Detailed Anatomic Assessment Research Articles

Erosion of the temporal bone by vestibular schwannoma: morphometrics and predictive modeling.

To perform a comprehensive morphometric analysis of vestibular schwannomas (VS) using multimodal imaging, focusing on the relationship between tumor characteristics and internal acoustic canal (IAC) changes. We analyzed a cohort of patients undergoing radiosurgery for VS, utilizing high-definition MRI and bone CT for detailed anatomical assessment. Image co-registration and fusion techniques were employed to examine VS and IAC dimensions. Advanced statistical methods, including logistic regression, were applied to identify patterns of IAC dilation and establish predictive indicators for these morphological changes. The study included 659 patients (51.1% female, mean age 56.37years) with evenly distributed tumor lateralization. Koos grades were I (22.9%), II (29.9%), III (38.2%), IVa (8.9%), and IVb (0.3%). Most tumors (90.9%) extended both inside and outside the IAC. Ipsilateral IAC (IIAC) dimensions were significantly larger than contralateral, with IIAC volume 49% greater (p < .0001). Higher Koos grades correlated with increased intra-canalicular lesion volume (icLV), which was strongly associated with IIAC size. Logistic regression identified icLV as the strongest predictor of IIAC dilation (AUC = 0.7674, threshold = 137.52 mm3). The icLV appears central to the pathophysiological development of VS and its impact on IAC anatomy. While limited by a selective patient base and static imaging data, these findings enhance the understanding of VS-IAC interactions, offering insights for improved clinical management and further research.

Comparison of the Image Quality of Turbo Spin Echo and Echo-Planar Diffusion-Weighted Imaging of the Head and Neck Region.

Magnetic resonance imaging (MRI) of the head and neck region is notably challenging due to the complex anatomy and the critical need for high-resolution imaging to accurately diagnose various pathologies. The two prominent MRI techniques used in this context are turbo spin echo (TSE) and echo-planar diffusion-weighted imaging (EP-DWI). TSE is recognized for providing high-resolution anatomical images, whereas EP-DWI offers functional imaging that highlights the diffusion of water molecules, essential for detecting early pathological changes. This study aims to compare the image quality of TSE and EP-DWI in the head and neck region to assess their diagnostic efficacy and clinical utility. This retrospective study was conducted at Saveetha Medical College and Hospital over six months. A total of 100 patients (50 males and 50 females, aged 18-65 years) with various head and neck pathologies were included. Patients underwent both TSE and EP-DWI sequences using a Philips MULTIVA 1.5 T scanner. Image quality was assessed based on signal-to-noise ratio (SNR), contrast-to-noise ratio (CNR), artifact presence, and lesion detection. Two experienced radiologists independently reviewed the images, with inter-observer agreement calculated using Cohen's kappa coefficient. The mean SNR for TSE was significantly higher than EP-DWI (45.2 vs. 28.7, p<0.01), indicating superior image clarity and detail in TSE images. TSE demonstrated a higher mean CNR compared to EP-DWI (25.4 vs. 15.8, p<0.01), suggesting better differentiation between different tissue types and pathologies. Artifacts were more frequent in EP-DWI images (45% vs. 15%), with motion artifacts being the most common. TSE detected more lesions (120 vs. 95), with more precise delineation of lesions. The inter-observer agreement was excellent for both TSE and EP-DWI, with kappa values of 0.85 and 0.80, respectively. TSE MRI provides superior image quality compared to EP-DWI for evaluating the head and neck region. The enhanced SNR and CNR in TSE images result in clearer and more detailed visualizations of anatomical structures and pathological changes, with fewer artifacts. While EP-DWI is valuable for functional imaging, its role should be complementary to TSE. The study suggests that TSE should be the preferred modality for detailed anatomical assessment in the head and neck region. Further studies with larger sample sizes and advanced imaging techniques may provide additional insights into optimizing MRI protocols for head and neck imaging.

Nerve enlargement in patients with Noonan syndrome: A retrospective cohort study.

