Different Types Of Lesions Research Articles

High-Definition Ultrasound Characterization of Squamous Carcinoma of the Tongue: A Descriptive Observational Study.

Simple SummaryThe application of high-frequency ultrasound in the oral cavity for malignant lesions is a growing trend. As with other parts of the body, this method could become routine in the future. With this in mind, this work aimed to characterize squamous tumors of the tongue ultrasonographically and added additional descriptive elements to the current literature.High-definition ultrasonography is a diagnostic tool that uses sound echoes to produce images of tissues and organs. In the head and neck region, ultrasounds have been used to diagnose different types of lesions. The intraoral approach was shown to be a real-time, non-invasive way to characterize oral lesions. The tongue is the most often examined region because of its accessibility. This observational study aimed to describe the qualitative characteristics of tongue squamous cell carcinoma images obtained with high-definition intraoral ultrasound by comparing them with the corresponding histopathological sample. Twenty patients were enrolled in this study. The scans of the lesions were carried out with an 18 MHz linear ultrasound probe following the long axis of the lesion. For each lesion, five frames were selected, on which descriptive analysis was performed. A histological sample was taken and then compared to the ultrasonographic acquisition. The sonographic appearance of the tissue layers has a good correlation between ultrasound and histological morphology, and it was easy to distinguish the tumor from the homogenous composition of the tongue tissues. Furthermore, a correlation between the structure by section and pattern of tumor margin features by ultrasound was obtained. Intraoral ultrasonography appears to be a promising technique in the non-invasive characterization of tongue squamous cell carcinoma. Further studies will be needed to improve the technique in terms of ergonomics and repeatability.

ESTUDIO DE MEDIOS DIFUSIVOS CON HETEROGENEIDADES DE BAJO SCATTERING

Biological tissues have the particularity of allowing light between 600 and 900 nm, within a range called optical window, to penetrate them a few centimeters. This characteristic arouses interest in the near-infrared light for its use as a diagnosis tool, with the characteristic of being non-invasive, its application in breast diagnosis is of particular interest for this study. These tissues do not allow the propagation of light in this spectral range in a rectilinear manner, but rather appear as diffusive, thus deteriorating the spatial resolution of the images that can be obtained from them. In this way, it is necessary to develop experimental techniques and specific data analysis strategies in order to obtain optical information from them. Breast tissue can suffer different types of lesions, such as tumors or cysts. This work presents the study of phantoms, which reproduce their optical properties with inclusions that represent tumors and/or cysts, analyzing the influence of the latter, which optical characteristics are non-diffusive, on optical images and the transport of light in these media. The main objective of this work is focused on the 3D localization and optical characterization of translucent heterogeneities in turbid media.

Expression of ezrin protein and phosphorylated ezrin in pelvic endometriotic lesions

ObjectiveTo evaluate the expression of Ezrin and Phosphorylated Ezrin (Phospho-Ezrin) in endometriosis lesions and its relation to the menstrual cycle phase, stage of endometriosis, histological classification, and clinical symptoms. Material and methodsThe authors conducted a retrospective study, with endometriotic lesions collected from women with endometriosis (n = 57) who underwent laparoscopy from 2017 to 2018. The expression of Ezrin and Phosphorylated Ezrin proteins was analyzed by immunohistochemistry. ResultsAll the endometriotic lesions contained immunostaining for Ezrin in the glands. Phosphorylated Ezrin was expressed in the stroma of all endometriotic lesions. There was no difference in the Ezrin and Phosphorylated Ezrin's expression in the retrocervical, ovarian, superficial, and intestinal lesions in the same patient. Dysmenorrhea, dyspareunia, acyclic pain, infertility, and dysuria were similar in the three groups of Ezrin staining. There was an inversely proportional relationship between severe dyschezia and Ezrin's intensity, being 66.7% of Ezrin 1 (weak intensity), 36.7 Ezrin 2 (moderate intensity), and 10.0% of Ezrin 3 (p = 0.013). Regarding Phospho-Ezrin there wasn't a significant difference between all the analyzed variables. Histological classification and menstrual cycle phase had also no significant difference between Ezrin and Phospho-Ezrin immunostaining. ConclusionEzrin protein and Phospho-Ezrin can be considered important markers to elucidate the mechanisms related to migration and attachment of endometriotic lesions. It is still unclear if Ezrin and Phospho-Ezrin are a cause or consequence of endometriosis. Further studies comparing different types of lesions and eutopic endometrium are necessary to elucidate the role of these proteins in the pathogenesis of endometriosis.

