What Are the Benefits of a CT Scan for Kidney Stones?

CT examination of the urinary system can not only show the renal pelvis, calyx and bladder cavity, but also diseases such as renal parenchyma and bladder wall.

Name: CT of urinary system

category: Computed tomography computed tomography

CT value of urinary system

Normally enhanced CT of the kidney Normal scan should be performed before enhanced urinary CT scan. The whole kidney should be scanned conventionally in supine position. If you need to observe the ureter and bladder at the same time, expand the scan range and enhance the examination method. Intravenous rapid injection of contrast agent 60--100ml Immediately after completion, scan the two kidney areas at 2min, 5--10min, which is called the three-phase enhanced examination of the kidney. The changes in the degree of renal skin and medullary enhancement and the filling of the kidney and ureter are enhanced. Various reconstructions are possible, including CTU.

The normal kidney cross section is round or oval, the outer edge is smooth, and the middle cross-sectional area of the kidney is the largest. When comparing the size of the two kidneys, attention should be paid to the position of the plane and the direction of the renal axis. The normal renal cortex and medulla density have been constant during the scan, and the normal performance of the three-phase scan of the kidney is as follows: (1) The cortical phase, the density of the renal cortex and renal column increased, and the medulla has not yet strengthened, and the boundary between the two is clear The density of the medulla increases, and the density gradually increases. Eventually, it coincides with the density of the cortex or slightly exceeds the renal cortex. The cortex and medulla boundary gradually disappears. It should be observed to describe the enhancement characteristics of each stage of bilateral kidneys, cortical enhancement, parenchymal enhancement, and pelvic effusion. The focus is on the time and degree of enhancement, and it should be observed on both sides.

Clinical significance of urinary CT

Abnormal results:

(1) Renal dysplasia Congenital renal dysplasia is caused by the failure of the kidney to develop fully due to the development of renal tissue or hind renal ducts and abnormal blood supply during embryonic development. The size of the diseased kidney is significantly reduced, usually only for normal kidneys. 1 / 6--1 / 3, most of them are unilateral, about 3/4 of the ipsilateral adrenal glands are absent, and the contralateral kidneys are mostly compensated for hypertrophy. If both kidneys are underdeveloped, they are usually heavier on one side and have more ureters on the affected side. It is relatively small, and its lower end can be opened at different positions. Enhanced CT scans show that the dysplastic kidneys are smaller overall, the renal cortex and pyelonephrine are reduced in proportion, and the renal arteries and veins are correspondingly thinned. The early strengthening of the renal parenchyma can be reduced compared to the contralateral side, and the contralateral kidney is generally compensated Hypertrophy, should also pay attention to observe other malformations and diseases associated with dysplastic kidneys, such as double pelvis and double ureteral deformities.

(2) Horseshoe kidney The horseshoe kidney is caused by the backlog fusion between the two umbilical arteries of the kidneys of the two sides of the early embryo. The fusion site is mostly in the lower poles of the two kidneys. Sometimes there is only a fibrous band connection, and the connection is mostly located in front of the inferior vena cava and abdominal aorta. The position of the horseshoe kidney is lower than that of the normal kidney. The two kidneys walk down in the longitudinal axis and often have poor rotation. CT manifests as bilateral renal axis transposition, and the lower poles of the kidneys are connected at a lower level by a parenchyma or a cord-like fibrous tissue. CT three-dimensional reconstruction can show the overall appearance of a u-shape. Special attention should be paid to other deformities that may be merged, such as Double or double pelvis and ureter, narrowing of pelvis junction.

(3) Chronic pyelonephritis Chronic pyelonephritis is more common in women than men. The infection is hematogenous and ascending, the latter accounting for 70%. The main pathological manifestations are renal interstitial inflammation and fibrosis. Fibrosis begins in the medulla and occurs first. The scar of the renal papilla retreats, thereby forming a localized or extensive scar contraction of the renal cortex, and the renal pelvis and kidney can shrink or expand accordingly. Pay attention to observe the changes in the shape of the kidney, most of which are reduced, the outline is not smooth, and the disease is unilateral or bilateral, and the local cortex of the kidney becomes thinner, especially during the enhanced scanning cortical enhancement phase. Often, the hydrocephalus is slightly dilated, and sometimes the thinned renal cortex is associated with calcification.

(4) Kidney abscess and perinephric abscess Kidney and perinephric abscess are usually caused by gram-negative bacillus. The initial stage of renal abscess is acute lobular nephritis. The lesion is limited to the renal parenchyma and is cellulitis. As the disease progresses, Lesions can invade inwardly into the renal pelvis and calyces, and can penetrate the renal capsule outwardly, involving back muscle groups around the renal space and psoas muscles. The liquefaction of the lesions develops into renal and perrenal abscesses. The renal and perrenal abscesses can be large or small in size. Perirenal abscesses can exist alone. You should understand the patient's medical history, symptoms of acute infections, pain in the waist and abdomen, and elevated blood image. The characteristics of the lesions should be noted. Plain scans are low-density lesions. Honeycomb changes or large abscesses, enhanced scanning of the cyst wall, especially the inner ring, and interval enhancement. Peri-renal abscesses can invade the peri-renal fat sac. Separately, the lower part can burp, the perifacial fascia thickens, the density of flaky mesh strips in the adjacent fat appears, and the affected side can appear pleural effusion and local intestinal stasis.

