CT of small peripheral lung cancer diagnosis

 A focus on basic pathological basis of CT signs and the analysis of Radiology, PLA General Hospital
Caizu Long
Lung cancer is one of the most common malignant tumor. In recent years, the incidence of lung cancer was significantly increase. Beijing, Shanghai , Tianjin, Jiangsu and Liaoning Province, the city, Yunnan old areas, the incidence of lung cancer and / or mortality accounts for a variety of malignant tumors of the first. more than the time of diagnosis of lung cancer has been to the middle and late, 70 to 80% of patients had lost radical opportunity to improve the five-year survival rate of patients is very important. CT is the most important early peripheral lung cancer, the most reliable screening method.
one routine inspection methods
do first scan, slice thickness 8-10mm to determine the anatomical lesions. and then the line of lesion thickness of 1.5 to 3.0 HRCT scan or continuous scan. such as the spiral, the lesion can be 3mm thick volume scan, then 1 ~ 3mm reconstruction. The scan can be made lesions of the internal structure and its adjacent edge features clearly show the relationship between organizational structure. If there are difficulties in diagnosis who do dynamic enhanced MRI lesions in order to strengthen the situation of the lesions observed.
CT of small peripheral lung cancer characteristics and signs The pathological basis of
1, signs of lung tumor edge features:
(1) lobulation: small peripheral lung cancer is the most common basic signs. hospital 100 cases of small-diameter less than 3cm of lung lobulation rate was 84%. the vast majority of small lung cancer dark leaf, from the long chord distance and the ratio of> 2 / 5. The pathological basis of one edge of each part of the tumor with varying degrees of tumor cell differentiation, the growth rate of the different relevant . Second, the interval of the lung tissue into the tumor's blood vessels, bronchi branch out from the growth of tumor blood vessels and connective tissue can cause tumor growth retardation; have lacunae, thus forming a leaf shape.
( 2) The rough edges: see fine, short spikes, spike-like protrusions or jagged changes. This is a common sign of lung cancer, the occurrence rate of about%, the performance is due to the tumor stroma, blood vessels outside the tumor growth and spread of tumor cells into the surrounding due.
2, the performance characteristics of CT within the tumor: the majority of the density of small peripheral lung cancer than the uniform, may have vacuole sign, thin air bronchogram, ground-glass honeycomb sign and symptoms, a few cases can still see the calcification .
(1) bubble sign: Refers to the small focal nodular area of sexual transmission. The diameter of <5mm, and lung cancer to empty distinction. can be single or multiple. such as the number of dense vesicles gathered in with honeycomb, said honeycomb sign. The pathological basis for the tumor tissue is not occupied �� gas lung tissue; �� not closed or expansion of small bronchi; �� papillary carcinoma gas cavities between the structure; �� along the alveolar wall growth of alveolar carcinoma and melting is not closed, alveolar destruction and enlargement; �� small focal necrosis within the tumor formed after discharge. This levy more common in bronchioloalveolar carcinoma and adenocarcinoma, is also found in squamous cell carcinoma. Sometimes, the vacuoles internal mucus, shedding of tumor cells in the presence of such components can be made higher CT value, approximate density of water. in the lung appear as a small window on the fuzzy low density bubble in the mediastinal window showed a small bubble on the translucent film.
(2) thin air bronchogram: was thin strip, about 1mm diameter, air density shadow, or in a small bubble-like (diameter <1mm = air density shadow, seen for several consecutive adjacent level, pathology for the expansion of the bronchioles. found in bronchioloalveolar carcinoma or adenocarcinoma.
(3) Cellular Characteristics: integration by a number of cellular vesicles, more consistent in size, this sign only in lung cancer. pathology is the growth of cancer cells along the alveolar walls, alveolar space is not closed, so that mucus left over from the expansion chamber.
(4) ground-glass sign: the whole part of the tumor nodule or nodules were ground area density glassy lighter, it does not pulmonary vascular cover texture. lesion state general still clear. The pathological basis of the growth of tumor cells along the alveolar wall, alveolar wall thickening, but did not block the alveolar cavity, a small amount of mucus within the tumor or off, this sign only in lung cancer .
