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1.
Emission computed tomography is a new, useful imaging technique; when a rotating gamma camera capable of such imaging is used multiple adjacent transverse sections may be obtained simultaneously, from which coronal and sagittal sections may be computed. The technique was used in a man undergoing urological investigation in whom excretion urography indicated a space-occupying lesion in the left kidney. Ultrasonography and radionuclide imaging showed nothing abnormal, but emission computed tomography using a rotating gamma camera showed that functioning cortical tissue extended across the middle of the left kidney. Radiographs were therefore reviewed and ultrasonography repeated, and it was concluded that the abnormality was a hypertrophied column of Bertin. Emission tomographic imaging of the kidney is a useful adjunct to other non-invasive studies.  相似文献   

2.
Isotope examination of the liver depends on the functional activity of the liver phagocytes, while ultrasound and CT scanning display the anatomical structure. Cold areas on an isotope scan may be due to impaired function or space-occupying lesions. The method is nonspecific and does not differentiate between cysts, abscesses and metastases. Both ultrasound and CT scanning can differentiate space-occupying lesions with a high degree of accuracy so that both techniques can be used to improve the accuracy and specificity of the radioisotope examination. CT scanning of the liver is limited by relatively slow data acquisition and the small differences in X-ray absorption within soft tissues unless contrast agents are used. In comparison, ultrasonic data are rapidly collected and displayed and liver consistency is imaged without contrast media or ionizing radiation. Diffuse abnormalities of the liver, such as cirrhosis, cannot be detected by CT scanning but are apparent on ultrasound examination. In addition, equipment purchase and maintenance costs for ultrasound are a fraction of those for CT scanning. Experience to date at Yale indicates that ultrasound and CT scanning are complementary and supplementary to isotope examination of the liver but that ultrasound in most patients produces better resolution and enhanced tissue differentiation at considerably less cost.  相似文献   

3.
The order of radio- and ultrasound diagnosis in the filling defects of the renal calyceal-pelvic systems, resulting from radionegative concrements, "vascular imprints", papillary tumors, and renal tumors affecting the calyceal-pelvic system, should be as follows: excretory urography, ultrasound scanning of the kidneys, retrograde pyelography with a double contrast study (a patient in a vertical posture), and angiography. Reliable diagnostic information obtained at the 1st or 2nd stages of investigation, permits the use of less invasive methods like excretory urography and ultrasound scanning. Retrograde pyelography with a double contrast study is recommended in a suspected pelvic papillary tumor. Angiography is indicated for suspected pathological vascular changes and for a planned operation.  相似文献   

4.
Emission computed tomography (emission CT) and conventional planar gamma-camera imaging of the liver were compared in 242 patients with suspected metastatic spread to liver. Concordant data were obtained in 171 patients (71%). Single large lesions, multiple small lesions, and diffuse disease were accurately defined with this new radionuclide tomographic technique. The smallest lesion detected by emission CT was 8 mm. Emission CT, planar gamma-camera imaging, and transmission (x-ray) CT were compared in 107 patients. All three methods gave identical results in 76 patients (71%). Assessed against other criteria, such as histological findings and follow-up data, emission CT yielded the highest range of accuracy (92-96%), while transmission CT and planar gamma-camera imaging had similar but lower accuracies (78-81%). Emission CT had a false-positive rate of 2.8% and a false-negative rate of less than 1%. Thus emission CT is highly sensitive in detecting space-occupying disease in the liver.  相似文献   

5.
Selective venous sampling was performed in 31 patients in whom the diagnosis of phaeochromocytoma was suspected on clinical and biochemical grounds. Data from samples assayed for their adrenaline and noradrenaline content using a radioenzymatic technique were used to confirm or refute the suspected diagnosis. In 19 of the 31 patients a phaeochromocytoma was subsequently removed surgically, and the remaining 12 patients are now thought not to have tumours (mean follow up period: four years). Analysis of the assay data shows that selective venous sampling correctly identified the presence of a tumour in all 19 patients, and correctly excluded the diagnosis in 11 of the 12 remaining patients--an overall success rate of 97%. Success rates of 88% for arteriography and 84% for computed tomography were recorded, though these investigations were not performed in all patients. Ultrasound and intravenous urography were much less accurate. On the basis of this study a sequence of investigation is proposed for patients with a suspected phaeochromocytoma. Computed tomography occupies a central role in this sequence with venous sampling (and occasionally other techniques) being used only as complementary investigations when specific indications for their use exist.  相似文献   

6.
A management plan for patients with suspected focal liver lesions which avoids early biopsy includes routine laboratory investigations, ultrasound scanning, and assessment for evidence of extrahepatic metastases and non-hepatic primary tumours. Angiography and computed tomography may also be indicated, and laparotomy or laparoscopy is undertaken to assess any potentially resectable focal liver lesions. The plan requires modification to suit individual circumstances.  相似文献   

