Identification of clinical stage A nonseminomatous testis cancer patients at extremely low risk for metastatic disease: a combined approach using quantitive immunohistochemical, histopathologic, and radiologic assessment.

PURPOSE: To evaluate previously determined predictors of metastasis in low-stage testis cancer in a consecutive group of clinical stage A patients. PATIENTS AND METHODS: Ninety-one consecutive clinical stage A nonseminomatous germ cell tumor (NSGCT) patients who underwent primary nerve-sparing retroperitoneal lymph node dissection (NSRPLND) had orchiectomy specimens and computed tomographic (CT) scans evaluated blindly in a quantitative fashion. These scores were then correlated with pathologic stage using previously determined paradigms. RESULTS: Using volume of embryonal carcinoma in the orchiectomy specimen, lymph node diameters in the primary landing zones and MIB-1 staining of the orchiectomy specimen, 41 patients were classified as low risk for metastasis. Forty of these 41 had pathologic stage A disease at RPLND. CONCLUSION: These parameters can identify a low-risk group of patients for metastasis who can be rationally offered surveillance.

Prospective study of magnetic resonance imaging and SPECT bone scans in renal allograft recipients: evidence for a self-limited subclinical abnormality of the hip.

We recently reported that typical abnormalities of avascular necrosis (AVN) in magnetic resonance images (MRI) of the hips of asymptomatic renal transplant recipients whose plain radiographs are normal may improve spontaneously and even disappear completely. We present the results of serial bone scans, most of which were performed with single-photon emission computed tomography obtained over periods as long as 24 mo after transplantation in 72 of these patients. Three paired imaging studies (i.e., MR and bone scan performed within 30 days of each other) were available for each of these patients. In three patients, both the MR images and the bone scans showed changes consistent with bilateral AVN within 4 mo after transplantation. All three patients developed hip pain which was bilateral in two and unilateral in one. Two patients (three hips) required surgical intervention at which time AVN was found on pathologic examination of all three hips. None of the remaining 69 patients developed hip pain during the study. However, in nine patients whose MR studies were consistently normal, at least one bone scan was abnormal (13 hips). The presence of AVN was pathologically confirmed in each of the hips subjected to surgery. Where the imaging findings were identical to those in the asymptomatic patients as well as those in whom the imaging abnormality regressed, we suggest that the subclinical imaging abnormalities represent mild AVN, which is reversible in some cases. Since the process was identified in 10 hips by MRI and in 13 hips by bone scan, both studies are needed to detect subclinical AVN. This may be important if treatment of subclinical disease is clearly shown to prevent progression to symptomatic AVN.

Ioversol 320: a new nonionic, water-soluble contrast medium for body computed tomography clinical trial.

An open-label noncomparative clinical study was conducted to evaluate the safety, tolerance, and efficacy of ioversol (Optiray 320), a new low-osmolality nonionic contrast medium used in contrast-enhanced computed tomographic (CT) scanning. Forty-two adult patients who required contrast-enhanced body CT scanning participated in the study. Ioversol was administered to patients undergoing CT of the chest, abdomen, and pelvis. Most of the patients received a dose of 150 mL, with smaller doses administered if a patient weighed less than 50 kg or if a patient had only one functioning kidney. The quality of the CT scans was judged to be diagnostic in all 42 patients in the study, with the quality assessed as excellent in 35 patients and good in seven patients. Ioversol was considered well tolerated by patients in the study, with none reporting any pain from the contrast agent. Only mild or moderate sensations of heat were reported. There were no clinically significant changes in vital signs, and only one mild adverse reaction (determined to be procedure-related) was reported. Ioversol was found to be safe, well tolerated, and efficacious for use in body CT scanning.

Changes of hepatoma echo patterns with tumor growth. A study of the microanatomic basis in a rat model.