(5) Renal tuberculosis Renal tuberculosis is a common disease of the urinary system. It is usually spread from the primary tuberculosis to the kidney through blood. The renal tuberculosis can be roughly divided into pathological renal tuberculosis, early renal tuberculosis, advanced renal tuberculosis, and pathology. Renal tuberculosis does not cause symptoms of the urinary system. Most of them can heal on their own. Early renal tuberculosis can appear painless hematuria. Only in the middle and late stages, when renal parenchymal tuberculosis spreads to the renal pelvis and kidneys, and then the ureter and bladder are involved, typical clinical symptoms appear. ; Urinary system symptoms are urgency, dysuria, hematuria, and even pyuria, systemic fever, fatigue, anemia, weight loss, and so on. CT diagnosis should be performed for those with difficulty in diagnosis, especially for poor imaging of the IVU. CT scan can specifically observe and describe and classify renal tuberculosis: The cavity type of the cheese is low density in the kidney, the edges of the cavity of the cheese necrosis are blurred, and the edge of the dilated kidney is clear. The kidney type of the pus kidney is divided into whole kidneys. It is replaced by a lobular, separated large cystic cavity, and the renal cortex is very thin. The tuberculous form of the tuberculosis is a focal high-density mass with a slightly lower density of cheese necrosis area. For example, the thickening of the renal pelvis wall, the thickening of the renal pelvis, the extensive thickening of the ureteral wall, and the condition of bladder tuberculosis inflammatory contracture, CT reconstruction shows a better effect on the lesion.

(6) Renal cysts Simple renal cysts originate from the renal tubules and have a wall thickness of 1--2 mm. They occur mostly on the surface of unilateral renal parenchyma. They can also be located in the deep cortex or medulla, but they are not connected to the renal pelvis and calves. The cysts gradually expand and can compress adjacent normal tissues. The cysts vary in size. The cystic fluid is serous and 5% is bloody. In addition to the water content of the cystic fluid, there are still glucose, a small amount of protein, lipids, cholesterol and chloride. Calcium salts can be deposited, and infections, stones, and tumors can occur. The plain scan of renal cysts shows single or multiple round low-density foci. Generally, the density is uniform and the sizes are different. The enhanced CT scan has clearer borders, no walls or thin walls. Care should be taken to describe the location, size, number, and size of cystic lesions. The diameter of large lesions should be measured. Pay attention to the characteristics of thin or no walls and no strengthening. The density of cystic fluid is high during plain scan, which may be accompanied by bleeding or infection. The cystic wall can be linearly calcified.

(7) Renal vascular smooth muscle lipoma Angioleiomyomatoma is the most common benign tumor of the kidney. It is single or multiple, and it occurs in middle age. It is more common in women. The tumor originates from the mesoderm and is composed of smooth muscle, fat and abnormal blood vessels. Their content varies greatly, most of them are mainly composed of fat components, and a few are mainly smooth muscles. They are swollen and grow. The tumor vessel wall lacks elastic fibers, which often causes bleeding in the tumor or around the kidneys, causing hematuria and renal vascular smooth muscle fat. 20% of tumors have nodular sclerosis. The most important feature of CT is the fat component in the tumor. The ct value is negative, and the substantial part of the enhanced scan is moderately enhanced. The tortuous deformed blood vessels in larger tumors are significantly strengthened during enhanced scanning. Generally, there is bleeding or hematoma in the tumor or tumor edge, and the density of the plain scan is high. Care should be taken to describe and describe the number, size, and extent of perinephric invasion of smaller tumors. For smaller tumors, attention should be paid to the characteristics of benign and non-invasive tumors: cleavage signs and cup-mouth signs formed by the normal renal cortex of the tumor margins.

(8) Renal cancer Renal cancer is the most common parenchymal tumor of the kidney. It is derived from renal tubular epithelial cells, mostly unilateral and originates at the pole of the kidney. Kidney cancer is mostly round, with oppressed renal parenchyma and fibers. The pseudocapsule formed by the tissue has a hard texture, most of which are accompanied by fibrotic plaques or calcifications, and there may be bleeding, necrosis, and cystic changes. Most renal cell carcinomas are clear cell carcinomas, which can destroy all kidneys and can directly invade. Adjacent tissues and organs can also grow into the kidney and involve the renal pelvis and pelvis, which can form renal veins and inferior vena cava tumor plugs. The characteristics of CT are: changes in the shape of the kidney, prominent limitations or overall enlargement masses on plain scan can be equal, slightly lower or higher density, tumor necrosis, lower density of cystic areas, and density of calcified and bleeding areas Increased Enhanced scan. The arterial tumors are significantly strengthened but uneven. The density of the parenchyma and pelvis is generally reduced, and the realm is clearer. This fashion can observe the invasion and destruction of the renal pelvis and pelvis, and special attention should be paid to the range of perinephric invasion of the tumor. And lymph node metastasis, renal vein and inferior vena cava tumor thrombus were observed in the parenchymal phase, and finally CT staging of renal cancer should be performed.

