Outstanding negative prediction performance of solid pulmonary nodule volume AI for ultra-LDCT baseline lung cancer screening risk stratification

OBJECTIVE

To evaluate performance of AI as a standalone reader in ultra-low-dose CT lung cancer baseline screening, and compare it to that of experienced radiologists.

METHODS

283 participants who underwent a baseline ultra-LDCT scan in Moscow Lung Cancer Screening, between February 2017-2018, and had at least one solid lung nodule, were included. Volumetric nodule measurements were performed by five experienced blinded radiologists, and independently assessed using an AI lung cancer screening prototype (AVIEW LCS, v1.0.34, Coreline Soft, Co. ltd, Seoul, Korea) to automatically detect, measure, and classify solid nodules. Discrepancies were stratified into two groups: positive-misclassification (PM); nodule classified by the reader as a NELSON-plus /EUPS-indeterminate/positive nodule, which at the reference consensus read was < 100 mm3, and negative-misclassification (NM); nodule classified as a NELSON-plus /EUPS-negative nodule, which at consensus read was ≥ 100 mm3.

RESULTS

1149 nodules with a solid-component were detected, of which 878 were classified as solid nodules. For the largest solid nodule per participant (n = 283); 61 [21.6 %; 53 PM, 8 NM] discrepancies were reported for AI as a standalone reader, compared to 43 [15.1 %; 22 PM, 21 NM], 36 [12.7 %; 25 PM, 11 NM], 29 [10.2 %; 25 PM, 4 NM], 28 [9.9 %; 6 PM, 22 NM], and 50 [17.7 %; 15 PM, 35 NM] discrepancies for readers 1, 2, 3, 4, and 5 respectively.

CONCLUSION

Our results suggest that through the use of AI as an impartial reader in baseline lung cancer screening, negative-misclassification results could exceed that of four out of five experienced radiologists, and radiologists' workload could be drastically diminished by up to 86.7%.

Braincase anatomy of extant Crocodylia, with new insights into the development and evolution of the neurocranium in crocodylomorphs

Present-day crocodylians exhibit a remarkably akinetic skull with a highly modified braincase. We present a comprehensive description of the neurocranial osteology of extant crocodylians, with notes on the development of individual skeletal elements and a discussion of the terminology used for this project. The quadrate is rigidly fixed by multiple contacts with most braincase elements. The parabasisphenoid is sutured to the pterygoids (palate) and the quadrate (suspensorium); as a result, the basipterygoid joint is completely immobilized. The prootic is reduced and externally concealed by the quadrate. It has a verticalized buttress that participates in the canal for the temporal vasculature. The ventrolateral processes of the otoccipitals completely cover the posteroventral region of the braincase, enclose the occipital nerves and blood vessels in narrow bony canals and also provide additional sutural contacts between the braincase elements and further consolidate the posterior portion of the crocodylian skull. The otic capsule of crocodylians has a characteristic cochlear prominence that corresponds to the lateral route of the perilymphatic sac. Complex internal structures of the otoccipital (extracapsular buttress) additionally arrange the neurovascular structures of the periotic space of the cranium. Most of the braincase elements of crocodylians are excavated by the paratympanic pneumatic sinuses. The braincase in various extant crocodylians has an overall similar structure with some consistent variation between taxa. Several newly observed features of the braincase are present in Gavialis gangeticus and extant members of Crocodylidae to the exclusion of alligatorids: the reduced exposure of the prootic buttress on the floor of the temporal canal, the sagittal nuchal crest of the supraoccipital projecting posteriorly beyond the postoccipital processes and the reduced paratympanic pneumaticity. The most distinctive features of the crocodylian braincase (fixed quadrate and basipterygoid joint, consolidated occiput) evolved relatively rapidly at the base of Crocodylomorpha and accompanied the initial diversification of this clade during the Late Triassic and Early Jurassic. We hypothesize that profound rearrangements in the individual development of the braincases of basal crocodylomorphs underlie these rapid evolutionary modifications. These rearrangements are likely reflected in the embryonic development of extant crocodylians and include the involvement of neomorphic dermal anlagen in different portions of the developing chondrocranium, the extensive ossification of the palatoquadrate cartilage as a single expanded quadrate and the anteromedial inclination of the quadrate.

