The solitary lesion or "coin-shaped lesion" is a focal point< 3 см в диаметре, различимый на рентгенограмме легкого. Он обычно окружен легочной паренхимой.
2. How can a solitary lesion in the lung be represented?
Most often it is a neoplasm (cancer) or a manifestation of infection (granuloma), although it can represent a lung abscess, pulmonary infarction, arteriovenous anomaly, resolving pneumonia, pulmonary sequestration, hamartoma and other pathology. General rule is that the probability malignant tumor corresponds to the patient's age.
Thus, lung cancer is rare (although it does occur) in 30-year-olds, while 50-year-old smokers may have a 50-60% chance of having a malignant tumor.
3. How is a solitary lesion in the lung detected?
Usually, a solitary lesion is detected by chance during routine X-ray examination lung Several large studies have found that more than 75% of lesions were unexpected findings on plain radiographs of the lung. Symptoms indicating lung disease were observed in less than 25% of patients. Nowadays, solitary lesions are detected using other highly sensitive studies, such as CT.
4. How often is a solitary lesion in the lung a tumor metastasis?
In less than 10% of cases, solitary lesions represent tumor metastases, so there is no need for an extensive tumor search in organs other than the lungs.
5. Is it possible to obtain a tissue sample from the lesion using fluoroscopic or CT-guided needle biopsy?
Yes, but the result will not affect your treatment. If the biopsy reveals cancer cells, the lesion should be removed. If the biopsy is negative, the lesion still needs to be removed.
6. What is the importance of radiological findings?
They are not the most important. The resolution of modern CT machines allows for a better assessment of signs characteristic of cancer:
a) Fuzzy or unevenly jagged edges of the lesion.
b) The larger the lesion, the more likely it is to be malignant.
c) Calcification of the lesion usually indicates benign education. Specific central, diffuse or layered calcification is characteristic of granuloma, while denser calcifications in the form of irregularly shaped grains are observed in hamartoma. Eccentric or small speckled calcifications may be present in malignant lesions.
d) CT can examine changes in the relative density of lesions after contrast administration. This information increases the accuracy of diagnosis.
7. What social or clinical evidence suggests that the lesion is more likely to be malignant?
Unfortunately, there is no data that is sensitive or specific enough to influence diagnosis. How elderly age, and long-term smoking are factors that make lung cancer more likely. Winston Churchill had to get sick lung cancer, but did not get sick.
Therefore, information that the patient is the president of a speleological club (histoplasmosis), his sister raises pigeons (cryptococcosis), he grew up in the Ohio River Valley (histoplasmosis), works as a gravedigger in a dog cemetery (blistomycosis), or simply took a tourist trip to the San Valley - Joaquin (coccidioidomycosis), provide interesting supporting information, but do not affect diagnostic measures with a solitary focus in the lung.
8. What is the most important part of the medical history?
Old radiographs chest. If the lesion is recent, it is more likely to be malignant, and if it has not changed in the last 2 years, then it is less likely to be malignant. Unfortunately, even this rule is not absolute.
9. If a patient was previously treated for a malignant tumor, and now he has a solitary lesion in the lung, can it be said that this lesion is a metastasis?
No. The probability that a lesion in the lung is a metastasis is less than 50%, even if the patient previously had a malignant tumor. Thus, diagnostic measures for such a patient will be the same as for any other patient with a newly appeared solitary lesion in the lung.
10. How should one deal with a solitary lesion in the lung?
Complete information about travel and activities is interesting, but does not affect the progress of the diagnosis. Due to the peripheral location of most lesions, bronchoscopy has a success rate of less than 50%. Cytological examination sputum is not very informative, even if it is performed by the most good specialists. A CT scan is recommended as it can identify other potentially metastatic lesions and delineate the condition lymph nodes mediastinum.
As stated above, percutaneous needle biopsy is approximately 80% informative, but its result rarely influences subsequent management.