OBJECTIVES: The echo patterns of human hepatoma vary considerably as the tumors grow. This sonographic study investigates the microanatomic basis of the echo-pattern changes in an animal model. METHODS: ACI rats (n = 35) with intrahepatically implanted Morris hepatoma 3924A were imaged with 10-MHz ultrasound from days 7 to 28 after tumor implantation. The sonograms were precisely correlated with the histologic sections and microangiograms obtained from the same section plane. RESULTS: Small hepatomas (size = 6.6 +/- 1.6 mm) without necrosis demonstrated a low-echo pattern. Medium-sized tumors (size = 11.7 +/- 3.3 mm) had a low-echo periphery and a high-echo center. The low-echo periphery corresponded to viable tumor and the high-echo core corresponded to central coagulation necrosis. Large tumors (size = 20.9 +/- 7.5 mm) with extensive necrosis revealed an irregular mixed-echo pattern. CONCLUSIONS: The trend of increasing echogenicity of the hepatomas with tumor growth is due to the progression of coagulation necrosis.

Coronary calcium measurements by double helical computed tomography. Using the average instead of peak density algorithm improves reproducibility.

RATIONALE AND OBJECTIVES: Coronary calcium (CC) measured by fast computed tomography (CT) was proposed recently as a noninvasive method of monitoring the coronary atherosclerotic process. Assessment of the reproducibility of CC measurements (mainly interstudy variability) is essential for consistent interpretation of serial studies. METHODS: The authors scanned 74 patients (50 men and 24 women) twice on the same day to determine the interstudy variability of a new scoring algorithm, using the average instead of conventional peak CT density values. RESULTS: Nineteen patients had no calcium on either scan. In the remaining 55 patients, interstudy variability was decreased by 31% using the average algorithm (32%-23%; P < 0.001). CONCLUSIONS: Using the average instead of conventional peak density score provides better reproducible measurements of calcium by double helical CT.

Electrocautery of the tract after needle biopsy of the liver to reduce blood loss. Experience in the canine model.

RATIONALE AND OBJECTIVES: Bleeding is the most common complication of needle biopsy of the liver. This study was designed to assess the feasibility of using unipolar electrocautery to decrease bleeding. METHODS: Under general anesthesia, the livers of eight dogs were surgically exposed. A mean of 15 biopsies was obtained with 18-gauge needles from each liver by alternating biopsies without and with electrocautery. Cautery was performed by applying radiofrequency energy at 25 watts (6 animals) or 125 watts (2 animals) to the needle as the needle was withdrawn from the liver. Blood loss was measured by applying preweighed sponges to the biopsy site, then reweighing them after use. Biopsy specimens were examined by light microscopy. RESULTS: The mean (+/- SD) blood loss was 0.44 g (+/- 1.36 g) with electrocautery and 1.47 g (+/- 2.23 g) without electrocautery (P < .01). No thermal injury was noted in the biopsy specimens when cautery was applied at 25 watts. CONCLUSIONS: The application of radiofrequency current to the biopsy needle after liver biopsy is a feasible and effective method to reduce blood loss in our canine model.

Sonographic and computed tomography characteristics of liver ablation lesions induced by high-intensity focussed ultrasound.

RATIONALE AND OBJECTIVES: The authors have previously demonstrated the ability of high-intensity focused ultrasound (HIFU) to extracorporeally induce selective tissue destruction in the liver without causing damage to the intervening abdominal wall. The potential usefulness of HIFU as a noninvasive therapy for liver cancer has been suggested. This study observes sonographic and computed tomography (CT) characteristics of HIFU-ablated liver tissue in an attempt to assess the possibility of using these imaging methods to monitor the therapeutic results. METHODS: A sonoablated lesion was induced in the liver in each of 20 rabbits with a HIFU therapeutic system. Sequential imaging of the hepatic sonolesions with sonography and CT was performed up to 8 days after treatment, and the imaging patterns were correlated with the histopathology. RESULTS: Hepatic sonoablated tissue could be clearly visualized by sonography as a hypoechoic lesion. On contrast-enhanced CT, the sonolesions were depicted as nonenhanced low-density regions. There was good correlation among the sizes of sonography- and CT-depicted lesions and pathologic specimens. CONCLUSION: In this model, sonography and contrast-enhanced CT were useful imaging modalities for monitoring sonolesion evolution after HIFU treatment.

Percutaneous pulsed-dye laser lithotripsy of gallbladder stones in swine.