Noonan syndrome (NS) is an autosomal dominant condition characterized by facial dysmorphism, congenital heart disease, development delay, growth retardation and lymphatic disease. It is caused by germline pathogenic variants in genes encoding proteins in the Ras/mitogen-activated protein kinase signaling pathway. Nerve enlargement is not generally considered as a feature of NS, although some cases have been reported. High-resolution nerve ultrasound enables detailed anatomical assessment of peripheral nerves and can show enlarged nerves. This retrospective cohort study aims to describe the sonographic findings of patients with NS performed during a 1-year time period. Data on the degree of enlargement, the relation to increasing age, pain in extremities, genotype on the gene level and clinical features were collected. Twenty-nine of 93 patients visiting the NS Center of Expertise of the Radboud University Medical Center Nijmegen underwent high-resolution ultrasound. In 24 patients (83%) nerve enlargement was found. Most of them experienced pain. We observed a weak correlation with increasing age and the degree of nerve enlargement but no association with pain, genotype at the gene level or clinical features. This study shows that patients with NS have a high predisposition for sonographic nerve enlargement and that the majority experience pain.

Anatomical and optical origins of negative dysphotopsia

Negative dysphotopsia (ND) is a complaint after, an otherwise uneventful, cataract surgery with intraocular lens (IOL) implantation. It is generally described as a shadow in the temporal peripheral visual field. Approximately 3% of the patients suffer from this condition and complaints range from mild visual field defects to a significant loss of peripheral vision that disturbs daily life. Originally, this condition was poorly understood as conventional ophthalmic techniques are not designed for a comprehensive evaluation of the peripheral vision. In the last years, however, a combination of dedicated anatomical measurements and optical ray tracing simulations have revealed the cause of ND and proposed different treatments.In this presentation the basic principles of ray tracing of the eye will be presented, followed by the main results of the ESCRS vRESPOND study. In this study, a detailed anatomical assessment of the pseudophakic population with and without ND was made. The distinct differences between both groups, such as a smaller (p = &lt;0.01) and more decentered (p &lt; 0.01) pupil and an increased temporal‐tilted iris (p &lt; 0.01), will be discussed. Interestingly, high‐resolution ocular MRI revealed that the in‐the‐bag IOL position and retinal shape did not differ significantly between both groups. The impact of these differences on the patient's peripheral vision will be shown through ray tracing simulations. First the optical origin of the shadow, caused by light rays missing the IOL, will be presented, followed by a quantitative analysis of the effect the different anatomical and IOL‐design parameters on the severity of this shadow. At the end of the presentation, the optical rationale behind some of the treatments of ND will be discussed.

Morphological analysis of the hypoglossal canal and its relationship with surrounding anatomical structures

Aim: The aim of this study was to investigate the hypoglossal canal morphologically and to emphasize the importance of its relation to the adjacent anatomical structures, which may affect some surgical procedures, such as the transcondylar surgical approach. Methods: In the study, 25 adult human skulls belonging to Bursa Uludağ University Anatomy Laboratories were evaluated. The 22 parameters were measured on the skulls. Results: The distance between the hypoglossal canal and the anterior border of the occipital condyle was found to be 15.8±2.8 mm on the left side and 15.8±3.1 mm on the right side. The external distance between the hypoglossal canal and the anterior border of the occipital condyle was found to be 11.5±2 mm on the left and 11.6±2 mm on the right. The distance between the hypoglossal canal and the posterior margin of the occipital condyle was 11.7±1.8 mm on the left side and 12.2±2.1 mm on the right side. Furthermore, the distance measured externally between the same anatomical structures was found to be 14.04±1.89 mm and 14.4±1.6 mm on the left and right, respectively. We also found a positive correlation between the length of the foramen magnum and the occipital condyle. In addition, the diameter of the foramen magnum and the distance between the hypoglossal canal and the anterior margin of the occipital condyle were positively correlated. Conclusion: In the transcondylar approach, the locations of important anatomical structures must be well known to perform a safe occipital condyle resection without harming the neural tissue. Especially surgeons should pay attention to the distances between the hypoglossal canal and the anterior and posterior margins of the occipital condyle in order to prevent hypoglossal nerve injury. The operational success of a condylectomy may be affected by the length of the hypoglossal canal. A detailed anatomical assessment is needed before similar procedures to avoid surgical injuries. How to cite this article: Yıldız Yılmaz M, Babacan S, Kafa İM, Coşkun İ. Morphological analysis of the hypoglossal canal and its relationship with surrounding anatomical structures. J Med Dent Invest 2023; 4: e230343. https://doi.org/10.5577/jomdi.e230343

