scholarly journals An Image-Based Workflow for Objective Vessel Wall Enhancement Quantification in Intracranial Aneurysms

Diagnostics ◽  
2021 ◽  
Vol 11 (10) ◽  
pp. 1742
Author(s):  
Sricharan S. Veeturi ◽  
Nandor K. Pinter ◽  
Andre Monteiro ◽  
Ammad A. Baig ◽  
Hamid H. Rai ◽  
...  
Keyword(s):  
High Risk ◽  
Visual Inspection ◽  
Clinical Score ◽  
Mr Images ◽  
Tof Mra ◽  
Contrast Enhanced ◽  
Potential Biomarker ◽  
The Common ◽  
Magnetic Resonance Imaging Mri ◽  
Optimal Signal

Background: VWE in contrast-enhanced magnetic resonance imaging (MRI) is a potential biomarker for the evaluation of IA. The common practice to identify IAs with VWE is mainly based on a visual inspection of MR images, which is subject to errors and inconsistencies. Here, we develop and validate a tool for the visualization, quantification and objective identification of regions with VWE. Methods: N = 41 3D T1-MRI and 3D TOF-MRA IA images from 38 patients were obtained and co-registered. A contrast-enhanced MRI was normalized by the enhancement intensity of the pituitary stalk and signal intensities were mapped onto the surface of IA models generated from segmented MRA. N = 30 IAs were used to identify the optimal signal intensity value to distinguish the enhancing and non-enhancing regions (marked by an experienced neuroradiologist). The remaining IAs (n = 11) were used to validate the threshold. We tested if the enhancement area ratio (EAR—ratio of the enhancing area to the IA surface-area) could identify high risk aneurysms as identified by the ISUIA clinical score. Results: A normalized intensity of 0.276 was the optimal threshold to delineate enhancing regions, with a validation accuracy of 81.7%. In comparing the overlap between the identified enhancement regions against those marked by the neuroradiologist, our method had a dice coefficient of 71.1%. An EAR of 23% was able to discriminate high-risk cases with an AUC of 0.7. Conclusions: We developed and validated a pipeline for the visualization and objective identification of VWE regions that could potentially help evaluation of IAs become more reliable and consistent.

scholarly journals Aneurysm risk metrics and hemodynamics are associated with greater vessel wall enhancement in intracranial aneurysms

2021 ◽  
Vol 8 (11) ◽  
Author(s):  
Sricharan S. Veeturi ◽  
Hamidreza Rajabzadeh-Oghaz ◽  
Nándor K. Pintér ◽  
Muhammad Waqas ◽  
David M. Hasan ◽  
...  
Keyword(s):  
Negative Correlation ◽  
Vessel Wall ◽  
Pearson Correlation ◽  
Resonance Imaging ◽  
Unruptured Aneurysms ◽  
Contrast Enhanced ◽  
Potential Biomarker ◽  
Weak Negative Correlation ◽  
Magnetic Resonance Imaging Mri ◽  
The Relationship

Vessel wall enhancement (VWE) in contrast-enhanced magnetic resonance imaging (MRI) is a potential biomarker for intracranial aneurysm (IA) risk stratification. In this study, we investigated the relationship between VWE features, risk metrics, morphology and hemodynamics in 41 unruptured aneurysms. We reconstructed the IA geometries from MR angiography and mapped pituitary stalk-normalized MRI intensity on the aneurysm surface using an in-house tool. For each case, we calculated the maximum intensity (CR stalk ) and IA risk (via size and the rupture resemblance score (RRS)). We performed correlation analysis to assess relationships between CR stalk and IA risk metrics (size and RRS), as well as each parameter encompassed in RRS, i.e. aneurysmal size ratio (SR), normalized wall shear stress (WSS) and oscillatory shear index. We found that CR stalk had a strong correlation (Pearson correlation coefficient, PCC = 0.630) with size and a moderate correlation (PCC = 0.472) with RRS, indicating an association between VWE and IA risk. Furthermore, CR stalk had a weak negative correlation with normalized WSS (PCC = −0.320) and a weak positive correlation with SR (PCC = 0.390). Local voxel-based analysis showed only a weak negative correlation between normalized WSS and contrast-enhanced MRI signal intensity (PCC = −0.240), suggesting that if low-normalized WSS induces enhancement-associated pathobiology, the effect is not localized.

