99mTc-MIBI scintigraphy in untreated stage III multiple myeloma: comparison with X-ray skeletal survey and bone scintigraphy.

Technetium-99m 2-methoxyisobutylisonitrile (99mTc-MIBI) is a lipophilic agent that has been proposed as a useful tracer for the detection of disease sites in patients with multiple myeloma (MM). We performed a prospective study to determine the potential of 99mTc-MIBI imaging for the evaluation of the extent of primary disease in patients with advanced stage MM, compared with skeletal survey and bone scintigraphy. Twenty patients with advanced stage MM at initial diagnosis underwent whole-body 99mTc-MIBI imaging, together with contemporaneous skeletal survey and bone scintigraphy. The findings of 99mTc-MIBI imaging were correlated with the results of skeletal survey and bone scan. All 99mTc-MIBI scans were positive for the presence of active MM, whereas skeletal surveys were positive in 18 patients (90%) with osteolytic lesions. Bone scintigraphy demonstrated MM in only 15 patients (75%). In two patients with no detectable lesions on skeletal survey, 99mTc-MIBI imaging revealed uptake in the spine, corresponding to the abnormalities seen on magnetic resonance imaging (MRI). With respect to the localization of bone lesions, 99mTc-MIBI imaging was superior to bone scintigraphy in 15 patients (75%) and had concordant results with bone scintigraphy in four (20%). 99mTc-MIBI imaging is a very sensitive imaging modality for the identification of the extent of disease in patients with advanced MM. It is clearly superior to bone scintigraphy and complements the results of skeletal survey by finding additional disease sites. Hence, in active MM patients, 99mTc-MIBI imaging has the potential to detect bone marrow disease that cannot be detected by skeletal survey and bone scintigraphy.

Quantitation of defecation function using radionuclide artificial stool in children with chronic constipation.

We aimed to investigate the value of scintigraphically determined evacuation fraction (EVF) as an objective follow-up criterion in medically treated children with chronic constipation, and to evaluate the relation between patients' symptoms and rectal emptying rate. Thirty children (m: 22, f: 8, mean age: 8.9 +/- 0.9 year) suffering from chronic constipation were assessed by scintigraphic evacuation study. All patients underwent anal manometric and scintigraphic examinations before their therapy was started. During 3 months, they received conventional laxative treatment for constipation, and scintigraphic studies were repeated in 20 of 30 patients. Scintigraphic examinations consisted of instillation of artificial stool into the rectum up to the volume impending rectal evacuation, and acquisition of pre- and post-evacuation images. EVF values were then calculated from the images using a fixed region of interest. All of the patients had high resting anal canal pressure (75 +/- 12 mmHg) and had positive rectoanal inhibitory reflex. In 14/20 patients (70%) who benefited from therapy, mean EVF changed from 43.6% to 62.2% (p < 0.001), while decreasing in 6120 who did not benefit. The volume arousing rectal evacuation was significantly lower at the second scintigraphic study (261 +/- 98 ml) than the first study (354 +/- 138 ml) (p < 0.05). As a conclusion: 1) EVF was low in chronically constipated children, 2) it was improved after conventional laxative treatment and, 3) radionuclide EVF determination may be a useful method for follow-up.

Tc-99m HMPAO brain SPECT compared to CT and EEG after seizures in childhood.

Twenty-one children with various seizure disorders were studied using Tc-99m HMPAO brain SPECT, cranial CT, and electroencephalography (EEG). The rates of pathologic findings on SPECT, CT, and EEG were 67%, 38%, and 52%, respectively. SPECT showed congruent, or more extensive, lesions in all eight patient with CT lesions. Six of the 13 children who had normal CT results, had abnormal SPECT study results. In this postictal series, 4 of the 14 abnormalities detected in the first SPECT study that was applied within 24 hours of a seizure, were in the form of hyperperfused areas. Eight of the 14 abnormal first SPECT studies had become normal by the second SPECT. We conclude that, with respect to the depiction of some kind of abnormality, HMPAO brain SPECT is superior to CT and EEG, and considerable changes in brain perfusion are likely to occur over a period of a few weeks.

Scintigraphic detection of splenosis: superiority of tomographic selective spleen scintigraphy.

We used scintigraphy with sulphur colloid and heat-damaged red cells to detect splenosis after splenectomy in 19 patients 7 to 69 months after injury. We compared planar and tomographic selective spleen scintigraphy using heat-damaged red cells with subtracted planar colloid scintigraphy, and showed that the most sensitive method was tomographic selective splenic scintigraphy. The incidence of splenosis was 58% with this method, the other techniques detecting abnormalities in 21% and 26% of the patients.

Detection efficiency of different bone SPECT processing protocols for the diagnosis of "spina bifida".

Bone SPECT is a very important diagnostic tool for the detection of metabolically active lesions, with good anatomical resolution. It is highly technique-dependent however, and the reports about the role of bone SPECT in diagnosing hypoactive lesions are very limited. In order to determine its diagnostic value, we investigated 18 pediatric spina bifida cases with bone SPECT using different processing and displaying methods. The results were evaluated on a 1 to 5 point scale. Although it was not a very effective procedure for small hypoactive bony lesions, we concluded that the processing method using a Butterworth filter, a cut-off frequency 0.50 cycle/cm and a logarithmic gray scale displaying detects bone lesion more efficiently than the Hanning filter with a linear gray scale. The difference between the values produced using the two methods was significant (p < 0.005).