Algebraic topology-based machine learning using MRI predicts outcomes in primary sclerosing cholangitis.

BACKGROUND: Primary sclerosing cholangitis (PSC) is a chronic cholestatic liver disease that can lead to cirrhosis and hepatic decompensation. However, predicting future outcomes in patients with PSC is challenging. Our aim was to extract magnetic resonance imaging (MRI) features that predict the development of hepatic decompensation by applying algebraic topology-based machine learning (ML). METHODS: We conducted a retrospective multicenter study among adults with large duct PSC who underwent MRI. A topological data analysis-inspired nonlinear framework was used to predict the risk of hepatic decompensation, which was motivated by algebraic topology theory-based ML. The topological representations (persistence images) were employed as input for classification to predict who developed early hepatic decompensation within one year after their baseline MRI. RESULTS: We reviewed 590 patients; 298 were excluded due to poor image quality or inadequate liver coverage, leaving 292 potentially eligible subjects, of which 169 subjects were included in the study. We trained our model using contrast-enhanced delayed phase T1-weighted images on a single center derivation cohort consisting of 54 patients (hepatic decompensation, n = 21; no hepatic decompensation, n = 33) and a multicenter independent validation cohort of 115 individuals (hepatic decompensation, n = 31; no hepatic decompensation, n = 84). When our model was applied in the independent validation cohort, it remained predictive of early hepatic decompensation (area under the receiver operating characteristic curve = 0.84). CONCLUSIONS: Algebraic topology-based ML is a methodological approach that can predict outcomes in patients with PSC and has the potential for application in other chronic liver diseases.

Niacin Status Indicators and Their Relationship with Metabolic Parameters in Dairy Cows during Early Lactation.

Previous experimental models on cows have examined the difference in the metabolic adaptation in cows after niacin administration, without identifying the most important mediators between niacin administration and its biological effects, namely active forms of niacin. All tissues in the body convert absorbed niacin into its main metabolically active form, the coenzyme nicotinamide adenine dinucleotide (NAD) and nicotinamide adenine dinucleotide phosphate (NADP). The aim of this study was to determine the influence of niacin administration in periparturient period on NAD, NADP and the NAD:NADP ratio and to determine relationship between these indicators of an active form of niacin with metabolic parameters in cow blood. The study included 90 healthy cows: 45 cows receiving niacin and 45 cows were negative control. The niacin group was treated with nicotinic acid for two weeks before, as well as two weeks after parturition. Nicotinic acid was applied per os with feed. In cows receiving niacin, there was a significantly higher concentration of NAD and NADP, but the NAD:NADP ratio did not differ compared with control. All three indicators were able to separate cows who received and who did not receive additional niacin. NAD and NADP are good indicators of the availability of niacin from additional sources. The NAD:NADP ratio is a good indicator of the biological effect of applied niacin on metabolites in cows due to its correlation with a number of metabolites: positive correlation with glucose, insulin, glucose to insulin ratio and the revised quantitative insulin sensitivity check index (RQUICKIBHB) of insulin resistance, triglycerides and cholesterol, and a negative correlation with nonesterified fatty acid (NEFA), beta hydroxybutyrate (BHB), gamma-glutamyltranspherase (GGT) and urea in cows receiving niacin. The same amount of added niacin in feed can produce different concentrations of NAD, NADP and NAD:NADP in the blood, and this was not related to their concentration before the addition of niacin. The change in the concentration of the active form of niacin (NAD, NADP and NAD:NADP) further correlates with the concentration of metabolic parameters, which indicates that the intensity of the biological effect of additional niacin can be accurately determined only if we know the concentrations of its active forms in blood. Under basal conditions (without additional niacin), active forms of niacin that already exist in the blood do not show significant correlations with metabolic parameters.

A Potential Anthelmintic Phytopharmacological Source of Origanum vulgare (L.) Essential Oil against Gastrointestinal Nematodes of Sheep.

