Contrast Agents Based on Iron Oxide Nanoparticles for Clinical Magnetic Resonance Imaging.

Magnetic resonance imaging (MRI) is one of the most perspective methods of noninvasive visualization in medicine, and use of contrast agents significantly its potentialities extends. Iron oxide nanoparticles are promising contrast agents, but in fact all the data on their efficiency were obtained in high-field tomographs for experimental animals. We studied the possibility of using magnetic nanoparticles for MRI visualization of rat brain glioblastoma at the most common clinical field 1.5 T The data indicate the efficiency of iron oxide magnetic nanoparticles as contrast agents for 1.5 T MR tomographs.

[State of the art of the problem concerning endovascular treatment of abdominal aortic aneurysms of infrarenal localization]. / Sovremennoe sostoianie problemy éndovaskuliarnogo lecheniia anevrizm briushnoi aorty infrarenal'noi lokalizatsii.

The problem concerning diagnosis and treatment of abdominal aortic aneurysms (AAA) is important today because of a high proportion of this pathology within the structure of population morbidity and mortality, with a tendency of these indices to increase, as well as high lethality rates in development of complications. Endovascular treatment of aortic aneurysms is one of the most rapidly developing methods of treatment in vascular surgery. Over the last two decades this type of treatment has been playing an important part in the armamentarium of the vascular surgeon and is often considered as primary treatment of patients with AAA of infrarenal localization. Nevertheless, long-term efficacy and reliability of this method have been argued. These argues are based on the fact that according to the findings of various studies the advantages of endovascular treatment of aneurysms over open surgical treatment are completely leveled after 6-8 years. The main disadvantage of endovascular treatment is the necessity of repeat interventions in the long-term period of follow-up. However, in a series of studies repeat interventions in groups of both surgical and endovascular treatment were either not taken into account or not specially studied. It should also be taken into consideration that first European studies were carried out with the use of grafts of first generations, and some of them are not used any more. Therefore, the necessity of carrying out further studies still remains. Perhaps, new generations will be able to decrease the frequency of repeat interventions and thereby improve the overall results of endovascular treatment. The possibilities of endovascular treatment of AAAs will constantly be extended, including due to the development of X-ray equipment and software, as well as at the expense of various auxiliary technologies.

[Magnetic resonance imaging in the diagnosis of recurrent prostate cancer].

The article reviews the domestic and international literature on local recurrence of prostate cancer both after surgery and non-invasive treatments. The authors describe modern high-precision techniques used in magnetic resonance imaging that are used today in clinical practice for the most accurate detection of recurrent prostate cancer lesions.

[The persistent trigeminal artery as evidenced by multislice spiral computed tomographic angiography].

OBJECTIVE: To determine the incidence of the persistent trigeminal artery (PTA) and to reveal its relationship to cerebral aneurysms, as well as the concomitant anatomic features of cerebral arteries according to the data of multislice spiral computed tomographic angiography (CTA). MATERIAL AND METHODS. A total of 1041 patients underwent brachiocephalic artery CTA according to different clinical indications. PTA and cerebral arterial aneurysms were found on the computed tomographic angiograms and the anatomic features of the structure of the circle of Willis were assessed. RESULTS: PTA was identified in 6 (0.58%) of the 1041 patients. Cerebral aneurysm was present in only one patient with PTA and concurrent with hypoplasia of the contralateral A1 segment of the anterior cerebral artery. Hypoplasia of the basilar artery (BA) and both vertebral arteries (VA) was observed in 3 (60%) cases, with the diameter of PTA at its confluence with BA exceeding 3 mm. When the diameter of BA was normal, that of PTA was less than 2 mm. All PTAs were wider at their base, by decreasing in diameters distally. CONCLUSION: CTA showed that the incidence of PTA was 0.58% and its lateral type according to the Salas classification and Saltzman's type 1 were more common (5/6). In 4 cases, PTA was concurrent with VA and BA hypoplasia, with its degree being inversely related to the distal diameter of PTA. There was no convincing evidence for a relationship of PTA to cerebral aneurysms.

