3D Multiplanar Reconstruction Research Articles

Ocular biometry in rabbits using computed tomography.

To describe a repeatable method of measuring ocular structures and to establish ocular biometry reference ranges in adult domestic rabbits (Oryctolagus cuniculus) without medical history or imaging findings consistent with ophthalmic disease using a 64-slice multidetector computed tomography scanner. In this retrospective and observational anatomic study, 100 eyes from 50 rabbits without medical history or imaging findings consistent with ophthalmic disease who received a head computed tomography scan were selected for measurement of globe length, width, and height using 3D multiplanar reconstruction. Lens width and length, the anteroposterior length of the anterior and vitreous chambers, and attenuation of the lens and vitreous chamber were collected. These parameters were compared against age, sex, weight, body condition, and ear conformation. A reference guide was established, with globe width being the largest dimension (18.03 ± 0.81 mm), followed by height (17.18 ± 0.69 mm) and then length (16.64 ± 0.66 mm). Increased weight was associated with an increase in globe height (p = 2.43 × 10-5 ), length (p = 1.63 × 10-4 ), and width (p = 7.0 × 10-3 ). Increased age was associated with increased lens attenuation (p = 1.28 × 10-7 ) and increased transverse lens width (p = 1.64 × 10-3 ). Inter- and intra-observer agreement was excellent. CT is a reliable modality for measurement of ocular biometry dimensions in rabbits. These reference values can be applied to aid in identifying diseases that affect the dimensions of the ocular structures in rabbits over 18 months of age.

The effect of a smaller spacer in the PASCAL Ace on residual mitral valve orifice area.

Mitral transcatheter edge-to-edge repair (M-TEER) is an established treatment for functional mitral regurgitation (FMR) associated with a risk of creating iatrogenic stenosis. To investigate the impact of the P10 and its larger spacer compared to the narrower Ace and its smaller spacer on reduction of mitral valve orifice area (MVOA) during M-TEER. Consecutive patients undergoing M-TEER for treatment of severe FMR were screened retrospectively. Patients with a single PASCAL device implantation within the central segments of the MV leaflets, non-complex anatomy, and baseline MVOA ≥ 3.5cm2 were selected. Intraprocedural transesophageal echocardiography was used to compare MVOA reduction with 3D multiplanar reconstruction and direct planimetry. Device selection did not follow a prespecified MVOA threshold. Seventy-two patients (81.0 years, IQR {74.3-85.0}) were included. In 32 patients, the P10 was implanted (44.4%). MR severity (p = 0.66), MR reduction (p = 0.73), and body surface area (p = 0.56) were comparable. Baseline MVOA tended to be smaller in P10 patients with the larger spacer (5.0 ± 1.1 vs. 5.4 ± 1.3cm2, p = 0.18), however, residual MVOA was larger in these patients (2.7 ± 0.7 vs. 2.3 ± 0.6cm2, p = 0.03). Accordingly, relative MVOA reduction was significantly less in P10 patients (- 45.9 ± 7.6 vs. - 56.3 ± 7.0%, p < 0.01). Indirect annuloplasty was more pronounced in Ace patients whereas mean transmitral gradients were similar. In FMR patients with non-complex anatomy, the larger spacer of the P10 maintains greater MVOA with similar MR reduction. Hence, the use of the PASCAL Ace device in patients with small MVOAs might correlate with a risk of both clinically relevant orifice reduction and even iatrogenic stenosis.

Application research of AI-assisted compressed sensing technology in MRI scanning of the knee joint: 3D-MRI perspective.

