Gallium uptake in complicated pancreatitis: a predictor of infection

OBJECTIVE. A retrospective evaluation was performed of the use of gallium imaging in patients with known severe pancreatitis to detect infection in pancreatic and peripancreatic fluid collections. MATERIALS AND METHODS. Gallium-67 single-photon emission computed tomography (SPECT) studies were retrospectively reviewed in patients with complicated pancreatitis. Only patients who had undergone interventional procedures within 10 days of the scanning were included in our analysis. A total of 23 scans from 20 patients were reviewed. SPECT imaging was typically performed 48-72 hr after injection of the gallium. All studies were correlated with conventional CT findings. Findings from subsequent interventions (results of aspiration, Gram stains, or cultures) were used as evidence of infection. RESULTS. Twenty patients underwent either percutaneous or surgical drainage within 10 days of their gallium scanning. One patient underwent gallium scanning on three different occasions and underwent three different interventional procedures after each of the gallium scans, bringing the total number of cases in our study to 23. Of these 23 cases, 18 patients (78%) with gallium scans showing positive findings for infection had infected fluid; five patients (22%) with negative findings for infection on gallium scans had sterile fluid (p < 0.00001). No false-positive scans were found among our study cases, and we found no correlation between the uptake of gallium and the presence or absence of pancreatic necrosis. CONCLUSION. Gallium does not actively accumulate in all patients with severe pancreatitis, and gallium uptake does not correlate with the presence or absence of necrosis. In patients with severe pancreatitis complicated by fluid collections or inflammatory masses, gallium SPECT is a useful predictor of infection and can be used to help guide subsequent intervention. Gallium SPECT allows targeting sites of infected fluid in patients with multiple fluid collections and potentially obviates intervention in patients with sterile fluid collections.     

SPECT gallium-67 scanning in early human immunodeficiency virus (HIV) infection. Failure of scanning abnormalities to correlate with immunologic staging

The use of gallium scanning in the treatment of patients with AIDS has been well described. In this study, 27 HIV-infected patients (Walter Reed Staging Classification I-V) with normal chest roentgenograms were evaluated to determine the occurrence of thoracic gallium abnormalities in early HIV infection. SPECT was used for gallium scanning. Patients received gallium injection on day 1 and bronchoalveolar lavage on day 2, and scanning was performed on day 3. Twenty-eight scans in 27 patients were performed. Mean nodal SPECT activity was compared with corresponding values for lung parenchyma, bronchoalveolar lavage cell counts, and peripheral blood T4 lymphocyte counts. No relationship between nodal and parenchymal activity and cell counts was observed. Although visual scan interpretation was unaffected, gallium activity was significantly increased in the region of bronchoalveolar lavage compared with uptake in other lung regions. It is concluded that SPECT gallium scanning demonstrates significant gallium avidity in recently lavaged lung areas, although no impact on visual scan interpretation was seen. Further, no correlation was seen between the degree of nodal uptake and the immunologic status of these patients with early HIV infection.     

Does gallium uptake in the pulmonary hila predict involvement by non-Hodgkin's lymphoma?

67Ga imaging of non-Hodgkin's lymphoma is useful for evaluating the presence of viable tumour in a residual mass after treatment. However, we have frequently seen gallium uptake in the pulmonary hila without other evidence of lymphoma. To study the significance of this finding, 79 patients with intermediate grade non-Hodgkin's lymphoma were reviewed. Thirty-seven (47%) had abnormal hilar gallium uptake. Twenty-three of these could be fully evaluated, and only five (22%) had hilar lymphoma. A pattern of bilateral, symmetric hilar uptake was seen in 19 patients, but only one had evidence of lymphoma. In 15 cases, this pattern was seen only on single photon emission computed tomography (SPECT). The aetiology of this uptake remains unknown. It is not treatment related, as 12 patients had hilar gallium uptake prior to chemotherapy. Unless confirmed by other methods, hilar gallium uptake should not be attributed to lymphoma, and should not influence patient management.     

