Comparison of Tc-99m HIG and three-phase Tc-99m MDP bone scintigraphy for evaluating the efficacy of Yttrium-90 silicate radionuclide synovectomy

PURPOSE: The aim of this study was to compare Tc-99m human immunoglobulin (HIG) and three-phase Tc-99m MDP bone scintigraphy for the assessment of the efficacy of Y-90 silicate therapy in rheumatoid knee synovitis. MATERIALS AND METHODS: Fifteen patients with rheumatoid arthritis and chronic persistent synovitis in 23 knee joints had radionuclide synovectomy with Y-90 silicate. The patients underwent imaging before and 3, 6, 9, and 12 months after therapy using clinical evaluation, Tc-99m HIG scintigraphy, and three-phase Tc-99m MDP bone scintigraphy. RESULTS: In the 13 of 23 knee joints that showed successful clinical results with Y-90 therapy, the Tc-99m HIG index values obtained 3 months after radionuclide synovectomy were significantly lower than the pretreatment index values (P < 0.001). In the same 13 joints, the Tc-99m MDP index values (in the blood-pool and delayed phases) before and 3 months after therapy were statistically similar. Six months after injection, these values were significantly lower in both the blood-pool (P < 0.001) and late (P < 0.05) phases in all 13 joints. In the other 10 of 23 knee joints that did not respond to treatment, the Tc-99m MDP and Tc-99m HIG index values were statistically similar before and after Y-90 therapy. CONCLUSIONS: Based on these findings, Tc-99m HIG scintigraphy appears to be a valuable method that complements clinical assessment of the efficacy of Y-90 silicate therapy in rheumatoid knee synovitis, starting in the early post-treatment period. However, three-phase Tc-99m MDP bone scintigraphy may be valuable in the late postsynovectomy period.     

Comparison of Tc-99m methylene diphosphonate, Tc-99m human immune globulin, and Tc-99m-labeled white blood cell scintigraphy in the diabetic foot.

PURPOSE: The aims of this prospective study were to evaluate the contribution of Tc-99m methylene diphosphonate (MDP), Tc-99m human immune globulin (HIG), and Tc-99m white blood cell (WBC) to the diagnosis of osteomyelitis in the diabetic foot and to evaluate the surgical or medical therapy with Tc-99m HIG and Tc-99m WBC scans. METHODS: Twenty patients (15 men, 5 women) with suspected pedal osteomyelitis were included in the study. All patients had type II diabetics. Three- and four-phase bone scintigraphy (3P-MDP, 4P-MDP), early (e) and late (l) HIG, and WBC scans were completed within 1 week in all patients. The lesion-to-background ratios were calculated for early and late images of the feet for all scans and named as the indices. Eight weeks after the end of medical or surgical therapy, Tc-99m HIG and Tc-99m WBC scans were repeated in 10 patients. The difference in indices between 3P-MDP and 4P-MDP for osteomyelitis and indices for osteomyelitis, cellulitis, and inflammation in Tc-99m HIG and Tc-99m WBC in early and late scans were tested for significance. RESULTS: In 20 patients, 53 lesions were investigated. Among these 53 lesions were 25 sites of proved osteomyelitis, 6 sites of cellulitis, and 22 sites of inflammation confirmed by radiography, microbiologic culture, and clinical evaluation. 4P-MDP was more specific than 3P-MDP for detecting osteomyelitis (50% and 67%, respectively). There was also a significant difference between the mean indices of 3P-MDP and 4P-MDP (P < 0.000). The index values were increased in 4P-MDP scans. There was no significant difference between the indices of early and late Tc-99m HIG scans for inflammation, cellulitis, and osteomyelitis. Early and late Tc-99m WBC scans did not show a significant difference in differentiating osteomyelitis. However, Tc-99m WBC scans could differentiate aseptic inflammation from infection (P < 0.031) in early and late scans. There was a significant difference of index values between pre- and post-treatment Tc-99m HIG and Tc-99m WBC scans. The best combination of scans for detecting osteomyelitis was 4P-MDP with WBC scans, with an accuracy rate of 92%. CONCLUSIONS: These results show that four-phase bone scintigraphy with early Tc-99m WBC scanning is preferred for detecting osteomyelitis of the diabetic foot. To evaluate the response to therapy, Tc-99m WBC scans are the preferred method, but if this is not available, Tc-99m HIG scanning can be used.     