Quantitative Assessment of Iodine Intensity of Different Types of Lesions in the Low-Energy (LE) Images of Contrast-Enhanced Spectral Mammography (CESM)

Purpose: To assess the iodine enhancement intensity of breast lesions in low energy (LE) images obtained in contrast-enhanced spectral mammography (CESM) with different tissue compositions. Materials and Methods: A 50 mm dedicated phantom with different lesion insert and iodine insert were used to assess the enhancement intensity quantitatively. The target slab of the phantom consists of three lesions + iodine inserts together and 100% adipose equivalent,100% glandular equivalent inserts alone to mimic the adipose and glandular lesion without contrast-enhancement. Each iodine inserts having a concentration of 0.5 mgI/cm3, 1.0 mgI/cm3, 2.0 mgI/cm3. The phantom was exposed under semiautomated function at 28 kV, 30 kV, and 32 kV with Mo/Rh target/filter combination. Iodine intensity was estimated for three types of lesions at three breast equivalent compositions. Results: Lesions with fatty tissue had high intensity while lesions with glandular tissues had the minimum intensity. Among fatty lesions, highest mean intensity value (0.972±0.003) observed with minimum iodine concentration (F + 0.5 mgI/cm3). The highest mean intensity value (0.882±0.001) was found related to the glandular lesion with maximum iodine concentration (G + 2.0 mgI/cm3). The one-way ANOVA statistical test confirmed that mean intensity values were significantly varied among different lesions (P < 0.05). Conclusion: LE images obtained in CESM can be used to identify the different types of lesions without performing the full field digital mammography (FFDM) as an additional examination prior to the CESM procedure.

Automatic Image Characterization of Psoriasis Lesions

Psoriasis is a chronic skin disease that affects 125 million people worldwide and, particularly, 2% of the Spanish population, characterized by the appearance of skin lesions due to a growth of the epidermis that is seven times larger than usual. Its diagnosis and monitoring are based on the use of methodologies for measuring the severity and extent of these spots, and this includes a large subjective component. For this reason, this paper presents an automatic method for characterizing psoriasis images that is divided into four parts: image preparation or pre-processing, feature extraction, classification of the lesions, and the obtaining of parameters. The methodology proposed in this work covers different digital-image processing techniques, namely, marker-based image delimitation, hair removal, nipple detection, lesion contour detection, areal-measurement-based lesion classification, as well as lesion characterization by means of red and white intensity. The results obtained were also endorsed by a professional dermatologist. This methodology provides professionals with a common software tool for monitoring the different existing typologies, which proved satisfactory in the cases analyzed for a set of 20 images corresponding to different types of lesions.

Application of Artificial Intelligence Technology in Automatic Detec-tion of large Intestine Polyps

<div><p class="4"><strong>Objective:</strong> to establish an automatic colonoscopy method based on artificial intelligence. <strong>Methods:</strong> a public database established by a university hospital was used, including colorectal fat and data collection. Initially, all frames in the video are normalized to reduce the high variability between databases. Then, the convolution neural network is used for full depth learning to complete the detection task of polyps. The network starts with the weights learned from millions of natural images in the ImageNet database. According to the fine-tuning technology, the colonoscopy image is used to update the network weight. Finally, the detection of polyps is performed by assigning the probability of containing Po ́ lipo to each table and determining the threshold defined when polyps appears in the table. <strong>Results:</strong> 1875 cases were collected from 5 public databases and databases established by university hospitals, with a total of 123046 forms. The method was trained and evaluated. Comparing the results with the scores of different colonoscopy experts, the accuracy was 0.77, the sensitivity was 0.89, the specificity was 0.71, and the ROC curve (re ceiver operation characteristics) was 0.87. <strong>Conclusion:</strong> compared with experienced gastrointestinal markers, this method overcomes the high variability of different types of lesions and different colonic light conditions (handle, folding or contraction), has very high sensitivity, and can reduce human errors, which is one of the main factors leading to the non detection or leakage of Po lipids in colonoscopy.</p></div>

Role of multidetector ct in quantitative enhancement- washout analysis of solid renal masses

