Characteristic Radiological Signs Research Articles

The Shrinking Lung Syndrome or Retracted Lung Syndrome During Systemic Lupus Erythematosus: About Two Cases

The shrinking lung syndrome represents an uncommon complication associated with systemic autoimmune diseases, primarily systemic lupus ery the matosus, but also Sjögren's syndrome and polymyositis. It is a condition that should be considered in any patient with an autoimmune disease presenting unexplained dyspnea. This syndrome is characterized by reduced lung volumes, elevation of the diaphragm, and restrictive physiology without significant parenchymal involvement. The article emphasizes the crucial role of thoracic CT in the diagnosis of the shrinking lung syndrome. Thoracic CT plays an essential role in identifying characteristic radiological signs such as pulmonary atelectasis and elevation of the diaphragmatic domes. These specific radiological features significantly contribute to confirming the diagnosis by excluding other potential causes of dyspnea, notably pulmonary embolism.

Possibilities of Computer Tomography in Preoperative Diagnosis and Surgical Treatment Planning of Juvenile Angiofibroma of the Nasopharynx and Skull Base

The purpose of work was to determine CECT characteristics of primary juvenile angiofibroma of the nasopharynx and skull base (JNA), as well as determination of the paths of spread for the tumor, search for those of them, which are statistically significantly associated with surgical blood loss of subsequent treatment and search for ways to model possible blood loss on their basis.Materials and methods. The data of 60 patients aged from 8 to 17 years were analyzed retrospectively. All patients were boys. The median age was 14 years. The median duration of the disease at the time of surgery was 7 months. The correlation between each of 45 evaluation criteria and intraoperative blood loss was determined for patients in the study group.Results. CT characteristics of JNA were established. The factors, detected by CECT, statistically significantly influencing intraoperative blood loss in angiofibroma treatment were established. A method for modeling intraoperative blood loss based on imaging data was presented.Conclusion. CT with contrast enhancement allows determining of characteristic radiological signs of JNA as well as its characteristics influencing blood loss during surgical treatment. Based on CT data it is possible to model blood loss potential during the JNA treatment.

Breast calcifications. Literature review

Breast cancer continues to maintain a leading position in the structure of the incidence of all oncological diseases among women. Early diagnosis of the disease at the stage of assessing indirect signs makes it possible in the future to maintain a good quality of life for patients by forming proper dynamic monitoring and performing functionally sparing surgical treatment. Interest in the early detection of benign and malignant pathology of the mammary gland is growing every year. A multidisciplinary approach to the study of the formation of breast calcifications makes it possible to look at the problem in a multifaceted way, and ways to solve problems in the process of diagnosis underlie the biochemical understanding of the mechanisms of formation, which is no less important when evaluating mammographic images. Practically up to 50 % of non-palpable breast tumors in practice are detected by signs of existing calcifications in the gland tissue. At present, the problem of early detection of malignant tumors of the breast by radiographic signs of these calcifications, their shape and nature of location in the gland tissue and their further pathomorphological confirmation is being actively studied.We have analyzed the literature data of foreign and domestic authors over the past 20 years. The problem was considered from the mechanism of formation and morphological features of calcifications in the breast tissue to their radiographic assessment on mammographic images. According to the results of the studied literature, the biochemical features of the formations were taken as the basis for understanding the nature of calcifications in the breast tissue. On a biochemical level, calcifications are usually classified into two main types: type I, consisting of calcium oxalate, and type II, consisting of hydroxyapatite. The classification is based on chemical composition and mammographic characteristics, including morphology, distribution and density. Speaking about calcium oxalate, the benign nature of education is most often implied, which cannot be said about hydroxyapatite. Mammography is the main method for diagnosing these formations, taking into account the characteristics of the characteristic radiological signs, which are also detailed in this article.Understanding the molecular and structural development of calcifications may aid in the detection and treatment of breast lesions. Identification of these structures in a patient diagnosed with breast cancer refers to the early diagnosis of the disease, where, with timely prescribed therapy, we get high chances of good long-term results of relapse-free survival.