The development of anthelmintic resistance in sheep gastrointestinal nematodes (GINs) requires novel strategies for the sustainable control of these parasites. This study aimed to evaluate the anthelmintic efficacy of the Origanum vulgare (L.) essential oil (EO) against sheep GINs and to evaluate the possibility of its use in control practice. The in vitro egg hatch test was conducted at eight different concentrations (50, 12.5, 3.125, 0.781, 0.195, 0.049, 0.025, and 0.0125 mg/mL) of the tested EO. For the in vivo fecal egg count reduction test, the EO of O. vulgare was administrated orally at a mean single dose of 150 mg/kg to sheep from two farms in Southern Italy, whereby potential toxic effects to the hosts were also evaluated. In the egg hatch test, the inhibition of egg hatchability varied from 71.3% to 93.7%, depending on the concentration used. The high anthelmintic potential was confirmed in the fecal egg count reduction test with an average reduction of nematode eggs in feces of 43.2% and 60.1% on days 7 and 14 after treatment, respectively. In addition, no toxic effects were noticed during the clinical examination of sheep or by observing blood count and liver or kidney function test results. The obtained results suggest the strong activity of the O. vulgare EO against sheep GINs, probably due to a high percentage of carvacrol (76.21%), whereby it can be considered safe for sheep at the dose tested in vivo. Therefore, it is suitable for use in veterinary practice as a part of an integrated strategy for the control of sheep GINs.

The role of the color Doppler ultrasonography and computed tomography in estimation of portal hypertension.

Introduction: Liver diseases with disturbances of hepatic and splanchnic circulation lead to the portal hypertension, with or without a portal vein thrombosis. Objective: This study was based on the testing of hypothesis that more data and more precise diagnosis in patients with disorders of portal circulation can be obtained by using color Doppler ultrasonography (CDU) and computed tomography (CT) with contrast. Methods: The study was conducted from February 2011 to May 2014 and it comprised 120 patients who were suspected to have portal hypertension or already had clinical confirmation of the portal hypertension, patients with hepatitis, and some patients with hematological diseases. The first group of 40 patients was examined by conventional ultrasonography and CDU, the second group by contrast CT, and the third group of patients was examined by both methods (CDU and contrast CT). After six months of adequate therapy, the patients had control examinations with the same diagnostic technique used during their first examination. Results: Retrospective analysis showed that CDU is more sensitive than CT in the assessment of presence and age of thrombi (CDU 93.9%; CT 86.1%). CT gives precise data in detection of portosystemic collaterals. Sensitivity of CT is 100% and its specificity is 67%. Cumulative sensitivity and specificity for most parameters were increased in patients with portal hypertension when both methods were applied. Conclusion: This study emphasizes the possibility of early and more accurate diagnosis achieved when combining two radiological techniques (CDU and contrast CT scan), which is not the case when these methods are used separately.

Hippocampal diffusion tensor imaging microstructural changes in vascular dementia.

To explore microstructural integrity of hippocampus in vascular dementia (VD) using DTI. Twenty-five individuals with VD, without magnetic resonance imaging (MRI) evidence of gray matter pathology, and 25 matched healthy control (HC) individuals underwent a 3T MRI protocol including T2, FLAIR, and PD in the axial plane, 3D whole-brain T1-weighted with an isotropic resolution of 1 mm, and DTI acquired using 64 diffusion sensitizing directions, b value of 1,500 s/mm(2), 65 axial slices, isotropic resolution of 1.8 mm. Images were processed to obtain indices of microstructural variations of bilateral hippocampi. Mean diffusivity (MD) in the hippocampus of patients with VD was significantly increased (p < 0.05) bilaterally with respect to that of the group of HC examinees. In VD group left hippocampal MD (10(-6 )× mm(2)/s) was 833.4 ± 92.8; in HC group left MD was 699.8 ± 56. In VD group, right hippocampal MD was 859.1 ± 69.8; in HC group right MD was 730.4 ± 40.2. No group differences were found in hippocampal FA. DTI shows microstructural hippocampal damage in VD in patients with normal appearing gray matter structures on conventional MRI, indicating the need for further research on the link between VD and AD.

The question is whether hemiparesis is more common in unilateral than bilateral chronic subdural hematoma.