The role of Tc-99m polyclonal human immunoglobulin G scintigraphy in Graves' ophthalmopathy

OBJECTIVE: The aim of this study was to clarify whether Tc-99m HIG (Polyclonal Human Immunoglobulin G) can image and determine the severity of orbital involvement in patients with Graves' ophthalmopathy. MATERIALS AND METHODS: Twenty-six patients between 19 and 56 years old with Graves' ophthalmopathy were examined. All patients received approximately 370 MBq Tc-99m HIG by i.v. injection. Planar and SPECT examination were performed 4 hours after the injection. Visual and semiquantitative evaluations were performed for both orbits by two independent observers, RESULTS: Clinically active ophthalmopathy patients had noticeably increased orbital accumulation of Tc-99m HIG. In patients with inactive disease, and 14 of 19 had no uptake, whereas 5 patients had orbital radioactivity accumulation. The duration of Graves' ophthalmopathy did not correlate with the presence of active ophthalmopathy and Tc-99m HIG grade. There was no correlation between clinical classification and clinical activity (r = 278). There was a good correlation between clinical activity and the radioactivity grade with r = 0.666 (p = 0.01). The clinical classification closely correlated with Tc-99m HIG grade (r = 0.423, p = 0.05). CONCLUSION: Tc-99m HIG scan can clearly identified clinically active patients, and subclinicial inflammation can be shown by this scintigraphic evaluation. The current preliminary results suggested that Tc-99m HIG SPECT might be useful for the assessment of disease activity in Graves' ophthalmopathy.     

Tc-99m dextran and Tc-99m HIG findings in patients with ulcerative colitis.

PURPOSE: Various radionuclide methods have been studied for the evaluation of the disease activity and extent of ulcerative colitis and other protein-losing enteropathies. Recently, Tc-99m dextran and Tc-99m human immunoglobulin (HIG) have been used to detect inflammation and protein loss into the intestine, but only a few studies have been reported with these agents. MATERIALS AND METHODS: In this study, Tc-99m dextran and Tc-99m HIG were used to evaluate disease activity and extent in patients with ulcerative colitis. These agents were used in 12 patients with active disease and in five patients in remission, and five healthy control participants also were included. RESULTS: Large bowel activity was detected in 11 of the 12 patients with active ulcerative colitis using Tc-99m dextran and in 10 patients using Tc-99m HIG. Fifty-eight bowel segments were found to be active with endoscopy, 39 with Tc-99m dextran, and 31 with Tc-99m HIG. No intestinal activity was detected in the control participants. Grade 1 activity localization in the large bowel was detected in three patients with ulcerative colitis in remission using Tc-99m dextran and in one patient using Tc-99m HIG. CONCLUSION: Tc-99m dextran is more sensitive for detecting disease activity and extent than is Tc-99m HIG.     

Protein-losing enteropathy detected on Tc-99m HSA and Tc-99m MDP scintigraphy

The authors describe a patient with protein-losing enteropathy in whom abnormal intestinal accumulation of tracer occurred during Tc-99m human serum albumin scintigraphy. Abnormal leakage of the radiotracer was observed in the left upper abdomen and was confirmed by Tc-99m MDP scintigraphy. Both Tc-99m HSA scintigraphy and Tc-99m MDP scintigraphy are useful in the detection of protein-losing enteropathy.     