To investigate the potential applicability of AI-assisted compressed sensing (ACS) in knee MRI to enhance and optimize the scanning process. Volunteers and patients with sports-related injuries underwent prospective MRI scans with a range of acceleration techniques. The volunteers were subjected to varied ACS acceleration levels to ascertain the most effective level. Patients underwent scans at the determined optimal 3D-ACS acceleration level, and 3D compressed sensing (CS) and 2D parallel acquisition technology (PAT) scans were performed. The resultant 3D-ACS images underwent 3.5mm/2.0mm multiplanar reconstruction (MPR). Experienced radiologists evaluated and compared the quality of images obtained by 3D-ACS-MRI and 3D-CS-MRI, 3.5mm/2.0mm MPR and 2D-PAT-MRI, diagnosed diseases, and compared the results with the arthroscopic findings. The diagnostic agreement was evaluated using Cohen's kappa correlation coefficient, and both absolute and relative evaluation methods were utilized for objective assessment. The study involved 15 volunteers and 53 patients. An acceleration factor of 10.69 × was identified as optimal. The quality evaluation showed that 3D-ACS provided poorer bone structure visualization, and improved cartilage visualization and less satisfactory axial images with 3.5mm/2.0mm MPR than 2D-PAT. In terms of objective evaluation, the relative evaluation yielded satisfactory results across different groups, while the absolute evaluation revealed significant variances in most features. Nevertheless, high levels of diagnostic agreement (κ: 0.81-0.94) and accuracy (0.83-0.98) were observed across all diagnoses. ACS technology presents significant potential as a replacement for traditional CS in 3D-MRI knee scans, allowing thinner MPRs and markedly faster scans without sacrificing diagnostic accuracy. 3D-ACS-MRI of the knee can be completed in the 160s with good diagnostic consistency and image quality. 3D-MRI-MPR can replace 2D-MRI and reconstruct images with thinner slices, which helps to optimize the current MRI examination process and shorten scanning time. • AI-assisted compressed sensing technology can reduce knee MRI scan time by over 50%. • 3D AI-assisted compressed sensing MRI and related multiplanar reconstruction can replace traditional accelerated MRI and yield thinner 2D multiplanar reconstructions. • Successful application of 3D AI-assisted compressed sensing MRI can help optimize the current knee MRI process.

Virtual injection software for endovascular management of spinal dural arteriovenous fistula.

Endovascular management of spinal dural arteriovenous fistula (DAVF) is arduous because of complex angioarchitecture and motion artifacts and is limited by the two-dimensional (2D) view. However, cone beam computed tomography (CBCT) acquisitions with selective injections allow 3D multiplanar reconstructions contributing to high diagnostic, anatomical and safety value. In this study, we described the use of virtual injection software (VIS) computed from CBCT acquisition and already used for prostatic and cerebral embolization, for the endovascular management of spinal DAVFs (EmboAssist, GE HealthCare, Chicago, USA). The VIS has been designed to facilitate the analysis of the patient's vasculature during the planning of embolization procedures to define the afferent pedicles to the shunt and the incidence of oblique projection, allowing for a better anatomical understanding and helping for the selection of 2D incidence. Combined with 3D roadmapping, VIS allows vessel tracking for selective catheterism and embolization. The VIS is a useful tool for planification and navigation during endovascular treatment of spinal DAVF with a safety value.

Three-Dimensional Guided Cone-Shaped Segmentectomy Versus Lobectomy for Small-sized Non-Small Cell Lung Cancer in the Middle Third of the Lung Field.

Segmentectomy has been recommended for peripheral small-sized non-small cell lung cancer (NSCLC). This study aimed to evaluate whether three dimensionally (3D) guided cone-shaped segmentectomy can achieve long-term outcomes comparable with lobectomy for small-sized NSCLC in the middle third of the lung parenchyma. This study retrospectively screened patients with small NSCLC (≤2 cm) who underwent segmentectomy or lobectomy between January 2012 and June 2019. Tumor location was determined by 3D multiplanar reconstruction. The cone-shaped segmentectomy was performed with the guidance of 3D computed tomographic bronchography and angiography. The log-rank test, Cox hazard proportional regression, and propensity score-matching analyses were adopted for prognostic evaluation. After screening, 278 patients with segmentectomy and 174 subjects undergoing lobectomy were selected. All the patients had R0 resection, and no 30- or 90-day mortality was observed. The median follow-up time was 47.3 months. The 5-year overall survival (OS) was 99.6 %, and the disease-free survival (DFS) was 97.5 % for the patients undergoing segmentectomy. After propensity score-matching, the patients with segmentectomy (n = 112) had an OS (P = 0.530) and a DFS (P = 0.390) similar to those of the patients who underwent lobectomy (n = 112). The multivariable Cox regression analysis indicated no significant survival differences between segmentectomy and lobectomy [DFS: hazard ratio, 0.56 (95 % confidence interval (CI) 0.16-1.97, P = 0.369); OS: HR, 0.35 (95 % CI 0.06-2.06, P = 0.245)] after adjustment for other factors. Further analysis showed that segmentectomy achieved comparable OS (P = 0.540) and DFS (P = 0.930) for NSCLC in the middle-third and peripheral lung parenchyma (n = 454). For selected NSCLCs size 2 cm or smaller in the middle third of the lung field, 3D-guided cone-shaped segmentectomy was able to achieve long-term outcomes comparable with lobectomy.