Human gallstones were surgically implanted in the gallbladders of 14 pigs. Nine to 16 days later a sheath was successfully placed percutaneously into the gallbladders of 13 animals using ultrasound and fluoroscopy. Two methods were used to guide laser fragmentation: (1) fluoroscopy and a steerable double lumen catheter (two animals), and (2) a flexible endoscope (11 animals). Laser treatment was done in 12 animals with a flashlamp-pumped pulsed-dye laser. A mean of 3600 pulses/animal were delivered using a wavelength of 504 nm and a maximum energy of 60 mJ/pulse. No fragmentation occurred in two animals, partial fragmentation occurred in six, and complete fragmentation occurred in four. Endoscopic guidance was superior to fluoroscopic guidance. Complications (sheath dislodgment, gallbladder perforation, bleeding) occurred in eight of 14 animals. Pulsed-dye laser fragmentation of gallbladder stones is feasible using endoscopic guidance. The use of this technique through an acute percutaneous tract may be associated with complications.

The diagnosis and definition of hepatic malignancies by use of arterial enhanced computerized tomographic scanning.

Axial computerized tomography is a useful tool in the evaluation of either primary or metastatic hepatic neoplasms. An adjunct to this technique is visceral arterial enhanced computerized tomography (AECT). To determine the effectiveness of this modality, bolus intravenous enhanced computerized tomography scans and AECT were compared and correlated to operative findings. Fifty-four consecutive patients were evaluated by AECT and bolus intravenous enhanced computerized tomography over a 30-month period (May 1986 to August 1989) for suspected primary or metastatic hepatic malignancies. Forty-four patients (81%) had hepatic lesions. Fifty-two percent (23 of 44 patients) of the metastatic tumors were from colonic or rectal primary lesions, and 20% were hepatocellular primary lesions. The remainder of the lesions were metastases from a variety of primary lesions. When studies were compared, 34% of the patients (15 of 44 patients) differed in either the location or total number of lesions noted. The lesions of three of the 15 patients (20%) were determined unresectable on the basis of AECT. Of the remaining patients, planned resections were revised in seven patients to either lesser or greater procedures. The number of lesions found at laparotomy equaled the number found by AECT in all but two cases. AECT caused no complications. AECT improved our ability to identify and localize primary and metastatic lesions of the liver. This technique offers the advantage of preoperative definition of the hepatic arterial and portal venous anatomy.

Classification and management of perforations complicating endoscopic sphincterotomy.

BACKGROUND: The management of perforations after endoscopic sphincterotomy (ES) is controversial. The purpose of this study was to analyze the treatments and outcome of patients with ES perforations. METHODS: Between January 1994 and July 1998, in a series of 6040 endoscopic retrograde cholangiopancreatographies, 2874 (48%) ESs were performed: 40 patients (0.6%) with perforation were identified and retrospectively reviewed. RESULTS: All patients (n = 14) with guidewire perforation (group I) were recognized early, managed medically, and discharged after a mean hospital stay of 3.5 days. Twenty of 22 patients with periampullary perforation (group II) were identified early; 18 patients (90%) had aggressive endoscopic drainage, and none required operation. Of the 2 patients identified late, 1 patient required operation and subsequently died. Mean hospital stay for this group was 8.5 days. Only 1 of 4 patients with duodenal perforations (group III) was identified early; all required operation; 1 patient died, and the mean hospital stay was 19.5 days. CONCLUSIONS: ES perforation has 3 distinct types: guidewire, periampullary, and duodenal. Guidewire perforations are recognized early and resolve with medical treatment. Periampullary perforations diagnosed early respond to aggressive endoscopic drainage and medical treatment. Postsphincterotomy perforations diagnosed late (particularly duodenal) require surgical drainage, which carries a high morbidity and mortality rate.

Use of magnetic resonance imaging to determine surgical approach to renal cell carcinoma with vena caval extension.

