[Comparative survey of radiation doses to patients in computed tomography in a federal hospital]

OBJECTIVE

to analyze radiation exposure due to computed tomography (CT) of brain, chest, abdomen and pelvis in a large multi-field federal hospital and feasibility of low-dose CT-examinations.

MATERIAL AND METHODS

Retrospective analysis was performed using data from electronic patient records and PACS from a single multi-field hospital. Data were obtained from 1626 records of patients (794 men, 832 women; age range 17-93) scanned with 3 MDCT during one year. CT-examinations of good quality were selected, volumetric CT dose index (CTDI) and dose-length product (DLP) were collected for each of them. The effective doses (ED) were calculated using the normalized coefficients according to Russian Guidance. RESULTS. Number and structure of CT-examinations for the years 2012-2014 in a multi-field hospital were analyzed. The mean effective dose (M ± m) values with/without contrast medium (respectively), according to anatomical areas were as follows: brain--2.34 ± 0.03/3, 52 ± 0.23, chest--4.83 ± 0.11/11.02 ± 0.82, abdomen-pelvis--9.81 ± 0.40/36.6 ± 1.17, chest-abdomen-pelvis - 12.41 ± 0.79/35.63 ± 1.81 mSv. CONCLUSION. Results of this study give an example of CT dose values and distribution in a multi-field hospital. They are compa- rable with reference levels published of other authors. This expe- rience should be expanded for creation of CT national reference values and for co-operation with international initiatives (EUROSAFE projects).

[Magnetic resonance imaging of the liver and spleen in the diagnosis of storage diseases]

Storage diseases (thesaurismoses, storage reticuloses) are the common name of a large group of hyperplastic non-leukemic diseases characterized by congenital or acquired metabolic disturbances and abnormal accumulation of metabolic products in blood and/or cells of different organs and by hyperplasia of mononuclear phagocyte elements in the liver, spleen, bone marrow, lymph nodes, and other organs, which makes the diseases systemic. Among the imaging techniques for diffuse liver diseases, ultrasonography and X-ray computed tomography are most commonly used for their diagnosis and follow-up. Magnetic resonance imaging (MRI) has the highest sensitivity and specificity in diagnosing liver diseases. The paper considers the current MRI procedures that are used to diagnose storage diseases and to quantify found changes. For Gaucher's disease, the potentials of novel techniques, such as MR spectroscopy, diffusion-weighted imaging (DWI), and chemical shift imaging (Dickson's method) for the estimation of revealed changes, are described. For hemochromatosis, the contribution of T2 WI to the quantification of iron overload in the liver parenchyma is depicted, which is an alternative invasive procedure in its determination. Incorporation of MRI into the examination algorithm for patients with storage diseases will be able to improve the detection of these rare diseases and to monitor the efficiency of performed therapy.

[Role of multislice computed tomography in the differential diagnosis of right iliac tumors and inflammatory diseases]

OBJECTIVE

To determine the capabilities of multislice computed tomography (MSCT) in the differential diagnosis of tumors and inflammatory diseases of the cecum, appendix, and ascending colon.

MATERIAL AND METHODS

The investigation analyzed the complete data of medical records and the results of diagnosis in the patients admitted in 2009 to 2013 to the Treatment and Rehabilitation Center for right iliac pains. The results of MSCT were compared with those of histological verification.

RESULTS

The sensitivity and specificity of MSCT for diagnosing right iliac tumors were 97.6 and 97.8%, respectively. Those of MSCT for diagnosing right iliac inflammatory diseases were 95.1 and 97.3%, respectively. The investigation showed that the accuracy of MSCT for diagnosing right iliac tumors and inflammatory diseases was 94.1%.

CONCLUSION

MSCT is the method of choice in the diagnosis and differential diagnosis of right iliac tumors and inflammatory diseases.