Rare Case of a Dyggve-Melchior-Clausen Syndrome Revealed by a Spinal Cord Compression

Dyggve-Melchior-Clausen syndrome (DMSC) is an rare autosomal recessive skeletal disorder that belongs to the category of spondyloepiphyseal dysplasia. The present work reports a case of DMCS in a nine- year-old kid who was admitted for spinal cord compression accompanied by mental retardation and dysmorphic syndrome. The patient had shown a C1-C2 dislocation with compression of the bulbo-medullary junction, platyspondyly with double ondulation of all the vertebral endplates, widely open acetabulums and epi- metaphyseal dysplasia of the femoral heads. Discussion: The syndrome is clinically characterized by a staturo- ponderal delay of varying severity. Radiological characteristics consist of a scalloped appearance of the iliac wings, spondyloepimetaphyseal dysplasia and platyspondyly. The diagnosis of Dyggve-Melchior-Clausen syndrome can be suspected after a clinical evaluation, a detailed patient history, and identification of characteristic clinical and radiological signs.

Huge lymphangiomatous mesenteric cyst- A case report

Mesenteric cysts are rare intra-abdominal lesions. The lack of characteristic clinical features and radiological signs may present great diagnostic difficulties. Lymphangiomas can originate in any organ with less than 5% occurring in the abdominal cavity. They can occur anywhere in the small bowel or colonic mesentery. Here we present a 58-years-old female with abdominal discomfort, mild pain and abdominal fullness for four months. Radiologically, left adnexal neoplasm was suggested. Laparotomy was performed and left colon segment with huge mesenteric mass was found and resected. Confirmation of diagnosis as lymphangiomatous mesenteric cyst was done on histopathology.

The significance of morphological verification of calcifications in differential diagnsis of the mammary gland pathology

Relevance of the research. An important advantage of radiological imaging methods is their ability to detect areas of calcification in tissues, even in the form of microcalcifications, measuring up to 1 mm. These microcalcifications are formed under the influence of various factors and serve as important diagnostic criteria for a number of pathologies. Microcalcifications, detected during mammographic examination, are considered reliable markers of breast cancer. The classification of breast microcalcifications is based on their radiological and histological characteristics, which are evaluated during the diagnostic process to identify breast pathology. The aim of the study is to determine the frequency of detecting calcifications in the breast through mammographic examination and verify their significance as diagnostic criteria for breast cancer.Materials and methods. The study utilized a processed randomized sample of anonymized archival mammograms from 100 women of mature and elderly age who underwent screening or preventive examinations at the mammography room of the CNE "6th city polyclinic of Lviv". The examinations were conducted using the Fujifilm Amulet Innоvality machine (Japan) in the craniocaudal (CC) and mediolateral oblique (MLO) projections. Histological slides from the archives of the Histology, Cytology, and Embryology Department of Danylo Halytsky Lviv National Medical University and anonymized archival preparations of DOBRA DIAGNOSTYKA LLC were used for the study.The slides were examined under a UlabXSP-137TLED microscope at various magnifications and photographed using an XCAM 1080P camera.Results. It has been established that the frequency of detecting calcifications during screening/preventive examinations of mature and elderly women was 69% of the total number of subjects examined, more than half of them bilaterally. The detected calcifications had different localization, shape, size, and quantity. The analysis of scientific literature sources indicates the existence of different views on the presence of calcifications in breast tissue - some authors consider them to be a characteristic radiological sign of the breast, while others assert that the frequency of malignant neoplasms increases, including in cases of calcification of the glandular tissue. The results of mammary glands histological studying in mature and elderly women indicate that calcifications can be visualized in the context of age-related changes in the stroma or parenchyma of the organ, which don`t exhibit morphological signs of neoplastic development. These calcifications can be manifestations of age-related involution and are possibly formed as a result of calcification of blocked secretions. Conclusion. The presence of calcifications can`t be considered a definitive diagnostic criterion for breast cancer. The final verification of the diagnosis can only be made after conducting a histological examination.

Rigler Triad in Gallstone Ileus: Case Report and Literature Review

Gallstone ileus is an uncommon complication of calculous cholecystitis, which can lead to a gastro-intestinal obstruction. A non-specific clinical presentation is frequent. Imaging studies can present characteristic radiological signs. We present a 56-year-old female patient with constipation for the past 72 hours, colicky intermittent abdominal pain and vomiting.

