Infectious imaging with indium-111-labeled nonspecific polyclonal human immunoglobulin.

Nonspecific polyclonal immunoglobulin (IgG), prepared from pooled human serum gamma globulin and labeled with 111In has been reported to be equivalent to antigen-specific antibody in the detection of focal infection or inflammation during the first 24 hr after injection. We describe our experience in a Phase II clinical study using 111In-IgG in 15 patients (8 males, 7 females) ranging from 26 to 80 (mean = 50) yr of age with suspected focal infection/inflammation. Pathologic confirmation was obtained in 5/15 cases. A combination of clinical course, laboratory results, and other imaging procedures were used to categorize the other 10 patients. One possible false-negative involved a presumed aspiration pneumonia in a patient with a history of aspiration, bibasilar infiltrates on chest film, and no other identified source of infection. Otherwise, there were 10 confirmed positives, 4 confirmed negatives, and no false-positives. Our findings confirm earlier reports that 111In-IgG may be a superior imaging agent for infection/inflammation with practical advantages over 67Ga-citrate and 111In-labeled leukocytes.

Biliary complications of gallstone lithotripsy detected by Tc-99m DISIDA scintigraphy.

Extracorporeal shock wave lithotripsy (ESWL) has been reported to be a safe and relatively effective non-invasive treatment for radiolucent gallbladder calculi in selected patients. Ideally, the goal of successful treatment is the passage of all fragments from the gallbladder into the intestinal tract. Biliary colic has been reported in up to 35% of treated patients, although complications such as cholecystitis, cholangitis, common bile duct obstruction, and pancreatitis are surprisingly infrequent. Cholescintigraphy is the procedure of choice in patients with biliary colic and suspected acute cholecystitis. It has proven to be more sensitive than ultrasound in detecting acute common bile duct (CBD) obstruction, since functional obstruction precedes morphologic dilatation of the CBD. This report reviews two cases of post-lithotripsy cystic and common duct obstruction and discusses the role of Tc-DISIDA scintigraphy following gallstone ESWL.

Bronchobiliary fistula detected by cholescintigraphy.

We present a case of a bronchobiliary fistula initially detected by hepatobiliary scintigraphy. The patient developed bilioptysis 18 mo after undergoing a right hepatic lobectomy and resection of the common bile duct for cholangiocarcinoma. The procedure was complicated by the development of a subphrenic abscess that required percutaneous biliary drainage.

Ventilation-perfusion scintigraphy in an adult with congenital unilateral hyperlucent lung.

A variety of congenital and acquired etiologies can give rise to the radiographic finding of a unilateral hyperlucent lung. An unusual case of congenital lobar emphysema diagnosed in a young adult following the initial discovery of a hyperexpanded, hyperlucent lung is reported. Although subsequent bronchoscopy and radiologic studies detailed extensive anatomic abnormalities, functional imaging also played an important role in arriving at this rare diagnosis. In particular, ventilation-perfusion scintigraphy identified the small contralateral lung as the functional lung and helped narrow the differential diagnosis to etiologies involving obstructive airway disorders.

Multimodality imaging of a pancreatic transplant. A case report.

A 41-year-old man who had insulin-dependent diabetes mellitus from the age of 14 underwent cadaveric renal transplant in 1984. Two years later, the patient underwent pancreatic allograft transplantation. The patient did well for eight days after the operation and did not require exogenous insulin. After the eighth day, serum glucose levels rose. Multiple radiologic studies were performed to assess the possibility of graft rejection. A Tc-99m DTPA study revealed a gradual decrease in perfusion, and an In-111 oxine WBC study showed nonspecific inflammation. CT scanning and MRI displayed postsurgical anatomical relationships and excluded a peripancreatic fluid collection, but were unable to demonstrate parenchymal abnormality of the pancreas. Tests for infection proved negative. Because the decreased blood flow demonstrated by DTPA study indicated transient ischemia, the patient was treated for graft rejection and stabilized quickly.

In vivo SPECT imaging of CNS D-2 dopamine receptors: initial studies with iodine-123-IBZM in humans.

