Magnetic Resonance Methods Research Articles

Coulometric method with titratable impurity analysis and mass balance method: convert acidimetric purity to chemical purity for SI-traceable highest standard of qNMR (potassium hydrogen phthalate), and verified by qNMR.

In this study, the coulometric method with titratable impurity analysis and the mass balance method were successfully applied in the quantification of the certified reference material of potassium hydrogen phthalate (KHP) with accurate metrological traceability of chemical purity value (99.983% with an expanded uncertainty of 0.024%, k = 2). In contrast to the general coulometric titration method, the coulometric method with titratable impurity analysis enables the conversion of acidimetric purity to chemical purity: The acidimetric purity was determined by coulometric titration method, and then the impurities that may be titrated as principal components were found as far as possible using various methods and the result of deducting these impurities from the acidimetric purity can be considered as chemical purity. The mass balance method also accounted for all possible types of impurities as much as possible to improve the accuracy of the determined result. The accuracy and reliability of the purity results were subsequently verified by a two-step quantitative nuclear magnetic resonance (qNMR) method. This KHP certified reference material was the first hydrophilic internal standard of qNMR (applied in polar solvents) with an expanded uncertainty lower than 0.03%, which will become a major reference standard in the organic chemistry traceable calibration chain, especially when evaluating hydrophilic organic compounds to obtain purity values with very low uncertainty.

Hydrogeological Characterization of Crystalline Bedrock Using Borehole Magnetic Resonance.

We aimed to test borehole magnetic resonance (BMR) method for determining hydraulic parameters (porosity, permeability, and hydraulic conductivity) required for hydrogeological modeling in two distinct crystalline rock environments. These sites comprise Proterozoic basement rocks of different compositions: mafic rocks at the Sakatti mining development site in northern Finland and felsic rocks at the Olkiluoto Island nuclear repository site in southwest Finland. Although BMR is widely used for determining storage and hydraulic properties in sedimentary environments, there have been few studies in crystalline bedrocks. The results indicate that BMR is a suitable tool for studying lithologically and hydrogeologically heterogeneous fractured crystalline bedrocks. It can produce continuous data from hydraulic properties of bedrock in addition to more time-consuming methods such as flowmeter and packer tests and can provide guidance on where to focus additional flow measurements. The intervals display fracture and reduced matrix porosity characteristics, both of which can be enhanced or reduced locally by chemical alteration and by tectonic processes. Flow parameters vary significantly throughout the studied intervals: independently from the lithological composition, these intervals locally display relatively high porosities, and may be correlated to the more intensely fractured and/or brecciated zones. However, due to the heterogeneity in mineralogy, grain/pore arrangement, and the variability of fracture flow-driven transport in each borehole, the challenge remains in finding a unique set of permeability constants for these crystalline rock types. The permeability models could be calibrated by laboratory measurements of the core, and possibly a new permeability model suitable for crystalline bedrock could be created.

Effect of CO2-Brine-Rock Interactions on the Pore Structure of the Tight Sandstone during CO2 Flooding: A Case Study of Chang 7 Member of the Triassic Yanchang Formation in the Ordos Basin, China.

CO2 flooding is an effective technique to enhance oil recovery from tight sandstone reservoirs. The CO2-rich fluid reacts with the in situ minerals and results in the corrosion and precipitation of minerals in the sandstone, affecting the connectivity and morphological features of pores. However, the diagenesis of the tight sandstone is complex, and the structural modification behavior and mechanism in different lithofacies of tight sandstone during CO2 flooding are still unclear. This study combined CO2 flooding, thin-section casting, scanning electron microscopy, nuclear magnetic resonance, X-ray diffraction, and fractal analysis methods to investigate the changes in the pore structure of tight sandstone after CO2 flooding. The results show that the cement of the tight sandstone is complex and diverse. The tight sandstone can be divided into two types of lithofacies: clay cementation (CL) and ferrocalcite cementation (CA). The mineralogical alterations occur differently in each lithofacies of tight sandstone. Alterations in the cement minerals affect the pores morphology of tight sandstone depending on their mineralogical structure and texture, and the CO2 flooding mainly changes the micromorphology and heterogeneity of large pores. Clay minerals dominate the cement in the CL lithofacies of tight sandstone. The dissolution mainly occurs in small pores because the precipitation of new minerals and exfoliation of skeleton particles partially block large pores and transform them into small pores. Thus, the number of small pores of CL lithofacies increases while the number of large pores decreases. Such a phenomenon hinders the increase in porosity and permeability. On the other side, in the CA lithofacies of tight sandstone, the cement is dominated by ferrocalcite, and the dissolution of ferrocalcite is the primary mechanism of mineralogical alteration. As the ferrocalcite dissolution expands, it creates new flow paths, improving the connectivity of pores. The petrophysical properties of CA lithofacies improve significantly after CO2 flooding. There is a crucial need to study the changes in diagenetic characteristics of tight sandstone due to CO2 flooding. Such type of study provides insights related to the improvement and evaluation of the development of tight sandstone reservoirs during CO2 flooding.