(9) Renal pelvis cancer Renal pelvis cancer is a malignant tumor of the renal pelvis or sacral mucosa, which is mostly transitional epithelial cancer. 8% of the cases of ureteral and bladder cancer are diagnosed earlier than renal pelvic cancer. Squamous cell carcinoma accounts for approximately 7%, mostly due to calculus, inflammation, etc., stimulate the transitional epithelium to metastasize and cause tumors. It has a high degree of malignancy and easily invades the surrounding pelvis, kidneys, ureters, and even the renal parenchyma. Adenocarcinoma is a rare type. The degree of malignancy is high, and distant metastasis can occur earlier. Renal pelvis cancer has the following two types of changes. CT should pay attention to observe its different characteristics. The intrarenal type is characterized by a soft tissue mass at the renal pelvis, the narrowing or disappearance of the fat gap in the sinusoidal sinus, often accompanied by renal pelvis dilatation and hydronephrosis. The mass is moderately strengthened. The renal pelvis during the pelvic imaging period shows a filling defect in the pelvis, the pelvic wall infiltrates as the renal pelvis, and the irregular thickening or flattened masses adjacent to the ureteral wall can be strengthened. At the same time, the renal parenchymal invasion should be observed and described. The report should also mention whether Ureteral bladder implantation, large-scale scanning, and CT reconstruction show good changes in tumor range and secondary hydronephrosis, which should be taken seriously and described.

(10) Kidney stones Calcium oxalate, calcium phosphate is positive stones, uric acid stones are negative stones, urinary stones occur in 35--50 years old, causing obstruction, injury and infection of the renal pelvis and calves. Obstruction and symptoms are not severe if the stones are less active. Plain CT scans are mainly high-density calcifications of positive stones in the renal pelvis and calyces. A few positive stones can be located in the renal parenchyma, mainly small stones in the renal tubules in the medullary region. The high density in the renal pelvis or pelvis should be observed and described. The size and number of shadows, pay attention to the combined pelvic pelvic effusion and the reduction of renal perfusion, combined with CT reconstruction and IVU to observe the presence of primary obstructive lesions, to determine the possibility of secondary stones, for combined pelvic inflammation, Incarcerated stones at the junction of the pelvis and renal medulla should also be noted.

(11) Ureteral stones Urinary stones are the most common in urinary stones. Most of them come from the lower kidney. Pathological changes of the ureter caused by stones are mainly mucosal bleeding, edema, infection, ureteritis, periureteritis, and stone obstruction. Causes different degrees of hydronephrosis, which can damage the renal parenchyma. Most of the stones stay in the physiological stenosis. Stones with a diameter of 1cm often stop at the junction of the renal pelvis, and stones with a diameter of less than 5mm usually stop at the bladder entrance or above. 2--3cm. The main symptoms caused by ureteral stones are pain and hematuria. If colic occurs, it is more typical, more severe, and the direction of radiation is more severe than colic in kidney stones. Plain CT scans are mainly high-density calcifications of positive stones in the ureteral walking area. When ureteral stones are suspected, a wide-range scan or localization based on recent ultrasound or IVU should be used. The obstructed area should be observed downwards along the ureter with a swollen ureter. Visible high-density shadows in the ureteral cavity and peripheral signs of ureteral edema formation. Multi-layer spiral CT curved surface reconstruction can show the site of ureteral calculi, secondary dilatation of the upper urinary tract hydrocephalus, and ureteric wall inflammatory thickening.

(12) Ureteral cancer. The majority of ureteral cancers are transitional cell carcinomas. They occur in the lower ureter. Squamous carcinomas are rare and show invasive growth. They often invade all layers of the ureter. They spread early and extensively. Adenocarcinoma is more rare and ureteral cancer. It can infiltrate and spread to the surrounding ureteral tissues or transfer to adjacent lymph nodes, and it can also be transferred to distant places through blood or lymph circulation. Among them, liver metastasis is the most common. The ratio of male to female is 2: 1, and the average age of onset is 60. It is the most common. The symptoms of hematuria are ureteral obstruction caused by cancer, which often results in hydronephrosis. CT features are: Different degrees of hydronephrosis of the renal pelvis and ureter. Continuous observation of all levels can find intraluminal masses at the ureteral obstruction end, invasion of extraluminal masses, uneven thickening of the ureteral ring, etc. Enhanced scanning, especially the arterial The mass or limited thickening of the ureter can be significantly strengthened. The delayed period shows the filling defect in the official cavity. You should pay attention to observe the size of the mass and whether it invades outside the cavity. At the same time, you should observe whether there are tumor lesions in the renal pelvis and bladder during a large-scale scan. CT surface reconstruction can show the tumor itself and secondary obstruction hydronephrosis comprehensively and intuitively. The report should describe the above situation.