SPECT/CT imaging using a spiral CT scanner for anatomical localization: Impact on diagnostic accuracy and reporter confidence in clinical practice

PURPOSE: To evaluate the incremental benefit in routine clinical practice of computed tomography (CT) scans acquired for anatomical localization on an integrated SPECT/CT which incorporates a spiral CT scanner, in comparison with conventional planar and SPECT scanning. METHODS: The first 50 studies acquired on the integrated system were evaluated by two experienced nuclear medicine physicians who were aware of the patient's clinical history. These included bone scans, gallium scans, octreotide scans, sestamibi parathyroid scans and MIBG scans. For each patient study, abnormalities were assessed on planar and SPECT images for location and provisional diagnosis and a quantitative scale was used to assess reporter confidence. The fused SPECT/CT images were then reviewed and the location and provisional diagnosis noted and reporter confidence was assessed using the same quantitative scale. RESULTS: There were 129 abnormalities detected in 50 patient studies. For localization of abnormalities, the inclusion of the CT resulted in a minor change in 16% of cases and a significant change in 11% over planar/SPECT imaging alone. The confidence of localization was improved moderately in 19% and improved significantly in 6%. For diagnosis, SPECT/CT resulted in a minor change in 10% and a significant change in 9% over planar/SPECT imaging. The confidence of diagnosis was improved moderately in 10% and improved significantly in a further 10% of cases. For the final scan interpretation, there would have been no change in 44% patients, a minor change in 30% and a significant change in 26% with the use of SPECT/CT. CONCLUSION: Use of integrated SPECT/CT with a high spatial resolution, spiral CT used for anatomical localization improves accuracy and reporter confidence in clinical practice. As a result, final reports were different in 56% of the cases, including being significantly different in 26% patients compared to reporting with planar/SPECT alone.     

Bilateral adrenocortical uptake of Ga-67 SPECT during septicemia in a heart transplant patient

Gallium-67 scintigraphy is a valuable agent in the management of fever of unknown origin. The use of SPECT increases its sensitivity and may demonstrate unexpected findings. We report on a heart-transplanted 55-year-old man with postsurgical fever of unknown origin. Ga-67 SPECT showed bilateral abnormal adrenal gland uptake that disappeared after intensive antibiotic therapy as assessed by a new Ga-67 scintigraphy obtained 3 months later. Unilateral and bilateral adrenal uptake of gallium has been reported in several clinical settings, ranging from adrenocortical adenomas to malignant disease such as lymphoma or adrenal metastases. Only one similar case, septicemia with transient adrenal uptake of gallium, has been previously reported.     

Pulmonary Kaposi sarcoma in patients with AIDS: scintigraphic diagnosis with sequential thallium and gallium scanning

Pulmonary Kaposi sarcoma associated with acquired immunodeficiency syndrome (AIDS) is difficult to diagnose because the clinical presentations and radiographic findings are nonspecific. The authors report three proved cases of AIDS-associated pulmonary Kaposi sarcoma diagnosed with sequential thallium and gallium scans. These scans demonstrated abnormal increase of pulmonary thallium uptake, whereas the gallium uptake was negative. In the authors' experience and in reports in the radiology literature, infected areas of the chest are generally thallium-negative on the delayed (3-hour) scans but are gallium-avid, whereas lymphomas are both thallium- and gallium-avid. The authors conclude that sequential thallium and gallium scans can be used to help diagnose pulmonary Kaposi sarcoma and distinguish it from other common AIDS-associated chest complications such as lymphoma and infections.     

~（18）F-FDG符合探测正电子显像在恶性淋巴瘤诊治评估中的应用

目的探讨18F-FDG符合探测正电子显像（SPECT/PET）在恶性淋巴瘤诊治中的应用。方法回顾性分析2006年1月~2010年9月在本院经病理确诊为恶性淋巴瘤67例患者共102次18F-FDGSPECT/PET显像结果。霍奇金淋巴瘤患者9例,1例治疗前行SPECT/PET显像,8例为治疗中、后行检查。非霍奇金淋巴瘤患者58例,16例治疗前SPECT/PCT显像,9例治疗前、后均进行SPECT/PET检查,33例治疗后显像。结果 9例霍奇金淋巴瘤患者中治疗前阳性显像1例,化疗中和（或）放疗后SPECT/PET显像共8例,其中5例完全缓解,1例未见明显缓解,1例部分缓解,1例进展。58例非霍奇金淋巴瘤患者中25例治疗前患者中的SPECT/PET显像24例为阳性（96.0%）。42例接受治疗的非霍奇金淋巴瘤患者（包括9例治疗前后均行检查患者）,其中16例SPECT/PET显像为完全缓解（38.09%）,10例部分缓解（23.81%）,9例病灶有进展（21.43%）,7例缓解后又复发（16.67%）。结论 18F-FDGSPECT/PET在淋巴瘤的临床诊断分期与疗效评估中具有重要的临床价值。     