(5) empty: To more than 5mm round or oval-like low density of air, hospital 100 cases of small peripheral lung cancer occurred within the cavity was 4%. a small hole in the wall thickness of lung cancer is not thin are, uneven wall, there are mural nodule. hole was centered or eccentric place. individual cases meager wall. the edge of the tumor was still visible changes in leaf and burr. empty most of the tumor necrosis Department of liquefied bronchial interlinked, formed after discharge.
(6) calcification: within small peripheral lung cancer with calcification. HRCT reported in the literature on the detection of lung cancer calcification rate can reach 15.8%. our hospital report 100 patients with small lung CT scan detected by TLC 3 cases. calcification showed fine gravel-like, small nodular, diffuse, or indulge in the side of the distribution.
calcification mainly seen in squamous cell lung cancer, adenocarcinoma. The pathological basis �� dystrophic calcification. due to tumor blood supply barriers, tumor cell degeneration, necrosis, local calcium level changes, calcium deposits; �� calcification of the tumor had wrapped before, occurred in the pre-existing calcified granuloma; �� calcification of the primary tumor, mainly seen in mucinous adenocarcinoma. < br> 3, the tumor adjacent to the CT signs of structural change (1) vascular accumulation sign: is gathered around the blood vessels to the nodules. vessels in the tumor edge interrupt or through the tumor. artery and vein may be involved. For the good of them involving the pulmonary vein, is important to identify malignant. Despite reports in the literature of benign lesions are also visible signs of vascular accumulation, but our experience gathered benign vascular lesion detection rate is not high, and reach of small lung cancer. (2), pleural indentation: There are three main performance: �� When the recessed center and the level of parallel scan showed pleural indentation mm typical of tumors and adjacent chest wall or between the triangular shadow, said bell, and its tip is connected with the linear opacities; �� When the level of deviation from the depression center, the line shaped into a film by the two or more, sometimes with the tumor gradually reflected in its separate video from a big big triangle into two smaller triangles; �� level of crack and oblique attack showed pleural indentation curves shadow. Zhiyong Zhang reports of small peripheral lung cancer detection rate of pleural indentation 93%. mainly seen in the adenocarcinoma and bronchioloalveolar carcinoma. The pathological basis of the general opinion of the lesions caused by fibrous scar tissue contraction. cicatricial contraction of fiber grid near the tumor passes through to the visceral pleura, the visceral pleura pull to the tumor foci. indentation and the parietal pleura gap between the composition, the liquid filling the living rational.
(3) pleural tumor shadow on fuzzy little piece, there is about 10% for the small signs of bronchial obstruction.
(4) satellite lesions: In addition to individual cases of adenocarcinoma lesions can occur outside the sub, all showed solitary nodules, no satellite lesions, the Court was no case of 100 patients with small lung cancer satellite lesions.
4, the CT enhancement characteristics of lung cancer and benign lesions
between the blood supply and metabolism are very different, so the use of enhanced MRI in differentiating benign and malignant lesions is important.
first foreign scholars Swenson report of 163 nodules enhanced scan results, including 111 malignant nodules (lung cancer and metastases) the median increase was 40HU, (20 ~ 108HU), and 58 benign lesions, the median increase was only 12HU. with 20HU as a threshold for distinguishing benign and malignant tumors was 100% sensitivity, specificity and accuracy were 76.9% and 92.6%. Yama *** a threshold such as the use of 20HU the findings of the study and about the same. Zhang Minming other diameter of 65 <3cm in the determination of solitary pulmonary nodules increased its rate of time-density curve, peak, and flow perfusion and contrast enhancement patterns between benign and malignant tumors vary. Malignant tumors of the curve rises faster than fast curve after the peak remained at high values. inflammation type, vary between benign and malignant tumors. rate of malignant tumors of the curve rises rapidly, peaking after the curve remained at high values. inflammatory mass of the time-density curve rises faster and the peak high peak decreased slightly after the curve, and then increased again. benign tumor of the time density curve low and flat, or almost no increase. malignancies enhanced peak 41.9HU, inflammatory mass of the peak 43.6HU, benign tumors were significantly higher than the peak (13.4HU). malignancies and inflammatory mass of the blood flow was significantly higher than benign tumor blood flow. enhance the way there are also different, 55% of malignant nodules showed significantly enhanced uniform, begins as a 30% increase is not homogeneous, but most of them gradually after the peak tends to increase homogeneity, and inflammatory tumors in the peripheral part of the increased heterogeneity of the main, and mostly benign tumors do not enhance or edge enhanced.