Infections Mimicking Malignancy in Kano, Nigeria: A Teaching Hospital Experience

Objective: This study aimed to evaluate the pattern of presentation of infectious lesions mimicking malignancy. This will serve to heighten clinical indices of suspicion and prevent unwarranted aggressive management.
 Methods: This is a 19-year (1999-2017) audit review of all morphologically diagnosed infection-related lesions in which malignancy was primarily clinically suspected.
 Results: Fifty-six cases of infection-related mimics of malignancy were diagnosed in the study period: schistosomiasis related, 22 (39.2%); actinomycosis, 21(37.5%); tuberculosis-related, 10 (17.9%); fungi-related, 3(5.4%). Twenty-one cases of actinomycosis of the lower limbs and oropharynx were mistaken for melanoma, squamous cell carcinoma, sarcoma, and oropharyngeal carcinoma. The mean age was 33±17years.The 10 patients with atypical Mycobacterium tuberculosis-mimicking malignancy had mean age of 37±14 years and included three in the testes, testicular cases, one from the jaw, and two cases each from ovary, breast, and uterus. Of the three fungal lesions, there was a case each from the brain, skin, and bone. All were males with mean age of 21±7 years.
 Conclusion: For accurate diagnosis of infection-related mimics of malignancy, a high index of clinical suspicion, knowledge of and attention to characteristic radiological signs, and obtaining representative tissues for histopathologic and cytopathologic diagnoses are paramount.

PULMONARY NODULES AND THE HALO SIGN: CAN WE THINK OF JUST ONE DIAGNOSIS?

TOPIC: Imaging TYPE: Medical Student/Resident Case Reports INTRODUCTION: The halo sign in computed tomography (CT) scan of the chest consists of ground-glass opacity around pulmonary lesions. It has been linked to a wide variety of pathological processes #1. CASE PRESENTATION: Male, 66 years old, admitted for hyperglycemia; he had no respiratory symptoms. At physical examination he presented with jaundice, choluria and acholia. The laparoscopic pancreatic biopsy confirmed the presence of pancreatic cancer. Chest-abdomen-pelvis CT scan were performed for staging, and identified numerous bilateral pulmonary nodules, infracentrimetic, with a circular area of ground-glass attenuation (halo sign), being hypothesized invasive pulmonar aspergillosis or metastatic lesions with associated bleeding, the last one being less likely because the primary lesion had hypovascular behavior. He was subsequently submitted to bronchofibroscopy, whose cytology of the bronchoalveolar lavage was negative for neoplastic cells, identifying the existence of fungal hyphae; the mycological examination was negative. The galactomannan survey was also negative. He repeated bronchofibroscopy in an attempt to identify the fungus, however, the result was also negative. It was decided to perform a transthoracic lung biopsy, which confirmed the presence of metastases. The patient died a few weeks later, due to systemic progression of the neoplasm. DISCUSSION: The halo sign was initially believed to be a specific sign of invasive pulmonary aspergillosis, but it has already been associated with multiple other pathologies, such as, inflammation, infection or cancer #2. CONCLUSIONS: In this case, it is highlighted the difficulty in establishing a definitive diagnosis and the importance of placing multiple hypotheses of diagnosis in the presence of some characteristic radiological signs, such as the halo sign, very suggestive of invasive pulmonary fungal infections in immunocompromised patients, but not specific. REFERENCE #1: Lee YR, Choi YW, Lee KJ, Jeon SC, Park CK, Heo JN. CT halo sign: the spectrum of pulmonary diseases. Br J Radiol 2005; 78:862–5 REFERENCE #2: Parrón M, Torres I, Pardo M, Morales C, Navarro M, Martínez-Schmizcraft M. Signo del halo en la tomografía computarizada de tórax: diagnóstico diferencial con correlación anatomopatológica [The halo sign in computed tomography images: differential diagnosis and correlation with pathology findings]. Arch Bronconeumol. 2008 Jul;44(7):386-92. Spanish. PMID: 18727892. DISCLOSURES: No relevant relationships by Mariana Argel, source=Web Response No relevant relationships by Marta Sousa, source=Web Response No relevant relationships by António Torres, source=Web Response

