Imaging-guided percutaneous biopsy of hepatic masses.

Imaging-guided biopsy of hepatic masses has become the standard for diagnosis. This article reviews the computed tomography, ultrasound, and magnetic resonance imaging characteristics of the more common benign and malignant hepatic masses. This is followed by a description of the procedure from preprocedure work-up to postprocedure care, with a discussion of indications, contraindications, complications, and technique.

The fate of the fibrous capsule after saline implant removal.

After removal of a silicone breast implant, if a capsulectomy is not performed, the residual capsule may persist, become calcified, and appear on routine mammograms. The fate of the capsule around saline implants is less clear. The purpose of this study was to determine the fate of the capsule around saline-filled implants in an animal model. Rats were implanted with 6-ml tissue expanders, which were left in place for 4 months. The implants were then removed and the capsules around the injection port (smooth surface) and tissue expander (textured surface) were examined sequentially. The capsules contracted and dissipated gradually over a year in association with a pericapsular vascular proliferation. It may not be necessary to perform a capsulectomy at the time of saline implant removal.

Bronchioloalveolar cell carcinoma: impact of histology on dominant CT pattern.

The authors set out to determine how histologic variability in bronchioloalveolar cell carcinoma impacts dominant radiographic patterns shown by computed tomography (CT). Thoracic CT's of all patients with pathologically confirmed bronchioloalveolar cell carcinoma diagnosed over a 36-month period were reviewed without knowledge of underlying histologic type. The dominant CT pattern was recorded as 1) air space consolidation; 2) focal nodule or mass; and 3) multicentric nodules or masses. Nodules and masses were further characterized according to borders, distribution, and associated findings, including spiculations and air bronchograms. Histology was independently reviewed. Twenty-seven patients, 16 women and 11 men, mean age 60 years, were diagnosed with bronchioloalveolar cell carcinoma. In 6 (22%) of the 27 cases, the histology was mucinous, with malignant goblet cells identified. Five (83%) of the six mucinous neoplasms manifested as air space consolidation and three (50%) of the six presented with multiple nodules, in which two had coexisting air space consolidation. Of the remaining 21 cases (78%) with nonmucinous histology, the primary malignant cells of origin included Clara cells (n = 8), tall columnar epithelial cells (n = 7) and alveolar type II pneumocytes (n = 6). Sclerosis was a dominant histologic feature in 14 (67%) of the 21 cases. Seventeen (81%) of the nonmucinous neoplasms presented as isolated nodules or masses and four (19%) presented as multiple nodules or masses. Of these four patients with multifocal disease and nonmucinous histology, multiple bronchioloalveolar adenomas accounted for multicentricity in two of the patients. Significant correlations included air space consolidation with mucinous histology (p = 0.001) and focal nodule or mass with nonmucinous histology (p = 0.001). At CT of bronchioloalveolar cell carcinoma, the patterns of air-space consolidation correlate with mucinous histology and isolated nodules or masses with nonmucinous histology. The pattern of multiple nodules or masses, however, did not correlate with histology. Coexisting bronchioloalveolar adenomas can contribute to apparent multicentric disease in patients with nonmucinous histology.

Distal radial artery lesion as a source of digital emboli.

Ischemic changes of the digits caused by emboli are rare. When they do occur, the typical sites of origin include the heart, the proximal subclavian artery, and the thoracic outlet. Dialysis access or iatrogenic injuries may be a more distal source of emboli. Two patients, each with embolization to the thumb and index finger from a lesion in the anatomical snuff-box, were studied. Neither patient had any other atherosclerotic occlusive disease, and both lesions occurred precisely where the extensor pollicis longus crossed the artery and would be expected to compress it against the proximal epiphysis of the first metacarpal when the hand was closed. These lesions were excised, and bypass was performed, with rapid resolution of symptoms. This is an unusual cause of digital embolization that should be considered in patients with emboli to the thumb and index finger.

CT angiogram sign: incidence and significance in lobar consolidations evaluated by contrast-enhanced CT.