A simplified cluster model and a tool adapted for collaborative labeling of lung cancer CT scans

BACKGROUND AND OBJECTIVE

Lung cancer is the most common type of cancer with a high mortality rate. Early detection using medical imaging is critically important for the long-term survival of the patients. Computer-aided diagnosis (CAD) tools can potentially reduce the number of incorrect interpretations of medical image data by radiologists. Datasets with adequate sample size, annotation, and truth are the dominant factors in developing and training effective CAD algorithms. The objective of this study was to produce a practical approach and a tool for the creation of medical image datasets.

METHODS

The proposed model uses the modified maximum transverse diameter approach to mark a putative lung nodule. The modification involves the possibility to use a set of overlapping spheres of appropriate size to approximate the shape of the nodule. The algorithm embedded in the model also groups the marks made by different readers for the same lesion. We used the data of 536 randomly selected patients of Moscow outpatient clinics to create a dataset of standard-dose chest computed tomography (CT) scans utilizing the double-reading approach with arbitration. Six volunteer radiologists independently produced a report for each scan using the proposed model with the main focus on the detection of lesions with sizes ranging from 3 to 30 mm. After this, an arbitrator reviewed their marks and annotations.

RESULTS

The maximum transverse diameter approach outperformed the alternative methods (3D box, ellipsoid, and complete outline construction) in a study of 10,000 computer-generated tumor models of different shapes in terms of accuracy and speed of nodule shape approximation. The markup and annotation of the CTLungCa-500 dataset revealed 72 studies containing no lung nodules. The remaining 464 CT scans contained 3151 lesions marked by at least one radiologist: 56%, 14%, and 29% of the lesions were malignant, benign, and non-nodular, respectively. 2887 lesions have the target size of 3-30 mm. Only 70 nodules were uniformly identified by all the six readers. An increase in the number of independent readers providing CT scans interpretations led to an accuracy increase associated with a decrease in agreement. The dataset markup process took three working weeks.

CONCLUSIONS

The developed cluster model simplifies the collaborative and crowdsourced creation of image repositories and makes it time-efficient. Our proof-of-concept dataset provides a valuable source of annotated medical imaging data for training CAD algorithms aimed at early detection of lung nodules. The tool and the dataset are publicly available at https://github.com/Center-of-Diagnostics-and-Telemedicine/FAnTom.git and https://mosmed.ai/en/datasets/ct_lungcancer_500/, respectively.

[Adrenal imaging: anatomy and pathology (literature review)]

This literature review focuses on the normal adrenal gland anatomy and typical imaging features necessary to evaluate benign and malignant lesions. In particular, adenoma, pheochromocytoma, metastases and adrenocortical carcinoma were discussed as some of the most common lesions. For this purpose, a review of relevant local and international literature sources up to January 2021 was conducted.In many cases, adrenal incidentalomas have distinctive features allowing characterization using noninvasive methods. It is possible to suspect a malignant nature and promptly refer the patient for the necessary invasive examinations in some cases. -Computed tomography, especially with intravenous contrast enhancement, is the primary imaging modality because it enables differential diagnosis. Magnetic resonance tomography remains a sensitive method in lesion detection and follow-up but is not very specific for determining the malignant potential. Positron emission computed tomography also remains an additional method and is used mainly for differential diagnosis of malignant tumors, detecting metastases and recurrences after surgical treatment. Ultrasound has a limited role but is nevertheless of great importance in the pediatric population, especially newborns. Promising techniques such as radiomics and dual-energy CT can expand imaging capabilities and improve diagnostic accuracy.Because adrenal lesions are often incidentally detected by imaging performed for other reasons, it is vital to interpret such findings correctly. This review should give the reader a broad overview of how different imaging modalities can evaluate adrenal pathology and guide radiologists and clinicians.

