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No 5 (2017)
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HEAD AND NECK

8-17 1120
Abstract

Purpose: to investigate the diagnostic opportunities of contrast  magnetic resonance imaging with the effect of magnetization transfer effect in the diagnosis of focal metastatic lesions in the brain.

Materials and methods. Images of contrast MRI of the brain of 16  patients (mean age 49 ± 18.5 years) were analysed. Diagnosis of  the direction is focal brain lesion. All MRI studies were carried out  using the Toshiba Titan Octave with magnetic field of 1.5 T. The  contrast agent is “Magnevist” at concentration of 0.2 ml/kg was  used. After contrasting process two T1-weighted studies were  performed: without T1-SE magnetization transfer with parameters of pulse: TR = 540 ms, TE = 12 ms, DFOV = 24 sm, MX = 320 × 224  and with magnetization transfer – T1-SE-MTC with parameters of pulse: ΔF = −210 Hz, FA(МТС) = 600°, TR = 700 ms, TE = 10 ms,  DFOV = 23.9 sm, MX = 320 x 224. For each detected metastatic  lesion, a contrast-to-brain ratio (CBR) was calculated. Comparative  analysis of CBR values was carried out using a non-parametric  Wilcoxon test at a significance level p < 0.05. To evaluate the  sensitivity and specificity of the techniques in the detection of  metastatic foci (T1-SE and T1-SE-MTC), ROC analysis was used. The sample is divided into groups: 1 group is foci ≤5 mm in size, 2  group is foci from 6 to 10 mm, and 3 group is foci >10 mm. 

Results. Comparative analysis of CBR using non-parametric Wilcoxon test showed that the values of the CBR on T1-weighted  images with magnetization transfer are significantly higher (p  <0.001) that on T1-weighted images without magnetization transfer. According to the results of the ROC analysis, sensitivity in detecting  metastases (n = 90) in the brain on T1-SE-MTC and T1-SE was  91.7% and 81.6%, specificity was 100% and 97.6%, respectively.  The accuracy of the T1-SE-MTC is 10% higher in comparison with  the technique without magnetization transfer. Significant differences (p < 0.01) between the size of the foci detected in post-contrast T1- weighted images with magnetization transfer and in post-contrast  T1-weighted images without magnetization transfer, in particular for  foci ≤5 mm in size, were found.

 

Conclusions
1. Comparative analysis of CBR showed significant (p < 0.001)  increase of contrast between metastatic lesion and white matter on  T1-SE-MTC in comparison with T1-SE.
2. The sensitivity, specificity and accuracy of the magnetization transfer program (T1-SE-MTC) in detecting foci of  metastatic lesions in the brain is significantly higher (p < 0.01), relative to T1-SE.
3. The T1-SE-MTC program allows detecting more foci in comparison with T1-SE, in particular foci of ≤5 mm (96% and 86%, respectively, with p < 0.05).

18-28 1526
Abstract

Clinical case of the patient with nasopharyngeal carcinoma
after stereotactic radiosurgical treatment for the persistent disease after chemoradiotherapyare presented. The diagnostic data of PET/CTwith  18F-Fluoroethyl-Ltyrosine (18F-FET)and MRI with intravenous contrastof head and neck were included in analysis. There was  analyzeda clinical case of differential diagnosis of changes in thetemporal lobe of the brain after stereotactic radiation therapy of  nasopharyngeal carcinoma using PET/CT with 18F-FET. Identified high  diagnostic accuracy in the differential diagnosis of delayed changes in  the brain (tumor or radiation necrosis) after radiation therapy  ofnasopharyngeal carcinoma.

29-38 179412
Abstract

Objective: a comparative “blind” assessment of the thyroid nodules identified by ultrasound, according to the TI-RADS scale in various modifications.

Materials and methods. Retrospective analysis of 149 echograms  of thyroid nodules by three independent experts was performed (the  experience of ultrasound of thyroid ultrasound for more than 7 years).

Results. In solid nodules, high-specific large (more than 94%) and  small (more than 90%) ultrasound signs of thyroid cancer have been identified. The nodes are stratified according to the TI-RADS system: 1 – in the modification J.Y. Kwak et al. (2011), 2 – according to the  proposed system, taking into account small ultrasound signs of  thyroid cancer. High reproducibility of both systems are obtained. In the first system 13.7% of cancer nodes fell into the category of TI- RADS 3 (benign formations), in the second system only 5% of  cancers fell into the category of TI-RADS 3, which is important for  biopsy selection. The sensitivity of the first system was TI-RADS  82.05%, of the second system – 94.87%.