Millihertz magnetic resonance spectroscopy combining the heterodyne readout based on solid-spin sensors.

The sensitivities of quantum sensing in metrology and spectroscopy are drastically influenced by the resolution of the frequency spectrum. However, the resolution is hindered by the decoherence effect between the sensor and the environment. Along these lines, the continue-wave optically detected magnetic resonance (CWODMR) method combined with the heterodyne readout was proposed to break the limitation of the sensor's coherence time. The frequency of the magnetic field was swept to match the unknown signal, and the signal can be transformed to a real-time frequency-domain curve via the heterodyne readout, with a frequency resolution of 4.7 millihertz. Using the nitrogen-vacancy (NV) center ensemble in a diamond as the solid-spin sensors, it was demonstrated that the frequency resolution and precision could be improved proportionally to the low-pass filter parameters of Tc -1 and Tc -1.5, respectively. Furthermore, the introduced method performed the sensing of arbitrary audio signals with a sensitivity of 7.32 nT·Hz-1/2@10 kHz. Our generic approach can be extended to several fields, such as molecular structure determination and biomagnetic field detection, where high-fidelity detection properties across multiple frequency bands are required within small sensing volumes (∼ mm3).

A direct nuclear magnetic resonance method to investigate lysine acetylation of intrinsically disordered proteins.

Intrinsically disordered proteins are frequent targets for functional regulation through post-translational modification due to their high accessibility to modifying enzymes and the strong influence of changes in primary structure on their chemical properties. While lysine Nε-acetylation was first observed as a common modification of histone tails, proteomic data suggest that lysine acetylation is ubiquitous among both nuclear and cytosolic proteins. However, compared with our biophysical understanding of the other common post-translational modifications, mechanistic studies to document how lysine Nε-acetyl marks are placed, utilized to transduce signals, and eliminated when signals need to be turned off, have not kept pace with proteomic discoveries. Herein we report a nuclear magnetic resonance method to monitor Nε-lysine acetylation through enzymatic installation of a13C-acetyl probe on a protein substrate, followed by detection through 13C direct-detect spectroscopy. We demonstrate the ease and utility of this method using histone H3 tail acetylation as a model. The clearest advantage to this method is that it requires no exogenous tags that would otherwise add steric bulk, change the chemical properties of the modified lysine, or generally interfere with downstream biochemical processes. The non-perturbing nature of this tagging method is beneficial for application in any system where changes to local structure and chemical properties beyond those imparted by lysine modification are unacceptable, including intrinsically disordered proteins, bromodomain containing protein complexes, and lysine deacetylase enzyme assays.

Spatial characterization of redox processes and speciation of Ru(III) anticancer complexes by 19F magnetic resonance imaging.

The application of CF3-labeled Ru(III) anticancer complexes to magnetic resonance (MR) imaging of tumour tissues is demonstrated. By combining anatomical chemical-shift selective (CHESS) imaging with 19F chemical-shift imaging (CSI) MR methods, we show that oxidation states and ligand-exchange processes of the complexes can be spatially encoded. Measurements on different tissue models, including a human breast adenocarcinoma tumour, validate the application of these complexes as MR theranostics for the sensing and targeting of hypoxia.

Paraffinic oil residues after heating as a basis for fuel

The possibility of reuse of heavy residues (oily sludge) of low-sulfur, highly paraffinic Mangyshlak oils as a basis for fuel with improved environmental characteristics for engines to marine, river and railway transport, gas turbine and boiler plants, steam boilers and industrial furnaces was shown. A variant of the joint application of the methods of nuclear magnetic resonance, laser confocal microscopy and rheology for study of micro- and mesoscopic structure and some physicochemical properties of crude oil products has been developed. It has been shown that preliminary heating to 90 ° C leads to disruption of the structure and hydrogen bonds between oil associates and complexes, increasing sample homogeneity due to precipitation of solid impurities, partial removal of water content, air bubbles and dissolved gases. The addition of medium distillate diesel fractions to preliminary heated oil residues will make it possible to obtain a higher quality version of the fuel with a reduced resinous and asphaltene substances, lower pour point, good energy content and low sulfur content. Thus, valuable energy-containing raw materials can be reused. It should also be noted that the reuse of accumulated oil waste will reduce the harmful effects of landfills, will preserve the natural landscape, and will cut the cost of extracting natural resources.