Chest MRI of patients with COVID-19

During the pandemic of novel coronavirus infection (COVID-19), computed tomography (CT) showed its effectiveness in diagnosis of coronavirus infection. However, ionizing radiation during CT studies causes concern for patients who require dynamic observation, as well as for examination of children and young people. For this retrospective study, we included 15 suspected for COVID-19 patients who were hospitalized in April 2020, Russia. There were 4 adults with positive polymerase chain reaction (PCR) test for COVID-19. All patients underwent magnetic resonance imaging (MRI) examinations using MR-LUND PROTOCOL: Single-shot Fast Spin Echo (SSFSE), LAVA 3D and IDEAL 3D, Echo-planar imaging (EPI) diffusion-weighted imaging (DWI) and Fast Spin Echo (FSE) T2 weighted imaging (T2WI). On T2WI changes were identified in 9 (60,0%) patients, on DWI - in 5 (33,3%) patients. In 5 (33,3%) patients lesions of the parenchyma were visualized on T2WI and DWI simultaneously. At the same time, 4 (26.7%) patients had changes in lung tissue only on T2WI. (P(McNemar) = 0,125; OR = 0,00 (95%); kappa = 0,500). In those patients who had CT scan, the changes were comparable to MRI. The results showed that in case of CT is not available, it is advisable to conduct a chest MRI for patients with suspected or confirmed COVID-19. Considering that T2WI is a fluid-sensitive sequence, if imaging for the lung infiltration is required, we can recommend the abbreviated MRI protocol consisting of T2 and T1 WI. These data may be applicable for interpreting other studies, such as thoracic spine MRI, detecting signs of viral pneumonia of asymptomatic patients. MRI can detect features of viral pneumonia.

Methodology and tools for creating training samples for artificial intelligence systems for recognizing lung cancer on CT images

Introduction. Medical imaging techniques can diagnose many diseases at the early stages of their development, improving the patient survival. Artificial intelligence (AI) systems, requiring the high-quality annotated and marked-up sets of medical images, are a suitable and promising means of improving the diagnostics’ quality. The purpose of the study was to develop a methodology and software for creating AIS training sets. Material and methods. We compared the main annotation methods’ performance and accuracy and based the information system on the most efficient method in both domains to develop an optimal approach. To markup objects of interest, we used the cluster model of lesions localization previously developed by the authors. We used C++ and Kotlin programming languages for software development. Results. A structured annotation template with delivered a glossary of terms became the basis of the information system. The latter consists of three interacting modules, two of which are executed on a remote server’s capacities and one on a personal computer or mobile device of the end-user. The first module is a web service responsible for the workflow logic. The second module, a web server, is responsible for interacting with client applications. Its role is to identify users and manage the database and Picture Archiving and Communication System (PACS) connections. The front-end module is a web application with a graphical interface that assists the end-user in images’ markup and annotation. Conclusions. An algorithmic basis and a software package have been created for annotation and markup of CT images. The resulting information system was used in a large-scale lung cancer screening project for the creation of medical imaging datasets.

[Artificial intelligence for diagnosis of vertebral compression fractures using a morphometric analysis model, based on convolutional neural networks]

BACKGROUND

Pathological low-energy (LE) vertebral compression fractures (VFs) are common complications of osteoporosis and predictors of subsequent LE fractures. In 84% of cases, VFs are not reported on chest CT (CCT), which calls for the development of an artificial intelligence-based (AI) assistant that would help radiology specialists to improve the diagnosis of osteoporosis complications and prevent new LE fractures.

AIMS

To develop an AI model for automated diagnosis of compression fractures of the thoracic spine based on chest CT images.

MATERIALS AND METHODS

Between September 2019 and May 2020 the authors performed a retrospective sampling study of ССТ images. The 160 of results were selected and anonymized. The data was labeled by seven readers. Using the morphometric analysis, the investigators received the following metric data: ventral, medial and dorsal dimensions. This was followed by a semiquantitative assessment of VFs degree. The data was used to develop the Comprise-G AI mode based on CNN, which subsequently measured the size of the vertebral bodies and then calculates the compression degree. The model was evaluated with the ROC curve analysis and by calculating sensitivity and specificity values.

