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V Raptopoulos

Publications and source records attributed to V Raptopoulos.

At least 91 records · Page 5Linked to original sources

Renal fascial pathway: posterior extension of pancreatic effusions within the anterior pararenal space.

Retrorenal extension of pancreatic effusion or phlegmon associated with pancreatitis has been described frequently and is generally considered to represent extension of these processes from the anterior into the posterior pararenal space. A series of meticulous cadaveric dissections (n = 8) and a review of a large number of patients with pancreatitis (n = 53) show that these posterior collections actually represent extension of pancreatitis from the anterior pararenal space to a potential space between the laminae of the posterior renal fascia. Of 40 patients with posterior extension of pancreatic effusion or phlegmon, interfascial involvement was observed in all 40 and was bilateral in nine (23%). True involvement of the posterior pararenal space was uncommon, as was extension into the perirenal space. This phenomenon appears as a continuum of the well-described thickening of the renal fascia secondary to pancreatitis. It can be explained by new observations of the relationships between the fascia of Gerota and the lateroconal fascia.

Cadaver↗

Imaging of questionable and unusual pelvic masses.

Ultrasonography is usually the initial diagnostic examination performed for evaluating gynaecological conditions and pelvic masses. The authors' experience with 11 "problem cases" and a review of the literature of such enigmas has led to the following recommendations in the following order: a plain radiograph or repeat ultrasound study; ultrasound study with the water enema technique; gastrointestinal examination if the answer is still not apparent, followed by computed tomography or a real-time ultrasound study during a clinical pelvic examination.

Adnexal Diseases↗

Chronic acalculous gallbladder disease: multiimaging evaluation with clinical-pathologic correlation.

Despite the recent advances in hepatobiliary imaging, the diagnosis of chronic acalculous gallbladder disease remains difficult. A retrospective study was undertaken to assess the value of a multiimaging approach in detecting chronic acalculous gallbladder disease and in predicting which patients would obtain symptomatic relief after cholecystectomy. Of 199 patients with chronic cholecystitis, 26 (13%) had no gallstones. Of these 26, only 17 (65%) had symptoms related to chronic cholecystitis; in the remainder, the histologic diagnosis was made incidentally. After cholecystectomy, 13 (76%) of the 17 symptomatic patients obtained long-term symptomatic relief, while in four, the symptoms recurred. Among patients with histologic changes of chronic cholecystitis, biliary scintigraphy was the most sensitive technique (sensitivity, 89%). The sensitivity of sonography and oral cholecystography was 61.5% and 66%, respectively. However, for identifying symptomatic patients who may obtain long-term symptomatic relief after cholecystectomy, the accuracy of sonography, oral cholecystography, and biliary scintigraphy was 82%, 86%, and 38%, respectively. When two tests were in agreement the accuracy was 88%. For chronic acalculous cholecystitis, more than one study must be performed in order to make the correct diagnosis and to predict good results from cholecystectomy.

Adult↗

Bile-duct dilatation after laparotomy: a potential effect of intestinal hypomotility.

Dilatation of unobstructed extrahepatic bile ducts was observed in patients with conditions associated with intestinal hypomotility. For further investigation of this association, a prospective study was undertaken in which the common hepatic duct was measured in 15 patients before and 1 day after laparotomy, when all patients had postoperative paralytic ileus. A statistically significant (p less than 0.01) increase in the mean diameter of the hepatic duct was observed postoperatively. When compared with the preoperative measurement, the mean diameter of the duct almost doubled, from 3.3 to 5.9 mm. This phenomenon may be due to persistent contraction of the sphincter of Oddi that occurs when intestinal hypomotility eliminates the stimuli for cholecystokinin release.

Adult↗

Computed tomography of the superior vena cava.

The superior vena cava (SVC) can be visualized and reliably evaluated by computed tomography (CT). Opacification of this vessel with iodinated contrast material and multiplanar reformations can provide information concerning the patency of the lumen and the relationship of the SVC with adjacent mediastinal and lung structures, both normal and abnormal. SVC obstruction leading to SVC syndrome is the most common condition affecting this vessel. It can be caused by both extrinsic compression and intraluminal thrombosis. Numerous collateral pathways have been described by conventional radiographic and anatomic studies with the azygos vein being the most important collateral vessel. From this aspect, five distinct grades of SVC obstruction can be identified. Grade 0: SVC narrowing without clinical evidence of SVC syndrome. Grade I: Moderate SVC narrowing without collaterals. Grade II: Severe SVC narrowing with the azygos vein serving as partial collateral. Grade III: SVC obstruction above the azygos arch. Grade IV: SVC obstruction at or below the level of the azygos arch. Patients with Grades I to IV have clinical evidence of SVC syndrome, and the CT grading roughly corresponds to the severity of clinical findings. CT accurately depicts both the site of SVC obstruction and important collateral pathways and clearly distinguishes between SVC thrombosis and external compression. In this regard, it provides unique information not available from other modalities such as conventional or radioisotope venography. Furthermore, in a number of patients with suspected SVC obstruction, this vessel may be patented, leading to clinical reassessment. The only disadvantage of CT as compared with radionuclide flow studies is the potential hazard from i.v. administration of iodinated contrast material. Less common abnormalities of the SVC include congenital or developmental conditions, such as persistent left SVC, aneurysms, dilation of the vessel due to heart failure, and variations (usually tortuosity) of the thoracic inlet vessels. We conclude that CT should be used as the procedure of choice for the diagnosis of SVC abnormalities, especially in patients with suspected SVC syndrome.

