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Hongming Zhuang

Publications and source records attributed to Hongming Zhuang.

88 records · Page 5Linked to original sources
PubMed2002

The receiver operating characteristic curve for the standard uptake value in a group of patients with bone marrow metastasis.

PURPOSE: The aim of this work was to determine the standard uptake value (SUV) threshold for differentiating malignant from benign bone lesions. MATERIAL AND METHODS: Ninety-nine bone sites in 33 patients who had undergone a 2-deoxy-2-[18F]fluoro-D-glucose-positron emission tomography (FDG-PET) study for cancer evaluation were studied. In addition to FDG-PET, a bone scan and at least two of the following determinations: magnetic resonance imaging (MRI), computed tomography (CT), and x-ray were conducted in each patient. The bone lesions were considered positive for malignancy if confirmed by clinical follow-up or a high degree of suspicion based on the positive results of at least three (which must include bone scan) out of four other imaging modalities. By these criteria, 39 lesions were considered positive and 60 were considered negative. The SUV values were classified as positive or negative using 61 different values of threshold (range from 1.0 to 7.0). These results were compared with the positive criteria above and reclassified as true positive, true negative, false positive, and false negative. The true-positive fraction and false-positive fraction were calculated for each threshold value. The receiver operating characteristic (ROC) curve was drawn and the best value was determined by visual analysis. RESULTS: The SUV threshold was considered 2.5. Twenty-nine out of 39 bone lesions classified as positive showed a SUV > 2.5. Of the 10 false-negative lesions, seven showed a SUV between 1.1 and 2.0, and three were not detected. Fifty-six out of 60 lesions classified as negative showed a SUV < 2.5. Four lesions were false positive: one was a rib fracture and three were severe degenerative changes in the lumbar spine. Using an SUV threshold of 2.5, the sensitivity was 74.3% and the specificity was 93.3%. CONCLUSION: In our patient population, the optimal SUV to classify a bone lesion as malignant or benign is 2.5.

Journal Article↗
PubMed2002

2-Deoxy-2-[18F]fluoro-D-glucose positron emission tomography monitoring disease progress in a patient with islet carcinoma of the pancreas.

A woman with islet cell carcinoma of the pancreas proven by biopsy at an exploratory laparotomy underwent six cycles of chemotherapy with paclitaxel and carboplatin. After the chemotherapy to monitor her primary tumor and hepatic metastases, she had three consecutive 2-deoxy-2-[18F]fluoro-D-glucose positron emission tomography (FDG-PET) determinations that correlated with an In-111 octreotide single photon emission computer tomography. FDG-PET might have utility in monitoring islet cell carcinoma of the pancreas in evaluating metabolic changes following chemotherapy.

Journal Article↗
PubMed2002

Positron emission tomography imaging in nonmalignant thoracic disorders.

The role of the fluorodeoxyglucose (FDG) technique positron emission tomography (PET) is well established in the management of patients with lung cancer. Increasingly, it is becoming evident that FDG-PET can be effectively employed to diagnose a variety of benign pulmonary disorders. Knowledge of such applications further expands the domain of this powerful modality and further improves the ability to differentiate benign from malignant diseases of the chest. We describe pertinent technical factors that substantially contribute to optimal imaging of the thoracic structures. Particularly, the complementary role of attenuation correction (AC) to that of non-AC images is emphasized. We further outline the need for and the state of the art for co-registration of PET and anatomic images for diagnostic and therapeutic purposes. We then review patterns of physiologic uptake of FDG in thoracic structures, including the lung, the heart, the aorta and large arteries, esophagus, thymus, trachea, thoracic muscles, bone marrow, and joints and alterations following radiation therapy to the thorax. A great deal of information is provided with regard to differentiating benign from malignant nodules and in particular, we emphasize the role of dual time point imaging and partial volume correction for accurate assessment of such lesions. Following a brief review of the diagnostic issues related to the assessment of mediastinal adenopathies, the role of FDG-PET imaging in environment-induced lung diseases, including pneumoconiosis, smoking, and asthma are described. A large body of information is provided about the role of this technology in the management of patients with suspected infection and inflammation of the lungs such as acquired immunodeficiency syndrome, fever of unknown origin, sarcoidosis, chronic granulomatous disease and monitoring the disease process and response to therapy. Finally, the value of FDG-PET in differentiating benign from malignant diseases of the pleura including asbestosis-related disorders is described at the conclusion of this comprehensive review.