Infection scintigraphy: added value of single-photon emission computed tomography/computed tomography fusion compared with traditional analysis

PURPOSE: Positron emission tomography (PET)/computed tomography (CT) imaging is a powerful dual-modality integrating physiology and anatomy. Analogously, fusing separate single-photon emission computed tomography (SPECT) and CT images can overcome interpretive challenges in characterizing and localizing abnormalities. This study explores the value of SPECT/CT image fusion compared with traditional "side-by-side" SPECT-CT image review for infectious /inflammatory processes. METHODS AND MATERIALS: We identified 17 abnormal infection/inflammation SPECT scans in 16 patients (11 indium 111 WBC and 6 gallium citrate Ga 67) with a contemporary CT scan. The SPECT and CT images were uploaded onto "side-by-side" workstations, one with fusion software. Two nuclear radiologists reviewed "side-by-side" SPECT and CT images and fused SPECT/CT images. They scored 2 parameters (anatomical localization and diagnostic confidence) using a 4-point scale (1 "not helpful" to 4 "very helpful"). Score differences more than 1 indicated "added value" and less than 0, "no added value". RESULTS: Compared with "side-by-side" SPECT-CT, fused SPECT/CT images yielded "added value" for anatomical localization in 65%, diagnostic confidence in 71%, and altered interpretations in 47% of cases. Greater confidence was achieved in 75% of cases with altered interpretations and 55% of unaltered cases. CONCLUSIONS: The SPECT/CT image fusion outperformed "side-by-side" SPECT/CT review for anatomical localization and diagnostic confidence of infectious/inflammatory abnormalities. Therefore, SPECT/CT fusion potentially influences clinical decisions and treatment options.     

Uptake of gallium-67 citrate in clean surgical incisions after colorectal surgery

Non-specific accumulation of gallium-67 citrate (gallium) in uncomplicated surgical incisions is not uncommon. It is important to know the normal pattern of gallium uptake at surgical incision sites in order to properly interpret the gallium scan when investigating possible wound infection in patients who have undergone abdominal surgery. We studied 42 patients without wound infection after colorectal surgery and performed gallium scans within 40 days after surgery. Patients were divided into three groups according to the interval between the operation and the scan. In group A (26 patients) gallium scan was performed within 7 days after surgery, in group B (8 patients) between 8 and 14 days after surgery, and in group C (8 patients) between 15 and 40 days after surgery. Our data showed that in group A, 61.5% had gallium accumulation at the surgical incision site. In group B, 50% had accumulation of gallium at the surgical incision site, while in group C only one patient (12.5%) showed gallium uptake. It is concluded that the incidence of increased gallium uptake at clean surgical incision sites is high after colorectal surgery. Nuclear medicine physicians should bear in mind the high incidence of non-specific gallium uptake at such sites during the interpretation of possible wound infection in patients after colorectal surgery.     

Uptake of gallium-67 citrate in clean surgical incisions after colorectal surgery

Non-specific accumulation of gallium-67 citrate (gallium) in uncomplicated surgical incisions is not uncommon. It is important to know the normal pattern of gallium uptake at surgical incision sites in order to properly interpret the gallium scan when investigating possible wound infection in patients who have undergone abdominal surgery. We studied 42 patients without wound infection after colorectal surgery and performed gallium scans within 40 days after surgery. Patients were divided into three groups according to the interval between the operation and the scan. In group A (26 patients) gallium scan was performed within 7 days after surgery, in group B (8 patients) between 8 and 14 days after surgery, and in group C (8 patients) between 15 and 40 days after surgery. Our data showed that in group A, 61.5% had gallium accumulation at the surgical incision site. In group B, 50% had accumulation of gallium at the surgical incision site, while in group C only one patient (12.5%) showed gallium uptake. It is concluded that the incidence of increased gallium uptake at clean surgical incision sites is high after colorectal surgery. Nuclear medicine physicians should bear in mind the high incidence of non-specific gallium uptake at such sites during the interpretation of possible wound infection in patients after colorectal surgery.     

Primary malignant lymphoma of the central nervous system by Ga-67 and TI-201 brain SPECT.

Two patients with primary lymphoma of the central nervous system underwent both Ga-67 and TI-201 brain SPECT. Ga-67 scans showed remarkable accumulation of radiotracer corresponding to tumors detected by CT and MRI. More avid uptake was noted on the Ga-67 scans than on the TI-201 scans. In one patient, the intense tracer uptake had disappeared in the Ga-67 study performed after irradiation with 50 Gy. We are convinced that Ga-67 SPECT is useful for detecting and following the progress of primary lymphoma of the central nervous system.     