RESULTS

Formed data consist of 160 patients (a training group - 100 patients; a test group - 60 patients). The total of 2,066 vertebrae was annotated. When detecting Grade 2 and 3 maximum VFs in patients the Comprise-G model demonstrated sensitivity - 90,7%, specificity - 90,7%, AUC ROC - 0.974 on the 5-FOLD cross-validation data of the training dataset; on the test data - sensitivity - 83,2%, specificity - 90,0%, AUC ROC - 0.956; in vertebrae demonstrated sensitivity - 91,5%, specificity - 95,2%, AUC ROC - 0.981 on the cross-validation data; for the test data sensitivity - 79,3%, specificity - 98,7%, AUC ROC - 0.978.

CONCLUSIONS

The Comprise-G model demonstrated high diagnostic capabilities in detecting the VFs on CCT images and can be recommended for further validation.

[Epicardial fat Tissue Volumetry: Comparison of Semi-Automatic Measurement and the Machine Learning Algorithm]

Aim        To compare assessments of epicardial adipose tissue (EAT) volumes obtained with a semi-automatic, physician-performed analysis and an automatic analysis using a machine-learning algorithm by data of low-dose (LDCT) and standard computed tomography (CT) of chest organs.Material and methods        This analytical, retrospective, transversal study randomly included 100 patients from a database of a united radiological informational service (URIS). The patients underwent LDCT as a part of the project "Low-dose chest computed tomography as a screening method for detection of lung cancer and other diseases of chest organs" (n=50) and chest CT according to a standard protocol (n=50) in outpatient clinics of Moscow. Each image was read by two radiologists on a Syngo. via VB20 workstation. In addition, each image was evaluated with a developed machine-learning algorithm, which provides a completely automatic measurement of EAT.Results   Comparison of EAT volumes obtained with chest LDCT and CT showed highly consistent results both for the expert-performed semi-automatic analyses (correlation coefficient &gt;98 %) and between the expert layout and the machine-learning algorithm (correlation coefficient &gt;95 %). Time of performing segmentation and volumetry on one image with the machine-learning algorithm was not longer than 40 sec, which was 30 times faster than the quantitative analysis performed by an expert and potentially facilitated quantification of the EAT volume in the clinical conditions.Conclusion            The proposed method of automatic volumetry will expedite the analysis of EAT for predicting the risk of ischemic heart disease.

[Moscow screening: breast cancer screening with mammography as a method of improving early stage cancer detection]

A list of organizational, management, and clinical steps that are crucial for creating an effective breast cancer screening program as part of the state medical benefits scheme in Moscow is presented. We identified key performance indicators for each stage of the screening program. Performance of radiologists and radiology technicians was evaluated, including assessing the accuracy of both single and double reading of mammograms. We streamlined an efficient system for patient routing between the stages of the screening program and developed methodological materials for patients and medical specialists. A shortened structured protocol for mammography interpretation, including second reading, was created in compliance with terms of Moscow Compulsory Medical Insurance Fund. We conceived a framework of educational activities to assess and improve skills and knowledge of radiologists and other specialists participating in the screening.

[Moscow Screening: Lung Cancer Screening With Low-Dose Computed Tomography]

For the first time in Moscow and Russia, a program of selective lung cancer screening has been implemented with a comprehensive approach, including organizational, management, medical, technical and educational aspects and quality control. Unique ultra-low-dose protocols (ultra-LDCT) have been developed to implement the screening program. These protocols allow performing high-quality chest computed tomography for lung nodule detection with an effective dose of less than 1 mSv. The possibility of using neural networks ("artificial intelligence") for quality control of screening results has been proven for the first time.

[The future of computer-aided diagnostics in chest computed tomography]

Recently, more and more attention has been paid to the utility of artificial intelligence in medicine. Radiology differs from other medical specialties with its high digitalization, so most software developers operationalize this area of medicine. The primary condition for machine learning is met because medical diagnostic images have high reproducibility. Today, the most common anatomic area for computed tomography is the thorax, particularly with the widespread lung cancer screening programs using low-dose computed tomography. In this regard, the amount of information that needs to be processed by a radiologist is snowballing. Thus, automatic image analysis will allow more studies to be interpreted. This review is aimed at highlighting the possibilities of machine learning in the chest computed tomography.