THREE CASES OF BOWEL OBSTRUCTION BY BROAD LIGAMENT HERNIA

Abstract INTRODUCTION Internal hernias caused by broad ligament defects are an infrequent cause of bowel obstruction. These defects may be congenital or acquired mainly by gynecological antecedents. Small bowel is the most common affected and the diagnosis is difficult due to nonspecific symptoms and absences of characteristic radiological signs. MATERIAL AND METHODS We report the cases of three women aged from 43 to 56 years old, who came to the emergency with abdominal pain, vomiting and bloating of hours duration. One patient has a history of laparoscopic appendectomy, the rest of them with no surgical history. In all of the cases, x-rays showed dilatation of small bowel loops and air-fluid levels and the abdominal TC revealed a generalized distention of bowel loops with transition point in the terminal ileum with no identifiable cause compatible with small bowel obstruction. RESULTS We decided to perform an urgent surgery with an exploratory laparotomy in one case and the rest by laparoscopic approach, finding an internal hernia occasioned by incarceration of small bowel through a broad ligament defect. In all cases, the hernia content was liberated without evidence of ischemia with no need for intestinal resection, and the defect was closed. All patients had a favourable postoperative course without complications. DISCUSSION Broad ligament defects are a rare cause of internal hernias. These are difficult to diagnose clinically as well as radiologically for an absence of characteristic signs. A high level of clinical suspicion allows early diagnosis and the treatment should be performed as soon as possible to reduce the chances of intestinal necrosis.

Radiologic findings that aid in the reduction of misdiagnoses of Langerhans cell histiocytosis of the bone: a retrospective study

BackgroundThis study aimed to identify the characteristic radiological signs for the diagnosis of Langerhans cell histiocytosis (LCH) of the bone.MethodsWe retrospectively studied 82 cases of LCH with bone lesions confirmed by pathology. Clinical and radiological features of the patients were analyzed.ResultsA total of 64 and 18 patients had single and multiple bone lesions, respectively. With regard to LCH with single bone lesions, 37.5% (24/64) of lesions were located in the skull and presented as bone destruction with or without soft tissue mass. The correct diagnosis rate of these lesions was 60.0% (9/15) in children and adolescents, but was only 22.2% (2/9) in adults.A total of 26.5% (17/64) of the solitary lesions were found in the spine. Of these, 88.2% (15/17) were located in the vertebral body and appeared to have different degrees of collapse, and 66.7% (10/15) of these lesions were correctly diagnosed.Of the unifocal lesions, 21.8% (14/64) were located in other flat and irregular bones and manifested as osteolysis. Only 21.4% (3/14) of these cases were correctly diagnosed.In total, 14.1% (9/64) of the isolated bone LCH lesions were located in the long bones. Of these, 77.8% (7/9) were located in the diaphysis and presented as central bone destruction with or without fusiform periosteal reaction and extensive peripheral edema, of which 42.9% (3/7) were correctly diagnosed before surgery or biopsy.With regard to LCH with multiple bony destructive lesions, 71.4% (10/14) of cases in children and adolescents were correctly diagnosed; however, all four cases among adults were misdiagnosed.ConclusionIn all age groups, isolated diaphyseal destruction of the long bone with fusiform periosteal reaction and extensive peripheral edema, vertebra plana of the spine, and bevelled edge of skull defects accompanied by soft tissue masses strongly suggest LCH diagnosis. Moreover, the multiple bone osteolytic destruction in children and adolescents strongly suggests LCH diagnosis. Familiarity with these typical radiological signs of LCH is necessary to decrease misdiagnoses.

ASSOCIATION OF LEVELS OF PULMONARY FUNCTION WITH SELECTED DEMOGRAPHIC VARIABLES OF WORKERS OF SHIVA SPINNING MILL TAPA, PUNJAB

India is now a major power source and is turning into a developed country from a developing country. It is been estimated by the government of India that small-scale industries contribute 40% of the gross industrial value in Indian economy. A diagnosis of obliterative bronchiolitis induced by cotton dust exposure was established on the basis of the occupational history and the characteristic radiological signs. In this study Quantitative, explorative study was used to assess the effect of cotton dust exposure on pulmonary function among workers of cotton industry at selected industries. The main study was conducted in Shiva Spinning mill Tapa, Punjab. It can be concluded from the present study that, the exposure to cotton dust has significant association with the pulmonary function with selected demographic variables of workers of shiva spinning mill tapa, Punjab.

Acute mesenteric ischemia: A review of the main imaging techniques and signs

Acute mesenteric ischaemia is an abdominal emergency because reduced blood flow to bowel loops rapidly leads to irreversible necrosis and death.This paper reviews the different conditions (arterial, venous, low-flow states) that can result in reduced blood flow to bowel loops.Since the clinical and laboratory findings are nonspecific, imaging tests play an important role in the diagnosis of mesenteric ischaemia. Multidetector computed tomography is the first-choice technique for the initial workup in cases of suspected acute mesenteric ischaemia because it can rule out other causes of acute abdominal pain. It is important to know the characteristic radiological signs of this entity, because early diagnosis is essential to prevent progression to life-threatening intestinal necrosis.