Anterior segment optical coherence tomography in pediatric ocular pathology: imaging study of 115 eyes

ABSTRACT Objective To assess the pediatric anterior segment characteristics in ocular pathology using spectral domain optical coherence tomography (SD-OCT). Methods This case series follows 115 eyes of 78 children (2–17 years) with anterior segment pathology in an academic facility. The anterior segment OCT (AS-OCT) analysis was done using the Optopol Revo 80 high-resolution SD-OCT using an imaging adapter. All pathological features visible on imaging were observed, studied, tabulated, and analyzed. Results The average age was 11.84 years, with 44 males and 34 females. The primary clinical diagnosis was cataract in 40 (34.8%) eyes, followed by corneal disease in 28 (24.3%) eyes, glaucoma in 18 (15.7%) eyes, and trauma in 15 (13%) eyes. Systemic diseases were associated with 20.9% of the cases. The commonest imaging pathology observed was lens opacification in 43 (37.4%), increased reflectivity of the cornea in 31 (28.2%), corneal stromal thinning in 34 (29.6%), increased corneal thickness in 28 (24.3%), a shallow anterior chamber in 17 (14.8%), and cells in the anterior chamber in 18 (15.7%) eyes, along with a multitude of other findings. Conclusion This study demonstrates that anterior segment OCT is a useful non-contact technique for the detailed anatomic and pathologic assessment of pediatric ocular diseases.

Imaging and guiding intervention for tricuspid valve disorders using 3-dimensional transesophageal echocardiography in pediatric and congenital heart disease.

In the pediatric and congenital heart disease (CHD) population, tricuspid valve (TV) disorders are complex due to the variable TV morphology, its sophisticated interaction with the right ventricle as well as associated congenital and acquired lesions. While surgery is the standard of care for TV dysfunction in this patient population, transcatheter treatment for bioprosthetic TV dysfunction has been performed successfully. Detailed and accurate anatomic assessment of the abnormal TV is essential in the preoperative/preprocedural planning. Three-dimensional transthoracic and 3D transesophageal echocardiography (3DTEE) provides added value to 2-dimensional imaging in the characterization of the TV to guide therapy and 3DTEE serves as an excellent tool for intraoperative assessment and procedural guidance of transcatheter treatment. Notwithstanding advances in imaging and therapy, the timing and indication for intervention for TV disorders in this population are not well defined. In this manuscript, we aim to review the available literature, provide our institutional experience with 3DTEE, and briefly discuss the perceived challenges and future directions in the assessment, surgical planning, and procedural guidance of (1) congenital TV malformations, (2) acquired TV dysfunction from transvenous pacing leads, or following cardiac surgeries, and (3) bioprosthetic TV dysfunction.

Global Iliac Branch Study: Image-based Detailed Anatomic Assessment and Device Performance