An Intelligent Denoising Method for Nuclear Magnetic Resonance Logging Measurement Based on Residual Network

Nuclear magnetic resonance (NMR) is an important geophysical technique for the structure and properties measurement of porous media. The small-diameter NMR logging technology has been emerged as a useful tool in terms of evaluating the shallow surface hydrogeological parameters. However, the NMR logging is always suffering from the low signal-to-noise radio (SNR). This paper proposes a denoising network for NMR logging signal based on the combination of the convolutional neural network (CNN) and residual learning, called as Dn-ResNet. Firstly, a large amount training datasets are constructed according to the characteristics of the NMR logging signal and noise, which is used to train the network. Secondly, the useful features of the NMR logging signals are learned by the network during training processing, in which the residual learning mechanism is employed to improve the training efficiency and the denoising performance. As a result, the Dn-ResNet may realize adaptive denoising without manual filter parameters tuning, prior knowledge of NMR logging signals and preprocessing of the original noisy signals. The performance of the proposed denoising network is demonstrated on both the synthetic NMR logging signals and field data. The effective signals are obtained from the noisy signals at different SNRs. In addition, an attempt to use the well-trained Dn-ResNet to deal with a single record provides similar results compared to 200 stacks. It shows that the number of stacks may be reduced to shorten the measurement time and improve the measurement efficiency. The results show the effectiveness and robustness of the proposed approach, which enables the technology of deep learning to be developed in application of NMR logging data processing.

Transformations of Pd/(N-Heterocyclic Carbene) Molecular Complexes into a Nanosized Catalytic Systems in the Mizoroki–Heck Reaction

The mechanism of the formation of catalytic species in the practically important Mizoroki–Heck reaction, which is in demand in modern fine organic synthesis, has been studied. It has been shown that catalysts based on palladium complexes with N-heterocyclic carbene ligands are transformed into a “ligand-free” form under the conditions of the Mizoroki–Heck reaction. Molecular modeling performed using quantum chemical methods showed that these processes compete with the target reaction at three of the six stages of the catalytic cycle. The presence of catalyst transformation products in the reaction system was confirmed by methods of nuclear magnetic resonance and mass spectrometry. Important mechanistic data have been obtained for the rational design of catalytic systems for cross-coupling reactions.

Summary of research methods for porosity and permeability of coalbed methane reservoir

In order to serve the research on the physical properties of coalbed methane reservoirs and improve the prediction effect of porosity and permeability of coal reservoirs, this paper, based on a large number of literature research, summarizes the concepts, influencing factors and prediction methods of coal seam porosity and permeability. The research shows that the main factors affecting the porosity of coalbed methane reservoir are coal petrographic composition, metamorphic degree, coal body structure and buried depth, compaction, tectonism, etc; The main influencing factors of permeability include component content, coal rank, coal body structure and in-situ stress, buried depth of coal seam, natural fracture of coal seam, matrix shrinkage, Klinkenberg effect, etc. The porosity prediction of coalbed methane reservoir generally adopts true and apparent relative density method, in addition, there are multiple regression method based on logging information, nuclear magnetic resonance logging method, etc; The measurement methods of CBM reservoir permeability mainly include the calculation method based on conventional logging, triaxial stress experimental research method, joint prediction method of nuclear magnetic resonance and electrical imaging logging, dynamic data analysis method and numerical simulation method. The development of coal seam porosity and permeability prediction technology needs innovative breakthroughs in hardware and software.