[HEALTH PREDICTION INDICES OBTAINED WITH LOW-DOSE COMPUTER TOMOGRAPHY SCANS]

Purpose of the investigation was to make prognostic estimations of reductions in somatic morbidity and temporal disability, and tumor pathology using low-dose computer tomography (CT) scans and to compare with standard protocols. Mean effective radiation doses were determined based on the results of 1627 diagnostic CT investigations made in 2012-2014 at the Treatment and Rehabilitation Center of the Russian Ministry of Health. Low-dose CT scans of the head and thoracic, abdominal and small pelvis organs were obtained on a GE Discovery CT750 HD, and with the help of the ASIR and MBIR algorithms of iterative reconstruction. In comparison with a standard dose, a single CT scan with a dose reduced by 10-12 mSv predicts a decrease in total morbidity by 0.84-5.52% and temporal disability by 0.55-1.65% per 100 employees over a year; total risk of tumors and genetic effects reduced in 5 to 10 times, which may be equal to 40-90 cases per 100,000 of 30 y.o. males.

[Structured radiology reports]

The paper reviews the problem of using structured radiology reports. Their salient features are as follows: to work out a protocol in accordance with some pattern, to divide it into subheadings arranged consecutively and logically and broken down by main anatomical structures, types of disease, and study, and to use standardized terminology. The RSNA proposed RadLex system is the most known example of structured reports. The experience in using these protocols has shown that the latter may improve the clearness and informative value of roentgenologists' opinions and alleviate their understanding by physicians of other specialties. However, the systems of writing the structured radiology reports have a number of constraints for the time being, which interfere with their wide clinical introduction. Nonetheless, their use is substantially increasing in the years ahead.

[Capabilities of computed tomography to evaluate polymorphic changes in destructive pancreatitis]

OBJECTIVE

To determine whether the lower-density pancreatic parenchymal areas detected by a computed tomography (CT) study in patients with acute pancreatitis correspond to the necrotic portions of the gland or whether these changes may be reversal.

MATERIAL AND METHODS

The investigation covered 25 patients who had undergone or dynamic CT studies made at different time intervals. Two independent investigators with 4 and 19 years of experience retrospectively analyzed the results of both CT studies. Target estimation was made of the extent (volume) of and CT density changes in the hypodense areas of the gland parenchyma.

RESULTS

Seven (28%) of the 25 patients were noted to have higher CT density in the areas that had decreased density during primary CT studies (more than a 30 HU increase was rated as significant). There was a statistically significant difference between the patient groups when comparing the extent of hypodense areas and the difference in CT density (t-test, p = 0.006); Mann-Whitney U-test, p = 0.01 for extent difference and t-test, p = 0.00; Mann-Whitney U-test, p = 0.00 for CT density difference. There was also a correlation between the extent of hypodense areas and the difference in their CT density (Pearson: r = -0.533, p = 0.006; Spearman: r = -0.636, p = 0.001).

CONCLUSION

The results of our investigation may suggest that the lower-density pancreatic parenchymal areas cannot always correspond to necrotic changes and may be reversible.

[Cardiac magnetic resonance imaging in the diagnosis of acute myocarditis: a clinical case and a review of literature]

The clinical manifestations of myocarditis are extremely variable and it may commonly manifest as acute myocardial infarction. The diagnosis of acute myocarditis is frequently empiric and substantiated by the clinical picture of the disease, ECG changes, elevated enzyme levels, and the lack of any data on coronary heart disease. Until recently, endomyocardial biopsy has been considered to be the most accurate diagnostic method. However, endomyocardial biopsy has a low sensitivity and is associated with the high risk of complications. This paper describes a clinical case of a patient with cardialgias occurring after acute respiratory viral disease, with ST segment elevation, and higher levels of cardiospecific enzymes. The diagnosis of myocarditis was verified by contrast-enhanced cardiac magnetic resonance imaging.

[Diagnostic efficiency of multidetector computed tomography in patients with tongue cancer]

OBJECTIVE

To determine the capacities of multidetector computed tomography (MDCT) to diagnose tongue cancer.

