医学影像学（Medical imaging）

1、医学影像学（Medical imaging）Natural contrast: the structure of human tissue is based on differences in density, which produces X - ray contrast. This natural difference is called natural contrastIn contrast to tissues or organs lacking natural contrasts, the class believes that the introduction of substan

2、ces above or below the density to produce contrast is called artificial contrastMethods of contrast: 1 direct introduction: oral perfusion, puncture and injectionIndirect introduction: intravenous infusionApplications of X-ray diagnosis: gastrointestinal tract, musculoskeletal system and chestFlow v

3、oid effect: liquid flows, not to signal acquisition in the imaging process and showed no signal shadow.Doppler effect: the frequency of reflected wave changes when the ultrasonic meets the reflecting interface of motion.Posterior wall echo enhancement: the absorption and attenuation of acoustic ener

4、gy are different in normal tissues and diseased tissues, and the posterior wall echo is enhanced when the fluid cyst or abscess with low attenuation coefficient is found.Sound shadow: high attenuation coefficient of fibrous tissue, calcium plaque, stone, gas, etc., behind the formation of sound shad

5、ow.The basic pathological changes of bone tissue:1, osteoporosis: refers to a unit volume of normal bone tissue calcification is reduced, organic ingredients and calcium salt of bone tissue decreased, but the proportion of organic components and calcium salt content of bone is still normal X-ray fin

6、dings: mainly decreased bone mineral density, bone in the bone trabecula of reduction, the gap widened, cortical bone delamination and thinning; disappearance of vertebral body structure, vertebral body becomes flat, the lower edge of the concave, vertebral gap widened.2, osteomalacia: refers to a c

7、ertain volume of organic tissue in bone tissue is normal, while the mineral content decreased X-ray: bone density decreased; trabecular bone and bone margin blurred.3, bone destruction 4, bone hyperplasia 5, periosteal abnormalities 6, bone and cartilage calcification 7, bone necrosis 8, mineral dep

8、osition 9, bone deformation 10, and surrounding soft tissue lesionsThe basic pathological changes of joint include swelling of joint, destruction of joint, degeneration of joint, ankylosis of joint and dislocation of jointObstructive emphysema: X ray: pulmonary localized opacity increased, mediastin

9、um moved to the contralateral side, and the lateral septum of the disease decreasedObstructive pulmonary atelectasis: X pulmonary density increased evenly, mediastinum moved to affected side, elevated septumPleural lesions: 1, pleural effusion X costophrenic angle blunt, shallow or filled, ipsilater

10、al lung were uniform and dense shadow, sometimes visible biapical transparent and visible rib gap widened, the diaphragm down to the contralateral mediastinal shift2, pneumothorax and liquid pneumothorax; X pneumothorax area without lung texture, gas density, widening of the ipsilateral rib space, t

11、ransverse septum descent, longitudinal to the contralateral side shift3, pleural thickening, adhesion and calcification 4, pleural massBronchiectasis: X regular X ray can show normal, sometimes visible lung markings increased, annular translucent shadow, shadows can be seen in the transparent bronch

12、ial shadow, that is, air bronchus signLobar pneumonia: divided into four stages: hyperemia stage, red liver change phase, gray liver change phase, dissipation phaseClinical: acute onset, chills, high fever, chest pain, rust color can talk aboutX hyperemia period: no obvious manifestation, but only t

13、he lung texture increased. Involving the pulmonary segments were patchy or triangular opacities; affects the lungs, with fissural as large dense shadow; visible air bronchogram and dissipation stage: the size different, irregular patchy shadows, there may be strip shadow, even the machine for organi

14、zing pneumonia.The density decreased gradually in the period of dissipationIn CT, the glass opacity was blurred in the congestion phase, the edge was blurred, and the vessels in the lesion area were still dimly visible. During the period of liver degeneration, dense and dense shadows were observed a

