Joint scanning in rheumatoid arthritis: a literature review

The role of bone scintigraphy in the diagnosis of rheumatoid arthritis according to the 2010 ACR/EULAR classification criteria

We aimed to investigate the role of bone scintigraphy (BS) in the diagnosis of rheumatoid arthritis (RA) as a supplement to the 2010 American College of Rheumatology (ACR)/European League Against Rheumatism (EULAR) criteria. A total of 156 patients who underwent BS with screening laboratory to confirm RA were enrolled. We divided them into two groups according to the presence of arthritis upon the first physical examination, and evaluated the diagnostic validity of BS as an independent (BS only) or assistant diagnostic tool using the 2010 criteria (BS-assisted). Seventy-five patients had active arthritis (Group I), while the remaining 81 patients did not (Group II). Among them, 56 patients in group I and 5 patients in group II were finally classified as RA. In the group I patients who were eligible for application of the 2010 criteria, the sensitivity of the BS only and BS-assisted diagnosis was not superior to that of the 2010 criteria. However, BS-assisted diagnosis showed high positive prediction values in group I patients with 2010 criteria score < 6 and group II patients. Therefore, BS is still helpful to detect RA even after the introduction of the 2010 criteria, especially among patients who do not satisfy the 2010 criteria as well as those who are ineligible for the 2010 criteria due to dubitable arthritis at clinical presentation.

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.

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.

99m Tc-HMPAO labelled leukocyte scintigraphy in patients with rheumatoid arthritis: a comparison with disease activity

The aim of this study was to test the applicability of 99mTc-hexamethylpropylene amine oxime (99mTc-HMPAO) labelled leukocyte joint scintigraphy in the assessment of disease activity in 21 patients with rheumatoid arthritis, and to compare leukocyte scintigraphy with the Disease Activity Score (DAS), a validated activity index developed by the European League Against Rheumatism (EULAR). Twenty-one patients with rheumatoid arthritis were investigated by using 99mTc-HMPAO labelled leukocyte joint scintigraphy. The clinical and laboratory data were recorded, and the DAS was calculated and compared with the scintigraphic results in each case. A relatively high DAS score (4.71+/-1.07) was found in the majority of patients. The degree of accumulation of 99mTc-HMPAO leukocytes showed no correlation with a patient's age, gender, duration of disease, use of disease modifying anti-rheumatic drugs (DMARDs), visual analogue scale (VAS), Richie index, DAS, or any laboratory parameters. In contrast, a significant correlation was found between the global regional accumulation of the labelled leukocytes of the hands and feet, and the swollen-joint count. It is concluded that radiolabelled leukocyte scintigraphy could become one of the promising methods in the assessment of disease activity in patients with rheumatoid arthritis.

Scintimetric assessment of synovitis activity during treatment with disease modifying antirheumatic drugs

In a double blind trial of 36 patients with rheumatoid arthritis a new scintimetric method was applied to three comparable patient groups before and after eight months' treatment with levamisole, penicillamine, or azathioprine. Technetium-99m pyrophosphate scintigraphy of both hands was performed on a gammacamera with a computer attached, immediately after the administration of the tracer. The uptake ratio of each proximal interphalangeal (PIP) joint and the mid-half of the adjacent proximal phalanx was calculated from the activity counted for one minute. A scintimetric index was expressed as the sum of eight uptake ratios. This index was higher for each of the three patient groups before start of treatment than that for 10 age matched controls. After eight months of treatment the index, the number of PIP joints with clinical signs of synovitis, and the total circumference of the PIP joints decreased in the penicillamine and azathioprine groups. The scintimetric method reliably reflected local synovitis activity and its changes but, like grip strength and PIP circumference, was not a representative measure of the overall activity of the disease.

Value of joint scintigraphy in the prediction of erosiveness in early rheumatoid arthritis

The value of scintigraphy in predicting development of new erosions in small peripheral joints was studied by visual evaluation of scintigrams and by three computerised methods. In 13 patients with newly diagnosed rheumatoid arthritis a total of 387 joints were examined clinically, scintigraphically, and radiographically. The follow up period was 24 months. Four eroded joints in three patients were found at the onset. Of the joints which were to become eroded, 46/47 were scintigraphically active at all the check ups. Erosions were detected earlier in foot joints than in finger joints. New erosions were especially prone to appear in joints with persisting and high scintigraphic activity. On the contrary, inactive joints by repeated scanning never eroded. Scintigraphic and clinical activity and radiographic erosiveness correlated significantly with each other. The sensitivity and specificity of visual scintigraphic assessment and the relative pixel activity method proved to be superior to the region of interest methods and clinical evaluation for prediction of erosiveness.

Quantitation of arthritis by 99mTc-uptake measurements in the mouse knee-joint: correlation with histological joint inflammation scores

A method is described to detect and to quantitate inflammation in knee-joints of mice. Approximately 10 muCi 99mTechnetium pertechnetate (99mTc) is injected subcutaneously in the neck region and the accumulation of the short-lived isotope in the knee-joint is detected by external gamma counting. 99mTc-uptake values correlate well with histological grading of joint inflammation at various intervals after induction of the inflammation. The method can be used to detect changes in activity of unilateral as well as bilateral joint inflammation using either the ratio of 99mTc uptake in the right knee versus that in the left knee or absolute 99mTc-uptake values.

Quantitative sacroiliac scintiscanning: a sensitive and objective method for assessing efficacy of nonsteroidal, anti-inflammatory drugs in patients with sacroiliitis

Serial computer assisted quantitative sacroiliac scintiscanning (SI joint/sacrum ratios) 3 hours after low dosage (5 mCi) 99mTc methylene diphosphonate has been used as an objective index of sacroiliitis in a single blind 14-day cross-over comparison of azapropazone 600 mg b.d. and naproxen 500 mg b.d. in 18 patients with active sacroiliitis. Clinical assessments included visual analogue scales for measurement of pain and early morning stiffness, chest expansion, a modified Schober test, and goniometric measurement of thoracolumbar spinal flexion by means of an inclinometer. Statistically significant decreases in pain (p less than 0.001) and early morning stiffness (p less than 0.001) followed treatment with each NSAID, but there was no significant difference in the fall in these parameters, although 15 out of 18 patients expressed a preference for naproxen. Chest expansion and thoracolumbar flexion were not significantly affected by either drug. Serial quantitative scintigraphy showed a mean fall in joint sacrum ratios following each treatment which was statistically significant (p less than 0.02) only after naproxen. Serial quantitative scintigraphy can be used as an objective method of assessing sacroiliitis and was sufficiently sensitive to reflect the patients' subjective preference in a short-term comparison of 2 NSAID.

Sequential joint scintigraphy in rheumatoid arthritis

In this sequential study joint scintigraphy was compared with clinical and röntgenological evaluation in 19 patients with rheumatoid arthritis. Scintigraphy sometimes preceded clinical and radiological abnormalities and scan results were independent of radiological findings showing no differences when large and small joints were compared. Scan findings in 2 patients with arthralgias only were negative, suggesting that arthritis was unlikely.