Conclusions. Classification of TI-RADS can be used to interpret the  ultrasound results of thyroid nodules, taking into account both the  main large and small ultrasound signs of cancer. For its validation in  our country, it is necessary to further broad discussion of the proposed TI-RADS system.

THORAX

39-55 1354
Abstract

Atrial fibrillation (AF) is the most common arrhythmia encountered in clinical practice. Сatheter ablation (CA) of arrhythmogenic foci is supposed to be an established treatment option for symptomatic  patients with AF, refractory to antiarrhythmic therapy. Pre-procedural imaging is indispensable for the assessment of left atrium,  pulmonary veins and adjacent anatomy, and facilitates selection of  the ablation strategy to achieve an optimal result and minimize the risk of complications.

Purpose: to evaluate the role of contrast-enhanced MDCT in  patients with AF; also to present the prospects for further  development of this method according to the systemic review of world research data.

Materials and methods. 140 free access articles requested as  “MDCT left atrium”, “MDCT pulmonary veins”, “MDCT atrial  appendage” from 01.2009 until 01.2017 were analyzed in PubMed,  as well as a number of Russianlanguage articles in eLibrary.

Results. This literature review reports and systematizes available  data on epidemiology and mechanisms of AF, represents current  classification. In addition were analyzed advantages of MDCT over  other methods of visualization while planning the CA and follow-up.

Conclusion. MDCT is precise, effective and accessible option, which  satisfies visualization requirements during the preparation for CA.  Moreover, using MDCT in combination with electro-mapping systems  increases safety and effectiveness of the procedure. In postoperative period MDCT can be used for complications diagnostic and results assessment.

ABDOMEN

56-65 1335
Abstract

Objective: to develop a methodology for quantitative assessment of changes in density parameters of pulmonary tissue on the basis of  dynamic CT data, which makes it possible to assess the presence of  the dependence of changes in lung tissue on the time elapsed after  radiation therapy (RT), the dose and volume of irradiated pulmonary tissue.

Materials and methods. Using the data collected by 11 patients  with malignant lymphomas, we developed a new diagnostic  technique for quantitative analysis, which is based on the analysis of the density of pulmonary tissue before and after RT in areas with a  selected range of doses throughout the lung volume. All selected  patients received LT in the chest region, using 3D-planning, fractions of 2Gy and total focal doses of 13–56 Gy. Also, each patient had at least two CT examinations (a total of 25 studies in the Dicom- format). The first CT scan was performed before LT, repeated –  within 2–7 months after the end of RT.

Results. In 6 patients, control CT examinations were performed  2.1–2.8 months after RT. As a result, a quantitative increase in the  density indices in the range from +12 to +62 HU in regions of the  lungs irradiated at a dose of more than 19 Gy was noted, different  from the control areas. The volume of these areas of the lungs was  from 16% to 30% of the total lung volume, and the volume of  regions with the maximum values of density growth – from 7% to  14%. These changes in density are below the “visual” threshold. In  control areas, the density change varied from −15 HU (increased airiness) to + 8 HU. According to the data of other CT  studies performed later than 3 months after RT, the reverse  development of changes characterizing the early radiation reaction was observed.

Conclusions. A series of CT studies performed before and at various intervals after RT allows quantitative assessment of the dynamics of the indices of the density of irradiated pulmonary tissue, which is  necessary for an objective assessment of the severity of early  radiation-induced injuries of pulmonary tissue sites, depending on  the dose. A study of the dynamics of these changes in pulmonary  tissue density over time with RT and the connection of this indicator  with the baseline data may allow one to predict radiation-induced damage to the lungs on the one hand, and on the other, to evaluate individual radiosensitivity.

66-81 1678
Abstract

Objective: to compare diagnostic effectiveness of whole body  diffusion-weighted imaging (DWI), other magnetic resonance  imaging (MRI) pulse sequences and iliac wing trephine biopsy in the  diagnosis of focal and diffuse bone marrow (BM) involvement in patients with lymphoma.