Iliac branch devices are designed to preserve patency of the internal iliac artery for endovascular repair of aortoiliac aneurysms. The Global Iliac Branch Study (NCT05607277) is an international, multicenter, retrospective study of over 300 iliac branch devices with diverse use. The objective of this project was to evaluate potential anatomic determinants of adverse iliac events. Patients were included if they had both pre- and post-treatment computed tomography imaging available after implantation of a bifurcated device. Morphologic measurements included arterial diameters, stenosis, calcification, aortic and iliac bifurcation angles, and tortuosity indices (Fig), performed by a core laboratory with a standardized and validated protocol. Adverse iliac events were defined as type I or III endoleak, occlusion, device constriction (due to either narrow anatomy or another component), or clinical events requiring reintervention of the ipsilateral iliac branch system. This abstract is based on univariate analysis. Paired t test was used to compare tortuosity indices and splay angles pre- and post-treatment. Logistic regression was used to assess associations between anatomic measurements and adverse iliac events. Analysis was performed by iliac system (ie, bilaterally treated patients’ right and left sides were analyzed independently). We analyzed 297 subjects (286 males, 11 females) with 331 iliac branch devices (104 nitinol, 227 stainless steel). Mean clinical follow-up was 3.8 years. Mean baseline total iliac artery index was 1.47 (range, 1.44 to 1.50), mean baseline common iliac artery index was 1.10 (range, 1.09 to 1.12). Changes in iliac artery tortuosity indices and aortic and iliac splay angles are reported in Table. Anatomy is significantly straightened with treatment in all devices. There were 54 adverse iliac events in 44 systems, requiring 35 reinterventions (median time to reintervention, 41 days; range, 0 days to 6.2 years). There were 18 endoleaks (17 type I, 1 type III), 29 occlusions, and five device constrictions. In nitinol devices, diameter of the internal iliac landing zone <10 mm and non-conformability (reduction in total iliac index beyond 15%) were associated with adverse iliac events (odds ratio [OR], 14; P = .016 and OR, 7.8; P = .021, respectively.) In the stainless steel devices, no significant univariate associations were found with anatomic measurements. These results suggest that purpose-built iliac branch devices are highly efficacious in treating tortuous iliac anatomy, with a high patency rate and low reintervention rate. Some anatomic factors are strongly predictive of adverse iliac events in nitinol devices.TableChanges in iliac artery tortuosity indices and splay anglesPre-treatment [95% CI]Post-treatment [95% CI]P-valueAll iliac branch systems (n = 331) Total iliac artery index1.47 [1.44-1.50]1.31 [1.28-1.33]<.0001 Common iliac artery index1.10 [1.09-1.12]1.04 [1.03-1.04]<.0001 Aortic splay angle58.3 [56.2-60.5]41.4 [39.6-43.1]<.0001 Iliac branch splay angle52.3 [49.7-54.8]47.4 [45.3-49.6]<.0001Nitinol iliac branch systems (n = 104) Total iliac artery index1.53 [1.47-1.60]1.44 [1.38-1.50]<.0001 Common iliac artery index1.13 [1.10-1.16]1.06 [1.05-1.08]<.0001 Aortic splay angle56.4 [52.1-60.8]45.3 [42.3-48.3]<.0001 Iliac branch splay angle48.0 [43.5-52.5]44.5 [40.7-48.3].0633Stainless steel iliac branch systems (n = 227) Total iliac artery index1.44 [1.42-1.47]1.25 [1.23-1.26]<.0001 Common iliac artery index1.09 [1.07-1.10]1.03 [1.02-1.03]<.0001 Aortic splay angle59.2 [56.8-61.7]39.6 [37.5-41.7]<.0001 Iliac branch splay angle54.2 [51.1-57.3]48.8 [46.2-51.4]<.0001CI, Confidence interval. Open table in a new tab

ISUOG Practice Guidelines (updated): performance of fetal magnetic resonance imaging.

ISUOG Practice Guidelines (updated): performance of fetal magnetic resonance imaging.

Diagnostic radiology methods for assessing coronary artery bypass graft viability

The review describes available modern radiological methods which are currently applied for a detailed and comprehensive anatomical and functional assessment of the viability of various coronary artery bypass grafts. In addition, it presents some aspects of the implementation of these methods and clinical interpretation of the results.

Additional value of advanced ultrasonography in pregnancies with two inconclusive cell-free DNA draws.

