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An optical link system (OLS) is to be used in the data acquisition (DAQ) system for the Silicon Vertex Detector of the KEK B-factory experiment (BELLE collaboration). In this study we report the 10-bit, or channel (ch), OLS in which CMOS ICs are used as the transceiver circuitry for both transmitting and receiving, infrared LEDs are used as photo transmitting devices, and Si PIN photodiodes (PDs) are used as photo-receiving devices. We have obtained a 32 Mbps/ch data rate, at around 5 dB of dynamic range, with less than 8 nsec of jitters and an error rate of less than [10.sup.-9]. The scheme we proposed in this study has been confirmed assuming it will be used in the readout system.

Objectives: The purpose of this study was to investigate the usefulness of a new scanning agent of technetium-99m-hexakis-2-methoxy-isobutyl-isonitrile (Tc-99m-MIBI) for the diagnosis of malignant tumours of the head and neck. Methods: Scintigraphy with Tc-99m-MIBI was performed in 19 patients with malignant turnouts of the head and neck. Factors of the early and delayed static scans (hot, warm or cold uptake), the early and delayed retention indexes, the blood flow index and the tumour retention index were obtained from Tc-99m-MIBI scintigraphy. Tumour retention indexes were classified into three grades; slightly (>0.9), moderately (0.9–0.8) and severely (0.8 >) decreased. Grade of tissue differentiation of tumour (well, moderately or poorly differentiated) and tumour size (T1 ∼ T4) were examined using the excised turnout. Scintigraphic indexes and tumour characteristics were compared. Results: The early static scan and tumour size showed a correlation with the blood flow index. However, the delayed static scan did not show any relationship with blood flow index and tumour size. The tumour retention index had a tendency to decrease in malignant turnouts, and showed a significant correlation with the grade of tissue differentiation of the tumour. Conclusions: The tendency of the tumour retention index to decrease in Tc-99m-MIBI scintigraphy showed the malignancy of tumour and would be useful for the diagnosis of malignant tumours of the head and neck. [ABSTRACT FROM AUTHOR]

Objectives: The purpose of this study was to compare the usefulness of technetium-99m hexakis-2-methoxyisobutylisonitrile (99Tcm-MIBI) and thallium-201-chloride (Tl-201) as scintigraphic agents. Methods: Dynamic and static scintigraphic imaging with 99Tcm-MIBI and Tl-201 were performed on patients with a variety of malignant and benign turnouts. Factors of the grade of the static scan, the blood flow index, the early and delayed retention indexes, and the tumour retention index were obtained from the scintigraphy. In addition to these factors, the grade of tissue differentiation and tumour size were evaluated to clarify the difference between 99Tcm-MIBI and Tl-201 for the diagnosis of malignant tumours of the head and neck. Results: 99Tcm-MIBI accumulation depended upon the blood flow index in the early static scan. but this accumulation did not correlate with tumour size. The accumulation in most subjects decreased in the delayed static scan, and the turnout retention index had a tendency to decrease with the grade of tissue differentiation. Tl 201 accumulation depended upon the blood flow index in the early static scan similar to 99Tcm-MIBI, and the accumulation correlated with turnout size, unlike 99Tcm-MIBI. The turnout retention index had a tendency to increase with the grade of tissue differentiation. Thus, the tumour retention indexes showed opposite behaviours between 99Tcm-MIBI and Tl 201, but they both accurately determined tumour malignancy. Conclusions: There was no major difference between 99Tcm-MIBI and Tl-201 scintigraphy with respect to accuracy of diagnosis of malignant tumours of the head and neck. However, 99Tcm-MIBI was superior to Tl-201 for small-size tumours and Tl-201 was useful for large-size turnouts. [ABSTRACT FROM AUTHOR]