It is important to determine whether the patient can tolerate radical surgery. Function of the lungs, liver, kidneys and nervous system must be considered stable. If it is unlikely that the patient will live for several more years, then there is simply no point in removing an asymptomatic lesion in the lung.
The main way for a patient to undergo surgery is resection of the lesion for diagnostic purposes, performed using thoracoscopy, which has the least invasiveness, or a small thoracotomy.
11. What should be the scope of the operation if the lesion is a cancerous tumor?
Although some studies suggest that wedge resection is sufficient, removal of the anatomical lobe of the lung remains the procedure of choice. Cancer that is found as a solitary lesion is early stage with 65% 5-year survival rate (in the absence of visible metastases). Relapses are divided into local and distant.
Educational video of the anatomy of the roots and segments of the lungs
You can download this video and view it from another video hosting site on the page:When receiving images after an MRI of the brain, the patient examines them, despite the fact that he does not have the special knowledge to decipher the examination results. But even he becomes clear that there are some pathologies if he sees dots or spots white, standing out sharply against the general background. Let's find out what could be the causes of white spots on MRI images of the brain.
Perivascular spaces are fluid that accumulates along blood vessels, feeding the brain. Another name for them is criblures. Every person has them, but usually they are small and are not visualized on photographs of the organ being examined.
In case of violation cerebral circulation criblures expand. Because they are filled with cerebrospinal fluid. They contain a large number of hydrogen atoms. And in this area the response signal will be of high intensity, which can be seen in the photographs as a white spot.
Enlarged perivascular spaces are detected in many patients. Most often they are harmless. A neurologist can accurately determine whether criblures are dangerous in particular cases.
Demyelinating pathologies
Demyelination is pathological process, affecting the myelin sheath of nerve fibers. The nature of the damage depends on its cause. She may be:
- Congenital (hereditary predisposition to the disease).
- Acquired (demyelination develops as a result of inflammatory processes in the brain).
Here are the diseases that show demyelinating lesions in the brain on MRI:
- Myelinopathy;
- Leukoencephalopathy;
Typically, demyelinating lesions appear as multiple white spots. The patient may perceive them as criblures because they are similar. Only a specialist can distinguish them from each other based on the degree of severity and localization of the increased signal.
Gliosis in the medulla
Gliosis of the brain is the process of replacing neurons with glial cells. This is not an independent disease, but a consequence of other diseases.
Pathology in the form of foci of gliosis on MRI is usually detected in the following diseases:
- Encephalitis;
- Hypoxia of brain structures;
- Long-lasting hypertension;
- Tuberculosis and multiple sclerosis.
Glial cells perform the work that dead neurons were supposed to do. It is thanks to them that the functions of the nervous system are restored after injuries. Single small lesions can only be detected on MRI. There are usually no other symptoms. If the underlying disease continues to kill neurons, a clinical picture, and on the MRI images multiple pathological foci of the brain are already visible.
MRI helps detect the presence of gliosis, but in most cases does not tell what caused the changes. The differential diagnosis of dyscirculatory encephalopathy with multiple sclerosis. To decipher the results, you will need the help of at least two specialists with extensive experience: a neurologist and a neuroradiologist.
Brain swelling
White spots on an MRI may indicate swelling of the brain tissue. They develop against the background:
- injuries;
- ischemia;
- inflammation;
- hemorrhages.
At the initial stage of the disease, MRI reveals signs of perifocal edema in the form of light spots in the area of the affected area of the organ. If normal blood circulation is not restored, generalized edema develops. The brain swells. On an MRI, this is visible in a blurry picture in which the structures of the organ are not visible, since they all provide a high-intensity signal to the tomograph.
Sites of Alzheimer's disease
MRI can be used to diagnose and monitor the progress of Alzheimer's disease. Focal formations in this disease are not white, but almost black. This is due to atrophic processes occurring in the organ, which begins to decrease in size.
The affected areas do not respond well to the radio signal sent to them, so they are called low signal intensity areas. Dystrophy of the posterior parts of the brain is especially well visualized.