The arch bridge sign: a newly described CT feature of the coronavirus disease-19 (COVID-19) pneumonia

To investigate the distribution of CT features and also to introduce a novel described CT feature of coronavirus disease-19 (COVID-19) pneumonia. A series of radiologic signs in 11 COVID-19 patients were summarized and made morphometric analysis. A special sign termed as "the arch bridge sign" owing to its morphological mimicking an arch bridge was firstly introduced. Statistical analyze showed that the subpleural area is the priority distribution location (14/14) and the sign inclined to perform in those patients in a relatively early stage (6/8) and with moderate clinical severity (8/8). Segment VI in lower lobe involved most (6/14). In this retrospective study, other characteristic radiologic signs of COVID-19 pneumonia were analyzed synchronously. A series of radiologic signs were identified in bilateral lungs with a bias towards segment VI, I + II and X. Segment VI had the largest number of each sign. Ground-glass opacities (GGOs), subpleural distribution pattern and vessels dilatation were the top three most common signs among them. The recognition of the arch bridge sign may benefit patient care by earlier definitive diagnosis of COVID-19 pneumonia. The lesions of COVID-19 pneumonia distributed mainly in the back-lung segments, which characteristic may light new ideas in clinical treatment and nursing strategy.

Silent Sinus Syndrome: Interesting Computed Tomography and Magnetic Resonance Imaging Findings.

Silent sinus syndrome (SSS) is the spontaneous unilateral collapse of the maxillary sinus and orbital floor with complete or partial opacification of the collapsed sinus. The key features in a patient who presents with SSS are painless progressive unilateral maxillary sinus disease in the absence of rhinosinusitis, trauma, or surgery. SSS is a rare disorder but could be under-diagnosed because of a lack of recognition. SSS is characterized by spontaneous and progressive enophthalmos (“sunken” eye-eye recession into the globe) and hypoglobus (globe displaced downward; and a drop in the pupillary level), so it is common for these patients to present first to an ophthalmologist. Although mostly observed in adults, there have been reports of SSS in children. SSS in younger individuals has characteristic clinical and radiologic signs with, in many cases, abnormal intranasal anatomic characteristics on the affected side. SSS should be differentiated from other causes of spontaneous enophthalmos, such as Parry-Romberg syndrome and linear scleroderma. The aim of this report was to alert the reader to the imaging findings in patients with SSS. This syndrome is well recognized by rhinologists and to a lesser extent to ophthalmologists but remains relatively unknown to general radiologists.

Temporal bone meningiomas: emphasizing radiologic signs to improve preoperative diagnosis.

Temporal bone meningioma is an extremely rare disease. Lack of clinical attention due to its rarity might lead to delayed diagnosis. This short communication aims to emphasize radiologic signs of temporal bone meningiomas to improve preoperative diagnosis. Radiological characteristics of temporal bone meningiomas are discussed. Temporal bone meningioma is characterized by diffuse "hairy" trabecular hyperostosis without the destruction of trabecular structures, bone thickening, and irregular surface margins of the temporal bone on computed tomography. The dural tail sign is a unique feature of temporal bone meningioma on magnetic resonance imaging. Otolaryngologists certainly should be aware of characteristic radiologic signs of temporal bone meningiomas. Using modern computed tomography and magnetic resonance imaging protocols enables with a high degree of accuracy to distinguish temporal bone meningiomas from other more common entities in this location.

Isquemia mesentérica aguda: Revisión de las principales técnicas y signos radiológicos

Acute mesenteric ischemia is an abdominal emergency because reduced blood flow to bowel loops rapidly leads to irreversible necrosis and death.This paper reviews the different conditions (arterial, venous, low-flow states) that can result in reduced blood flow to bowel loops.Since the clinical and laboratory findings are nonspecific, imaging tests play an important role in the diagnosis of mesenteric ischemia. Multidetector computed tomography is the first-choice technique for the initial workup in cases of suspected acute mesenteric ischemia because it can rule out other causes of acute abdominal pain. It is important to know the characteristic radiological signs of this entity, because early diagnosis is essential to prevent progression to life-threatening intestinal necrosis.

Intestinal perforation in necrotizing enterocolitis: Does cardiac surgery make a difference?