[Atrial fibrillation as consequence and cause of structural changes of atria].

Changes of atrial structure and function are the contributors of atrial fibrillation clinical course, complications and treatment effectiveness. Effects of inflammation and mechanical stretch on atrial structural remodeling leading to atrial fibrillation are reviewed in the article. Contemporary invasive and non-invasive methods of evaluation (including late gadolinium enhancement magnetic resonance imaging) of patients with atrial structural remodeling in atrial fibrillation are also described.

[Informative value of multislice spiral computed tomography in identifying myocardial perfusion defect in patients with acute myocardial infarction].

AIM: To estimate the informative value of multislice spiral computed tomography (MSCT) in the diagnosis of myocardial infarction (MI). SUBJECTS AND METHODS: The study enrolled 171 patients with acute coronary syndrome (ACS), including 121 patients diagnosed with acute ST-segment elevation MI (STEMI), 19 with non-STEMI, and 31 with unstable angina. A comparison group consisted of 52 patients with stable coronary heart disease (CHD) and a control group comprised 17 patients without CHD. Intravenous contrast-enhanced MSCT was performed using a 64-spiral CT scanner. MSCT was carried out in the patients with ACS on days 3-5 of the onset of a pain attack and in the other patients electively. It was redone in 44 patients with acute MI (AMI) 6 months after a primary examination. RESULTS: Left ventricular (LV) perfusion defect was imaged in 94.3% of the patients with AMI and in 10% of those with unstable angina. LV contrast defects were undetectable in the patients from the stable CHD and control groups. The sensitivity, specificity, prognostic value of a positive result, negative prognostic value of a result, and accuracy of MSCT in the diagnosis of MI were 94.3, 97.1, 97.8, 92.5, and 96.70%, respectively. In the patients with STEMI, myocardial perfusion defect was larger and transmural perfusion defect was more common than in those with non-STEMI. Comparison of the values of myocardial perfusion defect size and myocardial density according to the data of primary and repeat MSCT revealed no statistically significant differences: 2.0 (0.50; 5.45) and 1,8 (0.35; 5.00) cm3 (p = 0.15); 41.7 +/- 10.2 and 46.1 +/- 12.2 HU, respectively (p = 0.07). CONCLUSION: Contrast-enhanced MSCT allows visual and quantitative assessments of myocardial perfusion defect in patients with ACS. Myocardial perfusion defect from MSCT data suggests previous MI with a high probability, but does not permit the determination of the duration of the disease.

[Comprehensive magnetic resonance imaging for breast cancer].

AIM: To enhance the efficiency of diagnosis of breast tumors by comprehensive magnetic resonance imaging (MRI) involving dynamic contrast-enhanced magnetic resonance mammography (MRM) and magnetic resonance spectroscopy (MRS). SUBJECTS AND METHODS: Eighty-seven women aged 32 to 75 years with breast neoplasms were examined. MRM was performed on a Philips Achieva 3.0T TX scanner. The MRI protocol consisted of axial fat-suppressed T1- and T2-weighted spin-echo images and 8 postcontrast dynamic series. Changes in contrast-enhanced MRI of breast cancer (BC) were estimated by constructing the signal intensity-time curves. MRS was carried out using a PRESS sequence. RESULTS: Dynamic MRM determined type III signal intensity-time curve in 83.9% of the patients with BC and type II curve in 16.1% of those with breast malignancies and in 33.3% of those with breast fibroadenomas. Type I signal intensity-time curve was identified in 66.7% of the cases of fibroadenomas. Elevated choline concentrations in the malignancies were detected in 17.7% of cases. Their tumors were larger than 2 cm. The choline peak in the malignancies could not be revealed in the other cases, which was associated to the large voxel size exceeding the mass size. There was a drastic fall in the signal-to-noise ratio with smaller voxel sizes. Furthermore, higher choline levels were determined in 9.5% of the fibroadenoma cases. Comparison of MRS findings before and after contrast injection revealed the advantage of the latter, which is primarily attributed to the more accurate voxel position on the tumor than that during non-contrast-enhanced MRS. CONCLUSION: Dynamic intravenous contrast-enhanced MRM is an effective method for the differential diagnosis of breast masses. MRS cannot be included in the standard study protocol for women with breast masses for the present.