A novel useful 3D multiplanar reconstruction algorithm to detect the optimal transseptal puncture positioning in percutaneous mitral valve repair

Abstract Funding Acknowledgements Type of funding sources: None. Background in transcatheter edge to edge mitral repair (TEER), the use of transesophageal echocardiography (TEE) guidance is mandatory in every procedural step. The transseptal puncture (TPS) height is measured by TEE using a four chamber view (4CV) in mid-upper esophagus between the catheter tenting in fossa ovalis and the coaptation of the mitral valve (MV) and its correct positioning influence procedural outcome. However, TSP can represents a tricky step, because of poor images, challenging interatrial septa or a malalignment of TEE probe, catheter and mitral coaptation. Aim In this abstract we describe an alternative TEE 3D technique to measure TSP height. Methods Between August 2022 and December 2022 we performed 18 cases of TEER. In all cases we obtained a measure of the height of tenting (HT) with two different techniques: the 2D view (2DV) in 4CV and the 3D reconstruction algorithm (3DA) (fig.1). This 3DA starts with a real-time single-beat 3D volume acquisition from a mid esophagus at 0 degrees view. The 3D dataset should include IAS, aortic valve, and MV. In multiplanar reconstruction (MPR), three 2D planes are reconstructed from the 3D dataset. These MPR planes must be positioned in a predefined manner with the cursors correctly aligned on the catheter tip at the level of the fossa ovalis. The first plan (P1) is an off axis 4CV oriented perpendicular to the IAS exactly on the height of the catheter tip and serves as the orientation plane. This plane allows the exact location of the tenting point and the positioning of the other two MPR planes. The crossing of the axes should be positioned in all planes at the center of the left atrium. The second plane (P2) and the third plane (P3) are oriented perpendicular to the previous one (fig.1) and each other. Rotating and moving those two planes in a stepwise manner a 4CV, including the plane passing by catheter tip and MV coaptation is obtained in P1. In order to identify the exact plane of the coaptation, while in P1 the axis passing through the MV is positioned at the center of the MV, in P2 the axis is adjusted at the point of leaflet coaptation (fig.1). The HT is then measured in P1 thus avoiding the possible foreshortening affecting a simple 2DV. Results In all cases the 3D measure was accomplished but in 3 of 18 cases the 2DV was difficult to obtain because of loss of contact between the esophagus and the probe in retroflection, in those cases the HT was measured in a 0 degrees off axis view from the tenting of the fossa to a very anterior part of the coaptation line or to anterior leaflet. In all those cases the height of tenting was underestimated (fig.2). Conclusion The 3DA described can be useful in obtaining a more precise and reliable measure of the HT even in anatomical challenging patients. A comparative study that consents to investigate the correlation between the two methods and the inter and intra observer agreement is mandatory and planned at our institution.

Tricuspid leaflet identification on 2D multiplane transoesophageal echocardiography: lessons from 3D

Abstract Funding Acknowledgements Type of funding sources: None. Background —Tricuspid valve (TV) leaflet identification by two-dimensional (2D) transoesophageal echocardiography (TOE) is complex due to the high variability of the combinations of leaflets visualized in each view. While three-dimensional (3D) imaging can easily overcome this problem by acquiring the whole valve anatomy, the overall image quality is often suboptimal and the technique somewhat unsuitable for real-time monitoring during interventional procedures like TriClip implantation. Using information derived from both 2D and multiplanar reconstruction (MPR) of 3D datasets, we aimed at describing anatomical landmarks able to identify TV leaflets easily and effectively during multiplane 2D TOE. Methods —TOE data from 83 patients was retrospectively collected. Multiplane 2D images of the TV and matching 3D datasets recorded from the same probe position were compared to precisely identify the leaflets visualized on each 2D image. To increase the number of multiplane (orthogonal) 2D images available for analysis, a novel approach was used: the 3D data of each patient was appropriately sliced to simulate and accurately match what would be seen by "sweeping" the cursor across the TV during real-time multiplane imaging (Fig. 1). After data analysis, a comprehensive "two-step" reference table was generated. To evaluate the clinical utility of the findings, eleven (11) echocardiographers were shown a random set of 5 images, and asked to label the leaflets visualized, prior and after a brief explanation on how to use the proposed reference table. Results —After removal of redundant information, a total of 231 sets of leaflets combinations was obtained. The number of leaflets visualized (one or two) and the presence (or absence) of the interventricular septum allowed consistent identification of the TV leaflets depicted in the 2D home view, as confirmed by correlation with the matching 3D MPR dataset. A similar analysis was carried out on the orthogonal 2D images resulting from three different multiplane cursor positions (distal, mid, and proximal to the aortic valve/interventricular septum). By combining information from the two views, leaflet identification was accurate, intuitive and easy, as summarized in the reference table (Fig. 2). The accuracy in exact leaflet recognition was rather modest (mean score of 1 out of 5) among echocardiographers with different experience in TV TOE, but significantly increased (mean score of 3.2 out of 5) with the adoption of the proposed approach, accounting for a 44% improvement in accuracy (p &amp;lt;0.001). Conclusion — Simple anatomical landmarks allow precise TV leaflet identification during multiplane 2D TOE. A simplified two-step approach significantly improves accuracy in leaflet recognition among both beginners and advanced echocardiographers.