Magnetic resonance imaging reveals structural abnormalities in the brain. That's why this method The study is useful in diagnosing diseases that cause changes in the structure of the organ and the blood vessels that penetrate it. Anyone can distinguish an image of a healthy brain from an image with pathological foci. But only a doctor can make a diagnosis after a long study of the MRI results.
– a form of secondary tuberculosis that occurs with the formation of foci of specific inflammation in the lungs no more than 10 mm in diameter. It is asymptomatic or minimally symptomatic. In some patients focal tuberculosis lungs may be accompanied by malaise, low-grade fever, pain in the side, and dry cough. In the diagnosis of focal tuberculosis, the most informative are chest X-rays and detection of MBT in sputum or bronchial washings. IN initial period patients with focal pulmonary tuberculosis are prescribed a combination of three to four main anti-tuberculosis chemotherapy drugs, followed by a reduction to two names.
General information
Pathogenesis
In the pathogenesis of reactivation endogenous infection As the cause of focal pulmonary tuberculosis, the lymphohematogenous dispersion of mycobacteria throughout the body plays a decisive role. Focal pulmonary tuberculosis is predominantly localized in the upper lobe. Numerous studies in the field of phthisiology and pulmonology explain this various factors: limited mobility of the apex of the lung, its weak aeration, slow blood and lymph flow in this area, vertical position the human body and even hypersensitization, which promotes selective fixation of mycobacteria in the apex of the lungs.
Classification
Depending on the duration of the course, focal pulmonary tuberculosis can be fresh (soft-focal) and chronic (fibrous-focal).
- Fresh tuberculosis is initial stage a secondary process that developed in a patient who was previously infected with mycobacteria and recovered from the primary infection. Morphologically it is characterized by endobronchitis and peribronchitis in the area of segmental bronchi, and with the involvement of the alveoli - lobular bronchopneumonia.
- Chronic focal tuberculosis can develop both as a result of resorption of fresh focal tuberculosis, and as a result of other pulmonary forms - infiltrative, disseminated, cavernous. In this case, the inflammatory foci are encapsulated and replaced connective tissue or become calcified. In essence, they are residual fibrous foci, but under certain conditions they can be reactivated, causing an exacerbation of the tuberculosis process and an increase in the boundaries of the lesion. In turn, with progression, a chronic focal process can also transform into infiltrative, cavernous or disseminated pulmonary tuberculosis.
In its development, focal tuberculosis goes through the phases of infiltration, decay and compaction. Depending on the size, there are small (up to 3 mm in diameter), medium (up to 6 mm), large (up to 10 mm) lesions.
Symptoms of focal tuberculosis
Feature clinical course pulmonary tuberculosis is the erasure or absence of symptoms, therefore most cases are detected during preventive fluorography. About a third of patients have a mild intoxication syndrome and signs of damage to the respiratory system.
Signs of intoxication include low-grade fever in the evenings, a feeling of heat, followed by short-term chills, sweating, malaise, decreased appetite, sleep disturbance. Sometimes, with focal pulmonary tuberculosis, as a manifestation of specific intoxication, signs of hyperthyroidism occur: an increase in size thyroid gland, tachycardia, bright eyes, weight fluctuations, irritability. Women may experience menstrual irregularities such as opsomenorrhea or proyomenorrhea.
Complaints of pain in the side, between the shoulder blades, and in the shoulders are possible. The cough is usually intermittent and may be dry or accompanied by scanty sputum production. Occasionally, hemoptysis occurs.
Diagnostics
Physical findings revealed during an objective examination of a patient with suspected focal pulmonary tuberculosis are nonspecific. Palpation reveals slight soreness and stiffness of the muscles of the shoulder girdle; lymph nodes are not enlarged. The percussion sound over the lesion is muffled, harsh breathing is heard during auscultation, and single fine-bubble rales are detected when the patient coughs.