In short, the enhanced features of lung cancer can be summarized as �� enhanced amplitude, over 20HU; �� time density curve rises faster; �� high blood flow; �� 85% of patients ultimately homogeneous enhancement. These characteristics and lung cancer The new small blood vessels and structural features more relevant, and strong on the tumor tissue metabolism.
three different histological types of lung cancer CT of small peripheral performance analysis
some histological types of lung cancer CT manifestations of small certain characteristics, according to these characteristics, can be broadly inferred their histological type.
1, BAC Bronchioalveala Carcionma abbreviated BAC: Case of large numbers in the subpleural or near the leaves of the pleura, irregular shape, were small pieces and can be star, the internal structure of features, the main signs of air-bronchogram, bubble sign, cellular sign, ground-glass sign, the signs appear high. hospital 63 cases of solitary bronchioloalveolar carcinoma incidence of vacuole sign ( 33) 52.38%, air bronchogram in 21 cases (33.33%), ground-glass sign in 12 cases (19.04%). including ground-glass sign with alveolar cell carcinoma-specific symptoms only. of the performance is still seen as the only two cases uniform density, the density was reduced with the increase of grain like mulberry-like changes.
2, adenocarcinoma: leaf, glitches, blood vessels together, depression and other signs of pleural more significant. vacuole sign and air bronchogram are more common. a small number of vacuoles and more than bronchioloalveolar carcinoma. sometimes see multiple foci, the Department developed on the basis several times due to scar; disease that is relatively small shift, but also a feature of large metastases.
3, squamous cell carcinoma: The main signs are deeply divided leaves, small focal necrosis in the formation of vesicles or empty sign, burr and sawtooth sign, pleural indentation, such as adenocarcinoma of the typical vascular aggregation.
4, small cell carcinoma: peripheral Small cell carcinoma of the lack of the cancer, lung cancer, which has a leaf, glitches, such as cavitation and air bronchogram signs, often very small tumors have significant hilar and mediastinal lymph node metastasis and distant metastasis. lesion itself over the edge finishing, no leaf, density of cross-over are exactly like benign tumors. When the detection of brain metastases, and 10 ~ 15%, can also be transferred to the contralateral lung, adrenal gland, liver, etc..
IV lung cancer Diagnosis and differential diagnosis of
1, lung cancer should be aware of the following links
(1) to correctly identify the basic signs of lung cancer, and a deep understanding of the pathological significance of their representatives, this is the premise correct diagnosis of lung cancer.
(3) improve the diagnosis of some special significance signs of awareness. such as ground-glass density, lighter and its symptoms easily misdiagnosed as inflammatory disease. According to our experience, this is very bronchioloalveolar carcinoma diagnosis, low-density and high density granular same lesions in addition to outside BAC not yet seen. pleural side of the fuzzy little piece of film I saw in the cancer nodules.
(4) on the significance of calcification: calcified lesions appear not to exclude the basis of lung cancer, to be combined with lesions to the overall performance of a comprehensive analysis. based only on the calcification within lesions diagnosed as benign lesions is not desirable. I have two cases of hospital based only on the neglect of the other signs of calcification in the analysis was misdiagnosed as tuberculosis.
reasonable application of enhanced scan, according to disease shape, size, edge of the signs, pathological features of the internal structure, is adjacent peritumoral tissue CT, 85% to 90% of small lung cancer should be able to make a diagnosis, without enhancement. but there are a small part of the basic signs of lung cancer cases occur less , the performance is not typical, then the dynamic CT should be enhanced MRI lesions, differential diagnosis can provide useful information. such as dynamic contrast-enhanced scan can not confirm the diagnosis should be made by CT guided percutaneous biopsy or transbronchial lung biopsy , or short-term intervals after treatment. most of peripheral lung cancer in 1 to 3 months may have changed size.