Segmentectomy versus lobectomy for deep clinical T1a-bN0M0 non-small cell lung cancer

ObjectivesWhether segmentectomy could yield similar oncological outcomes with lobectomy for cT1a-bN0M0 non-small cell lung cancer (NSCLC) in the deep lung parenchyma remained unclear. This study aimed to compare the long-term prognosis of segmentectomy and lobectomy for deep NSCLC. Materials and methodsWe retrospectively screened cT1a-bN0M0 NSCLC patients who underwent segmentectomy or lobectomy between 2012 and 2019. The 3D multiplanar reconstruction software was used to determine the tumor location. Log-rank test, Cox hazard proportional regression, and propensity score matching analyses were adopted for prognostic evaluation. ResultsIn total, 321 patients with segmentectomy and 239 subjects undergoing lobectomy with a median follow-up time of 48.2 months remained. All the patients had a R0 resection, and no 30-day or 90-day mortality was observed. The 5-year overall survival and disease-free survival were 99.0% and 96.6% for patients undergoing segmentectomy. No significant survival differences existed between segmentectomy and lobectomy after adjusting other factors (disease-free survival, DFS: HR = 1.20, 95%CI: 0.49–2.99, P = 0.688; overall survival, OS: HR = 1.09, 95%CI: 0.30–3.95, P = 0.892). After propensity score matching, patients with segmentectomy (n = 128) had a similar OS (P = 0.870) and DFS (P = 0.900) with those receiving lobectomy (n = 128). To further evaluate the outcomes of segmentectomy for deep lung cancer, 557 peripheral lung cancer patients who underwent segmentectomy at the same period were taken as the reference. As expected, segmentectomy for deep lesions achieved equivalent OS (P = 0.610) and DFS (P = 0.580) with the peripheral lesions. ConclusionsSegmentectomy could achieve comparable long-term outcomes with lobectomy for deep cT1a-bN0M0 NSCLC with careful preoperative design and 3D navigation.

Creation of 3D Stereo and MPR Color Anatomical Charts in the Hepatic Segments

We used the Voronoi diagram of a computed tomography (CT) application (i.e., CT liver volume measurement) to depict the liver area, and we obtained depictions of the hepatic segments as a three-dimensional (3D) image based on clinical data; this information can be used for the patient's education and for surgical planning. The hepatic segments use the inter-relationships among the eight subsegments illustrated by Couinaud, those indicated by the portal veins and those provided by hepatic veins. The liver has dual portal and arterial innervation, with the thick portal vein intertwined with thin arteries similar to the intertwining of ivy plants. Couinaud divided the liver into eight segments (S1 to S8) based on portal vein casts. The Voronoi diagram estimates the dominant region of the portal vein, divides the liver into segments, and produces 3D images and multiplanar reconstruction (MPR) images in color. To support understanding of Couinaud's eight hepatic segments (which are explained only in the illustration of the frontal view of the liver), using 3D images created by the Voronoi diagram, we created 3D stereo color anatomical charts of the liver that Couinaud's eight hepatic segments can be confirmed from multiple directions. In addition, we created the MPR color anatomical charts of the liver (S1 to S8) that can be confirmed by color from three directions: axial images, coronal images, and sagittal images in the same way. We converted the data of this anatomical chart into an electronic file that provides a tool that can be easily used in radiological examinations, and we were able to make improvements based on requests from users.