15、long the lobar or pulmonary segments, and there was an air bronchus signLobular pneumonia: clinical: cough, cough phlegm and mucus foam with chest pain, dyspnea and cyanosisThe lesions in the X region are scattered, patchy, blurred, uneven in density, and fused into larger slices. The bronchial wall

16、 is congested and edematous, causing lung markings to increase and become blurredCT: thickening of bronchial vessels, nodular nodules with different sizes and blurred edges. Occasionally, pneumonia, liquefaction, necrosis, cavity formationLung tumors include primary and metastatic tumorsPrimary: Cen

17、tral, peripheral, diffuseCongestion of the lung: obstruction of the arterial system, thickening of the pulmonary hilum, clear margins, pulmonary hilum, dilation of the pulmonary artery, loss of the heart and waist, and pulmonary hypertension, a congenital heart disease that is common in the right sh

18、unt.Pulmonary congestion: obstruction of the venous system, obstruction of the pulmonary hilum, thickening of the hilum, blurring of the margin, dilatation of the upper pulmonary vein, and normal or thinning of the small and lower pulmonary veins.Pulmonary hypertension: common in pulmonary heart dis

19、ease, the main manifestations are: pulmonary artery segment prominent, the hilar area, the east gate of the large branch expansion, the periphery of the sub branch thinning, there is a sudden demarcation between the twoMitral valve type: pear shaped, smaller aortic, pulmonary artery segment fullness

20、 or prominent, the left margin of the heart of the lower round blunt, the heart right edge of the lower segment of the expansion, commonly seen in mitral valve lesions - atrial septal defectAortic type: aortic junction widened, pulmonary artery segment concave, left margin extend to the left, common

21、 in aortic valve disease, hypertensive heart diseaseGeneral: enlarged to the sides of the heart, symmetrical, common in whole heart failure, myocarditisCardiothoracic ratio: 0.05-0.55 was slightly increased; 0.55-0.60 was moderately increased; more than 3.60 was severe increaseThe basic abnormalitie

22、s of tetralogy of Fallot include pulmonary, pulmonary, or valvular stenosis, ventricular septal defect, aortic straddle, and right ventricular hypertrophyAcute abdomen: a group of abdominal diseases characterized by acute abdominal pain, including intestinal obstruction, perforation of the gastroint

23、estinal tract, inflammation, trauma, stones, and gynecological diseasesIntestinal obstruction is generally divided into: loading and unloading of power, and the blood supply of three. Mechanical is divided into simple and narrowTypical signs of intestinal obstruction: flatulence, distension, fluid,

24、gas levelGastrointestinal perforation: X bullying, abdominal fluid, abdominal fat line abnormalities and paralysis of intestinal flatulence are signsThe three impression of the esophagus: from top to bottom: the aortic arch, the impression of the bronchus, the left atrium, and the left atriumFilling

25、 defect: refers to the coating of the outline of the barium, there are localized concave concave performanceNiche: refers to the barium coating contour has the limitation protrusion of the imageKidney: CT round or oval, soft tissue shadow, margin smoothBladder: CT scan, round or oval, bladder urine

26、is homogeneous, watery, low density, bladder wall showed thick, thin, soft tissue density shadow, both inside and outside are smoothThe early bladder wall enhanced scan and delayed scan after 30 minutes, the bladder cavity was uniform and high density, and its wall was whole,Hepatic abscess: X with

27、larger abscess, right diaphragmatic swelling, and hepatic or fluid flat abscess in the liver areaCT scan showed round or round low density areas in the liver parenchyma, abscess in the center, homogeneous or uneven density, CT value higher than water, and lower part of the liver parenchyma, small bu

28、bbles or fluid appeared in the abscessThe plane enhanced abscess wall showed an annular enhancement, with no enhancement of the abscess, and a delayed enhancement of the surrounding edema zoneStem cavernous hemangioma; X artery thickening, huge tumor compression vessels around the curved shift, appe