SYNTHESIS AND ANTIRADICAL ACTIVITY OF CONJUGATES OF URACIL DERIVATIVES WITH AMINO ACIDS

Two synthesis schemes for obtaining new derivatives of 5-hydroxy-1,3,6-trimethyluracil with fragments of protected natural amino acids are proposed. Synthesis includes two ways of obtaining products – chlorohydride, consisting of the protection of amino acids with phthalic acid and further production of chlorohydrides with their subsequent condensation in methylene chloride with uracil derivative, as well as carbodiimide, with tert-butoxycarbonyl protection of amino acids by amino group, also carried out in methylene chloride in the presence of a water-removing agent N,N’-dicyclohexylcarbodiimide. Both methods of placing protective groups in amino acid molecules are described. New compounds were obtained with yields of 65-98%. Also, by the method of N-alkylation with ethylene chlorohydrin, a linker was introduced into the 6-methyluracil molecule with subsequent separation of N1- and N3-derivatives. The reaction was optimized, and the ratio of reagents was revealed, at which the highest yield of the product alkylated at the N3- position is achieved. Successful attempts to attach amino acid fragments to the resulting N3-(2-hydroxyethyl)-6-methyluracil during boiling in ethyl alcohol are described. Due to the high biological activity of all the starting substances, the authors predicted the presence of possible reaction products. The article presents the results of studies of the antiradical (antioxidant) activity of 6-methyluracil derivatives based on the inhibition of the free radical 2,2-diphenylpicrylhydrazine by solutions of specified compounds with different concentrations. It was found that the synthesized conjugates, in particular N3-(2-hydroxyethyl)-6-methyluracil with the amino acid methionine attached via a linker, have increased values of the specified activity in comparison with the initial 6-methyluracil, which makes it possible for their further study. The newly obtained compounds were characterized by the methods of 1H and 13C nuclear magnetic resonance. For citation: Khazimullina Yu.Z., Gimadieva A.R. Synthesis and antiradical activity of conjugates of uracil derivatives with amino acids. ChemChemTech [Izv. Vyssh. Uchebn. Zaved. Khim. Khim. Tekhnol.]. 2023. V. 66. N 2. P. 36-44. DOI: 10.6060/ivkkt.20236602.6652.

Protein Cage Relaxivity Measurement for Magnetic Resonance Imaging Contrast Agents.

Contrast agents are employed to enhance the differentiation of diseased cells or lesions from normal tissues in magnetic resonance imaging (MRI). Protein cages have been explored as templates to synthesize superparamagnetic MRI contrast agents for decades. The biological origin imparts natural precision in forming confined nano-sized reaction vessels. With natural capacity to bind divalent metal ions, ferritin protein cages have been used for the synthesis of nanoparticles containing MRI contrast agents inside their core. Furthermore, ferritin is known to bind transferrin receptor 1 (TfR1) which is overexpressed on specific cancer cell types and could be used for targeted cellular imaging. In addition to iron, other metal ions such as manganese and gadolinium have been encapsulated within the core of ferritin cages. To compare the magnetic properties of ferritin loaded with contrast agents, a protocol for calculating the contrast enhancement power of protein nanocage is required. The contrast enhancement power is demonstrated as relaxivity and can be measured using MRI and solution nuclear magnetic resonance (NMR) methods. In this chapter, we present methods for measuring and calculating the relaxivity of ferritin nanocagesloaded with paramagnetic ions in solution (in tube) with NMR and MRI.

Перспективные методы магнитно-резонансной тераностики

The combination of high-resolution and high-sensitivity diagnostic methods with the therapy of socially significant diseases under the influence of various physical fields, methods or substances is the basis of new intensively developed areas of modern medicine. This review article analyzes advanced methods of magnetic resonance (MR) theranostics, such as MRI-guided laser therapy, MRI tracking in stem cell therapy, MRguided therapy using MRI-theranostic agents based on magnetic nanoparticles, transcranial magnetic stimulation combined with functional MRI (TMS/fMRI). The paper presents both research materials and examples of clinical applications of these methods.

Separation of flavonoids with significant biological activity from Acacia mearnsii leaves.

Acacia mearnsii leaves, which are a rich source of flavonoids, were used to separate and purify myricitrin (W3) and myricetin-3-O-glucoside (W1). Further, the antioxidant and hypoglycemic activities of the two purified flavonoids were evaluated. The flavonoids were separated using solvent partition, macroporous adsorbent resin column, and Sephadex column chromatography, and purified using preparative reverse-phase high-performance liquid chromatography (HPLC). The purified flavonoids were characterized using HPLC, mass spectrometry, and nuclear magnetic resonance methods. A high yield (7.3 mg g-1 of crude extract) of W3 was obtained, with a high purity of 98.4%. Furthermore, the purity of W1 was over 95%. W1 and W3 showed strong antioxidant activity and significantly inhibited α-glucosidase. W3 also demonstrated substantial α-amylase inhibitory capacity. This study indicated that A. mearnsii leaves, which are discarded in significant amounts, can be used as a source of myricitrin, thus providing more adequate material for the production of antioxidants and type II diabetes inhibitors. Hence, A. mearnsii leaves have the potential to create great market economic value and environmental benefits.