Utility of Tc-99m human polyclonal immunoglobulin G scintigraphy for assessing the efficacy of yttrium-90 silicate therapy in rheumatoid knee synovitis

PURPOSE: The aim of this study was to determine the utility of Tc-99m human polyclonal immunoglobulin G (HIG) scintigraphy for evaluating the efficacy of yttrium-90 (Y-90) silicate therapy in rheumatoid knee synovitis. MATERIALS AND METHODS: Fifteen patients (13 women, 2 men; mean age, 53.5 +/- 8.4 years) with rheumatoid arthritis had radionuclide synovectomy using 185 MBq (5 mCi) Y-90 silicate to evaluate 24 knee joints with chronic persistent synovitis. Radiologic and clinical evaluations and Tc-99m HIG scans were performed in each patient before radionuclide synovectomy. Each patient was reassessed 3, 6, 9, and 12 months after therapy using clinical examination and Tc-99m HIG scintigraphy. RESULTS: In 14 of 24 knee joints (4 Larsen stage I, 10 Larsen stage II) that had excellent or good clinical responses to Y-90 silicate therapy, the Tc-99m HIG index values 3 months after treatment were significantly lower than the pretreatment index values (P < 0.001). In 13 of these 14 joints, these low index values and clinical results remained constant throughout the 1 year of follow-up. One patient (1 of the 14 knee joints) experienced severe pain and swelling as a result of recurrent arthritis at 9 months, and the Tc-99m HIG index value increased at 9 months and remained high 12 months after therapy. In 10 of 24 knee joints (4 Larsen stage II, 6 Larsen stage III) that had a fair or poor clinical response, Tc-99m HIG index values were statistically similar before and after radionuclide therapy. CONCLUSIONS: Quantitative Tc-99m HIG scintigraphy is a valuable method for assessing the efficacy of Y-90 silicate therapy in rheumatoid knee synovitis.     

Tc-99m polyclonal human immunoglobulin G imaging in Graves' ophthalmopathy

PURPOSE: The authors evaluated the utility of Tc-99m-labeled human immunglobulin G (HIG) in determining the severity of orbital inflammation and the relation of orbital Tc-99m HIG uptake and clinical parameters in patients with Graves' ophthalmopathy. MATERIALS AND METHODS: Images were obtained in 23 patients (13 women, 10 men; mean age, 51+/-10 years) with Graves' ophthalmopathy. Planar orbital images were obtained and SPECT was performed using a triple-detector gamma camera 4 hours after 370 MBq (10 mCi) Tc-99m HIG injection. Tc-99m HIG uptake was classified using transaxial and coronal slices as 1, mild; 2, moderate; and 3, severe. The clinical severity of orbital disease was categorized, according to the criteria described by Feldon and Unsold, as class I, mild involvement; class II, moderate; and class III, severe. Disease was considered to be clinically inactive if symptoms and signs were stable or improved in the last two examinations performed at least 6 months apart. RESULTS: Sixteen patients were clinically inactive, and seven patients were active. The mean Tc-99m HIG classes were 1.5+/-0.5 and 2.6+/-0.5, respectively (P = 0.02). There was not a good correlation between the clinical classification and Tc-99m HIG classification, whereas the presence of active disease showed a good correlation with Tc-99m HIG classification (r = 0.703; P = 0.0002). CONCLUSIONS: Tc-99m HIG imaging showed possible ongoing subclinical inflammation in the orbits of the patients with Graves' ophthalmopathy regardless of the clinical classification. Tc-99m HIG SPECT seems a promising procedure for evaluating the presence of active orbital inflammation.     

Malignant pleural effusion and Tc-99m MDP accumulation

Two case reports of malignant pleural effusion from breast carcinoma, with scans showing a striking accumulation of Tc-99m MDP, are presented. The Tc-99m MDP was in the pleural fluid and not in the pleura as demonstrated by shift with gravity. Possible mechanisms of malignant effusion accumulation of Tc-99m MDP are suggested. The scant literature on the subject is reviewed.     

Tc-99m methylene diphosphonate versus Tc-99m pyrophosphate: biologic and clinical comparison.