We aimed to evaluate the additional value of advanced fetal anatomical assessment by ultrasound in pregnancies with twice inconclusive noninvasive testing (NIPT) due to low fetal fraction (FF). We performed a multicenter-retrospective study between 2017 and 2020 including 311 pregnancies with twice inconclusive NIPT due to low FF≤1%. Women were offered invasive testing and advanced fetal anatomical assessment at ≤18weeks' gestation. Ultrasound findings, genetic testing, and pregnancy/postnatal outcomes were evaluated. Ninety-two/311 (29.6%) women underwent invasive testing. Structural anomalies were diagnosed in 13/311 (4.2%) pregnancies (nine at the first scan and four at follow-up). In 6/13 (46.2%) cases, genetic aberrations were confirmed (one case of Trisomy 13 (detectable by NIPT), two of Triploidy, one of 16q12-deletion, HCN4-mutation and UPD(16) (nondetectable by NIPT). Genetic aberrations were found in 4/298 (1.3%) structurallynormal pregnancies (one 47XYY, two microscopic aberrations, one monogenic disorder found postpartum). Structural anomalies in genetically normal fetuses (2.0%) were not more prevalent compared to the general pregnant population (OR 1.0 [0.4-2.2]). In pregnancies with twice inconclusive NIPT due to low FF, fetal structural anomalies are not more prevalent than in the general obstetric population. The detailed anatomical assessment has the added value to detect phenotypical features suggestive of chromosomal/genetic aberrations and identify pregnancies where advanced genetic testing may be indicated.

Role of Echocardiography in the Transcatheter Closure of Atrial Septal Defect

Transcatheter closure of secundum atrial septal defect (ASD) is one of the most common structural cardiac interventions. Imaging the defect is the cornerstone of the procedure at different stages of the intervention. The imaging modalities most commonly used are transthoracic and transesophageal echocardiography (TTE and TEE, respectively). Less commonly used are intracardiac echocardiogram and fusion navigation techniques. From the planning stage, a detailed anatomic and hemodynamic assessment of ASD is required for deciding suitability of device closure. Intraprocedural imaging guidance again is essential for a successful device deployment. Various assisted techniques like balloon assistance also require live TEE guidance. Confirming an acceptable device deployment is imaging dependent. Long-term follow-up of the patient for different parameters is done with the help of echocardiographic screening. A detailed understanding of echocardiographic imaging at different stages of the ASD device closure is the key for success.

Recommendations in pre-procedural imaging assessment for transcatheter aortic valve implantation intervention: Italian Society of Cardiology (SIC)-Italian Society of Medical and Interventional Radiology (SIRM) position paper part 1 (Clinical Indication and Basic Technical Aspects, Heart Team, Role of Echocardiography).

Non-invasive cardiovascular imaging owns a pivotal role in the preoperative assessment of patients for transcatheter aortic valve implantation (TAVI), providing a wide range of crucial information to select the patients who will benefit the most and have the procedure done safely. Although advanced cardiac imaging with cardiac computed tomography is routinely used for a detailed anatomic assessment before TAVI, echocardiography remains the first imaging modality to assess aortic stenosis severity and to provide essential functional information. This document results from the collaboration between the Italian Society of Cardiology (SIC) and the Italian Society of Medical and Interventional Radiology (SIRM), aiming to produce an updated consensus statement about the pre-procedural imaging assessment in patient for TAVI. The writing committee is composed of radiologists and cardiologists, experts in the field of cardiac imaging and structural heart diseases. Part 1 of the document, after a brief overview of the clinical indication and basic technical aspects of TAVI, will focus on the role of echocardiography in TAVI pre-procedural planning.

Prenatal Diagnosis of Right Sided Inguinoscrotal Hernia Associated with Severe Growth Restriction in a Fetus with Trisomy 18: A Case Report

AbstractFetal inguinoscrotal hernia is an uncommon occurence in the prenatal life, and published literature on it is scarce. This is a type of indirect hernia that results from abnormal migration of the small bowel into the scrotum via the patent processus vaginalis. We present a case of prenatal diagnosis of right sided fetal inguinoscrotal hernia, with contralateral hydrocele and severe fetal growth restriction confirmed as Trisomy 18 in subsequently performed chromosomal analysis. The index case presented at 35+2 weeks of gestation with a right sided solid scrotal mass with a regular contour, mixed echogenic texture with a few echo-free areas, a distinctive arterial supply and characteristic peristaltic movements. Fetal demise was noted one week later. The diagnosis was confirmed by postnatal examination. Prenatal diagnosis of fetal inguinoscrotal hernia should be followed up with detailed anatomical assessment and chromosomal analysis if indicated by the presence of additional abnormalities. Isolated cases require surgical repair in the neonatal period to avoid sequelae and complications.