2, the differential diagnosis of
(1) Tuberculosis: the edge of more smooth, clear, no leaf or only shallow leaf, can be a bit like or mottled, patchy calcification, may also have holes, the hole was at risk or crack like most around the lesion with satellite lesions, easily identified by these signs and lung cancer. within a few TB lesions for special treatment after discharge of caseous necrosis can be displayed vacuolar changes need to identify with bronchioloalveolar carcinoma, but the combination of lung cancer and other imaging characteristics of TB in general is not difficult to identify.
(2) hamartoma: a typical Hamartoma of fat and calcification within its symptoms were of the popcorn-like, smooth, sharp edge of the tumor more than a shallow leaf or leaf-free. individual cases neither calcification nor fat density, and leaf dark, at this time misdiagnosed as lung cancer. but occasionally leaf hamartoma can be deeper, the general absence of other malignant characteristics, such as burrs, air bronchogram, small cavities, such as pleural indentation, and no hilar and mediastinal lymph nodes, etc. signs. enhanced scan enhancement is not obvious, CT added value of more than <20HU.
(3) Other benign tumors: lesion density, smooth edge, notch leaf was not obvious, many fine, short spikes and saw no sign and pleural depression and other signs of malignancy.
(4) spherical pneumonia: more in the lower lung field, edge and more fuzzy, peripheral vascular texture increased, thickening, adjacent pleural reaction is more extensive lesions CT value is lower, more in the 20 ~ 25HU, often the clinical history of recent fever, increased white blood cells, the short-term (7 to 10 days) after infection resistance more than a narrow focus.
(5) small bronchogenic cyst: bronchogenic cyst containing fluid in the lungs, can be presented in isolation nodular shadows, CT showed a clear edge mass, density, CT value of 0 ~ 20HU, but when abundant protein components within the cyst, CT values of up to 20HU above, the performance of enhanced scan without enhancement. Sometimes there are lesions air into the gas density affect the formation of vacuoles is required and the identification of bronchioloalveolar carcinoma.
(6) fungal infections:
(7) arteriovenous fistula:
bronchioloalveolar carcinoma Imaging
PLA General Hospital Caizu Long Zhao Shaohong
bronchioloalveolar carcinoma, although still classified as lung cancer, but significantly different from other cancer, has its tissue and morphological characteristics, have different origins, performance and prognosis, and therefore, scholars believe that should the WHO classification of BAC from adenocarcinoma carved out, as lung cancer can exist independently of a type. In recent years, some research data shows that the developed countries, BAC were significantly increased. Barsky statistical analysis of 1955 1990 than 1527 cases of lung cancer constitutes the dynamic changes of various types found that squamous cell carcinoma from 56.1% (1955 to 1960) decreased to 22.2% (1986 to 1990); the same period, adenocarcinoma (including BAC) rose from 14.6% to 46.5%, much higher than squamous cell carcinoma. BAC's growth is particularly significant, from 1955 to 1960, only 5% of lung cancer, 70 years since the rapid rise to 1985 to 1990 reached 24%. squamous cell carcinoma is almost equal. rather than BAC lung cancer did not change significantly, indicating that the rise in lung cancer incidence rate increase was mainly due to BAC. This Auewbach (USA 1991) and Ikeda (*** 1991) of roughly the same results.
a , by gross pathology and clinical pathological
, BAC can be divided into three types: (1) solitary nodule: both in the lung periphery, in the pleura, the diameter of 0.7 ~ 4.5cm, round or slightly sub- lobulated, gray-white cut surface, usually without necrosis; (2) multiple nodules: the formation of nodules, scattered in the lung of the leaf or leaves, or lungs, nodules are still visible between the normal lung tissue; (3) diffuse: the number of cancer often leaves or lung involvement, texture hard, like a lobar pneumonia, it said the pneumonia-like type. section often has translucent material associated with mucus production. The first type of sputum examination was negative, the latter two types are mostly positive.
light microscope, the organizational structure and morphology under different, BAC can be divided into four types: (1) alveolar cell types: well differentiated cancer cells, columnar, along the original growth of the alveolar wall, similar to normal tissue formation and alveolar-like structures, and stromal invasion; (2) papillary type: lung structure essentially remains, but the prominent feature is the formation of many different sizes of nipple stretching alveolar cavity, the nipple is still some branches slender fibrovascular stroma formation of the axis, the above two types, PAS and Oseen blue staining, cells were negative; (3) mucous cell type: the cells lining the alveolar walls high columnar thin mucus can also be spread only a few cells in alveolar walls, in addition found in mucous cells, are also often filled with alveolar; (4) mixed type: the above three types of hybrid.