Correlation of gallium-67 SPECT and CT findings in primary gynecologic lymphoma.

Primary gynecologic malignant lymphomas are rare and gallium (Ga)-67 imaging has proven to be useful to differentiate viable lymphoma from fibrotic or necrotic tissue. Computed tomographic (CT) scan is often used in initial localization and staging of the lymphoma. In this study, we retrospectively analyzed the findings of Ga-67 single photon emission computed tomography (SPECT) correlated with those of CT scan for staging initial disease and also differentiation between active lymphoma and post-treatment changes in the follow-up studies.     

SPECT gallium imaging in abdominal lymphoma

A case of non-Hodgkin's lymphoma of the abdomen studied by gallium SPECT imaging is reported. The tomographic slices accurately demonstrated the location of residual disease after chemotherapy in the region of the transverse mesocolon. Previous transmission CT had shown considerable persistent retroperitoneal lymphadenopathy, but was not helpful in determining the presence of viable lymphoma.     

A case of primary malignant lymphoma of the brain with high uptake of 123I-IMP

Summary In general the ¹²³I-IMP SPECT image of a brain tumor is visualized as a defect. Tumor case with high IMP uptake have been rarely reported. We encountered a case of primary malignant lymphoma of the brain with high IMP uptake on both early and late scans corresponding to the CT lesions. Previously reported positive cases seemed to be confined to the early scan. For the present the exact behaviour of IMP is incompletely understood, but the mechanism of high uptake has been accounted for by increased extraction and increased amine receptors at the tumor sites. We need further information to establish whether these SPECT findings were specific for primary malignant lymphoma of the brain.     

Intracranial mass lesions: sequential thallium and gallium scintigraphy in patients with AIDS

PURPOSE: To determine the efficacy of sequential thallium and gallium scintigraphy to differentiate intracranial neoplasms (lymphoma and glioma) from other nonmalignant intracranial mass lesions among patients with acquired immunodeficiency syndrome (AIDS). MATERIALS AND METHODS: The authors reviewed the cases of 40 patients with human immunodeficiency virus (HIV) who underwent thallium and gallium scanning to evaluate intracranial mass lesions from October 1991 through November 1997. There was a definitive final diagnosis of the nature of the mass lesions in 21 of these cases. In these 21 cases, the scintigraphic patterns were reviewed and were compared with the final diagnosis. RESULTS: On the basis of results at thallium and gallium scanning, the patients were divided into three groups. Group A included 13 patients (11 with brain tumors [lymphomas and gliomas] and two with progressive multifocal leukoencephalopathy [PML]) with thallium-positive, gallium-positive scans. Group B included five patients with intracranial infections (tuberculosis, Cryptococcus, bacteria) with thallium-negative, gallium-positive scans. Group C included three patients (one with PML and two with infarcts) with thallium-negative, gallium-negative scans. All patients with lymphomas were in group A. The sensitivity and specificity of the thallium-positive, gallium-positive pattern for intracranial malignancy were 100% and 80%, respectively. CONCLUSION: Sequential thallium and gallium scanning helped differentiate tumors from nonmalignant intracranial mass lesions and may help differentiate infections from PML or infarcts.     

Positron emission tomography changes management,improves prognostic stratification and is superior to gallium scintigraphy in patients with low-grade lymphoma: results of a multicentre prospective study

Purpose  Positron emission tomography (PET) was evaluated in low-grade non-Hodgkin lymphoma (NHL) to determine its impact on staging and management and to compare PET and gallium scans. Methods  PET resulted in management plan changes in 74 patients with untreated low-grade NHL stages I to III. Patient outcomes to 12 months were documented. Results  PET identified additional lesions in 50% of patients, led to a change in stage in 32%, and had a significant impact on management in 34%. Inferior progression-free survival was noted in patients with additional lesions detected by PET (p=0.001) and in the 28% of patients upstaged by PET to stage III or IV (p=0.024). In a subset of 16 patients undergoing both PET and gallium scans, PET was found to be superior. Conclusion  PET has a major role in the management of low-grade NHL in addition to its proven role in aggressive lymphoma.     