The Utility of Non-invasive Tests for Detection of Previous Proximal-vein Thrombosis

1995 ◽  
Vol 73 (04) ◽  
pp. 592-596 ◽  
Author(s):  
Sabina Villalta ◽  
Paolo Prandoni ◽  
Alberto Cogo ◽  
Paola Bagatella ◽  
Andrea Piccioli ◽  
...  
Keyword(s):  
Clinical Evaluation ◽  
Femoral Vein ◽  
Clinical Score ◽  
Diagnostic Methods ◽  
Popliteal Vein ◽  
Venous Reflux ◽  
Study Objective ◽  
Vein Thrombosis ◽  
Non Invasive ◽  
The Common

SummaryBackground. Despite the availability of several diagnostic methods for the detection of deep-vein thrombosis (DVT), the identification of previous episodes of DVT remains a diagnostic challenge.Study objective. To assess the reliability of a combination of a standardized clinical score with three non-invasive tests: compression ultrasonography (CUS), Doppler ultrasound (DUS), and photoplethysmography (PPG), in determining the presence or the absence of previous proximal DVT.Methods. One hundred consecutive unselected outpatients were identified, who had undergone contrast venography six to nine years previously because of the clinical suspicion of DVT (confirmed in 43). They were blindly reinvestigated by a panel of trained operators unaware of venography results. They underwent a clinical evaluation of the lower limb, by applying a standardized score to five symptoms and six signs (grading each item from 0 to 3); a PPG test to determine the venous refilling time; a DUS test to determine the venous reflux separately in the common femoral and the popliteal vein; and a CUS test to determine vein compressibility in the same regions.Results. An abnormal CUS test and/or the demonstration of venous reflux in the popliteal region and/or a high clinical score (≥ 8) identified twenty-four of the 43 (56%) DVT + patients with a specificity of 89%. The combination of normal CUS with the absence of venous reflux in both the common femoral and popliteal vein and a low clinical score excluded previous thrombosis in 45 (79%) of the 57 DVT- patients (negative predictive value, 78%). Abnormal venous reflux in the isolated common femoral vein did not reliably predict the presence or absence of previous DVT. However, this occurred in only 13 (13%) patients. The PPG determination of venous refilling time did not improve the results obtained with the other tests.Conclusions. The combination of a standardized clinical evaluation with the results of CUS and DUS can reliably diagnose or exclude previous proximal-vein thrombosis in almost 90% of patients with previous episodes of suspected DVT.

Long Term Prognostic Utility of Matrix Metalloproteinase-9 in Patients with Acute Coronary Syndrome – A Systematic Review

2020 ◽  
Vol 21 ◽  
Author(s):  
Anamika Das ◽  
Melvin George ◽  
Durga Jha ◽  
Luxitaa Goenka
Keyword(s):  
Acute Coronary Syndrome ◽  
High Risk ◽  
Matrix Metalloproteinase ◽  
Developed Countries ◽  
Left Ventricular ◽  
Original Research ◽  
Coronary Syndrome ◽  
Potential Biomarker ◽  
Prognostic Utility