Iodobenzamide (IBZM) is a D-2 dopamine receptor antagonist. In this paper the results of Phase I clinical studies of iodine-123-(123I)IBZM in humans are reported. Preliminary imaging studies, both planar and single-photon emission tomography (SPECT), of no-carrier added [123I]IBZM in humans show specific localization in the basal ganglia of the brain. At 2 hr after an i.v. injection, the brain uptake was 3.72% of the dose, and at 20 hr later the uptake diminished to 0.7%. Radiation dosimetry calculation indicated that the radiation dose to the brain was minimum, 0.039 rad/mCi, while the large intestine wall received the highest dose, 0.28 mrad/mCi. The radiation dosimetry and pharmacology data suggest that this agent is safe for human use.

Chronic complicated osteomyelitis of the lower extremity: evaluation with MR imaging.

Preoperative magnetic resonance (MR) imaging examinations were performed with a 1.5-T superconducting magnet in 14 patients who had extensive deformities of the bones and soft tissues of the lower extremities due to previous trauma, surgery, and chronic infection. This retrospective study assessed the diagnostic performance of MR imaging in determining the presence and extent of active bone and soft-tissue infections. The presence and extent of active osteomyelitis were confirmed by reviewing the clinical, surgical, histologic, and microbiologic records of all patients. Of the 14 MR imaging examinations, 11 were true-positive, two were true-negative, one was false-positive, and none was false-negative. In the indium scans obtained in this group of patients, five were true-positive, three were true-negative, none was false-positive, and three were false-negative. In two amputated extremities, close correlation was found between the extent of disease seen on surgical and pathologic examination and that demonstrated by MR imaging, which could delineate the course of sinus tracts. MR imaging was therefore helpful in assessing the activity of chronic complicated osteomyelitis and beneficial in surgical planning for these patients.

Effects of collateral blood vessel ligation and electrical conditioning on blood flow in dog latissimus dorsi muscle.

Utilization of skeletal muscle as a myocardial substitute requires it to undergo two major modifications: mobilization to the site of action and adaptation to continuous activity. We have examined the effects of collateral blood vessel ligation, which would accompany mobilization, on blood flow in control and electrically conditioned canine latissimus dorsi (LD) muscle. Blood flows were measured at rest and during a vigorous isometric fatigue test. In 22 control muscles, electrical stimulation during the fatigue test resulted in a sevenfold increase in muscle blood flow (0.26 +/- 0.18 ml/g/min at rest, 1.69 +/- 0.84 ml/g/min during stimulation). No difference was detected in flow to distal and proximal portions of the muscle. In three muscles where collateral vessels were ligated immediately before measurement of blood flow, flow in the proximal portion of the muscle was not significantly different from control, but in the distal portion, stimulation failed to elicit an increase in flow (0.12 +/- 0.13 ml/g/min at rest, 0.16 +/- 0.07 ml/g/min during stimulation). In animals allowed a 3-week recovery period following collateral vessel ligation, stimulation-induced increases in blood flow were detected but remained lower than control. Muscles which had been conditioned by continuous electrical stimulation for 6-7 weeks at 2 or 10 Hz generated less peak isometric tension than controls (peak tension = 4.5 +/- 1.7 kg control, 2.4 +/- 0.7 kg following 2 Hz conditioning, 1.6 +/- 0.4 kg following 10 Hz conditioning). However, these muscles demonstrated an increased resistance to fatigue.(ABSTRACT TRUNCATED AT 250 WORDS)

Osteogenic sarcoma with pulmonary metastasis visualized by bone imaging.

Extraosseous soft tissue metastases from osteosarcoma occasionally accumulate Tc-99m MDP. The authors present a case of osteogenic sarcoma of the femur with a pulmonary metastasis detected by bone imaging with radiographic correlation including CT and magnetic resonance imaging. The implication of the detection of osseous and extraosseous metastasis in these patients by bone imaging is discussed. The changing role of bone imaging in the initial workup and follow-up of patients with osteogenic sarcoma is reviewed in light of the change in course and prognosis of the disease as a result of recent advances in adjuvant chemotherapy.

The effect of meal energy content on gastric emptying.