BackgroundEnhancement washout technique in solid renal masses using multidetector computed tomography (MDCT) can differentiate different type of lesions. 99 Patients who are presenting with suspected renal masses or renal tumour for staging are included in this study. CT examination are carried out at urology and nephrology centre using MDCT. The attenuation values (Hounsfield Unit) will be assesed for each lesion on the pre enhanced, corticomedullary, nephrographic and delayed phases. Washout ratio will be calculated for each phase of enhancement in comparison to the unenhanced attenuation value. The characteristics of enhancement-washout will be correlated with the final histopathological diagnosis.ResultsEarly enhancement and washout pattern was noted in 54 renal lesions (54.5%) representing 4 types of renal lesions; Oncocytoma (n = 13), clear cell renal cell carcinoma (n = 16), Chromophobe renal cell carcinoma (n = 15) and unclassified renal cell carcinoma (n = 10).Prolonged enhancement pattern was noted 45 lesions (45.4%); PRCC (n = 14), 10 case of lipid poor AML (n = 10), metanephric adenoma (n = 10) and Xp11 RCC (n = 11). High pre-contrast attenuation was noted in Xp 11RCC showing attenuation value 41.7 ± 6.823HU. The highest CMP values were noted in CCRCC (151.9 ± 20.4) followed by oncocytomas (137.6 ± 19.15HU) and then CHRCC (123.6 ± 16.6 HU)while the lowest values were noted in Metanephric adenoma)57.1 ± 17.4HU)and followed by PRCC (59.9 ± 4.8)and followed by lipid poor AML (79.17 ± 13.666) and RCC unclassified (89.06 ± 18.1).ConclusionsFour-phase MDCT (the unenhanced, corticomedullary, nephrographic, and excretory phases) evaluate role of MDCT in differentiation of solid renal masses.

Distinct Transcriptional Programs Underlie Differences in Virulence of Isolates on Host Plants in a Fungal Pathogen, Colletotrichum gloeosporioides.

Susceptible host plants challenged by fungal pathogens can display different types of lesions, which can be attributed to environmental factors affecting the nature of interactions between the host and pathogen. During our survey of apple anthracnose in Korea, two distinct types of disease symptoms, designated as progressive (PS) and static symptoms (SS), were recognized. PS is a typical, rapidly enlarging symptom of apple anthracnose, while SS is a small, dark speck that does not expand further until the harvesting season. Isolation and genotyping of pathogens from disease lesions suggested that all of them belong to Colletotrichum gloeosporioides, a well-known causal agent of apple anthracnose. Two types of isolates were comparable in growth on media, spore germination and appressorium formation, virulence test on fruits at various temperature conditions. Furthermore, they were analyzed at the molecular level by a phylogenetic tree, RNA-seq, and expression of virulence gene. However, the SS isolates were defective in appressorium-mediated penetration into the underlying substratum. RNA-seq analysis of PS and SS isolates showed that distinct transcriptional programs underlie the development of different types of anthracnose symptoms in host plants. One downregulated gene in SS encoded isocitrate lyase is essential for disease development via its involvement in the glyoxylate cycle. It partly explains why SS is less virulent than PS on host plants. Overall, our work challenges the traditional view on the development of different lesion types and provides valuable insights into variations that exist in the pathogen population.

An interpretable machine learning model to explain the interplay between brain lesions and cortical atrophy in multiple sclerosis.

Multiple Sclerosis (MS) is the most common cause, (after trauma) of neurological disability in young adults in Western countries. While several Magnetic Resonance Imaging (MRI) studies have demonstrated a strong association between the presence of cortical grey matter atrophy and the progression of neurological impairment in MS patients, the neurobiological substrates of cortical atrophy in MS, and in particular its relationship with white matter (WM) and cortical lesions, remain unknown. The aim of this study was to investigate the interplay between cortical atrophy and different types of lesions at Ultra-High Field (UHF) 7 T MRI, including cortical lesions and lesions with a susceptibility rim (a feature which histopathological studies have associated with impaired remyelination and progressive tissue destruction). We combined lesion characterization with a recent machine learning (ML) framework which includes explainability, and we were able to predict cortical atrophy in MS from a handful of lesion-related features extracted from 7 T MR imaging. This highlights not only the importance of UHF MRI for accurately evaluating intracortical and rim lesion load, but also the differential contributions that these types of lesions may bring to determine disease evolution and severity. Also, we found that a small subset of features [WM lesion volume (not considering rim lesions), patient age and WM lesion count (not considering rim lesions), intracortical lesion volume] carried most of the prediction power. Interestingly, an almost opposite pattern emerged when contrasting cortical with WM lesion load: WM lesion load is most important when it is small, whereas cortical lesion load behaves in the opposite way.Clinical Relevance- Our results suggest that disconnection and axonal degeneration due to WM lesions and local cortical demyelination are the main factors determining cortical thinning. These findings further elucidate the complexity of MS pathology across the whole brain and the need for both statistical and mechanistic approaches to understanding the etiopathogenesis of lesions.