Background: Acute coronary syndrome (ACS) is the leading cause for morbidity and mortality in developed countries. Numerous groups have explored single and multiple biomarker strategies to identify diagnostic prognosticators of ACS which will improve our ability to identify high-risk individuals. Matrix metalloproteinase (MMP-9) is one potential biomarker which has been widely studied in ACS. Recent reports have showed the prognostic utility of MMP-9, but due to inconsistent results, it has not been possible to draw firm conclusions. Objective: This review aims to explore the ability of MMP-9 to predict long-term prognosis of ACS. To clarify this issue, we conducted a literature review to provide a comprehensive assessment of MMP-9 levels in ACS patients. Method: We retrieved a total of 1501 articles from PubMed and Google Scholar. After thorough scrutiny, 12 original research articles were found fulfilling the inclusion exclusion criteria. MMP-9’s ability as a biomarker of prognostication post ACS was reviewed. PRISMA guidelines were used for reporting. Result: The results revealed that MMP-9, apart from being an efficient diagnostic biomarker for ACS, helps in predicting the future risk of ACS with disease outcome. Positive correlation was found between plasma MMP-9 and left ventricular remodeling. A positive association was also found between cardiovascular death and higher MMP-9 levels. Conclusion: MMP-9 can be a potential prognostic marker for ACS and aid in identifying high risk patients for intensive management during follow -up.

An Algorithm Combining Analysis-based Blind Compressed Sensing and Nonlocal Low-rank Constraints for MRI Reconstruction

2019 ◽  
Vol 15 (3) ◽  
pp. 281-291 ◽  
Author(s):  
Mei Sun ◽  
Jinxu Tao ◽  
Zhongfu Ye ◽  
Bensheng Qiu ◽  
Jinzhang Xu ◽  
...  
Keyword(s):  
Compressed Sensing ◽  
Signal Reconstruction ◽  
Low Rank ◽  
Mr Images ◽  
Scanning Time ◽  
Previous State ◽  
Rank Approximation ◽  
Mri Reconstruction ◽  
Magnetic Resonance Imaging Mri ◽  
Rank Constraints

Background: In order to overcome the limitation of long scanning time, compressive sensing (CS) technology exploits the sparsity of image in some transform domain to reduce the amount of acquired data. Therefore, CS has been widely used in magnetic resonance imaging (MRI) reconstruction. </P><P> Discussion: Blind compressed sensing enables to recover the image successfully from highly under- sampled measurements, because of the data-driven adaption of the unknown transform basis priori. Moreover, analysis-based blind compressed sensing often leads to more efficient signal reconstruction with less time than synthesis-based blind compressed sensing. Recently, some experiments have shown that nonlocal low-rank property has the ability to preserve the details of the image for MRI reconstruction. Methods: Here, we focus on analysis-based blind compressed sensing, and combine it with additional nonlocal low-rank constraint to achieve better MR images from fewer measurements. Instead of nuclear norm, we exploit non-convex Schatten p-functionals for the rank approximation. </P><P> Results & Conclusion: Simulation results indicate that the proposed approach performs better than the previous state-of-the-art algorithms.

ARTICULATORY FEATURES OF THE /I/-TYPE VOWELS IN THE ALTAI-KIZHI DIALECT (MRI DATA)

2020 ◽  
pp. 43-50
Author(s):  
ALBINA A. DOBRININA ◽  
Keyword(s):  
Magnetic Resonance Imaging ◽  
Experimental Data ◽  
Magnetic Resonance ◽  
Native Speakers ◽  
Literary Language ◽  
Resonance Imaging ◽  
Articulatory Features ◽  
The Common ◽  
Magnetic Resonance Imaging Mri ◽  
Rural Locality

The paper considers some articulatory features of allophones of the vowel /i/ in the Altai-Kizhi dialect (spoken in the locality Ust-Kan, Altai) of the Altai language visualized by magnetic resonance imaging (MRI). The Altai-Kizhi is the central basic dialect of the Altai literary language. In Altai, each rural locality represents a unique dialect, whose relevance of studying was emphasized by V. V. Radlov. Speech sounds of the /i/-type in the dialects of the Altai language are realized mainly as front variants with different degrees of openness. In the written Altai speech, the symbol “и” is used to denote narrow front non-labialized vowel; some variants of the Altai vowel /i/ are central-back differing in this from the Russian vowel /i/. Experimental data on the territorial dialects of the Altai-Kizhi dialect, obtained from its 6 native speakers (d1-d6) taking into account variable inherent palate height, shows both the common articulation bases of native speakers (clearly-expressed frontness) and their differences (variable openness).

