Biomedical subjects
Publications and source records attributed to B N Raghavendra.
CT scans of 12 patients with renal infarcts were reviewed. CT findings along with the clinical presentation were diagnostic in 10 cases. Correlation with angiography (5 cases) and sonography (8 cases) was made. The diagnosis of renal infarction can usually be made on the basis of specific CT findings. Angiography is valuable in helping to establish the cause and direct treatment.
Six cases of inflammatory aneurysm of the abdominal aorta are described. All patients were male, aged 59 to 80 years, and five had symptomatic atherosclerotic cerebrovascular or cardiovascular disease. In three the diagnosis of inflammatory aneurysm was suggested preoperatively on the basis of computed tomographic or ultrasonographic scanning. On gross examination the aneurysm wall was about 1 cm thick and included an inner narrow layer of atherosclerotic plaque, which was contiguous with the outer thick fibroinflammatory component. Microscopically, this component consisted of fibroblasts and collagen, which entrapped fat, nerves, and lymph nodes and was infiltrated by lymphocytes and plasma cells. Plasma cells, lymphocytes, and fibroblasts predominated in four patients, while two showed abundant dense collagen with fewer inflammatory cells and fibroblasts. There was associated vasculitis, predominantly phlebitis, in three. Inflammatory aneurysms represent a distinct group of abdominal aortic aneurysms.
During a two-year period, intra-operative ultrasonic explorations were performed in 44 patients for the purpose of localisation of intracranial masses. This facilitated accurate intraoperative assessment of the location and consistency of the mass. We consider operative ultrasound to be an invaluable adjunct to surgery of small intracerebral masses.
Ultrasound was correlated with angiography for assessment of tumor extension to the intrahepatic inferior vena cava, hepatic veins, and portal vein branches in 15 cases of hepatocellular carcinoma (HCC) and 85 cases of hepatic metastases. Sonography revealed intraluminal tumor thrombus in 5 cases of HCC (33%), which were confirmed by angiography (sensitivity and specificity = 100%), and in 1 case of hepatic metastases (1%). Sonography was superior in depicting veins obscured or nonopacified on angiography, which in turn demonstrated arteriovenous shunting not appreciated on sonography. Used as the initial procedure for evaluation of venous extension of HCC, ultrasound can suggest the histology (though this must be confirmed by biopsy) and determine the feasibility of resection.
High-resolution real-time ultrasonography was performed in 11 patients with clinically suspected deep venous thrombosis (DVT) of the lower extremity. Contrast venography was performed in all patients within 24 hours of sonographic examination. The common femoral vein at the groin and the popliteal vein in the popliteal fossa were evaluated for presence or absence of intraluminal soft-tissue mass (thrombi), compressibility of the veins, and response to performance of the Valsalva maneuver. Of the 11 patients, six were shown to have DVT by contrast venography. In all six cases there was complete agreement between sonography and contrast venography as to the presence or absence of thrombi in the common femoral vein or the popliteal vein.
With the routine use of sonography in the evaluation of patients with pelvic masses, it is essential to be familiar with the sonographic features of fallopian tube carcinoma so that diagnosis can be made early and thus contribute to prompt management of these patients. The authors present the clinical manifestations, sonographic features, and pathologic correlations in three cases of fallopian tube carcinoma.
Sonographic features in 12 cases of proven cholangiocarcinoma were analyzed and correlated with findings on direct cholangiography. Proximal bile duct dilation was present in all cases of cholangiocarcinoma of the intrahepatic ducts except one. A neoplastic bile duct segment was detected in nine of the 12 cases. The neoplasms were seen as narrowed, normal-sized, or enlarged ducts, and contained intraluminal soft-tissue echoes or echogenic bands across the lumens. The sonographic accuracy was greater for lesions involving the bifurcation and the common hepatic duct than for common bile duct lesions. Cholangiography was superior to sonography in determining the length of the involved segment, whereas sonography was superior in detecting hepatic invasion and lymphadenopathy.