BAC, or a different tumors, electron microscope, the source of its four types: (1) Most of the cases originated in the terminal bronchioles ciliated Clara epithelial cells; (2) a small number of cells from alveolar type ��; (3) of the bronchioles Health breast epithelial mucin; (4) Mixed type: the existence of various types of cells were mixed.
isolated type BAC, the majority of patients with no symptoms, the examination found that a small number of patients may have cough, sputum, chest pain, etc. General respiratory symptoms chilblains, individual cases may have bloodshot sputum. diffuse BAC, the majority of patients with severe symptoms, mainly cough, sputum slightly white mucus, quantity, may also have bloody sputum, chest tightness, shortness of breath, chest pain, weight loss, clubbing finger and so on. generally do not heat, when the infection can be hot.
II, X-ray
bronchioloalveolar carcinoma has been a lot of X-ray findings reported in the literature, it can be divided into three types. (1) solitary nodule: lesions were round, pale round or sheet film, rough edges, partakers leaves, burrs, may have depression or pleural pleural tail sign, uneven density lesions, visible air bronchogram phase and vacuole sign. (2) inflammatory: lesions were more inflammatory lung segment or lobe-like consolidation, consolidation area density of the majority of high volume part of the enlarged or reduced, split between straight and curved leaf depression or to outside the carina, showing bronchial air like, honeycomb-shaped gas cavity or vacuole sign. (3) diffuse nodules: miliary and diffuse lung nodules dense shadow, ranging in size, uneven distribution of asymmetry, for the lower lung fields in two with some clear edge and some of the more vague, could be fused into a sheet film, and some showed an increase in mesh texture.
addition to the above three types, but still shows the existence of several mixed X-ray findings.
III, CT performance
bronchioloalveolar carcinoma in lung cancer accounts for about 2% ~ 24%, CT can be divided into isolated type, multi-nodular type and diffuse type.
(a ) isolated type: X-ray on the often ambiguous realm of fuzzy short film video, is often misdiagnosed as pulmonary tuberculosis or inflammation, or for lesions smaller and missed, but there are certain characteristics in the CT, the general can make correct diagnosis. According to the PLA General Hospital 63 cases of solitary bronchioloalveolar carcinoma of the CT signs and pathology research, and reported in the literature, isolated alveolar type addition to the general lung cancer CT signs (leaf, glitch, vascular convergence, pleural retraction, etc. ), there are the following characteristics: (1) lesions in the lung or pleural field next week. (2) can be star-shaped or irregular patchy. (3) vacuole sign (false lumen) appears high , BAC's vacuole sign about 52.38% (33/63). The so-called bubble sign is within the small focal nodular area of transmission, the diameter of <5mm, and the lung cavity to different, sometimes including the gas compartment irregular, ranging from the strip and the width was cystic. BAC vacuole sign of the pathological basis of tumor tissue that is not occupied by gas in lung tissue; not closed or expansion of small bronchi; papillary carcinoma of gas between the structure compartment (this is seen in papillary type); growth along the alveolar septum carcinoma bubble chamber is not closed and melting, destruction and expansion of the alveolar cavity, and sometimes internal cavity mucus, shedding of tumor cells in the presence of components can be made CT value is increased, the density similar to water. (4) thin air bronchogram: was thin strips (diameter l1mm) air density shadow, seen for several adjacent level, the pathology for the expansion of the bronchioles. its occurrence have a higher rate, about 33.3% (21/63). (5) cellular sign: the number of vesicles into the cellular concentration, more consistent in size, sometimes very fine vesicles, the lesions showed fine grid to change. (6) ground-glass density: the entire tumor nodule or nodules of the lighter part of the regional density of glassy mill was vague, it does not cover up the texture of pulmonary vascular lesions realm still clear. The pathological basis of the same tumor cells along the alveolar septum growth, alveolar wall thickening, but the alveolar space is not blocked, a small amount of mucus within the tumor cells or shedding. CT showed pathologic lesions of ground-glass density area of non-mucinous BAC, the consolidation of the alveolar region mucinous cancer. a ground-glass density that the Department of bronchioloalveolar carcinoma of the early signs, PET examination often is holiday, indicating that this time the slow tumor growth, metabolism, lower level. (7), pleural indentation rate of 85.91% occurs (54 / 63), the result of tumors located in the subpleural fibrous tissue and tumor characteristics of successful formation of fibrous tissue caused much about. (8) individual cases of disease shows high density and low density white granular change was mulberry-like.
