Active inflammatory bowel disease: evaluation with 99mTc (V) DMSA scintigraphy

PURPOSE: To evaluate the use of pentavalent (V) technetium 99m (99mTc) dimercaptosuccinic acid (DMSA) scintigraphy for the assessment of disease activity in patients with inflammatory bowel disease (IBD). MATERIALS AND METHODS: 99mTc (V) DMSA scintigraphy was performed in 76 patients. There were 36 patients with active IBD (11 with ulcerative colitis, 25 with Crohn disease), 28 patients with inactive disease (eight with ulcerative colitis, 20 with Crohn disease), and 12 patients with miscellaneous bowel disease. Sensitivity and specificity of 99mTc (V) DMSA scintigraphy in the diagnosis of IBD were calculated. In the group with active IBD, the disease activity and laboratory indices, as well as the endoscopic and histologic activity, were compared with the scanning activity index. Correlation coefficients between them were calculated with the Spearman rank test. RESULTS: 99mTc (V) DMSA scintigraphy had a 92% (33 of 36) sensitivity and an 86% (24 of 28) specificity in the detection of active IBD. A significant correlation between disease activity indices and scintigraphy score was demonstrated. Endoscopic and histologic activity was significantly correlated (P =.005 and.02, respectively, overall disease activity) with the scanning activity score. Of the group of patients with miscellaneous bowel disease, three with ischemic colitis had negative findings at scintigraphy. CONCLUSION: 99mTc (V) DMSA scintigraphy provides a noninvasive, practical, and accurate assessment of IBD activity.     

The role of Tc-99m (V) DMSA scintigraphy in the evaluation of superscan on bone scintigraphy

PURPOSE: This study evaluated the biodistribution of Tc-99m (V) DMSA in patients with superscans on bone imaging and defined its role in differentiating the underlying cause. METHODS: Nine patients (five with metastatic and four with metabolic bone disease) with classical superscans were entered into the study. All patients had the necessary radiologic and biochemical studies and a final diagnosis was reached accordingly. Tc-99m (V) DMSA scintigraphy was performed 1 week after Tc-99m MDP whole-body bone imaging. RESULTS: In four of five patients with widespread skeletal metastases, Tc-99m (V) DMSA scan showed diffusely increased bone uptake. In the remaining patient, the Tc-99m (V) DMSA scan showed a normal distribution pattern. All patients with metabolic bone disease had increased bone uptake on Tc-99m (V) DMSA scans. CONCLUSION: Tc-99m (V) DMSA shows increased bone uptake in patients having a superscan appearance in metastatic or metabolic bone disease. Tc-99m (V) DMSA imaging may play a role in the evaluation of patients with equivocal bone scan findings for a superscan.     

Megaureter visualization on Tc-99m DMSA scintigraphy

We present a patient with left-sided obstructed megaureter secondary to neuropathic bladder. He was referred for technetium-99m dimercaptosuccinic acid ((99m)Tc-DMSA) renal cortical scintigraphy to evaluate renal cortical function. Images obtained 4 hr after injection showed significant activity in the dilated left ureter. When the ureter is visualized on DMSA scan, obstructive megaureter should be considered in the differential diagnosis.     

Tc-99m pentavalent DMSA scintigraphy in myelofibrosis detection

In a 62-year-old man with medullary carcinoma of the thyroid, a postoperative Tc-99m dimercaptosuccinic acid [(V) DMSA] study was requested. In the Tc-99m (V) DMSA scan. no abnormalities, indicating local recurrence or metastatic disease, were observed. However, there was increased uptake in the spleen and liver and significantly diffusely increased uptake in the bone marrow. The patient also had a history of myelofibrosis and these findings appear to have been the result of this pathology.     

The role of DMSA renal scintigraphy in the first episode of urinary tract infection in childhood

Objective

The role of dimercaptosuccinic acid (DMSA) renal scintigraphy in the first episode of urinary tract infection (UTI) has been the subject of debate for many years. The aim of this study was to evaluate the relationship of voiding cystourethrography (VCUG), renal ultrasonography and DMSA renal scintigraphy and to detect renal parenchymal changes by performing DMSA renal scintigraphy at 6 months after the first episode of UTI.

Methods

A prospective study was conducted in 67 hospitalized children (46 boys, 21 girls). Mean age of the patients was 0.97 ± 1.57 years (0.02–7.26 years). All children received VCUG, renal ultrasonography and DMSA renal scintigraphy. DMSA renal scintigraphy was performed at 1 and 6 months after UTI.