7.
Renal masses found by intravenous urography, ultra-sound scanning, and arteriography were needled in 102 patients. Simple renal cysts containing clear fluid and no cytological abnormalities were found in 85 patients. Two unsuspected renal cell carcinomas were found on puncture; cytological examination showed malignant cells in the aspirate. Another five renal tumours were needled deliberately before nephrectomy, and a firm preoperative diagnosis of renal cell carcinoma was made on aspiration cytology in three. Benign cysts which had bled were particularly hard to diagnose. With care, radiology and cytology in combination can provide the firm diagnostic base needed for sound clinical management. The radiology-cytology team must be alert to the unusual finding that indicates a complex lesion, such as an unsuspected renal tumour.  相似文献   

8.
The diagnosis of the anatomic and functional state of urinary organs in girls with internal genital malformations and space-occupying lesions involves magnetic resonance imaging by administering the optimized dose of a magnetic resonance contrast agent (MRCA). The technology makes it possible to evaluate the anatomic features of the urinary tract (magnetic resonance urography), to perform abdominal vascular magnetic resonance angiography, and to draw a conclusion on renal functional status in the use of dynamic magnetic resonance renography. Within a study using one injected MRCA dose, both the anatomic and functional state of the kidney status can be examined, by evaluating MRCA passage singly in the cortical and medullary substances and pelvises, which increases diagnostic accuracy by 46% and promotes the optimization of management tactics in this category of patients.  相似文献   

9.
Henoch-Sch?nlein purpura (HSP) is the most common childhood systemic small-vessel vasculitis with skin, joint, gastrointestinal (GI) and renal involvement. Uncommon GI complications are intussusception, bowel perforation and rarely reported appendicitis. HSP-associated stenosing ureteritis represents a rare and potentially serious complication. We present a 5-year-old boy with severe and prolonged course of HSP and three very rare complications that occurred sequentially: appendicitis, intussusception and ureteritis. Only three days after admission, he developed clinical signs of acute appendicitis indicating surgical intervention. Histological analysis of excised appendix showed inflammation but without signs typical for vasculitis. Two weeks later, with the reccurence of HSP he again developed clinical picture of acute abdomen. Ultrasound and radiologic evaluation demonstrated ileo-ileal intussusception and the second laparotomy was undertaken. Histological analysis of the resected bowel tissue showed typical signs of leucocytoclastic vasculitis. In the fourth week of his illness, serial urinalysis showed nephritic urinary sediment indicative of renal involvement. Unexpectedly, control abdominal ultrasound demonstrated mild hydronephrosis of the left kidney, not seen on previous ultrasound evaluations. Undertaken excretory urography and computed tomography (CT) scan showed stenosis of upper/ midureter with mild dilation of upper part of the left ureter suggesting unilateral HSP-associated stenosing ureteritis. Eventually, the patient was discharged and closely followed-up for the next two years. He had no further reccurence of HSP, the urinalysis normalized after six months, while mild unilateral hydronephrosis remained unchanged. Our search of the literature did not show reports of HSP complicated by appendicitis, intussusception and ureteritis, and to our knowledge this is the first case with three different illness events that occured sequentially. We emphasize the necessity of repeated ultrasound evaluations in the course of HSR especially in cases with severe GI and renal invovement.  相似文献   

10.
The diagnostic capacities of three imaging methods: B-mode ultrasonography, computed tomography (CT), and magnetic resonance imaging (MRI) in orbital hemangiomas in babies were compared. Orbital ultrasound, computed tomography, and MRI scans were examined in 358, 384, and 48 babies, respectively. Their mean age was 6.7 months. Out of three techniques, ultrasound scanning proved to be of less informative value. MRI and CT were much more informative although each of them had advantages and limitations. The authors give some preference to CT despite its ionization.  相似文献   

11.
We present a case of a 68-year-old woman with a history of mild smoking and chronic bronchitis who showed recurrent hemoptysis. She presented with a nearly normal chest roentgenogram, a non-diagnostic fiberoptic bronchoscopy and a computed tomography and lung scanning both of which were highly suggestive for malignancy. In fact, the former showed obstruction of the main left bronchus, of the superior bronchus for the left upper lobe and of the apical bronchus for the left lower lobe, the latter showed a total cessation of blood flow through the left lung. Pulmonary angiography, however, was normal and aortography showed dilatated and twisted left bronchial arteries. Computed tomography and lung scanning came back to normal after bronchoscopic aspiration of endobronchial clots and a nonspecific antibiotic therapy were carried out. Although very infrequent, bronchial stenosis on CT and complete monolateral unperfusion on lung scintigraphy may occur in patients with hemoptysis of benign origin. We recommend the use of pulmonary arteriography in patients with the above pattern when diagnostic doubt remains after bronchoscopy.  相似文献   