In a series of 225 patients with lymphoma studied by computed tomography, involvement of the kidney(s) was found in 11 (4.9%). These cases were then also studied by ultrasound. Because of the characteristic findings of computed tomography and sonography in renal lymphoma, a reliable diagnosis was possible along with an accurate assessment of the incidence and types of renal involvement. Illustration of this material along with a discussion of the clinical implications of these findings is presented.
Portosystemic venous collaterals were studied with sonography in 40 patients with known portal hypertension. Eight patients had technically inadequate scans, while 32 had optimal scans. Sixty groups of venous collaterals were identified. At least one collateral pathway was seen in 28 patients, for a sensitivity of 88% for the 32 patients with optimal scans and 70% for the total group. The overall sensitivity for detection of coronary-gastroesophageal collaterals was 80% and 64%, respectively. The small size of the coronary-gastroesophageal varices in early portal hypertension seems to be the most important factor limiting detection in patients suitable for sonography.
A retrospective review of 96 abdominal abscesses yielded 11 cases (9%) that were diffusely echogenic on sonograms and that stimulated findings of solid lesions. Sonographic features of these abscesses were analyzed and compared with features of 78 cases of hepatic metastasis. An abscess was considered solid appearing when it contained diffuse internal echoes that were distributed over 90% of the abscess cavity. The visualized internal echoes were of low to medium amplitude, and were generally similar to the normal echogenicity of the parenchymal organs, such as the liver, spleen, or uterus. Distal acoustic enhancement was seen in 91% of the solid abscesses, and it was not seen in hepatic metastases. A distinct echogenic wall was present in 64% of the abscesses (subacute and chronic lesions), but this occurred in less than 4% of metastases. Thin peripheral halos inside or outside of and adjacent to the abscess wall were seen in 36% of abscesses. The peripheral halos seen in metastases were wider and not associated with an echogenic wall. The diagnosis of a diffusely echogenic abscess and differentiation from a neoplasm is possible when the sonographic findings of acoustic enhancement, thin peripheral halo, and echogenic abscess wall are present.
Sonograms of six patients with adenomyomatosis of the gallbladder were reviewed and correlated with oral cholecystographic and pathologic findings. The gallbladder was visualized in four of the six patients by oral cholecystography, which also revealed intramural diverticula. Five of the six patients showed sonographic evidence of diffuse or segmental thickening of the gallbladder wall and intramural diverticula, seen as anechoic or echogenic foci within the wall. Intramural diverticula containing bile appeared as anechoic spaces; those containing biliary sludge or gallstones appeared as echogenic foci with or without acoustic shadows or reverberation artifacts. There was good correlation between sonographic and pathologic findings in three patients. The authors conclude that adenomyomatosis of the gallbladder should be suspected when (a) there is diffuse or segmental thickening of the gallbladder wall and (b) intramural diverticula are seen as anechoic or echogenic foci with or without associated acoustic shadows or reverberation artifacts.
The clinical and radiologic findings of tuberous sclerosis in three family members, which manifested as renal insufficiency due to extensive renal cystic disease, are described. The family was thought to have polycystic kidney disease until coexisting tiny angiomyolipomas were found among the cysts (by computed tomography in two patients and at autopsy in one). The radiologic and pathologic factors that establish the diagnosis of renal cystic disease associated with the tuberous sclerosis complex are reviewed.
The myelographic evaluation of patients presenting with persistent or recurrent symptoms following surgery for an intrinsic spinal cord mass is difficult. Possible symptom-causing processes include tumor recurrence, intramedullary cyst formation, postirradiation effects, arachnoiditis, and spinal cord atrophy. Since tumor recurrence and syrinx formation may require further surgery, while the other entities generally do not, the distinction between these processes is clinically important. The authors have successfully employed commercially available high-resolution real-time ultrasound imaging systems to investigate a group of patients with these persistent or recurrent symptoms after surgery. The bony laminectomy defect provides an acoustic window for viewing intraspinal contents. Ultrasound can accurately differentiate between cystic and solid lesions and can clearly demonstrate whether a spinal cord is enlarged or atrophic.