Extension of renal cell carcinoma into the vena cava is found in 4 to 10 percent of patients. One key to successful surgical management is defining the superior extent of the thrombus. Currently, this is accomplished by using inferior venacavography. The limitations of this imaging technique include difficulty in defining the superior extent of the thrombus and determining the presence of hepatic vein involvement. We report our experience using magnetic resonance imaging (MRI) in 9 patients to stage the thrombus and to determine the operative approach. We believe that MRI supplants other imaging techniques for staging tumor thrombi in renal cell carcinoma.

Testicular ultrasonography after chemotherapy for germ cell neoplasm: significance of highly hyperechoic lesions.

The sonographic appearance of the testis after administration of chemotherapy for metastatic germ cell neoplasm is not well known. Fifty-six patients (60 testes) who were previously treated with chemotherapy for metastatic germ cell neoplasm (originally diagnosed by removal of the contralateral testis or by biopsy of metastatic disease) underwent sonography followed by orchiectomy. The sonographic characteristics found to predict viable intratesticular tumor were: lesion size larger than 5 mm, fewer echoes than adjacent parenchyma (hypoechoic), inhomogeneous echo texture, poor margin definition, cystic areas, or highly hyperechoic foci within a hypoechoic lesion. Fibrosis was predicted by finding single or multiple small, highly hyperechoic lesions. These results suggest the potential for predicting the pathologic diagnosis in some patients after receiving chemotherapy for germ cell neoplasm.

Value of helical computed tomography, angiography, and endoscopic ultrasound in determining resectability of periampullary carcinoma.

BACKGROUND: High-quality preoperative radiographic evaluation is crucial in selecting patients with periampullary carcinomas who are candidates for surgical exploration and tumor resection while minimizing the rate of unnecessary laparotomy. METHODS: Twenty-one consecutive patients were prospectively investigated using helical computed tomography (CT) scanning, endoscopic ultrasonography (EUS), and selective visceral angiography (SVA) to determine tumor resectability. All patients were explored and resectability determined. RESULTS: Helical CT had a sensitivity of 63%, a specificity of 100%, and an overall accuracy of 86%. EUS had a sensitivity of 75%, a specificity of 77%, and an overall accuracy of 76%. SVA had a sensitivity of 38%, a specificity of 92%, and an overall accuracy of 71%. CONCLUSIONS: Helical CT scanning is the best preoperative imaging test to determine tumor resectability. EUS is more sensitive than CT for tumor detection, but underestimates resectability. SVA is no longer helpful in the preoperative evaluation of these malignancies.

Hydrocele of the canal of Nuck: ultrasound appearance.

Swelling in the inguinal region of a woman may result from a number of conditions, including inguinal hernia, tumor (lipoma, leiomyoma, sarcoma), cyst, abscess, adenopathy, or hydrocele of the canal of Nuck. It may be difficult to make a specific diagnosis based upon the history and physical examination alone. This report describes a symptomatic woman in whom ultrasound was helpful in diagnosing a hydrocele of the canal of Nuck, which is the female counterpart of a spermatic cord hydrocele in the male. The ultrasound findings are described.

The role of spiral (helical) computerized tomography with three-dimensional reconstruction in pediatric solid tumors.

The ability to accurately assess tumor size and orientation to surrounding vital structures is an important consideration during preoperative evaluation. The authors report on nine children with solid tumors (hepatoblastoma [1], neuroblastoma [2], adrenal cortical carcinoma [2], liver adenoma [1], primitive neuroectodermal tumor [PNET] [1], and stage V Wilms' tumor [2]) for whom tumor resectability was questioned because of the tumors' close proximity to major blood vessels (noted through conventional radiographic imaging). The children had scanning with spiral volumetric acquisition computerized tomography, (CT) which obtains images during continuous rotation of the x-ray source while the patient moves at a constant velocity through the gantry. This technique is rapid (18 to 30 seconds), and is similar with respect to radiation exposure; little or no sedation is required, and the contrast dose is lower than that of conventional CT. Three-dimensional reconstruction of spiral CT imaging provided useful information that allowed successful resection in all nine cases. The authors suggest that spiral CT may become an important imaging modality in the preoperative evaluation of pediatric solid tumors and that further evaluation of this new methodology is warranted.