12.
Senior neuroradiologists or radiologists of 42 hospitals with computed tomography available for NHS patients in England and Wales were contacted by postal questionnaire about the use of this facility in the management of patients with acute head injuries. Replies were obtained from 39 hospitals. Requests for computed tomography from general surgeons or physicians and staff of accident and emergency departments received positive responses for scanning with only half to three-quarters the frequency of responses to requests from neurosurgeons. Continuous computed tomography facilities were available generally to neurosurgeons. The combined effect of partial responses to requests and the availability of the computed tomography service meant that only 44% of hospitals gave a continuous service for general surgeons or physicians. The percentage of hospitals giving a continuous service to accident and emergency departments was 54%. It appeared that computed tomography scanning was being used most often as a diagnostic/management instrument after clinical selection among patients with head injuries rather than as an instrument to be used in primary assessment.  相似文献   

13.
OBJECTIVE: To evaluate the diagnostic value of the noninvasive method of image-guided needle aspiration cytology (NAC) in the assessment of radiologically detected pelvic and retroperitoneal space-occupying lesions (excluding the pancreas, kidney and adrenal). STUDY DESIGN: NAC was performed under computed tomographic or ultrasound guidance on 112 patients suspected of having a pelvic or retroperitoneal mass. Cytologic examination was performed on site after staining smears with the Papanicolaou method. In addition, air-dried smears, fixed smears, filter preparations from needle washings and cell blocks were studied. The NAC diagnosis was supported by examining cell blocks; further support was obtained with a tissue biopsy in some cases. Additionally, pertinent immunoperoxidase and/or histochemical studies were done. RESULTS: Eighteen cases were diagnosed as inflammatory lesions, 17 cases consisted of normal cellular elements, and 12 cases showed scanty material and were considered unsatisfactory/inadequate for a diagnosis. Five cases were suspicious for malignancy, and in 39 cases metastatic tumors were diagnosed from a previously known primary. Thirteen cases were diagnosed as lymphoma, and in 8 cases a diagnosis of soft tissue sarcoma was made. There were no false positive diagnoses of malignancy. Cell block preparations and immunohistochemistry were helpful with tumor typing, although lymphoma subtyping and soft tissue tumor typing generally required open biopsy. CONCLUSION: NAC, as the first-line investigation, is not only useful in the diagnosis of space-occupying lesions of the pelvic and retroperitoneal region but can also help in choosing appropriate management. The technique is most useful in diagnosing metastases but is also helpful in excluding malignancy in some cases and in suggesting diagnoses of lymphomas and soft tissue tumors.  相似文献   

14.
Systemic candidiasis with Candida-induced abscesses, predominantly in the liver and the spleen, was diagnosed in 27 patients with haematologic malignancies after intensive cytostatic therapy. Specific features included septic fever unresponsive to antimicrobial therapy, hepatosplenomegaly with multiple lesions in the liver and spleen (diameter up to 2 cm) as detected by computed tomography (CT) or ultrasound, and an elevation in liver enzymes. During treatment, induced neutropenia, hepatic and splenic foci were poorly defined histologically and were not identified by imaging procedures. After granulocyte recovery these foci showed characteristic histological patterns. Ultrasound and/or CT investigations of the abdomen now revealed characteristic lesions in the liver and the spleen. Gamma-GT and alkaline phosphatase were early indicators of hepatic involvement in Candida septicaemia and were often already elevated in aplasia.  相似文献   

15.
Renovascular hypertension can result from renal artery lesions involving the main renal artery, or its branches. It is generally felt that the elevation of blood pressure results from excessive systemic vasoconstriction secondary to enhanced renin secretion by one or part of one kidney. Renin secretion is enhanced because of constriction of the renal artery and resultant intrarenal ischemia. Clinically patients cannot be distinguished from those with essential hypertension and diagnosis must be made with arteriography although urography and isotope renography may suggest the diagnosis. Surgical cure can be predicted if differential renal vein renin ratios lateralize but a non-lateralizing study does not necessarily mean that surgery will fail. In properly selected patients, surgical results are excellent.  相似文献   