INTRODUCTION: Chronic subdural hematoma is an intracranial hemorrhagic lesion that illustrates various expressions in clinical and radiological practice. The aim of this study was to emphasize the correlation between the brain site of chronic subdural hematoma and clinical symptoms/signs of disease. Furthermore, the study denotes the significance of hemiparesis occurrence in the patients with unilateral chronic subdural hematomas more than in those with bilateral ones, associated with time required to diagnose hematoma. MATERIAL AND METHODS: A three-year study included 72 patients with chronic subdural hematoma. According to their clinical and neurological symptoms on hospital admission, all patients underwent non-contrast brain computed tomography scan, which confirmed the diagnosis. The radiological parameters, including the site of chronic subdural hematoma, a hematoma width and midline shift were recorded to give precise data about the correlation with neurological symptoms. A special focus was put on the lag time between the onset of symptoms and signs to diagnosis of chronic subdural hematoma. RESULTS: The study proved that the patients with unilateral chronic subdural hematoma had more frequent occurrence of hemiparesis than the patients with bilateral chronic subdural hematoma. It took the left-sided chronic subdural hematomas less time (about 200 hours earlier) than the right-sided ones to present its symptoms although the average hematoma diameter value was almost the same. CONCLUSION: The site and the form of intracranial lesion-chronic subdural hematoma could have a great influence on neurological and functional condition in a patient. Although the length of time required for making diagnosis as well as clinical symptoms greatly differ and the latter are not always so clear, physicians should maintain a high level of suspicion for this disease and thus contribute to prompt diagnosis and better clinical outcome of patients.

Blunt chest trauma--an audit of injuries diagnosed by the MDCT examination.

BACKGROUND/AIM: Multidetector computed tomography (MDCT) characterised by speed and precision is increasingly accessible in emergency wards. The aim of our study was to determine the most common injuries to the chest region, as well as type associated extrathoracic injuries, and the treatment outcome. METHODS: This prospective study included 61 patients with blunt trauma who were submitted to computed tomography (CT) of the thorax. The number of injuries was evaluated by organs and organ systems of the chest. The cause of the injury, the length and the outcome of the treatment, and the presence of injuries in other regions were assessed. RESULTS: Chest injuries were associated with injuries to other regions in 80.3% cases, predominantly injuries to extremities or pelvic bones in 54.1% cases, followed by head injuries in 39.3% patients. Associated thoracic injuries were present in 90.9% of patients with lethal outcome. Lung parenchymal lesions, pleural effusions and rib fractures were the most common injuries affecting 77.1%, 65.6% and 63.9% of the cases, respectively. CONCLUSION: Blunt chest trauma is a significant problem affecting predominantly males in their forties and it is usually caused by a motor vehicle accident. In case of pneumomediastinum or mediastinal haematoma, the use of 3D reconstructions is advised for diagnosing possible tracheobronchial ruptures and thoracic aorta injuries. Increased resolution of CT scanners yielded a large number of findings that are occult on radiography, especially in the event of lung parenchymal and pleural injuries. However, none imaging modality can replace surgical judgement.

Blunt trauma of bone structures of the chest--computed tomography vs multidetector computed tomography.

BACKGROUND/AIM: Computerized tomography (CT), especially multidetector CT (MDCT), has had a revolutionary impact in diagnostic in traumatized patients. The aim of the study was to identify and compare the frequency of injuries to bone structures of the thorax displayed with 5-mm-thick axial CT slices and thin-slice (MDCT) examination with the use of 3D reconstructions, primarily multiplanar reformations (MPR). METHODS: This prospective study included 61 patients with blunt trauma submitted to CT scan of the thorax as initial assessment. The two experienced radiologists inde pendently and separately described the findings for 5-mm-thick axial CT slices (5 mm CT) as in monoslice CT examination; MPR and other 3D reconstructions along with thin-slice axial sections which were available in modern MDCT technologies. After describing thin-slice examination in case of disagreement in the findings, the examiners redescribed thin-slice examination together which was ultimately considered as a real, true finding. RESULTS: No statistically significant difference in interobserver evaluation of 5 mm CT examination was recorded (p > 0.05). Evaluation of fractures of sternum with 5 mm CT and MDCT showed a statistically significant difference (p < 0.05) in favor of better display of injury by MDCT examination. CONCLUSION: MDCT is a powerful diagnostic tool that can describe higher number of bone fractures of the chest in traumatized patients compared to 5 mm CT, especially in the region of sternum for which a statistical significance was obtained using MPR. Moreover, the importance of MDCT is also set by easier and more accurate determination of the level of bone injury.