Jugular foramen anatomy in lateral skull base paraganglioma surgery

To detalize the anatomy of the jugular foramen according to the comparison of cadaver dissections findings and the CT scans data that were performed before the dissections, for improvement of quality of treatment of patients with temporal bone paraganglioma (Fisch type C). The data of CT scans and the steps of the approaches to the jugular foramen (retrofacial and infratemporal approaches with opening of jugular bulb and identification of the anatomical structures of jugular foramen) were analyzed on 10 cadaver heads, 20 sides. Clinical implementation was demonstrated in case of temporal bone paraganglioma type C. Based on the detail study of the CTs data we revealed the individual features of the temporal bone structures. Due to the results of 3D rendering the average length of the jugular foramen in anterior-posterior direction was 10.1 mm. The length of vascular part was larger than the nervous part. The posterior part had the bigger height wherein the shortest part we detected between jugular ridges, which in some cases caused the dumbbell shape of jugular foramen. According to 3D multiplanar reconstruction the distances between jugular crests (3.0 mm) had the lowest measures and the largest was between internal auditory canal (IAC) and jugular bulb (JB) (8.01mm). At the same time, one of the largest variations of values was also identified between IAC and JB (from 4.39 to 9.84 mm). The distance between the facial nerve in the mastoid segment and JB was variable (from 3.4 to 10.2 mm) and determined by the volume and position of the JB. The results of the dissection corresponded to the measurements according to the CT scans, taking into account the 2-3 mm error due to the massive removal of temporal bone during performing of surgical approaches. The detailed knowledge of the surgical anatomy of the jugular foramen based on a thorough analysis of preoperative CT data is the key to an adequate surgical tactic for the removal of different types of temporal bone paraganglioma while preserving the function of vital structures and the quality of life. A larger study on the big data is needed to determine the statistical relationship between the volume of JB and the size of the jugular crest; the correlation between the dimensions of jugular crests and the tumor invasion in the anterior part of the jugular foramen.

Arthroscopic defect size measurement in osteochondral lesions of the talus underestimates the exact defect size and size measurement with arthro-MRI (MR-A) and high-resolution flat-panel CT-arthro imaging (FPCT-A).

The size of osteochondral lesions of the talus (OLTs) is highly relevant for their treatment. In addition to intraoperative measurement of defect size, preoperative planning by means of magnetic resonance imaging (MRI) or computed tomography (CT) is crucial. Four defects of different sizes and depths were created on the talar joint surface in 14 cadaver feet. All defects were evaluated, both arthroscopically and via arthrotomy with a probe. Arthro-MRI (MR-A) and high-resolution flat-panel CT arthro scans (FPCT-A) were acquired. Length, width, and depth were measured for every defect and the defect volume was calculated. To determine the exact defect size, each talar defect was filled with plastic pellets to form a cast and the casts were scanned using FPCT to create a 3D multiplanar reconstruction data set. Finally, the surgically measured values were compared with the radiological values and the exact defect size. Overall, the surgically measured values (both arthroscopic and open) underestimated the exact defect size (p < 0.05). Arthroscopically determined defect length and width showed the largest deviation (p < 0.05) and underestimated the size in comparison with MR-A and FPCT-A. The FPCT-A measurements demonstrated higher correlation with both the arthroscopic and open surgical measurements than did the MR-A measurements (p < 0.05). The exact defect size is underestimated on intraoperative measurement, in both arthroscopic and open approaches. Arthroscopic defect size measurement underestimates defect size in comparison with MR-A and FPCT-A. FPCT-A was shown to be a reliable imaging technique that allows free image reconstruction in every plane and could be considered as the new reference standard for preoperative evaluation of defect size in OLT.