Values of Contrast-Enhanced Ultrasound in Classification and Diagnosis of Common Bile Duct and Superficial Organ Lesions under Compression Algorithm.

This work aimed to investigate values of contrast-enhanced ultrasound (CEUS) under DEFLATE in the classification and diagnosis of the common bile duct and superficial lymphoid lesions. 88 patients with lower common bile duct lesions and 126 patients with superficial lymphoid lesions were selected as the subjects investigated and examined by CEUS under DEFLATE to compare characteristics and diagnostic efficiency of CEUS in different types of lesions. The time-intensity curve (TIC) was for quantitative analysis on CEUS results. The results showed that there were statistically significant differences in the comparison of time to peak (TTP), area under the curve (AUC), and gradient (Grad) of common bile duct walls in patients from the malignant group (P < 0.05), while the comparison of three indicators of patients in the benign group was not statistically remarkable (P > 0.05). In addition, there were statistically great differences in TTP, AUC, and Grad among patients in the benign and malignant groups (P < 0.05). The sensitivity, specificity, accuracy, and positive/negative predictive value of CEUS + ultrasound (US) in the diagnosis of benign and malignant lymph nodes were 92.83%, 87.14%, 89.54%, 91.23%, and 86.43%, respectively. The values of maximal intensity (Imax) in the reactive hyperplasia group (group A), lymphoma group (group B), and metastatic lymph nodes group (group C) were compared, showing statistical differences (P < 0.05). The TTP and AUC of group B were higher than those of groups A and C, respectively (P < 0.05), and the base-to-peak ascending slope (KUP) and the absolute value of the semidescending slope (KDOWN) in group C increased hugely compared to group A (P < 0.05). It indicated that CEUS examination under DEFLATE could be applied in the qualitative diagnosis of lower common bile duct lesions and superficial lymphoid lesions, which was worthy of clinical application.

An optimal deep learning framework for multi-type hemorrhagic lesions detection and quantification in head CT images for traumatic brain injury.

Traumatic Brain Injury (TBI) could lead to intracranial hemorrhage (ICH), which has now been identified as a major cause of death after trauma if it is not adequately diagnosed and properly treated within the first 24 hours. CT examination is widely preferred for urgent ICH diagnosis, which enables the fast identification and detection of ICH regions. However, the use of it requires the clinical interpretation by experts to identify the subtypes of ICH. Besides, it is unable to provide the details needed to conduct quantitative assessment, such as the volume and thickness of hemorrhagic lesions, which may have prognostic importance to the decision-making on emergency treatment. In this paper, an optimal deep learning framework is proposed to assist the quantitative assessment for ICH diagnosis and the accurate detection of different subtypes of ICH through head CT scan. Firstly, the format of raw input data is converted from 3D DICOM to NIfTI. Secondly, a pre-trained multi-class semantic segmentation model is applied to each slice of CT images, so as to obtain a precise 3D mask of the whole ICH region. Thirdly, a fine-tuned classification neural network is employed to extract the key features from the raw input data and identify the subtypes of ICH. Finally, a quantitative assessment algorithm is adopted to automatically measure both thickness and volume via the 3D shape mask combined with the output probabilities of the classification network. The results of our extensive experiments demonstrate the effectiveness of the proposed framework where the average accuracy of 96.21 percent is achieved for three types of hemorrhage. The capability of our optimal classification model to distinguish between different types of lesion plays a significant role in reducing the false-positive rate in the existing work. Furthermore, the results suggest that our automatic quantitative assessment algorithm is effective in providing clinically relevant quantification in terms of volume and thickness. It is more important than the qualitative assessment conducted through visual inspection to the decision-making on emergency surgical treatment.