MATERIAL AND METHODS

Intravenous bolus contrast-enhanced MDCT was performed in 40 patients with tongue cancer diagnosed during complex clinical and instrumental examination. In all cases, the tumor had a structure of squamous cell carcinoma of varying grades. The results of MSCT were compared with the data of surgery and cytological and histological examinations. Tongue tumor accumulation of a contrast agent was qualitatively analyzed.

RESULTS

In 38 (85%) patients, the tongue tumor actively accumulated the contrast agent and was clearly differentiated in the presence of unaffected portions of the tongue and other adjacent anatomical structures, such as mouth floor, oropharynx, and larynx. Only in two cases, the tumor failed to significantly accumulate the contrast agent, which was associated with that there were massive decay areas in its structure. The sensitivity, specificity, and accuracy of MDCT in the diagnosis of tongue cancer were 95, 80, and 87.5%, respectively. MDCT could reliably differentiate changes in tongue cancer from non-tumor diseases. The result of constructing the curve of diagnostic errors became the following values: the area under the curve was 0.875 and the P-value (Asymptotic Sig.) was 0.0001.

CONCLUSION

Intravenous bolus contrast-enhanced MDCT has a high diagnostic efficiency in identifying tongue cancer. The technique can establish the location of a tumor and to reveal the extent of the process to the nearby organs.

[Comparison of low- and high-concentration (270 and 320 mg I/ml) iso-osmolar iodinated contrast media in coronary CT angiography: a randomized prospective single-center blinded study]

OBJECTIVE

To compare the image quality at coronary multidetector computed tomography (MDCT) using low-dose and low-iodine protocol study in comparison with the standard protocol.

MATERIAL AND METHODS

In study included 60 patients undergoing coronary computed tomography angiography. All examinations were performed with 64-row MDCT using prospective ECG-gating and ASIR 40%. 30 patients were examined using a low-concentration (Iodixanol, 270 mg I/ml) iodinated contrast medium and low tube voltage (80 kV) (group 1), 30 patients--using of high-concentration (Iodixanol, 320 mg I/ml) iodinated contrast medium and standard tube voltage (120 kV) (group 2). Image quality of coronary arteries was evaluated using a four-point grading scale, images were randomised. Intra-arterial density was measured for the proximal and distal segments of left anterior descending artery (LAD) and right coronary artery (RCA).

RESULTS

Age, heart rate, BMI and scan parameters were not statistically different between the two groups. Analysis of coronaries visualization revealed the same image quality for group 1 and group 2 (image quality scores were 1.28 ± 0.28 vs. 1.34 ± 0.29, p = 0.4). There was no significant difference between mean enhancement values in the distal segments of RCA and LAD for the two groups. Intraarterial density for proximal LAD and proximal RCA for the nazpyara, umepamuenas group 2 were significantly lower (p < 0.05) than those values for the group 1. Conclusion. Theuse of low-dose and low-iodine protocol can be beneficial for patient safety and or image quality ithout loss of diag- stic information.

[Capabilities of magnetic resonance imaging to diagnose infiltrating pelvic endometriosis]

Deep infiltrating endometriosis is a disease in reproductive-aged women, resulting in varying chronic pelvic pains and infertility, which requires surgical treatment. Objective--to determine the capabilities of magnetic resonance imaging (MRI) to diagnose pelvic endometriosis and to elaborate an optimal scanning protocol if this disease is suspected. Small pelvic MRI has a high accuracy in the diagnosis of endometriosis and can visualize most endometrioid implants, including those that are located under adhesions and in the subperitoneal regions. Just the same, a radiodiagnostician should not forget that MRI is of low informative value in identifying bowel endometriosis. Hence, when diagnosing deep infiltrating endometriosis, MRI should be complemented with transvaginal ultrasonography to detect endometrioid implants on the bowel walls as the informative value in this aspect is above.