The Complete and Two-Turn Cochlear Duct Length Among Filipinos

&#x0D; &#x0D; &#x0D; &#x0D; ABSTRACTObjective: This study aims to measure the complete and two-turn cochlear duct lengths in a Filipino population using archived CT scan images.&#x0D; &#x0D; &#x0D; &#x0D; &#x0D; Methods: &#x0D; Design: Retrospective Review of Records&#x0D; Setting:Tertiary Government Training Hospital&#x0D; Participants: CT Scan Images of 255 patients&#x0D; &#x0D; &#x0D; &#x0D; &#x0D; Cochlear images of patients who underwent cranial, facial, orbital, paranasal sinus and temporal bone CT scans from January 2019 to December 2019 were analyzed. Coronal oblique images from 3D multiplanar reconstructions were obtained and a single linear measurement (‘A’ value) was used as the spiral coefficient to calculate the complete cochlear duct length (CDL) and two- turn length (2TL).&#x0D; &#x0D; &#x0D; &#x0D; &#x0D; Results: A total of 510 cochlear images were obtained from the CT scan images of 255 subjects (143 males, 112 females aged 1 to 81 years; mean age = 47 years). The mean ‘A’ value was 8.81 mm (SD = 0.20). The mean complete cochlear duct length was 32.68 mm (31.01 mm – 35.50 mm; SD = 0.834) while the mean two-turn cochlear duct length was 29.61 mm (28.14 mm – 32.08 mm; SD = 0.732). The complete and two-turn cochlear duct lengths in males were found to be significantly longer than in females (p = .001). No significant difference was found between cochlear measurements for left and right ears.&#x0D; &#x0D; &#x0D; &#x0D; &#x0D; Conclusion: The mean complete cochlear duct length among Filipinos in our study measures 32.68 mm while the mean two-turn cochlear duct length measures 29.61mm. Both complete and two-turn cochlear duct lengths were longer among Filipino males than among females.&#x0D; &#x0D; &#x0D; &#x0D; &#x0D; &#x0D; &#x0D; &#x0D; &#x0D; &#x0D; &#x0D; &#x0D; &#x0D; &#x0D; &#x0D; &#x0D; &#x0D; &#x0D; &#x0D; &#x0D;

The surgical anatomy of a (robot-assisted) minimally invasive transcervical esophagectomy.

Transcervical esophagectomy allows for esophagectomy through transcervical access and bypasses the thoracic cavity, thereby eliminating single lung ventilation. A challenging surgical approach demands thorough understanding of the encountered anatomy. This study aims to provide a comprehensive overview of surgical anatomy encountered during the (robot-assisted) minimally invasive transcervical esophagectomy (RACE and MICE). To assess the surgical anatomy of the lower neck and mediastinum, MR images were made of a body donor after, which it was sliced at 24-μm intervals with a cryomacrotome. Images were made every 3 slices resulting in 3.200 images of which a digital 3D multiplanar reconstruction was made. For macroscopic verification, microscopic slices were made and stained every 5 mm (Mallory-Cason). Schematic drawings were made of the 3D reconstruction to demonstrate the course of essential anatomical structures in the operation field and identify anatomical landmarks. Surgical anatomy 'boxes' of three levels (superior thoracic aperture, upper mediastinum, subcarinal) were created. Four landmarks were identified: (i) the course of the thoracic duct in the mediastinum; (ii) the course of the left recurrent laryngeal nerve; (iii) the crossing of the azygos vein right and dorsal of the esophagus; and (iv) the position of the aortic arch, the pulmonary arteries, and veins. The presented 3D reconstruction of unmanipulated human anatomy and schematic 3D 'boxes' provide a comprehensive overview of the surgical anatomy during the RACE or MICE. Our findings provide a useful tool to aid surgeons in learning the complex anatomy of the mediastinum and the exploration of new surgical approaches such as the RACE or MICE.

Are severe mitral annular calcification still a contraindication to open surgery?

Abstract Background Mitral annular calcifications are considered a contraindication to open mitral valve repair/replacement, being associated with a significant risk of rupture of the atrioventricular groove or prosthesis detachment/paraprosthetic leak. Recently a scoring system has been proposed, to quantify the severity of MAC and predict the success of transcatheter valve in MAC implantation. Objective We present a series of consecutive patients with MAC undergoing sugical mitral valve replacement in recent years. Patients and methods 82 consecutive patients with MAC underwent open surgical correction from January 2019 at our centre. This was a complex cohort of patients with a high surgical risk profile (STS 5.3±3.2). The degree of MAC was moderate in 60 and severe in 22. Annular decalcification was required in 16 patients, and patch reconstruction of the AV groove in 4. The main predictor of the need for annular decalcification and reconstruction was the depth of calcium infiltration in the ventricular wall at CT. At intraoperative TEE only one patient had a significant paraprosthetic leak, that was repaired during a second short period of aortic cross-clamping. 30 days mortality was 1.2% (one patient), and 87% of patients were alive and well at one year. Comment The presence of significant mitral annular calcificaion per se should not be considered a contraindication to open mitral valve surgery. The depth of the calcifications in the ventricular wall, as measured at CT 3D multiplanar reconstructions is the best predictor of the need to decalcify/reconstruct the AV groove. Detailed imaging analysis is crucial for the success of the procedure. Funding Acknowledgement Type of funding sources: None.