Pericyte-derived fibrotic scarring is conserved across diverse central nervous system lesions

Fibrotic scar tissue limits central nervous system regeneration in adult mammals. The extent of fibrotic tissue generation and distribution of stromal cells across different lesions in the brain and spinal cord has not been systematically investigated in mice and humans. Furthermore, it is unknown whether scar-forming stromal cells have the same origin throughout the central nervous system and in different types of lesions. In the current study, we compared fibrotic scarring in human pathological tissue and corresponding mouse models of penetrating and non-penetrating spinal cord injury, traumatic brain injury, ischemic stroke, multiple sclerosis and glioblastoma. We show that the extent and distribution of stromal cells are specific to the type of lesion and, in most cases, similar between mice and humans. Employing in vivo lineage tracing, we report that in all mouse models that develop fibrotic tissue, the primary source of scar-forming fibroblasts is a discrete subset of perivascular cells, termed type A pericytes. Perivascular cells with a type A pericyte marker profile also exist in the human brain and spinal cord. We uncover type A pericyte-derived fibrosis as a conserved mechanism that may be explored as a therapeutic target to improve recovery after central nervous system lesions.

Treatment of keloids and hypertrophic scars. Position statement of the Brazilian expert group GREMCIQ.

Keloids (K) and hypertrophic scars (HS) are abnormal responses to wound healing that occur as the result of dermal inflammation. Despite the advances on their treatment, many patients still suffer from the negative effects of excessive scarring; its approach is impaired by the lack of objective data on different treatments and the large genetic variability among patients and the difficulties in producing multicentre studies. Their incidence among the Brazilian population is high, as the result of an admixture of Amerindians, Europeans and Africans ancestral roots. With the aim of producing multicentre studies on K and HS, a panel of senior Brazilian dermatologists focused on their treatment was invited to contribute with the K and HS Treatment Brazilian Guidelines. In the first part of this study, different treatment modalities for keloids and HS are fully reviewed by the panel. The second part of the study presents a consensus recommendation of treatment for different types of lesions. More than a literature review, this article aims to show the pitfalls and pearls of each therapeutic option, as well as a therapeutic approach by the Panelof Experts on keloids and Scars on a highly mixed population, providing simple guidelines.

Diagnostic value of different color ultrasound diagnostic method in endometrial lesions

BACKGROUNDEndometrial lesions include endometrial cancer and inferior fibroids. Among them, endometrial cancer as a malignant tumor seriously endangers the life and health of patients. Ultrasonography is an important means of diagnosing female reproductive system diseases, and it is of critical value for the early diagnosis of endometrial cancer. However, different ultrasound inspection programs have achieved different results. It is of great significance to choose a suitable inspection program.AIMTo explore the diagnostic efficacy of different ultrasonic examination methods in clinical endometrial lesions.METHODSThe 140 patients with endometrial lesions who were treated in our hospital from April 2018 to October 2019 were used as the research subjects. All patients underwent transvaginal color ultrasound and transabdominal color ultrasound. We compared the diagnostic coincidence and image display effects of the two different examination methods, and the endometrial thickness, blood flow, uterine effusion and resistance index of different diseases were observed by transvaginal color ultrasound.RESULTSThe diagnostic coincidence rate of all types of diseases of transvaginal color ultrasound was significantly higher than that of transabdominal color ultrasound (P = 0.001, 0.005, 0.001 and 0.001). In addition, the excellent and good rate of image display of transvaginal color ultrasound was higher than that of transabdominal color ultrasound (P = 0.001). There were significant differences in endometrial thickness in patients with different types of endometrial lesions through the transvaginal color examination (P = 0.001). The incidence rate of uterine effusion in patients with endometrial carcinoma was significantly higher than that in patients with other types of endometrial lesions (P = 0.001), and the rate of the blood flow was the highest (P = 0.001). The comparison of blood flow resistance index indicated that the blood flow resistance index in endometrial cancer patients was the lowest, which shows that the difference was statistically significant (P = 0.001).CONCLUSIONThe overall diagnostic efficacy of transvaginal color ultrasound in the clinical diagnosis of endometrial lesions is better than that of transabdominal color ultrasound, which held higher diagnostic coincidence rate and image display effect. There were significant differences in the thickness of the endometrium and the blood flow in different types of lesions.

History, Variations, and Extensions of the Retrosigmoid Approach: Anatomical and Literature Review.