Results

Of 67 children, 17 (25.4 %), 23 (34.3 %) and 20 (29.9 %) had vesicoureteral reflux (VUR), abnormal renal ultrasonography and abnormal DMSA renal scintigraphy, respectively. Unilateral hydronephrosis had a significant correlation with VUR at p value 0.024. In renal units, abnormal renal ultrasonography and hydronephrosis had significant correlations with VUR at p values 0.039 and 0.021, respectively. In patients and renal units, hydronephrosis had no significant correlation with abnormal DMSA renal scintigraphy at 1 month after UTI. However, abnormal renal ultrasonography and VUR had significant correlations with abnormal DMSA renal scintigraphy at p values 0.022 and <0.001 in patients and at p values 0.024 and <0.001 in renal units, respectively. Both in patients and renal units, VUR (Grade I–III) had no significant correlation with abnormal DMSA renal scintigraphy. However, severe VUR (Grade IV–V) had significant correlations with abnormal DMSA renal scintigraphy at p values <0.001 and <0.001, respectively. Seventeen patients underwent DMSA renal scintigraphy at 6 months after UTI. In addition, 15 (88.2 %) developed persistent renal scarring.

Conclusion

Abnormal renal ultrasonography and severe VUR identify renal parenchymal changes. DMSA renal scintigraphy in the first episode of UTI should be carried out in those patients. Abnormal DMSA renal scintigraphy at 1 month after UTI has a tendency to persist.     

Increased bone marrow uptake on Tc-99m DMSA scintigraphy in a patient with renal osteodystrophy

A 16-year-old male patient was evaluated with Tc-99m Diethylenetriamine-pentaacetic acid (DTPA) and Tc-99m 2–3 Dimercaptosuccinic acid (DMSA) scintigraphy for renal failure secondary to renal calculi. The uptake in the renal cortex was significantly decreased both on DMSA and DTPA studies. Uptake calculation on DMSA scintigraphy in the kidneys disclosed values of less than 5 %. The activity in the liver and bone was significantly increased. A bone scan performed with Tc-99m methylene diphosphonate (MDP) revealed increased bone uptake with decreased soft tissue activity. Findings on bone scan were compatible with super scan, most likely due to renal osteodystrophy. This case illustrates the altered biodistribution of Tc-99m DMSA and a shift of the radiopharmaceutical to the bone marrow which is mot likely related to colloid formation due to changes in mineral balance in patients with renal failure.     

99mTc bone scintigraphy superscans: a review

Whole-body bone scintigraphy (bone scan) using a (99m)Tc-labelled pharmaceutical is one of the most commonly performed radionuclide examinations. In the normal patient, both the osseous components of the skeletal system as well as the kidneys and bladder are visualized. A superscan is defined as a bone scan which demonstrates markedly increased skeletal radioisotope uptake relative to soft tissues, in association with absent or faint genito-urinary tract activity. While a superscan is relatively uncommon, its recognition is important, as it is associated with a number of important underlying diseases. The purpose of this review article is to describe the causes and variable features of a superscan and depict patterns which may aid in defining the underlying cause for the scan. In addition, we will discuss other investigations that may help further to identify the underlying disease in such cases.     

The role of Tc-99m (V) DMSA scintigraphy in the diagnosis and follow-up of lung cancer lesions

Objective To define the role of Tc-99m (V) dimercaptosuccinic acid (DMSA) scanning in the detection of lung cancer (LC) and its metastases, and monitoring the response of LC lesions (LCL) to chemo/radiotherapy (TH). Methods Tc-99m (V) DMSA whole-body scans, planar thorax views, and thorax Single-photon emission computed tomography (SPECT) images were obtained both 30 min (early) and 5 h (late) after Tc-99m (V) DMSA administration in 12 small/nonsmall cell LC patients (11 men, 1 woman; mean age 59 years). Five patients also had bone scans. The same scintigraphic protocol was performed in 7 of 12 patients, 3 weeks after first-line TH. TH response was evaluated visually in all LCL and semiquantitatively in primary tumors (PT) of six patients, by comparing the tumor uptake ratios (TUR) of pre-TH and post-TH Tc-99m (V) DMSA SPECT [TUR = mean counts of region of interests (ROI) in PT/mean counts in contralateral ROI]. In seven patients, a 6-month survival was determined. Results Tc-99m (V) DMSA accumulated in 34 LCL (11 PT, 19 bone metastases, 1 suprarenal mass, 1 axillary node, 2 supraclavicular nodes). A total of 11 patients displayed Tc-99m (V) DMSA uptake in LCL and one patient did not show uptake. In six patients, SPECT imaging showed deeply located PT in the lung parenchyma better than planar views. In five patients, both planar and SPECT views revealed peripherally located PT in the lungs. Early scans showed 18 LCL and late scans displayed all the LCL. Nine bone metastases on pre-TH Tc-99m (V) DMSA scans revealed matched areas of increased Tc-99m methylene diphosphonate (MDP) uptake on bone scans; six bone metastases were additionally detected on Tc-99m (V) DMSA scans when compared with bone scans, and four bone metastases on Tc-99m (V) DMSA scans could not be compared with bone scans because bone scan was not performed. In one patient, Tc-99m (V) DMSA scans became positive for bone metastases on post-TH later than the bone scans for some of the bone metastases. Neither planar nor SPECT imaging showed mediastinal lesions defined on thorax CT in nine patients. On TH monitoring, 17 LCL showed diminished Tc-99m (V) DMSA uptake, one disappeared, four were unchanged, three displayed increased uptake, and five new lesions were established. Of the six patients, TUR in PT increased in two (one survived), decreased in one (exitus), was unchanged in two (two exitus) on post-TH scans, and PT totally disappeared in one (survived) patient. Conclusions Tc-99m (V) DMSA scans are useful in detecting LCL, except for those around the blood pool regions, making it a promising modality to monitor TH response. Obtaining a single fifth hour late Tc-99m (V) DMSA scan is appropriate. SPECT should be applied to all patients for the detection of deeply located lesions.     