(13) Bladder cancer Bladder cancer accounts for about 1% -3% of the total number of malignant tumors in the whole body. There are more men than women. Bladder cancer is pathologically divided into papillary cancer and non-papillary cancer. The former comes from the epithelial cells of the bladder mucosa. 90% -95%, the latter is a minority, such as squamous cell carcinoma and adenocarcinoma, bladder cancer of all epithelial cells has multiple, recurrent tendency, the main clinical manifestation of bladder cancer is non-specific, recurrent macroscopic Hematuria and CT can detect the extent and extent of early bladder cancer and tumor invasion, and can better show the invasion of adjacent structures by tumors and the presence or absence of lymph node metastasis, and can be used for tumor staging. CT scan of bladder cancer usually shows a medium-density mass protruding into the bladder cavity. The contrast injection is significantly enhanced. The tumor has pedicles, no pedicles or plaque-like growth, and some only see localized bladder wall thickening and larger tumors. Due to necrosis, liquefaction makes the density uneven; when the tumor invades the fat layer around the bladder, the outer wall of the bladder is blurred, and a strip-like density increase appears in the fat layer. The staging principle of bladder cancer is: T1 tumors are limited to the mucosa and T2 Tumor invasion and superficial muscle layer; t3a stage tumor invades and deep muscle layer but does not invade surrounding tissue of the bladder; t3b stage tumor penetrates the muscular layer to involve tissue around the bladder; T4a stage involves adjacent organs; t4b stage involves pelvic cavity. However, CT has limited staging before T3b. Pay attention to observe and describe the size, number and location of bladder cancer masses, determine the extent and extent of tumor invasion, whether there is invasion of adjacent structures and whether there is lymph node metastasis, and staging, pay attention to tumor invasion The condition of the bladder ureter entrance, and at the same time observe the presence of tumor lesions in the lower ureter and secondary dilatation of the upper urinary tract.

(14) Adrenal hyperplasia Adrenal hyperplasia is often caused by hypothalamic pituitary dysfunction or excessive pituitary tumor secretion of ACTH. A few are caused by ectopic ACTH syndrome, but in the aldosteronism, adrenal hyperplasia accounts for only 20%. And 80% is caused by aldosterone adenoma. Adrenal hyperplasia can be divided into general thickening type and large nodular type, often bilateral. The thickness of the medial and lateral branches of the normal adrenal gland on the CT cross section is uniform and does not exceed the thickness of the ipsilateral iliac muscle foot on the ipsilateral side, which is concave. Some normal adrenal glands are larger and dense, but the width is <1 cm. During adrenal hyperplasia, the adrenal glands bulge outward, often exceeding the ipsilateral diaphragmatic foot, and some show limited round or oval nodules. However, about 50% of Cushing's syndrome should be noted. CT shows normal adrenal glands, so it should be combined with Clinically relevant biochemical examination. Adrenal hyperplasia can be divided into general type and giant nodular type. Attention should be paid to the identification of nodular hyperplasia and adenoma. Generally speaking, bilateral nodules, multiple unilateral nodules with general thickening of the adrenal glands should be diagnosed as hyperplasia.

(15) Adrenocortical adenoma Adrenocortical adenoma accounts for 15% -20% of Cushing's syndrome. Generally, the onset is slow. It is usually single. Adults and men are more common. Most are round or oval. The diameter is mostly 2--3cm, uniform texture, intact capsule, little bleeding or necrosis, high-functioning adenomas are usually small and detected, and non-functioning adenomas can be very large. CT manifestations are nodules or masses of different sizes in the adrenal gland. The different characteristics of some adenomas should be observed and described as follows: Aldosterone adenomas are often less than 1 cm in diameter, and they are uniformly low density, half of which are negative. No enhancement Cortisol adenoma patients have a large amount of fat deposits retroperitoneally. The tumor has a uniform and medium density, and the outline is smooth. After enhancement, it is slightly strengthened uniformly. A few tumors contain more lipids and have a low density. The contralateral adrenal glands or ipsilateral Residual adrenal glands may have atrophy. Non-functional adenomas are generally large, and clinically there are no endocrine symptoms.

(16) Pheochromocytoma The main clinical manifestations of pheochromocytoma are paroxysmal hypertension, a few of which have no hypertension, more than 90% occur in the adrenal medulla, and a few occur in the adrenal diplomatic ganglion chain; about 10% are double Lateral or multiple; 10% are malignant, occasionally ectopic can occur in the bladder and other places. Pheochromocytomas are usually large, with an average diameter of 5--6 cm, and most of the edges are clearer and smoother. The smaller tumors have a uniform density, and the larger ones often have cystic changes. Care should be taken to describe and describe the tumor margins and density. There are cystic changes and hemorrhages. The enhanced scan is often significantly enhanced but the cystic area is not enhanced. Note that the mass is large, the edges are irregular, and the invasion of adjacent organs indicates malignant changes. If the clinical symptoms are typical and there is no mass in the adrenal region, the retroperitoneum and Ectopic pheochromocytoma in other areas such as the bladder. Huge pheochromocytoma, CT is easy to mistake the liver as a lesion. Pay attention to the linear low-density space between the mass and the liver, and separate the lower mass from the liver. Coronary and sagittal reconstruction can be further identified.

