This paper presents an effective and efficient preprocessing algorithm for two-dimensional (2-D) electrocardiogram (ECG) compression to better compress irregular ECG signals by exploiting their inter- and intra-beat correlations. To better reveal the correlation structure, we first convert the ECG signal into a proper 2-D representation, or image. This involves a few steps including QRS detection and alignment, period sorting, and length equalization. The resulting 2-D ECG representation is then ready to be compressed by an appropriate image compression algorithm. We choose the state-of-the-art JPEG2000 for its high efficiency and flexibility. In this way, the proposed algorithm is shown to outperform some existing arts in the literature by simultaneously achieving high compression ratio (CR), low percent root mean squared difference (PRD), low maximum error (MaxErr), and low standard derivation of errors (StdErr). In particular, because the proposed period sorting method rearranges the detected heartbeats into a smoother image that is easier to compress, this algorithm is insensitive to irregular ECG periods. Thus either the irregular ECG signals or the QRS false-detection cases can be better compressed. This is a significant improvement over existing 2-D ECG compression methods. Moreover, this algorithm is not tied exclusively to JPEG2000. It can also be combined with other 2-D preprocessing methods or appropriate codecs to enhance the compression performance in irregular ECG cases.

You believe that organometallic compounds are sensitive towards air and moisture and can only be handled under an inert atmosphere? Wrong! Recent work by several groups shows how organometallic compounds, such as the Tc compound 1, are successfully used for the detection of biomolecules in an aerobic, aqueous environment. Using 1, the radiolabeling of single‐chain antibody fragments and serotonergic receptors in the central nervous system has been possible for the first time.

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(99m)Tc-sestamibi myocardial perfusion SPECT is a useful non-invasive imaging modality to detect cardiovascular involvement in SLE patients with non-specific clinical complaints of heart disease.

Gland size has been reported to have a major influence on localisation of parathyroid adenomas by technetium-99m methoxyisobutylisonitrile ((99m)Tc-MIBI) imaging. It has also been suggested that P-glycoprotein (Pgp) expression in parathyroid adenomas may influence localisation because false negative studies have been reported with large tumours and true positives with very small tumours. Therefore, the purpose of this study was to retrospectively evaluate the relationship between (99m)Tc-MIBI parathyroid imaging results and Pgp or multidrug resistance-related protein (MRP) expression in parathyroid adenomas. Before surgery, 47 patients with large parathyroid adenomas (larger than 1.5 g) underwent early and delayed parathyroid imaging, 10 min and 2 h after intravenous injection of (99m)Tc-MIBI. Immunohistochemical analyses (IHA) were performed, using multiple non-consecutive sections of the operative specimens, to detect Pgp or MRP expression. According to the results of IHA, the 34 parathyroid adenomas were separated into four groups: (1) three adenomas positive for both Pgp and MRP expression, (2) one adenoma positive for Pgp but negative for MRP expression, (3) four adenomas negative for Pgp but positive for MRP expression and (4) 39 adenomas with negative for both Pgp and MRP expression. All 39 adenomas in group 4 could be detected by (99m)Tc-MIBI parathyroid imaging. None of the eight adenomas in groups 1-3 could be detected by (99m)Tc-MIBI parathyroid imaging ( P<0.05). It is concluded that not only the size of parathyroid adenomas but also significant Pgp or MRP expression limits the sensitivity of (99m)Tc-MIBI imaging in localising parathyroid adenomas preoperatively.

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F-18 NaF using PET-CT system has significantly better sensitivity and specificity than conventional Tc-99m MDP BS in detecting metastatic HCC bone lesions that are predominantly osteolytic. The diagnostic result of PET-CT also serves as a more effective prognostic indictor for HCC patients.

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