HEAD AND NECK
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).
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.
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
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
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.
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.
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.
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.
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
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
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.
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.
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 2408-9516 (Online)