(17) Adrenal neuroblastoma Adrenal neuroblastoma is a tumor that is more common in children, especially in children under 4 years of age. The tumor can occur in the adrenal medulla, but also in the chest, abdominal sympathetic nerve chain, or peripheral sympathetic nerves. Children often see a large abdominal mass, and tumor calcification is more characteristic. Adrenal neuroblastoma CT features: The mass is often large, the density is often uneven, can grow beyond the midline, common calcified plaques with diagnostic features, CT coronary and sagittal reconstruction can show that the tumor is separated from the kidney, pay attention to observe and describe the vicinity Whether blood vessels have been invaded and whether tumors have invaded the spinal canal.

(18) Prostatic hypertrophy Prostate hypertrophy, also known as benign prostatic hyperplasia, is one of the common diseases of older men. Testosterone and aging are two conditions for the occurrence of bph, which is also related to chronic prostatitis. bph originates from glands and transitional glands around the urethra of the prostate. When the prostate is enlarged, the internal pressure and resistance of the urethra increase, which gradually causes mechanical and dynamic obstruction of the bladder outlet. At the same time, the internal pressure of the bladder increases, and the end of the ureter loses its valve function. Bladder ureteral reflux, obstruction and reflux cause hydronephrosis and renal function damage, which can be complicated by stones and infection. The normal upper bound of the prostate does not exceed 10mm above the pubic symphysis, and the enlarged upper bound of the prostate exceeds 20mm above the pubic symphysis. Generally, the upper bound of the prostate is spherical, symmetrical, smooth edges, uniform density, enhanced scanning arteries, and the central area of the venous phase is diffuse. Uniform strengthening, not strengthening in the peripheral area, sometimes the anterior part of the lateral glands of the gland shows a bilobal symmetry protruding forward with the median sulcus as the boundary, increasing the pressure of the prostate or protruding into the lower part of the bladder, but the bladder is intact and the edges are smooth. It should be observed Measure and describe the size of the prostate. Chronic patients, especially those with urinary retention, should observe and describe bladder inflammation and pseudoventricular changes, or even bilateral upper urinary tract hydrocephalus dilatation.

(19) Prostate cancer Prostate cancer is one of the most common male tumors. Its incidence is second only to lung cancer, and it is the second leading cause of cancer death in men. Prostate cancer often occurs in the surrounding area of the prostate, and it is primary in the transitional area. Often accompanied by bph, the metastatic pathways of prostate cancer include direct infiltration, hematogenous metastasis, and lymphatic metastasis, which can invade the urethra, seminal vesicles, bladder, and bone metastases. The most common hematogenous dissemination is the pelvis, lumbar spine, and femur. Thoracic spine, ribs are often osteogenic metastases. Plain CT scans show increased prostate density unevenness or low-density nodules, or nodules around the prostate. Enhanced arterial cancer nodules are generally not significantly enhanced, and venous cancer nodules are equally low density. Attention should be paid to this period of observation. In order to stage prostate cancer, attention should be paid to describing and describing the fatty layer around the prostate, seminal vesicles, bladder, pelvic floor muscles, lymph nodes, and pelvic and lumbar metastases. (20) Uterine leiomyomas Uterine leiomyomas occur in women aged 30--50 years. They are divided into submucosal type, intermuscular type, and subserosal type according to the growth site. Most patients have menstrual changes and manifest themselves as menstrual changes. Large amount, long duration, short interval, common to submucosal fibroids and larger intermural fibroids. Subserosal fibroids can be without menstrual changes. Pathologically, uterine fibroids are composed of smooth muscle tissue and a small amount of fibrous tissue. Fibroids themselves do not have an envelope, and the compressed uterine muscle wall tissue around the fibroid forms a false envelope. On CT, different types of uterine fibroids have different characteristics. The uterine fibroids of the uterine fibroids between the muscle walls become narrower and offset; the subserosal fibroids grow out of the uterus and are connected to the uterus with narrow pedicles; Narrow, plain scan masses are generally not very clear, showing a more uniform and equal density, which can be accompanied by calcification, enhanced scans are significantly enhanced, the realm is clear, cystic deformation and necrotic areas are not strengthened, the report should first describe the enlargement of the uterus and contour changes, specific lump attention The above-mentioned characteristics should be reflected, and the number, size and location of tumors should be described.

(21) Cervical cancer Cervical cancer is the third leading cause of death among gynecological malignancies. The average age of onset is about 50 years old, and it shows a bimodal distribution around 35 and 60 years. Cervical cancer is the most common The clinical symptoms are vaginal bleeding and vaginal drainage. Other non-specific symptoms are frequent urination, difficulty urinating, pelvic pain, constipation, and blood in the stool. The further development of the disease course can cause corresponding symptoms such as urinary tract or intestinal obstruction. CT can stage cervical cancer, evaluate prognosis and review after treatment. CT manifestations of cervical enlargement, parenchymal masses> 3.5cm in diameter are of diagnostic significance. Necrosis in the masses appears as irregular low-density areas. Special attention should be paid to cervical cancer invasion of the uterus, parauterine tissue, pelvic lymph nodes, bladder and rectum. Description, should understand that the main purpose of CT examination is the staging of cervical cancer and whether there is recurrence after surgery or radiotherapy.