Utility of SPECT in gallium scintigraphy

Whole-body gallium planar scintigraphy is a mainstay for the detection of tumors and inflammatory lesions. Recently, gallium SPECT (single photon emission computed tomography) has become more common in the clinical setting. This diagnostic modality is widely employed in our hospital, and lesions are actually detected by SPECT in some cases. Although the contrast of SPECT images is better than that of planar images, spatial resolution is limited by the limited matrix size. Thus, the overall diagnostic utility of SPECT remains to be confirmed. The usefulness of SPECT for the detection of gallium-accumulated lesions was evaluated in a phantom. In this study, we showed that SPECT is able to detect more smaller and lower gallium accumulations than planar imaging. Thus, SPECT imaging is useful in gallium scintigraphy.     

Chronic osteomyelitis: monitoring by 99mTc phosphate and 67Ga citrate imaging

Thirteen patients with chronic osteomyelitis, treated for 6 months with rifampin, had serial 99mTc phosphate and 67Ga scans to determine their value in assessing response to treatment. In patients who responded to treatment, gallium scans were deemed more accurate than 99mTc phosphate bone scans. The gallium scans, although still abnormal at the end of 6 months of antibiotic therapy, showed an improvement trend in all the responders except one in whom fracture recurred. Worsening or lack of improvement on gallium scans predicted active bone infection in five of six "clinical-failure" patients who had documented active bone infection. 67Ga scans eventually became normal in all patients who remained asymptomatic (excluding one with recurrent fracture). 99mTc phosphate scans became normal in only one of five clinical responders. All nonresponders had persistently abnormal scans, although after 6 months of therapy only four of seven showed worsening or no improvement on the scan. Therefore, 67Ga is preferred over 99mTc phosphate bone scans in the assessment of response to therapy in chronic bone infection. Clinical utility of the gallium scan is most significant in patients whose clinical assessment is uncertain, but routine use of this technique does not appear to be warranted. Gallium images are most valuable when obtained over a period of time, so that the trend of improvement versus nonimprovement is evident.     

Technetium-99m DTPA aerosol and gallium scanning in acquired immune deficiency syndrome

In 11 non-smoking AIDS patients suspected of pneumocystis carinii pneumonia (PCP), the results of Tc-99m DTPA aerosol clearances, gallium scans, and arterial blood gases were compared with those of bronchoalveolar lavage (BAL). Nine patients had PCP. All had increased clearances five times higher than the normal (5.6 +/- 2.3% X min-1 vs 1.1 +/- 0.34% X min-1, N = 10, P less than 0.001), suggesting an increased alveolar permeability. Gallium scans were abnormal in six patients but normal or slightly abnormal in the three others. Four of these nine patients had normal chest x-rays. In two of these the gallium scan was abnormal, but in the two others, only the increased Tc-99m DTPA clearances showed evidence of lung disease. Two patients had normal BAL, with normal clearances and gallium scans. Four out of the nine patients with PCP were studied after treatment. Three recovered and had normal clearance and gallium scans. One still had PCP with increased clearance but normal gallium scan. Gallium scanning and Tc-99m DTPA clearance are useful for detecting lung disease in AIDS patients with suspected PCP and for prompting BAL when chest x-rays and PaO2 levels are normal. Due to its high sensitivity, a normal Tc-99m DTPA clearance could avoid BAL.     

Technetium-99m-DTPA aerosol and gallium-67 scanning in pulmonary complications of human immunodeficiency virus infection.

We retrospectively compared the results of 67Ga chest scans and 99mTc-DTPA aerosol clearance measurements with those of fiberoptic bronchoscopy in 88 patients infected with the human immunodeficiency virus. Of 100 investigations, a pulmonary infection was diagnosed in 39, mainly Pneumocystis carinii pneumonia and a noninfectious disorder was found in 42, mainly Kaposi's sarcoma and lymphocytic alveolitis. Gallium scans and DTPA clearance were abnormal respectively in 74% and 92% of infectious complications, and in 12% and 60% of noninfectious disorders. In 10 cases, DTPA clearance was accelerated, while chest x-ray, arterial blood gases and even gallium scanning were normal. A value of DTPA clearance greater than 4.5%.min-1 was both sensitive and specific for the diagnosis of Pneumocystis carinii pneumonia. The gallium scan was always normal in bronchopulmonary Kaposi's sarcoma. We conclude that in symptomatic patients: (1) DTPA clearance measurements are useful for detecting lung disease when chest x-ray and/or PaO2 are normal and (2) a gallium scan is indicated to distinguish progressive Kaposi's sarcoma from a superimposed second process when radiological abnormalities of pulmonary Kaposi's sarcoma are present.