Age and Gender Differences of the Frontal Bone: A Computed Tomographic (CT)-Based Study

BACKGROUND

Age-related changes of the frontal bone in both males and females have received limited attention, although understanding these changes is crucial to developing the best surgical and nonsurgical treatment plans for this area.

OBJECTIVES

To investigate age-related and gender-related changes of the forehead.

METHODS

Cranial computed tomographic images from 157 Caucasian individuals were investigated (10 males and 10 females from each of the following decades: 20-29 years, 30-39 years, 40-49 years, 50-59 years, 60-69 years, 70-79 years, 80-89 years, and of 8 males and 9 females aged 90-98 years). Frontal bone thickness and forehead distance measurements were carried out to analyze age and gender differences.

RESULTS

With increasing age, the size of a male forehead reduces until no significant differences to a female forehead is present at old age (P = 0.307). The thickness of the frontal bone of the lower forehead (≤4 cm cranial to the nasal root) increased slightly in both genders with increasing age. In the upper forehead (≥4 cm cranial to the nasal root), frontal bone thickness decreased significantly (P = 0.002) in males but showed no statistically significant change in thickness in females (P = 0.165).

CONCLUSIONS

The shape of the frontal bone varies in young individuals of different genders and undergoes complex changes with age because of bone remodeling. Understanding these bony changes, in addition to those in the soft tissues, helps physicians choose the best surgical and nonsurgical treatment options for the forehead.

LEVEL OF EVIDENCE: 4

[Application of a modified Time-SLIP MRI sequence for visualization of cerebrospinal fluid movement in the cerebral aqueduct and cervical spinal canal]

Direct visualization of rapid cerebrospinal fluid movements is a topical task of neurosurgery, which has applications such as evaluating hydrocephalus and the effectiveness of 3rd ventriculostomy.

PURPOSE

The study purpose was to evaluate the capabilities of a modified Time-SLIP pulse MRI sequence for visualization of fluid (CSF) movements in the phantom, healthy subject, and patient.

MATERIAL AND METHODS

The study was performed in a phantom simulating pulsed CSF movements, healthy volunteers (9 people), and patients without impaired CSF dynamics (12 people), whose data were used to determine mean CSF flow parameters, as well as in 1 patient after 3rd ventriculostomy. A 1.5 T MRI instrument was used. The Time-SLIP parameters were as follows: TR = 8,500 ms; TEeff = 80 ms; Thk = 5.0 mm; tag spacing = 30 mm; NEX 7; inversion time (BBTI) = 2,000/3,000 ms; no cardiosynchronization. Scanning time was 2:16 min. The estimated parameter was the length of motion (LOM) of CSF.

RESULTS

According to a study on a phantom simulating various conditions of oscillatory fluid motion, the mean LOM determination error in the modified Time-SLIP mode was 20%. This technique provided the following LOM data for the cerebral aqueduct (median, 25-75% quartiles): 13.0 (9.5-16.0) mm for BBTI of 2,000ms and 30.2 (23.7-35.3) mm for BBTI of 3,000 ms, i.e. 2.3-fold higher. This difference may be explained by an intense turbulent current leading to rapid CSF exchange between the 3rd and 4th ventricles and prolonged CSF movement during several heart contractions. Quantitative parameters of CSF movement at the C1-C2 level were determined. Additionally, Time-SLIP was used to evaluate performance of a third ventricle fistula.

CONCLUSION

We have proposed a modified Time-SLIP pulse sequence that does not require cardiosynchronization. The mean relative error in determining the CSF movement distance was 20%. The mean quantitative parameters of CSF movement in the cerebral aqueduct and at the C1-C2 level were obtained. Turbulent CSF flow is found in the cerebral aqueduct, which leads to rapid exchange between the 3rd and 4th ventricles.