ODMR active bright sintered detonation nanodiamonds obtained without irradiation

We present the results of study the structure and composition of microcrystalline diamonds obtained by high-pressure high temperature sintering of detonation nanodiamond particles. Using optical detected magnetic resonance method, photoluminescence spectroscopy and Raman spectroscopy we found sintering of detonation nanodiamond significantly differ from initial detonation nanodiamonds and can be compared to high quality diamonds. Monocrystals of diamonds obtained by the method of oriented attachment have dimensions of up to tens of microns, possess the habitus of high-quality diamonds, and do not contain metal catalysts in the lattice structure. In those crystals, the presence of optically active nitrogen impurities in the crystal lattice is observed. In particular, there is a bright nitrogen-vacancy defects. They are characterized by optical detected magnetic resonance method, which shows that spin properties of the obtained single crystals correspond to high-quality natural diamonds and surpass synthetic diamonds obtained from graphite in the presence of metal catalysts, followed by irradiation and annealing to obtain nitrogen-vacancy defects optical defects in the diamond lattice. The presence of nitrogen-vacancy defects defects and the high-quality of the crystal structure of sintering of detonation nanodiamond allows us to consider them as potential candidates in quantum magnetometry. For this purpose, the possibility of a simple way to improve the AFM probe by fixing a microcrystalline sintering of detonation nanodiamond particle on its tip is demonstrated. Keywords: detonation nanodiamond, HPHT sintering, ODMR, single crystalline, photoluminescence, defects.

Experimental Investigation on the Imbibition Behavior of Nanofluids in the Tight Oil and Gas Reservoir through the Application of Nuclear Magnetic Resonance Method

Tight oil and gas resources are widely distributed and play an important role in the petroleum industry. Due to its nanoscale pore-throat characteristics, the capillary effect is remarkable, and spontaneous imbibition is very beneficial to the development of low-permeability reservoirs. In this study, the imbibition experiments of 2D nano blackcard, nanoemulsion, and water were carried out, respectively. The pore-throat fluid distribution characteristics before and after core imbibition were analyzed with nuclear magnetic resonance technology, and the enhanced oil recovery effects of 2D nano blackcard nanoemulsion, and water were comprehensively evaluated. The results show that the final recovery factors of cores soaked in 2D nano blackcard (0.005 ωt%) and nanoemulsion (0.02 ωt%) or imbibed in water are 32.29%, 26.05%, and 7.19%, respectively. It can be found that 2D nano blackcard is the fluid with the best imbibition effect. In this work, a new type of 2D nano blackcard was proposed and identified as a functional imbibition fluid for enhanced oil recovery in tight reservoirs, providing a practical reference for the effective development of tight, low-permeability oil and gas reservoirs.

Nontargeted metabolomics integrated with 1 H NMR and LC-Q-TOF-MS/MS methods to depict a more comprehensive metabolic profile in response to chrysosplenetin and artemisinin co-treatment against artemisinin-sensitive and -resistant Plasmodium berghei K173.

Our previous work revealed mutual and specific metabolites/pathways in artemisinin-sensitive and -resistant Plasmodium berghei K173-infected mice. In this study, we further investigated whether chrysosplenetin, a candidate chemical to prevent artemisinin resistance, can regulate these metabolites/pathways by integrating nontargeted metabolomics with 1 H NMR and LC-Q-TOF-MS/MS spectrum. The nuclear magnetic resonance method generated specifically altered metabolites in response to co-treatment with chrysosplenetin, including: the products of glycolysis such as glucose, pyruvate, lactate and alanine; taurine, closely associated with liver injury; arginine and proline as essential amino acids for parasites; TMAO, a biomarker for dysbacteriosis and renal function; and tyrosine, which is used to generate levodopa and dopamine and may improve the torpor state of mice. Importantly, we noticed that chrysosplenetin might depress the activated glycolysis induced by sensitive parasites, but oppositely promoted the inhibited glycolysis to generate more lactate, which suppresses the proliferation of resistant parasites. Moreover, chrysosplentin possibly disturbs the heme biosynthetic pathway in mitochondria. The MS method yielded changed coenzyme A, phosphatidylcholine and ceramides, closely related to mitochondria β-oxidation, cell proliferation, differentiation and apoptosis. These two means shared no overlapped metabolites and formed a more broader metabolic map to study the potential mechanisms of chrysosplenetin as a promising artemisinin resistance inhibitor.