If the data is questionable, test therapy is resorted to: the patient is prescribed anti-tuberculosis drugs for 2-3 months and clinical, radiological and laboratory dynamics are monitored. When the lesions decrease or partially resolve, the diagnosis of focal tuberculosis is undoubted.
Treatment of focal pulmonary tuberculosis
Treatment of active focal pulmonary tuberculosis is carried out in an anti-tuberculosis hospital, inactive - in outpatient setting under the supervision of a phthisiatrician. The standard chemotherapy regimen involves prescribing at least three anti-tuberculosis drugs (rifampicin, isoniazid, pyrazinamide, ethambutol) for a period of 2-3 months. Streptomycin can also be used initially. In the continuation phase, which lasts 4-6 months, two drugs are continued (rifampicin + isoniazid, isoniazid + ethambutol). The total duration of therapy for focal pulmonary tuberculosis is 6-9 months, and in some patients - up to one year. Rehabilitation after a course of treatment is carried out in an anti-tuberculosis sanatorium.
Forecast
The outcome of the focal form of pulmonary tuberculosis is usually favorable. As a result of complete treatment, fresh lesions completely resolve, and a complete clinical cure occurs. At chronic course focal tuberculosis may transform into less prognostically favorable forms (infiltrative, cavernous, disseminated). The most common outcome is pneumosclerosis with the formation of foci of fibrosis or calcification. Such patients require chemoprophylaxis for 1-2 years. The greatest challenge is treating chemotherapy-resistant cases. Prevention of focal pulmonary tuberculosis consists of x-ray examination population, health education work, increasing nonspecific resistance of the body. In reducing the number of cases of secondary pulmonary tuberculosis great importance It has
When performing CT (MR) studies, foci of a dystrophic nature (like gliosis), atrophic nature (like a cerebrospinal fluid cyst), as well as calcification can be detected in the substance of the brain. In chronic tissue ischemia, some other characteristic changes, for example, periventricular leukoaraiosis (changes in the structure and density of the substance around the ventricles), often with the presence of small cysts in the basal ganglia, as well as in the outer and inner capsule of the brain. Signs (of a substitutive nature) are also often identified.
Causes and predisposing factors of changes in the brain
Focal changes include pathological processes that occur in a specific area of the brain. Various changes occur in the brain tissue (scars, cysts, necrosis). The most common focal changes of a dystrophic nature are found:
- In older people. Thus, the probability of identifying dystrophic foci significantly increases with age. Plays a role here pathological changes intra- and extracranial vessels, narrowing of the vascular lumen and cerebral ischemia provoked by these factors.
- In persons suffering diabetes mellitus. With this pathology, angiopathy often occurs, manifested by changes vascular wall, impaired vascular permeability, impaired vascular patency. Against this background, strokes often occur.
- In people with other angiopathy, developmental anomalies vascular bed brain (for example, open circle of Willis), thrombosis (disturbances of the lumen of another etiology) of extra- and intracranial arteries.
- In persons with exacerbation cervical osteochondrosis. When the disease occurs, the brain stops receiving sufficient oxygen. As a result oxygen starvation areas of ischemia appear.
- For those who have suffered a skull or brain injury. Restructuring of the brain substance at the site of contusion after injury can lead to the appearance of a focus of gliosis, cyst or calcification.
- In persons exposed to long-term intoxications (exo- or endogenous). Thus, the first group includes people who abuse alcohol, take toxic substances (or are exposed to them at work, for example, workers in paint production workshops). The second category includes people with long-term diseases (infectious, inflammatory).
- In patients with oncological processes of the brain, dystrophic foci are detected during examination.
Methods for identifying dystrophic foci in the brain
The main methods for identifying dystrophic (and other) parenchymal lesions in the brain are CT and MRI. The following changes can be identified:
- Gliosis type lesions.
- Cystic areas due to atrophy (and trauma).
- Calcification (as an example, due to impregnation of the hematoma with calcium salts).