OBJECTIVE: The CT angiogram sign--that is, the ability to see normal pulmonary vasculature within parenchymal consolidations--was initially reported as specific for the diagnosis of bronchioloalveolar cell carcinoma. Our purpose was to establish the frequency of this sign in lobar consolidations of varied causes as revealed by contrast-enhanced CT. We also sought to determine if the presence of this sign contributed to the specificity of radiographic diagnosis. MATERIALS AND METHODS: All consecutive contrast-enhanced thoracic CT examinations performed for evaluation of lobar consolidations between May 1994 and April 1997 were reviewed. The CT angiogram sign was considered present when segments of pulmonary vessels could be identified within alveolar consolidations. Medical records were reviewed to establish the causes of the consolidations. RESULTS: Fifty-one patients (24 women, mean age = 59 years; 27 men, mean age = 46 years) had lobar or multilobar consolidations due to pneumonia without central obstruction (n = 20), pneumonia or pneumonitis with central obstruction (n = 19), passive atelectasis (n = 7), and (one case each) mucus plugging, lipoid pneumonia, pulmonary lymphoma, bronchioloalveolar cell carcinoma, and pulmonary hemorrhage. The CT angiogram sign was present in 15 (29%) of 51 consolidations, including seven (37%) of 19 postobstructive consolidations, four (20%) of 20 cases of pneumonia without central obstruction, one (14%) of seven cases of passive atelectasis, and each single case of lymphoma, bronchioloalveolar cell carcinoma, and lipoid pneumonia. CONCLUSION: The CT angiogram sign is a common finding in lobar consolidations evaluated by contrast-enhanced CT. However, the sign does not add specificity to the radiographic diagnosis.

High-resolution CT in the acute exacerbation of cystic fibrosis: evaluation of acute findings, reversibility of those findings, and clinical correlation.

OBJECTIVE: The aims of this study were threefold: to compare high-resolution CT (HRCT) of adult patients with cystic fibrosis (CF) during acute exacerbations with asymptomatic patients with CF, to evaluate reversibility of HRCT abnormalities after exacerbations, and to correlate HRCT with clinical parameters. SUBJECTS AND METHODS: Nineteen symptomatic and eight asymptomatic patients were prospectively evaluated by HRCT and pulmonary function tests (PFTs). Symptomatic patients were reassessed 2 weeks after the exacerbation. Studies were independently reviewed by two radiologists using a modified Bhalla scoring system, noting the presence, extent, and severity of bronchiectasis, peribronchial thickening, mucus plugging, and atelectasis or consolidation. Modifications to the Bhalla system included evaluation of the presence and profusion of centrilobular nodules and air-fluid levels within bronchiectatic cavities. The highest possible score was 24 points. Higher scores indicated greater severity. Mosaic perfusion was noted but not included in the modified Bhalla HRCT score. Total modified Bhalla HRCT score and components of the HRCT score were correlated with corresponding PFT parameters. RESULTS: Bronchiectasis, peribronchial thickening, mucus plugging, centrilobular nodules, and mosaic perfusion were identified in symptomatic and asymptomatic patients. Air-fluid levels in bronchiectatic cavities, identified in two patients, represented the only finding limited to acute exacerbation. Reversible findings included air-fluid levels (100%), centrilobular nodules (36%), mucus plugging (33%), and peribronchial thickening (11%). Total HRCT severity scores of symptomatic and asymptomatic patients correlated with forced vital capacity (FVC) (r = .44, p = .01) and forced expiratory volume at 1 sec (FEV1) (r = .34, p = .04). Severity of bronchiectasis correlated with FVC (r = .50, p = .004) and FEV1 (r = .40, p = .02). Mucus plugging and centrilobular nodules did not correlate with PFT parameters. In the symptomatic patients, improvement in HRCT score correlated with changes in FEV1/FVC (r = .39, p = .049). CONCLUSION: Air-fluid levels in bronchiectatic cavities were the only parenchymal finding shown by HRCT that was limited to the acute exacerbation of CF in our study population. However, this finding was rare, being seen in two of 19 patients. Mucus plugging, centrilobular nodules, and peribronchial thickening were potentially reversible findings in symptomatic patients. HRCT accurately revealed disease severity in patients with CF. We also found that changes in HRCT scores correlated with clinical improvement as determined by PFTs.