Materials and methods. Prospective study included 130 patients  with lymphoma who underwent whole-body MRI-DWI and iliac wing  trephine biopsy before treatment (64 (49,2%) men, 66 (50,8%)  women, middle age 43,3 ± 16,3 years, interval of 18–79 years).  Hodgkin's lymphoma (HL) was at 57 (44%) patients, non-Hodgkin  lymphomas (NHL) – at 73 (56%). Diagnostic effectiveness of T1- weighted images (T1-WI), STIR, DWI and FIESTA was analyzed. BM  apparent diffusion coefficient (ADC) values were measured.

Results. BM involvement was found in 42 patients, including 9 with  HL and 33 with NHL. In HL, BM involvement was only focal. Diffuse  involvement occurred more often (64%) in the NHL as compared to  focal one. In focal involvement, all pulse sequences showed high  diagnostic sensitivity (90–100%), BM biopsy sensitivity was 33%  only. The proposed new criterion for the diagnosis of diffuse BM involvement in NHL – diffuse signal increase of the spine on DWI  above renal parenchyma – has the highest sensitivity (90%) compared to T1-WI and STIR (67%) and FIESTA (71%) (p < 0.05).  In NHL, the ADC value ≤0.575 • 10−3 mm2/s discrimi nates cases  of diffuse involvement and absence of BM involvement with a  sensitivity of 86% and a specificity of 68% (p < 0.0001). In HL, the  diffuse BM signal increase on DWI is not indicative of involvement.

Conclusion. All pulse sequences showed high effectiveness in the  diagnosis of focal BM involvement in patients with lymphoma, iliac  wing biopsy effectiveness was low. The proposed new DWI criterion  for diagnosing diffuse BM involvement in NHL is the most sensitive  one. A new algorithm based on whole body MRI-DWI for the  diagnosis of BM involvement allows to reduce the need for BM biopsy without reducing the diagnostic effectiveness.

82-93 2523
Abstract

Purpose: the aim of this study was to evaluate the reliability
of ARFI elastometry for diagnosis of fibrosis severity stages in patients with chronic viral hepatitis.

Material and methods. ARFI elastometry measurements were  done in 103 patients. Mean age of patients was 39.2 ± 10.8 years.  The study included 11 patients with HBV chronic hepatitis, 87  patients with HCV chronic hepatitis and 5 patients with В+D chronic  hepatitis. Liver stiffness was measured using ARFI elastometry with  following liver biopsy which was made 1–2 after US study and  assessed according to the METAVIR score. Control group included 32  patients (20 (62.5%) volunteers and 12 (37.5%) potential liver  fragment donors). Mean age of patients was 26.9 ± 5.3 years. None  of the healthy subjects had a history of gastrointestinal, pancreatic or hepatic disease; all patients had a normal results of laboratory tests.

Results. Significant correlation (r = 0.74, р < 0.001) was found  between ARFI measurements and liver fibrosis stages. The values of  ARFI elastometry for various stages of fibrosis were: F ≥ 2 – cut-off  > 1.36 m/s (AUROC – 77%, sensitivity – 65.9%, specificity – 79%),  F ≥ 3 – cut-off > 1.36 m/s (AUROC = 95%, sensitivity – 95,5%,  specificity – 81.5%), F = 4 – cut-off > 1.66 m/s (AUROC – 97%, sensitivity – 93.3%, specificity – 100%). Liver stiffness  measurements in stages F0–F2 reliably differ from stages F3–F4 (1.25 ± 0.18 m/s vs 2.0 ± 0.52 m/s, р < 0.05).

Conclusion. ARFI elastometry is reliable diagnostic method for liver  fibrosis detection in stages F ≥ 2. The best performance of this  method was shown for the prediction of severe fibrosis and cirrhosis.

94-98 6030
Abstract

The purpose: the estimation of a computed tomography
(CT) signs of hepatic calcification hemangioma. 

Material and  methods. Retrospectively results of CT with bolus contrast  enhancement for examination hepatic calcified lesions of the 36  patients were analyzed. 

Results. As a basis for the retrospective  analysis, the semiotic signs of patients, in which the hemangioma calcification developed during the dynamic CT  monitoring, were used. As shown by the analysis, the center of  calcification in combination with the cloisonne structures leading the arterial vessel, the decrease in the area of the focal lesion in the portovenous phase due to the vascular structures along the periphery of the focus are the criteria of calcified  hemangioma. In 11 of 36 patients, calcified foci in the liver turned out to be hemangiomas.