High-resolution real-time ultrasonography of the lumbosacral spine was performed in 10 control patients and in six patients with suspected spinal dysraphism. The spinal cord was readily visualized in both groups. Lack of ossification of the posterior arch of the spine in normal infants and the presence of a bony defect in patients with spina bifida permit sonographic investigation of the spinal canal and its contents. It is concluded that the diagnosis of spinal cord tethering can be established rapidly by high-resolution real-time ultrasonography, which may be used in screening patients with suspected occult spinal dysraphism.
Sonograms of 73 patients with 92 hydronephrotic kidneys were prospectively reviewed in an attempt to differentiate hydronephrosis from pyonephrosis. Sonographic diagnosis of pyonephrosis was based on the presence of persistent internal echoes, dispersed or dependent, within the dilated pelvocaliceal system. In group 1, consisting of 38 patients without clinical evidence of renal infection, sonography revealed the collecting system distended by urine to be anechoic, for a specificity of 100%. In group 2, consisting of 34 patients with clinical suspicion of renal infection, sonography showed internal echoes within the fluid-filled collecting system in 10 cases; nine of these had pyonephrosis (sensitivity of 90%), and one had hemorrhagic debris without infection (false-positive rate 3%). In the other 24 patients, sonography correctly predicted the absence of infection in all but one case (specificity 97%, false-negative rate 10%). It is concluded that in patients with clinical suspicion of renal infection, sonography has a high degree of accuracy (96%) in the differentiation of pyonephrosis from hydronephrosis.
Review of sonograms in 84 patients with documented tubal pregnancies yielded 15 cases with discrete, diffusely echogenic, adnexal masses (18%). All these cases were proven at surgery to represent hematosalpinx containing clotted blood. The characteristic sonographic findings in these cases enabled an accurate preoperative diagnosis in 12 consecutive patients. Hematosalpinx containing clotted blood was seen as a diffusely echogenic adnexal mass accompanied in most cases by areas of high-intensity echoes. Pelvic hemoperitoneum (five cases) was diffusely echogenic due to clotted blood, and its recognition enabled evaluation of the upper abdomen for extension of hemorrhage. The echogenicity of the adnexal mass and pelvic hematoma was similar to that of the uterus, resulting in obscuration of its contour. The following sonographic features are characteristic of tubal pregnancy in the proper clinical setting: (1) absence of intrauterine gestation; (2) diffusely echogenic adnexal mass with areas of high-intensity echoes; and (3) diffusely echogenic hematoma in the pouch of Douglas.
Small fat-containing intraparenchymal renal lesions, 0.5 to 1.3 cm in diameter, were detected by sonography and computed tomography in six patients. In five of the six cases, the lesions were found serendipitously. None of the patients underwent surgery. Follow-up studies, performed over a period of 6-24 months, showed no change in the size of the lesions. These small fat-containing nodules, hitherto unrecognized by imaging studies, are not an uncommon finding at routine autopsy. Since these lesions do not show growth in the adult population, surgical intervention does not seem to be indicated.
Fifty-six patients with clinical threatened abortion were evaluated by sonography. In six patients, fetal cardiac activity was absent at or beyond 9 weeks of gestation, and fetal death was confirmed in all six cases. In the other 50 patients, fetal cardiac activity was present at or beyond 9 weeks of gestation. In 10 (20%) of these 50 patients, subchorionic bleeding was present in various degrees, appearing sonographically as an extrachorionic crescentic anechoic or complex collection. The final outcome in the 50 patients with fetal cardiac activity was as follows: In the absence of subchorionic bleeding, 100% of the pregnancies progressed to term; in the presence of subchorionic bleeding the positive outcome was reduced to 80%. In addition to signs of fetal life on sonography, subchorionic bleeding is an important factor affecting the outcome of gestations in patients with clinical threatened abortion.