AIUM Practice Parameter for the Performance of Detailed Diagnostic Obstetric Ultrasound Examinations Between 12 Weeks 0 Days and 13 Weeks 6 Days.

AIUM Practice Parameter for the Performance of Detailed Diagnostic Obstetric Ultrasound Examinations Between 12 Weeks 0 Days and 13 Weeks 6 Days.

Facial Nerve Arterial Arcade Supply in Dural Arteriovenous Fistulas: Anatomy and Treatment Strategies.

Endovascular treatment of petrous dural AVFs may carry a risk of iatrogenic facial nerve palsy if the facial nerve arterial arcade, an anastomotic arterial arch that supplies the geniculate ganglion, is not respected or recognized. Our purpose was to demonstrate that the use of a treatment strategy algorithm incorporating detailed angiographic anatomic assessment allows identification of the facial nerve arterial arcade and therefore safe endovascular treatment. This was a retrospective cohort study of consecutive petrous dural AVF cases managed at Toronto Western Hospital between 2006 and 2018. Our standard of care consists of detailed angiographic assessment followed by multidisciplinary discussion on management. Arterial supply, primary and secondary treatments undertaken, angiographic outcomes, and clinical outcomes were assessed by 2 independent fellowship-trained interventional neuroradiologists. Fifteen patients had 15 fistulas localized over the petrous temporal bone. Fistulas in all 15 patients had direct cortical venous drainage and received at least partial supply from the facial nerve arterial arcade. Following multidisciplinary evaluation, treatment was performed by endovascular embolization in 8 patients (53%) and microsurgical disconnection in 7 patients (47%). All patients had long-term angiographic cure, and none developed iatrogenic facial nerve palsy. By means of our treatment strategy based on detailed angiographic assessment and multidisciplinary discussion, approximately half of our patients with petrous AVFs were cured by endovascular treatment, half were cured by an operation, and all had preserved facial nerve function.

P1712 How the speed and high-level data acquisition of 3D Echocardiography benefitted surgical planning in a complex aortic root abscess case

Abstract Introduction Despite 3D echocardiography (3DE) obtaining significantly greater data than 2D echocardiography (2DE), its underutilised in assessing cardiac anatomy and dynamics. It eliminates the need for geometric modelling and assumptions about cardiac shape and permits high levels of post processing, with a single 3DE volumetric image allowing (a) generation of unlimited multiplanar reconstruction (MPR) 2D images, (b) reconstruction of volume-rendered 3D images and (c) real-time live 3D imaging. We describe the case of a highly anxious patient with life-threatening complex aortic valve endocarditis and aortic root abscess, refusing transesophageal echocardiography (TOE) under general anaesthesia, but diagnosed using rapid 3DE-TOE under sedation. Case A 25-year-old-female intravenous drug user presented to our institution with collapse after a 1-month history of constitutional symptoms. Her background included bicuspid aortic valve disease with severe aortic stenosis. On admission, leucophilia (WCC 18x109/L), anaemia (Hb 70g/L) and Staphylococcus Aureus bacteraemia were present. Bedside transthoracic echocardiography (TTE) revaled a likely aortic root abscess. Cardiac surgeons recommended urgent surgery. The patient was highly anxious however and refused pre-operative TOE under general anaesthesia. She reluctantly agreed to a ‘fast’ TOE under sedation. She tolerated a study of only 7 minutes with only single 3D image acquisitions of the mitral and aortic valves and aortic root being necessary for post-processed generation of highly detailed anatomical assessment of endocarditis, permitting surgical planning (Figs 1-4). These demonstrated severe infection of both aortic valve leaflets, perforation of the major leaflet, severe mixed aortic valve disease and infection throughout the aortic root with multiple abscess cavities. She subsequently underwent urgent bioprosthetic aortic valve replacement and root reconstruction and made an excellent recovery. Discussion Valve endocarditis with leaflet destruction and aortic root abscesses are potentially fatal, requiring urgent surgery. The preferred standard for diagnosing aortic root abscesses is TOE over TTE. This is because of the greater anatomical resolution of intracardiac structures, crucial in pre-operative surgical planning. Due to the need for a diagnostic TOE study here in this complex case rapidly, the ability to obtain such a vast amount of post processed data using two rapidly acquired TOE 3D images under sedation rather than anaesthesia was crucial in guiding the cardiac surgeon and benefitting her clinical outcome. Conclusion We encourage clinicians to use 3DE routinely in patients needing detailed and accurate anatomical and functional assessment, and in those that are complex or technically difficult given its ability to rapidly produce unrivalled echocardiographic data through unlimited post-processed MPR images including volume-rendered and colour-doppler. Abstract P1712 Figure. 4 MPR 2D images from single 3DE image