- Periventricular leukoaraiosis. Although it does not directly relate to focal changes, it is a significant marker of chronic ischemia.
On a CT scan at the level of the third ventricle and posterior horns of the lateral ventricles, blue arrows indicate areas of a cystic nature (the result of necrosis of the brain substance in the past): small in the area of the right thalamus and larger in size in the occipital lobe on the right. There is also a change in the density of the brain matter around the posterior horn of the right lateral ventricle. The Sylvian fissures are widened, which indicates hydrocephalus (atrophic, replacement).
On the CT scan at the level of the bodies of the lateral ventricles, blue arrows indicate cystic (atrophic) areas in the parietal and occipital lobes on the right (consequences of a stroke). Signs of chronic cerebral ischemia are also visible, more pronounced on the right (periventricular leukoaraiosis).
CT scan of the head at the level of the 4th ventricle, cerebellar peduncles: in the left hemisphere of the cerebellum (at the base, near the left cerebellar peduncle) there is an atrophic area (consequences of a stroke). Notice how the outer cerebrospinal fluid spaces of the brain are expanded.
Blue arrows on the CT scan indicate areas of periventricular leukoaraiosis (around the anterior and posterior horns of both lateral ventricles). The red arrow also indicates “fresh” (on the right in the occipital lobe).
The presence of dystrophic focal changes in the brain in many cases is a consequence of chronic ischemia and is often combined with atrophic (replacement) hydrocephalus, especially in people who drink alcohol long time those exposed to intoxications of a different nature, who have previously suffered a stroke or head injury.
A CT scan of the head shows signs of replacement hydrocephalus (due to necrosis of the brain parenchyma), with the presence of multiple atrophic foci on the left side - in the occipital lobe (1), in parietal lobe(2) and with right side– in the region of the head of the lenticular nucleus, periventricular to the body of the ventricle (3). The diameter of the lateral ventricles is expanded (marked by an arrow). Around the horns of the lateral ventricles there is a hypodense (low density on CT) zone.
Results
Dystrophic focal changes can be detected by CT and MRI in the brain of any person. Their detection may indicate a previous pathology (traumatic, ischemic). If the lesions are small in size and localized in peripheral parts brain or in the white matter, basal ganglia, the prognosis for the patient’s future life is favorable. But focal changes in the brainstem localization, on the cerebral peduncles, and thalamus are more unfavorable and can cause the appearance of neurological symptoms.
Focal formations in the lungs are tissue compactions, which can be caused by various ailments. Moreover, for installation accurate diagnosis A doctor's examination and x-rays are not enough. The final conclusion can only be drawn on the basis specific methods examinations, including blood tests, sputum tests, and tissue punctures.
Important: the opinion that only tuberculosis can be the cause of multiple focal lung lesions is erroneous.
We can talk about:
Therefore, diagnosis must be preceded by a thorough examination of the patient. Even if the doctor is sure that the person has focal pneumonia, it is necessary to perform a sputum analysis. This will identify the pathogen that caused the development of the disease.
Now some patients refuse to undergo certain specific tests. The reason for this may be reluctance or inability to visit the clinic due to its distance from the place of residence, or lack of funds. If this is not done, then there is a high probability that focal pneumonia will become chronic.
What are foci and how to identify them?
Now focal formations in the lungs are divided into several categories based on their number:
- Singles.
- Single – up to 6 pieces.
- Multiple – dissemination syndrome.
There is a difference between the internationally accepted definition of what lung lesions are and what is accepted in our country. Abroad, this term refers to the presence of areas of compaction in the lungs of a round shape and a diameter of no more than 3 cm. Domestic practice limits the size to 1 cm, and the remaining formations are classified as infiltrates, tuberculomas.
Important: computer examination, in particular tomography, will allow you to accurately determine the size and shape of the lesion lung tissue. However, it is necessary to understand that this examination method also has its own error threshold.