The biologic and imaging characteristics of Tc-99m MDP and Tc-99m PPi were compared in animals and patients using freeze-dried bone-imaging kits. Biodistribution data in rabbits showed Tc-99m MDP had slightly higher bone uptake, significantly lower blood levels, and faster urinary excretion compared with Tc-99m PPi. Duplicate studies performed on ten patients showed the following: (a) blood clearance of Tc-99m MDP was more prompt and complete, resulting in significantly lower blood levels at 4 hr; (b) urinary excretion was greater with Tc-99m MDP than with Tc-99m PPi; and (c) Tc-99m PPi showed significant red-cell labeling, whereas Tc-99m MDP did not. Image quality was generally better with Tc-99m MDP than with Tc-99 m PPi, although there was no obvious difference in diagnostic sensitivity between the two agents.     

Comparison of Tc-99m pyrophosphate and Tc-99m methylene diphosphonate in acute myocardial infarction: concise communication.

This study compared Tc-99m pyrophosphate (PPi) and Tc-99m methylene diphosphonate (MDP) for myocardial infarct imaging in 24 patients with diagnosed acute myocardial infarction. The radiopharmaceuticals were administered randomly and interpreted without knowledge of the sequence used. Twenty-three patients (96%) had positive Tc-99m PPi scintigrams, but only 17 (71%) had a positive Tc-99m MDP study (P less than 0.05). In addition, a comparison of the relative intensity with each agent revealed greater intensity with Tc-99m in 21 cases, equal intensity in two cases, and less intensity in only one case (p less than 0.001). These findings support the superiority of Tc-99m PPi as the agent of choice for myocardial scintigraphy in acute infarction.     

Comparison of Tc-99m HIG and Ga-67 citrate in the evaluation of bacterial abscess in a rat model

Tc-99m labeled polyclonal human immunoglobulin (HIG) has been shown to be able to localize an inflammatory site. There are several possible explanations for HIG accumulation at focal infection sites such as increased vascular permeability, binding of the Fc part of Ig to Fc receptors of leucocytes and binding directly to bacteria. In this study, we compared Tc-99m HIG and Ga-67 citrate scintigraphy in localizing acute bacterial abscesses induced byE. coli andS. aureus. Serial scintigrams were performed at 1, 4, 24 hr after injection. Tc-99m HIG showed greater accumulation at all times with both infectious agents than Ga-67 citrate (p < 0.05). While Tc-99m HIG showed greater accumulation inS. aureus thanE. coli (p < 0.05), there was no statistically significant difference betweenE. coli andS. aureus (p > 0.05) by Ga-67 citrate. Our study suggests that Tc-99m HIG is a superior agent to Ga-67 and bacterial affinity can be a factor responsible for HIG accumulation at focal sites of inflammation.     

A quantitative evaluation of rheumatoid arthritic activity with Tc-99m HEDP.

In an attempt to develop a quantitative method of evaluating rheumatoid arthritic activity, Tc-99m HEDP joint uptake values and joint-to-bone ratios were studied in ten adult rheumatoid arthritic patients and 17 nonarthritic patients. A joint-to-bone activity ratio of 1.8 at the fourth hour after injection (RA Index) discriminated clinically active rheumatoid arthritic joints from control joints with 95% accuracy. Serial studies on five patients during drug trial demonstrated a positive correlation between RA Index and the clinical manifestations of rheumatoid arthritic activity. The RA Index may be a useful quantitative parameter for evaluation of rheumatoid arthritic activity following therapy.     

Tc-99m hydroxymethylene diphosphonate and Tc-99m methylene diphosphonate: biological and clinical comparison: concise communication

The biologic and imaging characteristics of Tc-99m HMDP and Tc-99m MDP were compared in ten patients. Tc-99m HMDP blood levels were marginally lower at 4 hr. There were no significant differences in 4-hr urinary clearance, normal bone-to-background ratio, or ratio of lesion to normal bone. Relative image quality comparison showed a slight preference for Tc-99m HMDP. Biologically Tc-99m HMDP compares favorably with Tc-99m MDP. Under the conditions of this study, Tc-99m HMDP image quality is at least comparable to that of Tc-99m MDP.     