[Radiology report: past, present and future]

The analysis of literature data showed that the creation and implementation of a new form of radiology reports into clinical practice is an actual problem of modern medicine. Although imaging modalities have undergone dramatic evolution over the past century, radiology reporting has remained largely static, in both content and structure. In recent years the necessity to create a structured reporting is widely discussed in the literature. A universal format of radiology report hasn't been found yet. The standard of reporting system is absent, a wide variety of styles in radiology reporting currently exists. The challenging goal is improvement of existing protocols and creation of a new form of radiology reports--the protocols of the future.

[Clinical use of proton magnetic resonance spectroscopy in brain tumors and adjacent tissues]

Magnetic resonance spectroscopy (MRS) is a noninvasive technique to measure the concentration of chemical substances, which estimates biochemical changes in health and different diseases in vivo. The technique opens up a wide range of possibilities for both primary diagnosis and evaluation of the efficiency of further treatment--medical or surgical one. This review of literature is dedicated to proton MRS used in different tumors of the brain, its tunics, and adjacent nerves. It contains and systematizes data related to the problems of primary diagnosis, differential diagnosis, and evaluation of the efficiency of treatment for tumors and gives references to both basic researches in this area and recent investigations.

[Use of multislice spiral computed tomography to diagnose and control pulmonary complications in intensive care unit patients after neurosurgical interventions]

OBJECTIVE

To perform a multifactorial analysis of the association of the development of complications in neurologic intensive care unit patients in the early (on days 1-3) postoperative period and with surgical conditions, mechanical ventilation parameters, and risk factors.

SUBJECT AND METHODS

The results of multislice spiral computed tomography (MSCT) of the chest and brain were analyzed in 80 patients (34 men and 46 women; mean age, 52 +/- 13 years).

RESULTS

In the study patient group, the incidence of pulmonary edema and pneumonia was not found to depend on the type of neurosurgical intervention and that of an inhaled anesthetic. There was a significant (p < 0.05) relationship of the development of pulmonary edema to anesthesia duration exceeding 6 hours and an increase in the risk of lung pathology in the presence of extrapulmonary complications in patients with high body mass index.

CONCLUSION

Some pulmonary complications in neurosurgical patients are potentially preventable. Early postoperative chest MSCT in neurosurgical patients is essential to timely diagnose lung pathology.

[The normal anatomy of the tongue and adjacent organs according to the data of computed tomography and magnetic resonance imaging]

The paper presents the normal anatomy of the tongue and adjacent organs according to the data of computed tomography (CT) and magnetic resonance imaging (MRI). Tomographic diagnostic techniques have been proved to be of highly diagnostic value in assessing the anatomy of the tongue and adjacent organs. The authors describe the advantages of CT and MRI over standard clinical and instrumental examination in assessing the anatomic features of the lingual area.

[Use of dual-energy computed tomographic angiopulmonography in patients with chronic thromboembolic pulmonary hypertension before and after pulmonary artery thromboendarterectomy]

OBJECTIVE

To estimate the contribution of dual-energy computed tomographic (CT angiopulmonography t o a diagnostic algorithm in patients with chronic thromboembolic pulmonary hypertension (CTEPH) and its role in the evaluation of postoperative changes.

MATERIAL AND METHODS

CT angiopulmonography was performed on the 64-slice Discovery HD 750 system (GE Healthcare) using the dual-energy scanning mode (140 and 80 kV). The examination results in patients with CTEPH were analyzed.

RESULTS

All the patients were found to have typical CT signs of CTEPH: abnormal contrast enhancement of the pulmonary arteries, their dilatation and tortuosity; signs of right cardiac overload: right ventricular dilatation and/or hypertrophy, bronchial artery dilatation, decreased peripheral vascular pattern, mosaic pulmonary perfusion, and wedge-shaped perfusion defects on the iodine maps. Mosaic pulmonary perfusion areas were also found in all the patients. Perfusion defects were more clearly visualized when dual-energy CT by constructing iodine perfusion maps was used. Analyzing the perfusion maps in 6 patients operated on revealed a 20-50% reduction in perfusion deficit.