Experimental high-frequency ultrasound can detect graft rejection after small bowel transplantation.

Early diagnosis of graft rejection after small bowel transplantation (SBT) can allow prompt institution of vigorous immunosuppressive therapy, with resultant reversal of the rejection process. The current method for graft monitoring is random mucosal biopsy from a stomal site or through an endoscope. However, because early rejection often has a patchy distribution, it could be missed by random biopsy. We hypothesized that the pathological process of rejection would alter acoustic impedance of the tissue and thus change the ultrasonic patterns of the graft intestinal wall. If this hypothesis is correct, then high-frequency endoscopic ultrasound (US) could be used to monitor the entire transplanted bowel and guide the biopsy, with improved yields. This hypothesis was tested in a rat orthotopic SBT model. Sixty-two intestinal specimens (9 isografts, 12 allografts treated with cyclosporine A [CsA], 22 untreated allografts, and 19 intestines from normal rats) were collected for in vitro transluminal US imaging (30 MHz) and histopathologic study. The echo pattern of normal rat intestinal wall consisted of five echo layers that correlated spatially with the histological layers: the innermost hyperechoic layer 1, plus hypoechoic layer 2, corresponded to the mucosa; hyperechoic layer 3, the submucosa; anechoic layer 4, the muscularis propria; and hyperechoic layer 5, the serosa. The isografts and CsA-treated allografts were identical histologically and ultrasonically to normal intestine. However, the echo patterns of the untreated allografts had progressive loss of architectural stratification, with worsening rejection. The change began with patchy indistinctness and disruption of hyperechoic layers 1, 3 and 5, and progressed to total obliteration of the layers, with the intestinal wall becoming a nonstratified hypoechoic structure.(ABSTRACT TRUNCATED AT 250 WORDS)

Spiral CT angiography of the aorta.

Imaging of the aorta and its branches has benefitted greatly from the development of spiral CT techniques, which are relatively fast and noninvasive. The volumetric acquisition of spatial information has permitted the computer to reformat images for inspection of the vessels by several methods from an infinite number of viewing angles. Most aortic diseases-including congenital anomalies, dissection, aneurysm, trauma, inflammation, infection, and thromboembolic disease-can be depicted with this technology. In selected cases, spiral CT may be the only imaging modality needed for the surgical planning of aortic repair. This report discusses the CT angiography technique, its application to a variety of disease states, its role relative to other imaging modalities, and guidelines for patient selection.

Preaortic iliac venous confluence: 2-D and 3-D CT findings.

We report the CT diagnosis of a vascular anomaly of the iliac venous confluence. A preaortic iliac venous confluence is described as demonstrated on 2-D and 3-D computed tomography.

Magnetic resonance imaging in the preoperative assessment of clinical stage I endometrial carcinoma.

Magnetic resonance (MR) imaging may aid in preoperative treatment planning of endometrial carcinoma by accurately estimating tumor volume, depth of myometrial invasion, and extrauterine extension. Preoperative MR scans were obtained on 24 women with clinical stage I endometrial cancer. MR scans were evaluated for uterine size, as an indirect measure of tumor volume, and depth of myometrial invasion. MR detected deep invasion (greater than or equal to 50% of myometrial thickness) with a sensitivity of 71% and specificity of 83% (accuracy 79%) when compared with the pathologic findings. MR staging may assist in deciding which patients should have lymph node dissection at surgery and may aid in decisions regarding adjunctive radiation therapy.

Nuclear medicine evaluation of focal fatty infiltration of the liver.

Focal fatty infiltration of the liver (FFIL) occasionally may be mistaken as metastatic disease, primary liver malignancy, or other space-occupying lesions on CT or ultrasound studies, especially if there is significant mass effect. In these confusing cases, Xe-133 liver imaging has been advocated for confirmation of FFIL, since such studies have been reported to be sensitive and specific. The authors present results of four Xe-133 and four Tc-99m sulfur colloid scans in six patients with FFIL. Xe-133 imaging was found useful for diagnostic confirmation in only one patient and was misleading in the other three. Routine liver-spleen imaging was a more reliable method of confirmation, since no focal defects were found in any of the patients.