Conclusion. More than 30% calcifications in the liver detected at CT can be calcification hemangioma.

99-105 1034
Abstract

Colonic volvulus is responsible for 4–5% of all cases of intestinal  obstruction and most often found in the sigmoid colon, in elderly  patients with chronic constipation, where patients develop a large  redundant sigmoid colon and with a violation of diet. Twisting and  compression of mesenteric blood vessels leads to disruption of  intestinal wall nutrition followed by necrosis. Most cases of volvulus  require the surgical treatment. Abdominal radiography (barium  enema, MSCT) is frequently obtained as the initial diagnostic  imaging and has characteristic appearances. We present a case of  MRI diagnosis of the colon volvulus after the closure of the  transverse loop colostomy after low anterior resection for rectal  cancer. The cause of the volvulus was the twisting of the mobilized  part of colon with the mesentery when it was lowered into the pelvis. The protective transverse loop colostomy caused the absence of  clinical manifestations. After its closure patient was present the  clinical features of bowel obstruction and the appearance of MR  symptoms typical for this pathology. A retrospective analysis of MR  tomograms obtained before the closure of the transverse loop  colostomy, allowed revealing of signs of its subclinical ischemia. This  case demonstrates the possibilities of MRI in identifying both the  typical symptoms of colon volvulus and the signs indicating the possibility of colon twisting in patients after low anterior rectal resection, examined before closing the transverse loop colostomy.

SMALL PELVIS

106-111 1193
Abstract

There is no doubt about the prevalence rate of benign prostate  hyperplasia. Currently, transurethral prostate resection (TUR) is the  main method of surgical treatment. To clarify the degree of possible  intraoperative bleeding, we assume the application of pre-hospital  transrectal ultrasonic prostate examination (TRU) with vascular  Doppler and 2D Shear Wave elastography.

The aim: to evaluate the possibilities of preoperative complex TRU  prostate examination in forecasting of the expressed intraoperative bleeding.

Materials and methods. The study included the results of a survey of 242 patients in the urological Department of the road clinical hospital of Rostov-on-don in the period from 2016 to 2017, which  had undergone TUR of the prostate. All patients before the operation was performed prostate transrectal ultrasonography (TRU) with  Doppler and 2D Shear Wave Elastography (2DSWE). Depending on  the amount of blood loss determined after surgery, all patients were divided into three statistically (p < 0.001) significant groups (р  < 0.001). All TRU examinations were made with ultrasound system  Aixplorer (France). During Doppler sonography, maximal linear blood flow velocity (Vmax) in capsular arteries (CA), in “surgical capsule”  arteries (SCA) and in the paraurethral artery (PuA) was measured. During 2D Sheare Wave elastography (2D SWE) stiffness of tissues  was measured (in kPa) in symmetric areas of both lobes of  peripheral zone (PPZ), central zone (CZ), and transitory zone (TZ) of prostate

Results. Significant (p < 0.001) correlation of blood loss with  reduction of hemoglobin level, as well as with Vmax CA, Vmax PuA,  tissue stiffness TZ and areas on the border with the surgical capsule  revealed. The ROC analysis showed, that sensitivity and specificity of predictions of severe intraoperative blood loss, when using a cut-off  for the Vmax of the blood flow in CA more 18.7 cm/s, was  respectively 87.2% and 94.4 per cent; when using a cut-off for the  Vmax of the blood flow in the basin PUA over 24.2 cm/s –  respectively of 76.6% and 78.5%; when using a cut-off of stiffness  of the tissues TZ less of 39.8 kPa – respectively 100% and 95.4%: when using a cut-off of stiffness of the tissues at the border of the “surgical capsule” less than the 38.1 kPa – respectively 89,4% and 90,8%.

Conclusion. The use of cut-off Vmax values for the blood flow in the paraurethral and capsular arteries, as well as the use of cut-off  values for tissue stiffness in the prostate transitory zone of prostate  and in the surgical capsule area, may be an effective means of  forecasting of expressed intraoperative bleeding. The data presented is recommended to take into account the operating surgeon during  the selection of patients for operative benefits.