Tc-99m(V) DMSA imaging. A new approach to studying metastases from breast carcinoma.

Combined Tc-99m MDP skeletal imaging and Tc-99m(V) DMSA whole body scans to detect metastases were performed during the follow-up of 30 patients who underwent surgery for breast carcinoma. Eight patients had normal Tc-99m MDP and Tc-99m(V) DMSA scans and were declared free of metastatic disease, further confirmed by no change in symptomatology over a 1-year follow-up period. Twenty-two patients had positive Tc-99m MDP scans with varied skeletal involvement. Tc-99m(V) DMSA scans showed matched areas of increased radiotracer concentration in bony metastases in 20 of these patients. Tc-99m(V) DMSA concentration was not seen in traumatic vertebral collapse or in coexistent osteoarthritic disease in vertebral metastatic involvement. Interestingly, Tc-99m(V) DMSA showed increased concentration in brain and liver metastases. Pentavalent Tc-99m(V) DMSA appears useful for detecting skeletal and soft-tissue metastases in breast carcinoma, and can improve the specificity of Tc-99m MDP bone scans in screening for bone metastases.     

The role of Tc-99m MDP and Ga-67 citrate in predicting the cure of osteomyelitis

Twenty rabbits with chronic osteomyelitis of the tibia were treated for eight weeks and then scanned with Tc-99m MDP and Ga-67 citrate. All were sacrificed and bacteriologic cultures of the tibia were obtained. All rabbits had positive Tc-99m MDP scans at the end of treatment despite thirteen cures of osteomyelitis. Eight had negative gallium scans and negative cultures. Five of the twelve positive gallium scans had negative cultures, while seven had positive cultures. Tc-99m MDP alone is not sensitive enough to be useful in predicting the cure of osteomyelitis, and combining Tc-99m MDP and Ga-67 citrate scintigrams offers no additional information over the Ga-67 citrate scintigram alone in follow-up of osteomyelitis.     

The comparison of dual phase Tc-99m MIBI and Tc-99m MDP scintimammography in the evaluation of breast masses: Preliminary report

The aim of this prospective study was to determine the diagnostic value of Tc-99m MDP scintimammography (SMG) for the detection of breast cancer in patients with breast masses and to compare the results with Tc-99m MIBI scintimammography. Twenty patients, categorized as suspicious, positive or benign for breast cancer according to the mammographic findings were included in the study. Dual phase Tc-99m MIBI and Tc-99m MDP SMG were performed in the prone lateral position within 5 days of each other. Although early and late Tc-99m MIBI SMG showed equal (90.4%) sensitivity, the specificity of late Tc-99m MIBI (87.5%) was found superior to early (62.5%) imaging. The overall sensitivity and specificity of early Tc-99m MDP SMG were 71.4% and 62.5%, respectively. Although late Tc-99m MDP imaging showed 100% specificity, its sensitivity was only 23.8%. In the patients with palpable masses, both early Tc-99m MDP and Tc-99m MIBI showed equal sensitivity (100%), but the sensitivity of early Tc-99m MIBI (37.5%) was found slightly higher than Tc-99m MDP (25.0%) for nonpalpable breast lesions. The sensitivity of Tc-99m MIBI and Tc-99m MDP SMG in detecting metastatic axillary involvement was 66.6% and 50%, respectively. High sensitivity and specificity together with its low cost, easy availability and the possibility of detecting bone metastases seems to make Tc-99m MDP a contributive agent in the evaluation of breast lesions as an alternative to Tc-99m MIBI.     

Increased liver and spleen accumulation of Tc-99m methylene diphosphonate associated with intravenous injection of MRI contrast gadolinium-diethylenetriaminepentaacetic acid

Several conditions that can cause diffuse hepatic or splenic uptake of Tc-99m methylene diphosphonate (Tc-99m MDP) have been previously reported. Nevertheless, diffuse abnormal liver and spleen uptake of Tc-99m MDP associated with intravenous injection of magnetic resonance imaging contrast gadolinium-diethylenetriaminepentaacetic acid is not previously known. In our series, we reported diffuse increased Tc-99m MDP activity in the liver and spleen in bone scans in patients who received Tc-99m MDP injection shortly after contrast-enhanced magnetic resonance imaging.     