CONCLUSION

Information on the vascular bed and pulmonary perfusion may be obtained in patients with CTEPH within one investigation, which is important to plan surgical treatment. Construction of iodine pulmonary perfusion maps allows evaluation of perfusion recovery after artery thromboendarterectomy.

[Diagnostic value of magnetic resonance imaging in the differential diagnosis of acoustic neuroma and meningiomas of the cerebellopontine angle]

OBJECTIVE

To estimate the diagnostic value of differential diagnostic criteria for acoustic neuromas and meningiomas of the cerebellopontine angle in the use of standard magnetic resonance imaging (MRI) modes.

SUBJECT AND METHODS

The study enrolled 39 patients aged 54 +/- 8 years who had histologically verified acoustic neuromas (n=26) and meningiomas (n=13) of the cerebellopontine angle. MRI scans were compared in the outline and location of a tumor and its signal intensity and uniformity. The quantitative standardized coefficient of tumor signal intensity values was calculated by dividing of the latter by those of cerebrospinal fluid in the lateral ventricles and pons cerebelli.

RESULTS

The acoustic neuromas and meningiomas of the cerebellopontine angle exhibited differences in indicators, such as a wide base, the rate of penetration into the internal acoustic meatus, and heterogeneous contrast enhancement on T2-weighted images (T2-WI). The adjacent meninges were different in contrast. Neuromas were hyperintense to the pons varolii on T2-WI and had a low standardized coefficient of cerebrospinal fluid (1.73 +/- 0.3) and the pons (0.73 +/- 0.09) on T1-weighted images (T1-WI). Meningiomas were isointense to the pons varolii on T2-WI had a higher standardized coefficient of cerebrospinal fluid (2.23 +/- 0.36) and the pons (0.86 +/- 0.08) on T1-WI. ROC analysis determined the boundary values for the coefficients with the highest specificity.

Magnetization and spin gap in two-dimensional organic ferrimagnet BIPNNBNO

A magnetization process in the two-dimensional ferrimagnet BIPNNBNO is analyzed. The compound consists of ferrimagnetic (1,1/2) chains coupled by two sorts of antiferromagnetic interaction. Whereas the behavior of the magnetization curve in higher magnetic fields can be understood within a process for the separate ferrimagnetic chain, the appearance of the singlet plateau at lower fields is an example of non-Lieb-Mattis type ferrimagnetism. By using the exact diagonalization technique for finite clusters of size 4 × 6, 4 × 8 and 4 × 10 we show that the interchain frustration coupling plays an essential role in stabilization of the singlet phase. These results are complemented by an analysis of four cylindrically coupled ferrimagnetic (1,1/2) chains via an Abelian bosonization technique and an effective theory based on the XXZ spin-1/2 Heisenberg model when the interchain interactions are sufficiently weak/strong, respectively.

[Endometrial cancer: preoperative staging. The informative value of ultrasound study versus magnetic resonance imaging]

OBJECTIVE

to prospectively study and compare the capacities of magnetic resonance imaging (MRI) and ultrasound study (USS) in the preoperative assessment of the extent of endometrial cancer.

SUBJECTS AND METHODS

The study covered 50 patients with FIGO stages IA-IIIA endometrial cancer. A week before surgery, all the patients underwent small pelvic MRI and USS. The results of MRI and USS were compared with the data of a postoperative histological study.

RESULTS

The diagnostic value of MRI in preoperatively assessing the local extent of endometrial cancer was 82%, including its sensitivity, specificity, and accuracy; the prognostic value of a positive result and a negative one was as much as 94 and 56%, respectively. The accuracy, sensitivity, and specificity of USS were 70, 72, and 64%, respectively. Its prognostic value of a positive result and a negative one was 84 and 47%, respectively.

CONCLUSION

In this study, MRI versus USS showed a higher diagnostic efficiency in the preoperative staging in patients with endometrial cancer. The former promotes the optimization of assessment of the local extent of the tumor, including the depth of myometrial invasion and the spread into the cervix uteri, which affects the algorithm and policy of treatment for endometrial cancer.