Abscess↗

The anterior diaphragmatic attachments: an anatomic and radiologic study with clinical correlates.

A study of the anterior attachments of the respiratory diaphragm was performed using gross anatomic specimens, plain radiography, and computed tomography with multiplanar image reformatting. The anterior portions of the diaphragm are affixed to the lower six ribs and the sternum. The line of attachment of each hemidiaphragm begins at the anterior axillary line and extends cranially and medially to meet at the xiphoid process. These structures can be visualized along with contiguous pathologic subdiaphragmatic and/or infradiaphragmatic air collections. In the semierect patient, free intraabdominal air may preferentially collect in the anterior subdiaphragmatic regions rather than below the domes of the diaphragm, providing a subtle but reliable indication of pneumoperitoneum. An understanding of the normal anatomy of the anterior diaphragmatic attachments is valuable in assessing a variety of anterior paradiaphragmatic air collections.

Air↗

Peritoneal mesothelioma.

The definitive diagnosis of peritoneal mesothelioma and its differentiation from metastatic peritoneal carcinomatosis may be difficult because of the clinical, macroscopic, and microscopic variability of the tumor. To this purpose, a combination of criteria, including the clinical picture, the gross pathologic findings, the exclusion of other primary neoplasms, and the microscopic findings, must be taken into consideration. Conventionally, these criteria may be established only after surgical exploration and extensive sampling. Our experience with patients with peritoneal mesothelioma and metastatic peritoneal carcinomatosis, as well as a review of the recent imaging literature, shows excellent correlation between computed tomography or ultrasound and the operative or autopsy findings. These imaging modalities showed soft-tissue masses or nodules; thickened omentum ("omental cake"), peritoneum, mesentery, and bowel wall; pleural plaques; and usually disproportionally small, if any, ascites. The latter two observations may be useful in differentiating mesothelioma from carcinomatosis macroscopically. Furthermore, fine-needle aspiration biopsy, after performing wide sampling of the tumors in different locations under ultrasonic or computed tomographic guidance, produced diagnostic cytologic specimens. Thus, the need for exploratory surgery may be alleviated, and the diagnosis of peritoneal mesothelioma may be made prospectively and relatively noninvasively with the use of computed tomography or ultrasound and fine-needle aspiration biopsy. Since epidemiologic studies predict increasing incidence of this neoplasm, especially among asbestos workers, it is suggested that these techniques be seriously considered as screening methods for high-risk populations.

Adult↗

The subarachnoid spaces in children: normal variations in size.

Intra- and extraventricular subarachnoid spaces in children were studied by high-resolution computed tomography. Scans were reviewed of 34 patients who were selected as highly likely to have normal scans. Sizes of the ventricular system and the seven extraventricular subarachnoid compartments were analyzed and graded on a subjective scale from 0 (not visible) to 4 (markedly enlarged). Data were also analyzed by age group (greater or less than 2 years of age). The subarachnoid spaces were found to be both larger and more variable in size before the age of 2 years and to be quite uniform thereafter. Based on these findings, it is inadvisable to base specific diagnoses during the first 2 years of life solely upon modest enlargement of the subarachnoid spaces.

Age Factors↗

Diagnosis of peritoneal mesothelioma: computed tomography, sonography, and fine-needle aspiration biopsy.

The diagnosis of peritoneal mesothelioma was made prospectively and noninvasively in four patients with the use of sonography, computed tomography, and sonographically guided fine-needle aspiration biopsy. The imaging methods revealed information similar to the operative findings, with clear superiority of computed tomography over sonography. These noninvasive methods may be used as screening tools, especially among groups or in regional areas with a high risk for asbestos exposure. The findings included soft-tissue masses with invariable involvement of the omentum; small intraperitoneal nodules; thickened peritoneum, mesentery, and bowel wall; pleural plaques; and usually minimal, if any, ascites. Since the differential diagnosis from peritoneal carcinomatosis may be difficult, sonographically (or CT) guided aspiration biopsy is needed to produce diagnostic cytologic specimens. The use of this type of biopsy should obviate surgical exploration.