Necrotizing fasciitis: CT characteristics.

PURPOSE: To establish computed tomographic (CT) criteria for the diagnosis of necrotizing fasciitis. MATERIALS AND METHODS: Twenty CT scans in 20 patients with pathologically proved necrotizing fasciitis were reviewed retrospectively for fascial thickening, fat infiltration, focal fluid collection, soft-tissue gas, muscle involvement, and intra-abdominal extension; the findings were correlated with clinical factors, including associated illnesses, disease site, treatment, and outcome. RESULTS: Average patient age was 57.8 years; there were 13 men and seven women. Four patients (20%) died. Asymmetric fascial thickening and fat stranding were seen in 16 patients (80%). Gas tracking along fascial planes was present in 11 patients (55%), and abscesses were found in seven patients (35%). Infection sites were scrotum (n = 6), a lower extremity (n = 4), perineum (n = 4), neck (n = 2), back (n = 2), arm (n = 1), and abdomen (n = 1). Underlying illness (n = 17) was diabetes in 10 patients (50%), alcoholism in three (15%), chronic renal failure in two (10%), and drug abuse in two (10%). CONCLUSION: CT criteria of asymmetric fascial thickening and gas are valuable in assessing suspected necrotizing fasciitis. CT also can provide information on coexistent deep collections.

Interpretation of chest radiographs in AIDS patients: usefulness of CD4 lymphocyte counts.

Specific infections and neoplasms that are complications of acquired immunodeficiency syndrome (AIDS) occur within various CD4 lymphocyte count ranges. Knowledge of how these counts correlate with radiographic appearances of these entities can limit the differential diagnosis because certain conditions are uncommon above a specific count. In patients with CD4 lymphocyte counts above 200 cells/mm3 and radiographic findings of cavitary and noncavitary consolidation, bacterial pneumonia and Mycobacterium tuberculosis are the major diagnostic considerations. As the CD4 lymphocyte count falls, these infections are still common; however, cavitation is seen less frequently with Mycobacterium tuberculosis, and unusual bacterial infections, including those caused by Rhodococcus equi and Nocardia asteroides, should be considered. In patients with counts below 200 cells/mm3, Pneumocystis carinii pneumonia is the most common infection, usually manifesting radiographically as a reticular interstitial pattern. At CD4 lymphocyte counts of 50-200 cells/mm3, disseminated fungal infection and Kaposi sarcoma become prevalent. In patients with advanced AIDS and counts below 50 cells/mm3, radiographic nodular or reticular patterns may indicate AIDS-related lymphoma and cytomegalovirus and Mycobacterium avium-intracellulare infections. When CD4 lymphocyte counts are applied to interpretation of chest radiographs in AIDS patients, the working differential diagnosis of a radiographic pattern can be tailored to the clinical situation of a given patient.

Differential density of normal renal parenchyma on nonenhanced CT: a new observation.

PURPOSE: Nonenhanced CT scans through the kidneys commonly show a difference in radiopacity between the inner peripelvic portion of the renal parenchyma and the more peripheral regions of the renal parenchyma. This normal observation has not been described. METHOD: We reviewed 50 nonenhanced CT scans. Renal parenchyma was evaluated by both visual inspection and density measurements of inner and outer aspects of the kidneys in 38 and visual inspection only in 12. A narrower window was used to better show density differences (100 W, 35 L). We recorded the indication for the CT, history, and recent blood chemistries. RESULTS: The inner parenchyma was of greater radiopacity than the outer parenchyma in 35 of 50 cases by visual inspection and in all densitometry cases (38 of 38). There was no correlation with clinical history or blood chemistry. CONCLUSION: A difference in density between the inner and outer portions of the renal parenchyma is very common and will often be seen if one looks for it. We have not shown an etiology for this difference, and indeed, it may be physiological. One must be aware of this finding to avoid mistaking it for pathology.

Case report: ultrasound and MRI findings in a scrotal epidermoid cyst.

