Background. Primary brain tumor lesions include gliomas, which, according to epidemiological data, make up about 30% of all tumors of the central nervous system and are the most common. Overall and relapse-free survival rates depend on the degree of glioma malignancy and the histopathological nature of the detected lesion. For better treatment and prognosis, it is necessary to determine the exact location and histopathological nature of the tumor. Magnetic resonance imaging (MRI) remains the method of choice for structural brain assessment, but even with the use of contrast enhancement (CE), it does not always allow for reliable differentiation between tumor progression and post-therapeutic changes (radionecrosis, postoperative scars, cysts, inflammation) in patients after antitumor treatment. Radiopharmaceuticals, in particular ¹¹C-L-methionine, provide an assessment of tumor amino acid metabolism and complement structural data, increasing diagnostic accuracy. MRI, positron emission tomography and computed tomography (PET-CT) with ¹¹C-L-methionine in combination with morphological examination of the sample after stereotactic biopsy have shown high efficiency in the diagnosis of gliomas with varying degrees of malignancy.

Objective: to study the possibilities of applying PET-CT with ¹¹C-L-methionine in the diagnosis of continued growth and recurrence of glial tumors, as well as to conduct differential diagnostics with postoperative non-neoplastic changes.

Material and methods. A retrospective, descriptive, analytical study was conducted in the Department of Radionuclide Therapy and Diagnostics of the Saint Petersburg Clinical Scientific and Practical Center for Specialized Types of Medical Care (Oncological) named after N.P. Napalkov. It included 67 patients (34 men and 33 women aged 17 to 75 years, mean age was 43.5±15.6 years) for whom PET-CT was carried out in the period from 2007 to 2015 after neurosurgical treatment with suspected continued growth of glial tumors. All patients underwent CE-MRI and CE-CT. Correlation coefficient (r) was used to estimate the level of dependence between PET-CT data.

Results. In 55% of the cases, continued growth of high-grade gliomas (Grades IV and III) was detected. In these patients, the radiopharmaceutical accumulation index ranged from 1.3 to 5.1, with mean value 2.9±0.85. In patients with continued growth of benign astrocytomas, the degree of ¹¹C-L-methionine accumulation varied with mean value 1.6±0.51. The sensitivity and specificity of PET-CT in detecting brain glioma progression were 92.3% and 73.3%, respectively. The combination of CE-MRI and PET-CT provided a sensitivity of 96.1% in diagnosing glioma tumor progression. The results show that MRI and PET-CT data are consistent in 45 of 48 cases (92.8%) of proven glioma progression. An accumulation index greater than 2 can predict continuous growth of malignant glioma with 95% accuracy, and the threshold for differentiating benign glioma from inflammatory lesions is 0.9.

Conclusion. Although PET-CT has good sensitivity in differentiating postoperative lesions in patients with glioma, CE-MRI is necessary for localized and earlier diagnosis. The lack of visualization of avascular gliomas is one of the limitations of PET-CT, although CE-MRI does not exclude them.

Background. The results of radiological examinations largely determine the subsequent treatment strategy. Errors occur in 20–40% of cases and can have serious negative consequences for patients. It is crucial to understand the causes of these errors, which may impact the possibility of reducing their incidence. Objective: to identify the main risk factors for interpretative errors in radiology when analyzing radiation studies.

Material and methods. A retrospective analysis of 89 imaging studies with interpretative errors was conducted. The largest share had computed tomography (73%), followed by magnetic resonance imaging (15.7%), and radiography (11.3%). Errors were classified by prognostic factors from Category 1 (minimal changes) to Category 5 (critical). The time from initial examination to erroneous conclusions ranged from 0 to 2162 days, with an average of 80.6 days.