(b ) multiple nodules: a lobe, or the side of the lung or lungs scattered distribution of nodules, nodule size range, shape and isolation of each type of BAC nodules similar.
(c) of the diffuse type: There are two cases: (1) In patients with more than one lung segment violation of a lobe or a few leaves; (2) numerous small nodules or small plaques distributed in both lungs filled with shadow. Since this type of lung cancer, a majority of cases for the mucous cell type, often secrete large amounts of mucus, can produce pulmonary consolidation and air bronchogram images, and blurred the edges of the shadow of consolidation, the boundary is unclear, it is in the film, is often mistaken for pneumonia or tuberculosis. this type BAC of about accounted for 37% of BAC cases, according to lesion morphology can be divided into four types: hive-based, real variant, multifocal, mixed. According to the literature can be grouped into five characteristic CT signs: (1) hive levy: The lesions uniform density region, showing honeycomb-like air chamber, large and small, are round and oval low density (close to the air). The pathological basis of cancer cell growth along the alveolar bronchioles, but does not destroy its basic structure, and its irregular thickening of the alveolar space it exists in varying degrees. This sign and air bronchogram exist, there are qualitative significance. (2) The air bronchogram: acute inflammatory diseases in general is different from its bronchial wall is characterized by irregular, uneven, narrow universality; bronchus was stiff, twisted; mainly large developing bronchi, small bronchi and more can not be displayed, showing dendritic dry, the air bronchography with pneumonia symptoms performance difference. (3) ground-glass signs: involvement of lung tissue was similar to the density of water samples showed a grid-like structure of ground glass appearance, based on the pathological thickening of the alveolar septum involvement within the framework composed of protein full of mucus or other exudate . (4) consolidation of lung segments and angiogram sign: increased visibility before scanning lobe or lung lesions in the distribution segment, showing wedge consolidation, hilar lesions sharp point, attached to the external and pleural; density, uniform, edge straight, can also be slightly convex or concave, without air bronchogram; enhanced low-density region shows uniform enhancement of vascular dendritic film. (5) patchy distribution of both lungs filled with nodules. individual cases, nodular or cystic changes within the cavity, suggesting it may be the cause of nodule central necrosis, is more likely with the terminal bronchioles of the valve obstruction. (6) Observation: There were increasing, increasing .
IV diagnosis and differential diagnosis
(a) Solitary bronchioloalveolar carcinoma: the addition of a solitary pulmonary nodules with CT signs of the general lung cancer: a leaf, glitch, pleural indentation, vascular convergence and other signs of In addition, as CT also has some other features, such as lesions located in peripheral or subpleural, was under the sheet or stellate lesions uneven density, with fine air bronchogram film, bubble sign (false lumen), hive levy, symptoms such as ground glass, generally suggest the diagnosis of BAC. in which symptoms and ground-glass cellular rarely in other types of lung cancer symptoms appear, has high diagnostic value. of the performance is still seen as the only three cases of uneven density, showing particles like high density, surrounded by signs of low density, such signs have not yet isolated in other types of nodules seen, so the importance of the diagnosis of BAC.
isolated type BAC and other isolated lesions need to identify The main consideration should be given the following lesions.
1. TB nodules or tuberculoma: the majority of lesions leaf edges smooth and no glitches, calcified lesions seen in the meticulous manner, the distribution was diffuse or uniform consistency, CT value of the tall in 160Hu, may have marginal empty, showing crack-like or crescent around most of them have satellite lesions, localized pleural thickening more common, generally is not difficult to identify with the BAC. but the individual TB change, caseous necrosis after discharge reduce the density of small bubble formation zone, exactly like the false lumen BAC, can lead to misdiagnosis. at this time whether the BAC should be noted that other features of disease, such as pleural indentation, vascular convergence sign, air bronchogram, etc., no such signs of TB and more.