Intrascrotal masses in the adult are worrisome due to their possible malignancy. Most intratesticular masses are malignant whereas most extratesticular masses are benign. The differential diagnosis of intrascrotal cysts usually includes simple testicular cysts, intratesticular epidermoid and dermoid cysts, tunica albuginea cysts, epididymal cysts and spermatoceles [1-7]. This case report describes a large epidermoid cyst of the scrotum presenting as an enlarging scrotal tumour.

Pulmonary complications of cystic fibrosis in adults.

The demographics of cystic fibrosis (CF) are continuously changing, with adults representing a growing percentage of the patient population, which is expected to reach 50% by the year 2000. Pulmonary complications are primarily responsible for the high morbidity and mortality in this disease. Although the radiographic findings are quite specific, the correct diagnosis may not be suggested in the adult patient because of a lack of familiarity with its pulmonary manifestations in this age group. High-resolution CT (HRCT) has contributed to our understanding of the radiographic findings, especially at the level of the small airways. The role of imaging, including chest radiography and HRCT, is discussed. Issues that remain controversial include imaging in the acute pulmonary exacerbation, and the routine use of imaging as part of clinical scoring and in monitoring responses to new treatment modalities.

The radiology of inflammatory bowel disease.

This article presents various imaging modalities, including plain films, ultrasonography, magnetic resonance imaging, and radionuclide imaging, used for the diagnosis of inflammatory bowel disease (IBD), ulcerative colitis (UC), and Crohn's disease (CD). Also discussed are how to distinguish UC from CD and some of the intestinal complications of IBD.

Carcinoid of the intrahepatic ducts.

Carcinoid tumors of the biliary tree are rare. To the best of our knowledge, this is the first reported case of an intrahepatic ductal carcinoid and the thirteenth reported case of biliary carcinoid. The radiographic appearance is variable. A brief review of the previously described cases is presented.

Radiocontrast-associated renal dysfunction: incidence and risk factors.

Contrast-induced nephropathy is a potentially serious untoward reaction to radiologic contrast media. The incidence of this nephropathy and the predisposing conditions are not well established, possibly because of methodologic differences between studies. We evaluated the incidence of contrast-induced nephropathy after femoral arteriography in 394 patients by using multiple definitions (different increases in serum creatinine or blood urea nitrogen levels at various times). When an increase in the level of serum creatinine of greater than 0.3 mg/dl and greater than 20% on day 1, 2, or 3 and on day 5, 6, or 7 was used to define the disorder, the incidence in our group of patients was 10% for nonazotemic patients vs 30% for azotemic patients (p less than .001); 2% for nondiabetic, nonazotemic patients vs 16% for diabetic, nonazotemic patients (p = .003); and 38% for patients who were both diabetic and azotemic vs 16% for diabetic, nonazotemic patients (p = .022). Baseline renal insufficiency and diabetes mellitus (especially when insulin dependent) were significant predisposing factors. The effects of dehydration and increased volume of contrast medium on the incidence of contrast-induced nephropathy were not clear; the age and sex of the patient were not important risk factors. The incidence of contrast-induced nephropathy depends on the definition used. Although contrast-induced nephropathy may develop in any patient, diabetes, renal insufficiency, and, possibly, dehydration and dose of contrast medium are risk factors.

Radiocontrast-associated renal dysfunction: a comparison of lower-osmolality and conventional high-osmolality contrast media.

Nephropathy is an established untoward event associated with intravascular administration of conventional high-osmolality contrast media (HOM). It has not been shown previously that lower-osmolality contrast media (LOM) are less nephrotoxic in a clinical setting. We evaluate the ability to replace HOM with LOM (in lower-extremity angiography) to reduce the incidence of nephropathy. We use multiple definitions for contrast-induced nephropathy (six different magnitudes of rise of serum levels of creatinine or blood urea nitrogen in various periods). The incidences of nephrotoxic effects with LOM vs HOM in patients with presumed risk factors, including preexisting renal insufficiency and diabetes, are evaluated also. When all patients are considered, the incidence of contrast-induced nephropathy for LOM vs HOM (defined as an increase in serum creatinine level greater than 0.3 mg/dl and greater than 20% on day 1, 2, or 3 and on day 5, 6, or 7, is 7% vs 26% (p = .001). When only patients with preangiography azotemia are considered, the incidence of contrast-induced nephropathy for LOM vs HOM is 10% vs 41% (p = .017); for diabetic patients, regardless of preangiography creatinine level, the incidence is 10% vs 31% (p = .012). Although contrast-induced nephropathy may develop even in a patient with no risk factors who receives LOM, LOM is associated with a decreased incidence of this condition, to various degrees, depending on the presence of risk factors.