The usefulness of 99mTc tetrofosmin scintigraphy in patients with breast cancer recurrences

To verify the usefulness of 99mTc tetrofosmin scintigraphy in the follow-up of breast cancer patients, we studied 72 surgically treated breast cancer patients with suspected local recurrences (20 cases) or distant metastases (52 cases) at clinical examination and/or at conventional imaging procedures (CIPs). In all patients, a whole-body scan followed by planar and single photon emission tomography (SPET) images of selected sites were acquired 10 min after the intravenous injection of 740 MBq of 99mTc tetrofosmin, using a rectangular dual-head gamma camera equipped with high-resolution parallel-hole collimators. Loco-regional recurrences were diagnosed in 19 patients and distant metastases in 44 cases, while benign lesions were ascertained in nine cases. 99mTc tetrofosmin SPET showed higher sensitivity, specificity and accuracy per patient than did CIP (96.8% vs 85%, 77.7% vs 55.5% and 94.4% vs 81.1%, respectively) with statistical significance for accuracy (P <0.05). The combined use of SPET and CIP achieved 100% sensitivity and 98.6% accuracy. Planar imaging did not give additional information in respect of either SPET or CIP, showing significantly lower sensitivity and accuracy values (47.6% and 52.8%, respectively). Our data seem to suggest that 99mTc tetrofosmin SPET, but not planar, may be useful in the follow-up for the detection of loco-regional and distant recurrences in patients with breast cancer. The technique can play a complementary role to conventional diagnostic imaging procedures in selected patients.     

99Tcm-奥曲肽显像在淋巴瘤诊断中的应用

目的评价^99Tc^m-奥曲肽显像在淋巴瘤中的临床应用价值。方法11名健康志愿者和30例淋巴瘤患者进行^99Tc^m-奥曲肽显像。所有患者均进行了体格检查，胸部和腹、盆部CT，颈部和腹股沟B超检查，部分完成了腹、盆腔B超检查（11例），^67-Ga-枸橼酸盐全身显像（5例）和骨髓检查（8例）。结果在志愿者中，^99Tc^m-奥曲肽可使脑垂体、鼻咽部、甲状腺、肝、脾、双肾、膀胱、胆囊、消化道等组织器官显影，骨骼和骨髓区内放射性分布明显低下或缺损。在30例患者中，^99Tc^m-奥曲肽显像发现22例阳性，其中2例为淋巴结炎性反应性增生疾病。其诊断患者的灵敏度和特异性分别为83．3％（20／24）和4／6，假阴性率为16．7％（4／24）；诊断病灶的灵敏度为49．3％（72／146）；对膈肌上区和膈肌下区淋巴瘤病灶的诊断灵敏度分别为51．6％（48／93）和45．3％（24／53）。显像发现4个假阳性病灶，对病灶的诊断特异性为99．6％（990／994）。结论^99Tc^m-奥曲肽显像探测淋巴瘤病灶的灵敏度较低；其无法对恶性淋巴瘤和淋巴结炎性反应性增生进行鉴别。     

UK audit of relative renal function measurement using DMSA scintigraphy

A variety of software is used to determine quantitative parameters from radionuclide imaging procedures. Knowledge of the variability of parameter values found in different hospitals is an important aspect of clinical audit of these techniques. This study investigated the variation in relative renal function measurement from static DMSA scintigraphy in the UK. Ten studies representing a range of ages and relative function values were distributed in digital form to 100 hospitals with the assistance of the gamma camera computer suppliers and regional audit coordinators. The studies were analysed at each participating hospital and details of the different techniques and computer systems used were documented. The median value of relative percentage function was assessed for each of the studies. Methods varied in terms of the view used for analysis (54% geometric mean, 46% posterior), the type of background subtraction (single region 32%, separate regions 60%, none 8%) and the definition of the renal regions of interest (73% manual, 27% semi-automatic). Eighty-eight percent of results were within two percentage points of the study median and 98% within five percentage points. There were statistically significant differences observed in the results arising from the view used for the analysis and the background subtraction protocol. The results indicate that relative renal function assessment from static DMSA scintigraphy in the UK is essentially a reliable procedure, although improvements could be made by standardizing the technique used.