2. small bronchogenic cyst: bronchogenic cyst containing fluid in the lungs showed a solitary nodule can, CT showed a sharp smooth edges, uniform density, CT value between 0 ~ 20Hu, generally have no difficulty in identification. But when cyst proteins to become rich, the up 30Hu above, the secondary infection, cysts and more individual bronchioles no pleural indentation, vascular sets grams, etc., void as the air density, through the brightness is high, the BAC of the false lumen and the general ( often fluid and cellular components within, CT value is slightly higher than the air) different.
3. metastases: metastases have various forms, usually multiple lesions, different size, shape similarity, as metastases from the lung capillary vein, and therefore no relationship between lesion and bronchial. Solitary metastases, smooth edges, burrs and saw no more sign, air bronchogram and bubble-free sign.
4. spherical pneumonia: mostly round or oval edge less clear and uniform density of solid lesions, peripheral vascular thickening texture (no vascular cluster), adjacent pleural reaction significant short-term review of anti-infection treatment gradually reduced.
5. and can produce changes in ground-glass-like disease identification: the limitations of this type of lesion of lung infection, eosinophilia disease, hemoptysis into the lungs, intestines and pancreas, and lung metastasis. realm of the obscure diseases of pulmonary infection, irrespective of leaf change, and AC disease state more than clear, often accompanied by vacuoles, and many partakers leaves. hemoptysis in patients with pulmonary ground-glass amorphous, no leaf, no other signs of lung cancer. eosinophilia syndrome with focal infection of CT performance similar; blood eosinophilia diagnosis. bowel and pancreas lung metastasis of primary tumor manifestation. In short, on the ground glass can produce pathological changes in addition to attention to morphological identification, the should be closely combined with clinical performance, to analyze and judge, and can be an accurate identification.
(b) of the diffuse type bronchioloalveolar carcinoma (DBAC): DBAC the CT signs of varying degrees of specificity, and each sign both may appear alone, but also exist, several combined can greatly improve the accuracy of diagnosis. hive-like translucent areas, two each with ground-glass air bronchogram sign (dead tree sign) or to review the increase to determine diagnosis. above (1), (2), (3) individual should be highly suspect of the disease. uniform consolidation plus single (6) should think of the possibility of DABC.
because DBAC lung segment or lobe to the distribution of edge blur has air bronchogram and so easy to mistakenly believe that lobar pneumonia with caseous pneumonia, was uniform when the DBAC consolidation with atelectasis similar air bronchogram within the consolidation and lymph node disease in lymphoma fungoides can also be appears to diffuse small nodules performance DBAC resemble miliary tuberculosis, should be careful to distinguish these lesions.
1, lobar pneumonia: typical CT imaging showed signs of bronchial air, the bronchial wall soft, non- rigid sense, the natural branches, bronchial diameter by the coarse to fine, like the liver-like branches, and DBAC the air bronchogram showed a leafless tree is like. lobar pneumonia is not associated with cellular levy levy and ground glass, often significantly history of acute infection.
2. Tuberculous pneumonia: bronchial angiography shows typical air sign, often accompanied by a variety of other lung field tuberculosis, tuberculous intoxication obvious clinical symptoms.
3. lymphomatoid granuloma: air bronchogram may have, it should DBAC identification. The former lesion often has agglomerate density more uniform, state clearly, do not sign with the ground glass with cellular sign, lesion development was slow.
4 . Lymphoma: Can the distribution was segmental and lobar have air bronchogram, and DBAC similarities, but mostly air bronchogram inflatable bronchial tree trunk, bronchial edge smooth, no dead branches like change. is not accompanied by signs and ground glass hive levy.
5. atelectasis: general significantly smaller in size, leaves significant shift between the split and concave arc, compensatory emphysema adjacent lung tissue, and DBAC real variable volume reduced light, leaves were split between the limitations and wavy convex, the adjacent lung tissue was no significant compensatory changes.
6. miliary tuberculosis: diffuse distribution of small nodules, density, even size, uniform issued; edge of the fuzzy segment, showing interstitial distribution. DBAC the size of small nodules often uneven, the edge clearer, distribution to the middle and lower lung field as the combination of clinical, generally can be identified between the two.
more slice spiral CT in the chest, the application of PLA General Hospital Caizu Long