[Radial diagnosis MRT and MSCT in assessing the outcomes of surgical correction for complicated congenital heart defects: discordant atrioventricular connections with double outlet right ventricle]

Discordant atrioventricular connection with double outlet right ventricle is a rare complicated congenital heart defect (CHD) requiring accurate diagnosis and appropriate correction. Magnetic resonance imaging (MRI) and multiple spiral computed tomography (MSCT) were used to assess long-term outcomes of the «classical» repair of the double outlet right ventricle in a patient presenting with discordant atrioventricular connection. Using a modified segmental approach provided all necessary anatomical evidence concerning the condition of the heart, major vessels, and an extracardiac pulmonary valve-containing conduit. MSCT made it possible to evaluate the degree of calcinosis and stenosis of the conduit and to visualize the coronary arteries. MRI was employed to assess the pressure gradient at the level of stenosis of the conduit, the relationship between the pulmonary and systemic circulation, transvalvular regurgitation, and ventricular contractility. Comprehensive use of present-day tomographic methods of imaging made it possible to obtain complete anatomical and functional information about the condition of the heart, vessels, extracardiac vascular transplant, as well as to reveal complications and determine the indications for a repeat operative intervention.

[Possibilities of decreasing radiation load during MSRT coronarography: using adaptive statistic iterative reconstruction]

AIM

To assess the effective dose of irradiation and quality of the obtained images while using the algorithm of adaptive statistical iterative reconstruction (ASIR).

MATERIAL AND METHODS

A total of 57 patients were examined using by means of computed tomography (CT), coronarography in the mode of retrospective synchronization. In 27 patients we used the filtered algorithm of filtered back projection (FBP) in the postprocessing treatment, in 30 patients - underwent ASIR algorithm. In all patients we measured the level of contrast, noise and signal/noise ratio (SNRs).

RESULTS

There were no significant difference by the level of contrast, noise and SNRs in the two groups of patients. The effective dose of using ASIR was less by 45,9% than while using FBP (8,7 [3,5] mZv and 16,1 [1,4] mZv, respectively, p < 0,0001).

CONCLUSION

Using 40% of ASIR while performing CT coronarography makes it possible to considerably decrease the effective dose of irradiation of patients without loosing los of diagnostic information.

[Successful treatment of massive thrombosis of the vena cava inferior with nephrotic syndrome and chronic bilateral pulmonary artery thromboembolism in a patient with genetic thrombophilia]

A case is reported of a 23-year-old male patient who developed, after severe blunt injury of the lumbar region, massive thrombosis of the vena cava inferior (VCI), both renal veins, bilateral pulmonary artery thromboembolism (PATE), nephrotic syndrome (NS). In spite of anticoagulant therapy, the condition of the patient progressively aggravated for 1.5 year: thrombosis involved the ileac and femoral arteries on the right, thrombus floated in the right atrium with PATE recurrent episodes, pulmonary hypertension reached 120 mm Hg with formation of decompensated cor pulmnonale, proteinuria and hypoalbuminemia deteriorated, anasarca edema developed Multigenic thrombophilia was diagnosed (1 homozygous and 5 heterozygous mutations). A radical one-stage operation was successful: thromboectomy from the VCI, right ileac and left renal veins, thrombendarterectomy from the pulmonary arteries, suture of the interatrial septum defect, installation of cava-filter After the operation pulmonary pressure lowered to 40-45 mm Hg, right heart volume normalized, immunosuppressive therapy with prednisolone and cyclosporine led to nephropathy remission. The discussion covers mechanisms and factors (including genetic) of thrombosis progression, correlations between intravascular thrombosis, NS and chronic glomerulonephritis (possible NS development due to bilateral thrombosis of the renal veins and nephropathy role in thrombosis progression), approaches to conservative and surgical treatment of such patients. Global experience in conduction of pulmonary thrombendarterectomy and thrombectomy from VCI is reviewed (one-stage operations were not described earlier).