Recurrent longitudinally extensive transversal myelitis in a patient with Sjögren's syndrome.

INTRODUCTION: Longitudinally extensive transverse myelitis (LETM) is a transversal myelitis that extends through three or more vertebral segments in length. CASE REPORT: A 52-year-old woman was hospitalized due to pain in the lumbar region, difficulty in walking, hypoesthesia of the anogenital area and urinary retention. In the past medical history, two years earlier, the patient had been diagnosed with transversal myelitis confirmed by MRI of the cervical spine and six months earlier, the patient was diagnosed with primary Sjögren's syndrome (SS). During the current hospitalization MRM of the spinal cord revealed extensive inflammatory lesions of almost the whole spinal cord. Lumbar puncture (LP) revealed mild pleocytosis and slightly increased protein level. Isoelectric focusing of cerebrospinal fluid (CSF) and serum proteins was normal. Visual evoked potentials were normal. Serological testing excluded acute viral infections. Corticosteroid therapy was applied with good therapeutic response. Control MRI revealed regression of pathological changes in the spinal cord. CONCLUSION: A wide range of disorders can cause LETM, but usually the first line diagnosis is neuromyelitis optica (NMO). Based on the detection of NMO immunoglobulin G in the serum of affected patients, a variety of allied disorders were grouped under the name of NMO spectrum disorders, including recurrent myelitis associated with LETM and myelitis associated with autoimmune disorders such as SS. There have been only a few cases reported in the literature with recurrent LETM associated with non-organ specific autoimmune disorder.

Multislice computed tomography urography in the diagnosis of urinary tract diseases.

BACKGROUND/AIM: . Multislice computed tomography (MSCT) has triggered considerable changes in uroradiological imaging. The aim of this study was to establish the place of MSCT urography (MSCTU) in comparison with intravenous urography (IVU) and to determine the sensitivity and specificity of MSCT in the evaluation of urothelial abnormalities. METHODS: This prospective study included 120 patients with a high clinical suspicion of urinary tract diseases divided into two groups. The group I consisted of 60 patients with macroscopic hematuria, bladder carcinoma and malignant pelvic tumors after radiotherapy or operation. They underwent both IVU and MSCTU. The group II included 60 patients (> or = 40 years old) with retroperitoneal and malignant pelvic tumors, complicated pyelonephritis, microscopic hematuria, acute urinary tract obstruction (without visible calculi on unenhanced scans), and they were submitted to computed tomography with additional scan phase enabling MSCTU. RESULTS: Compared with IVU, MSCTU is more sensitive for the detection of urinary tract diseases (parenchymal changes, renal tumors, urolithiasis, fibrosis) and extraurinary processes. MSCTU is more specific than IVU for renal parenchymal abnormalities, tumors of the excretory system, urolithiasis, bladder tumors, fibrosis and extraurinary diseases. MSCTU is equally sensitive, but more specific for hydronephrosis compared to MSCT. The diagnosis made by the use of MSCTU in patients with macroscopic and microscopic hematuria and with obstruction not caused by stones, perfectly comply with operative findings and histological diagnosis. CONCLUSION: The obtained results support MSCTU to be the modality of choice in the diagnostic algorithm of patients with macroscopic hematuria and in the evaluation of microscopic hematuria and unexplained obstruction of the urinary tract. The only remaining role for IVU in our institution is imaging of the upper urinary tract in patients with hematuria under the age of 40.

Color Doppler ultrasonography and multislice computer tomography angiography in carotid plaque detection and characterization.