16.
Among the first 111 patients with renal masses examined by ultrasound most renal cysts (98%) and carcinomas (86%) were correctly detected. Diagnostic accuracy was high when ultrasound predicted a renal cyst (97%), but renal carcinoma accounted for only 60% of the complex echo masses found. Ultrasound was used as the primary, non-invasive test for the selection of outpatients with simple renal cysts for diagnostic puncture and for the selection of those with complex renal masses for more elaborate and expensive inpatient investigation. Ultrasound is not infallible but a safe diagnostic pathway may be drawn up in which ultrasound errors are not allowed to lead to diagnostic disasters. This approach reduced the use of arteriography for renal masses by two-thirds. With care the diagnosis of the common chance finding of a renal mass can be made simpler, safer, and cheaper.  相似文献   

17.
Michael Brown  John D. Battle  Jr. 《CMAJ》1964,91(15):786-790
Reports in the medical literature of seven patients with multiple myeloma who died of acute renal failure following intravenous urography prompted a study of 39 patients with multiple myeloma who were subjected to intravenous urography at the Cleveland Clinic from 1940 to 1959. Four developed acute renal failure and two died within three weeks. All four revealed evidence of renal damage, or insufficiency, or both prior to urography. Thirty-five patients, 15 of whom had renal damage, had no untoward reaction to intravenous urography. These observations suggest that urography is associated with a small but definite risk in patients who have multiple myeloma and renal involvement.  相似文献   

18.
OBJECTIVES--To assess whether ultrasonography alone is adequate for routine screening of childhood urinary infection, whether clinical features determine the need for further investigations, and which investigations are most appropriate. DESIGN--Prospective survey of children with proved urinary infection and a preinvestigation record of clinical features. Ultrasonography and intravenous urography were routine, with choice of further studies determined by ultrasonographic findings. SETTING--A children''s hospital and two district general hospitals in Mersey region. MAIN OUTCOME MEASURES--Sensitivity and specificity of ultrasonography both generally and in relation to clinical features. Accuracy of intravenous urography compared with radioisotope examinations. RESULTS--Specificity of ultrasonography was good (99% (95% confidence interval 96% to 100%)) but sensitivity modest (43% (32% to 55%)), principally with respect to detecting vesicoureteric reflux and renal scarring. Among older children (aged 2-10 years) with positive ultrasound results and fever or vomiting the sensitivity in detecting reflux (with and without renal scarring) was 78% (62% to 89%) and the specificity 69% (60% to 78%); in detecting renal scarring (with and without reflux) the sensitivity was 100% (80% to 100%) and specificity 65% (56% to 74%). Renal scarring and obstructive uropathies were better assessed by radioisotope examinations than by intravenous urography. CONCLUSIONS--Ultrasonography alone is inadequate for routine screening of childhood urinary infection. Though further investigations remain advisable in infants, in older children they can be restricted to a minority who have positive ultrasound examinations or have had fever or vomiting. Radioisotope examinations largely eliminate the need for intravenous urography.  相似文献   

19.
The underlying principles of nuclear medicine imaging involve the use of unsealed sources of radioactivity in the form of radiopharmaceuticals. The ionizing radiations that accompany the decay of the administered radioactivity can be quantitatively detected, measured, and imaged in vivo with instruments such as gamma cameras. This paper reviews the design and operating principles, as well as the capabilities and limitations, of instruments used clinically and preclinically for in vivo radionuclide imaging. These include gamma cameras, single-photon emission computed tomography (SPECT) scanners, and positron emission tomography (PET) scanners. The technical basis of autoradiography is reviewed as well.  相似文献   

20.
The study was undertaken to enhance the diagnostic capacities of excretory urography in evaluating renal function, by determining the renal clearance of a contrast medium. The main task of the study was to develop bloodless and rather reliable ways of estimating the volume of the body's distributed contrast medium and its urinary concentration in the patient at urography. Excretory urography was performed in 248 patients aged 12 to 75 years. The specific gravity of excreted urine was determined with a standard laboratory urometer to 0.001 g/cm3. Absoption spectrophotometry was used to determine the serum concentration of contrast medium in 67 patients. The values of concentrations were plotted in the semilogarithmic ordinate system, followed by extrapolation of the initial segment of the plot to the so-called zero point determining the value of the concentration of contrast medium at the moment of its complete distribution in the intercellular space. The derived value was compared with the medium's dose coming into the body, which made it possible to determine the degree of dilution of the substance, i.e. the volume of its distribution in the organism. There was a linear relationship between the concentrations of renally eliminated contrast medium and the specific gravity of excreted urine. The numerical value of the constant reflecting this relationship is equal to 6. There was evidence for that such studies could be made by routine urometry. A high correlation was found between the body mass and the volume of distribution of contrast medium in the intercellular space. The discovery of the above regularities permitted the procedure for measuring the values of two most important physiological renal process (glomerular filtration and trabecular water reabsorption) to be simplified and widely available. The paper outlines the great promises for using excretory urography as a scanning functional test during a primary study and a follow-up of the patient's status.  相似文献   

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