The retrosigmoid approach is the workhorse for posterior fossa surgery. It gives a versatile corridor to tackle different types of lesions in and around the cerebellopontine angle. The term "extended" has been used interchangeably in the literature, sometimes creating confusion. Our aim was to present a thorough analysis of the approach, its history, and its potential extensions. Releasing cerebrospinal fluid from the subarachnoid spaces and meticulous microsurgical techniques allowed for the emergence of the retrosigmoid approach as a unilateral variation of the traditional suboccipital approach. Anatomical landmarks are helpful in localizing the venous sinuses and planning the craniotomy, and Rhoton's rule of three is the key to unlock difficult neurovascular relationships. Extensions of the approach include, among others, the transmastoid, supracerebellar, far-lateral, jugular foramen, and perimeatal approaches. The retrosigmoid approach applies to a broad range of pathologies and, with its extensions, can provide adequate exposure, obviating the need for extensive and complicated approaches.

Meniscal ramp lesions: diagnostic performance of MRI with arthroscopy as reference standard

BackgroundThe posteromedial meniscal region is gaining interest among orthopedic surgeons, as lesions of this area has been reported to be significantly associated with anterior cruciate ligament tears. The current imaging literature is unclear.PurposeTo evaluate the diagnostic performance of MR in the detection of meniscal ramp lesions having arthroscopy as reference standard.Materials and methodsWe retrospectively included 56 patients (mean age of 25 ± 7 years; 14 females) from January to November 2017 with a arthroscopically proved ACL tear and posterior meniscocapsular separation. On preoperative MRI, two radiologists with 13 and 2 years’ experience in musculoskeletal imaging assessed the presence/absence of ramp lesion, meniscotibial ligament lesion, peripheral meniscal lesion, or their combination, bone bruise. Having arthroscopy as reference standard, diagnostic performance of MRI in the evaluation of ramp area lesions was calculated. Cohen’s kappa (k) and Fisher's Exact Test statistics were used.ResultsAgreement between radiologists ranged from κ = 0.784 (meniscotibial ligament lesions) to κ = 0.918 red–red meniscal lesion. Sensitivities were 97.4% for ramp lesions, 95.8% for meniscotibial ligament lesion, 94.4% for peripheral meniscal lesions; specificities were 88.9%, 81.3%, and 97.4%, respectively; accuracies were 94.6%, 87.5%, and 96.4%, respectively. Agreement between MR and arthroscopy was almost perfect in identification of ramp lesions (κ = 0.871) and red–red zone meniscal lesions (κ = 0.908). The agreement between the two methods was substantial (κ = 0.751) for meniscotibial lesion. No significant association between tibial plateau bone bruise and the different type of lesions was found (κ ≥ 0.004 and p ≥ 0.08).ConclusionMR has high diagnostic performance in meniscal ramp area lesion assessment, with substantial to almost perfect inter-reader agreement.

Multi-class segmentation of skin lesions via joint dictionary learning

Melanoma is the deadliest type of human skin cancer. However, it is curable if diagnosed in an early stage. Recently, computer aided diagnosis (CAD) systems have drawn much interests. Segmentation is a crucial step of a CAD system. There are different types of skin lesions having high similarities in terms of color, shape, size and appearance. Most available works focus on a binary segmentation. Due to the huge variety of skin lesions and high similarities between different types of lesions, multi-class segmentation is still a challenging task. Here, we propose a method based on joint dictionary learning for multi-class segmentation of dermoscopic images. The key idea is based on combining data from different feature spaces to build a more informative structure. We consider training data from two different spaces. Then, two dictionaries are jointly learned using the K-SVD algorithm. The final segmentation is accomplished by a graph-cut method based on both the topological information of lesions and the learned dictionaries. We evaluate our proposed method on the ISIC 2107 dataset to segment three classes of lesions. Our method achieves better results, specially for challenging skin lesions, compared to the only available method for multi-class segmentation of dermoscopic images. We also evaluate the performance of our method for binary segmentation and lesion diagnosis and compared the results with the other state-of-the-art methods. Experimental results show the efficiency and effectiveness of the proposed method in producing results that are more reliable for clinical applications, even using limited amount of training data.