BACKGROUND/AIM: Cerebrovascular diseases are the third leading cause of mortality in the world, following malignant and cardiovascular diseases. Therefore, their timely and precise diagnostics is of great importance. The aim of this study was to compare duplex scan Color Doppler ultrasonography (CDU) with multislice computed tomography angiography (MSCTA) in detection of morphological and functional disorders at extracranial level of carotid arteries. METHODS: The study included 75 patients with 150 carotid arteries examined in the period from January 2008 to April 2009. The patients were firstly examined by CDU, then MSCTA, followed by the surgery of extracranial segment of carotid arteries. In 10 patients, the obtained material was referred for histopathological (HP) examination. We used both CDU and MSCT in the analysis of: plaque surface, plaque structure, degree of stenosis, and the presence of in-traplaque hemorrhage. RESULTS: The results obtained by CDU and MSCTA were first compared between themselves, and then to intraoperative findings. Retrospective analysis showed that MSCTA is more sensitive than CDU in assessment of plaque surface (for smooth plaques CDU 89%: MSCTA 97%; for plaques with irregular surface CDU 75% : MSCTA 87%; for ulcerations CDU 54%: MSCTA 87%). Regarding determination of plaque structure (mixed plaque CDU 66% : MSCTA 70%; correlation with HP findings CDU 94% : MSCTA 96%) and localization (CDU 63%: MSCTA 65%), and in terms of sensitivity and specificity, both methods showed almost the same results. Also, there is no statistical difference between these two methods for the degree of stenosis (CDU 96%: MSCTA 98%). CONCLUSION: Atherosclerotic disease of extracranial part of carotid arteries primarily affects population of middle-aged and elderly, showing more associated risk factors. Sensitivity and specificity of CDU and MSCTA regarding plaque composition, the degree of stenosis and plaque localization are almost the same. These results and the fact that there are no adverse effects (high radiation dose) compared to MSCTA indicate that CDU should be the initial method in diagnostic algorythm for carotid arteries.

[Chest computed tomography in the localisation of pathologic processes in lymphomas].

INTRODUCTION: The anatomic localisation of Hodgkin disease and Non-Hodgkin lymphoma is very important in the disease prognosis and therapy treatment. Intrathoracic localisation in Hodgkin disease is very frequent and usually occurs in the form of lymph node enlargement. The most frequent manifestation of the thoracic Non-Hodgkin lymphoma is mediastinal and hilarlympha-denomegalia. The purpose of this research study is to analyse chest computed tomography findings in patients suffering from Hodgkin disease and Non-Hodgkin lymphoma prior to any applied therapy. MATERIAL AND METHODS: This retrospective study encompassed 73 patients diagnosed as having Hodgkin disease or Non-Hodgkin lymphoma. They were subjected to III chest CT examinations. The initial occurrence of the disease was found in 35 patients (24 patients suffering from Hodgkin disease and 11 suffering from Non-Hodgkin lymphoma). Simultaneously, analyses of the pretherapy chest CT findings were made. RESULTS AND DISCUSSION: Positive findings were reported in 66.66% patients suffering from Hodgkin disease and 45.45% patients suffering from Non-Hodgkin lymphoma. Enlarged lymphnodes were found in the region of the upper mediastinum (parathracheal and prevascular group) in more than 55% of the patients suffering from Hodgkin disease and in more than 35% of the patients suffering Non-Hodgkin lymphoma. CONCLUSION: The findings of this study coincide to a great extent with the findings presented in world literature.

[Blunt injuries of the lungs, pleura and chest bone structures: computed tomography contribution].

INTRODUCTION: The most frequent incidences of blunt chest injuries occur due to motorvehicle accidents, falls and work-related traumas. Chest computed tomography is usually associated with examination of the subsequent regions with the aim to enable a more efficient diagnostic procedure. The purpose of this research study is to define the contribution of the chest CT in blunt injury patients. MATERIAL AND METHODS: This retrospective study encompasses the results of CT examination of 36 patients with one or more injuries of the thoracic wall, pleura, lungs and spinal column suspected to suffer chest organs traumas. Chest CT survey was performed in 30 patients, while thoracic spine CT survey was performed in 11 patients. RESULTS AND DISCUSSION: The most frequent incidences of injuries were due to motor vehicle accidents (22 patients--61.11%). Falls were the reason of injuries in 11 patients--17.46%. Chest injuries are usually associated with injuries of the surrounding regions, but occurred in isolated form, too (27.78%). Rib fractures and lungs parenchyma traumas were evidenced by CT examination in more than 60% of the patients. Thoracic spine fractures were most frequently reported at the 10-th, 11-th and 12-th vertebra and made more than 70% of the thoracic spine fractures. CONCLUSION: The findings of this study coincide to a great extent with the findings presented in world literature.