scholarly journals Laparoscopic surgical management of a mature presacral teratoma: a case report

2019 ◽  
Vol 5 (1) ◽  
Author(s):  
Liming Wang ◽  
Yasumitsu Hirano ◽  
Toshimasa Ishii ◽  
Hiroka Kondo ◽  
Kiyoka Hara ◽  
...  
Keyword(s):  
Laparoscopic Resection ◽  
Mature Teratoma ◽  
Skin Incision ◽  
Histopathological Diagnosis ◽  
Tailgut Cyst ◽  
Resonance Imaging ◽  
Presumptive Diagnosis ◽  
Case Presentation ◽  
Contrast Enhanced ◽  
Magnetic Resonance Imaging Mri

Abstract Background Mature presacral (retrorectal) teratoma is very rare. We report a case in which a mature retrorectal teratoma in an adult was successfully treated with laparoscopic surgery. Case presentation A 44-year-old woman was diagnosed with a presacral tumor during a physical examination. Endoscopic ultrasonography (EUS) revealed a multilocular cystic lesion; the lesion was on the left side of the posterior rectum and measured approximately 30 mm in diameter on both contrast-enhanced pelvic computed tomography (CT) and magnetic resonance imaging (MRI). The presumptive diagnosis was tailgut cyst. However, the histopathological diagnosis after laparoscopic resection was mature teratoma. It is still difficult to preoperatively diagnose mature retrorectal teratomas. Conclusions Laparoscopic resection of mature retrorectal teratomas is a feasible and promising method that is less invasive and can be adapted without extending the skin incision.

scholarly journals Endoscopic Study of the Oral and Pharyngeal Cavities in the Common Dolphin, Striped Dolphin, Risso’s Dolphin, Harbour Porpoise and Pilot Whale: Reinforced with Other Diagnostic and Anatomic Techniques

Animals ◽  
2021 ◽  
Vol 11 (6) ◽  
pp. 1507
Author(s):  
Álvaro García de los Ríos y Loshuertos ◽  
Marta Soler Laguía ◽  
Alberto Arencibia Espinosa ◽  
Francisco Martínez Gomariz ◽  
Cayetano Sánchez Collado ◽  
...  
Keyword(s):  
Oral Cavity ◽  
Common Dolphin ◽  
Resonance Imaging ◽  
Pilot Whale ◽  
Anatomical Structures ◽  
Vascular Plexus ◽  
Endoscopic Study ◽  
Main Technique ◽  
The Common ◽  
Magnetic Resonance Imaging Mri

In this work, the fetal and newborn anatomical structures of the dolphin oropharyngeal cavities were studied. The main technique used was endoscopy, as these cavities are narrow tubular spaces and the oral cavity is difficult to photograph without moving the specimen. The endoscope was used to study the mucosal features of the oral and pharyngeal cavities. Two pharyngeal diverticula of the auditory tubes were discovered on either side of the choanae and larynx. These spaces begin close to the musculotubaric channel of the middle ear, are linked to the pterygopalatine recesses (pterygoid sinus) and they extend to the maxillopalatine fossa. Magnetic Resonance Imaging (MRI), osteological analysis, sectional anatomy, dissections, and histology were also used to better understand the function of the pharyngeal diverticula of the auditory tubes. These data were then compared with the horse’s pharyngeal diverticula of the auditory tubes. The histology revealed that a vascular plexus inside these diverticula could help to expel the air from this space to the nasopharynx. In the oral cavity, teeth remain inside the alveolus and covered by gums. The marginal papillae of the tongue differ in extension depending on the fetal specimen studied. The histology reveals that the incisive papilla is vestigial and contain abundant innervation. No ducts were observed inside lateral sublingual folds in the oral cavity proper and caruncles were not seen in the prefrenular space.

Sign in / Sign up

Export Citation Format

Share Document