Calvarial Volume Loss and Facial Aging: A Computed Tomographic (CT)-Based Study

BACKGROUND

Our understanding of the aging changes involving the cranium and its impact on the overlying soft tissues is limited.

OBJECTIVES

This study was designed to look at the changes that occur in the cranium with aging and to propose an additional mechanism for loss of support for overlying soft tissues.

METHODS

One hundred and fifty-seven white individuals (10 males and 10 females in each decade: 20-29 years, 30-39 years, 40-49 years, 50-59 years, 60-69 years, 70-79 years, 80-89 years, and 8 males and 9 females aged 90-98 years) were investigated. Computed tomographic (CT) multiplanar scans with standardized measurements of cranial thickness were performed for the frontal bone, nasion, vertex, pterion, lambda, calvarial and midfacial height, and sagittal and transverse diameter.

RESULTS

Increasing age correlated with a decrease in sagittal diameter in both males (rp = -0.201) and females (rp = -0.055) but with an increase in transverse diameter in both males (rp = 0.233) and females (rp = 0.207). Frontal bone thickness decreased in males -1.57mm/-18.14%, whereas it increased slightly in females +0.26mm/+3.04%. At the pterion, bone thickness increased significantly in both genders. Calvarial volume decreased with increased age in both males and females: -70.2 ml/-5.35% and -61.4 ml/-5.10%, respectively.

CONCLUSIONS

The lateral expansion of the skull may favor a skeletonized appearance of the face in elderly individuals. The computed volume of the calvaria decreased with advancing age in both genders, providing an additional element in the multifactorial model for facial soft-tissue laxity.

LEVEL OF EVIDENCE 2

[Professional standards and unsolved issues of vocational training of radiologists]

This article describes the main statements of the Professional standards of radiologists, statements regarding vocational radiologists training, included in the Orders of the Ministry of Health of the Russian Federation and the educational standards in the specialty "Radiology', approved by the Ministry of Education and Science of the Russian Federation.

[Magnetic resonance spectroscopy of the prostate: a description of the methodology and the own results]

The first part of the article discusses the technical details of the magnetic resonance spectroscopy (MRS) of the prostate, postprocessing and assessment of the results; the second part of article presents a several own clinical examples, and describes the advantages and disadvantages of the methodology. Of all available clinical MRI techniques for the evaluation of the prostate multivoxel spectroscopy is the most difficult. Thus, even with abidance of all the technical aspects of the evaluation, it impossible to be sure absolutely that qualitative range of voxels of interest will be received. Upon receipt of quality results with interpretable spectra, it is still difficult to perform the differential diagnosis of cancer with benign changes. These complexities limit the widespread use of prostate MRS. In our opinion, the use of this method is most effective for a diagnosis of cancer localized in the peripheral zone of the prostate, and for the assessment of the dynamics of non-surgical treatment of the tumor.

[Errors when performing computed tomographic colonography (virtual colonoscopy) and assessing its results]

Computed tomographic colonography (CTC) is a noninvasive diagnostic method for significantly identifying clinically relevant colonic and rectal tumors. Good colonic preparation that includes laxatives or residue-free diet, as well as labelling the intestinal contents is needed to adequately interpret CTC data. However, errors in interpreting the results of CTC can be associated with not only the imperfections of large bowel preparation for examination, but also due to those of the latter and because of the anatomic features of the colon. The paper describes difficulties and the most common errors in CTC, including own experience.

[Opportunities of computed tomographic colonography in detecting of colon neoplasms]

The computed tomographic colonoscopy (CTC) was performed in 212 patients on the multislice computed tomography Siemens Open in low-dose mode during the period from 2010 to 2013. CTC was tolerated well by 80% of patients. 20% of patients complained of mild discomfort during the study. The optical colonoscopy with biopsy was done in 53 (25%) of 212 patients after CPC. This is due to the fact that it was not detected the significant endoluminal structures in other observations or small polyps were found in elderly patients. In these cases the risk of colonoscopy was not justified. Sensitivity and specificity of CTC was 55 and 91% respectively for the detection of polyps with diameter less than 5 mm; for polyps 5-9 mm - 85 and 93%; for polyps with diameter greater than 10 mm - 100 and 92%.