Aged↗

Dynamic cholecystosonography of the contracted gallbladder: the double-arc-shadow sign.

In 41 of 55 patients in whom the gallbladder lumen was not identified by static sonography, a specific image was observed with dynamic scanning. This consisted of two parallel arcuate echogenic lines separated by a thin anechoic space with distal acoustic shadowing: the "double-arc-shadow" sign. The proximal arc represents the near wall of the gallbladder, the anechoic space is bile in the gallbladder lumen, and the distal arc represents the gallstone(s) responsible for the acoustic shadowing. Of the two additional sonographic patterns observed, the "'echo-shadow" pattern, which was seen with static scanning in 44 and with dynamic scanning in eight patients was an accurate, indirect indicator for cholelithiasis. On the other hand, "nonvisualization" was an unreliable sign. Of 11 such patients scanned with static and six with dynamic scanning, four proved to have a normal gallbladder. Comparing static with dynamic cholecystosonography in patients with nonphysiologically contracted gallbladders, the accuracy rate for cholelithiasis increased from 86.3% (44 of 51 patients) to 96% (49 of 51). In 41 of these patients (80%) the double-arc-shadow pattern positively identified the gallbladder lumen, increasing the confidence of the examiner. Furthermore, these images can be produced in a fraction of the time required for complete evaluation with static scanning.

Cholelithiasis↗

Acute osteomyelitis: advantage of white cell scans in early detection.

Acute osteomyelitis was induced in 18 rabbits after direct injection of a solution of Staphylococcus aureus culture into a proximal tibial metaphysis. Serial plain radiographs and radionuclide studies with indium-111 oxide labeled while blood cells and technetium-99m methylene diphosphonate were performed over the next 4 weeks. Visual and quantitative analysis by measuring the isotope activity of 111In and 99mTc over the infected tibias as compared with the opposite bones revealed that the white blood cell scans were positive in 15 (83%) of the 18 rabbits during the first week after injection of the microorganism. During the same period, the 99mTc bone scans were positive in only 22% of the animals (p less than 0.005). In the animals that survived, both white blood cell and bone scans were positive during the second week, and thereafter, the bone scans revealed consistently higher activity than was observed with white blood cell scans. Computed tomography performed in six rabbits revealed an increased attenuation coefficient of the medullary cavities in the infected bones of four animals during the first week and of one more during the second week. Plain radiographs became positive after the 12th day. Results indicate that in patients with suspected acute osteomyelitis, white blood cell scans and probably computed tomography can detect the disease earlier than 99mTc bone scans and plain radiographs.

Animals↗

Comparison of real-time and gray-scale static ultrasonic cholecystography.

The authors compared the diagnostic accuracy of gray-scale static scanning and high-resolution real-time ultrasonography in the evaluation of gallbladder disease in 339 patients. With real-time scanning, the gallbladder was seen in 97.6% of cases and gallstones were unequivocally demonstrated in 94.5% of patients with cholelithiasis, compared to 89.5% and 78.8%, respectively, with static scanning. Real-time scanning is more accurate because it can show the contracted, stone-filled gallbladder. It is also faster and more convenient to both patient and examiner, making it the procedure of choice in the primary evaluation of gallbladder disease.

Cholecystography↗

Imaging of the pancreas with computed tomography.

In this paper we present our experience with computerized tomographic imaging of the pancreas, both in normal and abnormal conditions. Eighty patients were studied for evaluation of pancreatic disease. A further 50 patients, all with a normal pancreas, were studied for abnormalities of other abdominal organs and served as the control group. Helpful signs in establishing the diagnosis of carcinoma of the pancreas were mass effect within the pancreas, alteration of organ contour and obliteration of retroperitoneal fat planes. We found that differentiation from pancreatitis or retroperitoneal lymphadenopathy may at times be difficult. Our results showed that in 22 out of 23 patients with proven normal pancreas, the pancreas size on the CT display was within the adopted normal range. In 30 patients with proven carcinoma of the pancreas, a pancreatic mass was seen in 24 (83%). Computerized tomography is clearly a valuable method for viewing both normal pancreatic anatomy and anatomical variations and pathologies.

Adipose Tissue↗

Computed tomography of solitary pulmonary nodules: experience with scanning times longer than breath-holding.

Thirty-one patients with solitary pulmonary nodules--18 benign and 13 malignant--proven by either tissue diagnosis or prolonged follow-up were evaluated by computed tomography (CT). A device (ACTA scanner 0100) with scanning times greater than breath-holding was used with full understanding of its related limitations. A retrospective study of the CT features of these nodules led us to establish several criteria for benign nodules. CT evidence of calcium is felt to be the most important feature of benignancy. In the absence of calcium, irregular nodule margins, perinodular fibrosis, satellite nodules, and pleural thickening opposite a peripherally situated nodule are helpful to suggest its benign nature.

Humans↗