Animals↗
PubMed2002

18-fluorodeoxyglucose positron emission tomographic imaging in the detection and monitoring of infection and inflammation.

During the past decade, 18-fluorodeoxyglucose (FDG) positron emission tomography (PET) has rapidly evolved from a pure research modality to a clinical necessity. FDG-PET was introduced to determine the state of brain function in physiologic and pathologic states. Its use as a powerful tool to diagnose, stage, and monitor patients with a variety of malignancies has been truly revolutionary. However, FDG is a nonspecific tracer and it has been found to accumulate at sites of infection and inflammation. It is becoming evident that PET imaging will play a major role in the treatement of patients with suspected infection and inflammation. PET has been shown to be particularly valuable in the evaluation of chronic osteomyelitis, infected prostheses, sarcoidosis, fever of unknown origin, and acquired immunodeficiency syndrome. Because of its ability to quantitate the rate of FDG uptake, PET may prove to be a powerful modality for the monitoring of disease activity and response to therapy. Novel PET tracers are being tested for imaging infection and inflammation that may further enhance the role of this technique in the appropriate clinical setting. PET imaging to detect and characterize infection and inflammation may become a major clinical indication in the day-to-day practice of medicine.

Acquired Immunodeficiency Syndrome↗
PubMed2002

Tc-99m sulfur colloid and Tc-99m tagged red blood cell methods are comparable for detecting lower gastrointestinal bleeding in clinical practice.

PURPOSE: The objective of this study was to determine whether the Tc-99m red blood cells (Tc-99m RBC) method has a true advantage over the Tc-99m sulfur colloid (Tc-99m SC) technique in a busy clinical practice for detecting and localizing lower gastrointestinal bleeding sites. METHODS: Three hundred fifty-nine consecutive gastrointestinal bleeding studies performed during the past 4 years were reviewed retrospectively. One hundred ninety-three scans were obtained with Tc-99m SC (scan duration, 30 minutes) and 138 studies were performed after the administration of Tc-99m RBC (scan duration, 1 hour). In addition, 28 examinations with Tc-99m SC were followed immediately by Tc-99m RBC scans for a duration of several hours. The results of the two methods were analyzed and the performance of the two techniques was compared. RESULTS: Among 193 scans performed using the Tc-99m SC method, 47 (24.4%) successfully identified the location of the bleeding site, whereas in 138 scans performed using Tc-99m RBC, 38 (27.5%) were successful for this purpose. In the remaining 28 scans in which the Tc-99m SC scan was followed by the Tc-99m RBC study, only 4 (14.3%) positive bleeding sites were identified after a prolonged imaging period. DISCUSSION: The theoretical advantages of the Tc-99m RBC technique compared with the Tc-99m SC method cannot be substantiated by this study. Our findings suggest that the efficacy of these two methods is nearly equal at a practical level. CONCLUSION: The simpler and cost-effective Tc-99m SC method is as efficient as the Tc-99m RBC method when the scanning time is limited to 1 hour and optimal imaging and interpretation schemes are used.

Adult↗
PubMed2002

Incidental detection of colon cancer by FDG positron emission tomography in patients examined for pulmonary nodules.

PURPOSE: Fluorodeoxyglucose (FDG) positron emission tomographic (PET) imaging has been used extensively to diagnose cancer with high rates of sensitivity and specificity. One of its applications is to distinguish benign from malignant pulmonary nodules. It is common to observe colonic uptake on whole-body FDG-PET images. Because patients with lung cancer also tend to be in the age group with the highest incidence of colon cancer, the authors tried to assess the efficacy of FDG-PET for detecting occult colon cancer in patients referred for the evaluation of lung nodules. METHODS: The records of 500 consecutive patients referred for the evaluation of pulmonary nodules were reviewed retrospectively. Among the patients, 197 had no previous clinical or radiographic evidence of abnormalities in the gastrointestinal tract, and none had been found to have any cancer before undergoing an FDG-PET study. All colon lesions were verified either by histologic analysis or by clinical course. RESULTS: Among the 197 patients analyzed, 59 had diffuse colonic uptake in various segments of the colon. Seventeen of the patients had focal colonic uptake, five of which were proved to be colon cancer. CONCLUSIONS: The routine use of FDG PET to characterize lung lesions significantly increases the probability of detecting unexpected extrathoracic disease. In these patients, the incidental finding of colon cancer had an important effect on their treatment and may prove to be very cost-effective.