[Diagnostics of the primary multiple forms of the colorectal cancer]

The issue analyses the diagnostics of the repeated malignant lesions of the colorectal region. The study covers the two decades period (1992-2011 yy). Of the observed patients with primary colorectal tumors, 238 showed the repeated lesions of the region. The article focuses on the on-time diagnostics and differential approach to the repeated malignancies of the colorectal region.

[Multislice spiral computed tomography of coronary arteries: procedure development stages and clinical application]

The paper analyzes the data available in the literature on the possibility of using multislice spiral computed tomography in patients with acute coronary syndrome. The authors give the results of their study of the diagnostic value of 64-slice computed tomography in patients with presumptive coronary heart disease (CHD) and its high risk according to the Framingham risk scale (Group 1) versus those with its already established diagnosis (Group 2). The sensitivity of 64-slice computed tomography was 97.8 and 90.2 in Groups 1 and 2, respectively; its specificity was 98.6 and 78.2% in these groups.

[The use of multi-spiral computer tomography for early diagnosis of coronary artery stenoses in patients with high risk of development ischemic heart disease]

Results of the study of clinico-diagnostic value of multispiral computed tomography in patients with suspected ischemic heart disease (IHD) are described in this paper. We have used 64-slice spiral computer tomography in examination of 49 patients with high IHD risk referred to the cardiological hospital for IHD exclusion. We have demonstrated high capacity of this method in diagnosis of early stages of atherosclerotic coronary artery involvement. This will allow timely detection of such patients and to intervene on modifiable IHD risk factors with the aim of lowering risk of development of unfavorable clinical manifestations of IHD, such as acute coronary syndrome and sudden death.

[Diagnosis and effective surgical treatment of constrictive pericarditis]

Constrictive pericarditis is a rare and severe disease. Timely and correct differential diagnosis of this pathology facilitates choice of necessary tactics of treatment and thus improve prognosis and quality of life. In this paper we present clinical case report of a patient with constrictive pericarditis. The disease was diagnosed on the basis of clinical picture, data of X-ray and echocardiographic investigation, and confirmed by multispiral computed tomography (MSCT). The patient was subjected to pericardioectomy with positive clinical effect and results of repeated echocardiography and MSCT.

[Multiple myeloma: innovations in diagnosis]

Multiple myeloma (MM) belongs to the group of paraproteinemic hemoblastosis. Its clinical picture varies but the main clinical presentation is bone tumor proliferation resultant from enhanced resorption of tumor tissue related to bone marrow infiltration with plasmic cells, activation of osteoclasts. This leads to marked ossalgic syndrome and pathological bone fragility. MM often runs with nephropathy, immunodepression, hemopoietic disorders. Non-specific clinical manifestations of MM cause difficulties in making accurate diagnosis. Our clinic introduces innovative high-tech methods of examination including MR tomography of the body which detects the disease at early stages and, finally, allows us to prolong the patient's life.

[Multiple myeloma: evaluation of invasiveness by magnetic resonance imaging]

The paper presents a case history of multiple myeloma in a female patient. Its diagnosis was established only 10 years after the onset of the disease, which results in severe invalidity (she was treated with calcium preparations in accordance with the diagnosis of generalized osteoporosis. Persistent therapy with calcium preparations was ineffective; the number of pathological fractures increased. Further bone study and current instrumental imaging methods could make a precise diagnosis and use etiotropic treatment, which yielded a positive clinical effect. The data on high-technology studies, body magnetic resonance imaging used in the diagnosis of the diseases accompanied by bone destructive changes are given. The problems in the diagnosis of multiple myeloma are outlined.

[Diagnosis of malignant pericardial mesothelioma]

Continuing growth of rate of detection of primary tumors of the heart has been noted recently. Prevalence of cardiac tumors in European population according to data of different authors varies from 25 to 5500 cases per 1 million of autopsies. Malignant mesothelioma belongs to most rarely met tumors. In most cases pericardial malignant mesothelioma possesses high secretory capacity what allows to suspect tumorous process in hemorrhagic pericarditis with recurrences after repetitive punctures. The paper contains description of a patient with malignant pericardial mesothelioma. Special feature of this case has been atypical clinical course of the disease complicated by development of acute myocardial infarction of posterior left ventricular wall.