(22) Ovarian cystadenoma Ovarian cystadenoma is divided into serous cystadenoma and mucinous cystadenoma, which accounts for about 1/4 of the primary ovarian tumor. The bilateral incidence is 15%. Mucinous cystadenoma can coexist, and serous cystadenoma changes in a single room or multiple rooms. Mucinous cystadenoma often changes in multiple rooms. The age of onset is 20--50 years. Clinical symptoms include abdominal discomfort or dull pain, abdominal masses, etc. A small number of patients with menstrual disorders may have ascites, pathological manifestations, the tumor section is cystic, single or multilocular, and the cyst wall is smooth or has Papillary processes, serous cystadenoma cyst wall epithelium single-layer cubic or short columnar epithelium, mucinous cystadenoma cyst wall epithelium is a single layer of mucous columnar epithelium. CT features are: unicompartmental serous cystadenoma is generally large, the cyst wall can be locally thickened, there can be short spaces, wall nodules and cystic calcification; mucinous cystadenoma is also often large, showing multiple rooms Sexual, internal linear separation, generally the density of fluid in a mucinous cystadenomas is higher than that of serous cystadenomas. The morphology, size, and density of pelvic cysts should be observed and described. It should be distinguished from encapsulating effusions and dermoid cysts.

(23) Ovarian cancer Among female malignant tumors of the reproductive system, the incidence of ovarian cancer is second only to cervical cancer. In most patients, most patients are asymptomatic or have mild symptoms in the early stage. At the time of consultation, extensive pelvic metastasis has often occurred. Ovarian cancer originates from epithelium. Its tissue types are diverse, of which serous cystadenocarcinoma accounts for a large proportion, accounting for about 42%. Tumor dissemination is mainly through tumor surface cell seeding and lymphatic metastasis, and hematogenous dissemination is rare. CT showed pelvic cavity or lower abdomen of varying sizes, irregular solid or cystic solid masses, and serous cystic adenocarcinoma with calcified lesions. Attention should be paid to describing the size, shape and location of cystic solid or solid masses. Multi-level and multi-dimensional reconstruction images can observe the relationship between tumors and ovarian attachments. Others should pay attention to the appearance of ascites, omental peritoneum and retroperitoneal lymph nodes. Metastases, liver metastases, and intraperitoneal implant metastases, especially the peritoneal pseudomyxoma, are the cystic lesions of ovarian mucinous adenocarcinoma that rupture into the peritoneal cavity and can reach the outer edge of the liver and spleen. People to be examined: Patients with lesions in the renal pelvis, calyx, bladder cavity, renal parenchyma, bladder wall and other parts.

Precautions for CT examination of urinary system

Unsuitable people: (1) People with allergies or history of allergies with ionic contrast agents (if using ionic contrast agents, iodine allergy test is required). (2) People with heart, lung, liver and kidney insufficiency. Note before examination: (1) The detailed medical history and various examination results must be notified to the CT doctor before the examination. If you keep the X-rays, magnetic resonance films and previous CT films, you should give them to the CT doctor for reference. (2) Tell your doctor if you have a drug allergy or if you have allergic diseases such as asthma or urticaria. (3) The clothing to be removed from the inspection site includes underwear with metal substances and various items: headgear, hair clips, earrings, necklaces, jade pendants, coins, belts and keys. (4) For CT enhanced scans or children, unconscious, accompanied by a healthy person. (5) For CT enhanced scans, if an ionic contrast agent is used, an intravenous contrast agent iodine hypersensitivity test is required. After 20 minutes, there is no response before examination. (6) Do not take medicines containing heavy metals for 1 week, and do not perform gastrointestinal barium examination. Patients who have undergone a barium test should wait for the barium to be emptied; those who are anxious for a CT test should give a clean enema or oral laxative to make the barium complete before the CT test. Requirements during the inspection: (1) The inspection process should be performed in accordance with the doctor's password. Do not randomly move to ensure the clarity of the radiography. (2) There is a walkie-talkie on the CT machine. If there is any discomfort or abnormal situation during the inspection, the doctor should be informed immediately.