Approach to Mitral Valve Repair in Infective Endocarditis: Single Center, Single Surgeon, Cross Sectional Study

Objective: The traditional approach was to replace the mitral valve on infective endocarditis when the response to antibiotic therapy is poor. The decision to repair the mitral valve (MV) in this setting is more challenging. This study analysed the different approaches adopted to perform a successful repair. Methods: This retrospective cross sectional study composed of all the patients referred to a single surgeon at Kandy National Hospital, Sri Lanka over a period from June 2011 to August 2020. Repair of MV in every case was the primary approach. Different types of lesion found on direct visual assessment, techniques adopted and outcome of MV repair in native MV infective endocarditis were analysed. Results: Total number of cases was 23, (16 males, 7 females) with a mean age of 42 years. MV repair was successful in all (95%) except one case, as per the intra-operative assessment made (saline test and trans esophageal echocardiography). Vegetation or leaflet perforation were the most common lesions (Posterior mitral valve leaflet/PMVL: 18, Anterior leaflet/AMVL: 7) followed by chordal rupture (6). The table shows the repair strategies used. One death occurred on postoperative third day following MV repair due to rupture of cerebral mycotic aneurysm. 22 patients were discharged home with satisfactory pre-discharge transthoracic 2D echocardiography. Conclusions: The study shows successful repair of MV on infective endocarditis is possible in majority of cases with skilled modulation of surgical approach to individual patient pathology found at the time of surgery. Long term follow-up data requires for the assessment of durability of this approach. Procedure Number Annuloplasty ring (flexible, rigid) 22 Pericardial patchAMVLPMVL 12 Folding plasty 2 Neochords 5 Triangular resection and repairAMVLPMVL 12 Quadrangular resection and repairAMVLPMVL 50 Resection and slidingplastyAMVLPMVL 26

Simulating lesion-dependent functional recovery mechanisms

Functional recovery after brain damage varies widely and depends on many factors, including lesion site and extent. When a neuronal system is damaged, recovery may occur by engaging residual (e.g., perilesional) components. When damage is extensive, recovery depends on the availability of other intact neural structures that can reproduce the same functional output (i.e., degeneracy). A system’s response to damage may occur rapidly, require learning or both. Here, we simulate functional recovery from four different types of lesions, using a generative model of word repetition that comprised a default premorbid system and a less used alternative system. The synthetic lesions (i) completely disengaged the premorbid system, leaving the alternative system intact, (ii) partially damaged both premorbid and alternative systems, and (iii) limited the experience-dependent plasticity of both. The results, across 1000 trials, demonstrate that (i) a complete disconnection of the premorbid system naturally invoked the engagement of the other, (ii) incomplete damage to both systems had a much more devastating long-term effect on model performance and (iii) the effect of reducing learning capacity within each system. These findings contribute to formal frameworks for interpreting the effect of different types of lesions.

Role of Diffusion-Weighted Magnetic Resonance Imaging inDetecting and Characterizing Benign and Malignant LiverTumors in Adults

AbstractBackground: DWI is done by quantifying the amount ofdiffusion through tissues and calculating ADC values. Tumors,which consist of excessive proliferation of cells, wouldexpectantly show restricted diffusion. ADC values can aid incharacterizing focal liver lesions as benign vs. malignant.DWI when used in combination with dynamic MRI can beused to enhance the accuracy of liver lesion characterizationand diagnosis.Aim of Study: To assess the role of diffusion-weightedmagnetic resonance imaging (DWI) in detection and charac-terization of hepatic focal lesions, and its value in differenti-ating benign from malignant masses.Patients and Methods: A total of 60 liver disease patients (21 males and 39 females) with ages ranged from 20 to 63years old were included in the study. All of the patientsunderwent MRI examination including pre-contrast imaging,dynamic study and diffusion study. The morphological featuresof each lesion were recorded and diffusion images werereviewed for final radiological characterization and detection of focal lesions. ADC values were calculated for all patients.Results: This study included 60 patients with varioustypes of lesions, 40 of which had benign lesions and 20 withmalignant lesions. The diffusion images aided in diagnosisof malignant lesions with different components. AbsoluteADC values of different types of lesions were not similar.Benign hepatic lesions have generally higher ADC valuescompared with malignant lesions. The ADC values we foundfor different lesions were consistent with previous studies.Conclusion: Diffusion-weighted MRI sequence withquantitative ADC measurement should be used as an additionalsequence to supplement conventional MRI protocol studiesfor proper detection and characterization of solid liver lesions.