The aim of this study is to evaluate the patients with intestinal perforation secondary to necrotizing enterocolitis (NEC) following cardiac surgery in the terms of risk factors and diagnosis/treatment process. A series of cases operated for intestinal perforation secondary to NEC were retrospectively reviewed in two groups. Group I involved patients who had cardiac surgery for congenital heart disease previous to intestinal perforation secondary to NEC. Group II consisted patients who had intestinal perforation secondary to NEC without any previous cardiac surgery. Demographic characteristics, prenatal and postnatal features, and pre- and post-operative course of groups were statistically compared to define differences. Thirty-two patients underwent laparotomy secondary to intestinal perforation in this period. The gestational age and birth weight were smaller in Group II (p=0.001, p=0.001). Intrauterine growth retardation was more frequent in Group II (p=0.05). More Group I patients had hypotensive periods (p=0.018) before the diagnosis of NEC. Prostaglandin treatment and requirement of renal replacement therapy were more frequent in Group I (p=0.022, p=0.03). The mortality rate was higher in Group I (p=0.018). All patients in Group I were late stage NEC at the time of diagnosis. NEC developing after cardiac surgery is different from NEC seen in the neonatal period in the terms of etiology, facilitating factors, and clinical course. Mortality rate is higher in NEC after cardiac surgery. The diagnosis of intestinal perforation might be difficult in NEC after cardiac surgery due to insignificant physical examination findings and characteristic radiological signs of NEC. The history of prostaglandin usage and requirement of renal replacement were thought as alarming signs in terms of possible intestinal complications after cardiac surgery.

Psoriatic arthritis: pathogenetic features and innovative therapies

The paper considers the modern concepts of the etiology and pathogenesis of psoriatic arthritis (PsA). The latter is currently indicated as a T-cell-mediated disease that is based on the activation of cellular immunity, followed by the hyperproduction and imbalance of key pro- and anti-inflammatory cytokines, such as tumor necrosis factor-α (TNF- α), interleukin-1β (IL-1β), IL-6, IL-12/23, and IL-17. The paper presents the basic principles of diagnosis and clinical manifestations of the disease and notes the importance of screening questionnaires, the use of which allows specialists to diagnose PsA early, by actively identifying articular complaints, the characteristic clinical and radiological signs of damage to the joint, spine, and entheses. It is pointed out that the key target of pharmacotherapy for PsA is to achieve remission or minimal activity of the main clinical manifestations of the disease, to slow down or prevent its radiographic progression, to increase the length and quality of life in patients, and to reduce the risk of comorbidities. The authors characterize the major groups of used drugs: nonsteroidal anti-inflammatory drugs, conventional and targeted synthetic disease-modifying antirheumatic drugs, and biological drugs (inhibitors of TNF-α, IL-12/23, and IL-17). The key Treat-to-target principles of patient management are considered; it is noted that strict control over disease activity and treatment results provides suppression of all major clinical manifestations of PsA. The paper also shows the basic principles of the creation and further development of the All-Russian Registry of PsA patients, which makes it possible to optimize management decision-making on the provision of high-tech medical care and drugs for this cohort of patients.

OSTEONECROSIS OF THE KNEE

Spontaneous osteonecrosis of the knee (SONK) is the most common type of knee osteonecrosis. It causes subchondral bone damage and in the majority of cases leads to cartilage damage and secondary osteoarthritis. The etiology is commonly explained with two main theories, vascular and traumatic. Vascular theory is based on disrupture of bone blood supply which causes local ischaemia and subchondral bone necrosis. Traumatic theory suggests the development of subchondral insufficiency fractures due to mechanical overload, which causes local oedema, ischaemia and necrosis. SONK typically appears in middle age and older women, with acute onset of sharp pain in the medial femoral condyle without predisposing trauma. Considering that the characteristic radiological signs are not seen on conventional radiography until advanced stage, magnetic resonance imaging is the gold standard in diagnostics. Treatment depends on the size and stage of the osteonecrotic lesion. Small osteonecrotic lesions are usually successfully treated non-operatively, which is based primarily on protected weight bearing and physical therapy. Medium osteonecrotic lesions are treated either non-operatively or operatively, while large osteonecrotic lesions are almost always treated operatively. Most commonly used joint preserving procedures include arthroscopic bone marrow stimulation using microfracture technique, core decompression, osteochondral autologous or homologous transplantation, artificial graft transplantation, and medial opening-wedge high tibial osteotomy. The treatment of choice after subchondral bone collapse is knee arthroplasty.