Diagnostic imaging in puerperal febrile morbidity.

This retrospective study was conducted to assess the value of imaging in patients with refractory puerperal febrile morbidity. During a 36-month period, 31 patients were referred for ultrasound and/or computed tomography or magnetic resonance imaging because of postpartum fever unresponsive to broad-spectrum antibiotic therapy of at least 72 hours' duration. Hematomas were identified in 11 women. Abscesses were diagnosed in seven patients, ovarian venous thrombosis in two, vesicouterine fistula in one, small-bowel obstruction in one, and a subcutaneous seroma in one. Twenty-one women had endomyometritis, 13 of whom also had other extrauterine abnormalities (abscess in six, hematoma in four, and ovarian venous thrombosis, vesicouterine fistula, and small-bowel obstruction in one each). Retained placental tissue was found in two women with endomyometritis. Only two subjects had negative imaging studies. In most patients, imaging led to definitive diagnosis and specific therapeutic measures resulting in resolution of the febrile morbidity. Our experience suggests that these imaging techniques may be helpful in evaluating puerperal fever.

Hemodynamic effects of octreotide in patients with autonomic neuropathy.

BACKGROUND: The somatostatin analogue, ectrootide, is being used to treat postprandial hypotension in patients with autonomic neuropathy. Although the therapeutic effect of the drug is presumably secondary to a splanchnic vasoconstrictor action, its effect on splanchnic hemodynamics has never been characterized in patients with autonomic neuropathy. Moreover, it is unknown whether octreotide acts on other vascular beds in this group of patients or whether it affects cardiac output. We, therefore, measured splanchnic, forearm, and systemic vascular resistance and cardiac output before and after administering octreotide (0.4 microgram/kg s.c.) to patients with idiopathic autonomic neuropathy and diabetic autonomic neuropathy. METHODS AND RESULTS: Splanchnic blood flow was determined from the clearance of indocyanine green in seven patients. We observed that octreotide decreased splanchnic blood flow (from 850 +/- 77 to 664 +/- 48 ml/min, p less than 0.005), increased mean blood pressure (from 97 +/- 6 to 115 +/- 3 mm Hg, p less than 0.005), and increased splanchnic vascular resistance (from 0.118 +/- 0.012 to 0.18 +/- 0.018 mm Hg/ml/min, p less than 0.005). Forearm blood flow was measured by plethysmography in 13 patients. Octreotide increased forearm vascular resistance in patients with idiopathic autonomic neuropathy (n = 8) from 19.1 +/- 1.0 to 27.2 +/- 3.8 mm Hg/ml/min/100 ml forearm volume (p less than 0.01) and from 25.2 +/- 3.9 to 41.0 +/- 6.8 mm Hg/ml/min/100 ml (p less than 0.01) in patients with diabetic autonomic neuropathy (n = 5). Cardiac output was measured by two-dimensional echocardiography. Octreotide administration increased cardiac output in five of six patients with idiopathic autonomic neuropathy (from 4.4 +/- 0.4 to 5.0 +/- 0.5 l/min, p less than 0.02) and five of five patients with diabetic autonomic neuropathy (from 3.8 +/- 0.4 to 5.1 +/- 0.4 l/min, p less than 0.02). Systemic vascular resistance increased in patients with idiopathic autonomic neuropathy from 21.2 +/- 2 to 24.9 +/- 2.6 (p less than 0.05) but did not change in patients with diabetic autonomic neuropathy. CONCLUSION: The pressor effect of octreotide in patients with autonomic neuropathy is associated with increased splanchnic and forearm vascular resistance and with increased cardiac output.