconstruction. One used a reference coordinate system based on only exoskeleton markers (EXO), as has been suggested in the literature, while our proposed method adds a technical marker in the lumbar region (LUMB) to compensate for any shifting between exoskeleton and pelvis. Reconstruction with EXO yielded on average an absolute linear deviation of 54 mm ± 16 mm (mean ± 1SD) compared to anatomical markers. The additional marker in LUMB reduced mean deviations to 14 mm ± 7 mm (mean ± 1SD). Both methods were compared to reference values from the literature for expected variances due to marker placement and soft tissue artifacts. For LUMB 99% of reconstructions were within the defined threshold of 24 mm ±9 mm while for EXO 91% were outside.

Anatomical Markers Associated With the Presence of Intracranial Aneurysms in Individuals Screened for Aneurysms

Background Hemodynamic stress is linked to the development of intracranial aneurysms (IAs) and may be influenced by anatomic variation of intracranial arteries. We assessed diameters and bifurcation angles of intracranial arteries forming the circle of Willis in a cohort of individuals screened for the presence of IAs. Methods Individuals with and without IAs identified at screening with magnetic resonance angiography were compared. Diameters and bifurcation angles of the following arteries were measured using semiautomatic methods: A1 and A2 segments of the anterior cerebral artery, M1 and M2 segments of the middle cerebral artery, P1 segments of the posterior cerebral artery, posterior communicating artery (Pcom), internal carotid artery, vertebral artery, and basilar artery. We employed univariate general linear models to assess group differences. This included subgroup comparisons between individuals with IAs at specific locations and matched controls, and comparisons on group level between individuals with and without IAs, corrected for age and sex. Results In 94 of the 1049 individuals (9.0%) included, IAs were detected. Individuals with middle cerebral artery IAs had wider ipsilateral M2–M2 bifurcation angles compared with controls (121±25° versus 97±19°; P &lt;0.01). Individuals with anterior communicating artery IAs showed smaller angles for the A1–A2 bifurcation (106±16° versus 120±17°; P = 0.02), while those with Pcom IAs had wider Pcom–C7 bifurcation angles (147±14° versus 127±17°; P = 0.02) and smaller diameters below the ipsilateral internal carotid artery top (2.86±0.36 mm versus 3.10±0.33 mm; P = 0.03) compared with controls. Conclusion We found associations between wider M2–M2 bifurcation angles or narrower A1–A2 bifurcation angles and IA presence, consistent with prior literature. Moreover, we uncovered previously unexplored associations, including wider Pcom–C7 bifurcation angles and smaller internal carotid artery diameters in individuals with Pcom IAs. Future research should explore the potential of these markers in predicting IAs in at‐risk populations during follow‐up screenings.

Cochlear implantation through retro-facial approach with congenital microtia malformation with facial nerve deformity: a case report

The difficulty of cochlear implantation in patients with congenital microtia is usually increased due to the vague anatomical marks and facial nerve malformation. The common types of facial nerve malformation include facial nerve bony cover loss, aberrant position, and bifurcation malformation. Bifurcation malformation may obscure the oval window, press against stapes, and bifurcate in the vestibular window while obscuring the round window. It is important to correctly identify the facial nerve and choose a reasonable surgical approach to avoid postoperative complications. This article describes a case of profound sensorineural hearing loss due to facial nerve malformation in our institution. The patient underwent cochlear implantation through the retro-facial approach. There was no facial nerve injury or dysfunction symptoms such as facial paralysis and hemifacial spasm 2 years after the operation, and the cochlear implant works well. The score of the categories of the auditory performance（CAP） questionnaire was 7, and the score of the speech intelligibility rating（SIR） questionnaire was 4. When the round window cannot be exposed through the facial recess approach during surgery, the retro-facial approach is a feasible method. To avoid facial nerve injury, a thin-section CT of the temporal bone should be performed before the middle and inner ear surgery for patients with facial nerve malformation, and the intraoperative facial nerve monitor should be used to clarify the course of the facial nerve to avoid injury.

Mandibular Reconsctruction using Double Barrel Costal Non Vascularized Bone Graft with Stereolitographic Three Dimensional Printed Models

Surgeons face problems in reconstructing the facial profile after mandibular resection aesthetically and practically. The stereolithographic method was used in the 3D virtual reconstruction program for preoperative planning. This study aims to document the use of 3D printed models in the reconstruction of mandibular ameloblastoma patients under general anesthesia after segmental resection with non-vascularized autogenous costal bone grafts arranged in double-barrel sequence at Airlangga University Hospital, Surabaya, Indonesia. A single ameloblastoma from an anterior mandibular patient undergoing segmental mandibular resection is reported here. Autodesk Fusion 360 was used preoperatively to simulate anatomical markers, surgical margins, and plate morphology to create 3D models used for plate pre-bending. The graft used for reconstruction is a non-vascularized autogenous costal bone graft which is then stacked with an anteroposterior double-barrel. The patient did not show any severe complications associated with the surgery. Stereolithographic helps determine the extent of the lesion in the mandible. 3D printing improves graft viability by enabling optimal planning of the template, reduces operating room time by pre-bent screw plates, and increases procedural precision. The photo was taken a long time to process using virtual reconstruction software, but it put the surgeon at ease.