Cardiac CT and Structural Heart Disease Interventions (Non-TAVI)

The use of cardiac CT is well established in the TAVR sphere and gaining traction as an integral part of pre-procedural planning for left 13 atrial appendage closure (LAAC) and transcatheter mitral valve replacement (TMVR. We aim to review the recent evidence regarding the accuracy of cardiac CT for left atrial sizing and device selection and discuss the contribution of cardiac CT to decreasing complication rates in real-world experience as compared with clinical trials. Pre-procedural CT imaging has evolved to become an integral part of LAA closure and TMVR. For LAA closure, CT imaging provides detailed anatomic assessment of the LAA and surrounding structures and accurate measurements for device sizing. These can facilitate device and equipment selection and enhance safety and outcomes with intraprocedural guidance with transesophageal echocardiography or intracardiac echocardiography. For TMVR, pre-procedural CT is necessary to assess the potential risk of LVOT obstruction and determine device sizing. Such assessments can help pre-plan the potential need for adjunctive strategies to lower the risk of LVOT obstruction. CT imaging has gained important roles in the field of structural interventions, and understanding how to utilize this tool is an important skill to acquire as a contemporary comprehensive interventionist. Pre-procedural CT imaging has evolved to become an integral part of LAA closure and TMVR.

Echocardiography guidance of atrial septal defect closure.

Transcatheter procedures offer less invasive approaches allowing rapid recovery and earlier hospital discharge. A number of international guidelines have defined the role of echocardiography spanning diagnosis, detailed anatomical assessment, device sizing and selection, peri-procedure guidance and post device surveillance. This review discusses the role of echocardiography in transcatheter atrial septal defect (ASD) closure. It describes a systematic approach to assessment including the crucial role of three dimensional echo and provides the reader with key information required during device sizing and procedure guidance.

Computational anatomy of the dens axis evaluated by quantitative computed tomography: Implications for anterior screw fixation.

The surgical fracture fixation of the odontoid process (dens) of the second cervical vertebra (C2/axis) is a challenging procedure, particularly in elderly patients affected by bone loss, and includes screw positioning close to vital structures. The aim of this study was to provide an extended anatomical knowledge of C2, the bone mass distribution and bone loss, and to understand the implications for anterior screw fixation. One hundred and twenty standard clinical quantitative computed tomography (QCT) scans of the intact cervical spine from 60 female and 60 male European patients, aged 18-90 years, were used to compute a three-dimensional statistical model and an averaged bone mass model of C2. Shape and size variability was assessed via principal component analysis (PCA), bone mass distribution by thresholding and via virtual core drilling, and the screw placement via virtual positioning of screw templates. Principal component analysis (PCA) revealed a highly variable anatomy of the dens with size as the predominant variation according to the first principal component (PC) whereas shape changes were primarily described by the remaining PCs. The bone mass distribution demonstrated a characteristic 3D pattern, and remained unchanged in the presence of bone loss. Virtual screw positioning of two 3.5 mm dens screws with a 1 mm safety zone was possible in 81.7% in a standard, parallel position and in additional 15.8% in a twisted position. The approach permitted a more detailed anatomical assessment of the dens axis. Combined with a preoperative QCT it may further improve the diagnostic procedure of odontoid fractures. © 2017 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 35:2154-2163, 2017.