Results. The most common errors were detected in studies of brain (33.7%), chest (24.7%), and abdomen (15.7%). Incorrect interpretations included neoplastic lesions (39.3%), inflammatory changes (28.1%), and vascular pathology (22.5%). The most frequently observed errors were those with prognostic Category 4, requiring changes in treatment tactics (69.7%). A number of risk factors for the occurrence of interpretative errors were identified: the leading one was “incomplete analysis of semiotic features” (42.7%), followed by “anamnesis” (19.1%) and “insufficient knowledge” (12.4%). However, in 18% of cases, no risk factors were identified.

Conclusion. Identification of risk factors for the occurrence of diagnostic errors in the analysis of radiological studies is necessary for the subsequent development of preventive measures that should reduce the incidence of interpretative errors and improve the quality of radiological diagnostics in general.

Objective: to study the possibilities of radiological method in differential diagnosis of pulmonary tuberculosis in children.

Material and methods. The study included 75 children, who were examined for suspected tuberculosis due to detection of pathological lung changes on radiological images in the absence of complaints and clinical picture of the disease in the period from 2016 to 2024. The ultrasound diagnostic method was used to check for the presence of an interstitial lung reaction.

Results. On radiograms and computed tomograms, foci, consolidation, various signs of changes in lung interstitial tissue were determined. In 97.3% of cases, the tuberculous etiology of the detected changes on radiological images was excluded. It is advisable to call such findings “reactive changes in lung tissue”. In case of etiology verification, the conclusion “reactive changes in lung tissue” is replaced by a specific diagnosis. These changes are detected with a high frequency during the period of seasonal acute respiratory viral infections. The mean duration of reactive lung changes in nonspecific inflammatory processes is 4±2 weeks. The diagnostic period may change in case of protracted or chronic processes of non-tuberculous etiology.

Conclusion. There are no specific radiographic differences between reactive changes of any etiology and the tuberculous inflammatory process. Comparative assessment of radiographic images over a period of 2 to 6 weeks allows excluding a short-term nonspecific inflammatory process, thereby reducing the range of differential diagnostics. A process that lasts more than 6 weeks requires either justification of the cause, which should be reflected in the radiographic protocol, or introduction of alternative diagnostic methods with determination of the cause of the disease protraction. Both cases imply a completely different approach to patient management tactics. A radiographic picture of lung changes, which remains without image dynamics for more than 6 weeks, with a significant degree of probability, should be assessed as a process that is either inactive, or post-inflammatory, or tuberculous. Radiological signs of such changes may be similar, but patient management tactics are different.

The publication was prepared for the 130^th anniversary of the specialty and is intended to recall the contribution of pioneers to the development of modern radiation diagnostics. Moisey Isaakovich Goldstein (1894–1974) was a Doctor of Medical Sciences, Professor, organizer of the first Department of Roentgenology and Radiology in Kazan, and founder of the Kazan School of Radiologists. This article provides a comprehensive analysis of his role in improving radiological diagnostics and radiotherapeutic approaches in Russia during the 20^th century. Based on archival documents, biographical sketches, publications by M.I. Goldstein, colleagues’ recollections, and official republican and federal sources, the key stages of the scientist’s professional formation are examined: from epidemiological work in Chistopol in the early post-revolutionary years to the establishment of the first X-ray office and the introduction of radiotherapeutic methods in obstetric-gynecological and dermatological practice. His pedagogical legacy is demonstrated: the formation of the educational process, engagement of students in research work, supervision of candidate and doctoral dissertations, and mentoring a number of leading radiologists. Special attention is payed to the establishment of the Department of Roentgenology and Radiology at the Kazan Medical Institute in 1953 and the creation of the Kazan School of Radiologists, as well as to the significance of M.I. Goldstein’s work for the subsequent development of this direction. The main factors ensuring continuity and stability of the tradition are identified: a systematic approach to training, introduction of innovations in diagnostics and therapy, and attention to radiobiological aspects. The obtained results underscore the historical value of Professor Goldstein’s scientific activities and his role in shaping domestic radiology.