CT examination of urinary system

One, kidney

No special preparation is required for renal CT scans. The upper bound of the scanning range should be slightly higher than the upper pole of the kidney, and the lower pole is to the lower pole of the kidney. Oral contrast agents are generally not required. Except for suspected kidney stones and contrast agent hypersensitivity and renal insufficiency, enhanced scans should be routinely performed. Intravenous injection showed renal arteries, veins, and renal parenchyma with good results. The renal pelvis usually develops about 2 minutes after the contrast injection. MRI generally uses cross-section and coronal or sagittal plane, spin echo T1WI to show the anatomical structure and then cross-section T2WI to determine the nature of the lesion. On the cross-section CT image of the kidney, there are round or oval soft tissue shadows with clear edges and smooth outlines. The hilar region is invaded, and renal arteries, veins, and ureters enter and exit. During plain scan, the renal parenchymal density was uniform, and the cortex and medulla could not be distinguished. The CT value was 30-50Hu. When the diuretic effect is strong, the density decreases, only about 15Hu. With enhanced scanning, the renal parenchymal density increased, and the CT value reached 80-120Hu. When the renal pelvis and calamus were scanned plainly, the density was watery, and the enhanced scan density was significantly increased. The size of the renal pelvis is variable. The ureteral plain scan was spot-shaped, with enhanced scanning density and easy to identify. The renal fascia can be developed in 50% of cases, and it is a dense thin line-shaped shadow. (1) CT of kidney tumors is quite accurate in showing renal cancer and pelvic cancer. The size of the tumor, the extent of invasion, and metastasis of adjacent and distant lymph nodes can also be determined, which can help staging. CT scan of renal cancer shows a mass with a density lower than or equal to that of the renal parenchyma, and sometimes a slightly higher density. The edge of the tumor is smooth or irregular, and the boundary between the tumor and the parenchyma is unclear, and it can protrude outside the kidney. Tumor necrosis or sacs become low-density areas, while calcification and bleeding are high-density areas. On enhanced scans, abnormal blood vessels and tumor enhancement were seen in the polyangioma. The tumor vessels and enhancement disappeared half a minute after injection, while the renal parenchyma strengthened, the tumor showed a low density. Less vascular cancer is not strengthened. Enhanced CT scan of renal pelvis cancer showed filling defect in the renal pelvis. Its CT value and morphology can help exclude fresh blood clots, cysts and stones. A mass that infiltrates the renal parenchyma needs to be distinguished from renal cancer. Tumors often deform the sinus and occlude normal sinus fat. Because the tumor can be metastasized to the ureter or bladder, a CT scan should include the ureter and bladder. Small calcium spots were occasionally seen in the tumor. (2) CT diagnosis of renal cyst is quite reliable. Renal cysts were found in living organisms after CT. A plain scan shows a round or quasi-round shape in the renal capsule, with smooth edges, uniform density, and water-like density. Enhanced scanning without enhancement. Typical performance, not difficult to diagnose. The capsule wall can be calcified. Sometimes the cyst density is high or the cyst wall is thick, which needs to be distinguished from tumor necrosis and abscess. Polycystic kidney scan revealed that the two kidneys were enlarged, showing a leaf-like shape with multiple cysts inside, ranging in size and thin walls. Calcification was seen in the renal parenchyma. Cysts of the liver, pancreas and spleen can also be found. More plain scans can confirm the diagnosis. (3) When hydronephrosis is lost, imaging cannot be performed on IVP, and CT is easy to display. It can be seen that the renal pelvis and calyces are enlarged, the renal shadow is enlarged, and the renal parenchyma is thinner in severe cases. Upon enhanced examination, the renal parenchymal density was lower than normal. If the contralateral side is normal, it is easier to distinguish. When ureteral insufficiency or early in the obstruction, after injection of contrast agent, it can be seen that urine without contrast agent forms an interface with contrast agent. CT can not confirm the diagnosis of hydronephrosis, and it may be possible to determine the etiology. MRI can also be displayed. The difference of renal cortex and medulla became insignificant in patients with poor renal function. (4) Positive stones for kidney and ureteral stones are easy to find by plain scan. They are high-density shadows of different sizes and shapes in the kidney and ureter. Negative stones are also high-density shadows. When filling defects are found on the IVP and it is difficult to judge negative stones, blood clots, and renal pelvis cancer, CT is of differentiating significance. Stones or calcifications have lower MRI value. (5) CT and MRI diagnosis of renal trauma and staging. Can show incomplete renal parenchyma and intrarenal hematoma, complete renal laceration, renal detachment, subcapsular hematoma, perinephric space or other retroperitoneal space hematoma, fresh bleeding, CT plain scan showed increased local density. Hematoma liquefies, reducing its density. On enhanced scans, the density of hemorrhagic or hematoma areas within the renal parenchyma is often lower than the density of enhanced normal renal parenchyma. The renal pelvis may be poorly filled with blood clots. MRI can better show the bleeding and evaluate the stage of bleeding. (6) Nephritis Acute renal infections, such as renal abscesses, plain CT scans can show lesions that are slightly less dense than normal renal parenchyma, but the kidney enlargement is not significant. The edges of the enhanced scan are clear and the density is low. The inner side is the abscess wall, which is thick and may be uneven. The abscess center is not enhanced, and it is a necrotic and liquefied area. Generally small, about 1-2cm in diameter. It needs to be distinguished from renal cysts or tumors, and the diagnosis is not difficult in combination with history and clinical manifestations. MRI is similar to CT in morphology. Renal tuberculosis is a chronic inflammation. Early CT scans have minor changes and are easy to ignore. Hydronephrosis, abscess, and renal parenchymal atrophy can be seen in the advanced stage.