[Clinical aspects of diagnostics and surgical treatment of acute primary purulent destructive pyelonephritis]

79 patients with the acute primary non-obstructive pyelonephritis were treated during 2003-2006. 24 (30.3%) patients were operated on with the diagnosis of acute primary purulent destructive pyelonephritis. Organopreserving operations were performed in 23 (95.8%) of patients. The early diagnostics of purulent destructive complications of pyelonephritis, using the developed diagnostic algorithm, and modified operative technique allowed to increase the rate of organopreserving operations, avoid reinterventions and decrease the risk of intraoperative complications.

[Study of the capacities of magnetic resonance imaging in the diagnosis of knee joint injuries]

Joint injury is presently one of the main causes of temporary disability of an economically and socially active population. The precise preoperative diagnosis enables the planning of adequate surgical intervention, reduction of the time of disability, and improvement of quality of life. However, magnetic resonance imaging (MRI) most commonly performed in patients with knee joint injury shows a high variability in diagnostic efficiency. Based on a multicenter study, the paper analyzes main reasons for diagnostic errors in knee joint MRI and gives recommendations on how to use of this technique.

[The degree of coronary artery calcinosis as a prognostic factor of asymptomatic cardiovascular complications: results of meta-analysis]

AIM

To investigate prognostic implications of the calcium index estimated tomographycally for identification of patients at high risk to develop cardiovascular complications (non-fatal myocardial infarction, lethal coronary hear disease, coronary revascularization) in the absence of clinical manifestations.

MATERIAL AND METHODS

Meta-analysis of the results of studies on prognostic implications of coronary arteries calcinosis was made with standardized risk ratio as a metameter. The meta-analysis included tests for systemic error related to publishing primarily positive results and data heterogenicity.

RESULTS

Overall risk ratios for cardiovascular complications ranged from 2.1 to 9.3 for different degrees of coronary artery calcinosis.

CONCLUSION

Calcium index is an independent risk factor of complications of cardiovascular diseases.

Localization of the motor and speech zones of the cerebral cortex by functional magnetic resonance tomography

Functional magnetic resonance tomography provides a non-invasive method for mapping the cerebral cortex. The aim of the present work was to assess the potential and suitability of this method in a series of brain disorders. Studies were performed on 32 volunteers (mean age 37.8 +/- 20.9 years) and 16 patients with tumors of the cerebral cortex (mean age 36.2 +/- 24.2 years). Initial functional images were processed by statistical methods. Computed activation maps were superimposed on anatomical images. In 89% of cases, functional magnetic resonance tomography allowed the motor cortex and Broca's area to be localized; in almost 69%, the method impinged on the therapeutic tactics used in patients with cerebral cortex lesions. Thus, functional magnetic resonance tomography can be used in clinical conditions to obtain information not yielded by other diagnostic methods and which can be used to plan the neurosurgical treatment of patients with supratentorial brain tumors with maximum preservation of cerebral cortex function. Assessments of the state of the motor and speech areas by this tomographic method has potential applications in neurosurgery and neurophysiology.

[Localization of motor and speech cortex in the brain with functional magnetic resonance tomography]

Functional magnetic resonance imaging (MRI) can be used for non-invasive mapping of cerebral cortex. The purpose of the study was evaluation of applicability of functional MRI for studies of neurosurgical patients. 32 volunteers (mean age 37.8 +/- 20.9 years) and 16 patients with brain tumors (mean age 36.2 +/- 24.2 years) were included in the study. Statistical analysis of the data obtained was performed. Activation maps were superimposed on anatomical images and discussed with neurosurgeons. Functional MRI studies were successful in localising the motor cortex and Broca's area in 89% of cases. In 69% of cases, results of the functional MRI influenced the patients' treatment.