Whole-body MRI and PET/CT in multiple myeloma patients during staging and after treatment: personal experience in a longitudinal study.

PURPOSE: Diagnostic imaging plays a pivotal role in staging and prognostic assessment of multiple myeloma (MM) as well as planning and monitoring treatment. The aim of our study was to estimate the diagnostic accuracy of wholebody magnetic resonance imaging (WB-MRI) and positron emission tomography/computed tomography (PET/CT) in MM patients studied before and after treatment. MATERIALS AND METHODS: We considered 22 consecutive patients (10 males, 12 females; age range, 48-83 years) with newly diagnosed MM (NDMM group), and the same 22 patients underwent at least one re-assessment after treatment (previously treated MM, PTMM group). WBMRI and PET/CT were performed within days from each other in both the NDMM (22 studies) and PTMM (29 studies) group. The imaging findings were compared to the results of bone marrow aspiration. RESULTS: PET/CT was positive in 18/22 NDMM patients, whereas WB-MRI correctly identified 100% of patients. Of 20 responder patients in the PTMM group, 16 were negative at PET/CT and 12/20 at MRI. By contrast, of the nine nonresponder patients, MRI correctly detected active disease in all cases, and PET only in seven. CONCLUSIONS: WB-MRI proved superior to PET/CT in detecting MM, especially in diffuse disease. PET/CT appears to be more sensitive in the assessment of MM after treatment.

[Cardiac sympathetic innervation imaging with myocardial MIBG scintigraphy]. / Studio dell'innervazione cardiaca mediante scintigrafia miocardica con MIBG.

Metaiodobenzylguanidine (MIBG) was developed initially as a tracer for oncological imaging; when labeled with 123 I or 131 I, it may detect APUDomas, such as pheochromocytomas and paragangliomas. In the last years, MIBG has found an important role also in neurology and cardiology, as cardiac innervation tracer. Actually, MIBG cardiac imaging is a universally accepted method to estimate cardiac sympathetic innervations. This review covers the role of MIBG cardiac imaging in Parkinson disease and parkinsonisms, from the pathophysiological premises for cardiac denervation to new emerging data.

Combined use of DAT-SPECT and cardiac MIBG scintigraphy in mixed tremors.

The cooccurrence of rest and postural tremor (mixed tremor) as the predominant clinical manifestation in patients who do not fulfill diagnostic established criteria for essential tremor (ET) or Parkinson's disease (PD) poses a clinical diagnostic challenge. Twenty-two patients with mixed tremor and additional mild extrapyramidal features, such as bradykinesia and rigidity, 20 patients with probable PD, 10 patients with probable ET, and 18 controls were investigated through the combined use of dopamine transporter (123)I-FP-CIT-single-photon emission tomography (DAT-SPECT) and cardiac (123)metaiodobenzylguanidine (MIGB) scintigraphy. Six of the 22 mixed-tremor patients had normal DAT-SPECT, a condition usually found in patients with ET, whereas 16 patients showed damage to the nigrostriatal system. Cardiac MIBG allowed further differentiation between these 16 patients because eight of them had decreased tracer uptakes (heart/mediastinum [H/M] ratio in delayed image, H/M ratio delayed: 1.16 +/- 0.11, P < 0.001 vs controls), indicating a PD, whereas the remaining eight had normal cardiac tracer uptakes, a finding suggestive of a parkinsonian syndrome (H/M ratio delayed: 1.90 +/- 0.13). Both DAT-SPECT and cardiac MIBG scintigraphies were abnormal in the 20 patients with probable PD, whereas these were normal in both the patients with probable ET as well as in the controls. Our study suggests that the combined use of both DAT-SPECT and MIBG scintigraphy in mixed tremors with additional extrapyramidal features can help distinguish patients with ET from those with PD and parkinsonism.

124 Iodine: a longer-life positron emitter isotope-new opportunities in molecular imaging.

(124)Iodine ((124)I) with its 4.2 d half-life is particularly attractive for in vivo detection and quantification of longer-term biological and physiological processes; the long half-life of (124)I is especially suited for prolonged time in vivo studies of high molecular weight compounds uptake. Numerous small molecules and larger compounds like proteins and antibodies have been successfully labeled with (124)I. Advances in radionuclide production allow the effective availability of sufficient quantities of (124)I on small biomedical cyclotrons for molecular imaging purposes. Radioiodination chemistry with (124)I relies on well-established radioiodine labeling methods, which consists mainly in nucleophilic and electrophilic substitution reactions. The physical characteristics of (124)I permit taking advantages of the higher PET image quality. The availability of new molecules that may be targeted with (124)I represents one of the more interesting reasons for the attention in nuclear medicine. We aim to discuss all iodine radioisotopes application focusing on (124)I, which seems to be the most promising for its half-life, radiation emissions, and stability, allowing several applications in oncological and nononcological fields.

Mild mental retardation in a child with a de novo interstitial deletion of 15q21.2q22.1: a comparison with previously described cases.

We report on a child with mild mental retardation, hypotelorism, blepharophimosis, face slight asymmetry and partial hypoplasia of corpus callosum, with an interstitial deletion of a chromosome 15. The deletion was molecularly characterized by array-CGH and FISH techniques. This rearrangement has a 7.18Mb extension and maps to 15q21.2q22.1. To date, there have been only six individuals reported with a deletion of 15q21; in three cases, the rearrangement was characterized by molecular cytogenetic techniques. After a comparison with these three cases, it appeared that the deletion we found is one of the smallest and it overlaps the distal portion of the ones taken into account. Finally, we tried to delineate the genotype-phenotype correlation in patients with a deletion of 15q21.