Adrenal glands

Adrenal CT scans do not require special preparation. Short scan times, thin slices, and magnified scans are better for showing the adrenal glands and their lesions, including the planes above the adrenal pole to the hilum. No oral preparations are required. Enhanced scanning can help observe the vascular structure in the tumor and determine the presence or absence of liver metastases. A CT image of the adrenal gland cross-section was normally inverted V-shaped, inverted Y-shaped, triangular or linear, with the cuspid anterior and posterior extension of the inner and outer limbs. The edges are smooth without nodular outlines. Enhanced scanning is uniformly enhanced. (1) Pheochromocytoma Pheochromocytoma comes from adrenal medulla pheochromocytoma. Tumors are often larger than 2 cm in diameter and can be detected by CT. Since 10% -15% can occur outside the adrenal gland, if no adrenal tumor is found, scan other parts, especially the abdomen. The tumors are bilateral in 10% of adults and 20% of children. The clinical manifestations are mainly paroxysmal or persistent hypertension, with episodes of blood remission after a few minutes to several hours. CT showed a mass with clear edges, uniform density, and a diameter of 2-4 cm. Intratumoral necrosis is characterized by low density and calcification. Enhanced scan shows enhancement. 10% -15% of pheochromocytomas are malignant, and the tumors are large. It is difficult to distinguish benign or malignant tumors by CT. However, malignant lymph node metastases, infiltration of adjacent tissues, and liver metastases can be diagnosed. (2) Adrenocortical adenoma Adrenocortical adenoma CT shows smooth, round, or oval tumors with uniform density, equal to or lower than the density of the kidney. Enhanced scans are uniformly enhanced. Contralateral adrenal atrophy is smaller but normal. Adrenocortical tumors are divided into primary hyperaldosteronism and hypercortisol due to the different properties of the secreted hormones. The former adenoma is smaller. About 0.5-0.3cm. The latter have larger adenomas, about 2-8 cm. All showed round or oval masses. The former, because the tumor is small, often involves only a certain portion of the adrenal glands. In addition to adenomas, the two functional abnormalities can also be caused by the corresponding adrenal hyperplasia. (3) Adrenal hyperplasia and atrophic adrenal hyperplasia. CT shows enlarged adrenal glands on both sides, full outline, or multiple nodules. However, it is not uncommon for the adrenal glands to be normal in size and shape. Chronic adrenal insufficiency, Addison disease. Mostly caused by idiopathic adrenal atrophy due to autoimmune abnormalities. Also seen in tuberculosis, amyloidosis and bilateral adrenal metastases. CT showed small adrenal atrophy on both sides. Adrenal calcification can be seen in tuberculosis patients.

Third, the bladder and prostate

Both CT and MRI are suitable for diagnosis of bladder and prostate diseases. However, MRI is better than CT for showing the invasion of lesions to organs adjacent to adipose tissue, and for showing the internal tissue structure of the prostate, such as the central and peripheral regions and the transitional region. Therefore, MRI is better for the diagnosis of bladder and prostate diseases. CT examination of the bladder requires full inflation to distinguish the bladder wall from the lumen. Drinking more water and not urinating to inflate the bladder is simple, but not accurate enough. Inflation of the bladder with low-concentration iodine, normal saline, air, or CO2 gas through the urethral cannula is likely to show lesions. A cross-section scan was performed routinely, from the pubic symphysis to the upper edge of the pelvis, with a layer thickness of 1 cm. Tumors at the top or bottom of the bladder or prostate cancer that invade the bottom of the bladder are best reconstructed with a coronal. Enhanced scanning can make the ureter develop and help to identify enlarged lymph nodes, but scan the bladder early in the bladder filling contrast agent, because too late, the contrast agent in the bladder is too thick and prone to artifacts. (1) CT diagnosis of bladder cancer is simple and accurate. It can be seen that the soft tissue mass protruding from the bladder wall into the bladder cavity can also infiltrate into the wall, showing a local thickening. Infiltration of adjacent tissues and lymph node metastases can also be detected by CT. Therefore, CT is helpful for staging of bladder cancer. (2) Prostate hypertrophy and prostate cancer The size of the prostate is related to age, but generally its diameter does not exceed 5 cm. Prostate hypertrophy can be seen, the prostate into the bladder bottom. The edges are smooth and the density is uniform. Generally, the two sides are symmetrical, and the hypertrophy is obvious on one side. The coronal plane is displayed more clearly. CT is difficult to diagnose when prostate cancer grows within the capsule, and it is only possible to diagnose when the capsule has penetrated into the surrounding adipose tissue. Appeared as uneven prostate contour, uneven density. The anterior rectum wall and bladder wall can be infiltrated and the seminal vesicle angle disappears. CT can also detect lymph node metastases and pelvic metastases. CT is helpful for staging of prostate cancer.

Diseases related to CT of urinary system

Egyptian schistosomiasis, kidney stones, bladder cancer, male urethral cancer, prostate cancer, kidney cysts, urinary tract infections, kidney and ureteral stones, renal tuberculosis, cystitis