[Current diagnostic trends in radiology].

Since the discovery of X-rays by Wilhelm Conrad Röentgen at the end of the 19th century, diagnostic imaging techniques have been continously improved by technological advances, bringing radiological diagnosis into the very center of modern medicine. Nowadays, it is hard to imagine therapy planning without previous radiological examination. Great advances in the field of computer technology have been accompanied by development of radiological techniques, and today they include not only morphological and anatomical, but also dynamic, functional and molecular imaging. This paper is an overview of new and improved radiological techniques and their implementation.

Renal colic--radiological approach.

Acute flank pain is commonly caused by urolithiasis. This paper discusses advantages and disadvantages of procedures used for evaluation of acute flank pain. In our institution, the diagnostic algorithm includes ultrasonography and plain film radiography, and unenhanced spiral CT in equivocal cases.

[Duplex Doppler ultrasonography in the diagnosis of deep venous thrombosis of the lower extremities].

INTRODUCTION: The aim of this study was to investigate the role of duplex Doppler ultrasonography in diagnosis of deep venous thrombosis (DVT) of the lower extremities. MATERIAL AND METHODS: During a 2-year period, 860 patients were examined by duplex Doppler sonography. Among these, 619 (72%) were women and 241 (28%) men, with the age-range of 16-91; (mean 56,2) years. Siemens Versa Pro colour doppler was used, with 7MHz transducers. Findings were categorized into four categories: 1. deep venous thrombosis (DVT); 2. pathology predominantly related to superficial veins without DVT; 3. pathology of superficial and deep veins; 4. normal findings. RESULTS: 185 (21%) patients had DVT, 366 (42.5%) patients had predominant pathology of superficial veins: postthrombotic syndrome, superficial thrombophlebitis and varicose veins. 128 (14.9%) patients had pathology of superficial and deep veins. Normal findings were found in 181 (21.1%) patients. COCNCLUSIONS: Various vascular and nonvascular diseases may mimic deep venous thrombosis, and that is why US should be used whenever possible to avoid unnecessary anticoagulant therapy.

[Basic characteristics of duplex sonography in the assessment of lower limb arterial circulation].

INTRODUCTION: Dulpex and color duplex ultrasonography of lower limb arteries are valuable non-invasive diagnostic methods in the pathology of vascular diseases and a major step in diagnostics and in follow-up of hemodynamic and morphologic characteristics. COLOR DUPLEX SONOGRAPHY: The method consists of image analysis and analysis of Doppler information. Real-time-B mode is used to visualize the anatomy of blood vessels and other pathological lesions. Doppler information based on the Doppler effect determine the pulse wave i.e. the shape of flow velocity--hemodynamic characteristics. Spectral analysis is the most important element of Doppler examination of the lower limb peripheral arteries. Based on the spectral analysis, there are four stages of lower limb arterial disease: normal findings--1% - 19% diameter reduction; medium stenosis--artery diameter reduction of 20% - 49%; high level stenosis--artery diameter reduction of 50% - 100%; occlusion--no flow detected within the imaged arterial segment. In the first place, both iliac arteries are examined, which is followed with femoral, popliteal and crural arteries. The examination of iliac arteries is carried out with a 3.5 MHz transducer, and other peripheral arteries of the lower limbs are examined with a 7, 5 or 5 MHz transducer. CONCLUSION: Color Doppler is an extremely valuable diagnostic method in detecting pathology of the lower limb arteries. With high reliability level arterial insufficiency and pathological arterial segments are diagnosed by a duplex-Doppler.