BONES AND JOINTS

112-123 2097
Abstract

Evaluation of the rotator cuff muscles is of value for surgical indications and successful postoperative prognosis. Ultrasound is  widely used for detection of rotator cuff tears, but it’s role in  evaluation of the rotator cuff muscles is not yet defined. A new  method Fusion MRI/US with elastography is able to show differences  in tissue stiffness, and a simultaneous combination of two methods  helps to overcome limitations from US – narrow field of view, and  from MRI – impossibility for real time examination and low space resolution.

Purpose. To investigate diagnostic performance and interobserver  reliability of US elastography and to study possibilities of Fusion  MRI/US technique in grading fatty degeneration and atrophy of the supraspinatus muscle.

Materials and methods. 72 patients from 128 with shoulder pain  and disability with written diagnostic confirm were specially selected  for the study with US elastography and MRI and 29 patients were  enrolled for Fusion MRI/US study. Oblique sagittal scans through the  supraspinatus muscle were performed during US elastography study  in the standard manner for comparance with MRI. The amount of  fatty degeneration was graded according to the modified Goutallier five-point scale, with use of a 3-point scale – with US elastography.  US results for grade of atrophy and fatty degeneration were  retrospectively reviewed by 2 blinded to each other results experts.  Sensitivity and interobserver reliability was estimated.

Results. The sensitivity of standard US in comparance to US  elastography in assessment of muscle atrophy with the reference to  MRI was 53% and 76%, respectively. The sensitivity of US and US  elastography increased with increasing of the grade of muscle  atrophy. The sensitivity of US and US elastography in detection of  fatty degeneration was slightly better 65% and 85%, respectively.  US elastography were more sensitive in evaluation of fatty  degeneration in full thickness than in partial thickness rotator cuff tears. In all cases of full thickness tears US with elastography had a 100% sensitivity in assessment of atrophy and fatty degeneration in the reference to MRI. While in partial tears  the sensitivity decreased to 66%. The agreement between MRI and US elastography for the grade of fatty degeneration of the  supraspinatus was substantial (kappa = 0.78). The interobserver  reliability for US was fair (kappa = 0.41), and for US elastography  substantial (kappa=0,71).

Conclusion. Sonoelastography helps to increase the diagnostic  performance of US in identifying and grading fatty degeneration and  atrophy of the supraspinatus. US with elastography can be used as a  primary modality for fatty changes and atrophy of the supraspinatus.

124-130 1535
Abstract

Сomputed tomography (CT) is widely used in the diagnosis of  degenerative pathology of the lumbar spine, but the relationship  between clinical manifestations of lumbar stenosis and its anatomical prerequisites has not been sufficiently studied to date.

The objective: to determine the significance of the morphometric  parameters of lumbar stenosis according to CT scans and to  establish their relationship with the prevailing symptoms of the disease.

Material and methods. Seventy-five consecutive patients with  clinically significant lumbar stenosis who underwent CT scan before  surgery were enrolled in this study. The average values of thirteen  different morphometric parameters were calculated at LIII–SI levels of the intervertebral discs and of the pedicels in the axial and sagittal views. The possibility of classification of clinical observations and the correlation of morphometric parameters with the clinical forms of lumbar stenosis were investigated using discriminant and logistic regression analysis.

 

Results. CT scan with high probability allocates patients with  predominant symptoms of neurogenic claudication or bilateral  radiculopathy. The most significant morphometric predictors of this  clinical group are the depth of the lateral recesses and the cross-sectional area of the spinal canal.

Conclusion. CT scan significantly expands the informative value of  magnetic resonance imaging and can be used in planning the  decompressive stage of the surgery intervention in patients with lumbar spinal canal stenosis.

131-141 939
Abstract

The hundreds thousands total hip arthroplasties (THA) annually  performed around the world with the number of revision procedures  estimated around 10%. Dual-energy X-ray absorptiometry (DEXA)  allows to control projectional bone mineral density (BMD) around hip stem dynamically with minor radiation exposure and in a cost-effective way. In routine practice there is a monthly interval between investigations that does not allow to evaluate activity and trends in  short weekly oscillations of bone metabolism in peri-prothetic areas.  Projectional BMD oscillations in peri-prosthetic zone after total hip  arthroplasty in chrono-biological manner evalua ted for the first  time. Therefore chronobiologic approach opens new opportunities for prognosis of tendencies in structural and functional skeleton  reorganization in peri-prothetic zone after THA but there is need in  further research that could give more insight.

INFORMATION



ISSN 1607-0763 (Print)
ISSN 2408-9516 (Online)