[The role of multispiral computed tomography in assessment of viability of the myocardium and prognostication of left ventricular remodeling in patients with ST-elevation myocardial infarction].

Aim of the study was to assess perfusion defect and viability of the myocardium by the method of multispiral computed tomography (MSCT) in patients with ST-elevation acute myocardial infarction (AMI) and to assess their prognostic role in development of remodeling of the left ventricle (LV). We included into the study 117 patients with AMI. MSCT with intravenous contrast enhancement was carried out on days 3-4 and at 12 months after AMI. In the arterial phase we estimated volume of myocardial perfusion defect, LV end diastolic and end systolic volumes (LVEDV and LVESV), and LV ejection fraction (EF). Three types of myocardial opacification were distinguished on tomograms in delayed phase of MSCT: type I - subendocardial residual defect (RD), type II - transmural RD, type III - transmural delayed hyper enhancement (DE). Patients were divided in 3 groups: (1) with subendocardial RD (n=63), (2) with transmural RD (n=28), (3) with transmural DE (n=26). Development of LV remodeling was registered if at repeat MSCT LVEDV increased more or equal 20% from baseline. In patients with signs of viable myocardium (group 1) volume of perfusion defect was substantially smaller than in patients with nonviable myocardium (groups 2 and 3): 1cm3 (0.4-2.4) vs. 7.3 cm3 (5.3-10.0) and 6.3 cm3 (5.0-15.0), respectively, p<0.001. Compared with groups 2 and 3 patients of group 1 more often were female (p=0.04), had inferior MI (p<0.001), and spontaneous reperfusion (p<0.001). After 12 months LV remodeling was registered in 19.3% of patients, all had signs of nonviable myocardium in more or equal 3 LV segments. In patients with perfusion defect more or equal 10 cm3 probability of development of LV remodeling exceeded 50%. Disturbances of perfusion abnormalities and number of nonviable LV segments were main predictors of LV remodeling.

[Comparison of characteristics of atherosclerotic plaques in patients with acute coronary syndrome and stable ischemic heart disease: data of multispiral computed tomography].

AIM: To elucidate possibilities of multispiral computed tomography (MSCT) for assessment of morphology of atherosclerotic plaques in coronary arteries of patients with acute coronary syndrome (ACS) or stable ischemic heart disease (SIHD). MATERIAL AND METHODS: Assessment of internal relief of coronary arteries and composition of atherosclerotic plaques was carried out in 85 patients with ACS and 41 patients with SIHD. MSCT was performed with the use of computed tomograph. Visual assessment included determination of plaque type (calcified, soft, and heterogeneous) and contour (regular, irregular). Quantitative assessment included determination of plaque density and index of remodeling. RESULTS: Among patients with ACS we found 194 plaques (60--soft, 72--heterogeneous, and 62--calcified). Plaques in symptom related compared with non-symptom related arteries had higher index of remodeling (1.4 +/- 0.3 and 1.2 +/- 0.2, respectively, p < 0.0001), and more frequently had irregular contour (60.0 and 12.8%, respectively, p < 0.0005). Soft plaques and plaques with irregular contour prevailed in ACS group (68.0%) while calcified plaques were more frequent in SIHD group (66.4%). Plaques with irregular contour were more frequent and index of remodeling was higher in ACS compared with SIHD group (33.5 vs 7.2%, p < 0.0005, and 1.3 +/- 0.2 vs 1.0 +/- 0.2, p < 0.001, respectively). CONCLUSION: According to MSCT data main characteristics of atherosclerotic plaques in patients with ACS were low density and inclusions of microcalcinates. Specific features of plaques in symptom related arteries were irregular contour and positive remodeling index.