29、ar holding ball; early artery, tumor edge spots, cotton wool dyeing; venous phase, tumor staining gradually to the central diffusion to achieve uniform CT scan of liver parenchyma in the realm of clear round or round low density mass contrast enhancement in arterial phase, visible tumor edges appear

30、 porphyritic or nodular enhanced in portal venous phase, the density density close to the same layer of large vessels, enhanced mutual fusion, and extended to the central delay tumor; the whole tumor increased from the original unenhanced low density mass into and around the same as normal liver par

31、enchyma density or high density mass, and lasts 10 minutes or longer. The whole process is from the contrast enhancement. CT diagnosis of cavernous hemangioma of liver scan showed 1 state clearly low density lesions, 2 enhancement from the periphery to consolidate, strengthen the density close to th

32、e same layer of large vessel density, and to continue to expand the central 3 long time continued to strengthen, finally with the surrounding normal liver parenchyma into density or high density.Hepatocellular carcinoma: divided into three types: 1, massive mass, diameter greater than or equal to 5c

33、m, the most common;2 nodular hepatic nodules were less than 5cm; diffuse nodules less than 1cm diffusely distributed throughout the liver. 3 small HCC with a diameter of not more than 3cm single nodules, or nodules of less than 3cm and two nodules in diameter, are small hcc. X hepatic arteriography

34、can show the following changes: the expansion of the hepatic artery branch of the blood supply, the pathological vessels in the tumor, the tumor staining, the size of the tumor, the arteriovenous fistula, and the tumor sign. CT scan of liver cirrhosis is common, contour display limitations of projec

35、tions, single or multiple round or oval, clear or fuzzy boundaries of the tumor mass appeared in liver parenchyma, tumors with low density, mhcc necrosis and lower density region; linear density around lower, tumor pseudocapsules. Contrast enhanced multiple phase CT scan: the arterial phase, mainly

36、composed of normal liver parenchyma in portal vein blood has not yet appeared contrast intensity, and to the hepatic artery of the tumor soon appear patchy, nodular enhancement; portal venous phase, normal liver parenchyma increased and the tumor density decreased rapidly; the balance period. Contra

37、st enhanced mass density continues to decline, and in contrast enhancement of the liver parenchyma, and the performance of low density, the contrast is the Kuaijinkuaichu signsLiver metastases: X angiography demonstrates a large, multiple nodule in the study site with pathological vessels and tumor

38、staining and arteriovenous fistulas. The surrounding vessels are compressed and bentUltrasonography: multiple hyperechoic or hypoechoic nodules in the liver.CT scan shows the liver parenchyma of small round or oval low density mass, enhanced arterial phase showed irregular peripheral enhancement, po

39、rtal vein tumor can appear the homogeneous or heterogeneous enhancement, the equilibrium phase contrast enhanced extinction. The central part of the tumor showed low density lesions without enhancement, edge enhancement was high density, constitute a bull eye signCirrhosis: X gastrointestinal barium

40、 meal examination can show esophageal and gastric varices, arteriography shows the branches of hepatic artery become smaller, less and distorted, and the spleen and portal vein dilateCT liver size arrhythmia; liver contour display uneven; hepatic portal, hepatic fissure widenness; and splenomegaly,

41、ascites, gastric and esophageal varicesTraumatic brain injuries include contusion of brain, hematoma of brain, epidural hematoma, subdural hematoma and subarachnoid hemorrhage.Intracerebral hematoma: CT is clearly circular in shape and high in densityEpidural hematoma: cranial plate under spindle sh

42、aped or semicircular high density lesions located near the fracture, across every SkullDie hematoma: acute cranial plate see crescent or half moon high density, subacute or chronic hematoma, slightly high, low, or mixed density rangeSubarachnoid hemorrhage: increased density in the cerebral sulcus a