3D Cinematic Volume-Rendering Technique of Traumatic Spine Injuries: A Powerful Tool for Radiology Education

Spine trauma represents a common indication for imaging in the emergency department. Multidetector CT imaging, with its advantage of multiplanar reconstructions and fast image acquisition, is the technique of choice in the initial assessment of a patient with polytrauma. While many simple spinal fractures are adequately evaluated on 2D multiplanar reconstruction images, more complex, potentially displaced fracture patterns can be more fully highlighted on 3D reconstructions. Compared with conventional volume-rendering techniques, cinematic rendering uses a complex illumination model to create a more photorealistic representation of the fracture patterns, images that are certain to excite both trainees and clinicians. This review demonstrates the educational value and clinical utility of 3D cinematic rendering images in understanding complex spinal column injuries.Learning Objective: To demonstrate the methodology, clinical applicability, and educational utility behind 3D photorealistic cinematic rendering images of spine injuries, with emphasis on the “tension bands” biomechanical concept

Advances in Procedural Echocardiographic Imaging in Transcatheter Edge-to-Edge Repair for Mitral Regurgitation.

Transcatheter edge-to-edge repair (TEER) therapy is recommended by the American College of Cardiology/American Heart Association (ACC/AHA) guidelines for selected patients with symptomatic severe or moderate-severe mitral regurgitation (MR). Echocardiography, in particular transesophageal echocardiography (TEE), plays a critical role in procedural planning and guidance for TEER. Recent innovations and advances in TEE techniques including three-dimensional (3D) imaging, unlimited x-plane imaging, live 3D multiplanar reconstruction, as well as transillumination imaging with color Doppler and transparency rendering have further enhanced procedural imaging for TEER, especially for complex diseases including commissural defects, clefts, and multi-segment pathologies. This review discusses the technology of these advanced procedural imaging techniques and provides a “step-by-step” guide on how to apply them during the TEER procedure with a focus on their added values in treatment of complex valve lesions.

Geometric changes in aortic root replacement using Freestyle prosthesis

BackgroundThe Medtronic Freestyle prosthesis has proven to be a promising recourse for aortic root replacement in various indications. The present study aims to evaluate clinical outcomes and geometric changes of the aorta after Freestyle implantation.MethodsBetween October 2005 and November 2020, the computed tomography angiography (CTA) data of 32 patients were analyzed in a cohort of 68 patients that underwent aortic root replacement using Freestyle prosthesis. The minimum and maximum diameters and areas of the aortic annulus, aortic root, ascending aorta, and the proximal aortic arch were measured at a plane perpendicular to the long axis of the aorta using 3D multiplanar reconstruction in both the preoperative (n = 32) and postoperative (n = 10) CTAs. Moreover, volumetric changes of the aortic root and ascending aorta were quantified.ResultsMean age was 64.6 ± 10.6 years. Indications for surgery using Freestyle prosthesis were combined aortic valve pathologies, aortic aneurysm or dissection, and endocarditis, with concomitant surgery occurring in 28 out of 32 patients. In-hospital mortality was 18.6%.Preoperative diameter and area measurements of the aortic annulus strongly correlated with the implanted valve size (p < 0.001). Bicuspid valve was present in 28.1% of the patients. Diameter and areas of the aortic root decreased after freestyle implantation, resulting in a reduction of the aortic root volume (45.6 ± 26.3 cm3 to 18.7 ± 4.5 cm3, p = 0.029). Volume of the aortic root and the ascending aorta decreased from 137.3 ± 65.2 cm3 to 54.5 ± 21.1 cm3 after Freestyle implantation (p = 0.023).ConclusionImplantation of the Freestyle prosthesis presents excellent results in restoring the aortic geometry. Preoperative CTA measurements are beneficial to the surgical procedure and valve selection and therefore, if available, should be considered in pre-operative planning.