Adenocarcinoma↗
PubMedDate not supplied

2-Deoxy-2-[F-18]fluoro-D-glucose-positron emission tomography in characterization of solid renal masses.

UNLABELLED: The present study was aimed to evaluate the ability of 2-deoxy-2-[F-18]fluoro-D -glucose (FDG)-positron emission tomography (PET) in characterization of solid renal masses visualized by computed tomography (CT)/magnetic resonance imaging (MRI) in patients with suspected or known malignancies. METHODS: Twenty-eight solid renal masses (20 unilateral and four bilateral, Size ranges, 1.0-8.4 cm) were evaluated in 24 patients. The results were correlated with histopathology in 15 patients, and clinical follow-up and conventional imaging in all patients. RESULTS: Of the 28 solid renal masses, 10 were primary (nine malignant, one benign) and 18 were metastatic renal tumors. FDG-PET accurately depicted 23 of 27 (85%) malignant renal masses. Of the 10 primary renal tumors, FDG-PET was true positive in eight of nine (89%), true negative in one and false negative in one. The maximum and average standardized uptake values (SUVs) for FDG positive primary renal malignant tumors were 7.9 +/- 4.9 and 6.0 +/- 3.6, respectively. In addition to the characterization of primary tumors, FDG-PET was valuable in primary staging and altered treatment in 30% of patients (three of 10). Of the 18 metastatic renal masses, FDG-PET was positive in 15 (83%) masses. The maximum and average SUVs of metastatic renal masses were 6.1+/- 3.4 and 4.7+/- 2.8, respectively. There was no significant difference in maximum and average SUVs between primary and metastatic renal masses (p=0.3 and p=0.3). CONCLUSION: Despite the physiological excretion of FDG by the kidneys, FDG-PET can be employed effectively in characterization of solid renal masses in patients with suspected or known malignancies. We propose that FDG-PET could be useful as a complimentary modality to conventional imaging in these patients.

Adult↗
PubMedDate not supplied

Standardized uptake values of normal breast tissue with 2-deoxy-2-[F-18]fluoro-D: -glucose positron emission tomography: variations with age, breast density, and menopausal status.

OBJECTIVE: This study was conducted to assess the effect of breast density, age, and menopausal status on the 2-deoxy-2-[F-18]fluoro-D: -glucose (FDG) uptake in normal breast tissue by quantitative standardized uptake values (SUV). METHODS: A total of 96 patients (premenopausal 54; postmenopausal 42) with histologically proven unilateral breast cancer who underwent FDG-positron emission tomography (PET) scans for staging were included in this study. The median age was 52+/-11 years (range 32-79 years). Fifty-nine patients had grade III or IV mammographic density (dense breast), whereas 37 patients had grade I or II breast density (nondense) according to the ACR Lexicon criteria. In the present study, we analyzed maximum and average SUVs for contralateral normal breast. RESULTS: Maximum and average SUVs for normal dense breasts were 1.02+/-0.30 and 0.84+/-0.27, respectively. Similar values for the nondense breasts were 0.66+/-0.24 and 0.53+/-0.23, respectively. Both maximum and average SUVs of dense breasts were significantly higher than those of nondense breasts (p<0.001). There was no significant difference in SUVs of nipple in patients with dense and nondense breasts. There was no significant effect of age and menopausal status on SUVs of normal breast. However, there were trends of negative relationship, i.e., decreasing SUVs with increasing age. CONCLUSION: There was a significant difference in SUVs between the dense and nondense normal breast. However, the maximum SUVs in the dense breasts were well below the threshold of 2.5, a widely used cutoff value for malignancy. Menopausal status and age do not significantly affect the uptake of FDG.

Adult↗
PubMedDate not supplied

18-fluorodeoxyglucose positron emission tomography as a novel imaging tool for the diagnosis of aortoenteric fistula and aortic graft infection--a case report.

The diagnosis of aortic graft infection and aortoenteric fistula can be difficult to establish using conventional radiographic imaging modalities. Positron emission tomography (PET) imaging with 18-fluorodeoxyglucose (FDG) can rapidly provide anatomically clear images and define areas of inflammation with increased glucose metabolism. In this report the authors present a case of aortoenteric fistula diagnosed by FDG-PET. Early diagnosis led to rapid surgical intervention with graft removal and extraanatomic bypass. These encouraging results warrant larger controlled studies to evaluate the utility of FDG-PET in the diagnosis of prosthetic aortic graft infection.

Aged↗