Detection of alveolar epithelial injury by Tc-99m DTPA radioaerosol inhalation lung scan in rheumatoid arthritis patients

Rheumatoid arthritis (RA) is a systemic autoimmune disorder primarily involving the joints. Lung alterations in RA may be primary or secondary to pharmacological treatments and may involve the alveoli, interstitium, airways and/or pleura. Technetium-99m diethylenetriaminepentaacetic acid (Tc-99m DTPA) aerosol inhalation scintigraphy is a sensitive and noninvasive test commonly employed to assess pulmonary epithelial membrane permeability. The purpose of the this study was a) to investigate the changes of pulmonary alveolar epithelial permeability in patients with RA, b) to determine the relationship between the clearance rate of Tc-99m DTPA and pulmonary function test (PFT) results, and c) to determine the relationship between the clearance rete of Tc-99m DTPA and clinical parameters of disease. Twenty-five patients with RA but without lung alterations were included in the study. The patients were 22 females, and 3 males; mean age 53.6 +/- 8.7 years. Technetium-99m DTPA aerosol inhalation scintigraphy was performed on the study and healthy control groups. Clearance half times (T1/2) were calculated by placing a mono-exponential fit on the curves. Penetration index (PI) was calculated on the first-minute image. There were no significant differences in the mean T1/2 or mean PI values between the RA patients and control subjects. No correlation was found between the mean T1/2 values of Tc-99m DTPA clearance and activity of RA, clinical values, or the spirometric measurements except FEV1/FVC and functional status in RA patients (p = 0.02, p = 0.01, respectively). However, a weak correlation was found between duration of disease and T1/2 values of Tc-99m DTPA clearance (p = 0.006). PI values tended to correlate with FEF25-75, although, this was not statistically significant (p = 0.057). This study shows that no changes occur in alveolar-capillary permeability in RA patients without lung alterations.     

Tc-99m ciprofloxacin scans for detection of tubercular bone infection

Tc-99m MDP and Tc-99m ciprofloxacin scans were performed in 14 patients with suspected tubercular bone disease and in 2 cases of nontubercular bone infection. In 5 patients the findings were true negative. There were no false positives and 1 was false negative. The sensitivity, specificity, and positive predictive value were found to be 93, 71, and 87.5%, respectively, for detection of bone tubercular lesions. However, the test does not distinguish TB osteomyelitis from other types of osteomyelitis. Delayed 24 hour scans were found useful to differentiate between inflammatory and infective lesions. The aim of this study was to evaluate the usefulness of the Tc-99m ciprofloxacin scan as a means to detect tubercular bone disease.     

Tc-99m MDP, thallium-201 chloride and Tc-99m MAG3 renal uptake in subacute and chronic radiation nephritis compared

The authors present a comparison of the findings for thallium-201 (Tl-201), Tc-99m MAG3 and Tc-99m MDP in subacute and chronic radiation nephritis in a 9-yr-old boy who was treated by radiation therapy for alveolar rhabdomyosarcoma of the left chest wall by a radiation port that partially included the left kidney. Tl-201 imaging three and six months later showed a cortical defect in the left kidney due to radiation nephritis. Tc-99m MDP scan showed increased uptake on both occasions, but more marked in the subacute period than in the chronic period. Tc-99m MAG3 showed decreased concentration and increased cortical retention three months later. Six months after the radiation therapy, a cortical defect corresponding to the cortical area that showed increased parenchymal retention was more prominent in the Tc-99m MAG3 scan. In the present case, Tc-99m MDP, Tl-201 and Tc-99m MAG3 findings may provide useful information for understanding pathophysiological damage in the kidney after radiation.