[Myocardium non-compaction].

The left ventricular non-compaction (spongy cardiomyopathy) is a rare, poorly known pathology. Disease according to WHO classification applies to unclassified cardiomyopathy. Clinical picture is nonspecific. Diagnosis is established by means of instrumental techniques such as echocardiography and magnetic resonance imaging. Spongy cardiomyopathy usually affects the left ventricle, right ventricular failure occurs much less frequently. We present a description of the disease in 18 years old girl with signs of myocardial infarction and non-compaction of both (left and right) ventricles.

[The potential of multislice computed tomography for the detection of specific anatomic and topographic features of the facial nerve canal prior to stapedoplasty].

The objective of the present study was to estimate the potential of multislice computed tomography (MSCT) for the detection of specific anatomic and topographic features in the structure of the middle ear and the oval window region prior to stapedoplasty. We analysed the results of MSCT of the temporal bones in 20 patients presenting with otosclerosis (40 observations). All these patients underwent stapedoplasty, and the intraoperative findings were compared with the MSCT data. Specificity and sensitivity of MSCT for the detection of structural abnormalities in the middle ear were estimated at 91.3% and 84.6% respectively. It is concluded that the preoperative MSCT examination of the temporal bones yields the data that allow for the more accurate planning of the succeeding surgical intervention as well as for choosing its optimal strategy and extent, proper instruments, the type and length of the implant (prosthesis), and thereby for avoiding the possible complications and improving the prognosis of the treatment.

[31P magnetic-resonance spectroscopy in cardiac diseases].

Magnetic Resonant spectroscopy (MRS) in the nuclei of phosphorus is the only noninvasive method of studying the state of myocardial energy metabolism does not require the introduction of radiopharmaceuticals. This method uses the signals from the nuclei of 31P contained in such mattered phosphates like phosphocreatine and adenosine triphosphate. MRS can provide an answer to a variety of theoretical and clinical issues in the study of various cardiac diseases. The first is ischemic heart disease, as well as heart failure, hypertrophy of various origins, etc. In addition, the method can be used to control the various treatments, including therapeutic, interventional or surgical. Combined with magnetic resonance imaging of the heart gives information on the anatomy, size, function, perfusion defects, structural changes of the myocardium, as well as about the state of energy metabolism of myocardium.

[Mammographic screening with the assessment of risk factors and incidence of BRCA-associated breast cancer in the Republic of India].

The leading risk factors of breast cancer (BC) were found to affect the efficiency of mammographic screening. The BC screening covered 26 912 women in 2001-2010. Its risk factors were identified using a questionnaire survey. During the BC screening, all the women underwent mammography in the frontal and oblique projections. The BIRADS scale was used to evaluate breast X-ray density. The performed examination revealed that the number of risk factors for BC directly affected its stage. The diagnostic efficiency of screening mammography was found to decline in the groups of patients with high breast X-ray density. The paper provides evidence that it is important to monitor groups of patients having BC risk factors and that it is expedient to estimate breast X-ray density. The frequency of BRCA1/2 gene mutations was determined in patients with BC identified during the mammographic screening. A relationship was found between the diagnosis of end-stage BC and the presence of BRCA1/2 gene mutations.

[Radiodiagnostic methods for dental anomalities].

OBJECTIVE: To determine the capacities of radiologic studies in the examination of patients with dental anomalies. SUBJECT AND METHODS: One hundred and twenty patients with dental anomalies were examined. Conventional X-ray and high-technology radiology techniques (multislice spiral computed tomography (MSSCT) and cone-beam computed tomography (CBCT)) were used. RESULTS: Orthopantomography is the most common method for radiologic examination of patients with dental anomalies. However, X-ray procedures do not provide complete information on the position and status of an abnormal tooth, which is required to define further patient management tactics. While planning the management, MSSCT and CBCT were performed in 56 (46.7%) and 64 (53.3%) patients, respectively. In addition, 72 (60.0%) patients in whom orthodontic treatment had been recommended at the first stage underwent MSSCT or CBCT following 7 months. CBCT showed that 4 (3.3%) patients had dental ankylosis previously undiagnosed by MSSCT. The high-technology radiology techniques could assess the position of a tooth in relation to its important anatomic structures and identify the comorbidity that keeps from being treated. CONCLUSION: MSSCT and CBCT can make in full measure the topical diagnosis of abnormal teeth and hence choose an optimal algorithm for comprehensive treatment of patients.