Enzymatic Conversion of Hydrolysis Lignin—A Potential Biorefinery Approach

Lignin is an abundant and renewable source capable of replacing different raw materials in the chemical industry. It can be obtained from lignocellulosic biomass (LCB) via different pretreatment methods. In the present study, hydrolysis lignin (HL) from the SunburstTM pretreatment technology was utilized to investigate its enzymatic conversion. At first, soluble HL fractions were obtained via alkali solubilization followed by acid precipitation, referred to as acid precipitated lignin (APL). Furthermore, the APL was tested with three different bacterial laccases to identify the optimal conditions for its conversion into small molecular weight fractions. Among the tested laccases, Streptomyces coelicolor A3(2) (ScLac) displayed the highest rate of APL conversion with a high lignin dosage and under extremely alkaline conditions, i.e., 50 g/L in 0.25 M NaOH solution, resulting in higher molecular weight fractions. The increase in the molecular weight and quantitative linkages before and after the enzymatic oxidation of the APL were characterized by size exclusion chromatography (SEC), Fourier-transform infrared spectroscopy (FT-IR), and two-dimensional heteronuclear single quantum correlation nuclear magnetic resonance (2D HSQC NMR) methods.

Experimental Study on Fractal Characteristics of Adsorption Pore Structure of Coal

The adsorption pore structure is the key affecting the technology of enhanced coal bed methane recovery (ECBM). In this paper, nitrogen adsorption measurement (NAM) and low-field nuclear magnetic resonance (NMR) methods are used to test the structural parameters of adsorption pores of four coal samples with different metamorphic degrees. Combining with the fractal theory, the applicability and the physical significance of fractal dimensions obtained from different models are analyzed. Finally, the main factors affecting the complexity of the pore size structure and the influence of fractal characteristics on the adsorption properties of coal are discussed. The results show that with the increase in the degree of metamorphism, the ranking order of the volume and the specific surface area of adsorption pores of four coal samples are long flame coal > anthracite > gas coal > coking coal. The fractal dimension D2 calculated by the Frenkel–Halsey–Hill (FHH) fractal model ranges from 2.5 to 2.9, representing the degree of the pore surface irregularity, and D3 calculated by the FHH fractal model ranges from 2.004 to 2.037, representing the complexity of pore size distribution. There is no clear quantitative relationship between the fractal dimension and the single structure parameters of adsorption pores. The more the pore diameter distribution is concentrated in the range of 2–5 nm, the larger the fractal dimension is, the higher the complexity of adsorption pore structure is; D2, which represents the irregularity of the surface of coal, has a good linear positive correlation with the maximum adsorption capacity of N2.

Tactics of Surgical Treatment of Slipped Capital Femoral Epiphysis Associated With Mild Chronic Epiphyseal Displacement

Background. The appearing of data on cam-type FAI in patients with sequelae of slipped capital femoral epiphysis characterized by mild chronic epiphyseal displacement suggests that along with fixation of the proximal femoral epiphysis, modeling of the head-neck transition and restoration of the femoral offsets using arthroscopic techniques should be performed. Meanwhile, it is well known that after epiphyseal fixation, complete remodeling of the epimetaphysis and, consequently, disappearance of the morphological substrate of potential FAI can occur due to the ongoing enchondral and echondral growth. In this regard, the issue of indications for intraarticular interventions in studied patients remains currently open. The aim of the study was to determine the incidence of FAI in the postoperative period in patients with slipped capital femoral epiphysis characterized by mild chronic epiphyseal displacement, and to estimate the requirement of further surgical treatment. Methods. The results of the examination of 32 patients with mild chronic epiphyseal displacement in the typical posterior inferior direction who underwent cannulated epiphyseal screw fixation were analyzed for the severity of epimetaphysis remodeling and the presence of FAI in the postoperative period. Clinical, radiological, magnetic resonance, and statistical methods were used. Results. At the age of 18-19 years, FAI with pain syndrome in everyday life was found in 9 (28.1%) patients 8 of them did not have even partial remodeling of the femoral component of the joint, another 9 (28.1%) patients did not suffer from pain syndrome in everyday life, but had other clinical, radiological and MR signs of cam-type FAI. Complete or almost complete remodeling of the proximal femoral epimetaphysis occurred in 14 (43.8%) patients. Conclusion. In our opinion, therapeutic and diagnostic arthroscopy of the hip joint for the purpose of modeling the head-neck transition at the age of 18-19 years is indicated for more than one quarter (28.1%) of the investigated patients because of the presence of reliable signs of FAI.