Simulation of superselective catheterization for cerebrovascular lesions using a virtual injection software

BackgroundThis report addresses the feasibility of virtual injection software based on contrast-enhanced cone-beam CTs (CBCTs) in the context of cerebrovascular lesion embolization. Intracranial arteriovenous malformation (AVM), dural arteriovenous fistula (AVF) and mycotic aneurysm embolization cases with CBCTs performed between 2013 and 2020 were retrospectively reviewed. Cerebrovascular lesions were reviewed by 2 neurointerventionalists using a dedicated virtual injection software (EmboASSIST, GE Healthcare; Chicago, IL). Points of Interest (POIs) surrounding the vascular lesions were first identified. The software then automatically displayed POI-associated vascular traces from vessel roots to selected POIs. Vascular segments and reason for POI identification were recorded. Using 2D multiplanar reconstructions from CBCTs, the accuracy of vascular traces was assessed. Clinical utility metrics were recorded on a 3-point Likert scale from 1 (no benefit) to 3 (very beneficial).ResultsNine cases (7 AVM, 1 AVF, 1 mycotic aneurysm) were reviewed, with 26 POIs selected. Three POIs were in 2nd order segments, 8 POIs in 3rd order segments and 15 POIs in 4th order segments of their respective arteries. The reviewers rated all 26 POI traces – involving a total of 90 vascular segments – as accurate. The average utility score across the 8 questions were 2.7 and 2.8 respectively from each reviewer, acknowledging the software’s potential benefit in cerebrovascular embolization procedural planning.ConclusionThe operators considered CBCT-based virtual injection software clinically useful and accurate in guiding and planning cerebrovascular lesion embolization in this retrospective review. Future prospective studies in larger cohorts are warranted for validation of this modality.

3D morphometric analysis of ascending aorta as an adjunctive tool to predict type A acute aortic dissection.

BackgroundAcute type A aortic dissection (AAAD) is a pathological process that implicates the ascending aorta and represents a surgical emergency burdened by high mortality if not promptly treated in the first hours of onset. Despite best efforts, the annual incidence rates of aortic dissection has remained stable over the past decades. We measured aortic dimensions (aortic diameters, area, length and volume) using 3D multiplanar reconstruction imaging with the purpose of refining the risk- morphology for AAAD.MethodsComputerized tomography angiography studies of three groups were compared retrospectively: patients affected by AAAD (AAAD group; n=71), patients affected by aortic aneurysm and subsequently subjected to ascending aorta replacement (Aneurysm, n=77) and a healthy aorta’s group (Control, n=75).ResultsMean diameters of AAAD (4.9 cm) and Aneurysm (5.1 cm) aortas were significantly larger than those of the control group (3.4 cm). In AAAD patients, an ascending aorta diameter greater than 5.5 cm was observed in 18% of patients. Multiple comparisons showed statistically significant differences among mean of the ratio of aortic root area to height between the three groups (P<0.001). In frontal and sagittal planes, the length of the ascending aorta was significantly greater in patients affected by aortic pathology (AAAD and aneurysm) than in the control group (P<0.001). Significant differences were confirmed when indexing the aortic length to patient’s height and BSA, and the aortic volume to patient’s BSA.ConclusionsMaximum transverse diameter, considered separately, is not the best predictor of aortic dissection. In our opinion, the introduction into clinical practice of measurements of the area, length, and volume of the aorta, as absolute or indexed values, could improve the selection of patients who would benefit from preventive surgical aortic replacement.

Frecuencia de foramen mentoniano accesorio y variabilidad anatómica del asa anterior del nervio mentoniano en una población peruana: estudio retrospectivo de tomografía computarizada de haz cónico.

Objective: To evaluate the frequency of accessory mental foramen (AMF) and anatomical variants of the mental nerve anterior loop using cone-beam computed tomography (CBCT) in a Peruvian population. Material and methods: This retrospective cross-sectional study evaluated 80 hemi-mandibles from 40 subjects using CBCT. The sample included 38 females and 42 males, with an average age of 25±4.45 years. A 3D multi-planar reconstruction was performed to identify the location and presence of accessory mental foramina, their morphological characteristics (oval or circular), their position with respect to the mental foramen (MF), anterior loop (AL) path and other anatomical landmarks including lengths and angles. Statistical analyses included chi square and t-tests. The significance level was p&lt;0.05. Results: The frequency of AMF was 17% and the average distance AL-MF was 4.76±1.97mm. The measurements of the anterior border of AL and MF to the inferior mandibular border showed significant differences according to the sex (p&lt;0.001 and p=0.009, respectively). Conclusion: The AMF prevalence was approximately 17%. There is no association between the AMF position and its morphology, sex or side evaluated. The distances from the anterior border of the AL and from the inferior border of the MF to the inferior mandibular border were greater in males. These findings should be considered when planning implant or mini-implant placement in this region.