Gastric emptying (GE) has been reported to be influenced by meal weight (grams) and composition (% carbohydrate:protein:fat) but the effect of meal energy content (kcal) on gastric emptying, independent of composition, has not been thoroughly investigated by scintigraphic techniques. In order to determine the effect of caloric content on GE, 12 normal male volunteers, ranging in age from 19-28 yr (mean = 24 yr), had GE scans (n = 32) performed with a solid meal of fixed composition (carbohydrate 40%:protein 40%:fat 20%) but varying energy content [150 kcal (n = 9), 300 kcal (n = 14), and 600 kcal (n = 9)]. Increasing the energy content of the meal of fixed composition progressively delayed gastric emptying: T1/2 = 57', 70', and 95' for 150 kcal, 300 kcal and 600 kcal, respectively (p less than 0.05; Student's t-test). Reproducibility, evaluated by performing GE scans (n = 8) on different days in the same individual (n = 4) with the same meal (300 kcal), was good (r greater than or equal to 0.89). Variability varied inversely with meal energy content (CV:150 kcal greater than or equal to 300 kcal and 600 kcal). The 300 kcal mean seems to be the best compromise since it results in less intersubject variability than 150 kcal, has minimal intrasubject variability, but is not as prohibitively large as the 600 kcal meal.

The clinical utility of the Tc-99m SC intraperitoneal scan in CAPD patients.

The intraperitoneal instillation of dialysate increases intra-abdominal pressure and consequently predisposes to subcutaneous infiltration, leaks, and herniations through defects in the abdominal wall. In this setting, the incidence of abdominal hernias ranges between 9% and 24%. Life-threatening complications (incarceration/strangulation) occur in up to 13.2% of hernias. Therefore, the authors evaluated the efficacy of the Tc-99m sulfur colloid (SC) intraperitoneal scan in the detection of abdominal leaks and hernias in 11 continuous ambulatory peritoneal dialysis (CAPD) patients over a 2-year period at the Hospital of the University of Pennsylvania. Eleven patients (7M, 4F) ranging in age from 24 to 72 (mean = 50.8), on CAPD, were evaluated for clinically suspected abdominal hernias or dialysate leaks with intraperitoneally administered Tc-99m SC. After the injection of 3-5 mCi of Tc-99m into a standard 2 liter dialysate bag, multiple sequential anterior images of the abdomen were obtained in the supine position over the course of one hour. Delayed images were obtained after ambulation and post-drainage two or more hours postinjection in multiple projections and positions in order to demonstrate any abnormal focal accumulations of fluid to the best advantage. Any detected abnormalities were marked and correlated with the physical examination and the patient's symptoms. Two patients had normal scans. Of the nine abnormal scans, five hernias were identified in four patients and six leaks were detected in the other five patients.(ABSTRACT TRUNCATED AT 250 WORDS)

Effect of the Garren-Edwards gastric bubble on gastric emptying.

The Garren-Edwards Gastric Bubble (GEGB) was introduced in 1984 as an alternative to surgery (jaw wiring, gastrointestinal bypass, vertical banded gastroplasty) for the treatment of morbid obesity in patients who had failed behavior modification therapy or dietary management for weight reduction. Its mechanism of action is unclear and previous reports have not demonstrated any significant consistent alteration in gastric emptying (GE) as measured by radionuclide techniques. Other proposed mechanisms include: placebo, hormonal, mechanical "satiety", behavioral modification, and neuronal. In order to determine the effect of the GEGB on GE, ten obese (mean % overweight = 89%) patients, 27-50 yr old (mean = 36 yr), had solid GE scans before and 5 wk after endoscopic placement of the bubble. GE scans were performed in six patients after removal (12 = wk residence time). The meal consisted of 300 microCi [99mTc]sulfur colloid in the form of a 300 kcal egg sandwich (egg white 248 g, white bread 40 g, butter 6 g; composition = CHO 40:PR 40: FAT 20) with 180 ml deionized water. Images were obtained in the anterior and posterior projections at 15-min intervals for 1 hr (four patients) or 2 hr (six patients) and the %GE (decay corrected geometric mean) was calculated. Unlike other studies involving the GEGB, adjunctive therapy in the form of dieting and behavior modification were not employed in this study. The effect of the GEGB alone in the treatment of obesity has not been previously evaluated. There was a significant (p less than 0.025) delay in gastric emptying at 1 hr (pre-bubble mean % gastric retention = 46%; bubble mean = 57%; n = 10). After removal, GE returned toward baseline (mean % gastric retention = 51%; n = 6) (p less than 0.05) (Student's t-test). The average weight loss was 5.5 lb (n = 10; p less than 0.025). One mechanism of action of the GEGB may be delayed gastric emptying resulting in early satiety and decreased food intake with resultant weight loss.

Acute gangrenous cholecystitis due to metastatic melanoma detected by cholescintigraphy.