Actually, focal formation in the lung is a degenerative change in the lung tissue or the accumulation of fluid (sputum, blood) in it. Correct characterization of single pulmonary lesions (SLP) is one of the most important problems of modern medicine.
The importance of the task lies in the fact that 60-70% of such formations that were cured, but then reappeared, are malignant tumors. Among total number The proportion of AOLs identified during MRI, CT or radiography is less than 50%.
An important role here is played by how lesions in the lungs are characterized on CT. With this type of survey, based on characteristic symptoms, the doctor may make assumptions about the presence of such serious illnesses, such as tuberculosis or malignant neoplasms.
However, to clarify the diagnosis it is necessary to take additional tests. Hardware examination is not enough to issue a medical certificate. Still everyday clinical practice does not have a single algorithm for carrying out differential diagnosis for all possible situations. Therefore, the doctor considers each case separately.
Tuberculosis or pneumonia? What can prevent, with the modern level of medicine, from making an accurate diagnosis using the hardware method? The answer is simple - imperfect equipment.
In fact, when undergoing fluorography or radiography, it is difficult to identify a primary tumor whose size is less than 1 cm. Interposition anatomical structures can make larger lesions virtually invisible.
Therefore, most doctors advise patients to give preference computed tomography, which makes it possible to examine the tissue in cross-section and from any angle. This completely eliminates the possibility that the lesion will be obscured by the cardiac shadow, ribs, or roots of the lungs. That is, radiography and fluorography simply cannot consider the whole picture as a whole and without the possibility of a fatal error.
It should be taken into account that computed tomography can detect not only AOL, but also other types of pathologies, such as emphysema and pneumonia. However, this examination method also has its own weak spots. Even with a CT scan, focal formations may be missed.
This has the following explanations for the low sensitivity of the device:
- The pathology is in the central zone – 61%.
- Size up to 0.5 cm – 72%.
- Low fabric density - 65%.
It has been established that with a primary screening CT scan, the probability of missing a pathological change in tissue, the size of which does not exceed 5 mm, is about 50%.
If the diameter of the lesion is more than 1 cm, then the sensitivity of the device is more than 95%. To increase the accuracy of the obtained data, additional software for 3D imaging, volumetric rendering and maximum intensity projections.
Anatomical features
In modern domestic medicine, there is a gradation of lesions based on their shape, size, density, structure and condition of the surrounding tissues.
An accurate diagnosis based on CT, MRI, fluorography or radiography is possible only in exceptional cases.
Usually in the conclusion only the probability of the presence of a particular disease is given. In this case, the location of the pathology itself is not given decisive importance.
A striking example is the presence of a lesion in the upper lobes of the lung. It has been established that this localization is characteristic of 70% of cases of detection of a primary malignant tumor of this body. However, this is also typical for tuberculous infiltrates. With the lower lobe of the lung there is approximately the same picture. Here, cancer that has developed against the background of idiopathic fibrosis and pathological changes caused by tuberculosis are detected.
Great importance is given to the contours of the lesions. In particular, a fuzzy and uneven outline, with a lesion diameter of more than 1 cm, signals a high probability of a malignant process. However, if clear margins are present, this is not sufficient reason to stop diagnosing the patient. This picture is often present in benign neoplasms.
Particular attention is paid to tissue density: based on this parameter, the doctor is able to distinguish pneumonia from scarring of lung tissue, for example, caused by post-tuberculosis changes.
The next nuance is that CT allows you to determine the types of inclusions, that is, determine the structure of the OOL. In fact, after an examination, a specialist can tell with high accuracy what kind of substance accumulates in the lungs. However, only fatty inclusions make it possible to determine the ongoing pathological process, since all the others do not belong to the category of specific symptoms.
Focal changes in the lung tissue can be provoked by both a fairly easily treatable disease - pneumonia, and more serious ailments - malignant and benign neoplasms, tuberculosis. Therefore, it is important to identify them in a timely manner, in which a hardware examination method - computed tomography - will help.