[Evaluation of myocardial energy metabolism by 31 P-magnetic resonance spectroscopy in patients with hypertrophic cardiomyopathy versus healthy individuals].

OBJECTIVE: To estimate the left ventricular (LV) energy index from the data of 31P-magnetic resonance spectroscopy (31P-MRS) in patients with hypertrophic cardiomyopathy (HCM) versus healthy individuals. SUBJECT AND METHODS: The investigation included 46 persons, including 30 healthy volunteers (Group 1) without cardiovascular diseases and 16 patients with HCM (Group 2). All the persons underwent cardiac magnetic resonance imaging (MRI) and 31P-MRS using a high-field Achieva 3T TX MRI scanner (Philips, Netherlands). ISIS location and adiabatic pulse with iterative shimming were used to collect data. RESULTS: The PC/ATP energy index (a phosphocreatine to adenosine triphosphate ratio) was employed to evaluate myocardial energy metabolism in the patients with HCM. The PC/ATP index was 2.08 +/- 0.35 in Group 1 and 1.32 +/- 3.3 in Group 2 (p < 0.05). CONCLUSION: 31P-MRS may be used to determine the myocardial energy metabolism in patients with HCM.

[Functional multispiral computed tomography of sound-transmitting structures in the middle ear].

The objective of this work was to estimate the potential of functional multispiral computed tomography (fMSCT) for the choice and planning of the treatment strategy and the extent of surgical intervention in the patients presenting with fibroosseous diseases of the middle ear associated with the pathologically altered mobility of the auditory ossicles. Studies with the use of MSCT and fMSCT for the examination of temporal bones in 21 patients (25 observations) provided information about normal CT anatomy of the middle ear and a basis for the development of the fMSCT protocol; moreover they allowed the range of mobility of the auditory ossicles to be determined in healthy subjects and patients with middle ear disorders. It is concluded that fMSCT of temporal bones may be recommended to patients suffering otosclerosis, tympanosclerosis, and adhesive otitis media. The use of this technique improves the accuracy of diagnosis and facilitates the choice and planning of the treatment strategy and the extent of surgical intervention in the patients presenting with middle ear diseases.

[Functional multislice spiral computed tomography of the rectus muscle of the eye in scar changes].

The study deals with the capacities of functional multislice spiral computed tomography (FMSCT) in choosing a treatment policy and planning the tactic and scope of surgery for posttraumatic scar changes in the rectus muscle of the eye. Orbital MSCT and FMSCT were conducted in 15 patients (30 orbits). The findings showed that it was necessary to perform orbital FMSCT in posttaumatic scar changes to evaluate the contractility of the rectus muscles and their involvement in the area where a fracture occurs. Improved diagnosis achieved by FNSCT could optimally choose the tactics and scope of surgical intervention.

[Multislice spiral computed tomography in the planning of transcatheter aortic valve replacement].

Surgical treatment for aortic valve (AV) pathology is an urgent and important problem of modern medicine. The prevalence of valve disease is great and remains steadily high in the population. Due to a large number of patients who cannot undergo open AV surgery, alternative hybrid treatments are recently being actively improved. Multislice spiral computed tomography (MSCT) is mandatory prior to transcatheter AV replacement as the examination results determine if a hybrid treatment can be performed and the access is transfemoral or transapical. MSCT provides the data necessary to determine the sizes and types of AV prostheses. The application of the current systems of 320-640 spiral tomographs will further improve MSCT as the method of choice in examining patients before transcatheter AV replacement.