43、nd cerebral cistern, forming a cast.Astrocytic tumors: grade CT, grade I tumors usually have low density foci with clear boundaries, mild, or no or less intensive effects. Grade II-IV tumors were high, low or mixed density mass with calcification spots and intratumoral hemorrhage, tumor morphology w

44、as irregular, the boundary is not clear, occupying effect and peritumoral edema, which showed irregular ring with mural nodule enhancement, some is uneven enhancementMeningioma: CT scan lesions showed equal or slightly higher density, the more common spots, with wide base and dural connected, round,

45、 clear boundary, peritumoral edema with mild, moderate or severe edema can occur venous or sinus compression. Skull plate invasion caused bone hyperplasia or destruction, enhanced scan uniformity, significantly enhancedRheumatic heart disease: X ray (left atrium enlargement, pulmonary congestion, ri

46、ght ventricular enlargement, pear centroid and cardiothoracic ratio increase)1, mitral stenosis: pulmonary congestion, accompanied by pulmonary edema, heart shaped mitral valve, pulmonary artery segment prominent, left atrium and right ventricle increased.In 2, mitral regurgitation caused by mild re

47、gurgitation, only left atrial and left ventricular enlargement.3, aortic valve insufficiency: the left ventricular increased to varying degrees, left atrium also slightly increased, the middle part of ascending aorta localized expansion.4. Aortic insufficiency: enlargement of the left ventricle, asc

48、ending aorta, and aortic dilatation.Acute pancreatitis: CTPartial or diffuse enlargement of the pancreasPancreatic contour is not clear, around often inflammatory exudation, adjacent prerenal fascial thickeningThe density of the pancreas was slightly decreased and unevenIt can form pseudocyst, with

49、clear boundary and cystic low density shadowAbscesses are localized, with low density foci. Gas is characteristic of abscessesAcute Purulent Osteomyelitis: X rayEarly soft tissue lesions: soft tissue congestion, edemaOsteoporosis 3, bone destruction 4, periosteal hyperplasia 5, bone hyperplasia 6, d

50、ead bone formationChronic suppurative osteomyelitis: X-ray residual bone destruction; bone hyperplasia; dead bone formationPrimary bronchogenic carcinomaThe central type: no special early X-ray manifestations, CT: irregular wall thickening, stenosis, intraluminal nodules in advanced X-ray: the direc

51、t signs of hilar shadow darkening, increased pulmonary hilum mass; indirect signs: emphysema, obstructive pneumonia, atelectasis;In the CT:1 and the air duct masses, the wall of the duct was irregular, the lumen was truncated in the tail of the mouse or truncated by the cup; 2, invasion of the media

52、stinum structures and vessels; and 3, mediastinal lymph node metastasisChildren fracture characteristics: epiphyseal fracture, greenstick fractureFracture complications: delayed union or nonunion, malunion, post-traumatic osteoporosis, joint infection, joint stiffness, degenerative joint disease, os

53、teonecrosis of the bone, myositis ossificansContraposition: the fracture of the end of the fracture occurs either inside or outside the front or back, or up and down, overlapping or separating.On the line: two axis end forming angle of unequal size.The common left and right shunt of congenital heart

54、 disease are atrial septal defect, ventricular septal defect and patent ductus arteriosus.Periosteal triangle: proliferation of different forms of periosteum in malignant tumors, and new bone in hyperplastic periosteum is destroyed by tumor. There is only a small amount of proliferating periosteum a

55、nd bone triangle formed on the edge of tumor.X-ray findings of osteosarcoma: destruction of bone, periosteal proliferation, soft tissue mass, and tumor bone. Osteogenic type: to bone hyperplasia, hardening, uniform ossification shadow, patchy, large range; osteolytic type: the destruction of bone, irregular patchy or large areas of low density, the boundary is not clear, a periosteal triangle formation; mixed type: hyperplasia and the extent of the damage caused by the same big.The X-ray manifestations of esophageal cancer: mucosal folds disappeared, interruption and damage; stenosis, in