A case of acute gangrenous cholecystitis due to cystic duct obstruction by a metastasis from malignant melanoma detected by cholescintigraphy is presented.

Localization of pheochromocytoma: MIBG [correction of MIGB], CT, and MRI correlation.

Nineteen patients (8 M, 11F) ranging in age from 15 - 67 yr old (mean = 39 yr) with clinically diagnosed pheochromocytomas were prospectively evaluated with 131I metaiodobenzyl-guanidine (MIBG) scintigraphy (n = 19), computed tomography (CT) (n = 19), and magnetic resonance imaging (MRI) (n = 17) in order to determine their relative diagnostic efficacy. Pathologic confirmation was obtained in all 19 patients: 13 intraadrenal and six extraadrenal with metastases in five (Table 1). All three imaging modalities were in agreement in 11 of 14 completed examinations (79%). MIBG and CT agreed in 16 of the 19 patients in whom both were performed (84%). MIBG/MR and CT/MR results were concordant in 12 of 14 (86%) and 13 of 14 (93%) jointly completed examinations, respectively. There was one false-negative (FN) MIBG scan, two FN CT scans, and one FN MR scan. MIBG, CT, and MRI are complementary procedures with MIBG providing more specific functional information and the latter two superior anatomic detail. MIBG scintigraphy is recommended as the initial localizing study of choice (especially for the detection of extraadrenal disease and postoperative recurrence), as a guide for CT and/or MR and specific functional confirmation of their findings. Although MRI is capable of imaging in multiple planes (without exposure to ionizing radiation or the need for i.v. contrast material) with superior contrast compared to CT, it is expensive and has poor patient cooperation. However, it may be capable of differentiating pheochromocytomas from other adrenal masses on the basis of signal characterization.

Limited weight losses with a gastric balloon.

An evaluation of the Garren-Edwards gastric bubble in the treatment of obesity was done. Several clinical trials have compared the effects of behavior therapy with and without the bubble, but the effects of the bubble alone have not been previously evaluated. Ten obese women averaging 91% overweight received the bubble without adjunctive therapy during a 12-week treatment period. Frequent psychological and laboratory measures as well as weight were obtained during the study to explore the possible mechanisms of the bubble's effect and its side effects. Mean weight change was -2.5 kg, with a range of -8.8 to +1.6 kg. Four patients lost more than 3.5 kg, three lost less than 3.5 kg, and three gained weight. The Garren-Edwards gastric bubble alone does not appear to provide significant benefit to most obese patients.

Reversible acute unilateral diminished pulmonary ventilation and perfusion caused by a mucous plug.

A case of acute unilateral decreased pulmonary ventilation and perfusion caused by a mucous plug documented by bronchoscopy is presented, and the literature is reviewed.

Nonthromboembolic causes of high-probability lung scans.

Three cases of high-probability lung scans because of nonthromboembolic causes (dissecting thoracic aortic aneurysm, sarcoid with venous occlusion, and subclavian catheter misplacement) are presented along with a review of the literature.

Rapid resolution of massive pulmonary embolism due to streptokinase therapy: documented by ventilation/perfusion imaging.

A case of massive pulmonary embolism is presented, with dramatic complete resolution within 36 hours due to anticoagulant and lytic therapy, documented by perfusion scintigraphy.

Renal allografts: prospective analysis of Doppler sonography.

Fifty-six consecutively transplanted renal allografts were prospectively evaluated with serial Doppler sonographic examinations. Thirty-eight episodes of transplant rejection in 32 patients (63% proved pathologically) and 24 episodes of acute tubular necrosis (ATN) in 24 patients were encountered. The Doppler spectral waveform was characterized by means of the pulsatility index (PI), systolic/diastolic ratio (SDR), diastolic/systolic ratio (SDR), diastolic/systolic ratio (DSR), and resistive index (RI). Accuracy was optimized with use of top normal values as follows: PI = 1.8, SDR = 4.0, DSR = 0.25, RI = 0.75. There were no significant differences in the indices for those patients undergoing rejection versus those with ATN. The sensitivity for predicting transplant rejection was adversely affected by the history of either ATN or a previous rejection episode in the same allograft. Comparison with concurrent radionuclide examinations revealed similar sensitivities for rejection with scintigraphy and sonography. Differentiation of ATN from rejection was more reliable with scintigraphy than with sonography.